Sub-chronic and Trophic Effects of TBT and DBT in American plaice (Hippoglossoides platessoides)

Abstract

Tributyltin (TBT) has been used as antifouling in ship paints and directly released into marine environment for many decades. TBT and its metabolites dibutyltin (DBT) and monobutyltin (MBT) are known to cause multiple toxic stresses to aquatic organisms at cellular and ecosystem levels. In the current study, the marine fish American plaice (Hippoglossoides platessoides) was used to investigate TBT and DBT bioaccumulation and to evaluate its morphological effects after trophic and sub-chronic exposure doses. Four groups of seven male and female mature fish were separated in four tanks (control, TBT, TBT water quality control and DBT groups), and exposed by food to four and eight doses of TBT and DBT (30 ng g –1 each three days, corresponding respectively to 12 and 24 days of exposure). After four and eight doses, three animals were anesthetized from each tank and liver, spleen and posterior kidney were sampled for histopathological studies and muscle for chemical analysis. Chemical results showed that only TBT was bioaccumulated in muscle with a decreasing rate after 24 days. Necrotic areas were observed in liver and vacuolated cells and cellular deposit were found within renal tubules for both TBT and DBT exposed groups although DBT and MBT were not detected in fish muscle.