peer reviewed | Elasmobranchs can bioaccumulate considerable amounts of persistent organic pollutants (POPs) and utilize several reproductive strategies thereby influencing maternal transfer of contaminants. This study provides preliminary data on the POP transfer from pregnant females to offspring of three species (Atlantic stingrays, bonnethead, blacktip sharks) with different reproduction modes (aplacental, placental viviparity). Polychlorinated biphenyl (PCB) levels were generally higher than any other POPs. Stingrays and blacktip shark embryos contained the lowest POP concentrations while bonnetheads and the blacktip adult female had the highest concentrations. Results suggest that are more readily transferred from the mother to the embryo compared to what is transferred to ova in stingrays. Statistically significant differences in levels of selected POPs were found between embryos from the left and right uterus within the same litter as well as between female and male embryos within the same litter for bonnetheads, but not for the blacktip sharks.

Soils are major reservoirs for many persistent organic pollutants (POPs). In this study, “newly” regulated POPs i.e. sum endosulfans (a-endosulfan, b-endosulfan, endosulfan sulfate), pentachlorobenzene (PeCB), and short-chain chlorinated paraffins (SCCPs) were determined in background samples from woodland (WL) and grassland (GL) surface soil, collected along an existing latitudinal UK-Norway transect. Statistical analysis, complemented with plots showing the predicted equilibrium distribution and mobility potential, was then explored to discuss factors controlling their spatial distribution. SCCPs were detected with the highest average concentrations (35 ± 100 ng/g soil organic matter (SOM)), followed by sum endosulfans (3 ± 3 ng/g SOM) and PeCB (1 ± 1 ng/g SOM). PeCB and sum endosulfans share many similarities in their distribution in these background soils as well as with several legacy POPs. A steep decline in concentrations of SCCPs with increasing latitude indicates that their occurrence is dictated by proximity to source regions, while concentrations of Sendosulfans peaked in regions experiencing elevated precipitation rates. | acceptedVersion

Chronic exposure to pollutants may represent a threat for wildlife.We tested whether adult survival rate, breeding probability and breeding success the year of sampling and the following year were affected by blood levels of mercury or persistent organic pollutants in Svalbard black-legged kittiwake Rissa tridactyla, by using captureemarkerecapture models over a five-year period. Survival rate was negatively linked to HCB levels in females, to chlordane mixture and oxychlordane, tended to decrease with increasing PCBs or DDE levels, but was unrelated to mercury. Breeding probability decreased with increasing mercury levels during the sampling year and with increasing CHL or HCB levels during the following year, especially in males observed as breeders. Surprisingly, the probability of raising two chicks increased with increasing HCB levels. Although levels of these legacy pollutants are expected to decline, they represent a potential threat for adult survival rate and breeding probability, possibly affecting kittiwake population dynamics. © 2015 Elsevier Ltd. All rights reserved. Heavy metals Kittiwake Population Pesticides PCBs | acceptedVersion

The role of polychlorinated biphenyls (PCBs) on exposure-related endocrine effects has been poorly investigated in wild birds. This is the case for stress hormones including corticosterone (CORT). Some studies have suggested that environmental exposure to PCBs and altered CORT secretion might be associated. Here we investigated the relationships between blood PCB concentrations and circulating CORT levels in seven free-ranging polar seabird species occupying different trophic positions, and hence covering a wide range of PCB exposure. Blood P7PCB concentrations (range: 61e115,632 ng/g lw) were positively associated to baseline or stress-induced CORT levels in three species and negatively associated to stress-induced CORT levels in one species. Global analysis suggests that in males, baseline CORT levels generally increase with increasing blood P7PCB concentrations, whereas stress-induced CORT levels decrease when reaching high blood P7PCB concentrations. This study suggests that the nature of the PCB-CORT relationships may depend on the level of PCB exposure. Arctic Antarctic Birds PCBs Glucocorticoids Stress | acceptedVersion

acceptedVersion

International audience | This study evaluates the efficiency of two small constructed wetlands installed in the regulatory grass strips between a drained plot and a river. The observed nitrate removal efficiencies were independent of the season or type of constructed wetland and ranged from 5.4 to 10.9% of the inlet amounts. The pesticide mass budgets ranged from −618.5 to 100%, depending on the molecule. The negative efficiencies were attributed to runoff and remobilization. In contrast, the highest efficiencies were associated with pesticides with high Koc and low DT50 (half-life) values, suggesting sorption and degradation. However, the effectiveness of these wetlands is limited for pesticides with low Koc or high DT50 values; thus, the use of these molecules must be reduced. Increasing the number of these small, inexpensive and low-maintenance wetlands in the agricultural landscape would reduce the level of water pollution whilst preserving the extent of cultivated land, but their long-term effectiveness should be evaluated.

acceptedVersion