河蚬对太湖梅梁湾沉积物中HCHs和DDTs的生物富集

Bioaccumulation of HCHs and DDTs in Asiatic clam(Corbicula fluminea) exposed to sediments from Meiliang Bay,Taihu Lake

以采自清洁水体的河蚬（Corbicula fluminea）为实验生物，利用生物富集实验测试了河蚬对太湖梅梁湾水源地沉积物中HCHs和DDTs的生物富集。研究结果表明，将河蚬暴露于有机氯农药污染程度相似的太湖梅梁湾沉积物中（HCHs和DDTs浓度分别为1.5～1.8 ng/g （以干重计）和1.1～1.7 ng/g （以干重计））后，随着暴露时间的延长（24～168 h），河蚬对有机氯农药的富集量随着暴露时间逐渐增加。试验结束时各样点中河蚬对HCHs和DDTs的富集量分别为（9.4±2.2）ng/g （以干重计）、（20.7±7.6）ng/g（以干重计）。实验水体沉积物中HCHs和DDTs的生物沉积物富集因子（BSAF）分别为1.5±0.1和4.4±0.7。生物-沉积物富集因子（BSAF）与有机物的辛醇-水比值（Kow）存在显著正相关。

Bioaccumulations of sediment-associated HCHs and DDTs in Meiliang Bay, Taihu Lake, were assessed using a benthic organism Asiatic clam （Corbicula fluminea） collected from a clean water. The results showed that the total concentrations of HCHs and DDTs pesticides in sediment samples were 1.5 to 1.8 ng/g dry weight and 1.1 to 1.7 ng/g dry weight, respectively. After 24 to 168 h exposure to different sediments, concentrations of HCHs and DDTs in Asiatic clam＇s muscle increased significantly with exposure time and were （9.4±2.2）ng/g dry weight and （20.7±7.6）ng/g dry weight, respectively at 168 h. The biota-sediment accumulation factors （BSAFs） were calculated. BSAFs of HCHs and DDTs were 1.5±0.1 and 4.4±0.7, respectively. Significant correlation was observed between biota-sediment accumulation factors and octanol and water partitioning coefficients （Kow） for both groups of chemicals.