PHENYLTIN RESIDUES IN HORSESHOE CRABS, TACHYPLEUS-TRIDENTATUS FROM JAPANESE COASTAL WATERS

Concentrations of phenyltins were determined in horseshoe crabs, Tachypleus tridentatus collected from Japanese coastal waters. Concentrations of Sigma PT in the crab hepatopancreas ranged from 77 to 12,410 ng/g (wet wt) which were, on average, 2-fold higher than those of butyltins. Presence of considerable levels of phenyltins in eggs suggested oviparous transfer effecting future generations. Transfer rates of phenyltins via eggs were proportional to corresponding burden in the hepatopancreas. The bioconcentration factors of TPT in the crab hepatopancreas were in the ranges of 8-44 X 10(4). Relatively lower concentrations of DPT than TPT suggested lower rates Of metabolism by Tachypleus. High concentrations of phenyltins and butyltins in horseshoe crabs may have serious implications for their survival, particularly at their early life stages.