Abstract

Heavy metal contamination of agricultural soils poses a significant threat to food safety and public health worldwide. This comprehensive review examines the mechanisms of heavy metal uptake in vegetables grown on contaminated soils and evaluates the associated health risks. The study analyzed uptake patterns of cadmium (Cd), lead (Pb), mercury (Hg), arsenic (As), and chromium (Cr) in common vegetables including leafy greens, root vegetables, and fruiting crops. Soil contamination sources include industrial activities, mining operations, sewage sludge application, and atmospheric deposition. Results indicate that leafy vegetables demonstrate the highest bioaccumulation factors for most heavy metals, with cadmium showing the strongest correlation between soil concentration and plant uptake (r = 0.89, p < 0.001). Root vegetables, particularly carrots and radishes, exhibited significant lead accumulation, while arsenic concentration was notably elevated in rice and other cereal crops. The bioavailability of heavy metals was influenced by soil pH, organic matter content, and redox conditions. Health risk assessment revealed that chronic consumption of contaminated vegetables could exceed tolerable daily intake limits for children and adults in heavily polluted areas. Mitigation strategies including phytoremediation, soil amendments, and proper agricultural practices are essential to reduce heavy metal transfer from soil to food crops. This review emphasizes the urgent need for comprehensive monitoring programs, stringent soil quality standards, and public health interventions to protect vulnerable populations from heavy metal exposure through the food chain.