Alternaria toxins and conjugates in selected foods in the Netherlands

- Tenuazonic acid (TeA) occurs at high levels in sunflower seeds and dried figs in 2014.
- Processing of sunflower seeds to obtain oil or paste may degrade TeA.
- Alternariol (AOH), alternariol methyl ether (AME) and TeA occur in tomato products.
- The consumption of high amounts of tomato products may pose a risk for health in the Netherlands.
- Conjugates of Alternaria toxins could not be found at levels higher than 2.5 μg/kg.

A survey on Alternaria toxins in the food categories dried figs (n = 14), sunflower products (n = 24) and tomato products (n = 43) was carried out in the Netherlands on samples collected in retail stores in autumn 2014. The occurrence data from this survey confirmed the previously reported data of a pilot survey in 2013, with tenuazonic acid being an ubiquitous Alternaria toxin in dried figs (100% of the samples), sunflower seeds (80% of the samples) and tomato products (60% of samples) at relatively high concentrations, up to 1728 μg/kg in dried figs and 1350 μg/kg in sunflower seeds. Despite the occurring of high concentrations of tenuazonic acid in sunflower seeds and figs, it is unlikely that the population in the Netherlands is exposed to levels of concern. Alternariol was detected in 27% of the tomato products ranging from LOQ (2 μg/kg) up to 26 μg/kg, while alternariol monomethyl ether was present in 7% of the tomato products. In the worst case situation, consumption of these products may result in exposure at levels above the threshold of toxicological concern of 2.5 ng/kg body weight/day for alternariol. None of seven conjugates of Alternaria toxins was detected above the limit of quantification (LOQ) of 2.5 μg/kg.