Background: There is increased reliance on traditional herbal medicines by several millions of people worldwide, especially in West Africa and
Nigeria in particular. This is due to escalating cost of good quality drugs and consequent proliferation of faked cheaper drugs. However, non
standardization of production and handling methods have resulted in herbal medicines with varying quality and safety indices, thus resulting in
possible public health concerns. This work investigated the microbial load and aflatoxin levels in herbal medicines from selected states in Nigeria.
Materials and Methods: A total of 210 samples obtained from various renowned herbal medicine practitioners from some selected states in Nigeria,
based on their medicinal uses, were analyzed to determine the microbial load by the plate count method and aflatoxin contamination levels using thin
layer chromatography with aflatoxin standards.
Results: At least six bacterial genera (
Bacillus
,
Pseudomonas
,
Salmonella
,
EPEC,
EHEC,
Staphylococcus
and other coliforms) and 6 fungal genera
(
Aspergillus
,
Penicillium
,
Rhizopus
,
Cladosporium
,
Geotricum
and
Candida
) were isolated. Aflatoxin B1, B2 and G1 were detected in varying
concentrations in the samples analyzed, with an average occurrence of 18.6%. Some of these herbal concoctions were found to contain unacceptably
high bioload, according to WHO standards.
Conclusion: Microbial contamination and the presence of aflatoxins in herbal medicines appear to be an endemic problem in Nigeria, as observed in
this work, probably due to poor observation of basic hygiene during preparations and poor storage conditions. The findings in this work may serve in
developing and instituting public health standards for the production and safety of herbal remedies in Nigeria.
