Assessment of Nutritional Quality and Heavy Metal Contamination in Some Vegetables from the Mezam Division, Northwestern Region of Cameroon: Health Risk Implications

Vegetables are vital for nutrition, yet their nutritional quality and heavy metal content related to agricultural practices remain underexplored in the Mezam Division (MD), Northwest Region of Cameroon. This study aimed to identify prevalent agricultural practices related to soil amendments and pest management, and assess the carcinogenic effects of four commonly consumed vegetables: carrot (Daucus carota ssp. sativa), cabbage (Brassica oleracea), leek (Allium ampeloprasum), and tomatoes (Solanum lycopersicum), which were grown in three localities within the MD. A semi-structured questionnaire was used to gather information on farmers' practices, whereas standard analytical methods were used to assess proximate composition, vitamin C content and heavy metal concentrations. Health risk assessments have investigated estimated daily intake (EDI), hazard index (HI), and target cancer risk (TCR) models. The results revealed no significant differences (P > 0.05) in proximate composition among vegetables from the different localities. The moisture content and carbohydrate content ranged from 84.032±25% to 94.750±0.23% and from 1.990±0.52% to 12.279±2.82%, respectively. The crude fibre content ranged from 1.133% to 2.685%, and the ash content ranged from 0.416±0.01% to 1.706±0.04%. The protein and vitamin C contents varied from 0.713±0.061% to 1.484±0.21% and from 5.090±0.12% to 44.900±0.06%, respectively. Chromium (0.557 to 1.318 mg/kg), cadmium (0.942 to 1.885 mg/kg), and lead (1.552 to 2.154 mg/kg) exceeded the FAO/WHO limits. HI indicated a noncarcinogenic risk greater than unity, and the TCR values surpassed the 1×10−4 threshold, suggesting that long-term consumption poses cancer risks. The results of this study underscore the need for improved agricultural practices and monitoring of heavy metal contamination in vegetables to safeguard public health in the Mezam Division.