Determination of organochlorine pesticides (OCPs) residues in some Egyptian freshwater fish

Fish plays an important role as a food source for the Egyptian population. Contamination of soil and water resources with many contaminants is a global problem to aquatic organisms. Thus, the study aimed to assess the levels of organochlorine pesticide (OCPs) residues in tilapia and catfish collected from four sites: the River Nile (fisherman), Fish aquaculture in Al-Sirou, affiliated to the National Institute of Oceanography and Fisheries, Kafr El-Sheikh aquaculture and local market of Giza governorate. The obtained results indicated that residue levels of OCPs were negligible, but fenpropathrin exhibited high levels (0.32757 and 0.03421 mg/kg) in tilapia fish of the River Nile and Giza market respectively. However, P, P-DDT and P, P-DDD exhibited the greatest levels (1.60097 and 0.11468 mg/kg) in catfish from Giza market respectively during winter. Heptachlor epoxide showed a mean value of 0.00965 mg/kg in catfish of Al-Sirou aquaculture, but endrin exhibited a mean value (0.00709 mg/kg) in catfish from the River Nile during summer. In water samples, heptachlor epoxide was significantly found at levels of 0.02659 and 0.06459 mg/L in samples from Al-Sirou and the River Nile during summer respectively. On the other hand, some treatments had been taken (different concentrations of acetic acid) to remove residues of pesticides in fish flesh. The treatments were very effective and 100% removal of residues from fish flesh was reached .From the results it could be noticed that OCPs are able to accumulate in fish tissue. More studies are needed to minimize their risk factors on human and environment.