Non-point source pollution is a cause of major concern within the European Union. This is reflected in increasing public and political focus on a more sustainable use of pesticides, as well as a reduction in diffuse pollution. Climate change will likely to lead to an even more intensive use of pesticides in the future, affecting agriculture in many ways. At the same time, the Water Framework Directive (WFD) and associated EU policies called for a “good” ecological and chemical status to be achieved for water bodies by the end of 2015, currently delayed to 2021–2027 due to a lack of efficiency in policies and timescale of resilience for hydrosystems, especially groundwater systems. Water managers need appropriate and user-friendly tools to design agro-environmental policies. These tools should help them to evaluate the potential impacts of mitigation measures on water resources, more clearly define protected areas, and more efficiently distribute financial incentives to farmers who agree to implement alternative practices. At present, a number of reports point out that water managers do not use appropriate information from monitoring or models to make decisions and set environmental action plans. In this paper, we propose an integrated and collaborative approach to analyzing changes in land use, farming systems, and practices and to assess their effects on agricultural pressure and pesticide transfers to waters. The integrated modeling of agricultural scenario (IMAS) framework draws on a range of data and expert knowledge available within areas where a pesticide action plan can be defined to restore the water quality, French “Grenelle law” catchment areas, French Water Development and Management Plan areas, etc. A so-called “reference scenario” represents the actual soil occupation and pesticide-spraying practices used in both conventional and organic farming. A number of alternative scenarios are then defined in cooperation with stakeholders, including socio-economi

Partitioning tissue metal concentration into subcellular compartments relecting 'toxicologically available'pools may provide good descriptors of the toxicological efects of metals on organisms. Here we investigatedthe relationships between internal compartmentalization of Cd, Pb and Zn and biomarker responses in a model soil organism: the earthworm. The aim of this study was to identify metal fractions reflecting the toxic pressure in an endogeic, naturally occurring earthworm species (Aporrectodea caliginosa) exposed torealistic field-contaminated soils.After a 21 days exposure experiment to 31 field contaminated soils, Cd, Pb and Zn concentrationsin earthworms and in three subcellular fractions (cytosol, debris and granules) were quantified. Differentbiomarkers were measured: the expression of a metallothionein gene (mt), the activity of catalase (CAT) andof glutathione-s-transferase (GST), and the protein, lipid and glycogen reserves. Biomarkers were furthercombined in an integrated biomarker index (IBR).The subcellular fractionation provided better predictors of biomarkers than the total internal contentshence supporting its use when assessing toxicological bioavailability of metals to earthworms. The mostsoluble internal pools of metals were not always the best predictors of biomarker responses. metallothioneinexpression responded to increasing concentrations of Cd in the insoluble fraction (debris + granules). Proteinand glycogen contents were also mainly related to Cd and Pb in the insoluble fraction. On the other hand,GST activity was better explained by Pb in the cytosolic fraction. CAT activity and lipid contents variationswere not related to metal subcellular distribution. The IBR was best explained by both soluble and insolublefractions of Cd and Pb.This study further extends the scope of mt expression as a robust and specific biomarker in an ecologicallyrepresentative earthworm species exposed to field-contaminated soils. The genetic lineage of the individuals,assessed by DNA barcoding with cytochrome c oxidase subunit I, did not inuence mt expression.

International audience | To support environmental management programs, there is an urgent need to know about the presence and understand the dynamics of major contaminants in seabird communities of key marine ecosystems. In this study, we investigated the concentrations and trophodynamics of trace elements in six seabird species and persistent organic pollutants (POPs) in three seabird species breeding on Grand Connétable Island (French Guiana), an area where the increase in human population and mining activities has raised concerns in recent years. Red blood cell Hg concentrations in adults were the highest in Magnificent frigatebirds Fregata magnificens (median: 5.6 μg g−1 dw; range: 3.8-7.8 μg g−1 dw) and lowest in Sooty terns Onychoprion fuscatus (median: 0.9 μg g−1 dw; range: 0.6-1.1 μg g−1 dw). Among POPs, dichlorodiphenyldichloroethylene (p,p’-DDE) was the most abundant compound in plasma of Cayenne terns Thalasseus sandvicensis (median: 1100 pg g−1 ww; range: 160±5100 pg g−1 ww), while polychlorinated biphenyls (PCBs) were the most abundant compound class in plasma of Magnificent frigatebirds (median: 640 pg g−1 ww; range 330±2700 pg g−1 ww). While low intensity of POP exposure does not appear to pose a health threat to this seabird community, Hg concentration in several adults Laughing gulls Leucophaeus atricilla and Royal terns Thalasseus maximus, and in all Magnificent frigatebirds was similar or higher than that of high contaminated seabird populations. Furthermore, nestling red blood cells also contained Hg concentrations of concern, and further studies should investigate its potential health impact in this seabird community. Differences in adult trophic ecology of the six species explained interspecific variation in exposure to trace element and POPs, while nestling trophic ecology provides indications about the diverse feeding strategies adopted by the six species, with the consequent variation in exposure to contaminants.

Partitioning tissue metal concentration into subcellular compartments relecting 'toxicologically available'pools may provide good descriptors of the toxicological efects of metals on organisms. Here we investigatedthe relationships between internal compartmentalization of Cd, Pb and Zn and biomarker responses in a model soil organism: the earthworm. The aim of this study was to identify metal fractions reflecting the toxic pressure in an endogeic, naturally occurring earthworm species (Aporrectodea caliginosa) exposed torealistic field-contaminated soils.After a 21 days exposure experiment to 31 field contaminated soils, Cd, Pb and Zn concentrationsin earthworms and in three subcellular fractions (cytosol, debris and granules) were quantified. Differentbiomarkers were measured: the expression of a metallothionein gene (mt), the activity of catalase (CAT) andof glutathione-s-transferase (GST), and the protein, lipid and glycogen reserves. Biomarkers were furthercombined in an integrated biomarker index (IBR).The subcellular fractionation provided better predictors of biomarkers than the total internal contentshence supporting its use when assessing toxicological bioavailability of metals to earthworms. The mostsoluble internal pools of metals were not always the best predictors of biomarker responses. metallothioneinexpression responded to increasing concentrations of Cd in the insoluble fraction (debris + granules). Proteinand glycogen contents were also mainly related to Cd and Pb in the insoluble fraction. On the other hand,GST activity was better explained by Pb in the cytosolic fraction. CAT activity and lipid contents variationswere not related to metal subcellular distribution. The IBR was best explained by both soluble and insolublefractions of Cd and Pb.This study further extends the scope of mt expression as a robust and specific biomarker in an ecologicallyrepresentative earthworm species exposed to field-contaminated soils. The genetic lineage of the individuals,assessed by DNA barcoding with cytochrome c oxidase subunit I, did not inuence mt expression.

[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | Hazard assessment of chemical contaminants often relies on short term or partial life-cycle ecotoxicological tests, while the impact of low dose throughout the entire life cycle of species across multiple generations has been neglected. This study aimed at identifying the individual and population-level consequences of chronic water contamination by environmental concentrations of three organic micropollutants, ibuprofen, bisphenol A and benzo[a]pyrene, on Aedes aegypti mosquito populations in experimental conditions. Life-history assays spanning the full life-cycle of exposed individuals and their progeny associated with population dynamics modelling evidenced life-history traits alterations in unexposed progenies of individuals chronically exposed to 1 mg/L ibuprofen or 0.6 mg/L benzo[a]pyrene. The progeny of individuals exposed to ibuprofen showed an accelerated development while the progeny of individuals exposed to benzo[a]pyrene showed a developmental acceleration associated with an increase in mortality rate during development. These life-history changes due to pollutants exposure resulted in relatively shallow increase of Ae. aegypti asymptotic population growth rate. Multigenerational exposure for six generations revealed an evolution of population response to ibuprofen and benzo[a]pyrene across generations, leading to a loss of previously identified transgenerational effects and to the emergence of a tolerance to the bioinsecticide Bacillus turingiensis israelensis (Bti). This study shed light on the short and long term impact of environmentally relevant doses of ibuprofen and benzo[a]pyrene on Ae. aegypti lifehistory traits and insecticide tolerance, raising unprecedented perspectives about the influence of surface water pollution on vector-control strategies. Overall, our approach highlights the importance of considering the entire life cycle of organisms, and the necessity to assess the transgenerational effects of pollutants in ecotoxicological studies for ecological risk assessment. Finally, this multi-generational study gives new insight about the influence of surface water pollution on microevolutionary processes.

Under laboratory conditions, the effects of thiamethoxam were investigated in larvae, pupae and emerging honey bees after exposure at larval stages with different concentrations in the food (0.00001 ng/µL, 0.001 ng/µL and 1.44 ng/µL). Thiamethoxam reduced the survival of larvae and pupae and consequently decreased the percentage of emerging honey bees. Thiamethoxam induced important physiological disturbances. It increased acetylcholinesterase (AChE) activity at all developmental stages and increased glutathione-S-transferase (GST) and carboxylesterase para (CaEp) activities at the pupal stages. For midgut alkaline phosphatase (ALP), no activity was detected in pupae stages, and no effect was observed in larvae and emerging bees. We assume that the effects of thiamethoxam on the survival, emergence and physiology of honey bees may affect the development of the colony. These results showed that attention should be paid to the exposure to pesticides during the developmental stages ofthe honey bee. This study represents the first investigation of the effects of thiamethoxam on the development of A. mellifera following larval exposure.

International audience

The exposure to legacy polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDDs) and unrestricted 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE), bis (2-ethylhexyl)-2,3,4,5-tetrabromophthalate (BEH-TEBP) and 2-ethylhexyl-2,3,4,5-tetrabromo-benzoate (EH-TBB) was examined in tail feathers of 76 birds belonging to ten predatory species inhabiting Pakistan. In addition, different feather types of six individuals of Black kite (Milvus migrans) were compared for their brominated flame retardant (BFR) levels. Black kite was found to be the most contaminated species with a median (minimum-maximum) tail feather concentration of 2.4 (0.70-7.5) ng g(-1) dw for Sigma PBDEs, 1.5 (0.5-8.1) ng g(-1) dw for Sigma HBCDDs and 0.10 (<LOQ-0.1) ng g(-1) dw for BTBPE. Among unrestricted BFRs, BTBPE was detected only in Black kite and Little owl (Athene noctua), whereas BEH-TEBP and EH-TBB were not detected in any species. BDE-47 was found to be the most prevalent BFR compound in aquatic species, while BDE-99 and -153 were more abundant in terrestrial species. For HBCDDs, alpha-isomer was generally recorded as the most prevalent BFR in both terrestrial and aquatic species. The concentrations of BFRs differed significantly (all P < 0.01) among species, trophic guilds and between habitats, the latter for PBDEs only (P < 0.04), whereas differences among taxonomic affiliations and groups with different feeding regimes were not significant (P > 0.05 for both). Similarly, no significant concentration differences were observed among different feather types (all P > 0.05) suggesting their similar exposure. While variables such as species, trophic guild and delta N-15 values were evaluated as major predictors for BFR accumulation in the studied species, we predict that combined effects of just mentioned factors may govern the intra- and interspecific differences in BFR contamination profiles. We urge for further investigation of BFR exposure and potential toxicological effects in predatory birds from Asia with a more extensive sample size per species and location.

International audience | Abstract Spreading livestock manure as fertilizer on farmlands is a widespread practice. It represents the major source of heavy metal(loid)s (HM) input in agricultural soils. Since zinc (Zn) is present at high concentrations in manure, it poses special environmental concerns related to phytotoxicity, groundwater contamination, and introduction in the food chain. Therefore, investigations on the fate and behavior of manure-borne Zn, when it enters the soil environment, are necessary to predict the environmental effects. Nevertheless, long-term field studies assessing Zn speciation in the organic waste matrix, as well as within the soil after manure application, are lacking. This study was designed to fill this gap. Using SEM-EDS and \XAS\ analysis, we reported the following new results: (i) ZnS made up 100% of the Zn speciation in the pig slurry (the highest proportion of ZnS ever observed in organic waste); and (ii) ZnS aggregates were about 1-μm diameter (the smallest particle size ever reported in pig slurry). Moreover, the pig slurry containing ZnS was spread on the soil over an 11-year period, totaling 22 applications, and the resulting Zn speciation within the amended soil was analyzed. Surprisingly, ZnS, i.e. the only species responsible for a nearly 2-fold increase in the Zn concentration within the amended soil, was not detected in this soil. Based on SEM-EDS and \XAS\ observations, we put forward the hypothesis that Zn in the pig slurry consisted of nano-sized ZnS crystallites that further aggregated. The low stability of ZnS nanoparticles within oxic and complex environments such as the studied soil was the key explanation for the radical change in pig slurry-borne Zn speciation after long-term amendments.