Human Health Risks Associated with Trace Element Contamination of Crassostrea gasar (Dautzenberg, 1891) from Lake Zowla-Aného Lagoon Hydrosystem (Southern Togo)

Trace element pollution in aquatic ecosystems is one of the most important threats of human health and food chain. In order to assess the concentration of trace element in soft tissues of Crasostrea gasar and the human health risk associated with its consumption, seven trace elements (As, Hg, Pb, Cd, Zn, Cu and Cr) were analyzed by Atomic Absorption Spectrometer coupled to a hydride and cold vapour generator. C. gasar were collected at Zowla and Zalive in the Lake Zowla-Aneho Lagoon hydrosystem. The results showed a significant inter-site variation of trace elements concentrations. The highest concentrations (mg kg−1 dry weight) were obtained at Zalive (0.69, 40.61, 246.47, 13.34, 10.13, 908.57 and 0.31) and lower concentration at Zowla (0.48, 34.26, 165.1, 10.4, 6.43, 766.3 and 0.2) respectively for As, Cd, Cu, Cr, Pb, Zn and Hg. The estimated daily intake (EDI) of each trace element in children is greater than the EDI for adults. The target hazard quotient (THQ) for children is higher than that for adults. For children, only Hg had a THQ 1). Also, the cancer risk (CR) for As and Cr were higher than 10-4 indicating that the onset of carcinogenic effects related to As and Cr in children and adults is probable. This study, therefore, suggests that the current environmental levels of trace metals are potential threats to the health of regular consumers of C. gasar of this hydrosystem.