Factors determining bioaccumulation of neurotoxicant Hg in the zebra mussels (Dreissena polymorpha): Influence of biometric parameters, sex and storage of shell.

One of benthic organisms exposed to contact with mercury in the southern Baltic is alien species of clam: Dreissena polymorpha. As this organism is increasingly dynamic in various regions of the world including the southern Baltic region, it is reasonable to ask whether it tolerates elevated concentrations of xenobiotics? Does it effectively eliminate Hg? The study determined the effects of biometric parameters and water temperature on the rate of accumulation and efficiency of eliminating Hg from body. Investigations focused on the shell which represents poorly-recognized role in the process of Hg distribution in clams. The results showed that especially during warm season, clams effectively reduced the levels of Hg in their body by the biodilution of Hg and reproduction. Important factor influencing detoxification was Hg transfer from the soft tissue to the shell. This protects the soft tissue against the toxic effect of Hg.