Butyltins Contamination in Surface Water in Three Gorges Reservoir Region, China

In order to know the occurrence of butyltins in water environment in Three Gorges Reservoir Region (TGRR), China, surface water samples from Chongqing to Yichang in TGRR were collected in March 2012. All water samples were extracted by solid phase micro-extraction (SPME) and measured by gas chromatograph (GC) with mass spectrum (MS). Results showed that both the mainstream and tributaries of Yangtze River in TGRR were polluted with butyltins, and the concentrations of butyltins did not exhibit any specific trend of variation in surface water along the Yangtze River. Most of butyltins were MBT which was found in 21 of 28 sampling stations, and concentrations varied from ND to 38.90 ng Sn/L. TBT was the next most commonly found in 9 of 28 stations with the highest level of 393.35 ng Sn/L. DBT had the lowest detection rate and was detected only in 1 of 28 stations with the level of 23.09 ng Sn/L in Tongguanyi. Butyltin degradation index (BDI) in the surface water in TGRR suggested that fresh TBT inputs or may also be attributed to very slow degradation in this region. Our study indicated that the main source of TBT contamination in TGRR may attribute to shipping activities and that particular attention should be paid to the issue of butyltins pollution in TGRR.