IMIS

We sampled variegated scallops (Mimachlamys varia) at sites characterized by different contaminants and contamination levels to study the short-term responses of this species to physiological stress. We used biomarkers (SOD, MDA, GST, laccase, citrate synthase and phosphatases) as indicators of oxidative stress, immune system alteration, mitochondrial respiration and general metabolism. In parallel, concentration of 14 trace metals and 45 organic contaminants (PAHs, PCBs, pesticides) in tissues were measured. Scallops were collected outside and during their reproductive season to investigate temporal variability in contaminant and biomarker levels. As a source of concern, a location that was identified as a reference site on the basis of inorganic contaminant levels presented the same level of some persistent organic pollutants (DDT and its metabolites) than more impacted sites. Assessing the effects of chemical contamination on natural populations collected in situ requires the integration of i) multiple indicators of individual and population health and stress response, ii) different types of contaminants that may be present in the environment. Our active biomonitoring approach applied to natural populations of variegated scallops underlines how different locations on the infralittoral zone can display significantly distinct contamination profiles despite being geographically close. The dataset is splitted in two parts: one for biomarkers and trace elements tested on same individuals, one for organic contaminants tested on other individuals in parallel. It was not possible to test the same individuals at the sametime, because we would have been short of flesh else.