RESUMO
During native subsistence hunts from 1987 to 2007, blubber and liver samples from 50 subadult male northern fur seals (Callorhinus ursinus) were collected on St. Paul Island, Alaska. Samples were analyzed for legacy persistent organic pollutants (POPs), recently phased-out/current-use POPs, and vitamins. The legacy POPs measured from blubber samples included polychlorinated biphenyl congeners, DDT (and its metabolites), chlorobenzenes, chlordanes, and mirex. Recently phased-out/current-use POPs included in the blubber analysis were the flame retardants, polybrominated diphenyl ethers, and hexabromocyclododecanes. The chemical surfactants, perfluorinated alkyl acids, and vitamins A and E were assessed in the liver samples. Overall, concentrations of legacy POPs are similar to levels seen in seal samples from other areas of the North Pacific Ocean and the Bering Sea. Statistically significant correlations were seen between compounds with similar functions (pesticides, flame retardants, vitamins). With sample collection spanning two decades, the temporal trends in the concentrations of POPs and vitamins were assessed. For these animals, the concentrations of the legacy POPs tend to decrease or stay the same with sampling year; however, the concentrations of the current-use POPs increased with sampling year. Vitamin concentrations tended to stay the same across the sampling years. With the population of northern fur seals from St. Paul Island on the decline, a detailed assessment of exposure to contaminants and the correlations with vitamins fills a critical gap for identifying potential population risk factors that might be associated with health effects.
Assuntos
Otárias/metabolismo , Hidrocarbonetos Halogenados/metabolismo , Vitaminas/metabolismo , Poluentes Químicos da Água/metabolismo , Tecido Adiposo/metabolismo , Alaska , Animais , Éteres Difenil Halogenados/metabolismo , Bifenilos Policlorados/metabolismo , Vitamina ARESUMO
In the last decade, specific attention has been paid to total mercury (HgT) stable isotopic composition, especially in natural samples such as aquatic organisms, due to its potential to track the cycle of this toxic element in the environment. Here, we investigated Hg Compound Specific stable Isotopic Composition (CSIC) of natural inorganic Hg (iHg) and methylmercury (MMHg) in various tissues of aquatic mammals (Beluga whale from the Arctic marine environment and seals from the freshwater lake Baikal, Russia). In seals' organs the variation in mass dependent fractionation (MDF, δ(202)Hg) for total Hg was significantly correlated to the respective fraction of iHg and MMHg compounds, with MMHg being enriched by â¼ 3 in heavier isotopes relative to iHg. On the other hand, we observe insignificant variation in Hg mass independent isotope fractionation (MIF, Δ(199)Hg) among iHg and MMHg in all organs for the same mammal species and MMHg in prey items. MIF signatures suggest that both MMHg and iHg in aquatic mammals have the same origin (i.e., MMHg from food), and are representative of Hg photochemistry in the water column of the mammal ecosystem. MDF signatures of Hg compounds indicate that MMHg is demethylated in vivo before being stored in the muscle, and the iHg formed is stored in the liver, and to a lesser extent in the kidney, before excretion. Thus, Hg CSIC analysis in mammals can be a powerful tool for tracing the metabolic response to Hg exposure.
Assuntos
Beluga/metabolismo , Caniformia/metabolismo , Isótopos de Mercúrio , Compostos de Metilmercúrio/metabolismo , Animais , Cadeia Alimentar , Cromatografia Gasosa-Espectrometria de Massas , Isótopos de Mercúrio/análise , Isótopos de Mercúrio/química , Isótopos de Mercúrio/metabolismo , Compostos de Metilmercúrio/análise , Distribuição TecidualRESUMO
Decadal time trends of mercury (Hg) concentrations in Arctic biota suggest that anthropogenic Hg is not the single dominant factor modulating Hg exposure to Arctic wildlife. Here, we present Hg speciation (monomethyl-Hg) and stable isotopic composition (C, N, Hg) of 53 Alaskan ringed seal liver samples covering a period of 14 years (1988-2002). In vivo metabolic effects and foraging ecology explain most of the observed 1.6 variation in liver δ(202)Hg, but not Δ(199)Hg. Ringed seal habitat use and migration were the most likely factors explaining Δ(199)Hg variations. Average Δ(199)Hg in ringed seal liver samples from Barrow increased significantly from +0.38 ± 0.08 (±SE, n = 5) in 1988 to +0.59 ± 0.07 (±SE, n = 7) in 2002 (4.1 ± 1.2% per year, p < 0.001). Δ(199)Hg in marine biological tissues is thought to reflect marine Hg photochemistry before biouptake and bioaccumulation. A spatiotemporal analysis of sea ice cover that accounts for the habitat of ringed seals suggests that the observed increase in Δ(199)Hg may have been caused by the progressive summer sea ice disappearance between 1988 and 2002. While changes in seal liver Δ(199)Hg values suggests a mild sea ice control on marine MMHg breakdown, the effect is not large enough to induce measurable HgT changes in biota. This suggests that Hg trends in biota in the context of a warming Arctic are likely controlled by other processes.
Assuntos
Monitoramento Ambiental , Camada de Gelo , Marcação por Isótopo , Focas Verdadeiras/metabolismo , Alaska , Animais , Regiões Árticas , Ecossistema , Geografia , Fígado/metabolismo , Isótopos de Mercúrio/análise , Fatores de TempoRESUMO
Environmental specimen banks (ESBs) are facilities that archive samples from the environment for future research and monitoring purposes. In addition, the long-term preservation of representative specimens is an important complement to environmental research and monitoring. Today, environmental specimen banking is experiencing a renaissance due to an increase in regulatory interest in ESB biota standards and trend data. The International Environmental Specimen Bank Group (IESB) promotes the worldwide development of techniques and strategies of environmental specimen banking and the international cooperation and collaboration among national ESBs. In order to provide a current and comprehensive overview on international environmental specimen banking activities, a questionnaire was sent to the national ESBs and asked for detailed information on the respective ESBs. The results show the rich diversity of national sampling programs, including more detailed information on archived samples, sampling strategies, and studies that have already been performed in the respective countries. All ESBs completing the survey expressed a strong interest in cooperating with other ESBs on a collaborative project. The collected information of national ESBs is intended to be made publicly available.
Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/química , Internacionalidade , Bancos de Espécimes Biológicos , Conservação dos Recursos Naturais , Coleta de Dados , Monitoramento Ambiental/economia , Humanos , Política Pública , Inquéritos e QuestionáriosRESUMO
Environmental specimen banks (ESBs) have been a fundamental tool for many nations to monitor contaminant temporal and spatial trends, study fate and transport, and assess the severity and risks of pollution. The specimens archived in ESBs are among the longest time-series, most geographically robust, and highest integrity samples available for performing environmental research. Mercury (Hg) remains one of the world's most ubiquitous environmental contaminants, and ESBs have played a prominent role in Hg research. Historically this has involved measuring concentrations of Hg species in various environmental matrices, but the emerging field of Hg stable isotope research provides a new analytical approach that can augment these traditional techniques. Signatures of Hg isotope fractionation have been effectively used for source apportionment and for elucidating Hg biogeochemical cycling. As the research surrounding Hg stable isotopes continues to mature, ESBs can play a useful role in analytical quality control, provide a robust and economical sample archive to expand and diversify the inventory of Hg isotope measurements, and be used to develop and test hypotheses to evaluate whether broadly prevailing paradigms are supported. Samples archived in ESBs are available for request by external collaborators in order to perform high impact research, and should be utilized more effectively to address emerging global environmental concerns.
Assuntos
Bancos de Espécimes Biológicos , Monitoramento Ambiental/métodos , Isótopos de Mercúrio/análise , Mercúrio/análise , Poluentes Químicos da Água/análise , EcossistemaRESUMO
Remote locations, such as the Arctic, are often sinks for persistent contaminants which can ultimately bioaccumulate in local wildlife. Assessing temporal contaminant trends in the Arctic is important in understanding whether restrictions on legacy persistent organic pollutants (POPs) have led to concentration declines. Beluga whale (Delphinapterus leucas) tissue samples were collected from two subpopulations (Cook Inlet, Alaska and the eastern Chukchi Sea) between 1989 and 2006. Several POPs (polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethane and related compounds (DDTs), chlordanes, hexachlorocyclohexanes (HCHs), chlorobenzenes, mirex, polybrominated diphenyl ethers (PBDEs) and semi-quantitatively hexabromocyclododecanes (HBCDs)) were measured in 70 blubber samples, and total mercury (Hg) was measured in 67 liver samples from a similar set of individuals. Legacy POPs (PCBs, chlordanes, DDTs, and HCHs) were the predominant organic compound classes in both subpopulations, with median concentrations of 2360ng/g lipid for Σ80PCBs and 1890 ng/g lipid for Σ6DDTs. Backward stepwise multiple regressions showed that at least one of the four independent variables (subpopulation, sampling year, sex, and animal length) influenced the POP and Hg concentrations. ΣPCBs, ΣDDTs, Σchlordanes, Σchlorobenzenes, mirex, and Hg were significantly higher in belugas from the eastern Chukchi Sea than from the Cook Inlet (p≤0.0001). In contrast, Σ8PBDE and α-HBCD concentrations were significantly lower in belugas from the eastern Chukchi Sea than from the Cook Inlet (p<0.0001). Significant temporal increases in concentrations of Σ8PBDE and α-HBCD were observed for both subpopulations (p≤0.0003), and temporal declines were seen for ΣHCHs and Σchlorobenzenes in eastern Chukchi Sea belugas only (p≤0.0107). All other POP and Hg concentrations were stable, indicating either a lagging response of the Arctic to source reductions or the maintenance of concentrations by unregulated sources. Sex and length also significantly influenced some concentrations, and these findings are discussed.
Assuntos
Mercúrio/análise , Poluentes Químicos da Água/análise , Alaska , Animais , Beluga , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em TandemRESUMO
Elevated mercury concentrations ([Hg]) were found in Alaskan murre (Uria spp.) eggs from the coastal embayment of Norton Sound relative to insular colonies in the northern Bering Sea-Bering Strait region. Stable isotopes of Hg, carbon, and nitrogen were measured in the eggs to investigate the source of this enrichment. Lower δ(13)C values in Norton Sound eggs (-23.3 to -20.0) relative to eggs from more oceanic colonies (-20.9 to -18.7) indicated that a significant terrestrial carbon source was associated with the elevated [Hg] in Norton Sound, implicating the Yukon River and smaller Seward Peninsula watersheds as the likely Hg source. The increasing [Hg] gradient extending inshore was accompanied by strong decreasing gradients of δ(202)Hg and Δ(199)Hg in eggs, indicating lower degrees of mass-dependent (MDF) and mass-independent Hg fractionation (MIF) (respectively) in the Norton Sound food web. Negative or zero MDF and MIF signatures are typical of geological Hg sources, which suggests murres in Norton Sound integrated Hg from a more recent geological origin that has experienced a relatively limited extent of aquatic fractionation relative to more oceanic colonies. The association of low δ(202)Hg and Δ(199)Hg with elevated [Hg] and terrestrial δ(13)C values suggested that Hg stable isotopes in murre eggs effectively differentiated terrestrial/geogenic Hg sources from oceanic reservoirs.
Assuntos
Charadriiformes/metabolismo , Monitoramento Ambiental , Mercúrio/análise , Óvulo/metabolismo , Poluentes Químicos da Água/análise , Animais , Fracionamento Químico , Ecossistema , Marcação por Isótopo , Isótopos de Mercúrio , Oceanos e MaresRESUMO
Mercury concentration ([Hg]), δ(15)N, and δ(13)C values were measured in eggs from common murres (Uria aalge), thick-billed murres (U. lomvia), glaucous gulls (Larus hyperboreus), and glaucous-winged gulls (L. glaucescens) collected in Alaska from 1999 to 2005. [Hg] was normalized to a common trophic level using egg δ(15)N values and published Hg trophic magnification factors. Egg [Hg] was higher in murres from Gulf of Alaska, Cook Inlet, and Norton Sound regions compared to Bering Sea and Bering Strait regions, independent of trophic level. We believe the Yukon River outflow and terrestrial Hg sources on the southern Seward Peninsula are responsible for the elevated [Hg] in Norton Sound eggs. Normalizing for trophic level generally diminished or eliminated differences in [Hg] among taxa, but temporal variability was unrelated to trophic level. Normalizing murre egg [Hg] by trophic level improves the confidence in regional comparisons of Hg sources and biogeochemical cycling in Alaska.
Assuntos
Aves , Monitoramento Ambiental , Poluentes Ambientais/análise , Mercúrio/análise , Óvulo/química , Alaska , Animais , Fenômenos Ecológicos e Ambientais , Poluição Ambiental/estatística & dados numéricos , Cadeia AlimentarRESUMO
Wildlife from remote locations have been shown to bioaccumulate perfluorinated compounds (PFCs) in their tissues. Twelve PFCs, consisting of perfluorinated carboxylic (PFCA) and sulfonic (PFSA) acids as well as the perfluorooctane sulfonate (PFOS) precursor perfluorooctane sulfonamide (PFOSA), were measured in livers of 68 beluga whales (Delphinapterus leucas) collected from two subpopulations, Cook Inlet and eastern Chukchi Sea, in Alaska between 1989 and 2006. PFOS and PFOSA were the dominant compounds measured in both beluga stock populations, with overall median concentrations of 10.8 ng/g and 22.8 ng/g, respectively. Long-chain perfluorocarboxylates, PFCAs (9 to 14 carbons), were detected in more than 80% of the samples. Perfluoroundecanoic acid (PFUnA) and perfluorotridecanoic acid (PFTriA) made up a large percentage of the PFCAs measured with median concentrations of 8.49 ng/g and 4.38 ng/g, respectively. To compare differences in location, year, sex, and length, backward stepwise multiple regression models of the individual and total PFC concentrations were used. Spatially, the Cook Inlet belugas had higher concentrations of most PFCAs and PFOS (p < 0.05); however, these belugas had a lower median concentration of PFOSA when compared to belugas from the eastern Chukchi Sea (p < 0.05). Temporal trends indicated most PFCAs, PFHxS, PFOS, and PFOSA concentrations increased from 1989 to 2006 (p < 0.05). Males had significantly higher concentrations of PFTriA, ΣPFCA, and PFOS (p < 0.05). Perfluorononanic acid (PFNA) and PFOS showed a significant decrease in concentration with increasing animal length (p < 0.05). These observations suggest the accumulation of PFCs in belugas is influenced by year, location, sex, and length.
Assuntos
Beluga/metabolismo , Monitoramento Ambiental , Fluorocarbonos/metabolismo , Alaska , Ácidos Alcanossulfônicos/metabolismo , Animais , Regiões Árticas , Feminino , Feto/metabolismo , Modelos Lineares , Fígado/metabolismo , Fatores de TempoRESUMO
The contents from thick-billed murre (Uria lomvia) eggs collected at four Alaskan colonies in 2002 were analyzed for organic contaminants and carbon δ¹³C) and nitrogen (δ¹5N) stable isotopes. Contaminant concentrations in the eggs varied from below detection limits to 230 ng g⻹ wet mass for 4,4'-DDE in one egg from St Lazaria Island in the Gulf of Alaska. Eggs from this colony generally contained higher levels of contaminants and exhibited significantly different patterns compared to eggs from the Bering and Chukchi seas. Stable isotope values also varied geographically; however, these differences appeared to be related to differences in C and N baselines in the food webs instead of differences in prey. Contaminant and stable isotope correlations were inconclusive, suggesting that better information on regional food web differences and differential offloading of contaminants and stable isotopes to the eggs must be obtained before these kinds of data can be fully incorporated into seabird egg contaminant monitoring programs.
Assuntos
Charadriiformes , Hidrocarbonetos Clorados/análise , Óvulo/química , Resíduos de Praguicidas/análise , Bifenilos Policlorados/análise , Alaska , Animais , Isótopos de Carbono/análise , Monitoramento Ambiental , Geografia , Isótopos de Nitrogênio/análiseRESUMO
The National Institute of Standards and Technology (NIST) has a diverse collection of control materials derived from marine mammal blubber, fat, and serum. Standard Reference Material (SRM) 1945 Organics in Whale Blubber was recertified for polychlorinated biphenyl (PCB) congeners, organochlorine pesticides, and polybrominated diphenyl ether (PBDE) congeners. SRM 1945 has also been assigned mass fraction values for compounds not frequently determined in marine samples including toxaphene congeners, coplanar PCBs, and methoxylated PBDE congeners which are natural products. NIST also has assigned mass fraction values, as a result of interlaboratory comparison exercises, for PCB congeners, organochlorine pesticides, PBDE congeners, and fatty acids in six homogenate materials produced from marine mammal blubber or serum. The materials are available from NIST upon request; however, the supply is very limited for some of the materials. The materials include those obtained from pilot whale blubber (Homogenates III and IV), Blainville's beaked whale blubber (Homogenate VII), polar bear fat (Homogenate VI), and California sea lion serum (Marine Mammal Control Material-1 Serum) and blubber (Homogenate V).
Assuntos
Poluentes Ambientais/análise , Gorduras/análise , Gorduras/normas , Ácidos Graxos/análise , Hidrocarbonetos Halogenados/análise , Animais , Feminino , Masculino , Padrões de Referência , Leões-Marinhos , Ursidae , BaleiasRESUMO
Gull eggs have been used to monitor contaminants in many parts of the world. The Seabird Tissue Archival and Monitoring Project (STAMP) is a long-term program designed to track trends in pollutants in northern marine environments using seabird eggs. Glaucous and glaucous-winged gull (Larus hyperboreus and Larus glaucescens) eggs collected in 2005 from seven Alaskan colonies were analyzed for organic contaminants. Concentrations ranged from below detection limits to 322 ng g(-1) wet mass in one egg for 4,4'-DDE and differed among the samples collected in the Gulf of Alaska and Bering and Chukchi Seas. Chick growth and survival rates may be affected by the contaminant levels found in the eggs, but the eggs should be safe for human consumption if they are eaten in small quantities. STAMP plans to continue collecting and banking gull eggs for future real-time and retrospective analyses.
Assuntos
Charadriiformes/metabolismo , Ovos/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Compostos Orgânicos/análise , Alaska , Animais , Feminino , Exposição Materna , Fatores de TempoRESUMO
Hexabromocyclododecane (HBCD) is a brominated flame retardant used primarily in expanded polystyrene foams and other styrene resins. Samples of blubber (n = 57) and liver (n = 16) from Atlantic white-sided dolphins, Lagenorhynchus acutus, that stranded on the eastern coast of United States between 1993 and 2004 were obtained from the National Marine Mammal Tissue Bank (NMMTB). Blubber samples from most of these animals (n = 47) were previously analyzed for polybrominated diphenyl ethers (PBDE), polychlorinated biphenyls (PCB), and several toxaphene congeners. The three most abundant diastereomers in the technical HBCD mixture (alpha-HBCD, beta-HBCD, and gamma-HBCD) and their enantiomers were determined using liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS). alpha-HBCD was found in all blubber and liver samples while beta-HBCD and gamma-HBCD were not detected in any samples. The alpha-HBCD concentration in blubber and liver ranged from 14 ng/g wet mass (19 ng/g lipid) to 280 ng/g wet mass (380 ng/g lipid) and 0.051 ng/g wet mass (2.9 ng/g lipid) to 3.6 ng/g wet mass (140 ng/g lipid), respectively. Concentrations of alpha-HBCD were 2 to 3 orders of magnitude lower than previously reported PBDE, PCB, and toxaphene concentrations in these same animals. There was not a significant temporal trend for these compounds in white-sided dolphin blubber. The enantiomeric fractions (EF) measured in blubber and liver were not statistically different and ranged from 0.34 to 0.53. Blubber EFs were significantly correlated with both alpha-HBCD concentrations and white-sided dolphin body length. In general, concentrations of HBCDs were lower in these white-sided dolphins than in cetaceans from Western Europe.
Assuntos
Tecido Adiposo/metabolismo , Hidrocarbonetos Bromados/farmacocinética , Fígado/metabolismo , Animais , Cromatografia Líquida , Golfinhos , Espectrometria de Massas , Controle de Qualidade , Estereoisomerismo , Distribuição TecidualRESUMO
Two speciated isotope dilution (SID) approaches consisting of a single-spike (SS) method and a double-spike (DS) method including a reaction/transformation model for the correction of inadvertent transformations affecting mercury species were compared in terms of accuracy, method performance, and robustness for the simultaneous determination of methylmercury (MeHg), inorganic mercury (iHg), and total mercury (HgT) concentrations in five biological Standard Reference Materials (SRMs). The SRMs consisted of oyster and mussel tissue materials displaying different mercury species concentration levels and different textural/matrix properties including freeze-dried (FD) materials (SRMs 1566b, 2976, and 2977) and cryogenically prepared and stored fresh-frozen (FF) materials (SRMs 1974a, 1974b). Each sample was spiked with (201)iHg (Oak Ridge National Laboratory, ORNL) and Me(202)Hg (Institute for Reference Materials and Measurements. IRMM-670) solutions and analyzed using alkaline microwave digestion, ethylation, and gas chromatography inductively coupled plasma mass spectrometry (GC/ICP-MS). The results obtained by the SS-SID method suggested that FF and FD materials are not always commutable for the simultaneous determination of iHg, MeHg, and HgT, due to potential transformation reactions resulting probably from the methodology and/or from the textural/matrix properties of the materials. These transformations can occasionally significantly affect mercury species concentration results obtained by SS-SID, depending on the species investigated and the materials considered. The results obtained by the DS-SID method indicated that the two classes of materials were commutable. The simultaneous and corrected concentrations of iHg, MeHg, and HgT obtained by this technique were not found to be statistically different form the certified and reference concentration together with their expanded uncertainty budgets for the five SRMs investigated, exemplifying the robustness, the accuracy, and the improved commutability of this method compared to SS-SID measurements.
Assuntos
Bivalves/química , Criopreservação , Mercúrio/análise , Compostos de Metilmercúrio/análise , Alimentos Marinhos/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Isótopos de Mercúrio/análise , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
An accurate, ultra-sensitive and robust method for speciation of mono, di, and tributyltin (MBT, DBT, and TBT) by speciated isotope-dilution gas chromatography-inductively coupled plasma-mass spectrometry (SID-GC-ICPMS) has been developed for quantification of butyltin concentrations in cryogenic biological materials maintained in an uninterrupted cryo-chain from storage conditions through homogenization and bottling. The method significantly reduces the detection limits, to the low pg g(-1) level (as Sn), and was validated by using the European reference material (ERM) CE477, mussel tissue, produced by the Institute for Reference Materials and Measurements. It was applied to three different cryogenic biological materials-a fresh-frozen mussel tissue (SRM 1974b) together with complex materials, a protein-rich material (whale liver control material, QC03LH03), and a lipid-rich material (whale blubber, SRM 1945) containing up to 72% lipids. The commutability between frozen and freeze-dried materials with regard to spike equilibration/interaction, extraction efficiency, and the absence of detectable transformations was carefully investigated by applying complementary methods and by varying extraction conditions and spiking strategies. The inter-method results enabled assignment of reference concentrations of butyltins in cryogenic SRMs and control materials for the first time. The reference concentrations of MBT, DBT, and TBT in SRM 1974b were 0.92 +/- 0.06, 2.7 +/- 0.4, and 6.58 +/- 0.19 ng g(-1) as Sn (wet-mass), respectively; in SRM 1945 they were 0.38 +/- 0.06, 1.19 +/- 0.26, and 3.55 +/- 0.44 ng g(-1), respectively, as Sn (wet-mass). In QC03LH03, DBT and TBT concentrations were 30.0 +/- 2.7 and 2.26 +/- 0.38 ng g(-1) as Sn (wet-mass). The concentration range of butyltins in these materials is one to three orders of magnitude lower than in ERM CE477. This study demonstrated that cryogenically processed and stored biological materials are a promising alternative to conventional freeze-dried materials for organotin speciation analysis, because these are, at present, the best conditions for minimizing degradation of thermolabile species and for long-term archival. Finally, the potential of the analytical method was illustrated by analysis of polar bear (Ursus maritimus) and beluga whale (Delphinapterus leuca) liver samples that had been collected in the Arctic and archived at the Marine Environmental Specimen Bank. Significant concentrations of butyltin compounds were found in the samples and provide the first evidence of the presence of this class of contaminant in the Arctic marine ecosystem. Figure Eye catch image.
Assuntos
Técnicas de Química Analítica/métodos , Criopreservação/métodos , Compostos Orgânicos de Estanho/análise , Animais , Regiões Árticas , Beluga , Bivalves , Calibragem , Técnicas de Química Analítica/normas , Congelamento , Fígado/metabolismo , Espectrometria de Massas/métodos , Valores de Referência , Reprodutibilidade dos Testes , Ultrassom , UrsidaeRESUMO
The Seabird Tissue Archival and Monitoring Project (STAMP) is a collaborative Alaska-wide effort by the US Fish and Wildlife Service's Alaska Maritime National Wildlife Refuge (USFWS/AMNWR), the US Geological Survey's Biological Resources Division (USGS/BRD), the Bureau of Indian Affairs Alaska Region Subsistence Branch (BIA/ARSB), and the National Institute of Standards and Technology (NIST) to monitor long-term (decadal) trends in environmental contaminants using seabird eggs. To support this effort, a matrix- (seabird egg) and concentration-specific control material was needed to ensure quality during analytical work. Although a herring gull egg quality assurance (HGQA) material is available from Environment Canada (EC), contaminant concentrations in this material tended to be higher than those observed in Alaskan murre (Uria spp.) eggs. Therefore, to prepare a more appropriate control material, a total of 12 common murre (U. aalge) and thick-billed murre (U. lomvia) eggs from four Bering Sea and Gulf of Alaska nesting locations were cryohomogenized to create 190 aliquots each containing approximately 6 g. This new control material was analyzed by different methods at NIST and EC facilities for the determination of concentrations and value assignment of 63 polychlorinated biphenyl (PCB) congeners, 20 organochlorine pesticides, and 11 polybrominated diphenyl ether (PBDE) congeners. The total PCB concentration is approximately 58 ng g(-1) wet mass. Results obtained for analytes not listed on the certificates of analysis of the previously used control materials, HGQA and NIST's Standard Reference Material (SRM) 1946 Lake Superior Fish Tissue, are also presented.
Assuntos
Charadriiformes/fisiologia , Técnicas de Química Analítica/métodos , Poluentes Ambientais/análise , Óvulo/química , Óvulo/efeitos dos fármacos , Éteres Fenílicos/análise , Bifenil Polibromatos/análise , Bifenilos Policlorados/análise , Alaska , Animais , Técnicas de Química Analítica/normas , Monitoramento Ambiental , Éteres Difenil Halogenados , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
The National Biomonitoring Specimen Bank (NBSB), established in 1979 at the NIST Neutron Research Facility, Gaithersburg, Maryland, was specifically designed to store environmental specimens over long periods of time (50-100 years). This bank contains specimens (e.g., human livers, marine sediments, fish tissues, mussels, oysters, human diet samples, and marine mammal tissues) collected as part of several monitoring and research programs supported by U.S. Federal agencies. In 2002, NIST completed the construction of a second environmental specimen bank facility specifically designed for supporting monitoring and research on marine environmental health issues. This facility, the Marine Environmental Specimen Bank (Marine ESB) is located at the Hollings Marine Laboratory in Charleston, South Carolina, in partnership with a U.S. Federal resource agency, two universities, and a State of South Carolina resource agency. The Marine ESB provides a resource of research specimens that are used to address questions regarding temporal and geographic trends in environmental contamination, genetic separation of populations of animals, and the health status of various types of marine animals. Specimens banked include marine mammal tissues, bird tissues, mussels, and oysters. Plans are underway to establish protocols and initiate banking procedures for other types of marine organisms and environmental materials as part of an expanded effort to support research on the health of marine biota.
Assuntos
Monitoramento Ambiental/métodos , Biologia Marinha , Bancos de Tecidos , Animais , Humanos , Estados UnidosRESUMO
Since 1987, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) has collected tissues from 18 marine mammal species. Specimens are archived in the National Institute of Standards and Technology's National Biomonitoring Specimen Bank (NIST-NBSB). AMMTAP has collected blubber, liver and/or kidney specimens from a number of ringed seals (Phoca hispida) from the areas near Nome and Barrow, Alaska and walruses (Odobenus rosmarus) from several locations in the Bering Sea. Thirty-three ringed seal and 15 walrus blubber samples from the NIST-NBSB were analyzed for persistent organic pollutants (POPs). The compounds determined included PCBs (28 congeners or congener groups), DDT and related compounds, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes, dieldrin, and mirex. POP concentrations in ringed seal blubber were significantly higher in Barrow than in Nome when statistically accounting for the interaction of age and gender; HCB, however, was not statistically different between the two locations. Unlike males, POP concentrations and age were not significantly correlated in females probably as a result of lactational loss. POP concentrations in walrus blubber were lower than in ringed seal blubber for SigmaPCBs, chlordanes, and HCHs, but higher for dieldrin and mirex. POP concentrations in ringed seals and walrus from Alaska provide further evidence that the western Arctic tends to have lower or similar POP concentrations compared to the eastern Canadian Arctic.
Assuntos
Tecido Adiposo/química , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Animais , Caniformia , Monitoramento Ambiental , Feminino , Masculino , Especificidade da EspécieRESUMO
Sixty common murre (Uria aalge) and 27 thick-billed murre (Uria lomvia) eggs collected by the Seabird Tissue Archival and Monitoring Project (STAMP) in 1999-2001 from two Gulf of Alaska and three Bering Sea nesting colonies were analyzed for total mercury (Hg) using isotope dilution cold vapor inductively coupled mass spectrometry. Hg concentrations (wet mass) ranged from 0.011 microg/g to 0.357 microg/g (relative standard deviation = 76%), while conspecifics from the same colonies and years had an average relative standard deviation of 33%. Hg levels in eggs from the Gulf of Alaska (0.166 microg/g +/- 0.011 microg/g) were significantly higher (p < 0.0001) than in the Bering Sea (0.047 microg/g +/- 0.004 microg/g). Within the Bering Sea, Hg was significantly higher (p = 0.0007) in eggs from Little Diomede Island near the arctic than at the two more southern colonies. Although thick-billed and common murres are ecologicallysimilar,there were significant species differences in egg Hg concentrations within each region (p < 0.0001). In the Bering Sea, eggs from thick-billed murres had higher Hg concentrations than eggs from common murres, while in the Gulf of Alaska, common murre eggs had higher concentrations than those of thick-billed murres. A separate one-way analysis of variance on the only time-trend data currently available for a colony (St. Lazaria Island in the Gulf of Alaska) found significantly lower Hg concentrations in common murre eggs collected in 2001 compared to 1999 (p = 0.017). Results from this study indicate that murre eggs may be effective monitoring units for detecting geographic, species, and temporal patterns of Hg contamination in marine food webs. The relatively small intracolony variation in egg Hg levels and the ability to consistently obtain adequate sample sizes both within and among colonies over a large geographic range means that monitoring efforts using murre eggs will have suitable statistical power for detecting environmental patterns of Hg contamination. The potential influences of trophic effects, physical transport patterns, and biogeochemical processes on these monitoring efforts are discussed, and future plans to investigate the sources of the observed variability are presented.