Ecological and spatial factors drive intra- and interspecific variation in exposure of subarctic predatory bird nestlings to persistent organic pollutants

doi:10.1016/j.envint.2013.03.009

Environment International

Volumes 57–58, July 2013, Pages 25-33

https://doi.org/10.1016/j.envint.2013.03.009 Get rights and content

Highlights

•
Body feathers were analysed for persistent organic pollutants and stable isotopes.
•
Predictors of intraspecific exposure were different between species and compounds.
•
Exposure to CB 153, p,p′-DDE and BDE 47 was driven by trophic level and habitat.
•
Exposure to p,p′-DDE and the volatile HCB was driven by inter-annual variation.
•
Interspecific exposure was explained by feeding ecology and regional nest location.

Abstract

Top predators in northern ecosystems may suffer from exposure to persistent organic pollutants (POPs) as this exposure may synergistically interact with already elevated natural stress in these ecosystems. In the present study, we aimed at identifying biological (sex, body condition), ecological (dietary carbon source, trophic level) and spatial factors (local habitat, regional nest location) that may influence intra- and interspecific variation in exposure of subarctic predatory bird nestlings to polychlorinated biphenyl 153 (CB 153), polybrominated diphenyl ether 47 (BDE 47), dichlorodiphenyldichloroethylene (p,p′-DDE) and hexachlorobenzene (HCB). During three breeding seasons (2008–2010), we sampled body feathers from fully-grown nestlings of three ecologically distinct predatory bird species in subarctic Norway: Northern Goshawk (Accipiter gentilis), White-tailed Eagle (Haliaeetus albicilla) and Golden Eagle (Aquila chrysaetos). The present study analysed, for the first time, body feathers for both POPs and carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotopes, thus integrating the dietary carbon source, trophic level and POP exposure for the larger part of the nestling stage.

Intraspecific variation in exposure was driven by a combination of ecological and spatial factors, often different for individual compounds. In addition, combinations for individual compounds differed among species. Trophic level and local habitat were the predominant predictors for CB 153, p,p′-DDE and BDE 47, indicating their biomagnification and decreasing levels according to coast > fjord > inland. Variation in exposure may also have been driven by inter-annual variation arisen from primary sources (e.g. p,p′-DDE) and/or possible revolatilisation from secondary sources (e.g. HCB). Interspecific differences in POP exposure were best explained by a combination of trophic level (biomagnification), dietary carbon source (food chain discrimination) and regional nest location (historical POP contamination).

In conclusion, the combined analysis of POPs and stable isotopes in body feathers from fully-grown nestlings has identified ecological and spatial factors that may drive POP exposure over the larger part of the nestling stage. This methodological approach further promotes the promising use of nestling predatory bird body feathers as a non-destructive sampling strategy to integrate various toxicological and ecological proxies.

Introduction

Being lipophilic and highly resistant to chemical and biological degradation, persistent organic pollutants (POPs) are of concern for the health of ecosystems because of three reasons. Firstly, POPs associate with organic matter, in particular lipids, and therefore potentially bioaccumulate in biological tissues and biomagnify through food chains (Borgå et al., 2012). As a consequence, wildlife feeding at the top of the food chain may bioaccumulate POPs to levels that disrupt immune, endocrine and reproductive systems (Letcher et al., 2010, Sonne, 2010). Secondly, ecosystems are currently still exposed to legacy POPs (Helander et al., 2008, Johansson et al., 2011), even though legal mitigation has been undertaken decades ago (Betts, 2008, Porta and Zumeta, 2002). Thirdly, POPs are subject to long-range atmospheric and hydrologic transport (Lohmann et al., 2007, Möller et al., 2011), rendering anthropogenic pollution with POPs a major environmental threat also to Arctic ecosystems (AMAP, 2011, UNEP/AMAP, 2011).

Arctic populations living at their northernmost distribution are supposedly subject to already high natural stress. Any additional stress from POP exposure may therefore synergistically inflict detrimental health effects (Boonstra, 2004). In order to study POP exposure and its effects, predatory birds are both conceptually (Burger and Gochfeld, 2001) and effectively (Chen and Hale, 2010) valuable sentinels. Recently, Sonne et al., 2010, Sonne et al., 2012 investigated relationships between POP concentrations and clinical–chemical parameters in blood plasma of predatory bird nestlings in northern Norway. Both negative relationships with total bilirubin, glucose, and alanine aminotransferase, and positive relationships with cholesterol, albumin, urea and alkaline phosphatase, suggested that liver, kidney and bone endocrinology and metabolism may have been impacted. This indication of disturbed homeostatic functioning underlines the relevance of the present study.

As often found when assessing wildlife exposure (e.g. Letcher et al., 2010), significant intra- and interspecific variation in POP exposure was recently found in predatory bird nestlings from northern Norway (Eulaers et al., 2011a). It is however unclear which biological variables gave rise to the observed variation. While environmental physico-chemical properties are of importance to determine POP exposure in lower trophic species, dietary accumulation is expected to be the major POP exposure pathway in predatory birds (Ruus et al., 2002). Therefore, the analysis of feeding ecology, by means of carbon and nitrogen stable isotopes (SIs), may be of particular interest in exposure assessment studies (Jardine et al., 2006). The ratio of heavier ¹⁵N to lighter ¹⁴N stable isotopes (δ¹⁵N) typically increases throughout the food chain (Boecklen et al., 2011, Jardine et al., 2006) due to the preferential deamination of light amine groups during de- and transamination processes (Macko et al., 1986). The ratio of stable carbon isotopes (δ¹³C) depicts the food chain origin of the diet, e.g. by discrimination between ¹³C-depleted terrestrial ecosystems compared to enriched marine ones (Boecklen et al., 2011, Jardine et al., 2006).

Recent studies on terrestrial passerines, such as Light-vented Bulbul (Pycnonotus sinensis), Long-tailed Shrike (Lanius schach) and Oriental Magpie-robin (Copsychus saularis; Sun et al., 2012), and marine top predators, such as Bald Eagle (Haliaeetus leucocephalus; Elliott et al., 2009) and Herring Gull (Larus argentatus; Sørmo et al., 2011), have related variation in dietary ecology, through analysis of carbon and nitrogen SIs, to variation in POP exposure. Until now, however, it has not been investigated whether and how dietary ecology independently, or in combination with other biological or spatial factors, may influence intra- and interspecific POP exposure in predatory birds. In addition, SI half-lives in the tissues used in above-mentioned studies (≤ 18 days for blood plasma, liver and muscle; Boecklen et al., 2011) are much shorter than average POP half-lives (≤ 400 days; Fisk et al., 2001), and may have possibly resulted in less accurate associations.

In the present study, we performed a large-scale field sampling of fully-grown predatory bird nestlings, targeted at maximising ecological (dietary carbon source and trophic level) and spatial variation (local habitat and regional nest location), while minimising confounding biological factors, such as migration, age and reproductive status. During three breeding seasons (2008–2010), we sampled body feathers from nestlings of three ecologically distinct predatory bird species in subarctic Norway: Northern Goshawk (Accipiter gentilis), White-tailed Eagle (Haliaeetus albicilla) and Golden Eagle (Aquila chrysaetos). To the best of our knowledge, the present study performs for the first time the combined analysis of nestling body feathers for POPs and SIs, thus integrating the SI incorporation and POP accumulation over the larger part of the nestling stage: body feather growth is initiated at day 27 and is still ongoing at day 60 upon sampling (Golden Eagle observations; Watson, 2010). We aimed to investigate whether and how ecological (dietary carbon source, trophic level), biological (sex, body condition) and spatial factors (local habitat) independently, or in combination, influenced intraspecific variation in nestling exposure to polychlorinated biphenyl 153 (CB 153), dichlorodiphenyldichloroethylene (p,p′-DDE), polybrominated diphenyl ether 47 (BDE 47) and hexachlorobenzene (HCB). In addition, we aimed at investigating how the feeding ecology (dietary carbon source, trophic level) and regional nest location may have influenced interspecific exposure.

Section snippets

Field sampling

The sampling area (68.46–70.59 °N; 15.62–26.10 °E) was situated within the two northernmost counties of Norway, Troms and Finnmark (Fig. 1; Table 1). During the breeding seasons in 2008, 2009 and 2010, we have sampled nestlings from three predatory bird species, each resident in a typical ecosystem in subarctic Norway: White-tailed Eagle (marine ecosystem), Northern Goshawk (woodland ecosystem) and Golden Eagle (mountainous ecosystem). White-tailed Eagle and Northern Goshawk resided

Intraspecific variation

In Northern Goshawk, δ¹⁵N differed significantly between local habitats (F_1,63 = 6.17; P = 0.02), with coastal nestlings being + 1.40‰ enriched in ¹⁵N compared to those inland (P_adj = 0.02). No inter-annual (F_2,63 = 1.14; P = 0.33) nor sex differences (F_1,63 = 1.33; P = 0.25) in δ¹⁵N were observed. In contrast, δ¹³C differed significantly among sampling years (F_2,63 = 9.30; P < 0.01), but not between local habitats (F_1,63 = 0.01; P = 0.92) or sexes (F_1,63 = 0.06; P = 0.80). Northern Goshawk nestlings sampled in 2009 and

Discussion

In the present study, the first aim was to identify biological and spatial variables that may drive the observed intraspecific variation in POP exposure. The most parsimonious LMEMs revealed that intraspecific variation in exposure was driven by a combination of factors, often different among individual compounds, and that combinations for individual compounds differed among species (Table 2). Generally, but not always significantly, ecological factors such as trophic level, local habitat, or

Conclusions

To the best of our knowledge, the present study integrated for the first time the analysis of POPs and SIs in predatory bird nestling body feathers. This novel methodology successfully identified ecological and spatial factors that may influence variation in POP exposure over the larger part of the nestling stage. Ecological factors, such as trophic level and dietary carbon source, as well as spatial factors, such as local habitat and regional nest location, contribute to explain variation in

Acknowledgements

This study was performed within the RAPTOR 2015 project (NFR project ES421785: Persistent organic pollutants and natural stress in avian top predators of northern ecosystems: potential vulnerability to environmental change). RAPTOR 2015 was supervised by J.O. Bustnes and funded by the Norwegian Research Council. We also thank the University of Antwerp and FWO Flanders for funding Eulaers, Jaspers, Covaci, Pinxten and Eens. Finally, we acknowledge Bård Bårdsen, Erik Fransen and Stefan Van Dongen

References (52)

A.L. Bond
Relationships between stable isotopes and metal contaminants in feathers are spurious and biologically uninformative
Environ Pollut
(2010)
D. Chen et al.
A global review of polybrominated diphenyl ether flame retardant contamination in birds
Environ Int
(2010)
K.H. Elliott et al.
PCBs and DDE, but not PBDEs, increase with trophic level and marine input in nestling bald eagles
Sci Total Environ
(2009)
I. Eulaers et al.
A first evaluation of the usefulness of feathers of nestling predatory birds for non-destructive biomonitoring of persistent organic pollutants
Environ Int
(2011)
I. Eulaers et al.
A comparison of non-destructive sampling strategies to assess the exposure of white-tailed eagle nestlings (Haliaeetus albicilla) to persistent organic pollutants
Sci Total Environ
(2011)
V.L.B. Jaspers et al.
Preen oil as the main source of external contamination with organic pollutants onto feathers of the common magpie (Pica pica)
Environ Int
(2008)
V.L.B. Jaspers et al.
Concentrations in bird feathers reflect regional contamination with organic pollutants
Sci Total Environ
(2009)
A.K. Johansson et al.
Temporal trends of polybrominated diphenyl ethers and hexabromocyclododecane in Swedish Peregrine Falcon (Falco peregrinus peregrinus) eggs
Environ Int
(2011)
J.B. Johnson et al.
Model selection in ecology and evolution
Trends Ecol Evol
(2004)
K.F. Leith et al.
A comparison of techniques for assessing central tendency in left-censored data using PCB and p, p′-DDE contaminant concentrations from Michigan's Bald Eagle Biosentinel Program
Chemosphere
(2010)

R.J. Letcher et al.

Exposure and effects assessment of persistent organohalogen contaminants in Arctic wildlife and fish

Sci Total Environ

(2010)

R. Lohmann et al.

Global fate of POPs: current and future research directions

Environ Pollut

(2007)

S.A. Macko et al.

Kinetic fractionation of stable nitrogen isotopes during amino-acid transamination

Geochim Cosmochim Acta

(1986)

A. Möller et al.

Polybrominated diphenyl ethers (PBDEs) and alternative brominated flame retardants in air and seawater of the European Arctic

Environ Pollut

(2011)

C. Sonne

Health effects from long-range transported contaminants in Arctic top predators: an integrated review based on studies of polar bears and relevant model species

Environ Int

(2010)

C. Sonne et al.

Relationships between organohalogen contaminants and blood plasma clinical–chemical parameters in chicks of three raptor species from Northern Norway

Ecotoxicol Environ Saf

(2010)

C. Sonne et al.

Blood plasma clinical–chemical parameters as biomarker endpoints for organohalogen contaminant exposure in Norwegian raptor nestlings

Ecotoxicol Environ Saf

(2012)

E.G. Sørmo et al.

Trophic level determines levels of brominated flame-retardants in coastal herring gulls

Ecotoxicol Environ Saf

(2011)

Y. Sun et al.

Brominated flame retardants in three terrestrial passerine birds from South China: geographical pattern and implication for potential sources

Environ Pollut

(2012)

AMAP

Arctic pollution 2011

Arctic Monitoring and Assessment Programme (AMAP), Oslo vi +

(2011)

A. Bakke

The use of DDT in Norwegian forestry. Review and present situation

Tidsskr Skogbr

(1970)

K.S. Betts

New thinking on flame retardants

Environ Health Perspect

(2008)

W.J. Boecklen et al.

On the use of stable isotopes in trophic ecology

Annu Rev Ecol Evol Syst

(2011)

R. Boonstra

Coping with changing northern environments: the role of the stress axis in birds and mammals

Integr Comp Biol

(2004)

K. Borgå et al.

Trophic magnification factors: considerations of ecology, ecosystems, and study design

Integr Environ Assess Manag

(2012)

J. Burger et al.

On developing bioindicators for human and ecological health

Environ Monit Assess

(2001)

Cited by (28)

Effects of white-tailed eagle (Haliaeetus albicilla) nestling diet on mercury exposure dynamics in Kopački rit Nature Park, Croatia
2023, Environmental Pollution
The present study assessed for the first time the magnitude and dietary ecological source of total mercury (THg) exposure in a southern population of white-tailed eagles (Haliaeetus albicilla), an apex predator species shown valuable for environmental biomonitoring. This population depends on the Kopački rit Nature Park – the most important breeding site. We assessed THg exposure, using nestling body feathers collected between 2014–2019 (n = 72), and potential dietary ecological sources, proxied by prey remains and stable isotope analysis. Results show THg concentrations vary significantly over the years, though not showing any time trend. Prey remains analysis shows nests with aquatic prey remains to exhibit higher THg concentrations (median: 7.57 μg g⁻¹ dw; min – max: 6.00–13.16 μg g⁻¹ dw) compared to those with terrestrial remains (median: 3.94 μg g⁻¹ dw; min – max: 0.28–12.04 μg g⁻¹ dw) or evidencing a mixed diet (median: 7.43 μg g⁻¹ dw; min – max: 3.38–12.04 μg g⁻¹ dw). Nests with a predominant aquatic diet show elevated lower δ¹³C and higher δ¹⁵N values, indicating agreement between both dietary approaches. The model selection reveals a combination of year and δ¹⁵N best explain the variability in feather THg concentrations. Complementing these predictors with a dietary descriptor based on prey remains results in a poorer model fit and lowered explanatory power, similar to sexing the nestlings. The observed body feather THg concentrations (median: 6.99 μg g⁻¹ dw; min − max: 0.27 − 17.16 μg g⁻¹ dw) exceeded putative biogeochemical background levels (5.00 μg g⁻¹ dw) in 71% of the nestlings, though, did not seem to exceed a threshold at which detrimental physiological effects are expected (40 μg g⁻¹ dw). Continued monitoring is warranted as the studied population is likely exposed to a larger cocktail of contaminants while resident-protected bird areas.
Long-term monitoring of exposure to toxic and essential metals and metalloids in the tawny owl (Strix aluco): Temporal trends and influence of spatial patterns
2023, Science of the Total Environment
As a result of regulatory decisions, atmospheric deposition of most toxic metals and metalloids (MEs) has decreased in Europe over the past few decades. However, little is known about how this reduction translates into exposure at higher trophic levels in the terrestrial environment where temporal trends may be spatially heterogeneous due to local current or legacy sources of emissions (e.g., industry) or long-range transport of elements (e.g., marine transport). The aim of this study was to characterize temporal and spatial trends of exposure to MEs in terrestrial food webs using a predatory bird, the tawny owl Strix aluco, as a biomonitor. Toxic (Al, As, Cd, Hg, Pb) and essential/beneficial (B, Co, Cu, Mn, Se) elemental concentrations were measured in feathers of nest-captured females from 1986 to 2016, extending a previous study published over the time-series 1986–2005 (n = 1051), in a breeding population in Norway. A drastic decline over time was shown for the toxic MEs (−97 % for Pb, −89 % for Cd, −48 % for Al, and −43 % for As) except Hg. The beneficial elements B, Mn, and Se showed oscillations but an overall decline (−86 %, −34 %, and −12 %, respectively) whereas the essentials Co and Cu did not exhibit significant trends. The distance to potential sources of contamination influenced both the spatial patterns of concentrations in owl feathers and their temporal trends. The accumulation of As, Cd, Co, Mn and Pb was overall higher in the vicinity of sites recorded as polluted, and a greater temporal decrease of As, B, and Cd concentrations was found in the areas of further distance to polluted sites. The decrease of Pb concentrations was sharper further from the coast during the 1980s than in coastal areas, while the opposite was observed for Mn. The levels of Hg and Se were higher in coastal areas, and Hg temporal trends differed according to the distance to the coast. This study highlights the valuable insights provided by long-term survey of wildlife exposure to pollutants and landscape indicators to reveal regional or local patterns and detect unexpected events, data that are crucial for regulation and conservation of ecosystem health.
The impact of climate sensitive factors on the exposure to organohalogenated contaminants in an aquatic bird exploiting both marine and freshwater habitats
2022, Science of the Total Environment
To assess how climate-sensitive factors may affect the exposure to organochlorines (OCs) and perfluoroalkyl substances (PFASs), we monitored concentrations in eggs of the common goldeneye (Bucephala clangula) over two decades (1999–2019) in central Norway. The goldeneye alternates between marine and freshwater habitats and is sensitive to climate variation, especially due to alterations in ice conditions which may affect feeding conditions. We assessed how biological factors such as diet (stable isotopes δ¹³C and δ¹⁵N), the onset of egg laying, and physical characteristics such as winter climate (North Atlantic Oscillation: NAO_w) influenced exposure. We predicted compounds to show different temporal trends depending on whether they were still in production (i.e. some PFASs) or have been banned (i.e. legacy OCs and some PFASs). Therefore, we controlled for potential temporal trends in all analyses. There were declining trends for α- and γ-hexachlorocyclohexane (HCH), oxychlordane, cis-chlordane, cis-nonachlor, p,p′-dichlorodiphenyltrichloroethane (p.p′-DDT) and less persistent polychlorinated biphenyl (PCB) congeners (e.g. PCB101). In contrast, the dominant compounds, such as p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) and persistent PCB congeners, were stable, whereas hexachlorobenzene (HCB) increased over time. Most OCs were positively related to δ¹⁵N, suggesting higher exposure in birds feeding at upper trophic levels. Chlordanes and HCB were positively associated with δ¹³C, indicating traces of marine input for these compounds, whereas the relationships to most PCBs were negative. Among PFASs, perfluorooctanesulfonamide (PFOSA) and perfluorohexane sulfonic acid (PFHxS) declined. Most PFASs were positively associated with δ¹³C, whereas there were no associations with δ¹⁵N. Egg laying date was positively associated to perfluoroheptanesulfonic acid (PFHpS), perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), suggesting that some of the PFAS load originated from the wintering locations. Although NAOw had little impact on the exposure to organohalogenated contaminants, factors sensitive to climate change, especially diet, were associated with the exposure to OHCs in goldeneyes.
Feathers as an integrated measure of organohalogen contamination, its dietary sources and corticosterone in nestlings of a terrestrial bird of prey, the northern Goshawk (Accipiter gentilis)
2022, Science of the Total Environment
In this study, we evaluated the suitability of body feathers, preen oil and plasma for estimation of organohalogen compound (OHC) exposure in northern goshawk Accipiter gentilis nestlings (n = 37; 14 nests). In addition, body feathers received further examination concerning their potential to provide an integrated assessment of (1) OHC exposure, (2) its dietary sources (carbon sources and trophic position) and (3) adrenal gland response (corticosterone). While tetrabromobisphenol A was not detected in any sample, the presence of polychlorinated biphenyls, organochlorine pesticides, polybrominated diphenyl ethers and hexabromocyclododecane in body feathers (median: 23, 19, 1.6 and 3.5 ng g⁻¹ respectively), plasma (median: 7.5, 6.2, 0.50 and 1.0 ng g⁻¹ ww, respectively) and preen oil (median: 750, 600, 18 and 9.57 ng g⁻¹ ww, respectively) suggests analytical suitability for biomonitoring of major OHCs in the three matrices. Furthermore, strong and significant associations (0.20 ≤ R² ≤ 0.98; all P < 0.05) among the OHC concentrations in all three tissues showed that body feathers and preen oil reliably reflect circulating plasma OHC levels. Of the dietary proxies, δ¹³C (carbon source) was the most suitable predictor for variation in feather OHCs concentrations, while no significant relationships between body feather OHCs and δ¹⁵N (trophic position) were found. Finally, body feather corticosterone concentrations were not related to variation in OHC concentrations. This is the first study to evaluate feathers of a terrestrial bird of prey as an integrated non-destructive tool to jointly assess nestling ecophysiology and ecotoxicology.
Ecological and spatial variations of legacy and emerging contaminants in white-tailed sea eagles from Germany: Implications for prioritisation and future risk management
2022, Environment International
The increasing use of chemicals in the European Union (EU) has resulted in environmental emissions and wildlife exposures. For approving a chemical within the EU, producers need to conduct an environmental risk assessment, which typically relies on data generated under laboratory conditions without considering the ecological and landscape context. To address this gap and add information on emerging contaminants and chemical mixtures, we analysed 30 livers of white-tailed sea eagles (Haliaeetus albicilla) from northern Germany with high resolution-mass spectrometry coupled to liquid and gas chromatography for the identification of >2400 contaminants. We then modelled the influence of trophic position (δ¹⁵N), habitat (δ¹³C) and landscape on chemical residues and screened for persistent, bioaccumulative and toxic (PBT) properties using an in silico model to unravel mismatches between predicted PBT properties and observed exposures. Despite having generally low PBT scores, most detected contaminants were medicinal products with oxfendazole and salicylamide being most frequent. Chemicals of the Stockholm Convention such as 4,4′-DDE and PCBs were present in all samples below toxicity thresholds. Among PFAS, especially PFOS showed elevated concentrations compared to other studies. In contrast, PFCA levels were low and increased with δ¹⁵N, which indicated an increase with preying on piscivorous species. Among plant protection products, spiroxamine and simazine were frequently detected with increasing concentrations in agricultural landscapes. The in silico model has proven to be reliable for predicting PBT properties for most chemicals. However, chemical exposures in apex predators are complex and do not solely rely on intrinsic chemical properties but also on other factors such as ecology and landscape. We therefore recommend that ecological contexts, mixture toxicities, and chemical monitoring data should be more frequently considered in regulatory risk assessments, e.g. in a weight of evidence approach, to trigger risk management measures before adverse effects in individuals or populations start to manifest.
Non-invasive biomonitoring of organic pollutants using feather samples in feral pigeons (Columba livia domestica)
2020, Environmental Pollution
A large portion of organic pollutants (OPs) represent a potential hazard to humans and living beings due to their toxic properties. For several years, birds have been used as biomonitor species of environmental pollution. Polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated biphenyl ethers (PBDEs), organophosphate pesticides (OPPs), polycyclic aromatic hydrocarbons (PAHs) and pyrethroids (PYRs) were assessed in body feather samples of 71 feral pigeons (Columba livia domestica) collected from Asturias and Galicia (NW Spain). The percentage of detection for all chemical groups were above 90% in studied birds. The general pattern was dominated by PAHs (mean value ± standard deviation (SD) 32 ± 15 ng/g) followed by OCPs (3.8 ± 1.1 ng/g), PYRs (3.4 ± 3.8 ng/g), PCBs (1.6 ± 1.0 ng/g), OPPs (1.3 ± 0.70 ng/g) and PBDEs (0.80 ± 0.30 ng/g). Significant differences were observed between age, location and gender suggesting different sources of exposure and accumulation pathways.

View all citing articles on Scopus

View full text

Ecological and spatial factors drive intra- and interspecific variation in exposure of subarctic predatory bird nestlings to persistent organic pollutants

Highlights

Abstract

Introduction

Section snippets

Field sampling

Intraspecific variation

Discussion

Conclusions

Acknowledgements

Environ Pollut

Environ Int

Sci Total Environ

Environ Int

Sci Total Environ

Environ Int

Sci Total Environ

Environ Int

Trends Ecol Evol

Chemosphere

Sci Total Environ

Environ Pollut

Geochim Cosmochim Acta

Environ Pollut

Environ Int

Ecotoxicol Environ Saf

Ecotoxicol Environ Saf

Ecotoxicol Environ Saf

Environ Pollut

Arctic pollution 2011

Arctic Monitoring and Assessment Programme (AMAP), Oslo vi +

The use of DDT in Norwegian forestry. Review and present situation

Tidsskr Skogbr

New thinking on flame retardants

Environ Health Perspect

On the use of stable isotopes in trophic ecology

Annu Rev Ecol Evol Syst

Coping with changing northern environments: the role of the stress axis in birds and mammals

Integr Comp Biol

Trophic magnification factors: considerations of ecology, ecosystems, and study design

Integr Environ Assess Manag

On developing bioindicators for human and ecological health

Environ Monit Assess