How life history influences the responses of the clam Scrobicularia plana to the combined impacts of carbamazepine and pH decrease

In the present study, the bivalve Scrobicularia plana, collected from two contrasting areas (pristine location and mercury contaminated area), was selected to assess the biochemical alterations imposed by pH decrease, carbamazepine (an antiepileptic) and the combined effect of both stressors. The effects on oxidative stress related biomarkers after 96 h exposure revealed that pH decrease and carbamazepine induced alterations on clams, with greater impacts on individuals from the contaminated area which presented higher mortality, higher lipid peroxidation and higher glutathione S-transferase activity. These results emphasize the risk of extrapolating results from one area to another, since the same species inhabiting different areas may be affected differently when exposed to the same stressors. Furthermore, the results obtained showed that, when combined, the impact of pH decrease and carbamazepine was lower than each stressor acting alone, which could be related to the defence mechanism of valves closure when bivalves are under higher stressful conditions. •Environmentally relevant concentrations of CBZ and pH 7.1 impacted the performance of Scrobicularia plana.•The combination of CBZ and pH 7.1 did not induce higher impacts compared with stressors acting alone.•Clams from a polluted area showed greater alterations than clams collected from an unpolluted area. pH decrease and carbamazepine induced biochemical alterations on clams (Scrobicularia plana), with greater impacts on individuals from the contaminated area.