Hepatic butyltin concentrations in beluga whales (Delphinapterus leucas) from the St Lawrence Estuary and northern Quebec, Canada

Butyltin (tributyltin TBT; dibutyltin DBT and monobutyltin MET) speciation was measured in the liver of beluga whales from the St Lawrence Estuary and Hudson Strait (northern Quebec), Using GC-MS, liver samples were analysed from 21 beluga whales found dead, stranded along the shores of the St Lawre nce during the period 1995-1998, In all cases, including a neonate specimen , the liver was contaminated with butyltin compounds with concentrations in the range 0.0-1-2.1 mg Sn kg(-1) on a dry weight basis, Liver samples of f ive beluga whales from Hudson Strait obtained in the summer of 1998 were al so analysed, For these animals, hepatic butyltin concentrations were consis tently below the detection Limit (<0.5 ng Sn g(-1) for MBT and <0.2 ng Sn g (-1) for DBT and TBT). Compared with published data on the contamination by TBT of the marine mammals of the SC Lawrence in 1988, these contemporary r esults clearly indicate that the level of contamination of the beluga whale s in this coastal marine ecosystem has not decreased ten Sears after regula ting the use of TBT-based antifoulants on small craft. Copyright (C) 2000 J ohn Wiley & Sons, Ltd.