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Marlatt VL, Bayen S, Castaneda-Cortès D, Delbès G, Grigorova P, Langlois VS, Martyniuk CJ, Metcalfe CD, Parent L, Rwigemera A, Thomson P, Van Der Kraak G. Impacts of endocrine disrupting chemicals on reproduction in wildlife and humans. ENVIRONMENTAL RESEARCH 2022; 208:112584. [PMID: 34951986 DOI: 10.1016/j.envres.2021.112584] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
Endocrine disrupting chemicals (EDCs) are ubiquitous in aquatic and terrestrial environments. The main objective of this review was to summarize the current knowledge of the impacts of EDCs on reproductive success in wildlife and humans. The examples selected often include a retrospective assessment of the knowledge of reproductive impacts over time to discern how the effects of EDCs have changed over the last several decades. Collectively, the evidence summarized here within reinforce the concept that reproduction in wildlife and humans is negatively impacted by anthropogenic chemicals, with several altering endocrine system function. These observations of chemicals interfering with different aspects of the reproductive endocrine axis are particularly pronounced for aquatic species and are often corroborated by laboratory-based experiments (i.e. fish, amphibians, birds). Noteworthy, many of these same indicators are also observed in epidemiological studies in mammalian wildlife and humans. Given the vast array of reproductive strategies used by animals, it is perhaps not surprising that no single disrupted target is predictive of reproductive effects. Nevertheless, there are some general features of the endocrine control of reproduction, and in particular, the critical role that steroid hormones play in these processes that confer a high degree of susceptibility to environmental chemicals. New research is needed on the implications of chemical exposures during development and the potential for long-term reproductive effects. Future emphasis on field-based observations that can form the basis of more deliberate, extensive, and long-term population level studies to monitor contaminant effects, including adverse effects on the endocrine system, are key to addressing these knowledge gaps.
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Affiliation(s)
- V L Marlatt
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.
| | - S Bayen
- Department of Food Science and Agricultural Chemistry, McGill University, Montreal, QC, Canada
| | - D Castaneda-Cortès
- Centre Eau Terre Environnement, Institut National de la Recherche Scientifique (INRS), Laval, QC, Canada
| | - G Delbès
- Centre Armand Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, QC, Canada
| | - P Grigorova
- Département Science et Technologie, Université TELUQ, Montréal, QC, Canada
| | - V S Langlois
- Centre Eau Terre Environnement, Institut National de la Recherche Scientifique (INRS), Laval, QC, Canada
| | - C J Martyniuk
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, University of Florida, Gainesville, FL, United States
| | - C D Metcalfe
- School of Environment, Trent University, Trent, Canada
| | - L Parent
- Département Science et Technologie, Université TELUQ, Montréal, QC, Canada
| | - A Rwigemera
- Centre Armand Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, QC, Canada
| | - P Thomson
- Centre Eau Terre Environnement, Institut National de la Recherche Scientifique (INRS), Laval, QC, Canada
| | - G Van Der Kraak
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
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2
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Barraza AD, Finlayson KA, Leusch FDL, van de Merwe JP. Systematic review of reptile reproductive toxicology to inform future research directions on endangered or threatened species, such as sea turtles. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 286:117470. [PMID: 34438481 DOI: 10.1016/j.envpol.2021.117470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 04/28/2021] [Accepted: 05/24/2021] [Indexed: 06/13/2023]
Abstract
Threatened or endangered reptiles, such as sea turtles, are generally understudied within the field of wildlife toxicology, with even fewer studies on how contaminants affect threatened species reproduction. This paper aimed to better inform threatened species conservation by systematically and quantitatively reviewing available research on the reproductive toxicology of all reptiles, threatened and non-threatened. This review found 178 studies that matched our search criteria. These papers were categorized into location conducted, taxa studied, species studied, effects found, and chemicals investigated. The most studied taxa were turtles (n = 87 studies, 49%), alligators/crocodiles (n = 54, 30%), and lizards (n = 37, 21%). Maternal transfer, sex steroid alterations, sex reversal, altered sexual development, developmental abnormalities, and egg contamination were the most common effects found across all reptile taxa, providing guidance for avenues of research into threatened species. Maternal transfer of contaminants was found across all taxa, and taking into account the foraging behavior of sea turtles, could help elucidate differences in maternal transfer seen at nesting beaches. Sex steroid alterations were a common effect found with contaminant exposure, indicating the potential to use sex steroids as biomarkers along with traditional biomarkers such as vitellogenin. Sex reversal through chemical exposure was commonly found among species that exhibit temperature dependent sex determination, indicating the potential for both environmental pollution and climate change to disrupt population dynamics of many reptile species, including sea turtles. Few studies used in vitro, DNA, or molecular methodologies, indicating the need for more research using high-throughput, non-invasive, and cost-effective tools for threatened species research. The prevalence of developmental abnormalities and altered sexual development and function indicates the need to further study how anthropogenic pollutants affect reproductive output in threatened reptiles.
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Affiliation(s)
- Arthur D Barraza
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, 4222, Qld, Australia.
| | - Kimberly A Finlayson
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, 4222, Qld, Australia
| | - Frederic D L Leusch
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, 4222, Qld, Australia
| | - Jason P van de Merwe
- Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, 4222, Qld, Australia
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3
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Tavalieri YE, Galoppo GH, Canesini G, Luque EH, Muñoz-de-Toro MM. Effects of agricultural pesticides on the reproductive system of aquatic wildlife species, with crocodilians as sentinel species. Mol Cell Endocrinol 2020; 518:110918. [PMID: 32619582 DOI: 10.1016/j.mce.2020.110918] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 06/12/2020] [Accepted: 06/16/2020] [Indexed: 11/15/2022]
Abstract
Agricultural pesticides represent a significant class of endocrine-disrupting chemicals (EDCs) to which non-target organisms around the world are constantly exposed. Laboratory studies have found strong evidence showing the endocrine-disruptive potential of these pesticides at environmentally relevant exposure levels. Since the field of endocrine disruption continues to grow in richness and complexity, this review aims to provide an update on the effects of two agricultural pesticides that act as EDCs: atrazine and endosulfan. We will focus mainly on the effects on crocodilians due to their worldwide occurrence in tropical and sub-tropical wetland ecosystems and their ecological and physiological features, which render them vulnerable to exposure to pesticides with endocrine-disrupting action at all life stages. The results here reviewed provide important insights into the effects of hormonally active agricultural pesticides at cellular, tissue, and organ levels in the reproductive system of crocodiles. A better understanding of the effects of exposure to environmentally relevant doses of EDCs on the reproductive system of crocodilians will contribute to protect and improve the health of both wildlife species and humans.
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Affiliation(s)
- Y E Tavalieri
- Laboratorio de EcoFisioPatología, Instituto de Salud y Ambiente del Litoral (ISAL, UNL-CONICET), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - G H Galoppo
- Laboratorio de EcoFisioPatología, Instituto de Salud y Ambiente del Litoral (ISAL, UNL-CONICET), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - G Canesini
- Laboratorio de EcoFisioPatología, Instituto de Salud y Ambiente del Litoral (ISAL, UNL-CONICET), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - E H Luque
- Laboratorio de EcoFisioPatología, Instituto de Salud y Ambiente del Litoral (ISAL, UNL-CONICET), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - M M Muñoz-de-Toro
- Laboratorio de EcoFisioPatología, Instituto de Salud y Ambiente del Litoral (ISAL, UNL-CONICET), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina.
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4
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Hirano LQL, Alves LDS, Menezes-Reis LT, Mendonça JDS, Simões K, Santos ALQ, Vieira LG. Effects of egg exposure to atrazine and/or glyphosate on bone development in Podocnemis unifilis (Testudines, Podocnemididae). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 182:109400. [PMID: 31276883 DOI: 10.1016/j.ecoenv.2019.109400] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
This study was designed to investigate skeletal changes in Podocnemis unifilis embryos derived from artificially incubated eggs exposed to different concentrations of atrazine, glyphosate or atrazine and glyphosate mixture. Forty-two eggs were randomly allocated to one of seven trays containing vermiculite treated distilled water (control group) or the following solutions: 2 or 200 μg L-1 of atrazine (groups A1 and A2 respectively); 65 or 6500 μg L-1 of glyphosate (groups G1 and G2 respectively); 2 μg L-1 and 65 μg L-1 or 200 μg L-1 and 6500 μg L-1 of atrazine and glyphosate mixture (groups AG1 and AG2 respectively). Three eggs per tray were randomly collected on days 30 and 50 of the incubation period. Embryos were submitted to soft tissue diaphanization and stained with Alizarin red S or Alcian blue for morphological analysis of bone and cartilage tissues; histological analysis was performed to confirm ossification changes. Findings were compared between groups. Morphological changes were limited to sclerotic ring features and number of ribs. Malformations rates differed significantly (p < 0.05) between embryos in the control and treated groups A2, AG1 and AG2. Concurrent exposure to atrazine and glyphosate did not affect the presence or severity of embryonic malformations and was not associated with appendicular skeleton changes in P. unifilis embryos. However, further studies focusing on the axial skeleton with particular emphasis on rib abnormalities are warranted.
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Affiliation(s)
| | | | | | | | - Karina Simões
- (b)Federal University of Goiás (UFG), Goiânia, Goiás, Brazil
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Carneiro IV, Gonçalves Vieira L, Dos Santos Mendonça J, Queiroz Luz Hirano L, Chavauty Valdes SA, Tannús Menezes-Reis L, Quagliatto Santos AL. Development of scleral ossicles in Podocnemis expansa (Testudines: Podocnemididae) embryos exposed to atrazine. Drug Chem Toxicol 2019; 44:353-358. [PMID: 31195844 DOI: 10.1080/01480545.2019.1598427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Understanding the effects of atrazine exposure on embryo development in oviparous animals may provide important data regarding the impacts of agrochemical use on wildlife and the ecosystem. This study set out to determine the effects of embryonic atrazine exposure on the development of osseous and cartilaginous components of scleral ossicles in Podocnemis expansa. Eggs were collected at the Environmental Protection Area Meandros do Rio Araguaia, Brazil, and artificially incubated in sand treated with solutions containing 2, 20 or 200 µg/L of atrazine. Sixty embryos were collected per treatment throughout the incubation period. Embryos were diaphanized with potassium hydroxide (KOH) and stained with Alizarin Red S and Alcian blue (bone and cartilage tissue respectively). Scleral ossicles were then counted and examined for skeletal abnormalities at different stages of embryonic development. Scleral ossicle counts were significantly reduced in P. expansa embryos treated with 200 μg/L atrazine solution. Rudimentary ossicles and gaps were also noted in embryos exposed to atrazine concentrations of 2 μg/L or 200 μg/L. Findings of this study emphasize the relevance of ecotoxicological investigations in determining the impacts of agrochemicals on native fauna.
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Affiliation(s)
- Isabela Vieira Carneiro
- Laboratory of Wildlife Education and Research, Federal University of Uberlândia (UFU), Uberlândia, Minas Gerais, Brazil
| | | | | | - Líria Queiroz Luz Hirano
- Postgraduate Program in Animal Health, Federal University of Brasília (UnB), Brasília, Distrito Federal, Brazil
| | | | - Lorena Tannús Menezes-Reis
- Institute of Biological Sciences, Federal University of Uberlândia (UFU), Uberlândia, Minas Gerais, Brazil
| | - André Luiz Quagliatto Santos
- Laboratory of Wildlife Education and Research, Federal University of Uberlândia (UFU), Uberlândia, Minas Gerais, Brazil
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Saalfeld GQ, Varela Junior AS, Castro T, Pereira FA, Gheller SMM, da Silva AC, Corcini CD, da Rosa CE, Colares EP. Low atrazine dosages reduce sperm quality of Calomys laucha mice. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:2924-2931. [PMID: 29147981 DOI: 10.1007/s11356-017-0657-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 10/31/2017] [Indexed: 06/07/2023]
Abstract
Reproductive effects caused by the exposure to environmentally relevant dosages of atrazine on wild animals are poorly understood. This study evaluated the effects of three dosages of atrazine on sperm parameters of adult Calomys laucha males. Adult mice were orally exposed to dosages of 0 (water and vehicle control), 0.1, 1, and 10 mg/kg of animal weight for a 21-day period. Following exposure, analyses were performed to determine sperm motility parameters, plasma membrane integrity and fluidity, mitochondrial functionality, acrosome integrity, DNA damage, lipid peroxidation, and production of reactive oxygen species (ROS) in the sperm samples. Total and progressive motility were reduced in all dosages in comparison to control groups. Membrane integrity and mitochondrial functionality of sperm were reduced in all dosages, and the sperm membrane fluidity increased in the higher dosages of atrazine (1 and 10 mg/kg), in comparison with the vehicle control. A decrease in the acrosome integrity was noted at 10 mg/kg of atrazine, compared to the control groups. The integrity of DNA, ROS generation, and lipid peroxidation of sperm showed no significant differences when compared with the control groups. These results suggest that exposure to low dosages of atrazine can affect sperm parameters of Calomys laucha and therefore reduce the reproductive capacity of wild rodent species.
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Affiliation(s)
- Graciela Quintana Saalfeld
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Avenida Itália, km 08 s/n, Caixa Postal 474, Rio Grande, RS, 96201-900, Brazil.
| | - Antônio Sergio Varela Junior
- Reprodução Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil
| | - Tiane Castro
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Avenida Itália, km 08 s/n, Caixa Postal 474, Rio Grande, RS, 96201-900, Brazil
| | - Fernanda Alves Pereira
- Reprodução Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil
| | - Stela Mari Meneghello Gheller
- Reprodução Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil
- ReproPel, Faculdade de Veterinária, Campus Capão do Leão, Universidade Federal de Pelotas (UFPel), Pelotas, RS, Brazil
| | - Alessandra Cardoso da Silva
- ReproPel, Faculdade de Veterinária, Campus Capão do Leão, Universidade Federal de Pelotas (UFPel), Pelotas, RS, Brazil
| | - Carine Dahl Corcini
- Reprodução Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil
- ReproPel, Faculdade de Veterinária, Campus Capão do Leão, Universidade Federal de Pelotas (UFPel), Pelotas, RS, Brazil
| | - Carlos Eduardo da Rosa
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Avenida Itália, km 08 s/n, Caixa Postal 474, Rio Grande, RS, 96201-900, Brazil
| | - Elton Pinto Colares
- Reprodução Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil
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7
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Allan HL, van de Merwe JP, Finlayson KA, O'Brien JW, Mueller JF, Leusch FDL. Analysis of sugarcane herbicides in marine turtle nesting areas and assessment of risk using in vitro toxicity assays. CHEMOSPHERE 2017; 185:656-664. [PMID: 28728123 DOI: 10.1016/j.chemosphere.2017.07.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 07/06/2017] [Accepted: 07/07/2017] [Indexed: 06/07/2023]
Abstract
Agricultural processes are associated with many different herbicides that can contaminate surrounding environments. In Queensland, Australia, herbicides applied to agricultural crops may pose a threat to valuable coastal habitats including nesting beaches for threatened loggerhead turtles (Caretta caretta). This study 1) measured concentrations of herbicides in the beach sand of Mon Repos, an important marine turtle nesting beach in Australia that is adjacent to significant sugarcane crops, and 2) investigated the toxicity of these herbicides to marine turtles using a cell-based assay. Samples of sand from turtle nest depth and water from surrounding agricultural drains and wetlands were collected during the wet season when herbicide runoff was expected to be the greatest and turtles were nesting. Samples were extracted using solid phase extraction and extracts were analysed using chemical analysis targeting herbicides, as well as bioanalytical techniques (IPAM-assay and loggerhead turtle skin cell cytotoxicity assay). Twenty herbicides were detected in areas between sugarcane crops and the nesting beach, seven of which were also detected in the sand extracts. Herbicides present in the nearby wetland were also detected in the beach sand, indicating potential contamination of the nesting beach via the river outlet as well as ground water. Although herbicides were detected in nesting sand, bioassays using loggerhead turtle skin cells indicated a low risk of acute toxicity at measured environmental concentrations. Further research should investigate potentially more subtle effects, such as endocrine disruption and mixture effects, to better assess the threat that herbicides pose to this population of marine turtles.
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Affiliation(s)
- Hannah L Allan
- Australian Rivers Institute & Griffith School of Environment, Griffith University, Parklands Drive, Gold Coast, QLD 4222, Australia
| | - Jason P van de Merwe
- Australian Rivers Institute & Griffith School of Environment, Griffith University, Parklands Drive, Gold Coast, QLD 4222, Australia.
| | - Kimberly A Finlayson
- Australian Rivers Institute & Griffith School of Environment, Griffith University, Parklands Drive, Gold Coast, QLD 4222, Australia
| | - Jake W O'Brien
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 39 Kessels Rd, Coopers Plains, QLD 4108, Australia
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 39 Kessels Rd, Coopers Plains, QLD 4108, Australia
| | - Frederic D L Leusch
- Australian Rivers Institute & Griffith School of Environment, Griffith University, Parklands Drive, Gold Coast, QLD 4222, Australia
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McGlashan JK, Thompson MB, Van Dyke JU, Spencer RJ. Thyroid Hormones Reduce Incubation Period without Developmental or Metabolic Costs in Murray River Short-Necked Turtles (Emydura macquarii). Physiol Biochem Zool 2017; 90:34-46. [DOI: 10.1086/689744] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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9
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Endocrine Disruption and In Vitro Ecotoxicology: Recent Advances and Approaches. IN VITRO ENVIRONMENTAL TOXICOLOGY - CONCEPTS, APPLICATION AND ASSESSMENT 2017; 157:1-58. [DOI: 10.1007/10_2016_2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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10
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Effect of atrazine on immunocompetence of red-eared slider turtle(Trachemys scripta). J Immunotoxicol 2016; 13:804-809. [DOI: 10.1080/1547691x.2016.1195463] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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11
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Russart KL, Rhen T. Atrazine alters expression of reproductive and stress genes in the developing hypothalamus of the snapping turtle, Chelydra serpentina. Toxicology 2016; 366-367:1-9. [DOI: 10.1016/j.tox.2016.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 07/27/2016] [Accepted: 08/01/2016] [Indexed: 11/16/2022]
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12
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Mendonça JDS, Vieira LG, Valdes SAC, Vilca FZ, Tornisielo VL, Santos ALQ. Effects of the exposure to atrazine on bone development of Podocnemis expansa (Testudines, Podocnemididae). ECOTOXICOLOGY (LONDON, ENGLAND) 2016; 25:594-600. [PMID: 26850621 DOI: 10.1007/s10646-016-1618-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/27/2016] [Indexed: 06/05/2023]
Abstract
The use of pesticides is a widely spread practice in Brazilian agriculture, and dispersion of these substances is an important factor for the fauna and flora. Atrazine is an endocrine disruptor in the xenoestrogen class that is used worldwide in agricultural practices. In Brazil, its use is permitted in several crops. Podocnemis expansa is a representative of the Testudines order that is the largest freshwater reptile of South America. Its distribution enables it to get in contact with molecules that are commonly used as pesticides, which may cause deleterious effects in target populations. In order to evaluate the possible effects of the exposure to atrazine on bone ontogeny of this species, eggs were artificially incubated in sand moistened with water contaminated with atrazine at concentrations equal to 0, 2, 20 or 200 μg/L. Embryos were collected throughout incubation and submitted to diaphanization of soft tissues with potassium hydroxide (KOH); bones were stained with Alizarin red S and cartilages by Alcian blue. Embryos were evaluated for the presence of abnormalities during the different stages of pre-natal development of skeletal elements. No effect of atrazine was observed on bone development during the embryonic phase in P. expansa individuals, in the conditions of this study.
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Affiliation(s)
- Juliana dos Santos Mendonça
- Wild Animal Research and Teaching Laboratory (LAPAS), Universidade Federal de Uberlândia (UFU), Rua Piaui, S/N, Campos Umuarama, Av. Jardim Umuarama, Uberlândia, MG, CEP 38400-902, Brazil.
| | - Lucélia Gonçalves Vieira
- Wild Animal Research and Teaching Laboratory (LAPAS), Universidade Federal de Uberlândia (UFU), Rua Piaui, S/N, Campos Umuarama, Av. Jardim Umuarama, Uberlândia, MG, CEP 38400-902, Brazil
| | - Sady Alexis Chavauty Valdes
- Wild Animal Research and Teaching Laboratory (LAPAS), Universidade Federal de Uberlândia (UFU), Rua Piaui, S/N, Campos Umuarama, Av. Jardim Umuarama, Uberlândia, MG, CEP 38400-902, Brazil
| | - Franz Zirena Vilca
- Ecotoxicology Laboratory, Centro de Energia Nuclear na Agricultura da Universidade de São Paulo (CENA/USP), Piracicaba, SP, Brazil
| | - Valdemar Luiz Tornisielo
- Ecotoxicology Laboratory, Centro de Energia Nuclear na Agricultura da Universidade de São Paulo (CENA/USP), Piracicaba, SP, Brazil
| | - André Luiz Quagliatto Santos
- Wild Animal Research and Teaching Laboratory (LAPAS), Universidade Federal de Uberlândia (UFU), Rua Piaui, S/N, Campos Umuarama, Av. Jardim Umuarama, Uberlândia, MG, CEP 38400-902, Brazil
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13
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Mizoguchi BA, Valenzuela N. Ecotoxicological Perspectives of Sex Determination. Sex Dev 2016; 10:45-57. [DOI: 10.1159/000444770] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2015] [Indexed: 11/19/2022] Open
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Van Der Kraak GJ, Hosmer AJ, Hanson ML, Kloas W, Solomon KR. Effects of atrazine in fish, amphibians, and reptiles: an analysis based on quantitative weight of evidence. Crit Rev Toxicol 2015; 44 Suppl 5:1-66. [PMID: 25375889 DOI: 10.3109/10408444.2014.967836] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A quantitative weight of evidence (WoE) approach was developed to evaluate studies used for regulatory purposes, as well as those in the open literature, that report the effects of the herbicide atrazine on fish, amphibians, and reptiles. The methodology for WoE analysis incorporated a detailed assessment of the relevance of the responses observed to apical endpoints directly related to survival, growth, development, and reproduction, as well as the strength and appropriateness of the experimental methods employed. Numerical scores were assigned for strength and relevance. The means of the scores for relevance and strength were then used to summarize and weigh the evidence for atrazine contributing to ecologically significant responses in the organisms of interest. The summary was presented graphically in a two-dimensional graph which showed the distributions of all the reports for a response. Over 1290 individual responses from studies in 31 species of fish, 32 amphibians, and 8 reptiles were evaluated. Overall, the WoE showed that atrazine might affect biomarker-type responses, such as expression of genes and/or associated proteins, concentrations of hormones, and biochemical processes (e.g. induction of detoxification responses), at concentrations sometimes found in the environment. However, these effects were not translated to adverse outcomes in terms of apical endpoints. The WoE approach provided a quantitative, transparent, reproducible, and robust framework that can be used to assist the decision-making process when assessing environmental chemicals. In addition, the process allowed easy identification of uncertainty and inconsistency in observations, and thus clearly identified areas where future investigations can be best directed.
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Douros DL, Gaines KF, Novak JM. Atrazine and glyphosate dynamics in a lotic ecosystem: the common snapping turtle as a sentinel species. ENVIRONMENTAL MONITORING AND ASSESSMENT 2015; 187:114. [PMID: 25678354 DOI: 10.1007/s10661-015-4336-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Accepted: 01/28/2015] [Indexed: 06/04/2023]
Abstract
Atrazine and glyphosate are two of the most common pesticides used in the US Midwest that impact water quality via runoff, and the common snapping turtle (Chelydra serpentina) is an excellent indicator species to monitor these pesticides especially in lotic systems. The goals of this study were to (1) quantify atrazine, the atrazine metabolite diaminochlorotriazine (DACT), and glyphosate burdens in common snapping turtle tissue from individuals collected within the Embarras River in Illinois; (2) quantify atrazine, DACT, and glyphosate loads in water from the aquatic habitats in which common snapping turtles reside; and (3) investigate tissue loads based on turtle morphology and habitat choice. Concentrations of atrazine, DACT, and glyphosate in tissue did not show any relationship with lake habitat, carapace length, width, or mass. Both atrazine and glyphosate tissue samples varied as a function of site (river vs. lake), but DACT did not. Atrazine and glyphosate concentrations in water samples showed a linear effect on distance from the reservoir spillway and a deviation from linearity. Water column concentrations of all three contaminants varied across capture sites, but atrazine water concentration did not influence DACT water concentration nor did it exhibit a site interaction. Water atrazine and glyphosate concentrations were greater than tissue concentrations, whereas DACT water and tissue concentrations did not differ. This study showed that turtles are useful in long-term pesticide monitoring, and because DACT as a metabolite is less sensitive to variation, it should be considered as a preferred biomarker for pesticide runoff.
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Affiliation(s)
- Derrick L Douros
- Department of Biological Sciences, Eastern Illinois University, Charleston, IL, 61920, USA
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Neuman-Lee LA, Gaines KF, Baumgartner KA, Voorhees JR, Novak JM, Mullin SJ. Assessing multiple endpoints of atrazine ingestion on gravid Northern Watersnakes (Nerodia sipedon) and their offspring. ENVIRONMENTAL TOXICOLOGY 2014; 29:1072-1082. [PMID: 23436772 DOI: 10.1002/tox.21837] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 12/07/2012] [Indexed: 06/01/2023]
Abstract
Ecotoxicological studies that focus on a single endpoint might not accurately and completely represent the true ecological effects of a contaminant. Exposure to atrazine, a widely used herbicide, disrupts endocrine function and sexual development in amphibians, but studies involving live-bearing reptiles are lacking. This study tracks several effects of atrazine ingestion from female Northern Watersnakes (Nerodia sipedon) to their offspring exposed in utero. Twenty-five gravid N. sipedon were fed fish dosed with one of the four levels of atrazine (0, 2, 20, or 200 ppb) twice weekly for the entirety of their gestation period. Endpoints for the mothers included blood estradiol levels measured weekly and survival more than 3 months. Endpoints for the offspring included morphometrics, clutch sex ratio, stillbirth, and asymmetry of dorsal scales and jaw length. Through these multiple endpoints, we show that atrazine ingestion can disrupt estradiol production in mothers, increase the likelihood of mortality from infection, alter clutch sex ratio, cause a higher proportion of stillborn offspring, and affect scale symmetry. We emphasize the need for additional research involving other reptile species using multiple endpoints to determine the full range of impacts of contaminant exposure.
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Affiliation(s)
- Lorin A Neuman-Lee
- Department of Biological Sciences, Eastern Illinois University, Charleston, Illinois 61920, USA
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Mayfield DB, Johnson MS, Burris JA, Fairbrother A. Furthering the derivation of predictive wildlife toxicity reference values for use in soil cleanup decisions. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2014; 10:358-371. [PMID: 23913912 DOI: 10.1002/ieam.1474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 05/07/2013] [Accepted: 07/17/2013] [Indexed: 06/02/2023]
Abstract
The development of media-specific ecological values for risk assessment includes the derivation of acceptable levels of exposure for terrestrial wildlife (e.g., birds, mammals, reptiles, and amphibians). Although the derivation and subsequent application of these values can be used for screening purposes, there is a need to identify toxicological effects thresholds specifically for making remedial decisions at individual contaminated sites. A workshop was held in the fall of 2012 to evaluate existing methods and recent scientific developments for refining ecological soil screening levels (Eco-SSLs) and improving the derivation of site-specific ecological soil clean-up values for metals (Eco-SCVs). This included a focused session on the development and derivation of toxicity reference values (TRVs) for terrestrial wildlife. Topics that were examined included: methods for toxicological endpoint selection, techniques for dose-response assessment, approaches for cross-species extrapolation, and tools to incorporate environmental factors (e.g., metal bioavailability and chemistry) into a reference value. The workgroup also made recommendations to risk assessors and regulators on how to incorporate site-specific wildlife life history and toxicity information into the derivation of TRVs to be used in the further development of soil cleanup levels.
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Walters AD, Chamberlain K, Ford NB, Placyk JS. Influence of atrazine on the scalation of Marcy's checkered gartersnake, Thamnophis m. marcianus (Baird and Girard, 1853). BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2014; 92:1-5. [PMID: 24178231 DOI: 10.1007/s00128-013-1147-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 10/24/2013] [Indexed: 06/02/2023]
Abstract
Atrazine is one of the most commonly used herbicides in the United States. Despite the effectiveness of atrazine in eliminating broadleaf and grassy weeds, there has been growing concern over the potential impacts this chemical may have on non-target organisms. Little research has been conducted on the exposure of reptiles to this chemical. Our study examined the effects of environmentally relevant concentrations of atrazine on the scalation of Marcy's checkered gartersnake (Thamnophis m. marcianus). Our results indicate that atrazine exposure influences scalation, in particular, cranial scale counts. In addition, this alteration of morphology happens during embryological development as the result of the environment the mother was raised in. Further research on additional species and developmental exposure of atrazine and how it influences fitness of reptiles is required.
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Affiliation(s)
- Ashley D Walters
- Department of Biology, University of Texas at Tyler, 3900 University Blvd, Tyler, TX, 75799, USA
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Amaral MJ, Carretero MA, Bicho RC, Soares AMVM, Mann RM. The use of a lacertid lizard as a model for reptile ecotoxicology studies--part 1 field demographics and morphology. CHEMOSPHERE 2012; 87:757-764. [PMID: 22321810 DOI: 10.1016/j.chemosphere.2011.12.075] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 12/25/2011] [Accepted: 12/30/2011] [Indexed: 05/27/2023]
Abstract
At the European level, lacertid lizards have been proposed as potential model species for reptile ecotoxicology. We studied demographic and morphological aspects of natural field subpopulations of Podarcis bocagei inhabiting similar agricultural habitats which were either regularly exposed to pesticides, or not. Parameters examined in this study included population size and density, sex ratio, adult body size, fluctuating asymmetry in femoral pores and parasite prevalence. In general, we detected few statistically significant differences between the exposed and reference subpopulations. Although field situations are ecologically complex and factors other than pesticides may be acting, the absence of observable effects on field subpopulations is probably indicative that lizards are coping or compensating for this level of exposure.
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Affiliation(s)
- Maria José Amaral
- CESAM & Departmento de Biologia, Universidade de Aveiro, 3810-193 Aveiro, Portugal.
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Hayes TB, Anderson LL, Beasley VR, de Solla SR, Iguchi T, Ingraham H, Kestemont P, Kniewald J, Kniewald Z, Langlois VS, Luque EH, McCoy KA, Muñoz-de-Toro M, Oka T, Oliveira CA, Orton F, Ruby S, Suzawa M, Tavera-Mendoza LE, Trudeau VL, Victor-Costa AB, Willingham E. Demasculinization and feminization of male gonads by atrazine: consistent effects across vertebrate classes. J Steroid Biochem Mol Biol 2011; 127:64-73. [PMID: 21419222 PMCID: PMC4303243 DOI: 10.1016/j.jsbmb.2011.03.015] [Citation(s) in RCA: 203] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 02/08/2011] [Accepted: 03/04/2011] [Indexed: 12/20/2022]
Abstract
Atrazine is the most commonly detected pesticide contaminant of ground water, surface water, and precipitation. Atrazine is also an endocrine disruptor that, among other effects, alters male reproductive tissues when animals are exposed during development. Here, we apply the nine so-called "Hill criteria" (Strength, Consistency, Specificity, Temporality, Biological Gradient, Plausibility, Coherence, Experiment, and Analogy) for establishing cause-effect relationships to examine the evidence for atrazine as an endocrine disruptor that demasculinizes and feminizes the gonads of male vertebrates. We present experimental evidence that the effects of atrazine on male development are consistent across all vertebrate classes examined and we present a state of the art summary of the mechanisms by which atrazine acts as an endocrine disruptor to produce these effects. Atrazine demasculinizes male gonads producing testicular lesions associated with reduced germ cell numbers in teleost fish, amphibians, reptiles, and mammals, and induces partial and/or complete feminization in fish, amphibians, and reptiles. These effects are strong (statistically significant), consistent across vertebrate classes, and specific. Reductions in androgen levels and the induction of estrogen synthesis - demonstrated in fish, amphibians, reptiles, and mammals - represent plausible and coherent mechanisms that explain these effects. Biological gradients are observed in several of the cited studies, although threshold doses and patterns vary among species. Given that the effects on the male gonads described in all of these experimental studies occurred only after atrazine exposure, temporality is also met here. Thus the case for atrazine as an endocrine disruptor that demasculinizes and feminizes male vertebrates meets all nine of the "Hill criteria".
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Affiliation(s)
- Tyrone B Hayes
- Laboratory for Integrative Studies in Amphibian Biology, Molecular Toxicology, Museum of Vertebrate Zoology, and Department of Integrative Biology, University of California, Berkeley, CA 94720, USA.
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Solla SRD, Martin PA. Absorption of current use pesticides by snapping turtle (Chelydra serpentina) eggs in treated soil. CHEMOSPHERE 2011; 85:820-825. [PMID: 21862099 DOI: 10.1016/j.chemosphere.2011.06.080] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 06/17/2011] [Accepted: 06/20/2011] [Indexed: 05/31/2023]
Abstract
Reptiles often breed within agricultural and urban environments that receive frequent pesticide use. Consequently, their eggs and thus developing embryos may be exposed to pesticides. Our objectives were to determine (i) if turtle eggs are capable of absorbing pesticides from treated soil, and (ii) if pesticide absorption rates can be predicted by their chemical and physical properties. Snapping turtle (Chelydra serpentina) eggs were incubated in soil that was treated with 10 pesticides (atrazine, simazine, metolachlor, azinphos-methyl, dimethoate, chlorpyrifos, carbaryl, endosulfan (I and II), captan, and chlorothalonil). There were two treatments, consisting of pesticides applied at application rate equivalents of 1.92 or 19.2 kg a.i/ha. Eggs were removed after one and eight days of exposure and analyzed for pesticides using gas chromatography coupled with a mass selective detector (GC-MSD) or high performance liquid chromatography (HPLC). Absorption of pesticides in eggs from soil increased with both magnitude and duration of exposure. Of the 10 pesticides, atrazine and metolachlor generally had the greatest absorption, while azinphos-methyl had the lowest. Chlorothalonil was below detection limits at both exposure rates. Our preliminary model suggests that pesticides having the highest absorption into eggs tended to have both low sorption to organic carbon or lipids, and high water solubility. For pesticides with high water solubility, high vapor pressure may also increase absorption. As our model is preliminary, confirmatory studies are needed to elucidate pesticide absorption in turtle eggs and the potential risk they may pose to embryonic development.
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Affiliation(s)
- Shane Raymond de Solla
- Wildlife and Landscape Science Directorate, Environment Canada, Canada Centre for Inland Waters, Burlington, Ontario, Canada.
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de Solla SR, Martin PA, Mikoda P. Toxicity of pesticide and fertilizer mixtures simulating corn production to eggs of snapping turtles (Chelydra serpentina). THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:4306-4311. [PMID: 21831407 DOI: 10.1016/j.scitotenv.2011.06.046] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 06/20/2011] [Accepted: 06/22/2011] [Indexed: 05/31/2023]
Abstract
Many reptiles oviposit in soils associated with agricultural landscapes. We evaluated the toxicity of a pesticide and fertilizer regime similar to those used in corn production in Ontario on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. The herbicides atrazine, dimethenamid, and glyphosate, the pyrethroid insecticide tefluthrin, and the fertilizer ammonia, were applied to clean soil, both as partial mixtures within chemical classes, as well as complete mixtures. Eggs were incubated in the soil in a garden plot in which these mixtures were applied at a typical field application rate, and higher rates. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed at male producing temperatures in the laboratory in covered bins in the same soil, where there was less opportunity for loss through volatilization or leaching. Egg mortality was 100% at 10× the typical field application rate of the complete mixture, both with and without tefluthrin. At typical field application rates, hatching success ranged between 91.7 and 95.8%. Eggs exposed only to herbicides were not negatively affected at any application rates. Although fertilizer treatments at typical field application rates did not affect eggs, mortality was remarkably higher at three times this rate, and 100% at higher rates. The frequency of deformities of hatchlings was elevated at the highest application rate of the insecticide tefluthrin. The majority of the toxicity of the mixture was not due to the herbicides or insecticide, but was due to the ammonia fertilizer. At typical field application rates, the chemical regime associated with corn production does not appear to have any detrimental impacts upon turtle egg development; however toxicity dramatically increases if this threshold is passed.
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Affiliation(s)
- Shane Raymond de Solla
- Wildlife and Landscape Science Directorate, Environment Canada, 867 Lakeshore Road, Burlington, Ontario, Canada.
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Storrs-Méndez SI, Semlitsch RD. Intersex gonads in frogs: understanding the time course of natural development and role of endocrine disruptors. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2010; 314:57-66. [DOI: 10.1002/jez.b.21310] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Solomon KR, Carr JA, Du Preez LH, Giesy JP, Kendall RJ, Smith EE, Van Der Kraak GJ. Effects of Atrazine on Fish, Amphibians, and Aquatic Reptiles: A Critical Review. Crit Rev Toxicol 2008; 38:721-72. [DOI: 10.1080/10408440802116496] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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de Solla SR, Fernie KJ, Ashpole S. Snapping turtles (Chelydra serpentina) as bioindicators in Canadian areas of concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2008; 153:529-536. [PMID: 18039552 DOI: 10.1016/j.envpol.2007.09.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 09/17/2007] [Accepted: 09/23/2007] [Indexed: 05/25/2023]
Abstract
Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities.
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Affiliation(s)
- S R de Solla
- Population Assessment Unit, Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, Canada L7R 4A6.
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Eldridge JC, Stevens JT, Breckenridge CB. Atrazine interaction with estrogen expression systems. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2008; 196:147-160. [PMID: 19025096 DOI: 10.1007/978-0-387-78444-1_6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
More than 40 publications have described results of atrazine responses in 17 estrogen-dependent systems and in more than a dozen different reporter and estrogen receptor-binding studies in vitro. Results from these studies have consistently failed to demonstrate that atrazine acts as an estrogen agonist. Moreover, a variety of indices of estrogen-dependent activity, in models that encompass cell incubations to whole animals, have failed to respond to atrazine. Researchers in more than a dozen laboratories have examined rats, rat tissues, human and prokaryotic cells, in addition to tissues from reptile, fish, amphibian, avian, molluscan, and insect sources, without eliciting estrogenic-like responses from atrazine. In contrast, studies of atrazine ability to antagonize estrogen-mediated responses have yielded equivocal results. Results of several studies show inhibition of estrogen-like activities by atrazine, yet many other tests have yielded negative results. Generally, in vivo models have more consistently shown that atrazine inhibits estrogen-mediated responses, whereas in more specific in vitro systems, inhibition is seldom observed. The implication is that in vivo effects of atrazine may result from inhibition of factors that are indirectly connected to the genomic interaction of estrogen (e.g., at the receptor). Potential targets of atrazine may be downstream of the ligand-receptor binding event. Atrazine may also interact with other, less specific, factors that are necessary for the completion of the estrogen-mediated response. Moreover, the apparent inhibition of cytosolic-ER binding by atrazine may, similarly, be relatively nonspecific. Observed inhibitory responses occur only at extreme doses or concentrations, i.e., several orders of magnitude greater than the level of estradiol presence in each test system. It is probable that the inhibitory effects result from very low affinity and/or low specificity interactions, which are unlikely to occur in nature. We conclude that atrazine is not an estrogen receptor agonist, but it may be a weak antagonist, when present at a high concentration under conditions of disequilibrium with estrogen. These conditions are not expected to occur as a result of normal environmental exposure.
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Affiliation(s)
- J Charles Eldridge
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1083, USA.
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Noppe H, Ghekiere A, Verslycke T, Wulf ED, Verheyden K, Monteyne E, Polfliet K, Caeter PV, Janssen CR, De Brabander HF. Distribution and ecotoxicity of chlorotriazines in the Scheldt Estuary (B-Nl). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2007; 147:668-76. [PMID: 17140711 DOI: 10.1016/j.envpol.2006.09.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 09/04/2006] [Accepted: 09/15/2006] [Indexed: 05/12/2023]
Abstract
As part of the Endis-Risks project, the current study describes the occurrence of the chlorotriazine pesticides atrazine, simazine and terbutylazine in water, sediment and suspended matter in the Scheldt estuary (B-Nl) from 2002 to 2005 (3 samplings a year, 8 sampling points). Atrazine was found at the highest concentrations, varying from 10 to 736 ng/l in water and from 5 up to 10 ng/g in suspended matter. Simazine and terbutylazine were detected at lower concentrations. Traces of the targeted pesticides were also detected in sediments, but these were below the limit of quantification. As part of an ecotoxicological assessment, we studied the potential effect of atrazine on molting of Neomysis integer (Crustacea:Mysidacea), a resident invertebrate of the Scheldt Estuary and a proposed test organism for the evaluation of endocrine disruption. Following chronic exposure ( approximately 3 weeks), atrazine did not significantly affect mysid molting at environmentally relevant concentrations (up to 1 microg/l).
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Affiliation(s)
- Herlinde Noppe
- Ghent University, Faculty of Veterinary Medicine, Research group of Veterinary Public Health and Zoonoses, Laboratory of Chemical Analysis, Salisburylaan 133, Merelbeke, Belgium.
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