氯苯类化合物在珠江水系的西江(广东段)水体和水草中的分布现状

Distribution of Chlorobenzenes in Water and Waterseeds of Xijiang Branch (Gangdong section) of the Pearl River

在2005年5月和12月在珠江水系西江(广东段)上/中/下游4个位点采集水样和水草样,用GC/ECD法对水样和水草样中氯苯类化合物(CBs)的含量进行了测定分析。结果表明:在水样和水草样中几乎所有的CBs的同系物均被检出。5月份水样和水草中CBs的检出总含量范围在115.90～397.06μg·L-1和1352.78～4019.07μg.g-1;12月份水样和水草中氯苯类化合物的检出总含量范围在181.87～696.74μg·L-1和1355.22～3927.20μg.g-1;水样中1,4-二氯苯和1,2,4-三氯苯的含量最高;水草中1,4-二氯苯和1,2-二氯苯,四氯苯的含量较高。水样含量与其他学者10年前的数据相比,有增高的趋势;水草对CBs有很高的富集系数,平均富集系数为0.64到3.57。这表明CBs将对食物链的其他生物具有潜在威胁。

The samples of river water and waterweeds were collected from four stations in Xijiang branch （ Gangdong section） of the Pearl River in May and December, 2005. The concentrations of chlorobenzenes （CBs） were determined by GC/ECD. The results showed that nearly every homologue of CBs was detected in the samples. The total concentrations of CBs in river water and waterweeds ranged from 115.90 to 397.06 ng·g^-1 and from 1352.78 to 4019.07 μg·g^-1 dry weight in May, respectively. The total concentrations ranged from 181.87 to 696. 74 ng·L^-1 in water and from 1355.22 to 3927.20 μg·g^-1 in waterweeds in December, respectively. The dominating homologues of CBs were 1,4 - dichlorobenzene and 1,2,4 - triehlorobenzene in river water, and 1,4 - dichloro-benzene, 1,2 -dichlorobenzene, tetrachlorobenzene in waterweeds. Compared with the data of literature, the concentration of CBs in river water were higher than that 10 years ago. The waterweeds possessed high concentration factors （CF） for CBs, and the average CF for CBs ranged from 0.64 to 3.57. So the CBs in waterweeds did potential damage to other organisms of food chains in Xijiang branch of the Pearl River.