Tissue distribution of HCH and DDT congeners and human health risk associated with consumption of fish collected from Kabul River, Pakistan

Abstract

Distribution of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) congeners in tissues of four different fish species and their associated potential health risks to local consumers are presented in this paper. The average ∑(HCHs+DDTs) concentration in Glyptothorax punjabensis (214ngg−1 wet weight (ww)) (carnivores) was found higher than Tor putitora (155ngg−1 ww) (herbivores). The distribution of ∑(HCHs+DDTs) in all fish tissues was found in order of liver>muscle>stomach>gills. The profile of congeners (β-HCH/∑HCH from 0.29–0.47) indicated that all selected fish species were contaminated with HCH because of its recent usage in the study area. Furthermore, DDT profile ((DDE+DDD)/∑DDT from 0.61–0.78) showed that fish contamination with DDT originated from past usage and long-time degradation mechanism. The average estimated daily dietary intake of ∑HCHs (15.0ngkg−1 day−1) was higher than ∑DDTs (12.5ngkg−1 day−1) by the local consumers via fish consumption. On the basis of both 50th and 95th percentile exposure levels, the carcinogenic hazard ratios for DDT and its congeners were exceeded one (safe limit) for all fish species, indicating a great potential cancer risk for local consumers with life time consumption of contaminated fish collected from Kabul River.