Incidence and levels of Alternaria mycotoxins in spices and herbs produced worldwide and commercialized in Lebanon

Abstract

The emerging Alternaria mycotoxins tenuazonic acid (TeA), alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT) and tentoxin (TTX) are not yet regulated worldwide awaiting for more data on their toxicity and natural occurrence. A total of 131 samples of spices (94) and herbs (37) were collected in Beirut (Lebanon) markets and analysed for TeA, AOH, AME, ALT and TTX by using a UPLC-MS/MS method based on ‘extract, dilute and shoot’ approach. High percentage (89%) of samples were contaminated by 1–5 mycotoxins whereas 14% of samples were contaminated with a mixture of TeA, AOH, AME and TTX. TeA was the predominant mycotoxin with the highest percentages of positive samples (76%), followed by AME (46%), TTX (37%), AOH (34%) and ALT (5%) with overall mean/max levels of 2453.2/106792.8, 17.1/306, 14.8/179.4, 35.0/636.4 and 2.8/22.1 μg/kg, respectively (middle bound approach). Higher percentage of positive samples and mean mycotoxin levels were observed in spices as compared to herbs. The spices with higher levels of mycotoxin contamination were, in descending order, red chili, paprika, caraway, coriander seeds, onion powder, white pepper and garlic powder whereas within the herbs they were corn silk, violets and marjoram. Based on the mean levels of TeA measured in different spices and herbs, the daily consumption of >3.3 g red chili, >3.7 g paprika, >16.7 g caraway or >36 g of corn silk will exceed the threshold of toxicological concern (TTC) of TeA (1,500 ng/kg bw per day). For AOH or AME the TTC (2.5 ng/kg bw/day) will be exceeded by a daily consumption >0.5 g of white pepper, >0.9 g of onion powder, > 1.4 g of garlic powder, >1.7 g of black pepper, >1.9 g of sage, >3.3 g of violets or > 4.4 g of thyme leaves. This study provide large information on the natural occurrence of Alternaria mycotoxins in spices and herbs useful for the human exposure assessment and future regulation.