Survey of deoxynivalenol and its conjugates deoxynivalenol-3-glucoside and 3-acetyl-deoxynivalenol in 374 beer samples.

Beer is one of the most popular beverages worldwide. Malted cereal grains are among the basic ingredients and hence mycotoxin contamination might occur. Previous studies reported the presence of the Fusarium mycotoxins deoxynivalenol (DON) and 3-acetyl-deoxynivalenol (3ADON), as well as of the masked mycotoxin deoxynivalenol-3-glucoside (D3G) in beer. In the present survey, 374 beer samples from 38 countries with a focus on Austrian (156) and German (64) beers were analysed for the presence of D3G, DON and 3ADON. Beers were assigned to the following six categories: pale (217), wheat (46), dark (47), bock (20), nonalcoholic beers (19) and shandies (25). In total, 348 and 289 beers (93 and 77%, respectively) contained D3G and DON at the levels above the limit of detection, whereas 3ADON was not detected in any of the samples. Average concentrations of all beers were 6.9 µg L(-1) for D3G and 8.4 µg L(-1) in the case of DON. Nonalcoholic beers and shandies showed the lowest contaminations, 1.5 and 3.2 µg L(-1) for D3G and 2.7 and 4.4 µg L(-1) for DON, respectively. In bock beers characterised by a higher gravity, a significant trichothecene load of 14.8 µg L(-1) D3G and 12.4 µg L(-1) DON was found. The highest contamination (81 µg L(-1) D3G, 89 µg L(-1) DON) was detected in a pale beer from Austria, underlining the importance of this study for food safety. The molar D3G to DON ratio ranged between 0.11 and 1.25 and was 0.56 on average. Concluding, the average contamination of beer is not of toxicological concern for moderate beer drinkers. However, in the case of heavy beer drinkers, beer consumption may considerably contribute to the overall intake of DON, which might even lead to exceeding the maximum tolerable limits established for this Fusarium toxin.