Comparative Study on Heavy Metals and Hydrocarbons Accumulation in Cassava Tubers Harvested from Four Different Locations in Rivers State, Nigeria

The threat to humans, animals, and plants life by pollution due to gas flare and oil and gas industrial activities cannot be overemphasized. This study compared the hydrocarbons and heavy metals accumulation in cassava tubers harvested from four different locations in Rivers State. The study areas include Rukpoku, Rivers State University (RSU) farm, Eleme community and Nkpolu-Oroworukwo community. Cassava tubers were collected from farms located in the aforementioned areas, prepared and analyzed for hydrocarbons and heavy metals contents. Standard spectro-analytical method was used to determine the concentrations of zinc (Zn), iron (Fe), lead (Pb), copper (Cu) and manganese (Mn), while polycyclic aromatic hydrocarbons (PAHs), total polycyclic hydrocarbon (TPH) and BTEX (benzene, toluene, ethyl benzene, xylene) were analyzed using standard chromatographic procedure. Results obtained from the analyses revealed the presence of heavy metals in all the samples in the order Eleme > Nkpolu-Oroworukwo > Rukpoku > RSU farm. Pb was not detected in the entire sample analyzed, Mn was below the permissible range, while Zn, Fe and Cu were above the permissible range. TPH was detected in all samples analyzed in the order Eleme > Nkpolu-Oroworukwo > Rukpoku > RSU farm. RSU farm had the least concentration of PAH, While BTEX was not detected in all samples analyzed. The results suggest the presence of heavy metals and hydrocarbons (anthracene, acenaphthene, phenanthrene, fluoranthene, pyrene, benz (a) anthracene, benz (b) fluoranthene, indeno (1,2,3-cd) pyrene, dibenz (a, h) anthracene) in cassava tubers harvested from the study locations, but with greatest accumulation in samples from Eleme community and least in those from RSU farm. Consumption of such crops could pose health challenges to the consumers over time.