MOLECULAR DETECTION OF BACTERIA AND EFFECTS OF HEAVY METALS POLLUTION OF SELECTED AGRICULTURAL PRODUCT IN SOUTHERN NIGERIA

Abstract

Aim: The prevalence and systemic impact of heavy metals in agricultural products in the Ijaw region of southern Bayelsa State, Nigeria was evaluated on selected foods. The study aimed to evaluate and quantify the impact of heavy metals on selected foods, including the effect of boiling on heavy metal content, and to determine the resident microbial community in selected foods. Methods: Standard methods of analysis were employed to evaluate the toxicological effect of the heavy metals in the selected foods in vivo. The microorganisms in the foods were isolated and identified to molecular level using sequencing. Results: The results showed that boiling did not reduce the heavy metal content, and the results showed that the lead content in the food samples was high, exceeding the standards of the World Health Organization. A total of eight different isolates were differentiated by their Gram reactions and colonial morphology. Six of them were Gram negative and two were Gram positive. Their probable identities are Achromobacter, Escherichia, Acinetobacter, Proteus, Pseudomonas, Bacillus, Serratia and Staphylococcus. The highest bacterial load was found in the snail (1.8×104cfu/g). Microbial analysis revealed multiple bacterial species. In vivo experimental study showed that heavy metals have significant toxic effects on the kidneys and liver, affecting the sedimentation rate of white blood cells and red blood cells, indicating that heavy metal pollution in the region poses a serious health risk. Conclusion: The presence of lead and zinc in the selected agricultural products, especially cray fish, plantain, water yam and sweet potatoes is far higher than the WHO limit and this calls for attention.