Integrated assessment of the health status of mussels Mytilus galloprovincialis in the Bay of Biscay

LANDRO, S.M.; ARRIGHETTI, F.; BILBAO, E.; CAJARAVILLE, M.P.

Congreso; 5. 32nd Congress New European Society for Comparative Physiology and Biochemistry; 2022

Integrated monitoring approaches combining the measurement of pollutants and biomarker responses at different levels of biological organisation have been widely used to study the health status of marine ecosystems. The main objectives of this work are 1) to assess levels of trace metals, total PAHs, and total PCBs in mussels and sediment and 2) to study cell and tissue biomarkers in Mytilus galloprovincialis collected in June 2021 in Plentzia (reference site) and the leisure harbour of Arriluze (polluted site). In sediment, total PAH values were higher than the limit of detection (LOD) in both sites whereas total PCB was higher than the LOD only in Arriluze. Contrary to previous results, in mussels, total PAH and PCB content were under the LOD in both sites. In agreement, there were no significant differences between sites in the peroxisomal acyl CoA oxidase activity. The content of all metals in sediments was much higher in Arriluze than in Plentzia. Regarding metal bioaccumulation in mussels, Cd, and Pb were higher in Arriluze while Ar was lower. The Comet assay revealed that levels of DNA strand breaks were significantly higher in Arriluze than in Plentzia while there were no differences between sites for micronuclei frequency although the frequency of nuclear buds was higher in Arriluze. The digestive gland was more damaged than the gonad and the histopathological condition index in Arriluze was significantly higher if was estimated without parasites. Finally, the condition idex was higher in Arriluze, possibly because all the individuals from Plentzia presented a high degree of parasitosis. The sex ratio in Arriluze was 1F:3M, which might indicate an endocrine disruption effect that will be further studied. Overall, these results are relevant to understanding the long-term trends of legacy pollutants and the health status of sentinel mussels in the area.