Pollution de l’environnement et changement climatique

Abstrait

Risk Assessment and the Translocation of Heavy Metals to Some Edible Vegetables in an Oil Palm Mill Site in Okada Community, Edo State, Nigeria

Erifeta G.O, Uyi-ohonba E.K, Njoya H.K, Osagiede P.E

Environmental damage caused by agricultural waste owing to increased agricultural activities is a problem of global concern. Following estimated data, up to 40% of the oil palm waste (biomass) including the Oil Palm Shell (OPS), oil palm Empty Fruit Bunch (EFB), Pressed Fruit Fibre (PFF), Oil Palm Trunks (OPT), Oil Palm Leaves (OPL) and palm oil mill effluent generated from Oil Palm Mill Sites (OPMS) in Okada Community in Edo State, Nigeria, are incinerated as part of the waste management procedures to reduce the physical nuisance they create, or a large portion of the POME is allowed to run off into adjourning rivers and vegetation in the processing sites. This study investigates the source and levels of heavy metals concentration in soil samples and in two commonly consumed vegetables grown in the study area; Amarantus hybridus and Talinum triangulate. Concentrations of Heavy metals present in soil sample assessed were 0.01, 0.54, 0.05, 0.01, 2.1, 0.10, and 11.5 for Pd, Cu, Cd, Cr, Zn, Ni, Fe respectively. The vegetables were found to bio accumulate most of the heavy metals although at less than the WHO/FAO, FEPA and E.U. standard limits. Vegetable samples Fe levels exceeded the permissible limit of 0.3 mg/kg for vegetable samples. Low concentrations of heavy metals might be due to the short duration that these palm oil mill sites are situated in a location before they are relocated to other sites owing to poor waste management. This important source of livelihood and sustenance for the Okada people is presently posing as environmental nuisance, destroying agricultural land and having effect on soil and plants owing to poor waste management practice.