Determination of the heavy metal contents of frequently used herbal products in Pakistan

Purpose: To determine the heavy metal content of selected local and international herbal medicines sold for the treatment of various diseases in Pakistan. Methods: The different dosage forms of herbal medicines assessed were crude forms of syrups, gel, capsule, powder and tonic. Wet digestion method was used to prepare the herbal samples using nitric acid, and then analyzed for arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg), using MHS-15 mercury/hydride system and flame atomic absorption spectrometry (FAAS). Results: The investigated results displayed the Arsenic level (0.00 ppm to 0.580 ppm); Cadmium (0.001 ppm to 0.006 ppm); Lead (0.00 ppm to 1.078 ppm) and Mercury (0.001 ppm to 0.012 ppm). All results were found below the permissible limit of acceptability intake of the World Health Organization (WHO) and American Herbal Products Association (AHPA). The pH of the samples were in the range of 1.52 to 6.99. Conclusion: The findings reveal that the investigated herbal products available in Pakistan are safe with reference to heavy metals, and considered non-toxic for human consumption.

Automated summary

The study found that the heavy metal content in herbal medicines sold in Pakistan is within safe limits and below the acceptable intake levels set by the World Health Organization and the American Herbal Products Association. The pH levels of the samples ranged from 1.52 to 6.99. This indicates that the herbal products in Pakistan are safe for human consumption in terms of heavy metal toxicity.