Assessment of Heavy Metal Concentrations in Food Samples of Oil and Non-Oil Producing Communities in Rivers State, Nigeria

Aim: To compare heavy metal concentrations in locally consumed vegetables and food crops grown in oil and non-oil-producing communities in Rivers State.

Study Design: Descriptive cross-sectional study.

Place and Duration of Study: Kegbara Dere and Omerelu communities in Gokana and Ikwerre local government areas, Rivers State, Nigeria between November 2021 and January 2022.

Methodology: Heavy metal concentrations (lead (Pb), cadmium (Cd) mercury (Hg), and arsenic (Ars) of vegetables, food crops, and sea animals selected from the local markets and rivers of the two communities were determined. Data entry and analysis were done using IBM Statistical Package for Social Sciences (SPSS)version 21. T-test was used to compare the mean differences in heavy metal concentrations of vegetables and food crops between the two communities.

Results: Mean concentrations of Lead (0.70 vs 0.01) Cadmium (0.09 vs 0.00) and Arsenic (0.18 vs0.00) respectively of vegetables grown in the oil-producing community were higher than that of the non-oil-producing community. The difference was not statistically significant (P>0.05). Mean concentrations of Lead (1.48 vs 0.00) Cadmium (0.28 vs 0.00), and Arsenic (0.41 vs 0.00) of the food crops in the oil-producing community were higher than that of the non-oil-producing community. However, only the difference in the lead concentrations was significant (P<0.05) The concentrations of Pb, Cd, and Ars in sea creatures collected from the surface waters of the oil-producing community were above WHO-recommended limits.

Conclusion: Food grown in oil-polluted environments has higher heavy metal concentrations compared to non-polluted environments and therefore highlights the need for continued and increased efforts towards complete remediation of the polluted regions of the Niger Delta.