Evaluation of Heavy Metals in Gills, Bones and Muscles of Fishes from Crude Oil Polluted Water of Ogoniland, Rivers State, Nigeria

Abstract

This study was carried out to determine the concentrations of heavy metals (cadmium, chromium, zinc, manganese, lead and iron) in organs (gills, bone and muscle) of Iutjanus campechanus and Chrysichthys nigrodidatatus from Gokhana, and Khana local government areas in River State, Nigeria were investigated. This heavy metals were determined using atomic absorption spectrophotometer (AAS). The result show that Iron was significantly more abundant in the gills, bone and muscle tissue than other element with mean concentration of 144-144.58 mg/kg in the gills, 18.19-39.77 mg/kg in the bone and 5.47-21.50 mg/kg in the muscle of both catfish and red snapper in Kaa while in bodo-city the concentration varies from 189-238 mg/kg in the gills, 42.16-45.39 mg/kg in the bone and 11.74-43.84 mg/kg in the muscle of both fishes respectively. Maximum concentration of Zinc was recorded in gills from Bodo-city for both fishes and minimum value was recorded in the muscle of both fish species in Kaa. High level of chromium, manganese and lead were recorded in bone of both species while the least concentration of all elements was recorded in the muscle of catfish and red snapper. It was observed that the level of metals in all organs were high except for chromium in the muscle which was lower than the permissible limits for human consumption designated by the USEPA, WHO, FAO. The result revealed that the distribution of the heavy metals follow the order Fe>Zn>Mn>Pb>Cd>Cr for Chrysichthys nigrodidatatus and Fe>Zn>Pb>Mn>Cd>Cr for Iutjanus campechanus while the distribution in the organs follow the other Gills>bone>muscle for both fish spices in Kaa and Bodo-City respectively. This reveal the health effect the people in the study area could be exposed to by the consumption of the muscle of catfish and red snapper which have high levels of these metals. Measures need to be taken as the level of Heavy metals detected in organs from the two site posed serious threat to the populace that feed on them.