Appropriateness to set a group health based guidance value for T2 and HT2 toxin and its modified forms

Abstract

The EFSA Panel on Contaminants in the Food Chain (CONTAM) established a tolerable daily intake (TDI) for T2 and HT2 of 0.02 lg/kg body weight (bw) per day based on a new in vivo subchronic toxicity study in rats that confirmed that immune-and haematotoxicity are the critical effects of T2 and using a reduction in total leucocyte count as the critical endpoint. An acute reference dose (ARfD) of 0.3 lg for T2 and HT2/kg bw was established based on acute emetic events in mink. Modified forms of T2 and HT2 identified are phase I metabolites mainly formed through hydrolytic cleavage of one or more of the three ester groups of T2. Less prominent hydroxylation reactions occur predominantly at the side chain. Phase II metabolism involves conjugation with glucose, modified glucose, sulfate, feruloyl and acetyl groups. The few data on occurrence of modified forms indicate that grain products are their main source. The CONTAM Panel found it appropriate to establish a group TDI and a group ARfD for T2 and HT2 and its modified forms. Potency factors relative to T2 for the modified forms were used to account for differences in acute and chronic toxic potencies. It was assumed that conjugates (phase II metabolites of T2, HT2 and their phase I metabolites), which are not toxic per se, would be cleaved releasing their aglycones. These metabolites were assigned the relative potency factors (RPFs) of their respective aglycones. The RPFs assigned to the modified forms were all either 1 or less than 1. The uncertainties associated with the present assessment are considered as high. Using the established group, ARfD and TDI would overestimate any risk of modified T2 and HT2.

Human and animal dietary exposure to T‐2 and HT‐2 toxin

“…Table 6 summarises the range of average and 95th percentile acute exposures to the sum of T2 and HT2 across different age classes and dietary surveys. Information is also given on the percentage of subjects above the ARfD in all the different iterations (n = 1,000); an ARfD of 300 ng/kg bw per day was established in the 2017 EFSA CONTAM opinion (EFSA CONTAM Panel, 2017). Detailed average and 95th percentile acute exposure estimates for each dietary survey across age classes with their corresponding confidence intervals (2.5th and 97.5th percentiles) are described in Appendix G, Table G.9.…”

“…In 2017, EFSA published a scientific opinion on the appropriateness to set a group health-based guidance value (HBGV) for T2 and HT2 toxin and its modified forms (EFSA CONTAM Panel, 2017). For this opinion, the Panel reviewed new data on T2 and HT2 (published after the previous assessment) to confirm or revise the previously established TDI and also to set, if appropriate, an acute reference dose (ARfD).…”

A Simple and Specific Noncompetitive ELISA Method for HT-2 Toxin Detection

“…HT-2 toxin (HT-2) and T-2 toxin (T-2) are the most toxic trichothecene mycotoxins [1,2,3]. They occur in grains such as barley, wheat and oats, and are produced by Fusarium species [4].…”

Personal Care Products Are Only One of Many Exposure Routes of Natural Toxic Substances to Humans and the Environment

“…Mycotoxins, such as aflatoxins, trichothecenes, fumonisins, zearalenone (Figure 2), ochratoxins, and ergot alkaloids, produced by several species of the fungal genera Aspergillus, Fusarium, Penicillium, and Claviceps, are of concern for human and husbandry animal health. Consequently, many of them they are regulated by authorities with maximum levels (e.g., [66]), indicative levels (e.g., [67]), guidance values (e.g., [68]), or tolerable daily intake levels (e.g., [69]), and are regularly monitored in food and feed products. Traces of these compounds are excreted after consumption, and can enter surface water after only a partial elimination in WWTP [27,70,71].…”