Potentially Toxic Metals: Their Effects on the Soil-Human Health Continuum

As the foundation of nutritious foods lies in the soil, the consumption of crops grown in contaminated soils may pose an elevated risk of health issues through the soil-plant-human pathway. The impact of heavy metals (HMs) and metalloids on the physiological and biochemical responses of plants can have adverse effects on both growth and yield. The excessive accumulation of these substances in plant tissues poses a significant challenge to public health. HMs possess the capability not only to function as carcinogens but also to act as co-carcinogens, thereby activating specific chemical compounds. According to the World Health Organization (WHO) reports, the target values, representing the desirable maximum concentrations of HMs in the soil, follow the order: Cr > Pb > Zn > Cu > Ni > Cd. This implies that Cd poses the highest potential risk, given its target value of 0.8 mg/kg, while Cr carries the lowest potential risk, with a target value of 100 mg/kg. Various agricultural management practices are recognized as significant pathways that induce the accumulation of metals in the soil and the surrounding environment. Hence, understanding the origin and status of HMs in the environment, along with assessing their potential risks and developing strategies to mitigate these risks, becomes crucial. This study aims to evaluate different facets of the soil-human health continuum concerning potentially toxic metals.