Assessment of heavy metal content of commonly consumed herbal medicines in Sindh, Pakistan

In Pakistan, herbal medicines are extensively consumed by a major portion of people for the treatment of numerous ailments. Nowadays, the contamination of heavy metals in herbal medicines is a serious concern due to its toxic effects on human health. In the present study, quantitative evaluation of four heavy metals, namely, iron (Fe), cadmium (Cd), nickel (Ni), and copper (Cu), was carried out in forty herbal medicines, frequently sold in the markets of Sukkur and Khairpur, Pakistan, without any quality assurance. Conventional wet acid digestion method was used for the dissolution of samples, and the concentration of heavy metals was determined by using flame atomic absorption spectrometry. Diverse concentration of metals was observed in different herbal medicines. The levels of Fe, Cd, Ni, and Cu were in the range of 30.3-798 mg/kg, 0.002-0.007 mg/kg, 1.52-27.3 mg/kg, and 15.2-194 mg/kg, respectively. The findings of our study were also compared with the WHO maximum permissible limits. It was observed that the concentrations of these heavy metals in most of the analyzed samples were within the permissible limits set by the WHO. Only a few samples of herbal medicines exceeded the recommended levels of Ni and Cu. These medicines should be regularly checked for quality assurance to avoid chronic exposure of metal to human beings.

Automated summary

Herbal medicines are widely used in Pakistan, but the contamination of heavy metals in these medicines poses a serious concern for human health. A study was conducted to evaluate the levels of iron, cadmium, nickel, and copper in forty commonly sold herbal medicines in Sukkur and Khairpur, Pakistan. Most of the analyzed samples were within the WHO permissible limits for heavy metals, but a few samples exceeded the recommended levels of nickel and copper, highlighting the importance of regular quality assurance checks for these medicines to prevent chronic exposure to metals.