Assessment, Accumulation, Toxicity and Importance of Heavy Metals in Agricultural Soil and Living System - Review

Heavy or toxic metals are metals which are harmful beyond the permissible level to human health and are heavier in density than water by more than five times. Living organisms require varying amounts of heavy metals. Heavy metals like copper, manganese, cobalt, iron, zinc and molybdenum are required by living organisms in a small amount. Soil is a crucial component of rural and urban environments, and in both places land management is the key to soil quality. This paper review was aimed to touch the accumulation, assessment and importance of some heavy metals in agricultural soils and to understand the present situation and the impact of heavy metal contamination of soils in the world, in this review, compare and analyze the contamination of various cities/countries, and explore background, impact and remediation methods of heavy metal contamination of soils. Their accumulation in crops and pollution to soil can decrease crop yield, quality and cause detrimental effect to human health through food chain. Heavy metals can enter to human through inhalation, ingestion, body contact and skin absorption. In recent years, with the development of the global economy, both type and content of heavy metals in the soil caused by human activities have gradually increased, resulting in the deterioration of the environment.