Pyrrolizidine alkaloids in honey: occurrence and profile analysis in Japan

In this study, we investigated the amounts of 15 types of pyrrolizidine alkaloids (PAs) and 12 corresponding N-oxides (PANOs) in honey samples purchased from retail stores, supermarkets, and internet stores in Japan using LC-MS/MS with a new sample preparation method. Among the 129 honey samples analysed, 93.8 % contained detectable levels above the limit of quantification, with concentrations ranging from 0.012 to 69.8 μg kg^-1, and mean and median values of 3.92 and 0.49 μg kg^-1, respectively. Among the 27 targeted PAs/PANOs, 17 were detected, with intermedine and lycopsamine exhibiting high detection rates. No significant differences were observed in contamination levels between Japanese and imported honey. However, PA profiles varied between Japanese and imported products. The margin of exposure values for PAs/PANOs exceeded 10,000, indicating low public health concern. Japanese honey profiles were classified into three groups, with Group 1 (Boraginaceae and Eupatorium species) accounting for over 50 % of the samples.