HEAVY METAL CONTAMINATION IN HERBAL DRUGS AND ITS TOXICOLOGICAL IMPLICATIONS: A REVIEW

Herbal drugs are widely used across the world for the management of various acute and chronic ailments due to their perceived safety and natural origin. However, increasing evidence suggests that contamination of herbal medicines with heavy metals poses a serious risk to human health. Heavy metals such as lead and arsenic may enter herbal formulations through contaminated soil, irrigation water, environmental pollution, improper processing, or lack of quality control during manufacturing. Chronic exposure to these metals through prolonged consumption of contaminated herbal products can result in significant toxic effects involving the nervous system, gastrointestinal tract, liver, kidneys, and hematopoietic system. Several clinical reports have linked the use of certain traditional and herbal preparations with symptoms of heavy metal poisoning, highlighting the growing public health concern associated with their unregulated use. This review aims to summarize the sources of heavy metal contamination in herbal drugs, with special emphasis on lead- and arsenic-induced toxicity, along with the toxic effects of other commonly reported heavy metals. The review also discusses the clinical manifestations associated with heavy metal exposure and emphasizes the need for stringent quality control, standardization, and regulatory monitoring to ensure the safety of herbal medicines. [1,2] KEYWORDS: Herbal drugs, Heavy metal poisoning, Lead poisoning, Arsenic poisoning