厦门海域水体中有机锡的存在形态与含量分布

Occurrence and distribution of organotin in seawater of Xiamen Bay

利用固相萃取-气相色谱-火焰光度检测(SPE-GC-FPD)对厦门海域表、底层海水中的有机锡化合物进行了分析检测。其中表层海水中检出的有机锡化合物以二丁基锡(DBT)为主,底层海水中以三丁基锡(TBT)为主,且TBT的浓度显著高于表层水。表层海水中总有机锡浓度在129.1—4 826.8 ng(Sn).L-1之间,底层海水则分布在321.6—1 954.5ng(Sn).L-1之间。结果显示,厦门港内及同安湾附近海域水体中的有机锡浓度远高于九龙江口及厦门西南海域,这与厦门海域船舶活动和网箱养殖密切相关。通过对鼓浪屿站点表层海水中有机锡化合物15 h的连续监测,推测光照对水体中有机锡的降解影响显著。

Organotin compounds in the surface and bottom water samples from the Xiamen Bay were collected and analyzed using SPE-GC-FPD （Soliol Phase Extraction Gas Chromatography Flame Photometric Detection）. Dibutlyltin （DBT） and Tributyltin （TBT） were the dominant organotin compounds in the surface and bottom water respectively, and the concentration of TBT in the bottom water were significantly higher than that in the surface water. The concentrations of organotin compounds ranged between 129.1 and 4826.8ng （Sn） ·L^-1in the surface water and between 321.6 and 1954.5ng （Sn） ·L^-1 in the bottom water. The highest organotin compound level was found near the Xiamen Harbor and the cage culture area of the Tong＇an Bay, and the lowest level in the Jiulong estuary and in the southwest waters of Xiamen Bay, suggesting that the organotin contamination in the Xiamen Bay is closely correlated with shipping activity and marine aguicultare. It is deduced that photolysis due to sunlight may be the major way for organotin compounds to degrade in sea water.