Sources, effects and present perspectives of heavy metals contamination: soil, plants and human food chain

Abstract

The poisoning of agricultural soils with heavy metals (HMs) is a severe threat to the worldwide food supply, human health, and plant life. The health and production of crops are negatively impacted when HM levels in agricultural soils reach hazardous levels. The major heavy metals are chromium (Cr), arsenic (As), nickel (Ni), cadmium (Cd), lead (Pb), mercury (Hg), zinc (Zn) and copper (Cu). These metals may be found everywhere in the environment, including in things like soil, food, water, and even air. These materials cause changes in the properties of soil and also harm plants, which reduces crop production. Crop type, growth conditions, elemental toxicity, developmental stage, soil chemical and physical properties, and the presence and bioavailability of HMs in the soil solution are all factors that affect how toxic HMs are to crops. By interfering with their normal function and structure in cellular components, HMs can hinder a variety of metabolic and developmental processes. Humans are susceptible to a wide range of serious diseases when they consume these affected plant products. The kidneys, brain, intestines, lungs, liver, and other organs in the human body are all negatively impacted by exposure to these metals. This review assesses (1) contamination of heavy metal in soils through different sources, like Anthropogenic and natural; (2) the effect on microorganisms and the chemical and physical properties of soil; (3) the effect on plants as well as crop production; and (4) entering the food chain and associated hazards to human health. Finally, we found some research gaps and indicated future work. The discharge of heavy metals into the environment must be strictly regulated if people are to feel secure in their surroundings.