Contamination by butyltin compounds in sediments from Thailand

Butyltin compounds (BTs) including tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) were analysed in sediments collected from coastal areas of Thailand in 1995. Contamination by BTs have been widespread along the coastal areas with concentrations of MBT, DBT and TBT in surface sediments ranging from 7 to 410, 2 to 1900 and 4 to 4500 ng g−1 (dry weight basis), respectively. High TBT concentrations were associated with large commercial or far seas vessels areas, while the levels at high fishing boat and coastal mariculture areas were lower. Large commercial ship and fishing boat hulls might be significant sources of BT contamination in Thailand coastal waters. Degradation of TBT in sediments might be higher in tropics than in sub-tropical zone. To our knowledge, this is a first report on the detection of BTs in sediments from Thailand.