Investigation of the Amount of Pesticide DDT Accumulated in Edible Fish of Shadegan Wetland and Evaluation of its Potential Risk to Consumers

Shadegan wetland, one of the largest wetlands inIran, is subject to different pollutants. One of these contaminants is the residue of organochlorine pesticides such as DDT and its metabolites used to combat pests. Residues of DDT and its metabolites (p,p/-DDT, o,p/-DDT, p,p/-DDE, o,p/- DDE, p,p/-DDD) were investigated in five edible fish species of Shadegan wetland, and the effect of the amount of this pesticide on the weight, age and diet was investigated. Total DDT (the sum of 5 metabolites) in Barbus grypus and Cyprino carpio was 6.50 and 3.27 ng g-1, respectively. Results showed that p,p/-DDE had a maximum concentration in all species and p,p/-DDT in Barbus sharpeyi (0.12 ng g-1) and Cyprino carpio (0.09 ng g-1), o,p/-DDE metabolite in Barbus grypus (0.12 ng g-1) and Aspius vorax (0.20 ng g- 1) and o,p/-DDT metabolite in Barbus barbules had a minimum concentration. These results show any new application of this pesticide in the land around the wetland. The mean concentration of DDTs was higher in weight group>320 g (6.77 ng g-1) and in age group>3 years (6.70 ng g-1) and those of an omnivorous diet (7.34 ng g-1) than in the other groups. The calculation of estimated daily intake (EDI) of this pesticide and comparison with international standards, showed no risks for residents in this area.