Bioaccumulation of Pesticides in Aquatic System of Edku Lake, Egypt: An Approach for Risk Associated With Fish Consumption

Monitoring of some organochlorines (OCs) and organophosphorus (OP) pesticide residues in Edku Lake during 2015-2016 have been determined in water, sediment and Tilapia fish to find out the extent of pesticides contamination and bioaccumulation into the lake. Pesticide residues were determined using gas chromatography equipped with appropriate detectors. The mean residues of ∑BHC, ∑DDT, total OCs, and OPs in water samples were 68.43, 14.17, 118.3 and 138.46 ppb, respectively. The corresponding residues in sediments were 8343.26, 5307.59, 21402.83 and 267.66 ppb, respectively. In fish muscles, the mean residues of ∑BHC, ∑DDT, methoxychlor and total OCs were 2513.56, 1916.85, 46175.05, and 57592.40 ppb, respectively. The corresponding values in fish gills were 3565.44, 16014.96, 13182.44, 35645.15 and 3318.10 ppb, respectively. Sum of BHC and DDT were the mostly detected in muscle samples accounting for 1593.60 and 916.53 ppb, respectively. Regarding bioaccumulation of examined pesticides, bioconcentration factor (BCF) was estimated to be in range 7.96-40701.50 for water/muscle ratio of OCs. In case of BCF for water/gills, the values ranged from 16.72 to 237090.17. BCF values obtained from ratio sediment/muscle or sediment/gills not exceeded than 100. These concepts indicate that OCs induced bioaccumulation in fish tissues may attributed to predicted risks associated with this kind of consumption. All findings represent concept that, Edku Lake represents reservoir of all pollutants coming from north governorates e.g. El-Behira.