Quality Control and Standardisation of Herbal Medicines Produced by Selected Companies in Lagos State

The herbal medicine industry in Nigeria is characterised by a large number of producers operating at varying scales of sophistication, with quality control practices ranging from rigorous to negligible. This study evaluated quality control and standardisation practices of herbal medicinal products manufactured by five registered herbal medicine companies in Lagos State against standards specified by the World Health Organisation quality control methods for medicinal plant materials and NAFDAC regulatory guidelines. Products selected for analysis included capsules, tinctures, syrups, and dried powders marketed for specific therapeutic purposes. Chemical assays performed included determination of heavy metals, pesticide residue screening, moisture content, total ash, acid-insoluble ash, swelling index, microbial limit testing, and marker compound quantification by high-performance liquid chromatography. Lead and cadmium were detected above WHO limits in products from two manufacturers. Microbial contamination, including mould counts above acceptable limits, was recorded in three herbal powder formulations. Only one of five manufacturers conducted routine high-performance liquid chromatography-based potency testing of marker compounds. Documentation of in-process quality controls was absent in three facilities. These findings reveal significant quality gaps in the Lagos herbal medicine industry, particularly regarding heavy metal contamination and microbial quality. The study urges NAFDAC to strengthen post-market surveillance, require third-party quality certification for herbal medicine exports, and support analytical capacity building in the sector.

Keywords: herbal medicine quality control, heavy metals, NAFDAC, Lagos State, standardisation