Distribution Characteristics and Potential Risk of CBs in Aquatic Organisms from Typical Epidemic Areas of Schistosomiasis Prevalence

Eleven mollusca samples and 32 fish samples were collected from typical epidemic areas of schistosomiasis prevalence. The contents of 12 CB congeners in aquatic organism samples were measured using the GC/MS technique. The results indicated that 1,3-DIC, 1,4-DIC, 1,2-DIC and HCB were the most predominant CB congeners in the samples from the studying area. The geometric average of CBs in muscle of mollusca was 11 947 ng x g(-1) lipid weight. The summarized concentration of CBs in fish muscle ranged from 1 851 to 8 159 ng x g(-1) lipid weight. The highest concentration of CBs sum was detected in the catfish, while the lowest one was found in the crucian carp. The concentrations of CBs in fish samples were much higher than those reported in other countries, while in mollusca samples were at the same level. The estimated cumulative cancerigenic risks for the local residents consumed the aquatic organisms from the studying area were 1.49 x 10(-7) and 3.73-21.1 x 10(-7), respectively for mollusca and fish, both of which were acceptable.