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Xu Z, Lu Q, Jia D, Li S, Luo K, Su T, Chen Z, Qiu G. Significant biomagnification of methylmercury in songbird nestlings through a rice-based food web: Insights from stable mercury isotopes. JOURNAL OF HAZARDOUS MATERIALS 2024; 468:133783. [PMID: 38367440 DOI: 10.1016/j.jhazmat.2024.133783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 02/07/2024] [Accepted: 02/12/2024] [Indexed: 02/19/2024]
Abstract
To elucidate the sources and transfer of mercury (Hg) in terrestrial food chains, particularly in heavily Hg-contaminated rice paddy ecosystems, we collected rice leaves, invertebrates, and Russet Sparrow nestlings from a clear food chain and analyzed the dietary compositions and potential Hg sources using stable Hg isotopes coupled with a Bayesian isotope mixing model (BIMM). Our findings indicated that MeHg exposure is dominant through the dietary route, with caterpillars, grasshoppers, and katydids being the main prey items, while the less provisioned spiders, dragonflies, and mantises contributed the most of the Hg to nestlings. We found minimal MIF but certain MDF in this terrestrial food chain and identified two distinct MeHg sources of dietary exposure and maternal transfer. We firstly found that the dietary route contributed substantially (almost tenfold) more MeHg to the nestlings than maternal transfer. These findings offer new insights into the integration of Hg from the dietary route and maternal transfers, enhancing our understanding of fluctuating Hg exposure risk during the nestling stage. Our study suggested that Hg isotopes combined with BIMM is an effective approach for tracing Hg sources in birds and for gaining in-depth insight into the trophic transfers and biomagnification of MeHg in food chains.
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Affiliation(s)
- Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Qinhui Lu
- The Key Laboratory of Environment Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Provincial Engineering Research Center of Ecological Food Innovation, School of Public Health, Guizhou Medical University, Guiyang 550025, China
| | - Dongya Jia
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550001, China
| | - Shenghao Li
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550001, China
| | - Kang Luo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Ailaoshan Station for Subtropical Forest Ecosystem Studies, Chinese Academy of Sciences, Jingdong 676200, China
| | - Tongping Su
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education, Nanning Normal University, Nanning 530001, China
| | - Zhuo Chen
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550001, China.
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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2
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Monteiro LC, Vieira LCG, Bernardi JVE, Recktenvald MCNDN, Nery AFDC, Fernandes IO, de Miranda VL, da Rocha DMS, de Almeida R, Bastos WR. Mercury distribution, bioaccumulation, and biomagnification in riparian ecosystems from a neotropical savanna floodplain, Araguaia River, central Brazil. ENVIRONMENTAL RESEARCH 2024; 252:118906. [PMID: 38609069 DOI: 10.1016/j.envres.2024.118906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/01/2024] [Accepted: 04/08/2024] [Indexed: 04/14/2024]
Abstract
Litterfall is the main source of dry deposition of mercury (Hg) into the soil in forest ecosystems. The accumulation of Hg in soil and litter suggests the possibility of transfer to terrestrial invertebrates through environmental exposure or ingestion of plant tissues. We quantified total mercury (THg) concentrations in two soil layers (organic: 0-0.2 m; mineral: 0.8-1 m), litter, fresh leaves, and terrestrial invertebrates of the Araguaia River floodplain, aiming to evaluate the THg distribution among terrestrial compartments, bioaccumulation in invertebrates, and the factors influencing THg concentrations in soil and invertebrates. The mean THg concentrations were significantly different between the compartments evaluated, being higher in organic soil compared to mineral soil, and higher in litter compared to mineral soil and fresh leaves. Soil organic matter content was positively related to THg concentration in this compartment. The order Araneae showed significantly higher Hg concentrations among the most abundant invertebrate taxa. The higher Hg concentrations in Araneae were positively influenced by the concentrations determined in litter and individuals of the order Hymenoptera, confirming the process of biomagnification in the terrestrial trophic chain. In contrast, the THg concentrations in Coleoptera, Orthoptera and Hymenoptera were not significantly related to the concentrations determined in the soil, litter and fresh leaves. Our results showed the importance of organic matter for the immobilization of THg in the soil and indicated the process of biomagnification in the terrestrial food web, providing insights for future studies on the environmental distribution of Hg in floodplains.
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Affiliation(s)
- Lucas Cabrera Monteiro
- Programa de Pós-Graduação em Ecologia, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brazil; Núcleo de Estudos e Pesquisas Ambientais e Limnológicas, Faculdade UnB Planaltina, Universidade de Brasília, Planaltina, DF, Brazil; Laboratório de Geoestatística e Geodésia, Faculdade UnB Planaltina, Universidade de Brasília, Planaltina, DF, Brazil.
| | - Ludgero Cardoso Galli Vieira
- Núcleo de Estudos e Pesquisas Ambientais e Limnológicas, Faculdade UnB Planaltina, Universidade de Brasília, Planaltina, DF, Brazil
| | - José Vicente Elias Bernardi
- Laboratório de Geoestatística e Geodésia, Faculdade UnB Planaltina, Universidade de Brasília, Planaltina, DF, Brazil
| | | | | | - Iara Oliveira Fernandes
- Programa de Pós-Graduação em Ciências Ambientais, Faculdade UnB Planaltina, Universidade de Brasília, Planaltina, DF, Brazil
| | - Vinicius Lima de Miranda
- Programa de Pós-Graduação em Zoologia, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brazil
| | | | - Ronaldo de Almeida
- Laboratório de Biogeoquímica Ambiental, Universidade Federal de Rondônia, Porto Velho, RO, Brazil
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Rebolloso-Hernández CA, Vallejo-Pérez MR, Carrizales-Yáñez L, Garrigos-Lomelí GJ, Razo-Soto I, Diaz-Barriga F. Arsenic and mercury exposure in different insect trophic guilds from mercury mining areas in Mexico. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:422. [PMID: 38570386 DOI: 10.1007/s10661-024-12571-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 03/23/2024] [Indexed: 04/05/2024]
Abstract
The exposure to arsenic and mercury in various insect trophic guilds from two mercury mining sites in Mexico was assessed. The two study sites were La Laja (LL) and La Soledad (LS) mines. Additionally, a reference site (LSR) was evaluated for LS. The terrestrial ecosystem was studied at LL, whereas both the terrestrial ecosystem and a stream called El Cedral (EC) were assessed at LS. The study sites are situated in the Biosphere Reserve Sierra Gorda (BRSG). Mercury vapor concentrations were measured with a portable analyzer, and concentrations of arsenic and mercury in environmental and biological samples were determined through atomic absorption spectrophotometry. Both pollutants were detected in all terrestrial ecosystem components (soil, air, leaves, flowers, and insects) from the two mines. The insect trophic guilds exposed included pollinivores, rhizophages, predators, coprophages, and necrophages. In LS, insects accumulated arsenic at levels 29 to 80 times higher than those found in specimens from LSR, and 10 to 46 times higher than those from LL. Similarly, mercury exposure in LS was 13 to 62 times higher than LSR, and 15 to 54 times higher than in LL. The analysis of insect exposure routes indicated potential exposure through air, soil, leaves, flowers, animal prey, carrion, and excrement. Water and sediment from EC exhibited high levels of arsenic and mercury compared to reference values, and predatory aquatic insects were exposed to both pollutants. In conclusion, insects from mercury mining sites in the BRSG are at risk.
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Affiliation(s)
- Carlos Alberto Rebolloso-Hernández
- Programa Multidisciplinario de Posgrado en Ciencias Ambientales, Universidad Autónoma de San Luis Potosí, 78000, San Luis Potosí, Mexico
| | - Moisés Roberto Vallejo-Pérez
- Programa Multidisciplinario de Posgrado en Ciencias Ambientales, Universidad Autónoma de San Luis Potosí, 78000, San Luis Potosí, Mexico.
- CONAHCYT-Universidad Autónoma de San Luis Potosí, 78000, San Luis Potosí, Mexico.
| | - Leticia Carrizales-Yáñez
- Facultad de Medicina-Centro de Investigación Aplicada en Ambiente y Salud (CIAAS), Universidad Autónoma de San Luis Potosí, 78210, San Luis Potosí, Mexico
| | - Giulio Jordan Garrigos-Lomelí
- Licenciatura en Ciencias Ambientales-Facultad de Medicina, Universidad Autónoma de San Luis Potosí, 78210, San Luis Potosí, Mexico
| | - Israel Razo-Soto
- Facultad de Ingeniería, Universidad Autónoma de San Luis Potosí, 78210, San Luis Potosí, Mexico
| | - Fernando Diaz-Barriga
- División de Estudios Superiores para la Paz, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, 78210, San Luis Potosí, Mexico
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Luo K, Yuan W, Lu Z, Xiong Z, Lin CJ, Wang X, Feng X. Unveiling the Sources and Transfer of Mercury in Forest Bird Food Chains Using Techniques of Vivo-Nest Video Recording and Stable Isotopes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6007-6018. [PMID: 38513264 DOI: 10.1021/acs.est.3c10972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Knowledge gaps in mercury (Hg) biomagnification in forest birds, especially in the most species-rich tropical and subtropical forests, limit our understanding of the ecological risks of Hg deposition to forest birds. This study aimed to quantify Hg bioaccumulation and transfer in the food chains of forest birds in a subtropical montane forest using a bird diet recorded by video and stable Hg isotope signals of biological and environmental samples. Results show that inorganic mercury (IHg) does not biomagnify along food chains, whereas methylmercury (MeHg) has trophic magnification factors of 7.4-8.1 for the basal resource-invertebrate-bird food chain. The video observations and MeHg mass balance model suggest that Niltava (Niltava sundara) nestlings ingest 78% of their MeHg from forest floor invertebrates, while Flycatcher (Eumyias thalassinus) nestlings ingest 59% from emergent aquatic invertebrates (which fly onto the canopy) and 40% from canopy invertebrates. The diet of Niltava nestlings contains 40% more MeHg than that of Flycatcher nestlings, resulting in a 60% higher MeHg concentration in their feather. Hg isotopic model shows that atmospheric Hg0 is the main Hg source in the forest bird food chains and contributes >68% in most organisms. However, three categories of canopy invertebrates receive ∼50% Hg from atmospheric Hg2+. Overall, we highlight the ecological risk of MeHg exposure for understory insectivorous birds caused by atmospheric Hg0 deposition and methylation on the forest floor.
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Affiliation(s)
- Kang Luo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Wei Yuan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Zhiyun Lu
- Ailaoshan Station for Subtropical Forest Ecosystem Studies, Chinese Academy of Sciences, Jingdong, Yunnan 676200, China
| | - Zichun Xiong
- Ailaoshan Station for Subtropical Forest Ecosystem Studies, Chinese Academy of Sciences, Jingdong, Yunnan 676200, China
| | - Che-Jen Lin
- Center for Advances in Water and Air Quality, Lamar University, Beaumont, Texas 77710, United States
| | - Xun Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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5
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Brown MK, Haskins DL, Pilgrim MA, Tuberville TD. Mercury bioaccumulation and Hepatozoon spp. infections in two syntopic watersnakes in South Carolina. ECOTOXICOLOGY (LONDON, ENGLAND) 2024; 33:164-176. [PMID: 38329640 DOI: 10.1007/s10646-024-02736-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/25/2024] [Indexed: 02/09/2024]
Abstract
Mercury (Hg) is a ubiquitous environmental contaminant known to bioaccumulate in biota and biomagnify in food webs. Parasites occur in nearly every ecosystem and often interact in complex ways with other stressors that their hosts experience. Hepatozoon spp. are intraerythrocytic parasites common in snakes. The Florida green watersnake (Nerodia floridana) and the banded watersnake (Nerodia fasciata) occur syntopically in certain aquatic habitats in the Southeastern United States. The purpose of this study was to investigate relationships among total mercury (THg) concentrations, body size, species, habitat type and prevalence and parasitemia of Hepatozoon spp. infections in snakes. In the present study, we sampled N. floridana and N. fasciata from former nuclear cooling reservoirs and isolated wetlands of the Savannah River Site in South Carolina. We used snake tail clips to quantify THg and collected blood samples for hemoparasite counts. Our results indicate a significant, positive relationship between THg and snake body size in N. floridana and N. fasciata in both habitats. Average THg was significantly higher for N. fasciata compared to N. floridana in bays (0.22 ± 0.02 and 0.08 ± 0.006 mg/kg, respectively; p < 0.01), but not in reservoirs (0.17 ± 0.02 and 0.17 ± 0.03 mg/kg, respectively; p = 0.29). Sex did not appear to be related to THg concentration or Hepatozoon spp. infections in either species. We found no association between Hg and Hepatozoon spp. prevalence or parasitemia; however, our results suggest that species and habitat type play a role in susceptibility to Hepatozoon spp. infection.
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Affiliation(s)
- M Kyle Brown
- University of Georgia's Savannah River Ecology Laboratory, Aiken, SC, 29802, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
| | - David Lee Haskins
- University of Georgia's Savannah River Ecology Laboratory, Aiken, SC, 29802, USA.
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA.
- Interdisciplinary Toxicology Program, University of Georgia, Athens, GA, 30602, USA.
- U.S. Geological Survey, Eastern Ecological Science Center at Patuxent Research Refuge, Laurel, MD, 20708, USA.
| | - Melissa A Pilgrim
- University of Georgia's Savannah River Ecology Laboratory, Aiken, SC, 29802, USA
- University of South Carolina Upstate, Spartanburg, SC, 29303, USA
| | - Tracey D Tuberville
- University of Georgia's Savannah River Ecology Laboratory, Aiken, SC, 29802, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
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6
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Fernandes IO, Monteiro LC, de Miranda VL, Rodrigues YOS, de Freitas Muniz DH, de Castro Paes É, Bernardi JVE. Mercury distribution in organisms, litter, and soils of the Middle Araguaia floodplain in Brazil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:20925-20940. [PMID: 38379047 DOI: 10.1007/s11356-024-32317-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 01/29/2024] [Indexed: 02/22/2024]
Abstract
Mercury (Hg) is a chemical element that, depending on its concentration, may become toxic to living organisms due to the ability of Hg to bioaccumulate in food chains. In this study, we collected samples of soil, litter, and organisms in the Middle Araguaia floodplain, Brazil. Total mercury (THg) concentrations in litter were significantly higher (p < 0.0001) than that in soil, ranging from 10.68 ± 0.55 to 48.94 ± 0.13 and 20.80 ± 1.07 to 55 .19 ± 1.59 ng g-1, respectively. Total mercury concentration levels in soil showed a linear, inversely proportional relationship with soil organic matter (SOM) contents and soil pH, consistent with the geochemical behavior of chemical elements in flooded environments. Ten orders of organisms were identified, and the average THg concentrations determined in their bodies were up to 20 times higher than those in soil and litter. We found a significant linear relationship between the levels of THg in litter and those found in soil organisms, thereby allowing the prediction of THg concentration levels in soil organisms through the analysis of litter at the sample units. The different dynamics and feeding habits of soil organisms and the concentration of THg in these organisms may be influenced by the river's course. This study provides evidence of the bioaccumulation of THg in soil organisms in the floodplain of the Middle Araguaia River, an important river basin in the Brazilian savanna.
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Affiliation(s)
- Iara Oliveira Fernandes
- Graduate Program in Environmental Sciences, Faculty UnB Planaltina, University of Brasília, Planaltina, Distrito Federal, 73345-010, Brazil.
| | - Lucas Cabrera Monteiro
- Graduate Program in Ecology, Institute of Biological Sciences, University of Brasília, Brasília, Distrito Federal, 70910-900, Brazil
| | - Vinícius Lima de Miranda
- Graduate Program in Zoology, Institute of Biological Sciences, University of Brasília, Brasília, Distrito Federal, 70910-900, Brazil
| | - Ygor Oliveira Sarmento Rodrigues
- Graduate Program in Environmental Sciences, Faculty UnB Planaltina, University of Brasília, Planaltina, Distrito Federal, 73345-010, Brazil
| | - Daphne Heloisa de Freitas Muniz
- Graduate Program in Environmental Sciences, Faculty UnB Planaltina, University of Brasília, Planaltina, Distrito Federal, 73345-010, Brazil
| | - Ésio de Castro Paes
- Graduate Program in Soils and Plant Nutrition, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil
| | - José Vicente Elias Bernardi
- Graduate Program in Environmental Sciences, Faculty UnB Planaltina, University of Brasília, Planaltina, Distrito Federal, 73345-010, Brazil
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7
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Tornabene BJ, Hossack BR, Halstead BJ, Eagles-Smith CA, Adams MJ, Backlin AR, Brand AB, Emery CS, Fisher RN, Fleming J, Glorioso BM, Grear DA, Grant EHC, Kleeman PM, Miller DAW, Muths E, Pearl CA, Rowe JC, Rumrill CT, Waddle JH, Winzeler ME, Smalling KL. Broad-Scale Assessment of Methylmercury in Adult Amphibians. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17511-17521. [PMID: 37902062 PMCID: PMC10653216 DOI: 10.1021/acs.est.3c05549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 10/31/2023]
Abstract
Mercury (Hg) is a toxic contaminant that has been mobilized and distributed worldwide and is a threat to many wildlife species. Amphibians are facing unprecedented global declines due to many threats including contaminants. While the biphasic life history of many amphibians creates a potential nexus for methylmercury (MeHg) exposure in aquatic habitats and subsequent health effects, the broad-scale distribution of MeHg exposure in amphibians remains unknown. We used nonlethal sampling to assess MeHg bioaccumulation in 3,241 juvenile and adult amphibians during 2017-2021. We sampled 26 populations (14 species) across 11 states in the United States, including several imperiled species that could not have been sampled by traditional lethal methods. We examined whether life history traits of species and whether the concentration of total mercury in sediment or dragonflies could be used as indicators of MeHg bioaccumulation in amphibians. Methylmercury contamination was widespread, with a 33-fold difference in concentrations across sites. Variation among years and clustered subsites was less than variation across sites. Life history characteristics such as size, sex, and whether the amphibian was a frog, toad, newt, or other salamander were the factors most strongly associated with bioaccumulation. Total Hg in dragonflies was a reliable indicator of bioaccumulation of MeHg in amphibians (R2 ≥ 0.67), whereas total Hg in sediment was not (R2 ≤ 0.04). Our study, the largest broad-scale assessment of MeHg bioaccumulation in amphibians, highlights methodological advances that allow for nonlethal sampling of rare species and reveals immense variation among species, life histories, and sites. Our findings can help identify sensitive populations and provide environmentally relevant concentrations for future studies to better quantify the potential threats of MeHg to amphibians.
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Affiliation(s)
- Brian J. Tornabene
- U.S.
Geological Survey, Northern Rocky Mountain
Science Center, Missoula, Montana 59801, United States
| | - Blake R. Hossack
- U.S.
Geological Survey, Northern Rocky Mountain
Science Center, Missoula, Montana 59801, United States
- Wildlife
Biology Program, W. A. Franke College of Forestry & Conservation, University of Montana, Missoula, Montana 59812, United States
| | - Brian J. Halstead
- U.S.
Geological Survey, Western Ecological Research
Center, Dixon, California 95620, United States
| | - Collin A. Eagles-Smith
- U.S.
Geological Survey, Forest and Rangeland
Ecosystem Science Center, Corvallis, Oregon 97331 United States
| | - Michael J. Adams
- U.S.
Geological Survey, Forest and Rangeland
Ecosystem Science Center, Corvallis, Oregon 97331 United States
| | - Adam R. Backlin
- U.S.
Geological Survey, Western Ecological Research
Center, San Diego, California 92101, United States
| | - Adrianne B. Brand
- U.S. Geological
Survey, Eastern Ecological Science Center
(Patuxent Wildlife Research Center), Turners Falls, Massachusetts 01376, United States
| | - Colleen S. Emery
- U.S.
Geological Survey, Forest and Rangeland
Ecosystem Science Center, Corvallis, Oregon 97331 United States
| | - Robert N. Fisher
- U.S.
Geological Survey, Western Ecological Research
Center, San Diego, California 92101, United States
| | - Jill Fleming
- U.S. Geological
Survey, Eastern Ecological Science Center
(Patuxent Wildlife Research Center), Turners Falls, Massachusetts 01376, United States
| | - Brad M. Glorioso
- U.S.
Geological
Survey, Wetland and Aquatic Research Center, Lafayette, Louisiana 70506, United States
| | - Daniel A. Grear
- U.S.
Geological
Survey, National Wildlife Health Center, Madison, Wisconsin 53711, United States
| | - Evan H. Campbell Grant
- U.S. Geological
Survey, Eastern Ecological Science Center
(Patuxent Wildlife Research Center), Turners Falls, Massachusetts 01376, United States
| | - Patrick M. Kleeman
- U.S.
Geological
Survey, Western Ecological Research Center, Point Reyes Station, California 94956, United States
| | - David A. W. Miller
- Department
of Ecosystem Science and Management, Pennsylvania
State University, University Park, Pennsylvania 16802, United States
| | - Erin Muths
- U.S. Geological
Survey, Fort Collins Science Center, Fort Collins, Colorado 80526, United States
| | - Christopher A. Pearl
- U.S.
Geological Survey, Forest and Rangeland
Ecosystem Science Center, Corvallis, Oregon 97331 United States
| | - Jennifer C. Rowe
- U.S.
Geological Survey, Forest and Rangeland
Ecosystem Science Center, Corvallis, Oregon 97331 United States
| | - Caitlin T. Rumrill
- U.S.
Geological Survey, Forest and Rangeland
Ecosystem Science Center, Corvallis, Oregon 97331 United States
| | - J. Hardin Waddle
- U.S. Geological
Survey, Wetland and Aquatic Research Center, Gainesville, Florida 32653, United States
| | - Megan E. Winzeler
- U.S.
Geological
Survey, National Wildlife Health Center, Madison, Wisconsin 53711, United States
| | - Kelly L. Smalling
- U.S. Geological
Survey, New Jersey Water Science Center, Lawrenceville, New Jersey 08648, United States
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8
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Xu Z, Lu Q, Xu X, Liang L, Abeysinghe KS, Chen Z, Qiu G. Aquatic methylmercury is a significant subsidy for terrestrial songbirds: Evidence from the odd mass-independent fractionation of mercury isotopes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 880:163217. [PMID: 37011675 DOI: 10.1016/j.scitotenv.2023.163217] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 05/27/2023]
Abstract
In contrast to aquatic food chains, knowledge of the origins and transfer of mercury (Hg) and methylmercury (MeHg) in terrestrial food chains is relatively limited, especially in songbirds. We collected soil, rice plants, aquatic and terrestrial invertebrates, small wild fish, and resident songbird feathers from an Hg-contaminated rice paddy ecosystem for an analysis of stable Hg isotopes to clarify the sources of Hg and its transfer in songbirds and their prey. Significant mass-dependent fractionation (MDF, δ202Hg), but no mass-independent fractionation (MIF, ∆199Hg) occurred in the trophic transfers in terrestrial food chains. Piscivorous, granivorous, and frugivorous songbirds and aquatic invertebrates were all characterized by elevated Δ199Hg values. The estimated MeHg isotopic compositions obtained using linear fitting and a binary mixing model explained both the terrestrial and aquatic origins of MeHg in the terrestrial food chains. We found that MeHg from aquatic habitats is an important subsidy for terrestrial songbirds, even those that feed mainly on seeds, fruits, or cereals. The results show that MIF of the MeHg isotope is a reliable tool to reveal MeHg sources in songbirds. Because the MeHg isotopic compositions was calculated with a binary mixing model or directly estimated from the high proportions of MeHg, compound-specific isotope analysis of Hg would be more useful for the interpretation of the Hg sources, and is highly recommended for future studies.
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Affiliation(s)
- Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Qinhui Lu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; The Key Laboratory of Environment Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
| | - Xiaohang Xu
- College of Resources and Environmental Engineering, Guizhou University, Guiyang 550025, China; Key Laboratory of Karst Georesources and Environment (Guizhou University), Ministry of Education, Guiyang 550025, China
| | - Longchao Liang
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550001, China
| | - Kasun S Abeysinghe
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Zhuo Chen
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550001, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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9
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Parker KH, Bishop JM, Serieys LEK, Mateo R, Camarero PR, Leighton GRM. A heavy burden: Metal exposure across the land-ocean continuum in an adaptable carnivore. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 327:121585. [PMID: 37040831 DOI: 10.1016/j.envpol.2023.121585] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/10/2023] [Accepted: 04/04/2023] [Indexed: 06/19/2023]
Abstract
Urbanisation and associated anthropogenic activities release large quantities of toxic metals and metalloids into the environment, where they may bioaccumulate and threaten both wildlife and human health. In highly transformed landscapes, terrestrial carnivores may be at increased risk of exposure through biomagnification. We quantified metallic element and metalloid exposure in blood of caracals (Caracal caracal), an adaptable felid inhabiting the rapidly urbanising, coastal metropole of Cape Town, South Africa. Using redundancy analysis and mixed-effect models, we explored the influence of demography, landscape use, and diet on the concentration of 11 metals and metalloids. Although species-specific toxic thresholds are lacking, arsenic (As) and chromium (Cr) were present at potentially sublethal levels in several individuals. Increased use of human-transformed landscapes, particularly urban areas, roads, and vineyards, was significantly associated with increased exposure to aluminium (Al), cobalt (Co) and lead (Pb). Foraging closer to the coast and within aquatic food webs was associated with increased levels of mercury (Hg), selenium (Se) and arsenic, where regular predation on seabirds and waterbirds likely facilitates transfer of metals from aquatic to terrestrial food webs. Further, several elements were linked to lower haemoglobin levels (chromium, mercury, manganese, and zinc) and elevated levels of infection-fighting cells (mercury and selenium). Our results highlight the importance of anthropogenic activities as major environmental sources of metal contamination in terrestrial wildlife, including exposure across the land-ocean continuum. These findings contribute towards the growing evidence suggesting cities are particularly toxic areas for wildlife. Co-exposure to a suite of metal pollutants may threaten the long-term health and persistence of Cape Town's caracal population in unexpected ways, particularly when interacting with additional known pollutant and pathogen exposure. The caracal is a valuable sentinel for assessing metal exposure and can be used in pollution monitoring programmes to mitigate exposure and promote biodiversity conservation in human-dominated landscapes.
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Affiliation(s)
- Kim H Parker
- Institute for Communities and Wildlife in Africa (iCWild), Department of Biological Sciences, University of Cape Town, South Africa
| | - Jacqueline M Bishop
- Institute for Communities and Wildlife in Africa (iCWild), Department of Biological Sciences, University of Cape Town, South Africa
| | - Laurel E K Serieys
- Institute for Communities and Wildlife in Africa (iCWild), Department of Biological Sciences, University of Cape Town, South Africa; Panthera, New York, NY, USA; Cape Leopard Trust, Cape Town, South Africa
| | - Rafael Mateo
- Instituto de Investigación en Recursos Cinegéticos (IREC-CSIC, UCLM, JCCM), Ciudad Real, Spain
| | - Pablo R Camarero
- Instituto de Investigación en Recursos Cinegéticos (IREC-CSIC, UCLM, JCCM), Ciudad Real, Spain
| | - Gabriella R M Leighton
- Institute for Communities and Wildlife in Africa (iCWild), Department of Biological Sciences, University of Cape Town, South Africa; Department of Zoology and Entomology, Rhodes University, Grahamstown, South Africa.
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10
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Zhang J, Li C, Tang W, Wu M, Chen M, He H, Lei P, Zhong H. Mercury in wetlands over 60 years: Research progress and emerging trends. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161862. [PMID: 36716881 DOI: 10.1016/j.scitotenv.2023.161862] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/04/2023] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
Wetlands are considered the hotspots for mercury (Hg) biogeochemistry, garnering global attention. Therefore, it is important to review the research progress in this field and predict future frontiers. To achieve that, we conducted a literature analysis by collecting 15,813 publications about Hg in wetlands from the Web of Science Core Collection. The focus of wetland Hg research has changed dramatically over time: 1) In the initial stage (i.e., 1959-1990), research mainly focused on investigating the sources and contents of Hg in wetland environments and fish. 2) For the next 20 years (i.e., 1991-2010), Hg transformation (e.g., Hg reduction and methylation) and environmental factors that affect Hg bioaccumulation have attracted extensive attention. 3) In the recent years of 2011-2022, hot topics in Hg study include microbial Hg methylators, Hg bioavailability, methylmercury (MeHg) demethylation, Hg stable isotope, and Hg cycling in paddy fields. Finally, we put forward future research priorities, i.e., 1) clarifying the primary factors controlling MeHg production, 2) uncovering the MeHg demethylation process, 3) elucidating MeHg bioaccumulation process to better predict its risk, and 4) recognizing the role of wetlands in Hg circulation. This research shows a comprehensive knowledge map for wetland Hg research and suggests avenues for future studies.
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Affiliation(s)
- Jin Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Chengjun Li
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Wenli Tang
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Mengjie Wu
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Mingying Chen
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Huan He
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Pei Lei
- School of Environment, Nanjing Normal University, Nanjing 210023, China.
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing 210023, China; Environmental and Life Science Program (EnLS), Trent University, Peterborough, Ontario, Canada
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11
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Rebolloso Hernández CA, Vallejo Pérez MR, Razo Soto I, Díaz-Barriga Martínez F, Yáñez LC. Mercury entomotoxicology. CHEMOSPHERE 2023; 311:136965. [PMID: 36280115 DOI: 10.1016/j.chemosphere.2022.136965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/03/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
Mercury is an industrial pollutant of global concern. Currently entomofauna is disappearing and chemical pollution is one cause, however, it is unknown whether mercury is an additional threat. Therefore, it is necessary to know the entomotoxicology of mercury. The aim of the present work was to perform a comprehensive literature review on the entomotoxicology of mercury. The toxicokinetics and toxicity of mercury in insects, the participation of insects in the mercury cycle and the fact that this element is a threat to entomofauna are characterized. Insects can be exposed to mercury through ingestion, tracheal respiration, and gill respiration. Organic forms of mercury are better absorbed, bioaccumulated and distributed than inorganic forms. In addition, insects can biotransform mercury, for example, by methylating it. Metal elimination occurs through feces, eggs and exuvia. Toxicity molecular mechanisms include oxidative stress, enzymatic disruptions, alterations in the metabolism of neurotransmitters and proteins, genotoxicity, cell death and unbalances in the energetic state. Moreover, mercury affects lipid, germ, and gut cells, causes deformations, disturbs development, reproduction, behavior, and locomotion, besides to alters insect populations and communities. In terrestrial ecosystems, entomofauna participate in the mercury cycle by bioaccumulating mercury from soil and air, predating, being predated and decomposing organic matter. In aquatic ecosystems insects participate by accumulating mercury from water and sediment, predating, being predated and transporting it to terrestrial ecosystems when they emerge as winged adults. There are still information gaps that need to be addressed.
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Affiliation(s)
- Carlos Alberto Rebolloso Hernández
- Programa Multidisciplinario de Posgrado en Ciencias Ambientales, Universidad Autónoma de San Luis Potosí, Avenida Manuel Nava No. 201, CP 78210, Zona Universitaria, San Luis Potosí, SLP, Mexico.
| | - Moisés Roberto Vallejo Pérez
- CONACYT, Coordinación para la Innovación y Aplicación de la Ciencia y Tecnología (CIACYT), Universidad Autónoma de San Luis Potosí, Avenida Sierra Leona No. 550, CP 78210, Colonia Lomas Segunda Sección, San Luis Potosí, SLP, Mexico
| | - Israel Razo Soto
- Facultad de Ingeniería, Universidad Autónoma de San Luis Potosí, Avenida Manuel Nava No. 304, CP 78210, Zona Universitaria, San Luis Potosí, SLP, Mexico
| | - Fernando Díaz-Barriga Martínez
- Facultad de Medicina-Centro de Investigación Aplicada en Ambiente y Salud (CIAAS), Universidad Autónoma de San Luis Potosí, Avenida Sierra Leona No. 550, CP 78210, Colonia Lomas Segunda Sección, San Luis Potosí, SLP, Mexico
| | - Leticia Carrizales Yáñez
- Facultad de Medicina-Centro de Investigación Aplicada en Ambiente y Salud (CIAAS), Universidad Autónoma de San Luis Potosí, Avenida Sierra Leona No. 550, CP 78210, Colonia Lomas Segunda Sección, San Luis Potosí, SLP, Mexico
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12
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Li C, Luo K, Shao Y, Xu X, Chen Z, Liang T, Xu Z, Dong X, Wang H, Qiu G. Total and methylmercury concentrations in nocturnal migratory birds passing through Mount Ailao, Southwest China. ENVIRONMENTAL RESEARCH 2022; 215:114373. [PMID: 36165871 DOI: 10.1016/j.envres.2022.114373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
Despite growing concerns over mercury (Hg) accumulation in birds in recent decades, little is known about Hg exposure in nocturnal migratory birds. Here, total mercury (THg) and methylmercury (MeHg) were detected in the feathers of nocturnal migratory birds (n = 286, belonging to 46 species) passing through Mount Ailao in Southwest China. The stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were also determined to clarify the effects of trophic position, foraging guild, and foraging behavior on Hg bioaccumulation. Our results show that the THg and MeHg concentrations varied by two orders of magnitude among all nocturnal migratory birds investigated, with the lowest values (THg: 0.056 mg kg-1; MeHg: 0.038 mg kg-1) in the Asian koel (Eudynamys scolopaceus) and the highest (THg: 12 mg kg-1; MeHg: 7.8 mg kg-1) in the hair-crested drongo (Dicrurus hottentottus). Waterbirds showed higher δ15N values and higher THg and MeHg concentrations than songbirds, and the Hg concentrations in piscivorous species were significantly higher than those in herbivores, omnivores, and insectivores. Significant effects of foraging guilds (Kruskal-Wallis one-way ANOVA, p < 0.001) and foraging behaviors (Kruskal-Wallis one-way ANOVA, p < 0.001) on the Hg concentrations in migratory bird feathers were detected. A risk assessment indicated that approximately 7.0% of individuals were at moderate (2.4-5.0 mg kg-1) to high (>5.0 mg kg-1) risk of Hg exposure, and were therefore vulnerable to adverse physiological and behavioral effects. A long-term monitoring campaign during the migratory period is highly recommended to better understand the bioaccumulation of Hg in these nocturnal migratory bird populations over time.
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Affiliation(s)
- Chan Li
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Kang Luo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuxiao Shao
- School of Geography and Environmental Science, Guizhou Normal University, Guiyang, 550001, China
| | - Xiaohang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhuo Chen
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China.
| | - Tao Liang
- Zhenyuan Management and Protection Bureau of Ailao Mountain National Nature Reserve, Zhenyuan, 666500, China
| | - Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xian Dong
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Hongdong Wang
- Zhenyuan Management and Protection Bureau of Ailao Mountain National Nature Reserve, Zhenyuan, 666500, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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13
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Rundio DE, Rivera R, Weiss-Penzias PS. High mercury concentrations in steelhead/rainbow trout, sculpin, and terrestrial invertebrates in a stream-riparian food web in coastal California. ECOTOXICOLOGY (LONDON, ENGLAND) 2022; 31:1506-1519. [PMID: 36449122 PMCID: PMC9709357 DOI: 10.1007/s10646-022-02608-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 11/20/2022] [Indexed: 06/17/2023]
Abstract
Stream and riparian food webs are connected by cross-habitat exchanges of invertebrate prey that can transfer contaminants including mercury. Marine fog has been identified as a source of methylmercury (MeHg) to some terrestrial food webs in coastal California, suggesting that terrestrial invertebrates might have elevated MeHg relative to stream invertebrates and might lead to higher mercury exposure in fish that consume terrestrial subsidies. As an initial step to examine this possibility, we analyzed mercury concentrations in terrestrial and aquatic invertebrates and two fish species, steelhead/rainbow trout (Oncorhynchus mykiss) and coastrange sculpin (Cottus aleuticus), in a small watershed. Mean MeHg and total mercury (THg) concentrations in terrestrial invertebrates were three to four times higher than in aquatic invertebrates of the same trophic level. MeHg was >1000 ng/g dw in some individual centipede and scorpion samples, and also relatively high (100-300 ng/g dw) in some terrestrial detritivores, including non-native isopods. Mean THg in age 0 trout was 400 ng/g dw compared to 1200-1300 ng/g dw in age 1+ trout and sculpin, and the largest trout sampled had THg >3500 ng/g dw. However, the similar mercury concentrations between age 1+ trout and sculpin, despite different diet types, indicated that Hg concentrations in fish were not related simply to differences in consumption of terrestrial invertebrates. The high mercury concentrations we found in terrestrial invertebrates and fish suggest that further research on the sources and bioaccumulation of mercury is warranted in this region where O. mykiss populations are threatened.
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Affiliation(s)
- David E Rundio
- Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 110 McAllister Way, Santa Cruz, CA, 95060, USA.
| | - Roberto Rivera
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
- Department of Materials Science and Engineering, University of California, Irvine, 544 Engineering Tower, Irvine, CA, 92697, USA
| | - Peter S Weiss-Penzias
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
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14
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Lemaire J, Brischoux F, Marquis O, Mangione R, Caut S, Brault-Favrou M, Churlaud C, Bustamante P. Relationships between stable isotopes and trace element concentrations in the crocodilian community of French Guiana. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 837:155846. [PMID: 35561901 DOI: 10.1016/j.scitotenv.2022.155846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 04/26/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Trace elements in the blood of crocodilians and the factors that influence their concentrations are overall poorly documented. However, determination of influencing factors is crucial to assess the relevance of caimans as bioindicators of environmental contamination, and potential toxicological impact of trace elements on these reptiles. In the present study, we determined the concentrations of 14 trace elements (Ag, As, Cd, Cr, Co, Cu, Fe, Hg, Pb, Mn, Ni, Se, V, and Zn) in the blood of four French Guiana caiman species (the Spectacled Caiman Caiman crocodilus [n = 34], the Black Caiman Melanosuchus niger [n = 25], the Dwarf Caiman Paleosuchus palpebrosus [n = 5] and the Smooth-fronted Caiman Paleosuchus trigonatus [n = 20]) from 8 different sites, and further investigated the influence of individual body size and stable isotopes as proxies of foraging habitat and trophic position on trace element concentrations. Trophic position was identified to be an important factor influencing trace element concentrations in the four caiman species and explained interspecific variations. These findings highlight the need to consider trophic ecology when crocodilians are used as bioindicators of trace element contamination in environmental studies.
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Affiliation(s)
- Jérémy Lemaire
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-La Rochelle Université, 79360 Villiers en Bois, France; Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France.
| | - François Brischoux
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-La Rochelle Université, 79360 Villiers en Bois, France
| | - Oliver Marquis
- Muséum national d'Histoire naturelle, Parc Zoologique de Paris, 53 avenue de Saint Maurice, 75012 Paris, France
| | - Rosanna Mangione
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
| | - Stéphane Caut
- Consejo Superior de Investigaciones Cientificas (CSIC), Departamento de Etologia y Conservation de La Biodiversidad - Estacion Biologica de Doñana - C/Americo Vespucio, S/n (Isla de La Cartuja), E-41092 Sevilla, Spain; ANIMAVEG Conservation, 58 Avenue Du Président Salvador Allende, F-94800 Villejuif, France
| | - Maud Brault-Favrou
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France
| | - Carine Churlaud
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France
| | - Paco Bustamante
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France; Institut Universitaire de France (IUF), 1 rue Descartes, 75005 Paris, France
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15
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Short-term mercury exposure disrupts muscular and hepatic lipid metabolism in a migrant songbird. Sci Rep 2022; 12:11470. [PMID: 35794224 PMCID: PMC9259677 DOI: 10.1038/s41598-022-15680-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/28/2022] [Indexed: 11/18/2022] Open
Abstract
Methylmercury (MeHg) is a global pollutant that can cause metabolic disruptions in animals and thereby potentially compromise the energetic capacity of birds for long-distance migration, but its effects on avian lipid metabolism pathways that support endurance flight and stopover refueling have never been studied. We tested the effects of short-term (14-d), environmentally relevant (0.5 ppm) dietary MeHg exposure on lipid metabolism markers in the pectoralis and livers of yellow-rumped warblers (Setophaga coronata) that were found in a previous study to have poorer flight endurance in a wind tunnel than untreated conspecifics. Compared to controls, MeHg-exposed birds displayed lower muscle aerobic and fatty acid oxidation capacity, but similar muscle glycolytic capacity, fatty acid transporter expression, and PPAR expression. Livers of exposed birds indicated elevated energy costs, lower fatty acid uptake capacity, and lower PPAR-γ expression. The lower muscle oxidative enzyme capacity of exposed birds likely contributed to their weaker endurance in the prior study, while the metabolic changes observed in the liver have potential to inhibit lipogenesis and stopover refueling. Our findings provide concerning evidence that fatty acid catabolism, synthesis, and storage pathways in birds can be dysregulated by only brief exposure to MeHg, with potentially significant consequences for migratory performance.
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16
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Bajracharya SS, Zahor DL, Glynn KJ, Gratz LE, Cornelius JM. Feather mercury concentrations in omnivorous and granivorous terrestrial songbirds in Southeast Michigan. ECOTOXICOLOGY (LONDON, ENGLAND) 2022; 31:797-807. [PMID: 35445955 DOI: 10.1007/s10646-022-02545-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
Sublethal exposure to methylmercury (MeHg) can have consequences for the reproductive, neurological, and physiological health of birds. Songbirds, regardless of trophic position, are often exposed to mercury (Hg) and may be at risk for health effects - especially if they inhabit a place that is subject to high Hg atmospheric deposition and/or have local conditions that are prone to methylation. This study investigates Hg concentrations in terrestrial songbirds of Southeast Michigan, where historical and present-day anthropogenic emissions of heavy metals are elevated. We collected tail feather samples from 223 songbirds across four different species during summer and fall of 2018 and 2019. The mean (±SE) Hg concentration across all samples was 103 ± 3.43 ng/g of dry feather weight. Mercury concentration varied significantly among species, and by age and site in some species, but not by sex. Mean concentrations were nearly seven times higher in two omnivore species, American robin (Turdus migratorius) and European starling (Sturnus vulgaris), than in the two granivore species, American goldfinch (Spinus tristus) and house sparrow (Passer domesticus). Juveniles had higher feather Hg concentrations than adults in all species except American goldfinches - which feed their young primarily seeds, further supporting a role of diet in exposure. We also found a negative correlation between Hg concentration and body condition in American robins, but further research is needed to verify this relationship. While our sample concentrations do not exceed the threshold for sublethal effects, our findings provide insight into the patterns of Hg concentrations in terrestrial songbirds, which may help in understanding Hg exposure pathways, bioaccumulation and risks in terrestrial species.
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Affiliation(s)
| | - Dorothy L Zahor
- Eastern Michigan University Biology Department, Ypsilanti, MI, 48197, USA
| | - Kenneth J Glynn
- Eastern Michigan University Biology Department, Ypsilanti, MI, 48197, USA
| | - Lynne E Gratz
- Colorado College Environmental Studies Program, Colorado Springs, CO, 80907, USA
| | - Jamie M Cornelius
- Eastern Michigan University Biology Department, Ypsilanti, MI, 48197, USA.
- Oregon State University Department of Integrative Biology, Corvallis, OR, 97331, USA.
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17
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Zhang F, Xu Z, Xu X, Liang L, Chen Z, Dong X, Luo K, Dinis F, Qiu G. Terrestrial mercury and methylmercury bioaccumulation and trophic transfer in subtropical urban forest food webs. CHEMOSPHERE 2022; 299:134424. [PMID: 35351481 DOI: 10.1016/j.chemosphere.2022.134424] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 06/14/2023]
Abstract
As the "lungs of the city", urban forests can improve air quality by absorbing air pollutants, becoming hotspots for mercury (Hg) pollution from anthropogenic activities. However, the bioaccumulation and transfer of Hg in the urban forest food web are unclear. In this study, total mercury (THg) and methylmercury (MeHg) concentrations, as well as the stable isotopes of carbon (δ13C) and nitrogen (δ15N) in organisms with different trophic levels (TLs) were investigated in a mid-subtropical urban forest of the Changpoling Forest Park (CFP) in Guiyang City, Guizhou Province, southwestern China. The results showed that THg and MeHg among all taxa ranged from 5.6 to 1267 ng g-1 and 0.046-692 ng g-1, respectively. MeHg% (% of Hg present as MeHg) at different TLs exhibited a wide range of 5.0-69% on average. Both THg and MeHg increased with the TLs from plants to nestling birds, indicating distinct biomagnification through the food web of grasses/pine needles - grasshoppers/caterpillars/katydids/mantis - spiders/songbird nestlings. The trophic magnification slope (TMS) of THg and MeHg were 0.18 ± 0.05 and 0.37 ± 0.08, respectively, suggesting both of them significantly increase along food webs. These findings improve the understanding of biogeochemical Hg cycles in terrestrial food webs and highlight the impacts of terrestrial MeHg on nestling birds.
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Affiliation(s)
- Fudong Zhang
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Xiaohang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; Key Laboratory of Karst Georesources and Environment, Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Longchao Liang
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Zhuo Chen
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China.
| | - Xian Dong
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Kang Luo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; Ailaoshan Station for Subtropical Forest Ecosystem Studies, Chinese Academy of Sciences, Jingdong, 676200, China
| | - Faustino Dinis
- College of Agriculture, Guizhou University, Guiyang, 550025, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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18
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Evans MN, Waller S, Müller CT, Goossens B, Smith JA, Bakar MSA, Kille P. The price of persistence: Assessing the drivers and health implications of metal levels in indicator carnivores inhabiting an agriculturally fragmented landscape. ENVIRONMENTAL RESEARCH 2022; 207:112216. [PMID: 34656630 DOI: 10.1016/j.envres.2021.112216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/17/2021] [Accepted: 10/11/2021] [Indexed: 06/13/2023]
Abstract
Patterns and practices of agricultural expansion threaten the persistence of global biodiversity. Wildlife species surviving large-scale land use changes can be exposed to a suite of contaminants that may deleteriously impact their health. There is a paucity of data concerning the ecotoxicological impacts associated with the global palm oil (Elaeis guineensis) industry. We sampled wild Malay civets (Viverra tangalunga) across a patchwork landscape degraded by oil palm agriculture in Sabah, Malaysian Borneo. Using a non-lethal methodology, we quantified the levels of 13 essential and non-essential metals within the hair of this adaptable small carnivore. We robustly assessed the biological and environmental drivers of intrapopulation variation in measured levels. Metal concentrations were associated with civet age, weight, proximity to a tributary, and access to oxbow lakes. In a targeted case study, the hair metal profiles of 16 GPS-collared male civets with differing space use patterns were contrasted. Civets that entered oil palm plantations expressed elevated aluminium, cadmium, and lead, and lower mercury hair concentrations compared to civets that remained exclusively within the forest. Finally, we paired hair metal concentrations with 34 blood-based health markers to evaluate the possible sub-lethal physiological effects associated with varied hair metal levels. Our multi-facetted approach establishes these adaptable carnivores as indicator species within an extensively altered ecosystem, and provides critical and timely evidence for future studies.
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Affiliation(s)
- Meaghan N Evans
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK; Danau Girang Field Centre, Kota Kinabalu, 88100, Malaysia.
| | - Simon Waller
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Carsten T Müller
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK
| | - Benoit Goossens
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK; Danau Girang Field Centre, Kota Kinabalu, 88100, Malaysia; Sustainable Places Institute, Cardiff University, Cardiff, CF10 3BA, UK; Sabah Wildlife Department, Kota Kinabalu, 88100, Malaysia
| | - Jeremy A Smith
- School of Applied Sciences, University of South Wales, CF37 4BB, UK
| | | | - Peter Kille
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK.
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19
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Gerson JR, Szponar N, Zambrano AA, Bergquist B, Broadbent E, Driscoll CT, Erkenswick G, Evers DC, Fernandez LE, Hsu-Kim H, Inga G, Lansdale KN, Marchese MJ, Martinez A, Moore C, Pan WK, Purizaca RP, Sánchez V, Silman M, Ury EA, Vega C, Watsa M, Bernhardt ES. Amazon forests capture high levels of atmospheric mercury pollution from artisanal gold mining. Nat Commun 2022; 13:559. [PMID: 35091543 PMCID: PMC8799693 DOI: 10.1038/s41467-022-27997-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 12/16/2021] [Indexed: 11/10/2022] Open
Abstract
Mercury emissions from artisanal and small-scale gold mining throughout the Global South exceed coal combustion as the largest global source of mercury. We examined mercury deposition and storage in an area of the Peruvian Amazon heavily impacted by artisanal gold mining. Intact forests in the Peruvian Amazon near gold mining receive extremely high inputs of mercury and experience elevated total mercury and methylmercury in the atmosphere, canopy foliage, and soils. Here we show for the first time that an intact forest canopy near artisanal gold mining intercepts large amounts of particulate and gaseous mercury, at a rate proportional with total leaf area. We document substantial mercury accumulation in soils, biomass, and resident songbirds in some of the Amazon's most protected and biodiverse areas, raising important questions about how mercury pollution may constrain modern and future conservation efforts in these tropical ecosystems.
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Affiliation(s)
- Jacqueline R Gerson
- Department of Biology, Duke University, Durham, NC, 27708, USA.
- Duke Global Health Institute, Duke University, Durham, NC, 27708, USA.
| | - Natalie Szponar
- Department of Earth Sciences, University of Toronto, Toronto, ON, M5S 3B1, Canada
| | | | - Bridget Bergquist
- Department of Earth Sciences, University of Toronto, Toronto, ON, M5S 3B1, Canada
| | - Eben Broadbent
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL, 32611, USA
| | - Charles T Driscoll
- Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Gideon Erkenswick
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Field Projects International, Escondido, CA, 92029, USA
| | - David C Evers
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Luis E Fernandez
- Centro de Innovación Científica Amazónica (CINCIA), Puerto Maldonado, Peru
- Center for Energy, Environment, and Sustainability (CEES), Wake Forest University, Winston-Salem, NC, 27109, USA
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Heileen Hsu-Kim
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708, USA
| | - Giancarlo Inga
- San Diego Zoo Wildlife Alliance, San Diego, CA, 92101, USA
| | - Kelsey N Lansdale
- Environmental Science Program, Duke University, Durham, NC, 27708, USA
| | - Melissa J Marchese
- Duke Global Health Institute, Duke University, Durham, NC, 27708, USA
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| | - Ari Martinez
- Department of Biological Sciences, California State University, Long Beach, CA, 90840, USA
| | - Caroline Moore
- San Diego Zoo Wildlife Alliance, San Diego, CA, 92101, USA
| | - William K Pan
- Duke Global Health Institute, Duke University, Durham, NC, 27708, USA
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, USA
| | | | - Victor Sánchez
- Instituto de Investigación en Ecología y Conservación (IIECOO), La Libertad, Peru
| | - Miles Silman
- Centro de Innovación Científica Amazónica (CINCIA), Puerto Maldonado, Peru
- Center for Energy, Environment, and Sustainability (CEES), Wake Forest University, Winston-Salem, NC, 27109, USA
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Emily A Ury
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Claudia Vega
- Centro de Innovación Científica Amazónica (CINCIA), Puerto Maldonado, Peru
- Center for Energy, Environment, and Sustainability (CEES), Wake Forest University, Winston-Salem, NC, 27109, USA
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Mrinalini Watsa
- Field Projects International, Escondido, CA, 92029, USA
- San Diego Zoo Wildlife Alliance, San Diego, CA, 92101, USA
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20
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Characteristics and impact of aged coal ash with slag emplaced in a karst cave: the case of Divaška jama, Slovenia. Sci Rep 2021; 11:23410. [PMID: 34862432 PMCID: PMC8642485 DOI: 10.1038/s41598-021-02842-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 11/16/2021] [Indexed: 11/08/2022] Open
Abstract
A mixture of coal bottom ash and slag, with a fraction of fly ash (CAFAS) from steam locomotives, was placed in the cave Divaška jama to delimit and level tourist trails. Emplacement began in 1914 and carried on for several decades. The CAFAS mixed with other cave material gradually changed its structure and appearance. Currently the concentration of some elements in the CAFAS (As, Cu, Hg, Ni, Pb, Zn), and also to a lesser extent in cave sediments (Cr, Cu, Ni), indicates a possibly harmful effect on sediment-associated biota based on ecotoxicological assays. Compared to the cave sediment, the CAFAS contains distinctly different mineral phases and presents a different source of radioactivity. Microbial metabolic activity of CAFAS is low, 0.22 μl O2/gDW h, but higher than that of cave sediment. The present environmental hazards from CAFAS are estimated to be low. Whereas the emplacement of CAFAS was seen initially a long-term solution for waste disposal and management of the cave, it turned out that CAFAS enriches the underground environment with inorganic and organic compounds and disperses pollution into the cave ecosystem. After its removal from the cave, the CAFAS should be investigated thoroughly due to its susceptibility to alteration.
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21
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Newsome L, Falagán C. The Microbiology of Metal Mine Waste: Bioremediation Applications and Implications for Planetary Health. GEOHEALTH 2021; 5:e2020GH000380. [PMID: 34632243 PMCID: PMC8490943 DOI: 10.1029/2020gh000380] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 08/17/2021] [Accepted: 08/20/2021] [Indexed: 05/13/2023]
Abstract
Mine wastes pollute the environment with metals and metalloids in toxic concentrations, causing problems for humans and wildlife. Microorganisms colonize and inhabit mine wastes, and can influence the environmental mobility of metals through metabolic activity, biogeochemical cycling and detoxification mechanisms. In this article we review the microbiology of the metals and metalloids most commonly associated with mine wastes: arsenic, cadmium, chromium, copper, lead, mercury, nickel and zinc. We discuss the molecular mechanisms by which bacteria, archaea, and fungi interact with contaminant metals and the consequences for metal fate in the environment, focusing on long-term field studies of metal-impacted mine wastes where possible. Metal contamination can decrease the efficiency of soil functioning and essential element cycling due to the need for microbes to expend energy to maintain and repair cells. However, microbial communities are able to tolerate and adapt to metal contamination, particularly when the contaminant metals are essential elements that are subject to homeostasis or have a close biochemical analog. Stimulating the development of microbially reducing conditions, for example in constructed wetlands, is beneficial for remediating many metals associated with mine wastes. It has been shown to be effective at low pH, circumneutral and high pH conditions in the laboratory and at pilot field-scale. Further demonstration of this technology at full field-scale is required, as is more research to optimize bioremediation and to investigate combined remediation strategies. Microbial activity has the potential to mitigate the impacts of metal mine wastes, and therefore lessen the impact of this pollution on planetary health.
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Affiliation(s)
- Laura Newsome
- Camborne School of Mines and Environment and Sustainability InstituteUniversity of ExeterPenrynUK
| | - Carmen Falagán
- Camborne School of Mines and Environment and Sustainability InstituteUniversity of ExeterPenrynUK
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22
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Ballová ZK, Janiga M, Holub M, Chovancová G. Temporal and seasonal changes in mercury accumulation in Tatra chamois from West Carpathians. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:52133-52146. [PMID: 34002309 DOI: 10.1007/s11356-021-14380-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 05/10/2021] [Indexed: 06/12/2023]
Abstract
The main aim of this study was to determine the concentration of total mercury (T-Hg) in different tissues, hair, and faeces from a long-lived animal that actively lives in the subalpine and alpine zone within temperate climate zone throughout the year. Levels of T-Hg in samples from naturally deceased Tatra chamois (n = 72) from the Tatra Mountains (Slovakia) were determined using direct mercury analyses on the basis of dry weight. The mercury concentrations in hair samples were compared over the last three decades. Seasonal changes in mercury concentration and differences in the amounts of mercury in various tissues, hairs, and faeces between age and sex groups were also studied. The highest mercury concentrations in organs were found in the kidneys of Tatra chamois, with mean values of 0.45 ± 0.07 μg/g (dry weight) for adults (n = 18) and 0.39 ± 0.12 μg/g (dry weight) for juveniles (n = 6). These values are considerably high compared to expected Hg levels in wild ungulates from foothill and mountain areas in the temperate zone. Juveniles had higher levels of T-Hg in their muscles (0.011 ± 0.001 μg/g dry weight, n = 10) and faeces (0.189 ± 0.025 μg/g dry weight, n = 7) when compared to adults that had 0.007 ± 0.001 μg/g dry weight of T-Hg in muscles (n = 29) and 0.113 ± 0.015 μg/g dry of T-Hg weight in faeces (n = 19). T-Hg concentrations in individual tissues (heart, kidney, liver, lungs, spleen, tongue, muscle, bone), hairs, and faeces were not significantly different between males and females. Mercury levels in the hair of Tatra chamois have increased significantly since the 1990s (median value of T-Hg: 0.025 μg/g dry weight) with the highest values presenting during the 2000s (0.029 μg/g dry weight). Since 2010 (0.016 μg/g dry weight), levels have declined when compared to those observed during the 1990s and 2000s. Therefore, we can conclude that T-Hg deposition in alpine areas of the Tatra Mountains shows a declining trend since the 2010s. T-Hg concentrations in the heart, muscle, and hair were higher in summer compared to winter. Seasonal changes in mercury concentrations are likely most related to the seasonal availability of food, but may also be related to moulting periods, and this correlation must be explored further.
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Affiliation(s)
- Zuzana Kompišová Ballová
- Institute of High Mountain Biology, University of Žilina, Tatranská Javorina 7, 05956, Tatranská Javorina, Slovakia.
| | - Marián Janiga
- Institute of High Mountain Biology, University of Žilina, Tatranská Javorina 7, 05956, Tatranská Javorina, Slovakia
| | - Marek Holub
- Institute of High Mountain Biology, University of Žilina, Tatranská Javorina 7, 05956, Tatranská Javorina, Slovakia
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23
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Li C, Xu Z, Luo K, Chen Z, Xu X, Xu C, Qiu G. Biomagnification and trophic transfer of total mercury and methylmercury in a sub-tropical montane forest food web, southwest China. CHEMOSPHERE 2021; 277:130371. [PMID: 34384195 DOI: 10.1016/j.chemosphere.2021.130371] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/16/2021] [Accepted: 03/20/2021] [Indexed: 06/13/2023]
Abstract
Little is known about the bioaccumulation and trophic transfer of total mercury (THg) and methylmercury (MeHg) via food webs in terrestrial ecosystems, especially in subtropical forest ecosystems. In the present study, THg and MeHg were determined as well as the carbon (δ13C) and nitrogen (δ15N) isotope composition in samples of soils, plants, invertebrates, and songbird feathers to construct food webs in a remote subtropical montane forest in Mt. Ailao, southwest China and assess the bioaccumulation, biomagnification, and trophic transfer of Hg. Results showed that the trophic levels (TLs) of all consumers ranged from 0.8 to 3.3 and followed the order of songbirds > spiders > omnivorous insects > herbivorous insects > plants, and THg and MeHg exhibited a clear biomagnification up the food chain from plants-herbivorous/omnivorous insects-spiders-songbirds. The lowest MeHg concentration was observed in pine needles ranged from 0.104 to 0.949 ng g-1 with only a 1.6% ratio of MeHg to THg (MeHg%), while the highest MeHg concentrations ranged from 425 to 5272 ng g-1 in songbirds with MeHg% values of up to 96%. High values of trophic magnification slope (TMS) for THg (0.22) and MeHg (0.38) were observed in plant-invertebrate-songbird food chain, verifying the significant bioaccumulation of Hg, particularly MeHg, in the remote subtropical forest ecosystem. This study confirmed the production and efficient biomagnification of MeHg in remote subtropical montane forest and the significant bioaccumulation of MeHg in terrestrial top predators.
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Affiliation(s)
- Chan Li
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kang Luo
- Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna, 666303, China; CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna, 666303, China; Ailaoshan Station for Subtropical Forest Ecosystem Studies, Chinese Academy of Sciences, Jingdong, 676200, China
| | - Zhuo Chen
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China.
| | - Xiaohang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chengxiang Xu
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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24
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Webster AM, Cleckner LB, Razavi NR. Mercury Concentrations in Big Brown Bats (Eptesicus fuscus) of the Finger Lakes Region, New York. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 81:1-14. [PMID: 33796893 DOI: 10.1007/s00244-021-00839-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
The northeastern United States receives elevated mercury (Hg) deposition from United States and global emissions, making it critical to understand the fate of Hg in watersheds with a variety of aquatic habitats and land use types, such as the Finger Lakes region of New York State. Bats are valuable and important organisms to study chronic Hg exposure, because they are at risk of sublethal effects from elevated Hg exposure. The objectives of this study were to: (1) determine total Hg (THg) and methylmercury (MeHg) concentrations in big brown bats (Eptesicus fuscus) of the Finger Lakes region; (2) assess whether morphometric, temporal, or spatial factors predict bat Hg concentrations; and (3) investigate the role of trophic position and diet represented by stable isotopes of carbon and nitrogen in explaining variations in bat Hg concentrations. We found comparable THg and MeHg concentrations to previous studies (THg range 1-45 ppm, MeHg range 0.5-38 ppm) in big brown bat fur collected throughout the Finger Lakes region. On average, MeHg made up 81% of THg in bat fur. Fifteen percent of our samples showed higher THg than a proposed toxicity threshold of 10 ppm. Together, dominant land cover and % wetland cover explained bat THg in the Finger Lakes. Trophic position (i.e., δ15N) was strongest in predicting bat THg in forests but was a weaker predictor of Hg bioaccumulation in bats from agricultural and urban areas. The range of Hg concentrations found in this study warrants further examination into the potential toxicological impacts of Hg to wildlife and the role of land use in Hg exposure to terrestrial organisms of the Finger Lakes.
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Affiliation(s)
- Abby M Webster
- Department of Environmental Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA.
| | - Lisa B Cleckner
- Finger Lakes Institute, Hobart and William Smith Colleges, Geneva, NY, 14556, USA
| | - N Roxanna Razavi
- Department of Environmental Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
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25
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Bottini CLJ, MacDougall-Shackleton SA, Branfireun BA, Hobson KA. Feathers accurately reflect blood mercury at time of feather growth in a songbird. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 775:145739. [PMID: 33621875 DOI: 10.1016/j.scitotenv.2021.145739] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/04/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
Methylmercury (MeHg) is a globally distributed pollutant that can negatively affect wildlife. Bird feathers are often used as a monitoring tool of contaminant exposure, but variability in total mercury (THg) content in flight feathers has raised concerns over their utility. The objective of this study was to quantify blood and feather THg depuration through the progression of primary feather molt in order to clarify the relationship between blood and feather mercury concentration, and test the reliability of feather THg measurements as a monitoring tool in wild songbirds. Song sparrows (Melospiza melodia) were experimentally exposed to dietary MeHg and their blood and primary feather THg concentrations were measured during exposure and post-exposure periods of three months each. A rapid decrease in feather and blood THg concentration through molt progression was observed. Primary feather THg content was higher in feathers grown during the MeHg exposure period compared to those grown during the post-exposure period. Primary feather THg concentration was highly correlated with blood THg measured at the time of feather growth (R = 0.98), indicating that, although THg concentration is variable among flight feathers, this reflects temporally sequential molting patterns and declining blood concentration during depuration. Primary flight feathers thus provide an accurate and useful tool for estimating the mercury burden of birds at the time a chosen feather was grown, and have the potential to be an effective and reliable biomonitoring tool for species with well-characterized molt patterns.
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Affiliation(s)
- Claire L J Bottini
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada.
| | - Scott A MacDougall-Shackleton
- Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada; The University of Western Ontario, Department of Psychology, 1151 Richmond St., London, Ontario, N6A 5C2, Canada
| | - Brian A Branfireun
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Centre for Environment and Sustainability, University of Western Ontario, London, Ontario, Canada
| | - Keith A Hobson
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada
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26
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Christakis CA, Barkay T, Boyd ES. Expanded Diversity and Phylogeny of mer Genes Broadens Mercury Resistance Paradigms and Reveals an Origin for MerA Among Thermophilic Archaea. Front Microbiol 2021; 12:682605. [PMID: 34248899 PMCID: PMC8261052 DOI: 10.3389/fmicb.2021.682605] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/28/2021] [Indexed: 11/13/2022] Open
Abstract
Mercury (Hg) is a highly toxic element due to its high affinity for protein sulfhydryl groups, which upon binding, can destabilize protein structure and decrease enzyme activity. Prokaryotes have evolved enzymatic mechanisms to detoxify inorganic Hg and organic Hg (e.g., MeHg) through the activities of mercuric reductase (MerA) and organomercury lyase (MerB), respectively. Here, the taxonomic distribution and evolution of MerAB was examined in 84,032 archaeal and bacterial genomes, metagenome assembled genomes, and single-cell genomes. Homologs of MerA and MerB were identified in 7.8 and 2.1% percent of genomes, respectively. MerA was identified in the genomes of 10 archaeal and 28 bacterial phyla previously unknown to code for this functionality. Likewise, MerB was identified in 2 archaeal and 11 bacterial phyla previously unknown to encode this functionality. Surprisingly, homologs of MerB were identified in a number of genomes (∼50% of all MerB-encoding genomes) that did not encode MerA, suggesting alternative mechanisms to detoxify Hg(II) once it is generated in the cytoplasm. Phylogenetic reconstruction of MerA place its origin in thermophilic Thermoprotei (Crenarchaeota), consistent with high levels of Hg(II) in geothermal environments, the natural habitat of this archaeal class. MerB appears to have been recruited to the mer operon relatively recently and likely among a mesophilic ancestor of Euryarchaeota and Thaumarchaeota. This is consistent with the functional dependence of MerB on MerA and the widespread distribution of mesophilic microorganisms that methylate Hg(II) at lower temperature. Collectively, these results expand the taxonomic and ecological distribution of mer-encoded functionalities, and suggest that selection for Hg(II) and MeHg detoxification is dependent not only on the availability and type of mercury compounds in the environment but also the physiological potential of the microbes who inhabit these environments. The expanded diversity and environmental distribution of MerAB identify new targets to prioritize for future research.
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Affiliation(s)
- Christos A. Christakis
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Tamar Barkay
- Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Eric S. Boyd
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
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27
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Carvalho GOD, Meire RO, Lino AS, Yogui DR, Desbiez ALJ, Torres JPM, Malm O. Biomonitoring mercury contamination using fur from roadkilled giant anteaters. CHEMOSPHERE 2021; 270:128644. [PMID: 33121800 DOI: 10.1016/j.chemosphere.2020.128644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 10/04/2020] [Accepted: 10/13/2020] [Indexed: 06/11/2023]
Abstract
The giant anteater (Myrmecophaga tridactyla) can occur in both preserved and anthropogenic environments in Brazilian biomes. The Cerrado biome, where the samples were collected, is considered one of the world's biodiversity hotspots; however, a large part of it has been converted to pasture and agricultural land. In this environment, animals may be exposed to contaminants, such as mercury (Hg). Despite its immense biodiversity, there are few studies investigating Hg contamination in terrestrial mammals in Brazil. This study aimed to create a baseline for Hg levels in giant anteater fur and establish which biotic and abiotic variables can influence its concentration. Total Hg (THg) concentrations were determined by cold vapor atomic absorption spectrometry in 141 individuals sampled on highways between January and October 2017, in the state of Mato Grosso do Sul, Brazil. THg concentrations in fur ranged from 0.27 to 4.77 μg g -1. The decomposition stage of the carcasses and vehicular traffic volume on highways did not influence the THg concentrations. Juveniles presented lower THg concentrations than adults. A spatial pattern of higher concentrations in the eastern-southeastern region of the state was found, which could be related to anthropogenic impacts; however, no clear links have been established. The THg concentrations in giant anteaters' fur seems higher than expected considering the trophic position of the species. Despite this, the range was in accordance with studies of other Brazilian terrestrial mammals and within safe threshold levels. This study indicates the potential of utilizing roadkilled fauna to monitor large-scale contamination in wildlife.
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Affiliation(s)
- Gabriel Oliveira de Carvalho
- Laboratório de Radioisótopos Eduardo Penna Franca, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro (UFRJ), Avenida Carlos Chagas Filho, 373 - Bloco G - Subsolo - Sala G061, Cidade Universitária, CEP 21941-902, Rio de Janeiro, Brazil; SAGE - Núcleo Professor Rogério Valle de Produção Sustentável, Universidade Federal Do Rio de Janeiro (UFRJ), COPPE/UFRJ, Centro de Gestão Tecnológica - CT2 - Rua Moniz de Aragão, No.360 - Bloco 2, Ilha Do Fundão - Cidade Universitária, Rio de Janeiro, Brazil.
| | - Rodrigo Ornellas Meire
- Laboratório de Radioisótopos Eduardo Penna Franca, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro (UFRJ), Avenida Carlos Chagas Filho, 373 - Bloco G - Subsolo - Sala G061, Cidade Universitária, CEP 21941-902, Rio de Janeiro, Brazil
| | - Adan Santos Lino
- Laboratório de Radioisótopos Eduardo Penna Franca, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro (UFRJ), Avenida Carlos Chagas Filho, 373 - Bloco G - Subsolo - Sala G061, Cidade Universitária, CEP 21941-902, Rio de Janeiro, Brazil
| | - Débora Regina Yogui
- Instituto de Conservação de Animais Silvestres, Rua Afonso Lino Barbosa, 142, Chácara Cachoeira, Campo Grande, MS, CEP: 79040-290, Brazil; Nashville Zoo, 3777 Nolensville Pike, Nashville, TN, 37211, USA
| | - Arnaud Léonard Jean Desbiez
- Instituto de Conservação de Animais Silvestres, Rua Afonso Lino Barbosa, 142, Chácara Cachoeira, Campo Grande, MS, CEP: 79040-290, Brazil; The Royal Zoological Society of Scotland, Edinburgh Zoo, 134 Corstorphine Road, Edinburgh, EH12 6TS, United Kingdom
| | - João Paulo Machado Torres
- Laboratório de Radioisótopos Eduardo Penna Franca, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro (UFRJ), Avenida Carlos Chagas Filho, 373 - Bloco G - Subsolo - Sala G061, Cidade Universitária, CEP 21941-902, Rio de Janeiro, Brazil
| | - Olaf Malm
- Laboratório de Radioisótopos Eduardo Penna Franca, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro (UFRJ), Avenida Carlos Chagas Filho, 373 - Bloco G - Subsolo - Sala G061, Cidade Universitária, CEP 21941-902, Rio de Janeiro, Brazil
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Levin D, Raab N, Pinto Y, Rothschild D, Zanir G, Godneva A, Mellul N, Futorian D, Gal D, Leviatan S, Zeevi D, Bachelet I, Segal E. Diversity and functional landscapes in the microbiota of animals in the wild. Science 2021; 372:science.abb5352. [PMID: 33766942 DOI: 10.1126/science.abb5352] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 07/17/2020] [Accepted: 03/09/2021] [Indexed: 12/11/2022]
Abstract
Animals in the wild are able to subsist on pathogen-infected and poisonous food and show immunity to various diseases. These may be due to their microbiota, yet we have a poor understanding of animal microbial diversity and function. We used metagenomics to analyze the gut microbiota of more than 180 species in the wild, covering diverse classes, feeding behaviors, geographies, and traits. Using de novo metagenome assembly, we constructed and functionally annotated a database of more than 5000 genomes, comprising 1209 bacterial species of which 75% are unknown. The microbial composition, diversity, and functional content exhibit associations with animal taxonomy, diet, activity, social structure, and life span. We identify the gut microbiota of wild animals as a largely untapped resource for the discovery of therapeutics and biotechnology applications.
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Affiliation(s)
| | | | | | - Daphna Rothschild
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, 7610001 Israel.,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 7610001, Israel.,Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA.,Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | | | - Anastasia Godneva
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, 7610001 Israel.,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | | | | | | | - Sigal Leviatan
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, 7610001 Israel.,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - David Zeevi
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, 7610001 Israel.,Center for Studies in Physics and Biology, Rockefeller University, New York, NY 10065, USA
| | - Ido Bachelet
- Wild Biotech, Rehovot, Israel.,Augmanity, Rehovot, Israel
| | - Eran Segal
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, 7610001 Israel. .,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
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29
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Sullivan SMP, Corra JW, Hayes JT. Urbanization mediates the effects of water quality and climate on a model aerial insectivorous bird. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1442] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- S. Mažeika P. Sullivan
- Schiermeier Olentangy River Wetland Research Park School of Environment & Natural Resources The Ohio State University 2021 Coffey Road Columbus Ohio43210USA
| | - Joseph W. Corra
- Schiermeier Olentangy River Wetland Research Park School of Environment & Natural Resources The Ohio State University 2021 Coffey Road Columbus Ohio43210USA
| | - Jeffry T. Hayes
- Schiermeier Olentangy River Wetland Research Park School of Environment & Natural Resources The Ohio State University 2021 Coffey Road Columbus Ohio43210USA
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30
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Dahmardeh Behrooz R, Poma G. Evaluation of Mercury Contamination in Iranian Wild Cats Through Hair Analysis. Biol Trace Elem Res 2021; 199:166-172. [PMID: 32306286 DOI: 10.1007/s12011-020-02148-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 04/07/2020] [Indexed: 11/24/2022]
Abstract
Due to its environmental persistence and bioaccumulative properties, mercury is considered highly toxic to humans, ecosystems, and wildlife. The present study aimed to investigate the total mercury (Hg) concentrations in hair samples of 40 wild cats belonging to eight different species collected from various provinces of Iran and to characterize their risk of Hg exposure. Total Hg levels in Iranian wild cats ranged from 62 to 3670 ng/g dw hair, with a median value of 488 ng/g dw hair. The lowest median Hg concentration was found in west Iran (251 ng/g dw hair), while the highest median level was measured in the north-east of the country (736 ng/g dw hair), likely related to its past use in agriculture and potential contamination of industrial effluents. The overall contamination of Iranian wild cats with mercury can be considered generally low, but 20% of the samples reached levels above 1100 ng/g dw hair, set as indicative of an environmental Hg concern according to the U.S. Fish and Wildlife Service. Our data are comparable with other investigations on wildlife worldwide, confirming the suitability of museum collection specimens to assess the environmental levels of Hg. We showed that, while diet and habitat can influence the mercury accumulation in wild cats, complementary factors, such as age, size, and interspecific metabolic differences, should be considered as well in future investigations.
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Affiliation(s)
- Reza Dahmardeh Behrooz
- Department of Environmental Sciences, Faculty of Natural Resources, University of Zabol, Zabol, Sistan, Iran.
| | - Giulia Poma
- Toxicological Centre, University of Antwerp, 2610, Wilrijk, Belgium
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31
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Sauer AK, Driscoll CT, Evers DC, Adams EM, Yang Y. Mercury exposure in songbird communities along an elevational gradient on Whiteface Mountain, Adirondack Park (New York, USA). ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1830-1842. [PMID: 32232628 DOI: 10.1007/s10646-020-02175-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/07/2020] [Indexed: 06/10/2023]
Abstract
Mercury (Hg) is a potent neurotoxin that biomagnifies within food webs. Adverse effects have been documented for avian species related to exposure of elevated Hg levels. High elevation, boreal forests generally receive higher atmospheric Hg deposition and regional studies have subsequently identified elevated blood Hg concentrations in songbird species inhabiting these montane habitats. The overall goal of this study was to investigate spatial and seasonal Hg exposure patterns in songbird species along an elevational gradient on Whiteface Mountain in the Adirondack Park of New York State. Songbird blood samples were collected from June-July in 2009 and 2010 along an elevational gradient at 13 study plots (450-1400 m) with a focus on Catharus thrushes, including the hermit thrush, Swainson's thrush, and Bicknell's thrush. The main results of this study documented: (1) an overall linear pattern of increasing blood Hg concentrations with increasing elevation, with additional analysis suggesting a nonlinear elevational pattern of increasing blood Hg concentrations to 1075 m, followed by decreasing concentrations thereafter, for all Catharus thrush species across the elevational gradient; and (2) an overall nonlinear seasonal pattern of increasing, followed by decreasing blood Hg concentrations across target species. Avian exposure patterns appear driven by elevated atmospheric Hg deposition and increased methylmercury bioavailability within high elevation habitats as compared with low elevation forests. Seasonal patterns are likely influenced by a combination of complex and dynamic variables related to dietary selection and annual molting cycles. Considering that few high elevation analyses have been conducted within the context of regional songbird research, this project complements the results from similar studies and highlights the need for further monitoring efforts to investigate environmental Hg contamination within avian communities.
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Affiliation(s)
- Amy K Sauer
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA.
- Department of Biology, Syracuse University, Syracuse, NY, 13244, USA.
| | - Charles T Driscoll
- Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Evan M Adams
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Yang Yang
- Department of Forest and Natural Resources Management, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
- Sierra Nevada Research Institute, University of California Merced, Merced, CA, 95340, USA
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32
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Sauer AK, Driscoll CT, Evers DC, Adams EM, Yang Y. Mercury exposure in songbird communities within Sphagnum bog and upland forest ecosystems in the Adirondack Park (New York, USA). ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1815-1829. [PMID: 32037482 DOI: 10.1007/s10646-019-02142-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/24/2019] [Indexed: 06/10/2023]
Abstract
Mercury (Hg) is a potent neurotoxin that biomagnifies within both aquatic and terrestrial food webs resulting in adverse physiological and reproductive effects on impacted wildlife populations, including songbird communities. Due to reducing conditions, wetland ecosystems promote the formation of methylmercury. Regional studies have documented elevated blood mercury concentrations in songbird species within these habitat types. The overall goal of this research was to examine spatial and seasonal patterns of Hg exposure for targeted songbird species within Sphagnum bog wetland systems and compare these patterns with adjacent upland forests in the Adirondack Park of New York State. Project sampling was conducted at study plots within four Sphagnum bog and associated upland forest sites from May - August during the 2008, 2009, and 2011 field seasons. The overall results documented: (1) blood Hg concentrations were elevated in songbird species inhabiting Sphagnum bog habitats as compared to nearby upland forest species; (2) target species within each habitat type exhibited consistent species-level patterns in blood Hg concentrations at each study site; and (3) no seasonal change in blood Hg concentrations within Sphagnum bog habitats was documented, but an increasing, followed by a decreasing seasonal pattern in mercury exposure was detected for upland forest species. Habitat type was demonstrated to influence avian Hg exposure levels. Moreover, Sphagnum bog ecosystems may be contributing to elevated Hg concentrations in biota within the surrounding environment. Seasonal patterns for blood Hg concentrations were found to vary between habitat type and are likely related to a combination of variables including habitat-driven Hg concentrations in prey items, seasonal dietary shifts, and annual molting cycles. This project emphasizes the importance of prioritizing future research efforts within identified high Hg habitat types, specifically wetland systems, to better characterize associated avian exposure levels, estimate the spatial extent of wetland systems on the surrounding environment, and identify locations of potential biological hotspots across the Adirondack Park.
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Affiliation(s)
- Amy K Sauer
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA.
- Department of Biology, Syracuse University, Syracuse, NY, 13244, USA.
| | - Charles T Driscoll
- Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Evan M Adams
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Yang Yang
- Department of Forest and Natural Resources Management, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
- Sierra Nevada Research Institute, University of California Merced, Merced, CA, 95340, USA
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33
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DeSorbo CR, Burgess NM, Nye PE, Loukmas JJ, Brant HA, Burton MEH, Persico CP, Evers DC. Bald eagle mercury exposure varies with region and site elevation in New York, USA. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1862-1876. [PMID: 31925622 DOI: 10.1007/s10646-019-02153-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
Freshwater fish in several regions of New York State (NYS) are known to contain concentrations of mercury (Hg) associated with negative health effects in wildlife and humans. We collected blood and breast feathers from bald eagle (Haliaeetus leucocephalus) nestlings throughout NYS, with an emphasis on the Catskill region to determine their exposure to Hg. We assessed whether habitat type (lake or river), region (Delaware-Catskill region vs. rest of NY) or sample site elevation influenced Hg concentrations in bald eagle breast feathers using ANCOVA. The model was significant and accounted for 41% of the variability in log10 breast feather Hg concentrations. Mercury concentrations in nestling breast feathers were significantly greater in the Delaware-Catskill Region (geometric mean: 14.5 µg/g dw) than in the rest of NY (7.4 µg/g, dw), and greater at nests located at higher elevations. Habitat type (river vs. lake) did not have a significant influence on breast feather Hg concentrations. Geometric mean blood Hg concentrations were significantly greater in Catskill nestlings (0.78 µg/g ww) than in those from the rest of NY (0.32 µg/g). Mercury concentrations in nestling breast feathers and especially blood samples from the Delaware-Catskill region were generally greater than those reported for most populations sampled elsewhere, including areas associated with significant Hg pollution problems. Bald eagles can serve as valuable Hg bioindicators in aquatic ecosystems of NYS, particularly given their broad statewide distribution and their tendency to nest across all major watersheds and different habitat types.
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Affiliation(s)
- C R DeSorbo
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA.
| | - N M Burgess
- Environment & Climate Change Canada, 6 Bruce Street, Mount Pearl, NL, A1N 4T3, Canada
| | - P E Nye
- New York State Department of Environmental Conservation, 625 Broadway, Albany, NY, 12233-4753, USA
- 1926 Tarrytown Rd., Feura Bush, NY, 12067, USA
| | - J J Loukmas
- New York State Department of Environmental Conservation, 625 Broadway, Albany, NY, 12233-4753, USA
| | - H A Brant
- Savannah River National Laboratory, Aiken, SC, USA
| | - M E H Burton
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - C P Persico
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - D C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
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34
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Canova L, Sturini M, Profumo A, Maraschi F. Evidence of Low-Habitat Contamination Using Feathers of Three Heron Species as a Biomonitor of Inorganic Elemental Pollution. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E7776. [PMID: 33114248 PMCID: PMC7660610 DOI: 10.3390/ijerph17217776] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/19/2020] [Accepted: 10/21/2020] [Indexed: 12/14/2022]
Abstract
The concentration of 12 elements (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) has been investigated in the feathers of three species of Ardeidae, namely the Grey Heron Ardea cinerea, the Little Egret Egretta garzetta, and the Cattle Egret Bubulcus ibis, all breeding at a colony located in the southern Padana Plain (NW Italy). This study is a first step for an evaluation of possible direct effects of these elements on chicks' survival and growth rate. Fe, Zn, Cu, and Mn were in the range 7-69 mg Kg-1, while lower levels of Pb, Ni, As, and Se (0.27-1.45 mg Kg-1) were measured. Co, Cd, and Cr were close to the method detection limits (MDLs) in all the species. The measured concentrations of the most abundant trace elements, such as Zn and Cu, seem to reflect the geochemical pattern of the background (running water and soil), while Hg concentration is lower and it appears to be biomagnified, particularly in Grey Heron feathers. Its concentration is higher in adults than in chicks, and it differs among the three species, as it is closely related to the fish-based dietary pattern. The measured trace elements' concentrations are below the threshold levels in all the heron species, and consequently, harmful and acute effects on the local population are unlikely; the conservation status of herons populations in northern Italy is probably more affected by other factors, such as climate changes, altered aquatic environment, and, consequently, food quality.
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Affiliation(s)
- Luca Canova
- Department of Chemistry, University of Pavia, I-27100 Pavia, Italy; (M.S.); (A.P.); (F.M.)
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35
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Rimmer CC, Lloyd JD, McFarland KP, Evers DC, Lane OP. Patterns of blood mercury variation in two long-distance migratory thrushes on Mount Mansfield, Vermont. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1174-1182. [PMID: 31520201 DOI: 10.1007/s10646-019-02104-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
We investigated mercury (Hg) blood concentrations in Bicknell's thrush (Catharus bicknelli) and Swainson's thrush (C. ustulatus), congeneric long-distance migratory songbirds, from 2000-2017 at a montane forest site in north-central Vermont. We analyzed variation in blood Hg of both species using mixed-effects models, incorporating atmospheric wet Hg deposition data from a nearby sampling location. Although Hg deposition varied among years and seasonally, we detected no temporal trend in either atmospheric deposition or blood Hg, nor evidence of a relationship between the two. Sampling date had the strongest effect on blood Hg concentration, which declined seasonally, followed by age and sex of the individual. The data did not support an effect of species. We believe that the absence of a clear relationship between local atmospheric deposition and thrush blood Hg concentrations suggests that Hg cycling dynamics, mechanisms of transfer, and timing of uptake by montane forest biota are complex and poorly understood. The blood Hg concentrations of ~0.07-0.1 μg/g we documented in Bicknell's and Swainson's thrush are below those found to negatively impact physiological or reproductive endpoints in other invertivorous terrestrial passerines. To better evaluate the validity of Bicknell's thrush as a bioindicator of MeHg availability in montane forest ecosystems, we recommend (1) effects-based investigations, (2) a more robust understanding of Hg and MeHg cycling, (3) more clear geospatial and temporal links between Hg deposition and biotic uptake, and (4) more thorough documentation of Hg burdens across the species' annual cycle.
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Affiliation(s)
| | - John D Lloyd
- Vermont Center for Ecostudies, P.O. Box 420, Norwich, VT, 05055, USA
- American Wind Wildlife Institute, 1990 K Street NW, Suite 620, Washington, DC, 20006, USA
| | - Kent P McFarland
- Vermont Center for Ecostudies, P.O. Box 420, Norwich, VT, 05055, USA
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Oksana P Lane
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
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36
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Seewagen CL. The threat of global mercury pollution to bird migration: potential mechanisms and current evidence. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1254-1267. [PMID: 30159636 DOI: 10.1007/s10646-018-1971-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
Mercury is a global pollutant that has been widely shown to adversely affect reproduction and other endpoints related to fitness and health in birds, but almost nothing is known about its effects on migration relative to other life cycle processes. Here I consider the physiological and histological effects that mercury is known to have on non-migrating birds and non-avian vertebrates to identify potential mechanisms by which mercury might hinder migration performance. I posit that the broad ability of mercury to inactivate enzymes and compromise the function of other proteins is a single mechanism by which mercury has strong potential to disrupt many of the physiological processes that make long-distance migration possible. In just this way alone, there is reason to expect mercury to interfere with navigation, flight endurance, oxidative balance, and stopover refueling. Navigation and flight could be further affected by neurotoxic effects of mercury on the brain regions that process geomagnetic information from the visual system and control biomechanics, respectively. Interference with photochemical reactions in the retina and decreases in scotopic vision sensitivity caused by mercury also have the potential to disrupt visual-based magnetic navigation. Finally, migration performance and possibly survival might be limited by the immunosuppressive effects of mercury on birds at a time when exposure to novel pathogens and parasites is great. I conclude that mercury pollution is likely to be further challenging what is already often the most difficult and perilous phase of a migratory bird's annual cycle, potentially contributing to global declines in migratory bird populations.
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Affiliation(s)
- Chad L Seewagen
- Great Hollow Nature Preserve & Ecological Research Center, 225 Route 37, New Fairfield, CT, USA.
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37
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Stenhouse IJ, Adams EM, Phillips LM, Weidensaul S, McIntyre CL. A preliminary assessment of mercury in the feathers of migratory songbirds breeding in the North American subarctic. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1221-1228. [PMID: 31531800 DOI: 10.1007/s10646-019-02105-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
Passerines appear to have a greater sensitivity to mercury than other avian orders, and little data exists for mercury exposure in songbirds breeding at high latitudes. In this preliminary study, we examined mercury exposure in 12 migratory songbird species breeding in Denali National Park & Preserve, in subarctic interior Alaska. Overall, we analyzed 343 feather samples collected in 2015-2017 for their total mercury content. Mercury levels found in feathers indicates exposure during the period of feather growth, which we assume largely took place on the breeding ground. In this limited sample of songbird feathers, mercury concentrations ranged from near zero to 6.34 μg/g. Most species sampled showed relatively low mercury, but some individuals had high enough concentrations to be subject to adverse physiological and behavioral effects. There was an indication that mercury concentrations of breeding songbirds may vary by diet composition, with non-invertivorous species possibly tending towards lower mercury concentrations. Overall, however, the degree of mercury exposure observed was low for songbirds breeding in the subarctic. Further examination would prove useful in clarifying mercury exposure and ecological relationships in this under-studied region.
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Affiliation(s)
| | - E M Adams
- Biodiversity Research Institute, Portland, ME, USA
| | - L M Phillips
- National Park Service, Denali National Park & Preserve, Denali Park, AK, USA
| | | | - C L McIntyre
- National Park Service, Denali National Park & Preserve, Fairbanks, AK, USA
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38
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Knutsen CJ, Varian-Ramos CW. Explaining variation in Colorado songbird blood mercury using migratory behavior, foraging guild, and diet. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1268-1280. [PMID: 31811508 DOI: 10.1007/s10646-019-02141-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/23/2019] [Indexed: 06/10/2023]
Abstract
Methylmercury is a contaminant of growing global concern that has been shown to accumulate in a variety of taxa, including songbirds. Birds in the same area can accumulate mercury to strikingly different levels. While diet and trophic level clearly play an important role in mercury bioaccumulation and biomagnification, other factors including foraging guilds and migratory behavior may influence mercury levels as well. Here we examine interspecific variation in blood mercury levels in songbirds living in the Fountain Creek watershed on the Front Range of Colorado. We found that the species with the highest mercury had blood mercury concentrations over 75 times higher than the species with the lowest levels. Carnivores had the highest blood mercury levels, but ground foraging and long distance migration also were correlated with higher mercury concentrations. This information may shed light on what species are most at risk from mercury pollution and help to target conservation resources at contaminated sites.
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Affiliation(s)
- Carley J Knutsen
- Biology Department, Colorado State University-Pueblo, 2200 Bonforte Blvd., Pueblo, CO, 81001, USA
| | - Claire W Varian-Ramos
- Biology Department, Colorado State University-Pueblo, 2200 Bonforte Blvd., Pueblo, CO, 81001, USA.
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39
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Perkins M, Lane OP, Evers DC, Sauer A, Adams EM, O'Driscoll NJ, Edmunds ST, Jackson AK, Hagelin JC, Trimble J, Sunderland EM. Historical patterns in mercury exposure for North American songbirds. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1161-1173. [PMID: 31161526 DOI: 10.1007/s10646-019-02054-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/09/2019] [Indexed: 06/09/2023]
Abstract
Methylmercury (MeHg) is a global environmental contaminant that poses significant risks to the health of humans, wildlife, and ecosystems. Assessing MeHg exposure in biota across the landscape and over time is vital for monitoring MeHg pollution and gauging the effectiveness of regulations intended to reduce new mercury (Hg) releases. We used MeHg concentrations measured in museum specimen feathers (collected between 1869 and 2014) and total Hg concentrations (as a proxy for MeHg) of feathers sampled from wild birds (collected between 2008 and 2017) to investigate temporal patterns in exposure over approximately 150 years for North American songbirds. For individual species, we found greater concentrations for samples collected post-2000 compared to those collected during historic times (pre-1900) for six of seven songbird species. Mean feather concentrations measured in samples collected post-2000 ranged between 1.9 and 17 times (mean 6.6) greater than historic specimens. The proportion of individual songbirds with feather concentrations that exceeded modeled toxicity benchmarks increased in samples collected after 1940. Only 2% of individual songbirds collected prior to 1940 had feather concentrations greater than 2.4 μg/g (a toxicity benchmark related to a 10% decrease in nest success) compared to 35% of individuals collected post-1940. Many species included in this study have a vulnerable or near-threatened conservation status, suggesting recovery actions are needed to address mercury pollution.
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Affiliation(s)
- Marie Perkins
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
| | - Oksana P Lane
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - David C Evers
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Amy Sauer
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Evan M Adams
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Nelson J O'Driscoll
- K. C. Irving Environmental Science Centre, Department of Earth and Environmental Sciences, Acadia University, Wolfville, NS, B4P 2R6, Canada
| | | | - Allyson K Jackson
- Department of Environmental Studies, Purchase College, SUNY, Purchase, NY, 10577, USA
| | - Julie C Hagelin
- Alaska Department of Fish and Game, Threatened, Endangered and Diversity Program, Fairbanks, AK, 99701, USA
| | - Jeremiah Trimble
- Museum of Comparative Zoology, Harvard University, Cambridge, MA, 02138, USA
| | - Elsie M Sunderland
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
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40
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Lane O, Adams EM, Pau N, O'Brien KM, Regan K, Farina M, Schneider-Moran T, Zarudsky J. Long-term monitoring of mercury in adult saltmarsh sparrows breeding in Maine, Massachusetts and New York, USA 2000-2017. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1148-1160. [PMID: 32124146 DOI: 10.1007/s10646-020-02180-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/17/2020] [Indexed: 06/10/2023]
Abstract
Here we report on the results of a long-term study of mercury exposure in a songbird species, the saltmarsh sparrow (Ammodramus caudacutus). We measured total mercury concentrations in blood (n = 840) and feathers (n = 560) of adult saltmarsh sparrows at six locations between 2000 and 2017: Rachel Carson National Wildlife Refuge (RCNWR) in Wells, Maine; Scarborough Marsh State Wildlife Management Area in Scarborough, Maine; Parker River National Wildlife Refuge on Plum Island, Massachusetts; Pine Neck Preserve in Southampton, Long Island, New York; and North Cinder and North Green Sedge Islands off the coast of Long Island, New York. During the 12-17 year sampling periods, we found that mercury exposure differed by site and year but there was no consistent temporal trend across sites. Blood mercury concentrations declined only at RCNWR in Maine. We also found seasonal variation in blood mercury concentrations and a positive relationship between mercury concentrations of blood and innermost primary feather, but not between blood and tail feather.
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Affiliation(s)
- Oksana Lane
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA.
| | - Evan M Adams
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Nancy Pau
- USFWS, Parker River NWR, 6 Plum Island Turnpike, Newburyport, MA, 01950, USA
| | | | - Kevin Regan
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Michael Farina
- Town of Hempstead: Department of Conservation and Waterways, 1401 Lido Blvd, Point Lookout, NY, 11561, USA
| | - Tara Schneider-Moran
- Town of Hempstead: Department of Conservation and Waterways, 1401 Lido Blvd, Point Lookout, NY, 11561, USA
| | - John Zarudsky
- Town of Hempstead: Department of Conservation and Waterways, 1401 Lido Blvd, Point Lookout, NY, 11561, USA
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Yung L, Bertheau C, Cazaux D, Regier N, Slaveykova VI, Chalot M. Insect Life Traits Are Key Factors in Mercury Accumulation and Transfer within the Terrestrial Food Web. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:11122-11132. [PMID: 31466451 DOI: 10.1021/acs.est.9b04102] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
As plants and associated insects are at the bottom of some terrestrial food webs, they are the primary contributors to mercury (Hg) fluxes in ecosystems. In addition to the trophic position of these organisms, factors related to their life traits have been hypothesized to influence their exposure to Hg. This study investigates the transfer of Hg in a soil-nettle-insect system and the insect-related factors affecting their Hg concentrations in a revegetated chlor-alkali landfill. Twenty-three insect species were identified and classified according to their life traits, their relationship with nettle, and their morphological characteristics. We observed low total mercury (THg) concentrations in nettles, with only 1% methylmercury (MeHg) being detected, while concentrations ranged from 5 to 3700 μg/kg dry wt. in insects with a MeHg percentage of up to 75%. The nettle-related insects were primarily exposed to Hg through the food web with significant biomagnification, particularly at the level of secondary predators. Within the nettle-unrelated group, the insect habitat was the most explanatory factor, with the highest enrichment being for the insects that spent part of their cycle in direct contact with Hg sources. Therefore, these insects require special attention because they are an essential vector of Hg transfer for terrestrial top predators.
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Affiliation(s)
- Loïc Yung
- UMR CNRS 6249 Chrono-environnement , Université Bourgogne Franche-Comté , F-25200 Montbéliard , France
| | - Coralie Bertheau
- UMR CNRS 6249 Chrono-environnement , Université Bourgogne Franche-Comté , F-25200 Montbéliard , France
| | | | - Nicole Regier
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, Faculty of Sciences , University of Geneva , 1211 Geneva , Switzerland
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, Faculty of Sciences , University of Geneva , 1211 Geneva , Switzerland
| | - Michel Chalot
- UMR CNRS 6249 Chrono-environnement , Université Bourgogne Franche-Comté , F-25200 Montbéliard , France
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Faccio SD, Buckman KL, Lloyd JD, Curtis AN, Taylor VF. Bioaccumulation of methylmercury in wood frogs and spotted salamanders in Vermont vernal pools. ECOTOXICOLOGY (LONDON, ENGLAND) 2019; 28:717-731. [PMID: 31243636 PMCID: PMC6732234 DOI: 10.1007/s10646-019-02068-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/12/2019] [Indexed: 06/09/2023]
Abstract
Mercury (Hg) has accumulated in forested landscapes in the Northeastern U.S., and hotspots with enhanced deposition have been identified throughout the region. Due to a variety of favorable landscape characteristics, including relatively high dissolved organic carbon (DOC), fluctuating water levels, and low pH and dissolved oxygen, vernal pools provide ideal conditions for the conversion of Hg to its more toxic and bioavailable form, methylmercury (MeHg). Yet little is known about the concentrations, speciation, and bioavailability of Hg in vernal pools, or its bioaccumulation in vernal pool fauna and potential export into terrestrial systems. We investigated the role of forest cover type on the bioaccumulation of MeHg in wood frog (Lithobates sylvatica) and spotted salamander (Ambystoma maculatum) eggs, larvae, and adults, and investigated relationships among MeHg and water chemistry (pH, DOC). Water samples from pools located in coniferous stands had greater concentrations of THg and MeHg compared to deciduous pool water, and showed significant positive correlation to DOC (r = 0.683, P < 0.001) and correlated negatively with pH (r = -0.613, P < 0.001). Methylmercury levels in amphibian embryos were similar between the two species (L. sylvatica mean = 5.4 ng/g dw; A. maculatum mean = 3.5 ng/g dw). Concentrations of MeHg increased substantially in larvae, and were significantly greater in A. maculatum (mean = 237.6 ng/g ± 18.5 SE) than L. sylvatica larvae (62.5 ng/g ± 5.7 SE). Forest cover type did not explain variation in MeHg concentration among amphibian embryos or larvae. Methylmercury levels in adult tissue samples were significantly greater in A. maculatum (mean = 79.9 ng/g ± 8.9 SE) compared to L. sylvatica (mean = 47.7 ng/g ± 9.7 SE). This research demonstrates that vernal pools are important hotspots where amphibians bioaccumulate MeHg, which may then be transferred to terrestrial ecosystems. The abundance of amphibian larvae suggests they could be important bioindicators for monitoring MeHg loading and bioavailability.
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Affiliation(s)
| | - Kate L Buckman
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | | | - Amanda N Curtis
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
- Program in Ecology, Evolution and Conservation Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Vivien F Taylor
- Department of Earth Science, Dartmouth College, Hanover, NH, USA
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Xu Z, Abeysinghe KS, Xu X, Gu C, Liang L, Lu Q, Zhang Y, Zheng L, Wang WX, Qiu G. New insights into the chemical forms of extremely high methylmercury in songbird feathers from a contaminated site. CHEMOSPHERE 2019; 225:803-809. [PMID: 30904760 DOI: 10.1016/j.chemosphere.2019.03.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/21/2019] [Accepted: 03/10/2019] [Indexed: 06/09/2023]
Abstract
The chemical forms of mercury (Hg), particularly methylmercury (MeHg), in songbird feathers from an abandoned mining region were analyzed via X-ray absorption near-edge structure analysis (XANES). In feathers, proportions of MeHg as total mercury (75.6-100%) quantified by the XANES were directly comparable to the chemical extraction values (74.1-95.9%). Most of MeHg were bound with cysteine (Cys) and reduced glutathione (GSH), whereas inorganic mercury (IHg) was mainly bound with GSH. These results were consistent with those found in fish muscles and human hairs of both fish consumers and occupational Hg exposure populations. Our study suggested that chemical forms and speciation of Hg were highly dependent on the exposure sources and food consumption, respectively. Bird feathers were able to selectively accumulate MeHg due to their special binding ways. However, detailed mechanisms of Hg accumulation in bird feathers remain to be further elucidated.
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Affiliation(s)
- Zhidong Xu
- State Key laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kasun S Abeysinghe
- State Key laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaohang Xu
- State Key laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chunhao Gu
- Department of Ecosystems Science and Management, University of Wyoming, 82071, United States
| | - Longchao Liang
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Qinhui Lu
- State Key laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yubo Zhang
- Department of Agricultural Sciences, Anshun College, Anshun, 561000, China
| | - Lirong Zheng
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Wen-Xiong Wang
- Department of Ocean Science, Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong
| | - Guangle Qiu
- State Key laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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Rodenhouse NL, Lowe WH, Gebauer RLE, McFarland KP, Bank MS. Mercury bioaccumulation in temperate forest food webs associated with headwater streams. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 665:1125-1134. [PMID: 30893744 DOI: 10.1016/j.scitotenv.2019.02.151] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 01/25/2019] [Accepted: 02/09/2019] [Indexed: 06/09/2023]
Abstract
The soils and food webs associated with mid to high elevation, forested, headwater streams in northeastern North America are potential hotspots for mercury (Hg) methylation and bioaccumulation, but are not well studied. Our goals were to quantify total Hg (THg) and methyl Hg (MeHg) concentrations in soils and terrestrial food webs associated with headwater streams of northern hardwood forests to identify predictors of small-scale spatial variation in Hg bioaccumulation. We sampled soil characteristics that promote Hg methylation including pH, sulfur and calcium content, and organic matter. To assess spatial variation, we sampled at high (~700 m asl) and mid elevations (~500 m asl), both adjacent to (<1 m) and away from (>75 m) three replicate headwater streams in each of two watersheds of the White Mountains region, New Hampshire, USA. Soils of these forested watersheds differed significantly in pH and the content of calcium, sulfur, organic matter and THg. Conditions for methylation were more favorable in the upland forest sites compared to streamside sites. Significant bioaccumulation of THg occurred in all measured components of the food web, including insects, spiders, salamanders, and birds. Trophic position, as determined by δ15N, was the best predictor of both THg and MeHg bioaccumulation across the sampled taxa and was also a better predictor than spatial location. However, the degree of bioaccumulation at which MeHg significantly affects animal behavior, reproduction or survival is unknown for most taxa in terrestrial habitats, particularly for invertebrates. These findings show that Hg methylation and bioaccumulation is not limited to areas traditionally classified as wetlands or to areas with exceptionally high THg inputs, but that it is a widespread and important phenomenon in the moist deciduous forests of eastern North America.
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Affiliation(s)
| | - Winsor H Lowe
- Division of Biological Sciences, University of Montana, Missoula, MT, USA
| | | | | | - Michael S Bank
- Department of Environmental Conservation, University of Massachusetts, Amherst, MA, USA; Institute of Marine Research, Postboks 1870, Nordnes 5817, Bergen, Norway
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45
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Bourbour RP, Martinico BL, Ackerman JT, Herzog MP, Hull AC, Fish AM, Hull JM. Feather mercury concentrations in North American raptors sampled at migration monitoring stations. ECOTOXICOLOGY (LONDON, ENGLAND) 2019; 28:379-391. [PMID: 30761431 DOI: 10.1007/s10646-019-02016-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/05/2019] [Indexed: 06/09/2023]
Abstract
We assessed total mercury (THg) concentrations in breast feathers of diurnal North American raptors collected at migration monitoring stations. For 9 species in the Pacific Flyway, we found species and age influenced feather THg concentrations whereas sex did not. Feather THg concentrations µg/g dry weight (dw) averaged (least squares mean ± standard error) higher for raptors that generally consume > 75% avian prey (sharp-shinned hawk Accipiter striatus: n = 113; 4.35 ± 0.45 µg/g dw, peregrine falcon Falco peregrinus: n = 12; 3.93 ± 1.11 µg/g dw, Cooper's hawk Accipiter cooperii: n = 20; 2.35 ± 0.50 µg/g dw, and merlin Falco columbarius: n = 59; 1.75 ± 0.28 µg/g dw) than for raptors that generally consume < 75% avian prey (northern harrier Circus hudsonius: n = 112; 0.75 ± 0.10 µg/g dw, red-tailed hawk Buteo jamaicensis: n = 109; 0.56 ± 0.06 µg/g dw, American kestrel Falco sparverius: n = 16; 0.57 ± 0.14 µg/g dw, prairie falcon Falco mexicanus: n = 10; 0.41 ± 0.13 µg/g dw) except for red-shouldered hawks Buteo lineatus: n = 10; 1.94 ± 0.61 µg/g dw. Feather THg concentrations spanning 13-years (2002-2014) in the Pacific Flyway differed among 3 species, where THg increased for juvenile northern harrier, decreased for adult red-tailed hawk, and showed no trend for adult sharp-shinned hawk. Mean feather THg concentrations in juvenile merlin were greater in the Mississippi Flyway (n = 56; 2.14 ± 0.18 µg/g dw) than those in the Pacific Flyway (n = 49; 1.15 ± 0.11 µg/g dw) and Intermountain Flyway (n = 23; 1.14 ± 0.16 µg/g dw), and Atlantic Flyway (n = 38; 1.75 ± 0.19 µg/g dw) averaged greater than the Pacific Flyway. Our results indicate that raptor migration monitoring stations provide a cost-effective sampling opportunity for biomonitoring environmental contaminants within and between distinct migration corridors and across time.
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Affiliation(s)
- Ryan P Bourbour
- Department of Animal Science, University of California, Davis, Davis, CA, USA.
| | - Breanna L Martinico
- Department of Animal Science, University of California, Davis, Davis, CA, USA
| | - Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon, CA, USA
| | - Mark P Herzog
- U.S. Geological Survey, Western Ecological Research Center, Dixon, CA, USA
| | - Angus C Hull
- Golden Gate Raptor Observatory, Sausalito, CA, USA
| | - Allen M Fish
- Golden Gate Raptor Observatory, Sausalito, CA, USA
| | - Joshua M Hull
- Department of Animal Science, University of California, Davis, Davis, CA, USA
- Golden Gate Raptor Observatory, Sausalito, CA, USA
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46
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Tsz-Ki Tsui M, Liu S, Brasso RL, Blum JD, Kwon SY, Ulus Y, Nollet YH, Balogh SJ, Eggert SL, Finlay JC. Controls of Methylmercury Bioaccumulation in Forest Floor Food Webs. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:2434-2440. [PMID: 30727732 DOI: 10.1021/acs.est.8b06053] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Compared to the extensive research on aquatic ecosystems, very little is known about the sources and trophic transfer of methylmercury (MeHg) in terrestrial ecosystems. In this study, we examine energy flow and trophic structure using stable carbon (δ13C) and nitrogen (δ15N) isotope ratios, respectively, and MeHg levels in basal resources and terrestrial invertebrates from four temperate forest ecosystems. We show that MeHg levels in biota increased significantly ( p < 0.01) with δ13C and δ15N at all sites, implying the importance of both microbially processed diets (with increased δ13C) and trophic level (with increased δ15N) at which organisms feed, on MeHg levels in forest floor biota. The trophic magnification slopes of MeHg (defined as the slope of log10MeHg vs δ15N) for these forest floor food webs (0.20-0.28) were not significantly different ( p > 0.05) from those observed for diverse temperate freshwater systems (0.24 ± 0.07; n = 78), demonstrating for the first time the nearly equivalent efficiencies with which MeHg moves up the food chain in these contrasting ecosystem types. Our results suggest that in situ production of MeHg within the forest floor and efficient biomagnification both elevate MeHg levels in carnivorous invertebrates in temperate forests, which can contribute to significant bioaccumulation of this neurotoxin in terrestrial apex predators.
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Affiliation(s)
- Martin Tsz-Ki Tsui
- Department of Biology , University of North Carolina at Greensboro , Greensboro , North Carolina 27402 , United States
| | - Songnian Liu
- Department of Biology , University of North Carolina at Greensboro , Greensboro , North Carolina 27402 , United States
| | - Rebecka L Brasso
- Department of Zoology , Weber State University , Ogden , Utah 84408 , United States
| | - Joel D Blum
- Department of Earth and Environmental Sciences , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Sae Yun Kwon
- Division of Environmental Science and Engineering , Pohang University of Science and Technology , Pohang 37673 , South Korea
| | - Yener Ulus
- Department of Biology , University of North Carolina at Greensboro , Greensboro , North Carolina 27402 , United States
| | - Yabing H Nollet
- Metropolitan Council Environmental Services , St. Paul , Minnesota 55106 , United States
| | - Steven J Balogh
- Metropolitan Council Environmental Services , St. Paul , Minnesota 55106 , United States
| | - Sue L Eggert
- U.S.D.A. Forest Service , Northern Research Station, Grand Rapids , Minnesota 55744 , United States
| | - Jacques C Finlay
- Department of Ecology, Evolution, and Behavior , University of Minnesota , St. Paul , Minnesota 55108 , United States
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47
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Gerson AR, Cristol DA, Seewagen CL. Environmentally relevant methylmercury exposure reduces the metabolic scope of a model songbird. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 246:790-796. [PMID: 30623835 DOI: 10.1016/j.envpol.2018.12.072] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/21/2018] [Accepted: 12/22/2018] [Indexed: 06/09/2023]
Abstract
For most birds, energy efficiency and conservation are paramount to balancing the competing demands of self-maintenance, reproduction, and other demanding life history stages. Yet the ability to maximize energy output for behaviors like predator escape and migration is often also critical. Environmental perturbations that affect energy metabolism may therefore have important consequences for fitness and survival. Methylmercury (MeHg) is a global pollutant that has wide-ranging impacts on physiological systems, but its effects on the metabolism of birds and other vertebrates are poorly understood. We investigated dose-dependent effects of dietary MeHg on the body composition, basal and peak metabolic rates (BMR, PMR), and respiratory quotients (RQ) of zebra finches (Taeniopygia guttata). Dietary exposure levels (0.0, 0.1, or 0.6 ppm wet weight) were intended to reflect a range of mercury concentrations found in invertebrate prey of songbirds in areas contaminated by atmospheric deposition or point-source pollution. We found adiposity increased with MeHg exposure. BMR also increased with exposure while PMR decreased, together resulting in reduced metabolic scope in both MeHg-exposed treatments. There were differences in RQ among treatments that suggested a compromised ability of exposed birds to rapidly metabolize carbohydrates during exercise in a hop-hover wheel. The elevated BMR of exposed birds may have been due to energetic costs of depurating MeHg, whereas the reduced PMR could have been due to reduced oxygen carrying capacity and/or reduced glycolytic capacity. Our results suggest that environmentally relevant mercury exposure is capable of compromising the ability of songbirds to both budget and rapidly exert energy.
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Affiliation(s)
- Alexander R Gerson
- Department of Biology, University of Massachusetts, Amherst, MA, 01003, USA.
| | - Daniel A Cristol
- Biology Department, College of William & Mary, Williamsburg, VA, 23187, USA
| | - Chad L Seewagen
- Great Hollow Nature Preserve & Ecological Research Center, New Fairfield, CT, 06812, USA; AKRF Inc., White Plains, NY, 10601, USA
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48
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Wolfe JD, Lane OP, Brigham RM, Hall BD. Mercury exposure to red-winged blackbirds (Agelaius phoeniceus) and dragonfly (Odonata: Aeshnidae) nymphs in Prairie Pothole wetlands. Facets (Ott) 2018. [DOI: 10.1139/facets-2017-0086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Prairie Pothole Region (PPR) in the northern Great Plains is an area of ecological significance, serving as an important breeding site for avian wildlife. However, organisms feeding within the PPR may be at risk of mercury (Hg) exposure due to deposition of anthropogenic emissions and the high Hg methylation potential of PPR wetlands. We quantified Hg concentrations in red-winged blackbirds’ ( Agelaius phoeniceus (Linnaeus, 1766); RWBLs) blood, feathers, and eggs in the spring and summer breeding season and compared our values with those from RWBLs sampled from ecoregions across North America. Hg concentrations in whole water, aeshnid dragonfly nymphs, and RWBL tissues varied by wetland and were below those considered to elicit acute effects in wildlife, and egg total Hg (THg) concentrations were significantly related to spring whole water methylmercury concentrations. Only RWBL blood THg concentrations showed a clear increase in summer compared with spring, resulting in decoupling of summer blood and feather THg concentrations. Moreover, blood THg concentrations varied by ecoregion, with those impacted by an industrial point source exhibiting high Hg levels. Our study emphasizes that tissue renewal time as well as ecological factors such as competition and diet shifts are important considerations when using RWBLs to assess biological Hg exposure.
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Affiliation(s)
- Jared D. Wolfe
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
| | - Oksana P. Lane
- Biodiversity Research Institute, 276 Canco Road, Portland, ME 04103, USA
| | - R. Mark Brigham
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
| | - Britt D. Hall
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
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Fernandez-Cassi X, Supeanu A, Jansson A, Boqvist S, Vagsholm I. Novel foods: a risk profile for the house cricket ( Acheta domesticus). EFSA J 2018; 16:e16082. [PMID: 32626053 PMCID: PMC7015497 DOI: 10.2903/j.efsa.2018.e16082] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Novel foods could represent a sustainable alternative to traditional farming and conventional foodstuffs. Starting in 2018, Regulation (EU) 2283/2015 entered into force, laying down provisions for the approval of novel foods in Europe, including insects. This Approved Regulation establishes the requirements that enable Food Business Operators to bring new foods into the EU market, while ensuring high levels of food safety for European consumers. The present risk profile tackles the hazards for one of the most promising novel food insects, the house cricket (Acheta domesticus). The risk profile envisages a closed A. domesticus crickets rearing system, under Hazard Analysis and Critical Control Points (HACCP) and good farming practices (GFP), in contrast with open cricket farms. The methodology used involves screening the literature and identifying possible hazards, followed by adding relevant inclusion criteria for the evidence obtained. These criteria include animal health and food safety aspects, for the entire lifespan of crickets, based on the farm to fork One Health principle. When data were scarce, comparative evidence from close relatives of the Orthoptera genus was used (e.g. grasshoppers, locusts and other cricket species). Nevertheless, significant data gaps in animal health and food safety are present. Even if HACCP‐type systems are implemented, the risk profile identifies the following considerable concerns: (1) high total aerobic bacterial counts; (2) survival of spore‐forming bacteria following thermal processing; (3) allergenicity of insects and insect‐derived products; and (4) the bioaccumulation of heavy metals (e.g. cadmium). Other hazards like parasites, fungi, viruses, prions, antimicrobial resistance and toxins are ranked as low risk. For some hazards, a need for additional evidence is highlighted.
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50
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Yang Y, Yanai RD, Driscoll CT, Montesdeoca M, Smith KT. Concentrations and content of mercury in bark, wood, and leaves in hardwoods and conifers in four forested sites in the northeastern USA. PLoS One 2018; 13:e0196293. [PMID: 29684081 PMCID: PMC5912732 DOI: 10.1371/journal.pone.0196293] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 04/10/2018] [Indexed: 11/19/2022] Open
Abstract
Mercury (Hg) is deposited from the atmosphere to remote areas such as forests, but the amount of Hg in trees is not well known. To determine the importance of Hg in trees, we analyzed foliage, bark and bole wood of eight tree species at four sites in the northeastern USA (Huntington Forest, NY; Sleepers River, VT; Hubbard Brook, NH; Bear Brook, ME). Foliar concentrations of Hg averaged 16.3 ng g-1 among the hardwood species, which was significantly lower than values in conifers, which averaged 28.6 ng g-1 (p < 0.001). Similarly, bark concentrations of Hg were lower (p < 0.001) in hardwoods (7.7 ng g-1) than conifers (22.5 ng g-1). For wood, concentrations of Hg were higher in yellow birch (2.1-2.8 ng g-1) and white pine (2.3 ng g-1) than in the other species, which averaged 1.4 ng g-1 (p < 0.0001). Sites differed significantly in Hg concentrations of foliage and bark (p = 0.02), which are directly exposed to the atmosphere, but the concentration of Hg in wood depended more on species (p < 0.001) than site (p = 0.60). The Hg contents of tree tissues in hardwood stands, estimated from modeled biomass and measured concentrations at each site, were higher in bark (mean of 0.10 g ha-1) and wood (0.16 g ha-1) than in foliage (0.06 g ha-1). In conifer stands, because foliar concentrations were higher, the foliar pool tended to be more important. Quantifying Hg in tree tissues is essential to understanding the pools and fluxes of Hg in forest ecosystems.
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Affiliation(s)
- Yang Yang
- Department of Forest and Natural Resources Management, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States of America
| | - Ruth D. Yanai
- Department of Forest and Natural Resources Management, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States of America
| | - Charles T. Driscoll
- Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, United States of America
| | - Mario Montesdeoca
- Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, United States of America
| | - Kevin T. Smith
- USDA Forest Service, Northern Research Station, Durham, NH, United States of America
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