Introduction: the use of the traditional herbal medicinal products (THMPs) has been increasing worldwide due to the readily availability of raw materials and low cost compared to the synthetic industrial preparations. With this trend in mind, the safety and quality of THMPs need to be addressed so as to protect the community. The present study evaluated the magnitude and risk factors associated with microbial contamination of liquid THMPs marketed in Mwanza.

Methods: a cross-sectional study was conducted in Mwanza city involving 59 participants from whom 109 liquid THMPs were collected and processed following the standard operating procedures. The data were analyzed using STATA software version 11.

Results: the median age (interquartile range) of participants was 35 (27-43) years, with males accounting for 36 (61%). Of 109 liquid THMPs collected, 89 (81.7%) were found to be contaminated; with predominant fecal coliforms being Klebsiella spp and Enterobacter spp. fortunately, no pathogenic bacteria like Salmonella spp and Shigella spp were isolated. There was a significant association of liquid THMPs contamination with low education level (p< 0.001), lack of formal training on THMPs (p=0.023), lack of registration with the Ministry of Health (p=0.001), lack of packaging of products (p<0.001) and use of unboiled solvents during preparation of THMPs (p<0.001).

Conclusion: there is high contamination rate of liquid THMPs in Mwanza City which is attributable to individuals and system-centered factors. Urgent measures to provide education to individuals involved in THMPs as well as setting up policies and regulations to reinforce THMPs safety is needed.