Determination of Fungi and Multi-Class Mycotoxins inCamelia sinensisand Herbal Teas and Dietary Exposure Assessment

In this paper, a study of fungal and multi-mycotoxin contamination in 140Camellia sinensisand 26 herbal teas marketed in Latvia is discussed. The analysis was performed using two-dimensional liquid chromatography with time-of-flight mass spectrometry (2D-LC-TOF-MS) and MALDI-TOF-MS. In total, 87% of the tea samples tested positive for 32 fungal species belonging to 17 genera, with the total enumeration of moulds ranging between 1.00 x 10(1)and 9.00 x 10(4)CFU g(-1). Moreover, 42% of the teas (n= 70) were contaminated by 1 to 16 mycotoxins, and 37% of these samples were positive for aflatoxins at concentrations ranging between 0.22 and 41.7 mu g kg(-1). Deoxynivalenol (DON) and its derivatives co-occurred in 63% of the tea samples, with their summary concentrations reaching 81.1 to 17,360 mu g kg(-1). Ochratoxin A (OTA), enniatins, and twoAlternariatoxins were found in 10-37% of the teas at low concentrations. The dietary exposure assessment based on the assumption of a probable full transfer of determined mycotoxins into infusions indicated that the analysed teas are safe for consumers: the probable maximum daily exposure levels to OTA and the combined DON mycotoxins were only 0.88 to 2.05% and 2.50 to 78.9% of the tolerable daily intake levels.