Transplacental transfer of phenyltins from a pregnant Dall’s porpoise (Phocoenoides dalli) to her fetus Original Research Article

The maternal to fetal transfer of monophenyltin (MPT), diphenyltin (DPT), and triphenyltin (TPT) was investigated for the first time in a cetacean species, a mother–fetus pair of Dall’s porpoises (Phocoenoides dalli) collected off the Sanriku coast, Japan. The mother individual was contaminated by phenyltin compounds, and the muscle, blubber, and liver accounted for 90% of the total phenyltin burden. A two-generation phenyltin contamination via transplacental transfer was demonstrated. This study revealed that the transfer rate was 0.29% for total phenyltins to a fetus of about 6-month-old. Unlike in the mother, the fetal liver could not be considered the target organ for all the phenyltins studied. In a ca. 100 kg-weight mother Dall’s porpoise and its fetus of 2.21 kg-weight, approximately 153 μg (TPT, 139 μg; DPT, 9.4 μg; MPT, 4.2 μg) and 0.44 μg of total phenyltins (TPT, 0.38 μg; DPT, 0.03 μg; MPT, 0.03 μg) were found, respectively. The body burden of TPT consisted of 91% and 86% of the total phenyltin burdens in the maternal and fetal bodies, respectively.