渤海疏浚物中丁基锡提取方法优化及其分布特征

Optimization of extraction and distribution characteristics of butyltins in dredged materials from the Bohai Sea.

为了解渤海海域疏浚物中丁基锡(BTs,一丁基锡(MBT)、二丁基锡(DBT)、三丁基锡(TBT)之和)污染状况,选取渤海周边四个疏浚工程,采用单一变量法对沉积物中提取BTs的条件优化后分析疏浚物中BTs的含量.结果表明,活化铜粉添加量4.50g、二氯甲烷/二氯乙烷(V:V=1:1)混合萃取剂和0.5%的环庚三烯酚酮溶液是疏浚物中BTs提取最佳条件.渤海疏浚物TBT、DBT、MBT均被检出,其含量范围分别为2.93~7.96、1.07~2.27和4.99~9.00ng Sn/g(干重,下同).大部分工程疏浚物中BTs含量空间分布总体呈距岸越近TBT含量越高的趋势,BTs含量与其他国家和地区的研究相比处于较低水平,且TBT均为历史输入.生态风险评价表明,渤海疏浚物中TBT的生态风险处于较低水平.但根据国际公约对疏浚物海洋倾倒的管理建议,有必要对研究区域疏浚物海洋倾倒活动进行持续关注或管控.

In order to understand the pollution of butyltins(BTs,sum of monobutyltin(MBT),dibutyltin(DBT)and tributyltin(TBT))in the dredged materials from the Bohai Sea,four dredging projects around the Bohai Sea were selected.The extraction conditions of BTs in sediment were optimized by single variable method,and then the BTs in the dredged materials were analyzed.The results showed that the optimal conditions for extracting BTs in dredged materials were the addition of 4.50g of activated copper powder,dichloromethane/dichloroethane(V:V=1:1)mixed extractant and 0.5%tropolone solution.TBT,DBT and MBT were detected in the dredged materials from the Bohai Sea.Their contents ranged from 2.93 to 7.96,1.07 to 2.27 and 4.99 to 9.00ng·Sn/g(calculated by dry weight,the same below)respectively.In most dredging projects,the spatial distribution of TBT generally showed a trend of higher content closer to the coast,BTs content was at a low level compared to research in other countries and regions,and TBT were historical input.The ecological risk assessment results showed that the ecological risks of TBT in dredged materials from the Bohai Sea were at a low level.However,according to the management recommendations for the ocean dumping of dredged materials by international conventions,it was necessary to continue pay attention to or control the ocean dumping of dredged materials in the study area.