Distribution characteristics and ecological risk assessment of butyltins in sediments at typical dumping sites in China

Abstract

The distribution characteristics of butyltins (BTs, sum of monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT)) in sediments at typical dumping sites in China were investigated and evaluated. The results revealed that the contents of MBT, DBT, TBT, and BTs were 4.96–22.28, 1.14–2.83, 2.58–4.98, and 9.49–27.25 ng Sn g−1 dw (dry weight), respectively. The TBT was mainly from historical input, and at most of the dumping sites, the BT contents were higher inside the dumping sites than outside the dumping sites. Assessment of the effectiveness of the International Convention on the Control of Harmful Anti-fouling Systems on Ships (AFS Convention) revealed that the content of BTs decreased at most dumping sites, and the AFS Convention was effective in China. The U.S. Environmental Protection Agency’s TBT screening value and the Oslo-Paris Convention’s TBT evaluation standard were used to assess the ecological risk. The ecological risk assessment results revealed that potential ecological risks still persisted.