Risk and health implications of polluted soils for crop production
Studies of polluted soils have shown heavy metals contamination of the soils as well the uptake of these toxic elements by plants. Consequently, there are reasons for concern over elevated concentration levels of heavy metal/toxic elements in polluted soils. This can ultimately result in high human and animal exposure to these toxic elements through food-chain transfer, ingestion of wind blown dust or direct ingestion of soils. The toxic effects caused by excess concentrations of heavy metals in living organisms include competition for sites with essential metabolites, replacement of essential ions, reactions with –SH groups, damage to cell membranes and reactions with the phosphate groups.