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Ubero-Pascal N, Aboal M. Cyanobacteria and Macroinvertebrate Relationships in Freshwater Benthic Communities beyond Cytotoxicity. Toxins (Basel) 2024; 16:190. [PMID: 38668615 PMCID: PMC11054157 DOI: 10.3390/toxins16040190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/01/2024] [Accepted: 04/09/2024] [Indexed: 04/29/2024] Open
Abstract
Cyanobacteria are harmful algae that are monitored worldwide to prevent the effects of the toxins that they can produce. Most research efforts have focused on direct or indirect effects on human populations, with a view to gain easy accurate detection and quantification methods, mainly in planktic communities, but with increasing interest shown in benthos. However, cyanobacteria have played a fundamental role from the very beginning in both the development of our planet's biodiversity and the construction of new habitats. These organisms have colonized almost every possible planktic or benthic environment on earth, including the most extreme ones, and display a vast number of adaptations. All this explains why they are the most important or the only phototrophs in some habitats. The negative effects of cyanotoxins on macroinvertebrates have been demonstrated, but usually under conditions that are far from natural, and on forms of exposure, toxin concentration, or composition. The cohabitation of cyanobacteria with most invertebrate groups is long-standing and has probably contributed to the development of detoxification means, which would explain the survival of some species inside cyanobacteria colonies. This review focuses on benthic cyanobacteria, their capacity to produce several types of toxins, and their relationships with benthic macroinvertebrates beyond toxicity.
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Affiliation(s)
- Nicolás Ubero-Pascal
- Department of Zoology and Physical Anthropology, Faculty of Biology, Espinardo Campus, University of Murcia, E-30100 Murcia, Spain;
| | - Marina Aboal
- Laboratory of Algology, Faculty of Biology, Espinardo Campus, University of Murcia, E-30100 Murcia, Spain
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Zhang Y, Gao J, Nie Z, Zhu H, Du J, Cao L, Shao N, Sun Y, Su S, Xu G, Xu P. Microcystin-LR induces apoptosis in Juvenile Eriocheir sinensis via the mitochondrial pathway. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 238:113528. [PMID: 35500400 DOI: 10.1016/j.ecoenv.2022.113528] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/05/2022] [Accepted: 04/13/2022] [Indexed: 06/14/2023]
Abstract
Microcystin-LR (MC-LR), the toxic substance of cyanobacteria secondary metabolism, widely exists in water environments and poses great risks to living organisms. Some toxicological assessments of MC-LR have performed at physiological and biochemical levels. However, plenty of blanks about the potential mechanism in aquatic crustacean remains. In this study, we firstly assessed the exposure toxicity of MC-LR to juvenile E. sinensis and clarified that the 96 h LD50 of MC-LR was 73.23 μg/kg. Then, hepatopancreas transcriptome profiles of MC-LR stressed crabs were constructed at 6 h post-injection and 37 differential expressed genes (DEGs) were identified. These DEGs were enriched in cytoskeleton, peroxisome and apoptosis pathways. To further reveal the toxicity of MC-LR, oxidative stress parameters (SOD, CAT, GSH-px and MDA), apoptosis genes (caspase 3, bcl-2 and bax) and apoptotic cells were detected. Significant accumulated MDA and rise-fall enzyme activities verified the oxidative stress caused by MC-LR. It is noteworthy that quantitative real-time PCR and TUNEL assay indicated that MC-LR stress-induced apoptosis via the mitochondrial pathway. Interestingly, activator protein-1 may play a crucial role in mediating the hepatotoxicity of MC-LR by regulating apoptosis and oxidative stress. Taken together, our study investigated the toxic effects and the potential molecular mechanisms of MC-LR on juvenile E. sinensis. It provided useful data for exploring the toxicity of MC-LR to aquatic crustaceans at molecular levels.
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Affiliation(s)
- Yuning Zhang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Jiancao Gao
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Zhijuan Nie
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Haojun Zhu
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Jinliang Du
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Liping Cao
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Nailin Shao
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Yi Sun
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Shengyan Su
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Gangchun Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
| | - Pao Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
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Chen L, Giesy JP, Adamovsky O, Svirčev Z, Meriluoto J, Codd GA, Mijovic B, Shi T, Tuo X, Li SC, Pan BZ, Chen J, Xie P. Challenges of using blooms of Microcystis spp. in animal feeds: A comprehensive review of nutritional, toxicological and microbial health evaluation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 764:142319. [PMID: 33069479 DOI: 10.1016/j.scitotenv.2020.142319] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/01/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
Microcystis spp., are Gram-negative, oxygenic, photosynthetic prokaryotes which use solar energy to convert carbon dioxide (CO2) and minerals into organic compounds and biomass. Eutrophication, rising CO2 concentrations and global warming are increasing Microcystis blooms globally. Due to its high availability and protein content, Microcystis biomass has been suggested as a protein source for animal feeds. This would reduce dependency on soybean and other agricultural crops and could make use of "waste" biomass when Microcystis scums and blooms are harvested. Besides proteins, Microcystis contain further nutrients including lipids, carbohydrates, vitamins and minerals. However, Microcystis produce cyanobacterial toxins, including microcystins (MCs) and other bioactive metabolites, which present health hazards. In this review, challenges of using Microcystis blooms in feeds are identified. First, nutritional and toxicological (nutri-toxicogical) data, including toxicity of Microcystis to mollusks, crustaceans, fish, amphibians, mammals and birds, is reviewed. Inclusion of Microcystis in diets caused greater mortality, lesser growth, cachexia, histopathological changes and oxidative stress in liver, kidney, gill, intestine and spleen of several fish species. Estimated daily intake (EDI) of MCs in muscle of fish fed Microcystis might exceed the provisional tolerable daily intake (TDI) for humans, 0.04 μg/kg body mass (bm)/day, as established by the World Health Organization (WHO), and is thus not safe. Muscle of fish fed M. aeruginosa is of low nutritional value and exhibits poor palatability/taste. Microcystis also causes hepatotoxicity, reproductive toxicity, cardiotoxicity, neurotoxicity and immunotoxicity to mollusks, crustaceans, amphibians, mammals and birds. Microbial pathogens can also occur in blooms of Microcystis. Thus, cyanotoxins/xenobiotics/pathogens in Microcystis biomass should be removed/degraded/inactivated sufficiently to assure safety for use of the biomass as a primary/main/supplemental ingredient in animal feed. As an ameliorative measure, antidotes/detoxicants can be used to avoid/reduce the toxic effects. Before using Microcystis in feed ingredients/supplements, further screening for health protection and cost control is required.
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Affiliation(s)
- Liang Chen
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Faculty of Water Resources and Hydroelectric Engineering, Xi'an University of Technology, Xi'an 710048, China; Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan 430072, China; University of Chinese Academy of Sciences (UCAS), Beijing 100049, China.
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan S7N5B3, Canada; Department of Environmental Science, Baylor University, Waco, TX, United States
| | - Ondrej Adamovsky
- Research Centre for Toxic Compounds in the Environment (RECETOX), Masaryk University, Kamenice 753/5, CZ-625 00 Brno, Czech Republic
| | - Zorica Svirčev
- Department of Biology and Ecology, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia; Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Jussi Meriluoto
- Department of Biology and Ecology, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia; Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Geoffrey A Codd
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK; Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, Scotland, UK
| | - Biljana Mijovic
- Faculty of Medicine, University of East Sarajevo, Studentska 5, 73 300 Foča, Republika Srpska, Bosnia and Herzegovina
| | - Ting Shi
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan 430072, China; University of Chinese Academy of Sciences (UCAS), Beijing 100049, China
| | - Xun Tuo
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan 430072, China; University of Chinese Academy of Sciences (UCAS), Beijing 100049, China; College of Chemistry, Nanchang University, Nanchang 330031, China
| | - Shang-Chun Li
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan 430072, China; University of Chinese Academy of Sciences (UCAS), Beijing 100049, China; School of Public Health, Southwest Medical University, Luzhou 646000, China
| | - Bao-Zhu Pan
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Faculty of Water Resources and Hydroelectric Engineering, Xi'an University of Technology, Xi'an 710048, China
| | - Jun Chen
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan 430072, China; University of Chinese Academy of Sciences (UCAS), Beijing 100049, China.
| | - Ping Xie
- Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS), Wuhan 430072, China; University of Chinese Academy of Sciences (UCAS), Beijing 100049, China; State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China; Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China.
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Oliveira F, Diez-Quijada L, Turkina MV, Morais J, Felpeto AB, Azevedo J, Jos A, Camean AM, Vasconcelos V, Martins JC, Campos A. Physiological and Metabolic Responses of Marine Mussels Exposed to Toxic Cyanobacteria Microcystis aeruginosa and Chrysosporum ovalisporum. Toxins (Basel) 2020; 12:toxins12030196. [PMID: 32245045 PMCID: PMC7150937 DOI: 10.3390/toxins12030196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/14/2020] [Accepted: 03/18/2020] [Indexed: 01/12/2023] Open
Abstract
Toxic cyanobacterial blooms are a major contaminant in inland aquatic ecosystems. Furthermore, toxic blooms are carried downstream by rivers and waterways to estuarine and coastal ecosystems. Concerning marine and estuarine animal species, very little is known about how these species are affected by the exposure to freshwater cyanobacteria and cyanotoxins. So far, most of the knowledge has been gathered from freshwater bivalve molluscs. This work aimed to infer the sensitivity of the marine mussel Mytilus galloprovincialis to single as well as mixed toxic cyanobacterial cultures and the underlying molecular responses mediated by toxic cyanobacteria. For this purpose, a mussel exposure experiment was outlined with two toxic cyanobacteria species, Microcystis aeruginosa and Chrysosporum ovalisporum at 1 × 105 cells/mL, resembling a natural cyanobacteria bloom. The estimated amount of toxins produced by M. aeruginosa and C. ovalisporum were respectively 0.023 pg/cell of microcystin-LR (MC-LR) and 7.854 pg/cell of cylindrospermopsin (CYN). After 15 days of exposure to single and mixed cyanobacteria, a depuration phase followed, during which mussels were fed only non-toxic microalga Parachlorella kessleri. The results showed that the marine mussel is able to filter toxic cyanobacteria at a rate equal or higher than the non-toxic microalga P. kessleri. Filtration rates observed after 15 days of feeding toxic microalgae were 1773.04 mL/ind.h (for M. aeruginosa), 2151.83 mL/ind.h (for C. ovalisporum), 1673.29 mL/ind.h (for the mixture of the 2 cyanobacteria) and 2539.25 mL/ind.h (for the non-toxic P. kessleri). Filtering toxic microalgae in combination resulted in the accumulation of 14.17 ng/g dw MC-LR and 92.08 ng/g dw CYN. Other physiological and biochemical endpoints (dry weight, byssus production, total protein and glycogen) measured in this work did not change significantly in the groups exposed to toxic cyanobacteria with regard to control group, suggesting that mussels were not affected with the toxic microalgae. Nevertheless, proteomics revealed changes in metabolism of mussels related to diet, specially evident in those fed on combined cyanobacteria. Changes in metabolic pathways related with protein folding and stabilization, cytoskeleton structure, and gene transcription/translation were observed after exposure and feeding toxic cyanobacteria. These changes occur in vital metabolic processes and may contribute to protect mussels from toxic effects of the toxins MC-LR and CYN.
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Affiliation(s)
- Flavio Oliveira
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
| | - Leticia Diez-Quijada
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n2, 41012 Seville, Spain; (L.D.-Q.); (A.J.); (A.M.C.)
| | - Maria V. Turkina
- Department of Biomedical and Clinical Sciences, Faculty of Medicine and Clinical Sciences, Linköping University, 581 83 Linköping, Sweden;
| | - João Morais
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
| | - Aldo Barreiro Felpeto
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
| | - Joana Azevedo
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
| | - Angeles Jos
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n2, 41012 Seville, Spain; (L.D.-Q.); (A.J.); (A.M.C.)
| | - Ana M. Camean
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n2, 41012 Seville, Spain; (L.D.-Q.); (A.J.); (A.M.C.)
| | - Vitor Vasconcelos
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
- Biology Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, s/n, 4169–007 Porto, Portugal
| | - José Carlos Martins
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
| | - Alexandre Campos
- CIIMAR- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal; (F.O.); (J.M.); (A.B.F.); (J.A.); (V.V.); (J.C.M.)
- Correspondence:
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Boegehold AG, Johnson NS, Kashian DR. Dreissenid (quagga and zebra mussel) veligers are adversely affected by bloom forming cyanobacteria. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 182:109426. [PMID: 31301595 DOI: 10.1016/j.ecoenv.2019.109426] [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] [Received: 03/18/2019] [Revised: 06/26/2019] [Accepted: 07/05/2019] [Indexed: 06/10/2023]
Abstract
Quagga (Dreissena rostriformis bugensis) and zebra (D. polymorpha) mussels are broadcast spawners that produce planktonic, free swimming veligers, a life history strategy dissimilar to native North American freshwater bivalves. Dreissenid veligers require highly nutritious food to grow and survive, and thus may be susceptible to increased mortality rates during harsh environmental conditions like cyanobacteria blooms. However, the impact of cyanobacteria and one of the toxins they can produce (microcystin) has not been evaluated in dreissenid veligers. Therefore, we exposed dreissenid veligers to eleven distinct cultures (isolates) of cyanobacteria representing Anabaena, Aphanizomenon, Dolichospermum, Microcystis, and Planktothrix species and the cyanotoxin microcystin to determine the lethality of cyanobacteria on dreissenid veligers. Six-day laboratory bioassays were performed in microplates using dreissenid veligers collected from the Detroit River, Michigan, USA. Veligers were exposed to increasing concentrations of cyanobacteria and microcystin using the green algae Chlorella minutissima as a control. Based on dose response curves formulated from a Probit model, the LC50 values for cyanobacteria used in this study range between 15.06 and 135.06 μg/L chlorophyll-a, with the LC50 for microcystin-LR at 13.03 μg/L. Because LC50 values were within ranges observed in natural waterbodies, it is possible that dreissenid recruitment may be suppressed when veliger abundances overlap with seasonal cyanobacteria blooms. Thus, the toxicity of cyanobacteria to dreissenid veligers may be useful to include in models forecasting dreissenid mussel abundance and spread.
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Affiliation(s)
- Anna G Boegehold
- Wayne State University Department of Biological Sciences, 5047 Gullen Mall, Detroit, MI, 48202, USA
| | - Nicholas S Johnson
- U.S. Geological Survey, Great Lakes Science Center, Hammond Bay Biological Station, 11188 Ray Road Millersburg, MI, 49759, USA
| | - Donna R Kashian
- Wayne State University Department of Biological Sciences, 5047 Gullen Mall, Detroit, MI, 48202, USA.
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Gene SM, Shahmohamadloo RS, Ortiz X, Prosser RS. Effect of Microcystis aeruginosa-Associated Microcystin-LR on the Survival of 2 Life Stages of Freshwater Mussel (Lampsilis siliquoidea). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2019; 38:2137-2144. [PMID: 31233235 DOI: 10.1002/etc.4527] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/10/2019] [Accepted: 06/18/2019] [Indexed: 06/09/2023]
Abstract
Microcystin-LR is a toxin commonly produced by the cyanobacterium Microcystis aeruginosa. It is present in harmful algal blooms and is a concern for both human and environmental health in Canadian freshwater systems. Previous studies have investigated the toxicity of microcystin-LR to other organisms such as fish; however, it is important to assess its toxicity to native freshwater mussels (family Unionidae), which are considered imperiled. The present study examined the toxicity of microcystin-LR to fatmucket mussels (Lampsilis siliquoidea) at 2 different life stages. Juvenile mussels were exposed to microcystin-LR in a 28-d chronic test, and glochidia underwent a 72-h acute toxicity test. There was no significant relationship between glochidia viability and microcystin-LR concentration. The median lethal concentration (LC50) value for juvenile mussels after 28 d of exposure was 2.1 µg/L. To determine the environmental relevance of the observed toxicity, an environmental exposure distribution was created using Canadian and Canadian-US Great Lakes microcystin measurements. The 28-d LC50 value (2.1 µg/L) was greater than those values that occurred in the environment 95% of the time; however, the LC10 (0.45 µg/L) and LC25 (0.97 μg/L) values were not greater than the measured microcystin environmental values. This finding indicates that microcystins may exert toxic effects on juvenile mussels at environmentally relevant concentrations. Further investigation should be considered in terms of prolonged exposure to persistent microcystin-LR, and toxicity to sensitive species at different life stages. Environ Toxicol Chem 2019;38:2137-2144. © 2019 SETAC.
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Affiliation(s)
- Samantha May Gene
- School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada
| | | | - Xavier Ortiz
- Laboratory Services Branch, Ontario Ministry of the Environment, Conservation, and Parks, Toronto, Ontario, Canada
- School of Environmental Sciences, Queen's University, Kingston, Ontario, Canada
| | - Ryan S Prosser
- School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada
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