Assessment of Heavy Metal Contamination in Locally Cultivated Medicinal Plants

Abstract

The past few years have witnessed a notable rise in global trade in medicinal plants, prompting concerns about the safety and quality of imported herbal materials. This investigation aims to evaluate the presence of heavy metal contamination, specifically arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg), in imported medicinal plants commonly used in traditional and alternative medicine practices. Samples were obtained from a range of international sources via local markets and herbal shops. Atomic Absorption Spectroscopy was used for the quantitative analysis of heavy metals, following the appropriate digestion protocols. The results revealed that a significant portion of the examined samples exceeded the permissible limits set by the World Health Organization (WHO) and national pharmacopeias, with lead and cadmium identified as the most common contaminants. Possible sources of contamination encompass polluted soils, industrial emissions, and insufficient post-harvest handling. The results indicate the urgent need for robust quality control standards, effective traceability systems, and regular screening of imported botanicals. This investigation highlights the significant health risks associated with heavy metal exposure from herbal remedies. It emphasizes the need for regulatory alignment in the global herbal trade to ensure consumer safety and therapeutic reliability.