Bacteria, Aflatoxins And Fluoride Levels In Locally Processed Herbal Medicines From Nairobi County, Kenya

Abstract

The increased use of herbal medicines has come with challenges of safety, quality and efficient utilization. This study assessed the safety of the herbal medicines with regards to microbial contamination, aflatoxins and fluoride. It also assessed the quality of the herbal medicines with regards to harvesting, processing and storage. A cross-sectional survey, targeting key stakeholders dealing in herbal medicines in Nairobi County was undertaken. A non probability sampling involving 50 traders was done and 3 samples were obtained from each one of them. From the Nairobi Central business district 30 herbalists were sampled while in Kawangware and Dagoretti markets 10 herbalists were sampled from each market. The microbial contamination by Coliforms was tested using the membrane filtration method, while the Aflatoxins contamination was determined by using ELISA and High Pressure Liquid Chromatography. Fluoride was measured by direct potentiometric method. A total of 90 solid samples and 60 liquid samples were analyzed. The solid samples were not contaminated with Escherichia Coli, but 26.7% of samples contained Klebsiella pneumonia. The liquid herbal preparations were contaminated with both Klebsiella pneumonia and Escherichia coli 13.3% and 6.67% respectively. Liquid samples were not contaminated with aflatoxins, while, 24.0% of the solid samples contained aflatoxins subtypes B1, B2, G1 and G2 at various concentrations. Although the levels of aflatoxins reported in this study are within the acceptable limits, and because aflatoxins especially aflatoxin B1, are potent carcinogens there is an interest in the effects of long-term exposure to low levels of these important mycotoxins to humans. Safety of herbal medicines is therefore an important Public Health issue. If action is not taken, the levels of contamination are likely to increase adverse effect to public. Generally, the solid and liquid samples had fluoride concentrations within the range of 0.532 mg/L to 1.718 mg/L which was within the recommended WHO limits being 1.5 mg/L. This is expected given that the herbal medicine practitioners surveyed were from the same geographical area of Nairobi County and were most likely to share the same water source in preparation of the extracts. The liquid samples assessed for fluoride contamination were not hazardous to the consumer as fluoride levels were within acceptable levels. This study has shown that during preparations of various herbal medicines there is a need to use clean safe water and observe proper storage conditions in order to eliminate contamination of medicines.