Assessment of Some Heavy Metal Levels and its Related Health Hazards in Two Staple Foods Grown in Mining Communities of Ebonyi State

Background: This study assessed the levels of some heavy metals in two staple foods grown within mining sites at Ishiagu and Enyigba communities of Ebonyi State. The control site was Umuezeokoha community. The present study is significantly important in respect to hazardous effect of heavy metal accumulation in staple food as there was no or scarcity of data available in Nigeria on this aspect.

Materials and Methods: The two commonly cultivated food crops namely Manihot esculentus (cassava) and Telfairia occidentalis (fluted pumpkin) were grown within <20m, 100m before mining sites. The crops were collected from the three farms at the peak of the harvesting period, processed and were analyzed for heavy metals using AAS technique.

Results: The results revealed that heavy metals; Pb, Cu, Ni, Zn and Mn in Manihot esculentus tubers in all the farms within Ishiagu and Enyigba mining sites were comparable to each other and control site but Cr levels in control site was higher than others and that of WHO/FAO maximum permissible limit. Only As from A2 in Ishiagu had the highest value and exceeded WHO/FAO maximum permissible limit. Fe from B1, B2 in Enyigba and that of control had the highest values when compared to others but Fe in all samples investigated exceeded WHO/FAO maximum. Also, Pb, Cu, Ni, Zn, and Mn in Telfairia occidentalis leaves in all the farms within mining sites were comparable to control site except As levels from A2 in Ishiagu and from control site which was higher compare to others including WHO/FAO maximum permissible limit. Cr only from A2 in Ishiagu, B2 and B3 in Enyigba was highest even with WHO/FAO maximum permissible limit. Fe too from all the farms in Enyigba and control had highest values even with WHO/FAO maximum permissible limit.

Conclusion: The results showed that the investigated food crops from two mining communities and the control site were not safe for consumption.