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Berger ML, Shaw SD, Rolsky CB, Chen D, Sun J, Rosing-Asvid A, Granquist SM, Simon M, Bäcklin BM, Roos AM. Alternative and legacy flame retardants in marine mammals from three northern ocean regions. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 335:122255. [PMID: 37517638 DOI: 10.1016/j.envpol.2023.122255] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/13/2023] [Accepted: 07/24/2023] [Indexed: 08/01/2023]
Abstract
Flame retardants are globally distributed contaminants that have been linked to negative health effects in humans and wildlife. As top predators, marine mammals bioaccumulate flame retardants and other contaminants in their tissues which is one of many human-imposed factors threatening population health. While some flame retardants, such as the polybrominated diphenyl ethers (PBDE), have been banned because of known toxicity and environmental persistence, limited data exist on the presence and distribution of current-use alternative flame retardants in marine mammals from many industrialized and remote regions of the world. Therefore, this study measured 44 legacy and alternative flame retardants in nine marine mammal species from three ocean regions: the Northwest Atlantic, the Arctic, and the Baltic allowing for regional, species, age, body condition, temporal, and tissue comparisons to help understand global patterns. PBDE concentrations were 100-1000 times higher than the alternative brominated flame retardants (altBFRs) and Dechloranes. 2,2',4,5,5'-pentabromobiphenyl (BB-101) and hexabromobenzene (HBBZ) were the predominant altBFRs, while Dechlorane-602 was the predominant Dechlorane. This manuscript also reports only the second detection of hexachlorocyclopentadienyl-dibromocyclooctane (HCDBCO) in marine mammals. The NW Atlantic had the highest PBDE concentrations followed by the Baltic and Arctic which reflects greater historical use of PBDEs in North America compared to Europe and greater industrialization of North America and Baltic countries compared to the Arctic. Regional patterns for other compounds were more complicated, and there were significant interactions among species, regions, body condition and age class. Lipid-normalized PBDE concentrations in harbor seal liver and blubber were similar, but HBBZ and many Dechloranes had higher concentrations in liver, indicating factors other than lipid dynamics affect the distribution of these compounds. The health implications of contamination by this mixture of compounds are of concern and require further research.
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Affiliation(s)
- Michelle L Berger
- Shaw Institute, PO Box 1652, 55 Main Street, Blue Hill, ME, 04614, USA.
| | - Susan D Shaw
- Shaw Institute, PO Box 1652, 55 Main Street, Blue Hill, ME, 04614, USA
| | - Charles B Rolsky
- Shaw Institute, PO Box 1652, 55 Main Street, Blue Hill, ME, 04614, USA
| | - Da Chen
- School of Environment and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, Guangdong, 510632, China; Cooperative Wildlife Research Laboratory and Department of Zoology, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Jiachen Sun
- School of Environment and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, Guangdong, 510632, China; College of Marine Life Science, Ocean University of China, CN-266003, Qingdao, China
| | - Aqqalu Rosing-Asvid
- Greenland Climate Research Centre, Greenland Institute of Natural Resources, Kivioq 2, PO Box 570, 3900, Nuuk, Greenland
| | - Sandra Magdalena Granquist
- Seal Research Department, The Icelandic Seal Center, Höfðabraut 6, 530 Hvammstangi, Iceland; Marine and Freshwater Research Institute, Fornubúðir 5, 220 Hafnarfjörður, Iceland
| | - Malene Simon
- Greenland Climate Research Centre, Greenland Institute of Natural Resources, Kivioq 2, PO Box 570, 3900, Nuuk, Greenland
| | - Britt-Marie Bäcklin
- Department of Environmental Research and Monitoring, Swedish Museum of Natural History, PO Box 104 05 Stockholm, Sweden
| | - Anna Maria Roos
- Greenland Climate Research Centre, Greenland Institute of Natural Resources, Kivioq 2, PO Box 570, 3900, Nuuk, Greenland; Department of Environmental Research and Monitoring, Swedish Museum of Natural History, PO Box 104 05 Stockholm, Sweden
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Yan Z, Feng C, Jin X, Wang F, Liu C, Li N, Qiao Y, Bai Y, Wu F, Giesy JP. Organophosphate esters cause thyroid dysfunction via multiple signaling pathways in zebrafish brain. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2022; 12:100198. [PMID: 36157343 PMCID: PMC9500371 DOI: 10.1016/j.ese.2022.100198] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/01/2022] [Accepted: 06/01/2022] [Indexed: 05/04/2023]
Abstract
Organophosphate esters (OPEs) are widespread in various environmental media, and can disrupt thyroid endocrine signaling pathways. Mechanisms by which OPEs disrupt thyroid hormone (TH) signal transduction are not fully understood. Here, we present in vivo-in vitro-in silico evidence establishing OPEs as environmental THs competitively entering the brain to inhibit growth of zebrafish via multiple signaling pathways. OPEs can bind to transthyretin (TTR) and thyroxine-binding globulin, thereby affecting the transport of TH in the blood, and to the brain by TTR through the blood-brain barrier. When GH3 cells were exposed to OPEs, cell proliferation was significantly inhibited given that OPEs are competitive inhibitors of TH. Cresyl diphenyl phosphate was shown to be an effective antagonist of TH. Chronic exposure to OPEs significantly inhibited the growth of zebrafish by interfering with thyroperoxidase and thyroglobulin to inhibit TH synthesis. Based on comparisons of modulations of gene expression with the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases, signaling pathways related to thyroid endocrine functions, such as receptor-ligand binding and regulation of hormone levels, were identified as being affected by exposure to OPEs. Effects were also associated with the biosynthesis and metabolism of lipids, and neuroactive ligand-receptor interactions. These findings provide a comprehensive understanding of the mechanisms by which OPEs disrupt thyroid pathways in zebrafish.
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Key Words
- AChE, acetylcholinesterase
- ANOVA, analysis of variance
- BCF, bioconcentration factor
- BFR, brominated flame retardant
- CD-FBS, charcoal-dextran-treated fetal bovine serum
- CDP, cresyl diphenyl phosphate
- Competitive inhibition assay
- DEG, differentially expressed gene
- DKA, β-diketone antibiotic
- DMSO, dimethyl sulfoxide
- EAS, estrogen
- FBS, fetal bovine serum
- GAPDH, glyceraldehyde-3-phosphate dehydrogenase
- GO, Gene Ontology
- HPLC-MS/MS, high-performance liquid chromatograph interfaced with a mass spectrometer
- HPT, hypothalamic–pituitary–thyroid
- HS, horse serum
- KEGG, Kyoto Encyclopedia of Genes and Genomes
- MAPK, mitogen-activated protein kinase
- Molecular docking simulation
- NIS, Na+/I− symporter
- OD490, optical density
- OPE, organophosphate ester
- OPFR, organophosphate flame retardant
- Organophosphate ester
- P/S, penicillin–streptomycin
- PBDE, polybrominated diphenyl ether
- PBS, phosphate-buffered saline
- RIC20/50, concentration inhibiting 20%/50%
- T4, thyroxin
- TBG, thyroxine-binding globulin
- TCIPP, tris(2-chloroisopropyl) phosphate
- TDCIPP, tris(1,3-dichloro-2-propyl) phosphate (TDCIPP)
- TDCIPP-d15, tris(1,3-dichloroisopropyl) phosphate-D15
- TG, thyroglobulin
- TH, thyroid hormone
- THR, thyroid hormone receptor
- TIPP, tris(isopropyl) phosphate
- TPHP, triphenyl phosphate
- TPO, thyroperoxidase
- TRβ, thyroid hormone receptor β
- TTR, transthyretin
- Thyroid endocrine function
- Transcriptome sequencing
- androgen, and steroidogenesis
- cga, glycoprotein hormone
- qRT-PCR, quantitative real-time PCR
- tshβa, thyroid-stimulating hormone beta subunit a
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Affiliation(s)
- Zhenfei Yan
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- College of Environment, Hohai University, Nanjing, 210098, China
| | - Chenglian Feng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- Corresponding author.
| | - Xiaowei Jin
- China National Environmental Monitoring Centre, Beijing, 100012, China
- Corresponding author.
| | - Fangkun Wang
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Taian, 271018, China
| | - Cong Liu
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Taian, 271018, China
| | - Na Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Yu Qiao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yingchen Bai
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- College of Environment, Hohai University, Nanjing, 210098, China
| | - John P. Giesy
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, Canada
- Toxicology Centre, University of Saskatchewan, Saskatoon, SK, Canada
- Department of Environmental Sciences, Baylor University, Waco, TX, USA
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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: 66] [Impact Index Per Article: 33.0] [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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Dominique M, Letcher RJ, Rutter A, Langlois VS. Comparative review of the distribution and burden of contaminants in the body of polar bears. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:32456-32466. [PMID: 32556983 DOI: 10.1007/s11356-020-09193-2] [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] [Received: 07/12/2019] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
Historical (or legacy) contaminants, such as metals and persistent organic pollutants (POPs; e.g., polychlorinated biphenyls) have been measured in circumpolar subpopulations of polar bears, especially from Hudson Bay, East Greenland, and Svalbard, but substantially less is currently known about new and/or emerging contaminants such as polychlorinated naphthalenes, current-use pesticides, organotins, and polycyclic aromatic compounds (PACs). The polar bear (Ursus maritimus) is an apex Arctic predator that accumulates high levels of bioaccumulative POPs and mercury (Hg), but there is currently no comprehensive profiling of the present knowledge on contaminants in tissue and body compartments in polar bears. Based on current literature reports and data, and including archived museum samples (as far back as the 1300s) and up to 2018, the aim of this review is to utilize available data to examine the comparative distribution and burden of mainly lipophilic contaminants in kidney, liver, fat, and other body compartments, such as milk, blood, and brain. Highlight outcomes from this review include the following: (1) the kidneys are one of the most important tissue depots of contaminants in polar bears; (2) there is a critical lack of data concerning the presence of metals of concern (other than Hg); and (3) there currently are no data available on the concentrations of many newer and emerging contaminants, such as PACs, which is especially relevant given the increasing oil and gas development in regions, such as the Beaufort Sea (Canada). Additionally, given the vulnerability of polar bear populations worldwide, there is a need to develop non-invasive approaches to monitor contaminant exposure in polar bears.
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Affiliation(s)
- Mélanie Dominique
- Centre Eau Terre Environnement, Institut national de la recherche scientifique (INRS), Québec City, QC, Canada
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON, Canada
| | - Allison Rutter
- School of Environmental Studies, Queen's University, Kingston, ON, Canada
| | - Valerie S Langlois
- Centre Eau Terre Environnement, Institut national de la recherche scientifique (INRS), Québec City, QC, Canada.
- Ecotoxicology and Wildlife Health Division, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON, Canada.
- Ecotoxicogenomics and Endocrine Disruption, Centre Eau Terre Environnement, Institut national de la recherche scientifique (INRS), 490, rue de la Couronne, Québec, QC, G1K 9A9, Canada.
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5
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Guo LC, Yu S, Wu D, Huang J, Liu T, Xiao J, Huang W, Gao Y, Li X, Zeng W, Rutherford S, Ma W, Zhang Y, Lin L. Disruption of thyroid hormone regulated proteins and gene expression by polychlorinated biphenyls, polybrominated diphenyl ethers and new flame retardants in residents of an e-waste region. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 254:112925. [PMID: 31454572 DOI: 10.1016/j.envpol.2019.07.093] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 07/18/2019] [Accepted: 07/18/2019] [Indexed: 06/10/2023]
Abstract
Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and new flame retardants (NFRs) are known thyroid hormone (TH) disruptors, but their disrupting mechanisms in humans are not completely understood. In this study, we aimed to explore the disrupting mechanisms of the aforementioned chemicals via examining TH-regulated proteins and gene expression in human serum. Adult participants from an e-waste dismantling (exposed group) and a control region (control group) in South China provided blood samples for the research. Some compounds of PCBs, PBDEs, and NFRs showed strong binding affinity to the thyroid-stimulating hormone (TSH), thyroglobulin, thyroxine-binding globulin (TBG), gene expression of TH receptor α (TRα) and β, and iodothyronine deiodinase I (ID1). The highly exposed individuals had lower levels of TBG, TSH, and expression of TRα, but higher expression of ID1 than those of the control group. The disruption of TH-regulated proteins and gene expression suggested the exertion of different and, at times, even contradictory effects on TH disruption. However, no statistically significant difference was found in the TH levels between the exposed and the control group, implying that the TH disruption induced by these chemicals depends on the combined influence of multiple mechanisms. Gene expression appears to be an effective approach for investigations of TH disruption and the potential health effects.
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Affiliation(s)
- Ling-Chuan Guo
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Shengbing Yu
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - De Wu
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Jinxu Huang
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Tao Liu
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Jianpeng Xiao
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China; School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Weixiong Huang
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Yanhong Gao
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Xing Li
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China; School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Weilin Zeng
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | | | - Wenjun Ma
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
| | - Yonghui Zhang
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China.
| | - Lifeng Lin
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China
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Ochiai M, Iida M, Agusa T, Takaguchi K, Fujii S, Nomiyama K, Iwata H. Effects of 4-Hydroxy-2,3,3',4',5-Pentachlorobiphenyl (4-OH-CB107) on Liver Transcriptome in Rats: Implication in the Disruption of Circadian Rhythm and Fatty Acid Metabolism. Toxicol Sci 2019; 165:118-130. [PMID: 29788408 DOI: 10.1093/toxsci/kfy123] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) have been detected in tissues of both wild animals and humans. Several previous studies have suggested adverse effects of OH-PCBs on the endocrine and nervous systems in mammals. However, there have been no studies on transcriptome analysis of the effects of OH-PCBs, and thus, the whole picture and mechanisms underlying the adverse effects induced by OH-PCBs are still poorly understood. We therefore investigated the mRNA expression profile in the liver of adult male Wistar rats treated with 4-hydroxy-2,3,3',4',5-pentachlorobiphenyl (4-OH-CB107) to explore the genes responsive to OH-PCBs and to understand the potential effects of the chemical. Next-generation RNA sequencing analysis revealed changes in the expression of genes involved in the circadian rhythm and fatty acid metabolism, such as nuclear receptor subfamily 1, group D, member 1, aryl hydrocarbon receptor nuclear translocator-like protein 1, cryptochrome circadian clock 1, and enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase, in 4-OH-CB107-treated rats. In addition, biochemical analysis of the plasma revealed a dose-dependent increase in the leucine aminopeptidase, indicating the onset of liver damage. These results suggest that OH-PCB exposure may induce liver injury as well as disrupt the circadian rhythm and peroxisome proliferator-activated receptor-related fatty acid metabolism.
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Affiliation(s)
- Mari Ochiai
- Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Midori Iida
- Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577, Japan
- Department of Bioscience and Bioinformatics, Kyusyu Institute of Technology, Iizuka, Fukuoka 820-0067, Japan
| | - Tetsuro Agusa
- Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Kumamoto 862-8502, Japan
| | - Kohki Takaguchi
- Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Satoshi Fujii
- Department of Bioscience and Bioinformatics, Kyusyu Institute of Technology, Iizuka, Fukuoka 820-0067, Japan
| | - Kei Nomiyama
- Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Hisato Iwata
- Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime 790-8577, Japan
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7
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Simond AE, Houde M, Lesage V, Michaud R, Zbinden D, Verreault J. Associations between organohalogen exposure and thyroid- and steroid-related gene responses in St. Lawrence Estuary belugas and minke whales. MARINE POLLUTION BULLETIN 2019; 145:174-184. [PMID: 31590774 DOI: 10.1016/j.marpolbul.2019.05.029] [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: 12/10/2018] [Revised: 05/12/2019] [Accepted: 05/13/2019] [Indexed: 06/10/2023]
Abstract
Elevated concentrations of persistent organic pollutants (POPs) and emerging halogenated flame retardants (HFRs) have been reported in tissues of the endangered St. Lawrence Estuary (Canada) beluga population as well as in minke whales visiting that same feeding area. This study examined the linkages between blubber concentrations of POPs and emerging HFRs, and transcription in skin of genes involved in the regulation of thyroid and steroid axes in belugas and minke whales from the St. Lawrence Estuary. In belugas, concentrations of PCBs, OCs and hexabromobenzene (HBB) were positively correlated with the transcription of thyroid- and/or steroid-related genes, while Dec-604 CB concentrations were negatively associated with the transcription of glucocorticoid and thyroid genes. In minke whales, PBDE concentrations changed positively with Esrβ transcript levels and HBB concentrations negatively with Nr3c1 transcripts. Present results suggest that several biological functions including reproduction and energetic metabolism may represent potential targets for organohalogens in these whales.
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Affiliation(s)
- Antoine E Simond
- Centre de recherche en toxicologie de l'environnement (TOXEN), Département des sciences biologiques, Université du Québec à Montréal, P.O. Box 8888, Succursale Centre-ville, Montreal, QC H3C 3P8, Canada
| | - Magali Houde
- Environment and Climate Change Canada, 105 McGill Street, Montreal, QC H2Y 2E7, Canada
| | - Véronique Lesage
- Maurice Lamontagne Institute, Fisheries and Oceans Canada, P.O. Box 1000, 850 route de la Mer, Mont-Joli, QC G5H 3Z4, Canada
| | - Robert Michaud
- Groupe de Recherche et d'Éducation sur les Mammifères Marins (GREMM), 870 avenue Salaberry, Bureau R24, Québec, QC G1R 2T9, Canada
| | - Dany Zbinden
- Mériscope, 833 rue du Quai, Portneuf-sur-Mer, QC G0T 1P0, Canada
| | - Jonathan Verreault
- Centre de recherche en toxicologie de l'environnement (TOXEN), Département des sciences biologiques, Université du Québec à Montréal, P.O. Box 8888, Succursale Centre-ville, Montreal, QC H3C 3P8, Canada.
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8
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Carlsson G. Effect-based environmental monitoring for thyroid disruption in Swedish amphibian tadpoles. ENVIRONMENTAL MONITORING AND ASSESSMENT 2019; 191:454. [PMID: 31222463 PMCID: PMC6586702 DOI: 10.1007/s10661-019-7590-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 06/04/2019] [Indexed: 06/09/2023]
Abstract
It is well-known that the metamorphosis process in amphibians is dependent on thyroid hormones. Laboratory studies have shown that several environmental contaminants can affect the function of thyroid hormones leading to alterations in the amphibian metamorphosis. The basic idea of the present study was to elucidate if the amphibian metamorphosis might be a useful tool as biomarker for effect-based environmental monitoring, examining wild tadpoles for potential thyroid hormone disruption. A laboratory test was performed to identify the responses from exposure to 6-propylthiouracil (PTU), which has a well-known mechanism on the thyroid system, on Swedish tadpoles from the Rana genus. This was followed by an environmental monitoring study where tadpoles of Rana arvalis, R. temporaria, and Bufo bufo were sampled from various sites in Sweden. Morphological data such as body weight, histopathological measurements of the thyroid glands, and environmental parameters were recorded. The results revealed that Rana tadpoles respond similar as other amphibians to PTU exposure, with interrupted development and increased size relative to the developmental stage. Data on some wild tadpoles showed similar features as the PTU exposed, such as high body weight, thus suggesting potential thyroid disrupting effects. However, histological evaluation of thyroid glands and pesticide analyses of the water revealed no clear evidence of chemical interactions. To a minor degree, the changes in body weight may be explained by natural circumstances such as pH, forest cover, and temperature. The present study cannot fully explain whether the high body weights recorded in some tadpoles have natural or chemical explanations. However, the study reveals that it is clearly achievable to catch tadpoles in suitable stages for the use in this type of biomonitoring and that the use of these biomarkers for assessment of thyroid disruption seems to be highly relevant.
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Affiliation(s)
- Gunnar Carlsson
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 750 07, Uppsala, Sweden.
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9
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Routti H, Atwood TC, Bechshoft T, Boltunov A, Ciesielski TM, Desforges JP, Dietz R, Gabrielsen GW, Jenssen BM, Letcher RJ, McKinney MA, Morris AD, Rigét FF, Sonne C, Styrishave B, Tartu S. State of knowledge on current exposure, fate and potential health effects of contaminants in polar bears from the circumpolar Arctic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 664:1063-1083. [PMID: 30901781 DOI: 10.1016/j.scitotenv.2019.02.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/01/2019] [Accepted: 02/02/2019] [Indexed: 05/03/2023]
Abstract
The polar bear (Ursus maritimus) is among the Arctic species exposed to the highest concentrations of long-range transported bioaccumulative contaminants, such as halogenated organic compounds and mercury. Contaminant exposure is considered to be one of the largest threats to polar bears after the loss of their Arctic sea ice habitat due to climate change. The aim of this review is to provide a comprehensive summary of current exposure, fate, and potential health effects of contaminants in polar bears from the circumpolar Arctic required by the Circumpolar Action Plan for polar bear conservation. Overall results suggest that legacy persistent organic pollutants (POPs) including polychlorinated biphenyls, chlordanes and perfluorooctane sulfonic acid (PFOS), followed by other perfluoroalkyl compounds (e.g. carboxylic acids, PFCAs) and brominated flame retardants, are still the main compounds in polar bears. Concentrations of several legacy POPs that have been banned for decades in most parts of the world have generally declined in polar bears. Current spatial trends of contaminants vary widely between compounds and recent studies suggest increased concentrations of both POPs and PFCAs in certain subpopulations. Correlative field studies, supported by in vitro studies, suggest that contaminant exposure disrupts circulating levels of thyroid hormones and lipid metabolism, and alters neurochemistry in polar bears. Additionally, field and in vitro studies and risk assessments indicate the potential for adverse impacts to polar bear immune functions from exposure to certain contaminants.
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Affiliation(s)
- Heli Routti
- Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø, Norway.
| | - Todd C Atwood
- U.S. Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| | - Thea Bechshoft
- Department of Bioscience, Arctic Research Centre (ARC), Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Andrei Boltunov
- Marine Mammal Research and Expedition Center, 36 Nahimovskiy pr., Moscow 117997, Russia
| | - Tomasz M Ciesielski
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Jean-Pierre Desforges
- Department of Bioscience, Arctic Research Centre (ARC), Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Rune Dietz
- Department of Bioscience, Arctic Research Centre (ARC), Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | | | - Bjørn M Jenssen
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; Department of Bioscience, Arctic Research Centre (ARC), Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark; Department of Arctic Technology, University Centre in Svalbard, PO Box 156, NO-9171 Longyearbyen, Norway
| | - Robert J Letcher
- Ecotoxicology and Wildlife Heath Division, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, 1125 Colonel By Dr., Ottawa, Ontario K1A 0H3, Canada
| | - Melissa A McKinney
- Department of Natural Resource Sciences, McGill University, Ste.-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Adam D Morris
- Ecotoxicology and Wildlife Heath Division, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, 1125 Colonel By Dr., Ottawa, Ontario K1A 0H3, Canada
| | - Frank F Rigét
- Department of Bioscience, Arctic Research Centre (ARC), Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Christian Sonne
- Department of Bioscience, Arctic Research Centre (ARC), Faculty of Science and Technology, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Bjarne Styrishave
- Toxicology and Drug Metabolism Group, Department of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen OE, Denmark
| | - Sabrina Tartu
- Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø, Norway
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10
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Chen X, Fang M, Chernick M, Wang F, Yang J, Yu Y, Zheng N, Teraoka H, Nanba S, Hiraga T, Hinton DE, Dong W. The case for thyroid disruption in early life stage exposures to thiram in zebrafish (Danio rerio). Gen Comp Endocrinol 2019; 271:73-81. [PMID: 30408483 DOI: 10.1016/j.ygcen.2018.11.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/07/2018] [Accepted: 11/04/2018] [Indexed: 12/17/2022]
Abstract
Thiram, a pesticide in the dithiocarbamate chemical family, is widely used to prevent fungal disease in seeds and crops. Its off-site movement to surface waters occurs and may place aquatic organisms at potential harm. Zebrafish embryos were used for investigation of acute (1 h) thiram exposure (0.001-10 µM) at various developmental stages. Survival decreased at 1 µM and 10 µM and hatching was delayed at 0.1 µM and 1 µM. Notochord curvatures were seen at 0.1 and 1 μM thiram when exposure was initiated at 2 and at 10 hpf. Similar notochord curvatures followed exposure to the known TPO inhibitor, methimazole (MMI). Changes were absent in embryos exposed at later stages, i.e., 12 hpf. In embryos exposed to 0.1 or 1 μM at 10 hpf, levels of the thyroid enzyme, Deiodinase 3, increased by 12 hpf. Thyroid peroxide (TPO), important in T4 synthesis, decreased by 48 hpf in embryos exposed to 1 µM at 10 hpf. Thiram toxicity was stage-dependent and early life stage exposure may be responsible for adverse effects seen later. These effects may be due to impacts on the thyroid via regulation of specific thyroid genes including TPO and Deiodinase 3.
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Affiliation(s)
- Xing Chen
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia 028000, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Key Laboratory of Maricultural Organism Disease Control, Ministry of Agriculture, Qingdao Key Laboratory of Mariculture Epidemiology and Biosecurity, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Mingliang Fang
- Nicholas School of the Environment, Duke University, Durham, NC 27705, USA; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Melissa Chernick
- Nicholas School of the Environment, Duke University, Durham, NC 27705, USA
| | - Feng Wang
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia 028000, China
| | - Jingfeng Yang
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia 028000, China
| | - Yongli Yu
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia 028000, China
| | - Na Zheng
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun, Jilin 130012, China
| | - Hiroki Teraoka
- School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan
| | - Satomi Nanba
- School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan
| | - Takeo Hiraga
- School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan
| | - David E Hinton
- Nicholas School of the Environment, Duke University, Durham, NC 27705, USA.
| | - Wu Dong
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia 028000, China; Nicholas School of the Environment, Duke University, Durham, NC 27705, USA.
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11
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Grønnestad R, Villanger GD, Polder A, Kovacs KM, Lydersen C, Jenssen BM, Borgå K. Effects of a complex contaminant mixture on thyroid hormones in breeding hooded seal mothers and their pups. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 240:10-16. [PMID: 29729564 DOI: 10.1016/j.envpol.2018.04.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 04/10/2018] [Accepted: 04/10/2018] [Indexed: 06/08/2023]
Abstract
There is a general lack of information on the possible effects of perfluoroalkyl substances (PFASs) on thyroid hormones (THs) in wildlife species. The effects of PFASs, which are known endocrine disruptors, on the TH homeostasis in hooded seals (Cystophora cristata) have yet to be investigated. Previously, correlations were found between plasma thyroid hormone (TH) concentrations in hooded seals, and organohalogen contaminants (OHCs) and hydroxyl (OH)-metabolites. Because animals are exposed to multiple contaminants simultaneously in nature, the effects of the complex contaminant mixtures that they accumulate should be assessed. Herein, we analyse relationships between plasma concentrations of multiple contaminants including protein-associated PFASs, hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs) and lipid soluble OHCs and plasma concentrations of free and total THs, i.e. triiodothyronine (FT3, TT3) and thyroxine (FT4, TT4) in hooded seal mothers and their pups. The perfluoroalkyl carboxylates (PFCAs) were the most important predictors for FT3 concentrations and TT3:FT3 ratios in the mothers. The FT3 levels decreased with increasing PFCA levels, while the TT3:FT3 ratios increased. In the pups, hexachlorocyclohexanes (HCHs) were the most important predictors for TT3:FT3 ratios, increasing with increasing HCHs levels. Additionally, perfluoroalkyl sulfonates (PFSAs) and PFCAs were important predictors for FT4:FT3 ratios in hooded seal pups, and the ratio increased with increasing concentrations. The study suggests that PFASs contribute to thyroid disruption in hooded seals exposed to complex contaminant mixtures that include chlorinated and fluorinated organic compounds.
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Affiliation(s)
- Randi Grønnestad
- Department of Biosciences, University of Oslo, Oslo, Norway; Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Gro D Villanger
- Department of Child Health, Norwegian Institute of Public Health, Oslo, Norway; Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | | | - Kit M Kovacs
- Norwegian Polar Institute, Fram Centre, Tromsø, Norway
| | | | - Bjørn M Jenssen
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway; Department of Arctic Biology, The University Centre in Svalbard, Longyearbyen, Norway
| | - Katrine Borgå
- Department of Biosciences, University of Oslo, Oslo, Norway.
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12
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Granby K, Rainieri S, Rasmussen RR, Kotterman MJJ, Sloth JJ, Cederberg TL, Barranco A, Marques A, Larsen BK. The influence of microplastics and halogenated contaminants in feed on toxicokinetics and gene expression in European seabass (Dicentrarchus labrax). ENVIRONMENTAL RESEARCH 2018; 164:430-443. [PMID: 29573718 DOI: 10.1016/j.envres.2018.02.035] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 02/22/2018] [Accepted: 02/25/2018] [Indexed: 06/08/2023]
Abstract
When microplastics pollute fish habitats, it may be ingested by fish, thereby contaminating fish with sorbed contaminants. The present study investigates how combinations of halogenated contaminants and microplastics associated with feed are able to alter toxicokinetics in European seabass and affect the fish. Microplastic particles (2%) were added to the feed either with sorbed contaminants or as a mixture of clean microplastics and chemical contaminants, and compared to feed containing contaminants without microplastics. For the contaminated microplastic diet, the accumulation of polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) in fish was significantly higher, increasing up to 40 days of accumulation and then reversing to values comparable to the other diets at the end of accumulation. The significant gene expression results of liver (cyp1a, il1β, gstα) after 40 days of exposure indicate that microplastics might indeed exacerbate the toxic effects (liver metabolism, immune system, oxidative stress) of some chemical contaminants sorbed to microplastics. Seabass quickly metabolised BDE99 to BDE47 by debromination, probably mediated by deiodinase enzymes, and unlike other contaminants, this metabolism was unaffected by the presence of microplastics. For the other PCBs and BFRs, the elimination coefficients were significantly lower in fish fed the diet with contaminants sorbed to microplastic compared to the other diets. The results indicate that microplastics affects liver detoxification and lipid distribution, both of which affect the concentration of contaminants.
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Affiliation(s)
- Kit Granby
- Technical University of Denmark (DTU), National Food Institute, Kemitorvet, 2800 Lyngby, Denmark.
| | - Sandra Rainieri
- AZTI, Food Research Division, Astondo bidea 609, 48160 Derio, Spain
| | - Rie Romme Rasmussen
- Technical University of Denmark (DTU), National Food Institute, Kemitorvet, 2800 Lyngby, Denmark
| | - Michiel J J Kotterman
- Institute for Marine Resources and Ecosystem Studies (IMARES), Wageningen University and Research Center, Haringkade 1, 1976 CP IJmuiden, The Netherlands
| | - Jens Jørgen Sloth
- Technical University of Denmark (DTU), National Food Institute, Kemitorvet, 2800 Lyngby, Denmark
| | - Tommy Licht Cederberg
- Technical University of Denmark (DTU), National Food Institute, Kemitorvet, 2800 Lyngby, Denmark
| | - Alex Barranco
- AZTI, Food Research Division, Astondo bidea 609, 48160 Derio, Spain
| | - António Marques
- Portuguese Institute for the Sea and Atmosphere (IPMA), Division of Aquaculture and Upgrading, Avenida de Brasilia, 1449-006 Lisboa, Portugal; Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Porto, Portugal
| | - Bodil Katrine Larsen
- Technical University of Denmark (DTU), National Institute of Aquatic Resources, Section for Aquaculture, Niels Juelsvej 30, 9850 Hirtshals, Denmark
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13
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François A, Verreault J. Interaction between deca-BDE and hepatic deiodinase in a highly PBDE-exposed bird. ENVIRONMENTAL RESEARCH 2018; 163:108-114. [PMID: 29433018 DOI: 10.1016/j.envres.2018.01.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 12/21/2017] [Accepted: 01/04/2018] [Indexed: 06/08/2023]
Abstract
Studies have shown that debromination of the major component in the deca-brominated diphenyl ether mixture (deca-BDE), BDE-209, occurs in vivo in birds. Recent work from our laboratory on breeding ring-billed gulls (Larus delawarensis) exposed to elevated PBDE concentrations in the densely-populated metropolis of Montreal (Canada) further suggests that BDE-209 debromination is potentially catalyzed by deiodinases in liver microsomes. The first objective of this study was to determine if type 1 deiodinase (D1) was involved in the in vitro debromination of BDE-209 in liver microsomes of ring-billed gulls. The second objective was to determine if there was an interaction between D1 and BDE-209 using an in vitro D1 activity assay. No depletion of BDE-209 was observed in gull liver microsomes. A significant 42% increase in total D1 activity was found in gull liver microsomes at the medium BDE-209 concentration (1.0 nM), although not at the low (0.5 nM) or high (2.5 nM) concentrations, suggesting potential non-dose related interaction with D1. Moreover, no correlation was found between total D1 activity in liver microsomes and plasma thyroid hormone levels, although there was a negative relationship between plasma BDE-209 concentrations and FT3 levels. Results from this study suggest that debromination of BDE-209 did not occur using present in vitro assay conditions, although indicated potential interaction with D1 that may have implication on circulating thyroid hormone status.
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Affiliation(s)
- Anthony François
- Centre de recherche en toxicologie de l'environnement (TOXEN), Département des sciences biologiques, Université du Québec à Montréal, P.O. Box 8888, Succursale Centre-ville, Montreal, QC, Canada H3C 3P8
| | - Jonathan Verreault
- Centre de recherche en toxicologie de l'environnement (TOXEN), Département des sciences biologiques, Université du Québec à Montréal, P.O. Box 8888, Succursale Centre-ville, Montreal, QC, Canada H3C 3P8.
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14
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Hoydal KS, Styrishave B, Ciesielski TM, Letcher RJ, Dam M, Jenssen BM. Steroid hormones and persistent organic pollutants in plasma from North-eastern Atlantic pilot whales. ENVIRONMENTAL RESEARCH 2017; 159:613-621. [PMID: 28918287 DOI: 10.1016/j.envres.2017.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 08/30/2017] [Accepted: 09/08/2017] [Indexed: 06/07/2023]
Abstract
Persistent organic pollutants (POPs) are known to have endocrine disruptive effects, interfering with endogenous steroid hormones. The present study examined nine steroid hormones and their relationships with the concentrations of selected POPs in pilot whales (Globicephala melas) from the Faroe Islands, NE Atlantic. The different steroids were detected in 15 to all of the 26 individuals. High concentrations of progesterone (83.3-211.7pmol/g) and pregnenolone (PRE; 4.68-5.69pmol/g) were found in three adult females indicating that they were pregnant or ovulating. High androgen concentrations in two of the males reflected that one was adult and that one (possibly) had reached puberty. In males a significant positive and strong correlation between body length and testosterone (TS) levels was identified. Furthermore, positive and significant correlations were found between 4-OH-CB107/4'-OH-CB108 and 17β-estradiol in males. In adult females significant positive correlations were identified between PRE and CB149 and t-nonachlor, between estrone and CB138, -149, -187 and p,p'-DDE, between androstenedione and CB187, and between TS and CB-99 and -153. Although relationships between the POPs and the steroid hormones reported herein are not evidence of cause-effect relationships, the positive correlations between steroids and POPs, particularly in females, suggest that POPs may have some endocrine disrupting effects on the steroid homeostasis in this species.
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Affiliation(s)
- Katrin S Hoydal
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway; Environment Agency, Traðagøta 38, P.O. BOX 2048, FO-165 Argir, Faroe Islands.
| | - Bjarne Styrishave
- Toxicology Laboratory, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2100 OE, Denmark
| | - Tomasz M Ciesielski
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, 1125 Colonel By Dr. (Raven Road), Ottawa, Canada K1A 0H3
| | - Maria Dam
- Environment Agency, Traðagøta 38, P.O. BOX 2048, FO-165 Argir, Faroe Islands
| | - Bjørn M Jenssen
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
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15
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Melnes M, Gabrielsen GW, Herzke D, Sagerup K, Jenssen BM. Dissimilar effects of organohalogenated compounds on thyroid hormones in glaucous gulls. ENVIRONMENTAL RESEARCH 2017; 158:350-357. [PMID: 28683408 DOI: 10.1016/j.envres.2017.06.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/09/2017] [Accepted: 06/12/2017] [Indexed: 06/07/2023]
Abstract
The glaucous gull (Larus hyperboreus) is an arctic top predator and scavenger exposed to high levels of mixtures of organohalogenated contaminants (OHCs) of which many interfere with the thyroid hormone (TH) system. In the present study, we applied statistical modeling to investigate the potential combined influence of the mixture of chlorinated, brominated and perfluorinated organic compounds in plasma of glaucous gulls on their plasma TH concentrations. In females, there were significant negative associations between several organochlorinated compounds (OCs) and free thyroxin (FT4) and triiodothyronine (FT3), indicating additive negative effects on FT4 and FT3. However, in these females there was also a significant positive association between perfluorooctane sulfonate (PFOS) and FT3. The inverse associations between several OCs and FT3 and the contrasting positive association between PFOS and FT3, indicate that these two groups of OHCs may have dissimilar and antagonistic effects on FT3 in female glaucous gulls. In males, there were no associations between any of the OHCs and the THs. That OHCs affect THs in a complex manner involving both additive and antagonistic effects add to the challenge of interpreting the overall functional effect of thyroid disruptive chemicals in wildlife. However, experimental studies are needed to confirm or disprove such effects.
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Affiliation(s)
- Marte Melnes
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | | | - Dorte Herzke
- Norwegian Institute for Air Research, Fram Centre, NO-9296 Tromsø, Norway
| | | | - Bjørn Munro Jenssen
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; Department of Arctic Technology, University Centre in Svalbard, NO 9171 Longyearbyen, Norway.
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16
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Bourgeon S, Riemer AK, Tartu S, Aars J, Polder A, Jenssen BM, Routti H. Potentiation of ecological factors on the disruption of thyroid hormones by organo-halogenated contaminants in female polar bears (Ursus maritimus) from the Barents Sea. ENVIRONMENTAL RESEARCH 2017; 158:94-104. [PMID: 28614731 DOI: 10.1016/j.envres.2017.05.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/28/2017] [Accepted: 05/28/2017] [Indexed: 06/07/2023]
Abstract
As apex predators, polar bears (Ursus maritimus) are among the most heavily polluted organisms in the Arctic. In addition to this anthropogenic stressor, climate warming has been shown to negatively affect their body condition, reproductive output and survival. Among potential underlying physiological mechanisms, thyroid hormones (THs), which control thermoregulation, metabolism and reproduction, can be affected by a variety of both natural and anthropogenic factors. While THs have been extensively used as proxies for pollution exposure in mammals, including polar bears, there is a lack of knowledge of their natural variations. In this context, we examined seasonal variations in body condition and circulating TH concentrations in free-ranging female polar bears. Females with variable reproductive status (i.e., solitary, with cubs of the year or with yearlings) were sampled from locations with contrasted sea ice conditions. Furthermore, we studied THs in relation to levels of organo-halogenated contaminants. As predicted, solitary females were in better condition than females caring for offspring, especially in spring. In addition, TH levels were lower in autumn compared to spring, although this seasonal effect was mainly observed in solitary females. Finally, the negative relationships between organochlorine and perfluoroalkyl substances and some THs suggest a possible alteration of homeostasis of THs. Since the latter relationships were only observed during spring, we emphasize the importance of considering the ecological factors when using THs as proxies for pollution exposure. Yet, the combined effects of natural and anthropogenic stressors on THs might impair the ability of polar bears to adapt to ongoing climate changes.
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Affiliation(s)
- Sophie Bourgeon
- The Arctic University of Norway, UiT, Department of Arctic and Marine Biology, Tromsø, Norway; Norwegian Polar Institute, Fram Centre, Tromsø, Norway.
| | - Astrid Kolind Riemer
- Norwegian University of Science and Technology, NTNU, Department of Biology, Trondheim, Norway.
| | - Sabrina Tartu
- Norwegian Polar Institute, Fram Centre, Tromsø, Norway.
| | - Jon Aars
- Norwegian Polar Institute, Fram Centre, Tromsø, Norway.
| | - Anuschka Polder
- Norwegian University of Life Science, NMBU, Campus Adamstua, Oslo, Norway.
| | - Bjørn Munro Jenssen
- Norwegian University of Science and Technology, NTNU, Department of Biology, Trondheim, Norway.
| | - Heli Routti
- Norwegian Polar Institute, Fram Centre, Tromsø, Norway.
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17
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Desforges JP, Eulaers I, Periard L, Sonne C, Dietz R, Letcher RJ. A rapid analytical method to quantify complex organohalogen contaminant mixtures in large samples of high lipid mammalian tissues. CHEMOSPHERE 2017; 176:243-248. [PMID: 28273531 DOI: 10.1016/j.chemosphere.2017.02.098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 02/12/2017] [Accepted: 02/19/2017] [Indexed: 06/06/2023]
Abstract
In vitro investigations of the health impact of individual chemical compounds have traditionally been used in risk assessments. However, humans and wildlife are exposed to a plethora of potentially harmful chemicals, including organohalogen contaminants (OHCs). An alternative exposure approach to individual or simple mixtures of synthetic OHCs is to isolate the complex mixture present in free-ranging wildlife, often non-destructively sampled from lipid rich adipose. High concentration stock volumes required for in vitro investigations do, however, pose a great analytical challenge to extract sufficient amounts of complex OHC cocktails. Here we describe a novel method to easily, rapidly and efficiently extract an environmentally accumulated and therefore relevant contaminant cocktail from large (10-50 g) marine mammal blubber samples. We demonstrate that lipid freeze-filtration with acetonitrile removes up to 97% of blubber lipids, with minimal effect on the efficiency of OHC recovery. Sample extracts after freeze-filtration were further processed to remove residual trace lipids via high-pressure gel permeation chromatography and solid phase extraction. Average recoveries of OHCs from triplicate analysis of killer whale (Orcinus orca), polar bear (Ursus maritimus) and pilot whale (Globicephala spp.) blubber standard reference material (NIST SRM-1945) ranged from 68 to 80%, 54-92% and 58-145%, respectively, for 13C-enriched internal standards of six polychlorinated biphenyl congeners, 16 organochlorine pesticides and four brominated flame retardants. This approach to rapidly generate OHC mixtures shows great potential for experimental exposures using complex contaminant mixtures, research or monitoring driven contaminant quantification in biological samples, as well as the untargeted identification of emerging contaminants.
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Affiliation(s)
- Jean-Pierre Desforges
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000, Roskilde, Denmark
| | - Igor Eulaers
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000, Roskilde, Denmark
| | - Luke Periard
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON, K1A 0H3, Canada
| | - Christian Sonne
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000, Roskilde, Denmark
| | - Rune Dietz
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000, Roskilde, Denmark
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON, K1A 0H3, Canada.
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Sonne C, Torjesen PA, Fuglei E, Muir DCG, Jenssen BM, Jørgensen EH, Dietz R, Ahlstrøm Ø. Exposure to Persistent Organic Pollutants Reduces Testosterone Concentrations and Affects Sperm Viability and Morphology during the Mating Peak Period in a Controlled Experiment on Farmed Arctic Foxes (Vulpes lagopus). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:4673-4680. [PMID: 28301147 DOI: 10.1021/acs.est.7b00289] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We investigated testosterone production and semen parameters in farmed Arctic foxes by dietary exposure to persistent organic pollutants (POPs) for 22 months. Eight male foxes were given a diet of POP-contaminated minke whale blubber, whereas their eight male siblings were fed a control diet containing pig fat as the main fat source. The minke whale-based feed contained a ∑POPs concentration of 802 ng/g ww, whereas the pig-based feed contained ∑POPs of 24 ng/g ww. At the end of the experiment, ∑POP concentrations in adipose tissue were 8856 ± 2535 ng/g ww in the exposed foxes and 1264 ± 539 ng/g ww in the control foxes. The exposed group had 45-64% significantly lower testosterone concentrations during their peak mating season compared to the controls (p ≤ 0.05), while the number of dead and defect sperm cells was 27% (p = 0.07) and 15% (p = 0.33) higher in the exposed group. Similar effects during the mating season in wild Arctic foxes may affect mating behavior and reproductive success. On the basis of these results, we recommend testosterone as a sensitive biomarker of POP exposure and that seasonal patterns are investigated when interpreting putative endocrine disruption in Arctic wildlife with potential population-level effects.
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Affiliation(s)
- Christian Sonne
- Department of Bioscience, Arctic Research Centre (ARC), Aarhus University, Faculty of Science and Technology , Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark
| | - Peter A Torjesen
- Department of Endocrinology, Hormone Laboratory , Oslo University Hospital, NO-0514 Oslo, Norway
| | - Eva Fuglei
- Norwegian Polar Institute , Fram Centre, NO-9296 Tromsø, Norway
| | - Derek C G Muir
- Aquatic Contaminants Research Division, Environment and Climate Change Canada , Burlington, Ontario, Canada L7S 1A1
| | - Bjørn Munro Jenssen
- Department of Bioscience, Arctic Research Centre (ARC), Aarhus University, Faculty of Science and Technology , Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark
- Department of Biology, Norwegian University of Science and Technology , NO-7491 Trondheim, Norway
- Department of Arctic Technology, The University Centre in Svarbard , P.O. Box 156, NO-9171 Longyearbyen, Norway
| | - Even H Jørgensen
- Department of Arctic and Marine Biology, UiT the Arctic University of Norway , NO-9037 Tromsø, Norway
| | - Rune Dietz
- Department of Bioscience, Arctic Research Centre (ARC), Aarhus University, Faculty of Science and Technology , Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark
| | - Øystein Ahlstrøm
- Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences , NO-1433 Ås, Norway
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Rogstad TW, Sonne C, Villanger GD, Ahlstøm Ø, Fuglei E, Muir DCG, Jørgensen E, Jenssen BM. Concentrations of vitamin A, E, thyroid and testosterone hormones in blood plasma and tissues from emaciated adult male Arctic foxes (Vulpes lagopus) dietary exposed to persistent organic pollutants (POPs). ENVIRONMENTAL RESEARCH 2017; 154:284-290. [PMID: 28119248 DOI: 10.1016/j.envres.2017.01.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 06/06/2023]
Abstract
The aim of the present study was to investigate the relationships and effects of oral POP exposure on retinol (vitamin A), α-tocopherol (vitamin E), thyroid hormones and testosterone in emaciated adult farmed Arctic foxes. Eight brother-pairs were exposed to either a diet containing naturally POP-contaminated minke whale blubber (Balaenoptera acutorostrata) (n=8), or a control diet containing pig (Sus scrofa) fat as the primary fat source (n=8) for 22 months. In the whale blubber containing feed the ∑POPs concentration was 802ng/g w.w. and it was 24ng/g w.w. in control feed. The liver mass was significantly higher and the ratio of FT4 (free thyroxine):FT3 (free triiodothyronine) was significantly lower in the POP exposed group as compared to the control group given feed with pig fat (both p<0.05). The exposed group revealed lower plasma and liver concentrations of α-tocopherol compared to the control group (both p<0.05). These results indicate that plasma FT4:FT3 ratio and plasma and liver α-tocopherol are valuable biomarker endpoints for chronic oral POP exposure in wild Arctic foxes. Based on this we suggest that plasma FT4:FT3 ratio and plasma and liver α-tocopherol are valuable biomarker endpoints for chronic POP exposure in wildlife Arctic foxes and that these perturbations may affect their health status.
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Affiliation(s)
- Tonje W Rogstad
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Christian Sonne
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark.
| | - Gro D Villanger
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; Mental and Physical Health, Department of Child Health, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, 0473 Oslo, Norway
| | - Øystein Ahlstøm
- Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, N-1432 Ås, Norway
| | - Eva Fuglei
- Norwegian Polar Institute, FRAM Centre, NO-9296 Tromsø, Norway
| | - Derek C G Muir
- National Water Research Institute, Environment Canada, Burlington, Ontario, Canada L7R 4A6
| | - Even Jørgensen
- Department of Arctic and Marine Biology, UiT the Arctic University of Norway, N-9037 Tromsø, Norway
| | - Bjørn Munro Jenssen
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
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Pedersen KE, Letcher RJ, Sonne C, Dietz R, Styrishave B. Per- and polyfluoroalkyl substances (PFASs) - New endocrine disruptors in polar bears (Ursus maritimus)? ENVIRONMENT INTERNATIONAL 2016; 96:180-189. [PMID: 27692342 DOI: 10.1016/j.envint.2016.07.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 06/06/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are emerging in the Arctic and accumulate in brain tissues of East Greenland (EG) polar bears. In vitro studies have shown that PFASs might possess endocrine disrupting abilities and therefore the present study was conducted to investigate potential PFAS induced alterations in brain steroid concentrations. The concentrations of eleven steroid hormones were determined in eight brain regions from ten EG polar bears. Pregnenolone (PRE), the dominant progestagen, was found in mean concentrations of 5-47ng/g (ww) depending on brain region. PRE showed significantly (p<0.01) higher concentrations in female compared to male bears. Dehydroepiandrosterone (DHEA) found in mean concentrations 0.67-4.58ng/g (ww) was the androgen found in highest concentrations. Among the estrogens estrone (E1) showed mean concentrations of 0.90-2.21ng/g (ww) and was the most abundant. Remaining steroid hormones were generally present in concentrations below 2ng/g (ww). Steroid levels in brain tissue could not be explained by steroid levels in plasma. There was however a trend towards increasing estrogen levels in plasma resulting in increasing levels of androgens in brain tissue. Correlative analyses showed positive associations between PFASs and 17α-hydroxypregnenolone (OH-PRE) (e.g. perflouroalkyl sulfonates (∑PFSA): p<0.01, r=0.39; perfluoroalkyl carboxylates (∑PFCA): p<0.01, r=0.61) and PFCA and testosterone (TS) (∑PFCA: p=0.03, r=0.30) across brain regions. Further when investigating correlative associations in specific brain regions significant positive correlations were found between ∑PFCA and several steroid hormones in the occipital lobe. Correlative positive associations between PFCAs and steroids were especially observed for PRE, progesterone (PRO), OH-PRE, DHEA, androstenedione (AN) and testosterone (TS) (all p≤0.01, r≥0.7). The results from the present study generally indicate that an increase in PFASs concentration seems to concur with an increase in steroid hormones of EG polar bears. It is, however, not possible to determine whether alterations in brain steroid concentrations arise from interference with de novo steroid synthesis or via disruption of peripheral steroidogenic tissues mainly in gonads and feedback mechanisms. Steroids are important for brain plasticity and gender specific behavior as well as postnatal development and sexually dimorph brain function. The present work indicates an urgent need for a better mechanistic understanding of how PFASs may affect the endocrine system of polar bears and potentially other mammal species.
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Affiliation(s)
- Kathrine Eggers Pedersen
- Toxicology Laboratory, Section of Advanced Drug Analysis, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
| | - Robert J Letcher
- Wildlife and Landscape Science Directorate, Science and Technology Branch, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3, Canada
| | - Christian Sonne
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre, P.O. Box 358, Roskilde DK-4000, Denmark
| | - Rune Dietz
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre, P.O. Box 358, Roskilde DK-4000, Denmark
| | - Bjarne Styrishave
- Toxicology Laboratory, Section of Advanced Drug Analysis, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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Gaum PM, Lang J, Esser A, Schettgen T, Neulen J, Kraus T, Gube M. Exposure to polychlorinated biphenyls and the thyroid gland - examining and discussing possible longitudinal health effects in humans. ENVIRONMENTAL RESEARCH 2016; 148:112-121. [PMID: 27038832 DOI: 10.1016/j.envres.2016.03.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/17/2016] [Accepted: 03/15/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Many previous studies have dealt with the effect of polychlorinated biphenyls (PCBs) on the thyroid gland, but their findings are inconsistent. One problem of these studies has been their use of cross-sectional designs. OBJECTIVES The aim of the current study is to investigate longitudinal effects of PCBs on the thyroid gland, focusing on: morphological changes in thyroid tissue (i.e. thyroid volume), changes in thyroid hormones and in thyroid antibodies. METHODS A total of 122 individuals (Mage=44.7) were examined over a period of four years (t(1) until t(4)). Medical history was collected via interviews, an ultrasound examination was performed and blood samples were taken to determine plasma PCB levels, thyroid stimulating hormone (TSH), free triiodthyronine (fT3), free thyroxine (fT4), thyroid peroxidase antibodies (TPOab), thyreoglobulin antibodies (TGab) and thyroid-stimulating hormone receptor antibodies (TSHRab). Rank correlation coefficients and mixed effect models were performed controlling for age and total lipids. RESULTS There were negative correlations between higher chlorinated biphenyls and fT3, cross-sectionally as well as longitudinally. We also found an interaction effect of higher-chlorinated PCBs over time for fT4 as well as TSHRab. In case of high exposure, a decrease in fT4 and an increase in TSHRab level were found over time. In regards to the other variables, our findings yielded no clear results in the examined time period. CONCLUSION This is the first study to shows a PCB-related effect on fT3, fT4 and TSHRab over a four year period. The data also suggest that morphological and antibody findings remain inconsistent and do not allow for unambiguous interpretation.
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Affiliation(s)
- Petra M Gaum
- Institute for Occupational and Social Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany.
| | - Jessica Lang
- Institute for Occupational and Social Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany
| | - André Esser
- Institute for Occupational and Social Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany
| | - Thomas Schettgen
- Institute for Occupational and Social Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany
| | - Joseph Neulen
- Clinic for Gynaecological Endocrinology and Reproductive Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany
| | - Thomas Kraus
- Institute for Occupational and Social Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany
| | - Monika Gube
- Institute for Occupational and Social Medicine, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany
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22
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Hoydal KS, Ciesielski TM, Borrell A, Wasik A, Letcher RJ, Dam M, Jenssen BM. Relationships between concentrations of selected organohalogen contaminants and thyroid hormones and vitamins A, E and D in Faroese pilot whales. ENVIRONMENTAL RESEARCH 2016; 148:386-400. [PMID: 27131793 DOI: 10.1016/j.envres.2016.04.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 04/02/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
Pilot whales (Globicephala melas) from the Faroe Islands, North-East Atlantic, have high body concentrations of organohalogenated compounds (OHCs), such as polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (BFRs). The aim of the present study was to examine if and to what extent blood plasma and liver concentrations of several groups of these OHCs are related to concentrations of relevant nutritional and hormonal biomarkers in pilot whales. Thyroid hormones (THs: total and free thyroxine and total and free triiodothyronine) and vitamin A (retinol), D (25-hydroxyvitamin D3) and E (α-tocopherol) were analysed in plasma (n=27) and vitamin A (total vitamin A, retinol and retinyl palmitate) and E (α- and γ-tocopherol) were analysed in liver (n=37) of Faroe Island pilot whales. Correlative relationships between the biomarkers and OHC concentrations previously analysed in the same tissues in these individuals were studied. The TH concentrations in plasma were significantly higher in juveniles than in adults. Vitamin D concentrations in plasma and α- and γ-tocopherol in liver were higher in adults than in juveniles. Multivariate statistical modelling showed that the age and sex influenced the relationship between biomarkers and OHCs. Some significant positive relationships were found between OHCs and thyroid hormone concentrations in the youngest juveniles (p<0.05). In plasma of juvenile whales α-tocopherol was also positively correlated with all the OHCs (p<0.05). Only few significant correlations were found between single OHCs and retinol and vitamin D in plasma within the age groups. There were significant negative relationships between hepatic PBDE concentrations and retinol (BDE-47) and γ-tocopherol (BDE-49, -47, -100, -99, -153) in liver. The relationships between OHCs and THs or vitamins suggest that in pilot whales OHCs seem to have minor effects on TH and vitamin concentrations.
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Affiliation(s)
- Katrin S Hoydal
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway; Environment Agency, Traðagøta 38, FO-165 Argir, Faroe Islands.
| | - Tomasz M Ciesielski
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Asunción Borrell
- Department of Animal Biology and Biodiversity Research Institute (IRBio), University of Barcelona, Spain
| | - Andrzej Wasik
- Gdańsk University of Technology, Chemical Faculty, Department of Analytical Chemistry, G. Narutowicza 11/12 St., 80-233 Gdańsk, Poland
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, 1125 Colonel By Dr. (Raven Road), Ottawa K1A 0H3, Canada
| | - Maria Dam
- Environment Agency, Traðagøta 38, FO-165 Argir, Faroe Islands
| | - Bjørn M Jenssen
- Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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23
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Lennert AE. What happens when the ice melts? Belugas, contaminants, ecosystems and human communities in the complexity of global change. MARINE POLLUTION BULLETIN 2016; 107:7-14. [PMID: 27062887 DOI: 10.1016/j.marpolbul.2016.03.050] [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: 11/18/2015] [Revised: 03/07/2016] [Accepted: 03/21/2016] [Indexed: 06/05/2023]
Abstract
In general, it is important to examine the whole spectrum of interrelated fields while comprehending pollution, climate change or the environment, because some of their relevances are expected and others not. This study aims at comparatively examining different but interrelated ways of acquiring and communicating information on environmental changes, focusing on pollution in the Arctic, in particular Greenland. In the context of climate change, it discusses how heavily polluted and stressed Arctic marine ecosystems may be affected when ice melts. Bridging cultures of knowledge, this study claims that traditional knowledge together with natural science and studies of contaminants in Arctic marine ecosystems can indicate behavioural factors, elements acting as additional stressors on animals and communities relying on them. Furthermore, it explains the role of scientific engagement with local communities in not only the identification and verification of stressors, enhancing our understanding of them, but also the proposal of solutions to related problems.
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Affiliation(s)
- Ann Eileen Lennert
- Greenland Institute of Natural Resources and Climate Research Center, Nuuk, Greenland; Ilisimatusarfik, University of Greenland, Manutoq 1, 3905 Nuussuaq, Greenland; Department of Arctic and Marine Biology, University of Tromsø, Tromsø 9012, Norway
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24
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Zhang Q, Ji C, Yin X, Yan L, Lu M, Zhao M. Thyroid hormone-disrupting activity and ecological risk assessment of phosphorus-containing flame retardants by in vitro, in vivo and in silico approaches. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 210:27-33. [PMID: 26701863 DOI: 10.1016/j.envpol.2015.11.051] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Revised: 11/27/2015] [Accepted: 11/27/2015] [Indexed: 05/03/2023]
Abstract
In recent years, phosphorus-containing flame retardants (PFRs) have been frequently detected in various environmental media and biota - and in humans - as the result of steady increase in global usage of PFRs. However, studies on the potential health and ecological risks of PFRs are still scarce. In this study, we investigated the thyroid hormone-disrupting activity and ecological risk of nine frequently detected PFRs by in vitro, in vivo and in silico approaches. Results from the dual-luciferase reporter gene assay showed that tributyl phosphate (TNBP), tricresyl phosphate (TMPP), tris(2-chloroisopropyl)phosphate (TCIPP) and tris(2-chloro-1-(chloromethyl)ethyl)phosphate (TDCIPP) exerted thyroid receptor β (TRβ) antagonistic activity, with the values of RIC20 of 5.2 × 10(-7), 2.7 × 10(-7), 1.2 × 10(-6) and 6.8 × 10(-6) M, respectively. Molecular docking platform simulations suggested that the observed effects may be attributed to direct binding of PFRs to TR. Results from the T-screen assay indicated that TNBP and TMPP showed T3 antagonistic activity and thus significantly decreased the viability of GH3 cell lines in the presence of T3. The exposure assay using Xenopus tropicalis embryos revealed the potential teratogenic effect of TNBP, TMPP, TCIPP and TDCIPP. In conclusion, our studies revealed that some PFRs were potential thyroid hormone disruptors and may cause health and ecological risks. However, the mode of action of PFRs on TR remains uncertain. The correlation between the predicted affinity and the amplitude of the effect observed in cell based assay is encouraging, but not decisive. Further in vitro binding experiments of TR and PFRs are required. At the same time, the results provided here also demonstrated that multi-model approaches are of great importance to comprehensively evaluate the potential risks of emerging contaminants.
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Affiliation(s)
- Quan Zhang
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Chenyang Ji
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Xiaohui Yin
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China; School of Agricultural and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou 311300, China
| | - Lu Yan
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Meiya Lu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Meirong Zhao
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
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Guo W, Gardner S, Yen S, Petreas M, Park JS. Temporal Changes of PBDE Levels in California House Cats and a Link to Cat Hyperthyroidism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:1510-1518. [PMID: 26699103 DOI: 10.1021/acs.est.5b04252] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this study, we measured serum PBDE levels in California (CA) house cats during two time periods: 2008-2010 and 2012-2013 to assess the impacts of the decline in use of these materials after the bans. The median ∑19PBDE level in CA household cats (age ≥10 yr) was 3479 ng/g lipid in 2008-2010 (1st time period, n = 21) and 1518 ng/g lipid in 2012-2013 (2nd time period, n = 22), about 2 times lower than in the first time period (p = 0.006). In contrast, PCB and OCP levels showed no statistically significant changes. With better matched group size and age (HT = 11 vs non-HT = 11, age ≥10 yr) in the second time period, we found that ∑19PBDE level (mean ± SE ng/g lipid) was significantly higher in the HT group (3906 ± 1442) than those in the non-HT group (1125 ± 244) (p = 0.0030). Higher levels of PCBs and OCPs were also found in HT group. Despite the declines of PBDE levels, our findings indicate that the current levels of PBDEs, as well as PCBs and OCPs, may still pose health effects for house cats and, possibly, humans.
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Affiliation(s)
- Weihong Guo
- California Department of Toxic Substances Control, California Environmental Protection Agency , 700 Heinz Avenue, Berkeley, California 94710, United States
| | - Stephen Gardner
- VCA Albany Animal Hospital , 1550 Solano Avenue, Albany, California 94707, United States
| | - Simon Yen
- Campus Veterinary Clinic , 1807 M.L.K. Jr Way, Berkeley, California 94709, United States
| | - Myrto Petreas
- California Department of Toxic Substances Control, California Environmental Protection Agency , 700 Heinz Avenue, Berkeley, California 94710, United States
| | - June-Soo Park
- California Department of Toxic Substances Control, California Environmental Protection Agency , 700 Heinz Avenue, Berkeley, California 94710, United States
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26
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Letcher RJ, Lu Z, de Solla SR, Sandau CD, Fernie KJ. Snapping Turtles (Chelydra serpentina) from Canadian Areas of Concern across the southern Laurentian Great Lakes: Chlorinated and brominated hydrocarbon contaminants and metabolites in relation to circulating concentrations of thyroxine and vitamin A. ENVIRONMENTAL RESEARCH 2015; 143:266-278. [PMID: 26519832 DOI: 10.1016/j.envres.2015.10.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 09/16/2015] [Accepted: 10/14/2015] [Indexed: 06/05/2023]
Abstract
The metabolites of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), as well as other halogenated phenolic contaminants (HPCs) have been shown to have endocrine-disrupting properties, and have been reported with increasing frequency in the blood of wildlife, and mainly in mammals and birds. However, little is known about the persistence, accumulation and distribution of these contaminants in long-lived freshwater reptiles. In the present study, in addition to a large suite of chlorinated and brominated contaminants, metabolites and HPCs, we assessed and compared hydroxylated (OH) PCBs and OH-PBDEs relative to PCBs and PBDEs, respectively, in the plasma of adult male common snapping turtles (Chelydra serpentina). Blood samples were collected from 62 snapping turtles (2001-2004) at 12 wetland sites between the Detroit River and the St. Lawrence River on the Canadian side of the Laurentian Great Lakes of North America. Turtles were sampled from sites designated as Areas of Concern (AOCs) and from a relatively clean reference site in southern Georgian Bay (Tiny Marsh), Lake Huron. Plasma concentrations of Σ46PCB (10-340 ng/g wet weight (ww)) and Σ28OH-PCB (3-83 ng/g ww) were significantly greater (p<0.05) in turtles from the Turkey Creek and Muddy Creek-Wheatley Harbour sites in Lake Erie compared with the reference site turtles. The HPC, pentachlorophenol (PCP), had a mean concentration of 9.6±1.1 ng/g ww. Of the 28 OH-CB congeners screened for, 4-OH-CB187 (42±7 ng/g ww) was the most concentrated of all HPCs measured. Of the 14 OH-BDE congeners examined, four (4'-OH-BDE17, 3-OH-BDE47, 5-OH-BDE47 and 4'-OH-BDE49) were consistently found in all plasma samples. p,p'-DDE was the most concentrated of the 18 organochlorine pesticides (OCPs) examined. The mean concentrations of circulating total thyroxine (TT4), dehydroretinol and retinol in the plasma of the male snapping turtles regardless of sampling site were 5.4±0.3, 81±4.7 and 291±13 ng/mL, respectively. Significant (p<0.05) negative (e.g. cis-chlordane) or positive (e.g. BDE-99) correlations between some of the target contaminants and TT4, dehydroretinol or retinol were observed. To our knowledge, we report for the first time on HPC (e.g. OH-PCBs) and methylsulfonyl- (MeSO2-) PCB metabolite contaminants in the plasma of any freshwater turtle or freshwater reptilian species. Our findings also show that the accumulation of OH-PCBs, MeSO2-PCBs, OH-PBDEs and some OCPs in the snapping turtles from Lake Erie and Lake Ontario (in 2001-2004) had the potential for eliciting endocrine disruption. Exposure to these contaminants and associated adverse effects on the endocrine system in freshwater reptiles and the related mechanisms require further investigation.
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Affiliation(s)
- Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Ontario, Canada K1A 0H3.
| | - Zhe Lu
- Richardson College for the Environment, Environmental Studies Program and Department of Chemistry, University of Winnipeg, Winnipeg, MB, Canada R3B 2E9
| | - Shane R de Solla
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, Canada Centre for Inland Waters, Burlington, Ontario, Canada L7S 1A1
| | | | - Kimberly J Fernie
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, Canada Centre for Inland Waters, Burlington, Ontario, Canada L7S 1A1
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27
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Dietz R, Gustavson K, Sonne C, Desforges JP, Rigét FF, Pavlova V, McKinney MA, Letcher RJ. Physiologically-based pharmacokinetic modelling of immune, reproductive and carcinogenic effects from contaminant exposure in polar bears (Ursus maritimus) across the Arctic. ENVIRONMENTAL RESEARCH 2015; 140:45-55. [PMID: 25825130 DOI: 10.1016/j.envres.2015.03.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 03/13/2015] [Accepted: 03/14/2015] [Indexed: 06/04/2023]
Abstract
Polar bears (Ursus maritimus) consume large quantities of seal blubber and other high trophic marine mammals and consequently have some of the highest tissue concentrations of organohalogen contaminants (OHCs) among Arctic biota. In the present paper we carried out a risk quotient (RQ) evaluation on OHC-exposed polar bears harvested from 1999 to 2008 and from 11 circumpolar subpopulations spanning from Alaska to Svalbard in order to evaluate the risk of OHC-mediated reproductive effects (embryotoxicity, teratogenicity), immunotoxicity and carcinogenicity (genotoxicity). This RQ evaluation was based on the Critical Body Residue (CBR) concept and a Physiologically-Based Pharmacokinetic Modelling (PBPK) approach using OHC concentrations measured in polar bear adipose or liver tissue. The range of OHC concentrations within polar bear populations were as follows for adipose, sum polychlorinated biphenyls ∑PCBs (1797-10,537 ng/g lw), sum methylsulphone-PCB ∑MeSO2-PCBs (110-672 ng/g lw), sum chlordanes ∑CHLs (765-3477 ng/g lw), α-hexachlorocyclohexane α-HCH (8.5-91.3 ng/g lw), β-hexachlorocyclohexane β-HCH (65.5-542 ng/g lw), sum chlorbenzenes ∑ClBzs (145-304 ng/g lw), dichlorodiphenyltrichloroethane ∑DDTs (31.5-206 ng/g lw), dieldrin (69-249 ng/g lw), polybrominated diphenyl ethers ∑PBDEs (4.6-78.4 ng/g lw). For liver, the perfluorooctanesulfonic acid (PFOS) concentrations ranged from 231-2792 ng/g ww. The total additive RQ from all OHCs ranged from 4.3 in Alaska to 28.6 in East Greenland bears for effects on reproduction, immune health and carcinogenicity, highlighting the important result that the toxic effect threshold (i.e. RQ>1) was exceeded for all polar bear populations assessed. PCBs were the main contributors for all three effect categories, contributing from 70.6% to 94.3% of the total risk and a RQ between 3.8-22.5. ∑MeSO2-PCBs were the second highest effect contributor for reproductive and immunological effects (0.17<RQ<1.4), whereas PFOS was the second highest effect contributor for carcinogenic (genotoxic) effects (0.35<RQ<2.5). The results from this study corroborate and lend further support to previous assessments of the possible adverse health effects of exposure to known and measured OHCs in polar bears. We therefore suggest that Critical Daily Doses (CDD) should be investigated in "ex vivo" dose-response studies on polar bears to replace laboratory studies on rats (Rattus rattus) to reveal whether high RQs are maintained.
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Affiliation(s)
- Rune Dietz
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark.
| | - Kim Gustavson
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark.
| | - Christian Sonne
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark.
| | - Jean-Pierre Desforges
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark.
| | - Frank F Rigét
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark.
| | - Viola Pavlova
- Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Melissa A McKinney
- Department of Natural Resources and the Environment, University of Connecticut, Storrs, CT 06269, USA; Center for Environmental Sciences and Engineering, University of Connecticut, Storrs, CT 06269, USA.
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON, Canada K1A 0H3.
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Hoydal KS, Letcher RJ, Blair DAD, Dam M, Lockyer C, Jenssen BM. Legacy and emerging organic pollutants in liver and plasma of long-finned pilot whales (Globicephala melas) from waters surrounding the Faroe Islands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 520:270-285. [PMID: 25817764 DOI: 10.1016/j.scitotenv.2015.03.056] [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] [Received: 01/21/2015] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 06/04/2023]
Abstract
Concentrations of PCBs, organochlorine pesticides (OCPs), brominated flame retardants and a suite of relevant metabolites of these POPs, in all 175 different compounds, were determined in liver and plasma of traditionally hunted pilot whales (n=14 males and n=13 females of different age groups) from the Faroe Islands. The main objectives of this study were to determine differences in the presence and concentrations of the compounds in the liver and plasma, how they depend on developmental stage (calves, sub adults, and adult females), and to assess maternal transfer of the compounds to suckling calves. Generally, the lipid weight (lw) concentrations of quantified POPs in the liver and plasma of pilot whales were positively correlated, and lw concentrations of most POPs did not differ between these matrices. However, concentrations of some individual POPs differed significantly (p<0.05) between plasma and liver; CB-153 (p=0.044), CB-174 (p=0.027) and BDE-47 (p=0.017) were higher in plasma than in liver, whereas p,p'-DDE (p=0.004) and HCB (p<0.001) were higher in liver than in plasma. POP concentrations differed between age/gender groups with lower levels in adult females than in juveniles. The relative distribution of compounds also differed between the age groups, due to the influence of the maternal transfer of the compounds. The results indicated that larger, more hydrophobic POPs were transferred to the offspring less efficiently than smaller or less lipid soluble compounds. Very low levels of both OH- and/or MeSO2-PCB and PBDE metabolites were found in all age groups, with no significant (p>0.05) differences between the groups, strongly suggesting a very low metabolic capacity for their formation in pilot whales. The lack of difference in the metabolite concentrations between the age groups also indicates less maternal transfer of these contaminant groups compared to the precursor compounds.
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Affiliation(s)
- Katrin S Hoydal
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway; Environment Agency, Traðagøta 38, P.O. BOX 2048, FO-165 Argir, Faroe Islands.
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Environment Canada, National Wildlife Research Centre, 1125 Colonel By Dr. (Raven Road), Carleton University, Ottawa K1A 0H3, Canada
| | - David A D Blair
- Ecotoxicology and Wildlife Health Division, Environment Canada, National Wildlife Research Centre, 1125 Colonel By Dr. (Raven Road), Carleton University, Ottawa K1A 0H3, Canada
| | - Maria Dam
- Environment Agency, Traðagøta 38, P.O. BOX 2048, FO-165 Argir, Faroe Islands
| | | | - Bjørn M Jenssen
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
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Jenssen BM, Villanger GD, Gabrielsen KM, Bytingsvik J, Bechshoft T, Ciesielski TM, Sonne C, Dietz R. Anthropogenic flank attack on polar bears: interacting consequences of climate warming and pollutant exposure. Front Ecol Evol 2015. [DOI: 10.3389/fevo.2015.00016] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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