Health Risk Effect of Heavy Metals from Pesticides in Vegetables and Soils: A Review

Abstract

Vegetables are vital to the human diet, and in particular provide the well-known nutrients to maintain normal physiological functions. The prolonged application of large amount of pesticides has resulted in heavy metal accumulation in vegetable farms. Exposure to heavy metals by the consumption of contaminated vegetables and its toxicity is a serious concern. This article reviews the effect of pesticides, heavy metals, heavy metals in vegetables, heavy metals in soil and transfer of heavy metals from soil to plants. However, a limited number of studies were found in the data base that examined the reduction of nutrients in vegetables due to heavy metal contamination. The heavy metals were found in leafy and fruit vegetables in different regions of the world and levels were above permissible limits in most of the vegetables. Specific study to human toxicity due to the contamination of heavy metals may be conducted. Furthermore, strategy and policy should be devised to control the heavy metals in vegetables, and those vegetables that are hyper-accumulators of heavy metals should be identified for awareness purposes.

Keywords: Vegetables, Heavy metals, Permissible limit, Toxicity, Contamination and Hyper-accumulators