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Fernie KJ, Karouna-Renier NK, Letcher RJ, Schultz SL, Peters LE, Palace V, Henry PFP. Endocrine and physiological responses of hatchling American kestrels (Falco sparverius) following embryonic exposure to technical short-chain chlorinated paraffins (C 10-13). Environ Int 2020; 145:106087. [PMID: 32950788 DOI: 10.1016/j.envint.2020.106087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 08/03/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
Short chain chlorinated paraffins (SCCPs) are complex mixtures of polychlorinated n-alkanes, shown to bioaccumulate but with unknown effects in wild birds. The present study examined development-related effects of SCCPs on captive American kestrels (Falco sparverius) treated in ovo on embryonic day (ED) 5 by injection with technical Chloroparaffin® (C10-13, 55.5% Cl) at environmentally relevant nominal (measured) concentrations of 10 (10), 50 (29) or 100 (97) ng ΣSCCP/g egg ww, and artificially incubated until hatching (ED27-ED29). The SCCP concentrations measured in the yolk sacs of the hatchling kestrels bracketed concentrations reported in the eggs of wild birds. Uptake and deposition of these SCCPs differed between male and female hatchlings, with only males showing differences in SCCP concentrations, being highest in the high-dose males than each of the other male groups. Embryonic exposure to SCCPs suppressed glandular total thyroxine (TT4) (20-33%) and reduced circulating triiodothyronine (TT3) (37-40%) in male hatchlings only when compared to control males, but had no effect on glandular TT3 or circulating TT4 in male or female kestrels. Histological assessments of thyroid glands showed that both sexes experienced significant structural changes indicative of gland activation. These thyroid glandular changes and the variations in SCCP concentrations were related to circulating TT3 in female hatchlings. Hepatic deiodinase enzyme (D1, D2) activities were stable and no SCCP-related changes were observed in hatching success, hatchling size, or immune organ size. However, several of the thyroid function indicators were correlated with hatchling size and smaller bursas and spleens, possibly indirectly through SCCP-induced changes in thyroid function. Because changes in thyroid function were evident at concentrations measured in wild bird eggs, similar changes may occur in wild nestlings. The potential impact of these changes on thyroid-mediated growth and survival in wild birds requires further investigation.
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Affiliation(s)
- K J Fernie
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment Canada, 867 Lakeshore Road, Burlington, ON L7S 1A1, Canada.
| | - N K Karouna-Renier
- USGS Patuxent Wildlife Research Center, BARC, East Bldg 308, 10300 Baltimore Avenue, Beltsville, MD 20705, USA
| | - R J Letcher
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment Canada, 1125 Colonel By Drive, Carleton University, Ottawa, ON K1A 0H3, Canada
| | - S L Schultz
- USGS Patuxent Wildlife Research Center, BARC, East Bldg 308, 10300 Baltimore Avenue, Beltsville, MD 20705, USA
| | - L E Peters
- Faculty of Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - V Palace
- International Institute of Sustainable Development - Experimental Lakes Area, Winnipeg, Manitoba R3B 0T4, Canada
| | - P F P Henry
- USGS Patuxent Wildlife Research Center, 12100 Beech Forest Road, Laurel, MD 20708, USA
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Guigueno MF, Head JA, Letcher RJ, Karouna-Renier N, Peters L, Hanas AM, Fernie KJ. Early life exposure to triphenyl phosphate: Effects on thyroid function, growth, and resting metabolic rate of Japanese quail (Coturnix japonica) chicks. Environ Pollut 2019; 253:899-908. [PMID: 31351298 DOI: 10.1016/j.envpol.2019.05.110] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/20/2019] [Accepted: 05/21/2019] [Indexed: 06/10/2023]
Abstract
Triphenyl phosphate (TPHP; CAS # 115-86-6), a commonly used plasticizer and flame retardant, has been reported in wild birds and identified as a potential high-risk chemical. We exposed Japanese quail (Coturnix japonica) by in ovo injection, and once hatched, orally each day for 5 days to safflower oil (controls) or TPHP dissolved in vehicle at low (5 ng TPHP/g), mid (50 ng TPHP/g), or high (100 ng TPHP/g) nominal TPHP doses. The low TPHP dose reflected concentrations in wild bird eggs, with mid and high doses 10x and 20x greater to reflect potential increases in environmental TPHP concentrations in the future. Despite no effects on mRNA expression in thyroid-related genes, TPHP exposure enhanced thyroid gland structure in high TPHP males, but in females, suppressed thyroid gland structure and activity (all TPHP females), and circulating free triiodothyronine (high TPHP females only). Consistent with thyroidal changes, and compared to controls, mid and high TPHP chicks experienced significantly reduced resting metabolic rate (≤13%) and growth (≤53%); mid TPHP males and high TPHP females were significantly smaller. The observed thyroidal effects and suppressed growth and metabolic rate of the quail chicks suggest that TPHP may adversely affect the health of wild birds.
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Affiliation(s)
- M F Guigueno
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Canada Centre for Inland Waters, Burlington, Ontario, L7S 1A1, Canada; Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada, H9X 3V9
| | - J A Head
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada, H9X 3V9
| | - R J Letcher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, Ontario, Canada
| | - N Karouna-Renier
- U.S. Geological Survey, Patuxent Wildlife Research Center, BARC East Bldg 308, 10300 Baltimore Avenue, Beltsville, MD, 20705, USA
| | - L Peters
- Riddell Faculty of Earth Environment and Resources, University of Manitoba, 125 Dysart Road, Winnipeg, Manitoba, R3T 2N2, Canada
| | - A M Hanas
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada, H9X 3V9
| | - K J Fernie
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Canada Centre for Inland Waters, Burlington, Ontario, L7S 1A1, Canada; Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada, H9X 3V9.
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Fernie KJ, Marteinson SC, Chen D, Palace V, Peters L, Soos C, Smits JEG. Changes in thyroid function of nestling tree swallows (Tachycineta bicolor) in relation to polycyclic aromatic compounds and other environmental stressors in the Athabasca Oil Sands Region. Environ Res 2019; 169:464-475. [PMID: 30530086 DOI: 10.1016/j.envres.2018.11.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/15/2018] [Accepted: 11/19/2018] [Indexed: 05/05/2023]
Abstract
In the Canadian Athabasca Oil Sands Region (AOSR), nestling tree swallows (Tachycineta bicolor) raised near mining-related activities accumulated greater concentrations of polycyclic aromatic compounds (PACs) that contributed to their poorer condition, growth, and reproductive success. Here, we report changes in thyroid function of the same 14 day old (do) nestlings (N ≤ 68) at these mining-related sites (OS1, OS2) compared to reference nestlings (REF1), and in relation to multiple environmental stressors that influence avian thyroid function. Thyroid function was compromised for OS1 nestlings but generally comparable between OS2 and REF1 chicks. In 2012, circulating total triiodothyronine (TT3) and thyroxine (TT4) were similar among all nestlings. The OS1 chicks had more active thyroid glands based on histological endpoints. Hepatic T4 outer-ring deiodinase (T4-ORD) activity was suppressed in OS1 and OS2 chicks. Despite inter-annual differences, OS1 chicks continued experiencing compromised thyroid function with significantly higher circulating TT4 and more active thyroid glands in 2013. The OS2 chicks had less active thyroid glands, which conceivably contributed to their suppressed growth (previously reported) relative to the heavier OS1 nestlings with more active thyroid glands. Thyroid gland activity was more influenced by the chicks' accumulation of (muscle), than exposure (feces) to naphthalene, C2-naphthalenes, and C1-fluorenes. Of four major volatile organic contaminants, sulfur dioxide (SO2) primarily influenced thyroid gland activity and structure, supporting previous findings with captive birds. When collectively considering environmental-thyroidal stressors, chicks had a greater thyroidal response when they experienced colder temperatures, accumulated more C2-naphthalenes, and consumed aquatic-emerging insects with higher PAC burdens than terrestrial insects (carbon (δ13C)). We hypothesize that the more active thyroid glands and higher circulating TT4 of the OS1 chicks supported their growth and survival despite having the highest PAC burdens, whereas the lack of thyroid response in the OS2 chicks combined with high PAC burdens, contributed to their smaller size, poorer condition and poorer survival.
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Affiliation(s)
- K J Fernie
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment and Climate Change Canada, Burlington, Ontario, Canada L7R 1A2.
| | - S C Marteinson
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment and Climate Change Canada, Burlington, Ontario, Canada L7R 1A2
| | - D Chen
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, Guangdong 510632, China
| | - V Palace
- International Institute for Sustainable Development - Experimental Lakes Area, 111 Lombard Avenue, Suite 325, Winnipeg, Manitoba, Canada R3B 0T4
| | - L Peters
- Riddell Faculty of Earth Environment and Resources, University of Manitoba, 125 Dysart Road, Winnipeg, Manitoba, Canada R3T 2N2
| | - C Soos
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment and Climate Change Canada, 115 Perimeter Rd, Saskatoon, Saskatchewan, Canada S7N 0X4
| | - J E G Smits
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive NW, Calgary, Alberta, Canada T2N 4Z6
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Fernie KJ, Marteinson SC, Soos C, Chen D, Cruz-Martinez L, Smits JEG. Reproductive and developmental changes in tree swallows (Tachycineta bicolor) are influenced by multiple stressors, including polycyclic aromatic compounds, in the Athabasca Oil Sands. Environ Pollut 2018; 238:931-941. [PMID: 29684897 DOI: 10.1016/j.envpol.2018.03.074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 03/19/2018] [Accepted: 03/20/2018] [Indexed: 05/05/2023]
Abstract
Mining in the Athabasca Oil Sands Region (AOSR) has contributed extensively to increased exposure of wildlife to naturally occurring polycyclic aromatic compounds (PACs), yet little is known about the toxicity of PACs to wildlife in this region. We identified reproductive and developmental changes in tree swallows (Tachycineta bicolor) breeding in close proximity to mining-related activities in the AOSR, and determined these changes in relation to the birds' exposure and accumulation of 41 PACs (parent-, alkylated-PAHs), dibenzothiophenes (DBTs; previously published), diet (carbon (δ13C), nitrogen (δ15N)), volatile organic compounds, and weather variables. Tree swallow pairs (N = 43) were compared among mining-related (OS1, OS2) and reference (REF1, REF2) sites. At OS2, clutch initiation was slightly advanced (2012) but reproductive success (65%) was much lower than at the other sites (≥ 79%). Fledgling production by each pair was influenced by the timing of clutch initiation (years combined); in a highly inclement brood rearing period (2013), additional influences included the nestlings' exposure to ΣDBTs, accumulation of C1-naphthalene, the trophic position of the prey in their diet (δ15N), and record-breaking rainfall. Nestlings at OS2 were significantly lighter at day (d) 9 and d14, and in poorer body condition (d9). Nestling body mass was influenced by multiple stressors that varied by site: mass of younger nestlings (d9) was related to dietary source (δ13C; e.g., wetlands, terrestrial fields), exposure and/or accumulation of C1-phenanthrenes, C2-fluorenes, Σalkyl-PAHs and ΣDBTs, while for older nestlings (d14), body mass was related to sex, hatch date and/or rainfall during brood rearing. The swallows' exposure and accumulation of parent-PACs, alkyl-PACs and DBTs, the timing of hatching, their diet and exposure to highly inclement rains, contributed to their reproductive and developmental changes.
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Affiliation(s)
- K J Fernie
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment and Climate Change Canada, Burlington, Ontario, L7R 1A2, Canada.
| | - S C Marteinson
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment and Climate Change Canada, Burlington, Ontario, L7R 1A2, Canada
| | - C Soos
- Ecotoxicology & Wildlife Health Division, Science & Technology Branch, Environment and Climate Change Canada, 115 Perimeter Rd, Saskatoon, Saskatchewan, S7N 0X4, Canada
| | - D Chen
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, Guangdong, 510632, China
| | - L Cruz-Martinez
- Biomedical Sciences, Ross University School of Veterinary Medicine, St. Kitts, West Indies; Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive NW Calgary, Alberta, T2N 4Z6, Canada
| | - J E G Smits
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive NW Calgary, Alberta, T2N 4Z6, Canada
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Fernie KJ, Letcher RJ. Waste-water treatment plants are implicated as an important source of flame retardants in insectivorous tree swallows (Tachicyneta bicolor). Chemosphere 2018; 195:29-39. [PMID: 29248750 DOI: 10.1016/j.chemosphere.2017.12.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/03/2017] [Accepted: 12/06/2017] [Indexed: 06/07/2023]
Abstract
Wastewater treatment plants (WWTPs) are an important source of anthropogenic chemicals, including organic flame retardants (FRs). Limited studies indicate birds can be exposed to FRs by feeding from waters receiving WWTP effluent or in fields receiving biosolids. Expanding on our earlier study, 47 legacy and 18 new FR contaminants were characterized in the eggs of insectivorous tree swallows (Tachycineta bicolor) feeding in water bodies receiving effluent from two WWTPs and compared to those from a reference site 19 km downstream of the nearest WWTP. Of the FRs measured, polybrominated diphenyl ethers (PBDEs) dominated the FR profile, specifically BDE-47, -99, -100, -153, -154, with considerably lower concentrations of hexabromocyclododecane (HBCDD), BDE-183 and BDE-209; each detected in 96-100% of the eggs overall except HBCDD (83%). FR concentrations were usually significantly greater in eggs from the secondary WWTP versus the tertiary WWTP and/or reference site. Despite low detection rates, concentrations of new FRs, specifically pentabromobenzyl acrylate (PBBA), 1,2,-bis-(2,4,6-tribromophenoxy)ethane (BTBPE), bis(2-ethylhexyl)-tetrabromophthalate (BEHTBP), tetrabromo-o-chlorotoluene (TBCT), hexabromobenzene (HBB), α- and β-1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane (DBE-DBCH), were greater than HBCDD or BDE-209. Additional evidence that WWTPs are an important source of exposure to new FR contaminants for birds utilizing associated water bodies is that only the WTTP eggs, not the reference eggs, had measureable concentrations of PBBA, TBCT, BEHTBP, HBB, α-DBE-DBCH, 2,2',4,5,5'-pentabromobiphenyl (BB-101), pentabromoethyl benzene (PBEB), 2,4,6-tribromophenyl allyl ether (TBPAE), and tetrabromo-p-xylene (pTBX). Our study suggests that WWTPs are an important source of legacy and new FR contaminants for birds consuming prey that are associated with WWTP out-flows.
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Affiliation(s)
- Kimberly J Fernie
- Ecotoxiciology and Wildlife Health Division, Environment and Climate Change Canada, Canada Center for Inland Waters, 867 Lakeshore Road, Burlington, Ontario L7R 1A1, Canada.
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, 1125 Colonel By Drive, Ottawa, Ontario K1A 0H3, Canada
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Hebert CE, Popp BN, Fernie KJ, Ka'apu-Lyons C, Rattner BA, Wallsgrove N. Amino Acid Specific Stable Nitrogen Isotope Values in Avian Tissues: Insights from Captive American Kestrels and Wild Herring Gulls. Environ Sci Technol 2016; 50:12928-12937. [PMID: 27786442 DOI: 10.1021/acs.est.6b04407] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Through laboratory and field studies, the utility of amino acid compound-specific nitrogen isotope analysis (AA-CSIA) in avian studies is investigated. Captive American kestrels (Falco sparverius) were fed an isotopically characterized diet and patterns in δ15N values of amino acids (AAs) were compared to those in their tissues (muscle and red blood cells) and food. Based upon nitrogen isotope discrimination between diet and kestrel tissues, AAs could mostly be categorized as source AAs (retaining baseline δ15N values) and trophic AAs (showing 15N enrichment). Trophic discrimination factors based upon the source (phenylalanine, Phe) and trophic (glutamic acid, Glu) AAs were 4.1 (muscle) and 5.4 (red blood cells), lower than those reported for metazoan invertebrates. In a field study involving omnivorous herring gulls (Larus argentatus smithsonianus), egg AA isotopic patterns largely retained those observed in the laying female's tissues (muscle, red blood cells, and liver). Realistic estimates of gull trophic position were obtained using bird Glu and Phe δ15N values combined with β values (difference in Glu and Phe δ15N in primary producers) for aquatic and terrestrial food webs. Egg fatty acids were used to weight β values for proportions of aquatic and terrestrial food in gull diets. This novel approach can be applied to generalist species that feed across ecosystem boundaries.
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Affiliation(s)
- C E Hebert
- Environment and Climate Change Canada, Science and Technology Branch, National Wildlife Research Centre , Ottawa, ON K1A 0H3, Canada
| | - B N Popp
- Department of Geology and Geophysics, University of Hawaii , Honolulu, Hawaii 96822, United States
| | - K J Fernie
- Environment and Climate Change Canada, Science and Technology Branch, Canada Centre for Inland Waters , Burlington, ON L7R 4A6, Canada
| | - C Ka'apu-Lyons
- Department of Geology and Geophysics, University of Hawaii , Honolulu, Hawaii 96822, United States
| | - B A Rattner
- United States Geological Survey, Patuxent Wildlife Research Center , Beltsville, Maryland 20705, United States
| | - N Wallsgrove
- Department of Geology and Geophysics, University of Hawaii , Honolulu, Hawaii 96822, United States
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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. Environ Res 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Marteinson SC, Letcher RJ, Fernie KJ. Exposure to the androgenic brominated flame retardant 1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane alters reproductive and aggressive behaviors in birds. Environ Toxicol Chem 2015; 34:2395-2402. [PMID: 26013366 DOI: 10.1002/etc.3078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Revised: 04/27/2015] [Accepted: 05/20/2015] [Indexed: 06/04/2023]
Abstract
Detected in environmental samples, 1,2-dibromo-4-(1,2-dibromoethyl) cyclohexane (DBE-DBCH) is a bioaccumulative isomer of a current-use brominated flame retardant. All 4 structural isomers are androgen agonists; however, little toxicological information exists for this compound. The objective of the present study was to determine if β-DBE-DBCH, the isomer found most prominently in animal tissue, affects androgen-dependent behavior of breeding American kestrels (Falco sparverius). The authors hypothesized that if β-DBE-DBCH acts as an androgen agonist in kestrels, androgen-dependent behaviors (i.e., copulation, courtship, aggression) would increase and behaviors inhibited by androgens (i.e., parental care behaviors) would decrease. Sixteen captive experimental kestrel pairs were exposed to 0.239 ng β-DBE-DBCH/g kestrel/d by diet from 4 wk prior to pairing until their nestlings hatched (mean 82 d) and compared with vehicle only-exposed control pairs (n = 15). Androgen-dependent behaviors were significantly increased in β-DBE-DBCH-exposed birds, consistent with the authors' hypothesis. These behavioral changes included copulation and other sexual behaviors in males and females and aggression in males, suggesting that β-DBE-DBCH may have acted like an androgen agonist in these birds. Parental behaviors were not reduced in exposed birds as predicted, although dietary exposure had ceased before chicks hatched. Further assessment of β-DBE-DBCH is recommended given these behavioral changes and the previously reported reproductive changes in the same birds.
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Affiliation(s)
- Sarah C Marteinson
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, Burlington, Ontario, Canada
| | - Robert J Letcher
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada
| | - Kimberly J Fernie
- Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, Burlington, Ontario, Canada
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Fernie KJ, Palace V, Peters LE, Basu N, Letcher RJ, Karouna-Renier NK, Schultz SL, Lazarus RS, Rattner BA. Investigating endocrine and physiological parameters of captive American kestrels exposed by diet to selected organophosphate flame retardants. Environ Sci Technol 2015; 49:7448-55. [PMID: 25988605 DOI: 10.1021/acs.est.5b00857] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Organophosphate triesters are high production volume additive flame retardants (OPFRs) and plasticizers. Shown to accumulate in abiotic and biotic environmental compartments, little is known about the risks they pose. Captive adult male American kestrels (Falco sparverius) were fed the same dose (22 ng OPFR/g kestrel/d) daily (21 d) of tris(2-butoxyethyl) phosphate (TBOEP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), or tris(1,2-dichloro-2-propyl) phosphate (TDCIPP). Concentrations were undetected in tissues (renal, hepatic), suggesting rapid metabolism. There were no changes in glutathione status, indicators of hepatic oxidative status, or the cholinergic system (i.e., cerebrum, plasma cholinesterases; cerebrum muscarinic, nicotinic receptors). Modest changes occurred in hepatocyte integrity and function (clinical chemistry). Significant effects on plasma free triiodothyronine (FT3) concentrations occurred with exposure to TBOEP, TCEP, TCIPP, and TDCIPP; TBOEP and TCEP had additional overall effects on free thyroxine (FT4), whereas TDCIPP also influenced total thyroxine (TT4). Relative increases (32%-96%) in circulating FT3, TT3, FT4, and/or TT4 were variable with each OPFR at 7 d exposure, but limited thereafter, which was likely maintained through decreased thyroid gland activity and increased hepatic deiodinase activity. The observed physiological and endocrine effects occurred at environmentally relevant concentrations and suggest parent OPFRs or metabolites may have been present despite rapid degradation.
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Affiliation(s)
| | - Vince Palace
- ‡Stantec Consulting Ltd., 386 Broadway Avenue, Winnipeg, MB, Canada R3C 3R6
| | - Lisa E Peters
- ‡Stantec Consulting Ltd., 386 Broadway Avenue, Winnipeg, MB, Canada R3C 3R6
| | - Nil Basu
- §McGill University, 21,111 Lakeshore Road, Ste Anne de Bellevue, PQ, Canada H9X 3V9
| | | | - Natalie K Karouna-Renier
- ⊥U.S. Geological Survey, Patuxent Wildlife Research Center, BARC East Building 308, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States
| | - Sandra L Schultz
- ⊥U.S. Geological Survey, Patuxent Wildlife Research Center, BARC East Building 308, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States
| | - Rebecca S Lazarus
- ⊥U.S. Geological Survey, Patuxent Wildlife Research Center, BARC East Building 308, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States
| | - Barnett A Rattner
- ⊥U.S. Geological Survey, Patuxent Wildlife Research Center, BARC East Building 308, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States
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10
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Fernie KJ, King RB, Drouillard KG, Stanford KM. Temporal and spatial patterns of contaminants in Lake Erie watersnakes (Nerodia sipedon insularum) before and after the round goby (Apollonia melanostomus) invasion. Sci Total Environ 2008; 406:344-351. [PMID: 18771794 DOI: 10.1016/j.scitotenv.2008.07.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 07/15/2008] [Accepted: 07/17/2008] [Indexed: 05/26/2023]
Abstract
Temporal and spatial trends in contaminant concentrations were assessed in Lake Erie watersnakes, a threatened (USA)/endangered (Canada) species restricted to western Lake Erie. Temporal changes in plasma contaminant levels were determined in 1990 and 2003, and spatial patterns in 2003 at 12 sites, throughout the species' range. During this period, the watersnakes' diet changed from fish (75%) and amphibians (25%) that avoid zebra mussels, to round gobies (95%) that feed extensively on zebra mussels. Temporal trends indicate that watersnakes on Pelee and North Bass Islands showed a marginal increase in hexachlorobenzene levels, and a significant decline in dieldrin, oxychlordane, and heptachlor epoxide, likely reflecting declines in aerial deposition and clearing of local vineyards. The contaminants with the greatest burdens, sum PCBs and p,p'-DDE, remained stable in the snakes, consistent with trends in other local biota, suggesting that although the dietary switch to round gobies meant consumption of a more contaminated diet, their diet remained at the same trophic position. We suggest that the watersnakes' PCB and p,p'-DDE temporal patterns reflect the lack of change in sediment concentrations with minimal influence from their dietary switch. Similar to top avian predators, PCBs, p,p'-DDE, and technical chlordane, are most prevalent in watersnakes; this ranking remains unchanged. In 2003, the watersnakes demonstrated significant spatial differences in concentrations of p,p'-DDE, dieldrin, technical chlordane and its metabolites. Their 2003 concentrations of p,p'-DDE, and to a lesser extent PCBs, exceed the recommended interim no-observable effects levels on watersnake embryonic survival. Further investigations are required to determine if these higher levels of PCBs, p,p'-DDE, and technical chlordane, affect reproductive and physiological parameters of the Lake Erie watersnake. Until concentrations of sediment contaminants decline in western Lake Erie, these endangered/threatened watersnakes will continue to be exposed to higher concentrations of persistent organic pollutants.
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Affiliation(s)
- K J Fernie
- Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Burlington, ON, Canada L7R 4A6.
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11
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de Solla SR, Fernie KJ, Ashpole S. Snapping turtles (Chelydra serpentina) as bioindicators in Canadian areas of concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants. Environ Pollut 2008; 153:529-536. [PMID: 18039552 DOI: 10.1016/j.envpol.2007.09.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 09/17/2007] [Accepted: 09/23/2007] [Indexed: 05/25/2023]
Abstract
Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities.
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Affiliation(s)
- S R de Solla
- Population Assessment Unit, Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, Canada L7R 4A6.
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12
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De Solla SR, Fernie KJ, Letcher RJ, Chu SG, Drouillard KG, Shahmiri S. Snapping turtles (Chelydra serpentina) as bioindicators in Canadian areas of concern in the Great Lakes Basin. 1. Polybrominated diphenyl ethers, polychlorinated biphenyls, and organochlorine pesticides in eggs. Environ Sci Technol 2007; 41:7252-7259. [PMID: 18044496 DOI: 10.1021/es0710205] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We examined the concentrations and spatial patterns of congeners of PBDEs, PCBs, and organochlorine pesticides in snapping turtle (Chelydra serpentina) eggs from Areas of Concern (AOCs) on the Canadian shores of Lake Ontario, St. Lawrence River, and connecting channels. Eggs from Lyons Creek (Niagara River AOC) reflected a local PCB source over a range of 7.5 km (3.2-10.8) from the Welland Canal. PCB contamination in eggs declined with increasing distance from the Welland Canal, whereas the relative contribution of congeners associated with Aroclor 1248/1254 increased with sigma PCB concentrations. Compared to turtle eggs from other sites in Lake Erie and Lake Ontario, eggs from Lyons Creek and Snye Marsh had PCB congener patterns that reflected a strong contribution from Aroclor 1254. PCBs in the eggs were associated with industrial sources and reflected the composition of different Aroclor technical mixtures. Organochlorine pesticides in eggs tended to be highest at Hamilton Harbour and Bay of Quinte AOCs, and were dominated by DDE, sigma chlordane, and mirex. In contrast, PBDE congener patterns in turtle eggs resembled PentaBDE technical formulations regardless of absolute concentrations or location, and were largely associated with urban environments.
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Affiliation(s)
- S R De Solla
- Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, L7R 4A6, Canada.
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13
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Drouillard KG, Fernie KJ, Letcher RJ, Shutt LJ, Whitehead M, Gebink W, Bird DM. Bioaccumulation and biotransformation of 61 polychlorinated biphenyl and four polybrominated diphenyl ether congeners in juvenile American kestrels (Falco sparverius). Environ Toxicol Chem 2007; 26:313-24. [PMID: 17713220 DOI: 10.1897/06-052r.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
This study examined the bioaccumulation and dietary retention of 61 polychlorinated biphenyl (PCB) and four polybrominated diphenyl ether (PBDE) congeners in juvenile American kestrels (Falco sparverius). American kestrels were exposed to contaminants via egg injection and daily gavage dosing over the posthatch-to-fledgling period. Retention factors for PCBs were dependent on chemical hydrophobicity and chlorine substitution patterns and ranged from less than 1 to 16.4% for PCBs having vicinal hydrogen substitutions at meta-, para- carbons on at least one of the phenyl rings and between 13.2 and 81.5% for congeners containing chlorine substitutions at 4,4'-, 3',4,5'-, 3,4',5-, or 3,3',5,5'-positions. These results indicate that juveniles are capable of biotransforming PCBs according to the same structure-activity rules as adults. A toxicokinetic model, initially parameterized using adult toxicokinetic parameters, was used to describe concentration trends in juveniles over time. The adult model overestimated PCB concentrations but provided an adequate fit when elimination rate constants were increased by a factor of 12.7. Retention factors for the PBDE congeners 2,2',4,4'-tetrabromodiphenyl ether (BDE 47), 2,2',4,4',6-pentabromodiphenyl ether (BDE 100), 2,2',4,4',5-pentabromodiphenyl ether (BDE 99), and 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE 153) were from 7.8 to 45.3% of the total dose. The retention of BDE 47 was similar that observed for readily cleared PCBs, whereas the remaining PBDEs exhibited retention factors consistent with those of persistent PCBs. Half-lives for PBDEs in juveniles were estimated to range from 5.6 to 44.7 d. Assuming differences in PBDE toxicokinetics between juveniles and adults similar to those measured for PCBs, adult American kestrel PBDE half-lives are expected to range from 72 to 572 d.
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Affiliation(s)
- Ken G Drouillard
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, Ontario N9B 3P4, Canada.
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14
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de Solla SR, Martin PA, Fernie KJ, Park BJ, Mayne G. Effects of environmentally relevant concentrations of atrazine on gonadal development of snapping turtles (Chelydra serpentina). Environ Toxicol Chem 2006; 25:520-6. [PMID: 16519315 DOI: 10.1897/05-165r.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The herbicide atrazine has been suspected of affecting sexual development by inducing aromatase, resulting in the increased conversion of androgens to estrogens. We used snapping turtles (Chelydra serpentina), a species in which sex is dependent on the production of estrogen through aromatase activity in a temperature-dependent manner, to investigate if environmentally relevant exposures to atrazine affected gonadal development. Eggs were incubated in soil to which atrazine was applied at a typical field application rate (3.1 L/ha), 10-fold this rate (31 L/ha), and a control rate (no atrazine) for the duration of embryonic development. The incubation temperature (25 degrees C) was selected to produce only males. Although some males with testicular oocytes and females were produced in the atrazine-treated groups (3.3-3.7%) but not in the control group, no statistical differences were found among treatments. Furthermore, snapping turtle eggs collected from natural nests in a corn field were incubated at the pivotal temperature (27.5 degrees C) at which both males and females normally would be produced, and some males had oocytes in the testes (15.4%). The presence of low numbers of males with oocytes may be a natural phenomenon, and we have limited evidence to suggest that the presence of normal males with oocytes may represent a feminizing effect of atrazine. Histological examination of the thyroid gland revealed no effect on thyroid morphology.
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Affiliation(s)
- Shane R de Solla
- Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, Ontario.
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15
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de Solla SR, Fernie KJ. Characterization of contaminants in snapping turtles (Chelydra serpentina) from Canadian Lake Erie Areas of Concern: St. Clair River, Detroit River, and Wheatley Harbour. Environ Pollut 2004; 132:101-112. [PMID: 15276278 DOI: 10.1016/j.envpol.2004.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2003] [Accepted: 03/26/2004] [Indexed: 05/24/2023]
Abstract
PCBs, organochlorine pesticides and dioxins/furans in snapping turtle eggs and plasma (Chelydra serpentina) were evaluated at three Areas of Concern (AOCs) on Lake Erie and its connecting channels (St. Clair River, Detroit River, and Wheatley Harbour), as well as two inland reference sites (Algonquin Provincial Park and Tiny Marsh) in 2001-2002. Eggs from the Detroit River and Wheatley Harbour AOCs had the highest levels of p,p'-DDE (24.4 and 57.9 ng/g) and sum PCBs (928.6 and 491.0 ng/g) wet weight, respectively. Contaminant levels in eggs from St. Clair River AOC were generally higher than those from Algonquin Park, but similar to those from Tiny Marsh. Dioxins appeared highest from the Detroit River. The PCB congener pattern in eggs suggested that turtles from the Detroit River and Wheatley Harbour AOCs were exposed to Aroclor 1260. TEQs of sum PCBs in eggs from all AOCs and p,p'-DDE levels in eggs from the Wheatley Harbour and the Detroit River AOCs exceeded the Canadian Environmental Quality Guidelines. Furthermore, sum PCBs in eggs from Detroit River and Wheatley Harbour exceeded partial restriction guidelines for consumption. Although estimated PCB body burdens in muscle tissue of females were well below consumption guidelines, estimated residues in liver and adipose were above guidelines for most sites.
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Affiliation(s)
- Shane R de Solla
- Canadian Wildlife Service, Canada Centre for Inland Waters, 867 Lakeshore Road, Box 5050, Burlington, ON, L7R 4A6
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16
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Bortolotti GR, Fernie KJ, Smits JE. Carotenoid concentration and coloration of American Kestrels (Falco sparverius
) disrupted by experimental exposure to PCBs. Funct Ecol 2003. [DOI: 10.1046/j.1365-2435.2003.00778.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Smits JE, Fernie KJ, Bortolotti GR, Marchant TA. Thyroid hormone suppression and cell-mediated immunomodulation in American kestrels (Falco sparverius) exposed to PCBs. Arch Environ Contam Toxicol 2002; 43:338-344. [PMID: 12202931 DOI: 10.1007/s00244-002-1200-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Exposure to environmental contaminants can induce physiological changes in animals through various mechanisms. One manifestation of subclinical toxicity from polychlorinated biphenyl (PCB) exposure is the disruption of normal immune function described in numerous species, including American kestrels (Falco sparverius). In 1998, 152 mature male and female kestrels were fed either a mixture of Aroclor 1248:1254:1260 (approximately 7 mg/kg kestrel/day) through their food items, or control diets. Offspring produced by 50 breeding pairs (thus, half received in ovo PCB exposure only) were also studied. Total and differential white blood cell counts, the phytohemagglutinin (PHA) skin response, as well as thyroid hormone levels were tested in vivo in nonbreeding adults (1998 only) and nestlings (1998 and 1999). In 1999, nestlings came from three parental groups; adults exposed in 1998, birds produced by PCB-exposed parents, and unexposed birds. In 1998, directly exposed males but not females had increased total white blood cell counts driven by lymphocytosis, plus a decreased heterophil-to-lymphocyte ratio relative to controls. PCB-exposed birds had a significantly greater response to PHA than did controls, with sex as a significant factor and plasma triiodothyonine (T(3)) as a significant covariate. Levels of T(3) were significantly depressed in PCB-exposed birds of both sexes. The 1999 nestlings (F1 generation with respect to PCB exposure) did not show any effect of parental treatment group on the PHA skin response, yet T(3) remained as a significant covariate. Immunological effects are discussed in light of the antibody-mediated immunotoxicity found in the same birds and reported previously.
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Affiliation(s)
- J E Smits
- Toxicology Centre and Veterinary Pathology, University of Saskatchewan, 44 Campus Drive, Saskatoon, Saskatchewan S7N 5B3, Canada.
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18
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Drouillard KG, Fernie KJ, Smits JE, Bortolotti GR, Bird DM, Norstrom RJ. Bioaccumulation and toxicokinetics of 42 polychlorinated biphenyl congeners in American kestrels (Falco sparverius). Environ Toxicol Chem 2001; 20:2514-2522. [PMID: 11699777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The bioaccumulation and toxicokinetics of 42 polychlorinated biphenyls (PCBs) was determined in male American kestrels exposed to an Aroclor-contaminated diet for 120 d followed by a 348-d depuration period. The birds were housed under ambient outdoor temperatures to permit normal fluctuations in body weight during the study. Whole body PCB clearance, plasma/fat distribution coefficients, and plasma PCB clearance constants were determined for individual PCBs to calibrate a two-compartment rate constant model in order to describe PCB elimination in the birds. Plasma/fat partition coefficients (K(PF)) averaged 0.0060 +/- 0.0001 for all congeners of study, were not dependent on chemical hydrophobicity, and did not change in summer versus winter sacrificed animals. Plasma clearance constants (k'pc) for PCBs were observed to be dependent on both chlorine substitution patterns and congener hydrophobicity. Polychlorinated biphenyl congeners categorized as readily cleared congeners contained vicinal meta-para hydrogen substituents on at least one phenyl ring, while slowly cleared congeners were chlorine hindered at these positions. A general equation was derived to predict plasma clearance constants for all tri- to octachlorobiphenyls based on the presence of an open meta-para site on one of the phenyl rings and from the n-octanol-water partition coefficient of the chemical. The equation was validated by comparing predicted versus measured relative biomagnification factors of PCBs determined in birds at the end of the dosing period. The two-compartment model calibrated for PCB elimination in American kestrels may be used to describe PCB toxicokinetics in wild birds provided that seasonal fluctuations in the fat content of the modeled population is known.
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Affiliation(s)
- K G Drouillard
- Watershed Ecosystems Program, Trent University, Peterborough, Ontario, Canada.
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Fisher SA, Bortolotti GR, Fernie KJ, Smits JE, Marchant TA, Drouillard KG, Bird DM. Courtship behavior of captive American kestrels (Falco sparverius) exposed to polychlorinated biphenyls. Arch Environ Contam Toxicol 2001; 41:215-220. [PMID: 11462146 DOI: 10.1007/s002440010240] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2000] [Accepted: 03/19/2001] [Indexed: 05/23/2023]
Abstract
Polychlorinated biphenyls (PCBs) adversely affect reproduction in birds. Captive adult male and female American kestrels (Falco sparverius) were studied to investigate the potential behavioral and hormonal alterations during the courtship period resulting from clinical exposure to PCBs. American kestrels ingested 7 mg/kg/body weight/bird/day of a 1:1:1 mixture of Aroclors 1248, 1254, and 1260 through their diet of day-old cockerels. The dietary dosage of Aroclors resulted in environmentally relevant total PCB residues in the eggs, averaging 34.1 microg/g wet weight (geometric mean). There was no difference between treatment and control birds in the circulating levels of total androgens (p = 0.44) or in 17 beta-estradiol (p = 0.29), one week following pairing. Male kestrels exposed to dietary PCBs exhibited significantly more sexual behaviors (p = 0.034) and flight behaviors (p = 0.026) than the control males. Sexual behaviors of male kestrels included; nest-box inspections, solicitation of copulation, the offer of food to the female, and giving the female food. The flight behaviors of the male included; flying from one perch to another and aerial display. In addition, the frequency of male sexual behaviors were correlated (r = 0.605, p = 0.001) with total PCB residues in the eggs of their mates. A concurrent study found that these same PCB-exposed kestrels experienced a delay in clutch initiation as well as a greater number of completely infertile clutches.
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Affiliation(s)
- S A Fisher
- Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada
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Abstract
Exposure to electromagnetic fields (EMFs) alters melatonin, behavior, growth, and reproduction of captive American kestrels (Falco sparverius), particularly of males. EMF exposure is a "possible" human carcinogen and associated with some neurodegenerative diseases. Oxidative stress contributes to cancer, neurodegenerative diseases, and immune disorders. We tested whether EMF exposure elicits an avian immune response and alters oxidative stress levels. Captive male kestrels were bred under control or EMF conditions equivalent to those experienced by wild kestrels. Short-term EMF exposure (one breeding season) suppressed plasma total proteins, hematocrits, and carotenoids in the first half of the breeding season. It also suppressed erythrocyte cells and lymphocyte proportions, but elevated granulosa proportions at the end of the breeding season. Long-term EMF exposure (two breeding seasons) suppressed hematocrits in the first half of the reproductive period too. Results indicate that only short-term EMF birds experience an immune response, particularly during the early half of the breeding season. The elevation of granulocytes, and the suppression of carotenoids, total proteins, and previously melatonin in the same kestrels, signifies that the short-term EMF male kestrels had higher levels of oxidative stress, due to an immune response and/or EMF exposure. Long-term EMF exposure may be linked to higher levels of oxidative stress through EMF exposure only.
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Affiliation(s)
- K J Fernie
- Avian Science and Conservation Centre, McGill University, Ste Anne de Bellevue, Quebec, H9X 3V9, Canada.
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Fernie KJ, Smits JE, Bortolotti GR, Bird DM. In ovo exposure to polychlorinated biphenyls: reproductive effects on second-generation American kestrels. Arch Environ Contam Toxicol 2001; 40:544-550. [PMID: 11525498 DOI: 10.1007/s002440010208] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The reproductive success of wild birds has been affected by exposure to multiple contaminants. Reproduction of captive American kestrels (Falco sparverius) was suppressed when adult birds were exposed to dietary polychlorinated biphenyls (PCBs). In this study, the reproductive effects of in ovo exposure to PCBs is explored, along with determining effects on reproduction in second-generation birds indirectly exposed to PCBs. Reproductive changes in this subsequent generation are examined separately in male and female birds. Captive American kestrels (F. sparerius) were hatched from clutches with eggs containing environmentally relevant levels of total PCBs (34.0 microg/g whole egg WW versus 0 microg/g controls); parent birds had been fed PCB-spiked (Aroclor 1248:1254:1260) food (7 mg/kg BW day(-1)) for 100 days until their eggs hatched. In 1999, the second-generation PCB birds were paired with unexposed kestrels having reproductive experience. In ovo PCB exposure suppressed egg laying completely in 25% of PCB females and resulted in delays in clutch initiation and smaller clutch sizes for PCB male and female pairs. There was no evidence in this study of in ovo PCB treatment effects on fertility or hatching success. The decline in reproductive success was also reflected in the reduced fledging success and higher incidence of complete brood mortality of PCB nestlings. Differences between in ovo-exposed PCB males and females but not between controls were evident in reproductive success. In ovo PCB exposure appears to have had greater effects on female kestrels until clutch completion, with a greater time lag between pairing and egg laying, reduced numbers of pairs laying eggs, and smaller clutches being laid. In ovo PCB exposure has greater effects later in the breeding season on male kestrels, which had poorer hatching and fledging success relative to the PCB females. Possible behavioral and physiological mechanisms involved in these reproductive changes are discussed.
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Affiliation(s)
- K J Fernie
- Natural Resource Sciences, McGill University, Ste Anne de Bellevue, Quebec, Canada
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Fernie KJ, Smits JE, Bortolotti GR, Bird DM. Reproduction success of American kestrels exposed to dietary polychlorinated biphenyls. Environ Toxicol Chem 2001; 20:776-781. [PMID: 11345453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
While reproduction of wild birds is adversely affected by multiple environmental contaminants, we determined that polychlorinated biphenyls (PCBs) alone alter reproduction. Captive American kestrels (Falco sparverius), fed PCB-spiked (Aroclor 1248:1254:1260) food (7 mg/kg body weight/d) prior to and during the first breeding season only (100 d) laid eggs with environmentally relevant levels of total PCBs (34.0 microg/g whole egg wet wt vs 0 microg/g for controls). Reproduction changed during, not after, PCB exposure in this two-year study. The PCB-exposed pairs laid smaller clutches later in the season and laid more totally infertile clutches. Hatching success was reduced in PCB-exposed pairs, and 50% of PCB nestlings died within 3 d of hatching. Nearly 60% of PCB-exposed pairs with hatchlings failed to produce fledglings. Higher levels of total PCB residues and congeners were associated with later clutch initiation and fewer fertile eggs, hatchlings, and fledglings. We suggest that nonpersistent PCB congeners have a greater influence on reproduction than do persistent congeners.
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Affiliation(s)
- K J Fernie
- Avian Science and Conservation Centre, McGill University, Sainte Anne de Bellevue, Quebec, Canada.
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Fernie KJ, Bortolotti GR, Smits JE, Wilson J, Drouillard KG, Bird DM. Changes in egg composition of American kestrels exposed to dietary polychlorinated biphenyls. J Toxicol Environ Health A 2000; 60:291-303. [PMID: 10914693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Changes in the quality of eggs of birds exposed to polychlorinated biphenyls (PCBs) have been described, but have never been directly attributed to PCBs. Polychlorinated biphenyl residues in eggs have been associated with reduced reproductive success and embryonic deformities in wild birds. Egg size and composition, specifically the amount of albumen, yolk, and water in an egg, also influence the growth and viability of embryos and hatchlings, and consequently the reproductive success of birds. To deter mine whether PCB exposure of adult birds affected the size and composition of their eggs, 25 pairs of captive American kestrels (Falco sparverius) were fed a mixture of PCB-spiked (1248:1254:1260) food to give an approximate exposure of 7 mg/kg body weight/d, beginning 1 mo prior to pairing, and continuing throughout the courtship, egg-laying, and incubation periods. This dietary level in the adult female kestrels resulted in mean total PCB residues in the eggs of 34.1 microg/g wet weight (geometric mean), which is environmentally relevant. PCB residues in eggs increased with the time of female exposure to the contaminated diet and laying date. Variation in egg size within PCB clutches was significantly greater than within control clutches, although absolute egg mass and volume did not differ markedly by treatment. Only infertile eggs and only one egg per clutch were used for egg composition analysis. Yolks in the PCB-contaminated eggs were heavier, with less wet and dry albumen relative to control eggs. Water content and eggshell thickness were not significantly affected by PCB exposure. These results suggest that eggs from the PCB treatment have relatively more lipid and less protein available for embryonic development. Changes in egg composition were not associated with egg size, lay date, ambient temperature, humidity, or precipitation, which are factors known to affect these variables in bird eggs. The PCB-induced changes in egg composition described here provide insight into possible mechanisms contributing to reduced reproductive performance in wild birds exposed to PCBs.
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Affiliation(s)
- K J Fernie
- Avian Science and Conservation Centre, McGill University, Ste Anne de Bellevue, Quebec, Canada
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Fernie KJ, Leonard NJ, Bird DM. Behavior of free-ranging and captive American kestrels under electromagnetic fields. J Toxicol Environ Health A 2000; 59:597-603. [PMID: 10839495 DOI: 10.1080/009841000156619] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Wild birds, particularly raptors, commonly use electrical transmission structures for nesting, perching, hunting, and roosting. Consequently, birds are exposed to electromagnetic fields (EMFs). The amount of time that wild reproducing American kestrels (Falco sparverius) were exposed to EMFs was determined, and the effects of EMFs on the behavior of captive reproducing kestrels were examined. Wild kestrels were exposed to EMFs for 25% to 75% of the observed time. On a 24-h basis, estimated EMF exposure of wild kestrels ranged from 71% during courtship, to 90% during incubation, similar to that experienced by captive kestrels (88% of a 24-h period). Additionally, captive kestrels were exposed to EMF levels experienced by wild kestrels nesting under 735-kV power lines. Captive EMF females were more active, more alert, and perched on the pen roof more frequently than control females during courtship. EMF females preened and rested less often during brood rearing. EMF male kestrels were more active than control males during courtship, and more alert during incubation. Increased activity of kestrels during courtship may be linked to changes in corticosterone, but likely not melatonin. Observed behavioral changes were unlikely to directly result in the better growth of nestlings and fledging success, or poorer hatching success, of the EMF group, as previously reported. Behavioral changes of captive EMF kestrels may be observed in wild kestrels.
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Affiliation(s)
- K J Fernie
- Avian Science and Conservation Centre, Department of Natural Resource Sciences, McGill University, Ste Anne de Bellevue, Quebec, Canada.
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Abstract
Reduced reproductive success of birds nesting near power lines has been documented but never directly attributed to electromagnetic fields (EMFs). Laboratory studies have identified EMF effects on embryonic development, but reproductive success of wild birds is dependent on additional factors, including fertility, egg size, hatching, and fledging success. We tested whether EMFs affect reproductive success of birds. Captive American kestrels (Falco sparverius) were bred for one season per year for 2 yr under either controlled or EMF conditions. EMF exposure was equivalent to that experienced by wild reproducing kestrels and was weakly associated with reduced egg laying in 1 yr only. In both years fertility was higher, but hatching success was lower in EMF pairs than control pairs. Fledging success was higher in EMF pairs than control pairs in 1995 only. Egg composition and embryonic development were examined in 1 yr only, but hatchlings were measured in both years. EMF eggs were larger, with more yolk, albumen, and water, but had thinner egg shells than control eggs. Late-term EMF embryos were larger and longer than control embryos, although hatchlings were similar in body mass and size. EMF exposure affected reproductive success of kestrels, increasing fertility, egg size, embryonic development, and fledging success but reducing hatching success.
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Affiliation(s)
- K J Fernie
- Avian Science and Conservation Centre, McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec H9X 3V9, Canada.
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Fernie KJ, Bird DM, Petitclerc D. Effects of electromagnetic fields on photophasic circulating melatonin levels in American kestrels. Environ Health Perspect 1999; 107:901-4. [PMID: 10544158 PMCID: PMC1566687 DOI: 10.1289/ehp.99107901] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Birds reproduce within electromagnetic fields (EMFs) from transmission lines. Melatonin influences physiologic and behavioral processes that are critical to survival, and melatonin has been equivocally suppressed by EMFs in mammalian species. We examined whether EMFs affect photophasic plasma melatonin in reproducing adult and fledgling American kestrels (Falco sparverius), and whether melatonin was correlated with body mass to explain previously reported results. Captive kestrel pairs were bred under control or EMF conditions for one (short-term) or two (long-term) breeding seasons. EMF exposure had an overall effect on plasma melatonin in male kestrels, with plasma levels suppressed at 42 days and elevated at 70 days of EMF exposure. The similarity in melatonin levels between EMF males at 42 days and controls at 70 days suggests a seasonal phase-shift of the melatonin profile caused by EMF exposure. Melatonin was also suppressed in long-term fledglings, but not in short-term fledglings or adult females. Melatonin levels in adult males were higher than in adult females, possibly explaining the sexually dimorphic response to EMFs. Melatonin and body mass were not associated in American kestrels. It is likely that the results are relevant to wild raptors nesting within EMFs.
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Affiliation(s)
- K J Fernie
- Natural Resource Sciences, McGill University, Quebec, Canada; Toxicology Centre and Biology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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