Effects of sediment contamination on physiological and biochemical responses of the polychaete Diopatra neapolitana, an exploited natural resource.

The present study reports metal and arsenic contamination in sediments, as well as element accumulation and partitioning in the polychaete Diopatra neapolitana in the Ria de Aveiro lagoon (Portugal). The polychaetes biochemical performance and tissue regenerative capacity were also evaluated. The concentration of elements in sediments showed an increase of contamination among areas (areas A-G), but higher bioaccumulation was observed in organisms from a less contaminated area (area C, BAF>1). This study evidenced that individuals with higher elements bioaccumulation presented higher LPO and lower GSH/GSSG and also exhibited lower capacity for body regeneration. Polychaetes biotransformation capacity as well as antioxidant defense mechanisms were not sufficiently efficient to withstand the excess of ROS leading to increased LPO when organisms presented higher bioaccumulation levels. Additionally, an increase of methalotionines was also observed in individuals with higher bioaccumulation of metals and As, suggesting an induction of detoxification processes.