RESUMO
Concentration and human health risks of heavy metals (Pb, Cu, Cr, Cd, As, Ni) in water, sediment, crab (Tympanotonus fuscatus) and periwinkle (Callinectes amnicola) were assayed in New Calabar River, Nigeria. Results revealed that concentration (mg/L) of the metals in water in the two seasons studied, ranged from 1.1E-2 ± 1.0E-3 for Cd to 2.90 ± 0.03 for Cu. In sediment, the concentration (mg/kg) ranged from 1.1E-2 ± 1.0E-3 for As to 5.17 ± 0.04 for Ni. In biota, the concentration (mg/kg) ranged from 0.01 for As in crab to 19.22 for Cu also in crab. Estimated human health risk from the metals contamination due to consumption of biota gave each of HQ and HI as < 1, indicating no risk except at Agip's sample location where HI was > 1. Estimated human health risk due to dermal absorption through swimming, indicated no risk as each of HQ and HI was < 1. These make the river unpolluted except at Agip's sample location.
