Assessment of the Exposure to Pyrrolizidine Alkaloids from Tea Consumption in Lebanon

Abstract

Pyrrolizidine Alkaloids (PAs) are naturally occurring phytotoxins that can contaminate Camellia sinensis, posing health risks when present in tea. This study aimed to quantify six major PAs in loose black and green teas sold in the Beirut suburbs, compare obtained PA levels with current European regulatory guidelines and literature, and conduct an exposure assessment to evaluate health risks from PAs through tea consumption. PA levels were determined by sample extraction followed by UPLC-MS/MS analysis. A total of 28 tea samples, including black teas (n=14) and green teas (n=14), were analyzed, with sum PA concentrations averaging 120.1 µg/kg, and ranging between 25.8 – 607.7 µg/kg. Black tea averaged higher contamination levels (148.7 µg/kg) compared to green tea (91.2 µg/kg) (P˃0.05). Comparison by tea origin showed that Vietnamese-origin green tea had the highest average contamination, with 171.9 µg/kg. Exposure assessments revealed that 21.4% of samples from each tea type exceeded the EU adult limit, while more than half of the samples from each tea type surpassed the EU limit for children. In a short-term risk assessment, rarely did the samples pose a concern for adults, while a much larger proportion posed a concern for children. A long-term risk assessment indicated minimal risk for adults but moderate concern for children under average consumption, with higher risks associated with more frequent consumption habits for both age groups. These findings highlight potential dietary PA exposure exceeding safety limits, particularly for children and frequent tea consumers. Stricter regulations and enhanced monitoring of teas are needed to ensure food safety for tea consumption