Chemical and ecotoxicological characterization of the “

Oil spills are an important source of PAHs in marine and coastal areas and comprise a short- and long-term threat for aquatic organisms. Some PAHs are known to be toxic, in particular mutagenic and/or carcinogenic, and their toxicological effects must be evaluated. Here, the impact of the “Erika” oil spill, which occurred at the end of 1999, was studied by combining chemical (PAH analyses) and toxicological approaches (biological effect assessment). “Erika” elutriates have been found to be more toxic than the elutriate obtained with a crude oil, Bal 250, inducing deleterious effects in Mytilus galloprovincialis and Crassostrea gigas embryos and in Isochrysis galbana algae. The embryotoxicity test in mussel is more sensitive than growth test in I. galbana. Naphthalenic compounds make up more than 95% of total PAHs quantified in elutriates. “Erika” elutriates are enriched with naphthalene, methyl-naphthalene, anthracene and higher-molecular-weight compounds. On the contrary, Bal 250 elutriate is characterized by the highest dibenzothiophene, methyl-dibenzothiophene and dimethyl-dibenzothiophene levels. Weathering does not highly affect the toxicity of the “Erika” oil. This study also confirms the potential impact of the “Erika” fuel on the biological quality of sea water and sediments from Traict du Croisic on the Atlantic coast of France

Long term effects of an early exposure and continuous exposure to pyrolitic PAHs on zebrafish behavioral responses.

International audienc

Long term effects of an early exposure and continuous exposure to pyrolitic PAHs on zebrafish behavioral responses.

International audienc

Contamination of marine sediments by microplastics and adsorbed organochlorine pollution (chlordecone) in coral reefs of Guadeloupe (Lesser Antilles)

International audienc

Long term effects of an early exposure to PAHs on zebrafish behavioural responses

International audienc

Reproduction and offspring defects after exposure to PAHs mixtures.

International audienc

Reproduction and offspring defects after exposure to PAHs mixtures.

International audienc

Ability of polymeric membranes to take into account pollution peaks: Exposure to continuous and discontinuous PAH pollution in pilot river.

Over the last years, polymeric membranes have been used as passive samplers to assess hydrophobic organic contaminant concentrations in aquatic environments. The amount of contaminant accumulated in situ during long exposure periods enables the determination of a so called time-weighted average dissolved concentration in water, which is supposed to assimilate the contamination variations over time (Huckins et al., 1993). The objectives of this study were (i) to show if polymeric membranes are reliable to quantify micropollutants in the receiving environment by comparing the actual exposure concentration to the mean concentration estimated by the sampler; (ii) to understand how polymeric membranes assimilate a concentration that varies over time. After being spiked with PRCs, two types of polymeric membranes (LDPE and PDMS) were deployed during 21 days in channels bypassing the French river Gave in Lacq. The flow rate was controlled in the channels and three scenarios of pollution were tested. The first scenario reproduced chronic pollution by continuous injection of PAHs (anthracene, chrysene and benzo[a]pyrene). Two levels were tested: Environmental Quality Standard (EQS) level and 1/3 of the EQS level. The second scenario reproduced an accidental pollution by an injection of PAHs in the river during the first 3 days of the 21-day exposure. The third scenario was a discontinuous pollution with injection of PAHs during 3 periods of 3 days separated by 4 days. For the two latest scenarios, the same quantity of PAHs was released than during the first scenario. A duplicate of each sampler were retrieved at various time intervals to follow the PAH accumulation and the PRC elimination. During the experiment, grab samples of water were regularly analysed. PRC elimination and PAH accumulation were simultaneously observed for all the compounds allowing the determination of the time-weighted average dissolved concentrations in water for each duration of exposure. For the first scenario with continuous injections of PAHs, the concentrations calculated from passive samplers were the same for all exposure durations and consistent with the quantity of PAHs released in the channel. These results validated the laboratory calibration of kinetic parameters (presented in another IPSW abstract: Lorgeoux et al. 2013) and the use of PRC to correct in situ environmental exposure conditions. For the second and third scenarios with discontinuous injections, the accumulated quantities of PAHs followed the means of exposure concentrations. For the heaviest PAHs (chrysene and benzo[a]pyrene) the calculated concentrations were consistent with the average concentrations of grab samples. This demonstrates that polymeric membranes really incorporate changes in concentration over time for these molecules. For anthracene, the results also were conclusive for the scenario with 3 injections of 3 days. But for a single injection during the first 3 days of the 21-day period, most anthracene were desorbed leading to a measured concentration underestimated compared to the theoretical value. For PAHs of low molecular weight, the exchange kinetics seems too fast to assimilate a pollution peak in the time-weighted concentration