Health Risk Assessment of Heavy Metals In Ameri Lead-Zinc Mining Community Via Consumption of Cassava ( Manihot esculenta Cruz) In Ikwo L.G.A., Ebonyi State, Nigeria

摘要

Background and Objective: In countries with rich mine deposits like Nigeria, solid mineral mining have the potential of contributing to economic development via enhancing employment opportunities and supporting national income among others. In Ebonyi State, Southeast Nigeria, solid mineral mining is next to agricultural sector in her economies. While the contributions of mining activities to the economic development of Ebonyi State vis-à-vis Nigeria is well acknowledged, the environmental and health impacts of mining on surrounding communities have been a major concern to the general public and stakeholders. The use of lands within the vicinity of mining sites as arable farmlands for the cultivation of edible food crops is increasingly worrisome. This study investigated the uptake of heavy metals by cassava food crop cultivated in farmlands within the vicinity of Ameri Pb-Zn mining site in Ikwo, Ebonyi State, Nigeria to extrapolate the associated ecological and health risks. Materials and Methods: The soil and cassava samples were obtained from farmlands in the vicinity of Ameri Pb-Zn mine site in Ikwo and a nearby farm land at Ndufu-Alike where there was no solid mineral mining in the vicinity (control site). The samples were processed and analyzed using standard protocols. Data obtained were analyzed using one way analysis of variance (ANOVA) by SPSS version 15.0 (Inc. Chicago, USA) and significant differences were established at P Fe > Pb > Cd > Ni > Cu > Cr and in cassava as: Zn > Fe > Pb > Cu > Cd > Ni > Cr. The results also indicated significantly higher (P Cd > Pb > Fe > Ni > Cr > Cu, soil-plant transfer factors: Zn > Cu > Fe > Pb > Cd > Ni > Cr and estimated Health Risk Indices (HRIs) for adult: Pb > Cd > Fe > Zn > Cu > Cr > Ni. Although the results showed that the dietary intake of metals were within permissible limit of Food and Agricultural Organization/World Health Organization, the estimated HRIs were > 1 for Pb, Cd and Fe in adults for the cassava. Conclusions: The high values of pollution load indices for the different metals in the samples indicated anthropogenic inputs and the soil-plants transfer coefficients and the estimated HRIs > 1 for Pb, Cd and Fe in adults for the cassava indicated increased ecological and health risks implications. Hence, the need for enacting and enforcing policies on environmental regulatory standards is urgent for optimal public health.