Interspecies and spatial trends in polycyclic aromatic hydrocarbons (PAHs) in Atlantic and Mediterranean pelagic seabirds

PAHs were analyzed in the liver of 5 species of pelagic seabirds (Procellariiformes) from the northeast Atlantic and the Mediterranean. The main objective was to assess the trophic and geographic trends of PAHs in seabirds to evaluate their suitability as bioindicators of chronic marine pollution by these compounds. Although higher levels of PAHs have been described in the Mediterranean compared to other oceanic regions, we did not find significant spatial patterns and observed only minor effects of the geographic origin on seabird PAHs. However, we found significant higher PAH levels in petrel compared to shearwater species, which could be related to differences in their exploitation of mesopelagic and epipelagic resources, respectively, and the vertical dynamic of PAHs in the water column. Overall, although this study enhances the need of multi-species approaches to show a more comprehensive evaluation of marine pollution, seabirds emerged as poor indicators of pelagic chronic PAH levels.     

Organochlorine contaminants in seven species of Arctic seabirds from northern Baffin Bay

Organochlorine contaminants (OCs) were determined in liver and fat of seven species of seabirds (Alle alle, Uria lomvia, Cepphus grylle, Rissa tridactyla, Pagophila eburnea, Larus hyperboreus, and Fulmaris glacialis) collected in May/June 1998 from the Northwater Polynya in northern Baffin Bay. OC concentrations ranged over an order of magnitude between seabird species and OC groups, with PCBs having the highest concentrations followed by DDT, chlordane, HCH and ClBz. Positive relationships between delta15N (estimator of trophic level) and OC concentrations (lipid basis) were found for all OC groups, showing that trophic position and biomagnification significantly influence OC concentrations in Arctic seabirds. Concentrations of a number of OCs in particular species (e.g., HCH in P. eburnean) were lower than expected based on delta15N and was attributed to biotransformation. P. eburnea and F. glacialis, which scavenge, and R. tridactyla, which migrate from the south, were consistently above the delta15N-OC regression providing evidence that these variables can elevate OC concentrations. Stable isotope measurements in muscle may not be suitable for identifying past scavenging events by seabirds. OC relative proportions were related to trophic position and phylogeny, showing that OC biotransformation varies between seabird groups. Trophic level, migration, scavenging and biotransformation all play important roles in the OCs found in Arctic seabirds.     

Organochlorine contaminant and stable isotope profiles in Arctic fox (Alopex lagopus) from the Alaskan and Canadian Arctic

Arctic fox (Alopex lagopus) is a circumpolar species distributed across northern Canada and Alaska. Arctic fox muscle and liver were collected at Barrow, AK, USA (n=18), Holman, NT, Canada (n=20), and Arviat, NU, Canada (n=20) to elucidate the feeding ecology of this species and relate these findings to body residue patterns of organochlorine contaminants (OCs). Stable carbon (delta 13C) and nitrogen (delta 15N) isotope analyses of Arctic fox muscle indicated that trophic position (estimated by delta 15N) is positively correlated with increasing delta 13C values, suggesting that Arctic fox with a predominantly marine-based foraging strategy occupy a higher trophic level than individuals mostly feeding from a terrestrial-based carbon source. At all sites, the rank order for OC groups in muscle was polychlorinated biphenyls (Sigma PCB) > chlordane-related compounds (Sigma CHLOR) > hexachlorocyclohexane (Sigma HCH) > total toxaphene (TOX) > or = chlorobenzenes (Sigma ClBz) > DDT-related isomers (Sigma DDT). In liver, Sigma CHLOR was the most abundant OC group, followed by Sigma PCB > TOX > Sigma HCH > Sigma ClBz > Sigma DDT. The most abundant OC analytes detected from Arctic fox muscle and liver were oxychlordane, PCB-153, and PCB-180. The comparison of delta 15N with OC concentrations indicated that relative trophic position might not accurately predict OC bioaccumulation in Arctic fox. The bioaccumulation pattern of OCs in the Arctic fox is similar to the polar bear. While Sigma PCB concentrations were highly variable, concentrations in the Arctic fox were generally below those associated with the toxicological endpoints for adverse effects on mammalian reproduction. Further research is required to properly elucidate the potential health impacts to this species from exposure to OCs.     

Levels and distribution of organophosphorus flame retardants and plasticizers in fishes from Manila Bay, the Philippines

Organophosphorus compounds (OPCs) and stable isotope ratios (δ¹³C and δ¹⁵N) were determined in 58 fishes belonging to 20 species collected from Manila Bay, the Philippines. OPCs were detected in most of the samples and found up to μg/g lw (lipid weight) level, suggesting their ubiquitous presence in the coastal marine environment of the Philippines. Higher levels (>1000 ng/g lw) of total OPCs were determined in yellowstriped goatfish, silver sillago, tripletail wrasse and bumpnose trevally indicates either their active uptake from ambient water or lower metabolic capacity of these species. Levels of triphenyl phosphate (TPhP) in demersal species showed a positive correlation with δ¹⁵N, indicating that TPhP was adsorbed onto the particle, settled down to the bottom sediment and accumulated through the benthic food web rather than the pelagic. Estimated dietary intake of OPCs in Manila Bay fishes were four to five orders of magnitude lower than the proposed reference dose (RfD).     

Relationships between reproductive performance and organochlorine contaminants in great black-backed gulls (Larus marinus)

The great black-backed gull Larus marinus is a top predator in subarctic and temperate marine ecosystems, and the aim of this study was to investigate if organochlorines (OCs) were related to reproductive performance in this species at the subarctic parts of the Norwegian Coast. We measured blood levels of various OCs in 53 breeding birds. The OC levels were relatively low compared to levels found in nearby arctic areas. In females, however, there was a significant positive relationship between blood concentrations of OCs, especially hexachlorobenzene (HCB) and, p,p'-dichlorodiphenyldichloroethylene (DDE), and egg laying date, and a positive relationship between the probability of nest predation and blood concentration of beta-hexachlorocyclohexane (beta-HCH), oxychlordane, and DDE. In females with high levels of OCs, especially persistent polychlorinated biphenyls (PCBs), there was also a decline in egg volume as egg laying progressed; i.e. the second and third laid egg were relatively smaller, compared to females with low OC levels. No relationships between reproductive parameters and OC levels were found in males.     

Effects of environmental exposure and diet on levels of persistent organic pollutants (POPs) in eggs of a top predator in the North Atlantic in 1980 and 2008

Concentrations of POPs in Great skua eggs from Shetland are among the highest in North Atlantic seabirds, with up to 11,600 μg/kg (ww) DDE and up to 17,900 μg/kg ww ∑PCB. Concentrations of legacy POPs were significantly lower in 2008 than 1980. Decreases were greatest for least persistent compounds. Median ∑PBDEs increased from 99 μg/kg ww in 1980 to 173 μg/kg ww in 2008. There were changes in Great skua breeding season diet, with more adult Herring and Mackerel and less Sandeel. These changes increase exposure to POPs, since Herring and Mackerel accumulate more POPs than Sandeels. In both years, eggs with higher δ¹⁵N had higher POP concentrations. In 1980, birds feeding more on demersal discard fish from trawl fisheries and less on Sandeels, had higher POP levels in eggs. In 2008, individuals feeding more on Herring and Mackerel, and less on discards, had higher POP levels in eggs.     

The Sea Around Us Project: documenting and communicating global fisheries impacts on marine ecosystems

The Sea Around Us Project, initiated by the Pew Charitable Trusts in Philadelphia, PA, and located at the Fisheries Centre, University of British Columbia, Vancouver, Canada, started in mid 1999. Its goal was (and still is) to investigate the impact of fisheries on marine ecosystems and to propose policies to mitigate these impacts. Although conceived as a global activity, the project first emphasized the data-rich North Atlantic as a test bed for developing its approaches, which rely on mapping of catch data and indicators of ecosystem health derived from the analysis of long catch time series data. Initial achievements included mapping the decline, throughout the North Atlantic basin, of high-trophic level fishes from 1900 to the present and the presentation of compelling evidence of change in the functioning of the North Atlantic ecosystems, summarized in a 2003 book. The Central and South Atlantic were the next basins to be tackled, with emphasis on the distant-water fleet off West Africa, culminating in a major conference in Dakar, Senegal, in 2002. The project then emphasized the North Pacific, Antarctica, and marine mammals and the multiplicity of tropical Indo-Pacific fisheries before it turned completely global, with all our major analyses and reports (e.g., on the interactions between marine mammals and fisheries, on fuel consumption by fleets, on the catches of small-scale fisheries, on subsidies to fisheries) being based on global studies. Broadly, the work of the project is aimed at a reappraisal of fisheries, from the benign activity that many interested people still perceive them to be, to a realization that they have become the driver for massive loss of biodiversity in the ocean. Moreover, the emphasis on global estimates (rather than local estimates of dubious generality) has allowed the project to contribute to various global initiatives (e.g., developing the Marine Trophic Index for the Convention on Biological Diversity, quantifying marine ecosystem services for the Millennium Ecosystem Assessment), that is, activities that we expect to increase and for which we invite collaboration from academia and environmental nongovernmental organizations.     

Examination of the bioaccumulation of halogenated dimethyl bipyrroles in an Arctic marine food web using stable nitrogen isotope analysis.

Concentrations of four possibly naturally produced organohalogens--1,1'-dimethyl-3,3',4-tribromo-4,5,5'-trichloro-2,2'-bipyrrole (DBP-Br3Cl3), 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2), 1,1'-dimethyl-3,3',4,4',5-pentabromo-5'-chloro-2,2'-bipyrrole (DBP-Br5Cl) and 1,1'-dimethyl-3,3',4,4',5,5'-hexabromo-2,2'-bipyrrole (DBP-Br6)--were quantitated and the extent of their magnification through an entire Arctic marine food web [measured as integrated trophic magnification factors (TMFs)] were calculated. The food web consisted of three zooplankton species (Calanus hyperboreus, Mysis oculata, and Sagitta sp.), one fish species [Arctic cod (Boreogadus saida)], four seabird species [dovekie (Alle alle), black guillemot (Cepphus grylle), black-legged kittiwake (Rissa tridactyla), and glaucous gull (Larus hyperboreus)], and one marine mammal species [ringed seal (Phoca hispida)]. Trophic levels in the food web were calculated from ratios of stable isotopes of nitrogen (15N/14N). All halogenated dimethyl bipyrrole (HDBP) congeners were found to significantly (P<0.02) biomagnify, or increase in concentration with trophic level in the invertebrate--fish--seabird food web. DBP-Br4Cl2 (TMF= 14.6) was found to biomagnify to a greater extent than DBP-Br3Cl3 (TMF = 5.2), DBP-Br5Cl (TMF = 6.9), or DBP-Br6 (TMF = 7.0), even though the Kow of DBP-Br4CI2 was predicted to be lower than those of DBP-Br5Cl and DBP-Br6. None of the four HDBP congeners in ringed seals followed the general trend of increasing concentration with trophic level, which was possibly due to an ability of the seals to metabolize HDBPs.     

Temporal and biogeographic comparisons of PCBs and persistent organochlorine pollutants in the blubber of fin whales from eastern Canada in 1971-1991

Concentrations of PCB congeners and organochlorine (OC) pesticides were studied in archived fin whale (Balaenoptera physalus) blubber samples collected in 1971-1972 from Newfoundland (Nfld) and Nova Scotia (NS) with the objective of obtaining a historical perspective on contaminant levels and proportions at a time when many persistent OCs were still in use. Concentrations of sigmaPCBs and sigmaDDTs in the blubber of 17 fin whales from historical whaling stations in 1971-1972 were generally in agreement with previously reported values for fin whales from Atlantic Canada. Although some differences in sex and body length (age) distribution of samples occurred, significant differences were detected in the concentrations and patterns of PCBs, DDTs and chlordanes in whales from Nfld and NS, supporting ecological evidence that whales from these regions represent relatively separate stocks. Temporal and geographical variations were examined by comparing data to those reported for fin whales from the St Lawrence Estuary (StL) in 1991 by Gauthier et al. (1997a). Significantly higher levels of sigmaDDT, sigmaCHL and HCB were found in the NS (1971-1972) stock compared with the StL (1991) animals, and in HCB between the Nfld stock (1971-1972) and the StL (1991) animals, as well as higher p,p'-DDE/sigmaDDT and lower p,p'-DDT/sigmaDDT ratios in the 1991 whales suggesting that temporal trends in these whales between the 1970s and 1990s were consistent with those in other marine mammals in Atlantic Canada. Evidence also suggests that geographical variations in patterns may occur for individuals from two relatively distinct stocks of fin whales in Atlantic Canada (NS, Nfld) and perhaps for one population (StL) related to, but recognisably different from the NS stock.     

New Perspectives on Marine Biodiversity

Marine and terrestrial ecosystems are so fundamentally different in some aspects that many of the issues concerning biodiversity cannot be interpreted using a single theory of common application to all ecosystems. Their limitation is evident when it comes to highly biodiverse and interconnected marine ecosystems such as coral reefs. Trophic links are a major factor, but space, breeding, shelter from predators, environmental cues, behavior ingrained in genotypes, genetic variability, mutations, and connectivity of marine critical habitats are also important. The importance of the connectivity of habitats such as coral reefs, seagrasses, and mangrove in biodiversity preservation should be recognized. Migratory species require corridors for gene flow and that influences diversity. The existing theories do not address the biodiversity issues related to life in the abyssal plains and deep sea trenches and the challenge posed by climate change. An accurate understanding of marine biodiversity requires comprehensive knowledge of ecological interrelationships and new perspectives that reflect the reality of global environmental change.     

Follow-up trends of parasite community alteration in a marine fish after the Prestige oil-spill: shifting baselines?

This study evaluates the follow-up trends in the composition and structure of the parasite communities in the marine sparid Boops boops after the Prestige oil-spill. A total of 400 fish comprising 11 seasonal samples was analyzed from three impacted localities on the Atlantic coast of Spain. A large number of parasite species was recovered only after the spill thus suggesting a substantial alteration of the marine food webs. Post-spill communities exhibited higher richness and abundance due to the significant changes in the abundance of the common species, the latter indicating accelerated parasite transmission rates. Multivariate analyses at two nested scales detected a directional trend in parasite community succession towards the pre-spill situation, however, with no full support for community recovery. The state of parasite communities in 2005-2006 may provide the new baseline data which can serve as a framework for quantifying the impact of potential future spills in the region.     

Organochlorines, brominated flame retardants and mercury levels in six seabird species from the Gulf of St. Lawrence (Canada): Relationships with feeding ecology, migration and molt

Concentrations of organochlorines (OCs), brominated flame retardants (BFRs) and mercury (Hg) were measured in eggs of six seabird species breeding in the Gulf of St. Lawrence, Canada. Stable nitrogen (δ¹⁵N) and carbon (δ¹³C) isotopes were used as ecological tracers to measure trophic level and connectivity with benthos, respectively. Concentrations, patterns as well as ecological tracers varied significantly between species. The sum of polychlorinated biphenyls (ΣPCBs) was the most important group measured in all seabird species based on concentration followed generally by the sum of chlorinated pesticides (ΣCPs), the sum of brominated flame retardants (ΣBFRs) and finally total Hg (THg). ΣPCBs, ΣCPs and ΣBFRs increased with trophic level, whereas THg did not. Only ΣBFRs increased with a higher connectivity with the benthos. Seabird species resident to the Great Lakes-St. Lawrence ecosystem showed higher Hg and BFR levels than migratory species. Molt patterns were used to explain variations of contaminant levels.     

Monthly variations in nitrogen isotopes of ammonium and nitrate in wet deposition at Guangzhou,south China

Monthly nitrogen isotopes of ammonium and nitrate in wet deposition in the city of Guangzhou, and the causes of their variability, are reported in this paper. Nitrate δ¹⁵N showed nearly constant values around zero in the dry season (October to April), but oscillating values from negative to positive in the rainy season (May to September). By contrast, ammonium δ¹⁵N displayed lower values during the rainy season than in the dry season. The rural area north of the city was considered as the prominent source of ammonium and nitrate in spring and early summer (May and June), as suggested by their concurrent negative isotopic trends and higher NH₄⁺/NO₃^? ratios. From July to September, different dominating sources from the city, i.e., fossil fuel combustion for nitrate, and sewage and waste emission for ammonium, caused disparate δ¹⁵N trends of the two species, showing positive nitrate δ¹⁵N, but still negative ammonium δ¹⁵N. During the cool dry season, the high values of ammonium δ¹⁵N and concurrently low NH₄⁺/NO₃^? ratios suggested the decrease in NH₃ volatilization and relatively important thermogenic origin of ammonium, but the intermediate nitrate δ¹⁵N values around zero may be a result of a balanced emission of NO_x from the city and the rural areas. The isotopic effects of chemical conversion of NO_x to nitrate and washout of nitrate were ruled out as significant causes of nitrate δ¹⁵N variability, but ammonium washout, during which ¹⁵N is assumed to be preferentially removed, may partly contribute to the ammonium δ¹⁵N variability.     

Halogenated organic contaminants and mercury in northern fulmars (Fulmarus glacialis): levels, relationships to dietary descriptors and blood to liver comparison

The northern fulmar (Fulmarus glacialis) is an interesting candidate for the study of patterns and levels of halogenated organic contaminants (HOCs) since they accumulate high levels of certain HOCs. In the present study we characterized a suite of established and novel HOCs in northern fulmars breeding on Bj?rn?ya in the Norwegian Arctic. A comparison between blood and liver HOC levels was made, and the levels were related to the ratios of heavier to lighter stable isotopes of nitrogen (15)N/(14)N (delta(15)N) and carbon (13)C/(12)C (delta(13)C) in muscle. A significant difference in congener patterns between blood and liver was found. The delta(13)C was not related to HOCs, neither in liver nor in blood. Weak correlations were found between delta(15)N and liver HOC levels. The 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) in northern fulmars were well above thresholds for reproductive effects in seabirds.     

Levels and distribution of organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in sediments and biota from the Danube Delta, Romania

Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and analogues, hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB), were measured in sediments and biota (invertebrates, 11 fish species and cormorant tissues) collected in 2001 from the Danube Delta, the biggest European wetland. DDTs were the predominant pollutants in all samples. A high variability in the concentrations of pollutants within the same species was observed and this was related to sampling location, age, length and sex. DDTs were also the main organohalogenated contaminants in cormorant muscle and liver, followed by PCBs, HCHs, HCB and PBDEs. The present levels of DDTs in cormorant tissues are lower than levels measured in cormorant eggs sampled from the Danube Delta in 1982 and 1997, respectively. The variance of delta15N for herbivores was much greater than for carnivores, while carp and bream showed higher delta15N signatures than expected, probably due to a higher dietary proportion of benthos, typically more delta15N enriched relative to pelagic biota.     

Relationships between stable isotopes and metal contaminants in feathers are spurious and biologically uninformative

Stable isotopes of carbon (δ¹³C) and nitrogen (δ¹⁵N) are used frequently in ecotoxicological investigations of birds to relate contaminant levels to trophic position (δ¹⁵N) or foraging location (δ¹³C) and many researchers using avian feathers in such investigations use δ¹³C or δ¹⁵N as a predictor of contaminant concentrations. Contaminants, especially mercury, however, are integrated into feathers over different time periods than are stable isotopes, resulting in spurious relationships that have no biological meaning. I show the fundamental principles behind the conclusion that relating δ¹³C or δ¹⁵N to contaminant concentrations in feathers is not appropriate in light of the number of recent studies that have employed this approach, and make recommendations for those wishing to investigate the relationship between contaminants and stable isotope ratios.     

Bioaccumulation of per- and polyfluorinated alkyl substances (PFAS) in selected species from the Barents Sea food web

The present study reports concentrations and biomagnification potential of per- and polyfluorinated alkyl substances (PFAS) in species from the Barents Sea food web. The examined species included sea ice amphipod (Gammarus wilkitzkii), polar cod (Boreogadus saida), black guillemot (Cepphus grylle) and glaucous gull (Larus hyperboreus). These were analyzed for PFAS, polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs) and polybrominated diphenyl ethers (PBDEs). Perfluorooctane sulfonate (PFOS) was the predominant of the detected PFAS. Trophic levels and food web transfer of PFAS were determined using stable nitrogen isotopes (delta(15)N). No correlation was found between PFOS concentrations and trophic level within species. However, a non-linear relationship was established when the entire food web was analyzed. Biomagnification factors displayed values >1 for perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), PFOS and SigmaPFAS(7). Multivariate analyses showed that the degree of trophic transfer of PFAS is similar to that of PCB, DDT and PBDE, despite their accumulation through different pathways.     

Concentrations of carbonaceous species in particles at Seoul and Cheju in Korea

Concentrations of elemental carbon (EC) and organic carbon (OC) in particles at Seoul and Cheju Island, Korea were observed in 1994. PM₁₀ and PM_2.5 were collected by a modified SCAQS (Southern California Air Quality Study) sampler from Seoul during June 1994 and PM_2.5 were collected by a low-volume sampler at Cheju Island during July and August 1994. The selective thermal oxidation method with MnO₂ catalyst was used for analysis. The EC concentrations from Seoul were higher than those at Los Angeles, USA during the SCAQS study while the OC concentrations were comparable to those during the SCAQS study. At Cheju Island, the OC concentrations were higher than those at other clean areas in the world but the EC concentrations were lower than or comparable to those at other clean areas in the world. The OC to EC ratios of Seoul suggest that the carbonaceous species are mostly from primary emission sources. In Cheju, during July 1994 air pollutant levels were high and it was suggested that atmospheric transformation/transport of organics and biogenic emissions were main sources of carbonaceous species in particles. The carbonaceous species levels were low during August 1994 and it was suggested that the levels could be considered as marine background concentrations in the region during summer.     

Profile of persistent chlorinated contaminants,including selected chiral compounds,in wolverine (Gulo gulo) livers from the Canadian Arctic

Wolverines (Gulo gulo) are circumpolar omnivores that live throughout the alpine and arctic tundra ecosystem. Wolverine livers were collected at Kugluktuk (Coppermine), NU (n=12) in the western Canadian Arctic to report, for the first time, the residue patterns of persistent organochlorine contaminants (OCs) in this species. The enantiomer fractions (EFs) of several chiral OCs, including PCB atropisomers, in wolverines were also determined. Results were compared to OC concentrations and EFs of chiral contaminants in arctic fox (Alopex lagopus) from Ulukhaqtuuq (Holman), NT (n=20); a closely related species that scavenges the marine and terrestrial arctic environment. The rank order of hepatic concentrations for sum ( summation operator ) OC groups in wolverines were polychlorinated biphenyls ( summation operator PCB)>chlordane-related components ( summation operator CHLOR)>DDT-related compounds ( summation operator DDT)>hexachlorocyclohexane isomers ( summation operator HCHs). The most abundant OC analytes detected in wolverine liver were PCB-153, PCB-180, and oxychlordane (OXY). Wolverine age and gender did not influence OC concentrations, which were comparable to lipid-normalized values in arctic fox. The EFs of several chiral OCs (alpha-HCH, cis- and trans-chlordane, OXY, heptachlor exo-epoxide) and PCB atropisomers (PCB-136, 149) were nonracemic in arctic fox and wolverine liver and similar to those previously calculated in arctic fox and polar bears from Iceland and the Canadian Arctic. Results suggest that these species have similar ability to biotransform OCs. As well, contaminant profiles suggest that terrestrial mammals do not represent the major source of OC exposure to wolverines and that wolverines are scavenging more contaminated prey items, such as marine mammals. While summation operator PCB did not exceed the concentrations associated with mammalian reproductive impairment, future research is required to properly evaluate the potential affect of other OCs on the overall health of wolverines.     

The deep-sea as a final global sink of semivolatile persistent organic pollutants? Part I: PCBs in surface and deep-sea dwelling fish of the north and south Atlantic and the Monterey Bay Canyon (California)

The understanding of the global environmental multiphase distribution of persistent organic pollutants (POPs) as a result of the physico-chemical properties of the respective compounds is well established. We have analysed the results of a vertical transport of POPs from upper water layers (0-200 m) to the deepwater region (> 800 m) in terms of the contamination of the biophase in both water layers. The contents of persistent organochlorine compounds like polychlorinated biphenyls (PCBs) in fish living in the upper water layers of the North Atlantic and the South Atlantic, and at the continental shelf of California (Marine Sanctuary Monterey Bay and its deep-sea Canyon) are compared to the levels in deep-sea or bottom dwelling fish within the same geographic area. The deep-sea biota show significantly higher burdens as compared to surface-living species of the same region. There are also indications for recycling processes of POPs--in this case the PCBs--in the biophase of the abyss as well. It can be concluded that the bio- and geo phase of the deep-sea may act similarly as the upper horizons of forest and grasslands on the continents as an ultimate global sink for POPs in the marine environment.