Appropriateness to set a group health based guidance value for nivalenol and its modified forms

Abstract

The EFSA Panel on Contaminants in the Food Chain ( CONTAM) reviewed new studies on nivalenol since the previous opinion on nivalenol published in 2013, but as no new relevant data were identified the tolerable daily intake ( TDI) for nivalenol ( NIV) of 1.2 μg/kg body weight (bw) established on bases of immuno‐ and haematotoxicity in rats was retained. An acute reference dose ( ARfD) of 14 μg/kg bw was established based on acute emetic events in mink. The only phase I metabolite of NIV identified is de‐epoxy‐nivalenol ( DE‐ NIV) and the only phase II metabolite is nivalenol‐3‐glucoside ( NIV3Glc). DE‐ NIV is devoid of toxic activity and was thus not further considered. NIV3Glc can occur in cereals amounting up to about 50% of NIV. There are no toxicity data on NIV3Glc, but as it can be assumed that it is hydrolysed to NIV in the intestinal tract it should be included in a group TDI and in a group ARfD with NIV. The uncertainty associated with the present assessment is considered as high and it would rather overestimate than underestimate any risk.