Profiles of heavy metals (cadmium and lead) in five herbal supplements used in Iloilo City

Abstract

Background: Studies have shown an increased consumption of herbal supplements in the country due to the inability to afford conventional medications and the avoidance of their perceived side-effects. However, due to current lack of information in the processing, monitoring, and distribution, issues about the safety of herbal supplements, particularly their heavy metal content which when taken repeatedly and at certain amounts can induce adverse systemic effects that can further lead to disease. Objective: This study aimed to determine and compare the levels of heavy metals (cadmium and lead) in five selected herbal supplements commercially available in Iloilo City, using Flame Atomic Absorption Spectrometry) FAAS. Methods: This was an experimental in vitro research study conducted at the University of the Philippines Visayas Analytical Services Laboratory. Pre-treatment of the top five popular herbal supplements in Iloilo City (MX3 capsule, Koi Herbal capsule, Xanthone plus, Ampalaya plus, and Dr. Alfred's Mangosteen) included wet ashing and filtration. The resulting filtrates were diluted and subjected to Flame AAS to determine the concentrations of two heavy metals in the samples. The absorption values of at least five standard solutions of each metal were obtained to generate the corresponding calibration curve which was used to calculate the heavy metal were content of the prepared samples. The levels of the heavy metals in each sample were quantified and compared to the permissible limits of heavy metal content. Results: Among the herbal supplements tested, Dr. Alfred's Mangosteen (0.33 mg/kg) had the highest cadmium level and the only herbal supplement exceeding the permissible limit (>0.3 mg/kg) set by the World health Organization and Food and Drug Administration for cadmium. On the other hand, Ampalaya Plus (3.95 mg/kg), Dr Alfred's Mangosteen (3.09 mg/kg), Xanthone plus (1.32 mg/kg), and Koi herbal capsule (0.99 mg/kg) have lead levels consecutively above the permissible limit (>0.5 mg/kg) set by United States Pharmacopeia and International Conference on Harmonization. Conclusion: Dr. Alfred's Mangosteen herbal supplement was found to have cadmium levels above the permissible limits while four of the five herbal supplements marketed in Iloilo City have lead exceeding the permissible limits implying that continued and prolonged use of those supplements may result to adverse health effects to consumers.