Microbiological, Parasitological and Heavy Metals Assessment of selected Vegetables in Offa Metropolis

Vegetables are vital dietary components, supplying essential nutrients for human health. However, their safety can be compromised by various contaminants. This study assessed the microbiological, parasitological, and heavy metal contamination of ten commonly consumed vegetables— Telfairiaoccidentalis, Amaranthus spp., Celosia argentea, Corchorusolitorius, Vernonia amygdalina, Solanumlycopersicum, Cucumissativus, Brassica oleracea, Daucuscarota, and Phaseolus vulgaris— purchased from markets in Offa metropolis, Kwara State, Nigeria. Standard microbiological methods were employed for bacterial and fungal enumeration and isolation, while parasitological assessment utilized the sedimentation method. Heavy metal detection was performed using Atomic Absorption Spectrophotometry (Buck Scientific Model 230). Total bacterial counts ranged from 1.30×104 to 1.00×105cfu/g and fungal counts range from 4.20×106 to 1.24×107cfu/g. Key bacterial isolates included Pseudomonas aeruginosa, Salmonella entericaserovarTyphi (molecularly confirmed), Staphylococcus aureus (molecularly confirmed), and Escherichia coli (molecularly confirmed). Fungal isolates primarily comprised Aspergillus niger, A. flavus, and Candida tropicalis. Parasitological investigation revealed significant infestation by Ascarislumbricoides and Balantidium coli. Alarmingly, concentrations of lead (0.50±0.01 mg/kg) and manganese (2.47±0.06 mg/kg) in some vegetable samples exceeded permissible limits set by the World Health Organization (WHO). These findings highlight significant microbial, parasitic, and heavy metal contamination in selected vegetables from Offa metropolis, indicating their potential as sources of public health concern and necessitating enhanced food safety interventions.