Review on How Herbal Medicines/Preparations are being Contaminated Using Local Methods
DOI:
https://doi.org/10.31632/ijsblc.2025.v02i01.001Keywords:
Contaminants, Herbal Remedies, Microorganisms, Microbial Contaminants, Public Health, Policy Frame Work, Quality Control, Safety, ToxicityAbstract
This review documents currently known pathogenic microorganisms that are associated with herbal remedies as well as their health impacts on consumers and discusses the need for consistent regulatory practices as a form of quality assurance of herbal remedies. Phytomedical practices are used since ancient time but remain crude despite a growing number of users around the world. Importantly, there is a potential public health emergency as some herbal remedies contain microbial contaminants and heavy metals as a legacy of crude production techniques. Therefore, there is a need to put mechanisms in place to ensure that herbal remedies are safe for human use. Herbal remedies typically contain phytochemicals that exhibit antimicrobial activities, but issues linked to the toxicity of the crude extracts, method of extraction and purification, the dosage of administration, and microbial contaminants have negative implications on the practice, the general public, and users. Some microorganisms associated with herbal medicines have been known to cause serious harm, especially to children, the elderly, and immune-compromised people. Some microbes that have been isolated from herbal remedies include Escherichia, Salmonella, Pseudomonas, Streptococcus, Staphylococcus, Klebsiella, Bacillus, Enterococcus, Proteus, Citrobacter, Moraxella, Serratia, Citrobacter, Enterobacter, Shigella Candida, Aspergillus, Cladosporium, Rhizopus, Mucor, and Alterneria. Also, some harmful materials like heavy metals, dust, pesticidal residues, microbial contamination, and toxins have been isolated from adulterated herbal remedies. There is an urgent need to adopt more strategic quality control practices to reduce the density and diversity of microbes and other contaminants found in formulated and ready-to-use herbal medicines. Some important strategies would be knowledge sharing, formulating policies, and pharmacovigilance, which are capable of ensuring the quality, safety, and effectiveness of traditional and complementary medicine in the national health systems.
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