Heavy metals and microbial contamination of palm oil produced and sold at some markets in Kogi East Area, Kogi State, Nigeria

The physicochemical, microbial and heavy metal contamination of palm oil samples randomly selected from three different markets (Ankpa, Anyigba and Idah Markets) in Kogi State, Nigeria, was investigated. The results revealed the presence of moisture (0.5, 0.4, 0.4%); impurity (0.4, 0.4, 0.3%) and free fatty acid (13, 12.8, 12.3%) for Ankpa, Anyigba and Idah Markets respectively. The microbial contaminants isolated were Enterobacter sp, Bacillus sp, Proteus sp, Micrococcus sp, Staphylococcus sp, Pseudomonas sp, Aspergillus sp, Candida sp, Mucor sp, Rhizopus sp and Penicillium sp. The presence (ppm) of heavy metals in the samples was analyzed using atomic absorption spectroscopy for chromium, cadmium, lead, arsenic, copper and iron. All the tested metals except chromium and lead were detected in samples from Anyigba Market with the mean concentration of arsenic (0.29), iron (4.66), cadmium (0.001) and copper (0.006). The metals detected in samples from Idah Market were cadmium (0.46), arsenic (0.19), iron (7.34), chromium (0.04) and copper (0.03). Only three metals, arsenic (0.04) cadmium (0.01) and iron (1.88) were detected in samples from Ankpa Market. From the findings, the microbial load of the samples fell within the acceptable limits stipulated by World Health Organization limits. However, most of the heavy metals assayed for were above acceptable limits. The present findings indicate the need for refining of locally produced palm oil to eliminate metal contaminants because of the health implication of their accumulation in the body.