Moulds and mycotoxins in herb tea and medicinal plants

The level of toxigenic moulds and mycotoxins were analyzed in 62 samples of medicinal plant material and 11 herbal tea samples. The most predominant fungi detected were: Aspergillus, Penicillium, Mucor, Rhizopus, Absidia, Alternaria, Cladosporium and Trichoderma. Aspergillus flavus, a known producer of the aflatoxin mycotoxin, was present in 11 or 18% of the 62 medicinal plant samples and in 1 or 9% of the herbal tea samples. The medicinal plant samples, contaminated with A. flavus were also analyzed for the mycotoxins aflatoxin, ochratoxin and zearalenone; ochratoxin was found in one of the 7 samples analyzed. This study suggests that medicinal plant material and possibly herbal teas, if stored improperly allowing for mould growth, should be analyzed for mould and mycotoxin prior to use.