Legacy and emerging organic contaminants: Levels and profiles in top predator fish from the western Indian Ocean in relation to their trophic ecology

International audienceTuna and billfish are large pelagic fish of ecological importance in open oceans. As top predators with a long lifespan, they are prone to exposure to various contaminants such as persistent organic pollutants (POPs) and contaminants of emerging concern. In this study, three pollutant families were investigated, including polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and perfluoroalkyl substances (PFASs), including perfluorooctane sulfonate (PFOS) and perfluorocarboxylic acids (PFCAs). Contamination was investigated in individuals from three tropical tuna species, namely bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis) and yellowfin (Thunnusalbacares) tunas and the billfish swordfish (Xiphias gladius), collected from various areas of the western Indian Ocean (WIO) in 2013-2014. Contamination levels and profiles were examined in fish muscle, together with biological parameters (fish length / age, sex, lipid content) and ecological tracers (carbon and nitrogen stable isotopes). POP levels were low in all species in comparison to other locations worldwide, revealing a low impact of anthropogenic organic contaminants in the WIO. A predominance of OCPs (especially DDTs) versus PCBs was highlighted in all species; PFASs were predominant over chlorinated POPs in tunas. Among the studied PFASs, long-chain PFCAs were found to prevail over PFOS in all species. Organic contaminant profiles differed across species according to their foraging habitat; swordfish and bigeye tuna, which both feed in deep oceanic layers, showed similarities in their contaminant profiles. Geographically, the distinct DDT profiles of fish from the Mozambique Channel suggested an exposure to different DDT sources, in line with regional use of this insecticide and coupled with an extended residence time of fish in the Channel. To our knowledge, the data presented here are among the first obtained for legacy and emerging organic contaminants in various species of large pelagic predators from the WIO

Legacy and emerging organic contaminants: levels and profiles in top predator fish from the western Indian Ocean in relation to their trophic ecology

Tuna and billfish are large pelagic fish of ecological importance in open oceans. As top predators with a long lifespan, they are prone to exposure to various contaminants such as persistent organic pollutants (POPs) and contaminants of emerging concern. In this study, three pollutant families were investigated, including polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and perfluoroalkyl substances (PFASs), including perfluorooctane sulfonate (PFOS) and perfluorocarboxylic acids (PFCAs). Contamination was investigated in individuals from three tropical tuna species, namely bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis) and yellowfin (Thunnus albacares) tunas and the billfish swordfish (Xiphias gladius), collected from various areas of the western Indian Ocean (WIO) in 2013-2014. Contamination levels and profiles were examined in fish muscle, together with biological parameters (fish length / age, sex, lipid content) and ecological tracers (carbon and nitrogen stable isotopes). POP levels were low in all species in comparison to other locations worldwide, revealing a low impact of anthropogenic organic contaminants in the WIO. A predominance of OCPs (especially DDTs) versus PCBs was highlighted in all species; PFASs were predominant over chlorinated POPs in tunas. Among the studied PFASs, long-chain PFCAs were found to prevail over PFOS in all species. Organic contaminant profiles differed across species according to their foraging habitat; swordfish and bigeye tuna, which both feed in deep oceanic layers, showed similarities in their contaminant profiles. Geographically, the distinct DDT profiles of fish from the Mozambique Channel suggested an exposure to different DDT sources, in line with regional use of this insecticide and coupled with an extended residence time of fish in the Channel. To our knowledge, the data presented here are among the first obtained for legacy and emerging organic contaminants in various species of large pelagic predators from the WIO

Legacy and emerging organic contaminants: Levels and profiles in top predator fish from the western Indian Ocean in relation to their trophic ecology

International audienceTuna and billfish are large pelagic fish of ecological importance in open oceans. As top predators with a long lifespan, they are prone to exposure to various contaminants such as persistent organic pollutants (POPs) and contaminants of emerging concern. In this study, three pollutant families were investigated, including polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and perfluoroalkyl substances (PFASs), including perfluorooctane sulfonate (PFOS) and perfluorocarboxylic acids (PFCAs). Contamination was investigated in individuals from three tropical tuna species, namely bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis) and yellowfin (Thunnusalbacares) tunas and the billfish swordfish (Xiphias gladius), collected from various areas of the western Indian Ocean (WIO) in 2013-2014. Contamination levels and profiles were examined in fish muscle, together with biological parameters (fish length / age, sex, lipid content) and ecological tracers (carbon and nitrogen stable isotopes). POP levels were low in all species in comparison to other locations worldwide, revealing a low impact of anthropogenic organic contaminants in the WIO. A predominance of OCPs (especially DDTs) versus PCBs was highlighted in all species; PFASs were predominant over chlorinated POPs in tunas. Among the studied PFASs, long-chain PFCAs were found to prevail over PFOS in all species. Organic contaminant profiles differed across species according to their foraging habitat; swordfish and bigeye tuna, which both feed in deep oceanic layers, showed similarities in their contaminant profiles. Geographically, the distinct DDT profiles of fish from the Mozambique Channel suggested an exposure to different DDT sources, in line with regional use of this insecticide and coupled with an extended residence time of fish in the Channel. To our knowledge, the data presented here are among the first obtained for legacy and emerging organic contaminants in various species of large pelagic predators from the WIO

PCDD/Fs Occurrence in a Mediterranean Coastal Lagoon (Etang de Thau, France): Concentrations and Patterns in Different Environmental Compartments

Thau lagoon is one of the largest Mediterranean lagoons. Located on the French Mediterranean coast along the Gulf of Lion (Figure 1), it covers a surface of 75 km2 with an average depth of 4.5 m and is isolated from the Mediterranean Sea by an offshore bar. The lagoon appears to be under an intense anthropogenic pressure. For instance, the results of the French Monitoring Network (RNO Réseau National d’Observation) shows high contamination of the Thau lagoon sediments by hydrophobic organic compounds such as, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) 1. However, only few data in relevant environmental compartments from Thau lagoon on other important groups of persistent organic pollutants (POPs), like polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), have been reported to date. Moreover, the dynamics, long term impacts and ultimate fate of the contamination induced by these chemicals in the lagoon is not well known. The aim of this work was to investigate the PCDD/Fs concentrations and patterns in air (where no data are available yet), sediments and mussels from Thau Lagoon. The influence of the atmosphere in the accumulation of these POPs in the aquatic system was studied. Two land air sampling sites were set up in the lagoon and sediments and mussels samples were collected from selected stations. Total PCDD/Fs air concentrations (particle + gas phase) measured ranged from 6.9 to 25.7 WHO-TEQ fg m-3. A concentration of 13.8 WHO-TEQ pg g-1 was found for PCDD/Fs in surface sediments and a value of 0.8 WHO-TEQ pg g-1 was found for the analyzed mussels in the lagoon.JRC.H.5-Rural, water and ecosystem resource

PCDD/F and PCB multi-media ambient concentrations, congener patterns and occurrence in a Mediterranean coastal lagoon (Etang de Thau, France)

International audienceAmbient concentrations, congener patterns and multi-media distribution of PCDD/Fs and PCBs were determined in air, water, sediment andmussels in a semi-enclosed marine ecosystem (Thau lagoon, France). sum2,3,7,8-PCDD/F and sum7ICES PCB air concentrations (0.2-1.4 and31-57 pg m-3, respectively) were typical of rural areas. Concentrations in the water column were very low for PCDD/Fs (163-476 fg L-1)and low for PCBs (138-708 pg L-1). PCDD/F and PCB concentrations found in surface sediment (0.15-1.6 and 2.5-33 ng g-1 d.w., respectively)and mussel (13-21 pg g-1 d.w. and 10-39 ng g-1 d.w., respectively) were medium levels. PCDD/F congener patterns observed in air,water particulate phase and sediments were similar suggesting direct coupling among these compartments and atmospheric inputs of PCDD/Fsinto the lagoon. Conversely, for the same set of samples, similar patterns were not observed for PCBs in the mentioned compartments