Scientific Opinion on the toxicological evaluation of phenol

EFSA was asked by the German Federal Institute for Risk Assessment (BfR) to re-evaluate the TDI for phenol of 1.5 mg/kg bw/day, since this value is within the same dose range which was reported to be associated with some haematotoxic and immunotoxic effects in an oral study on phenol. The Panel comprehensively reviewed the available toxicological studies, mainly those using an oral route of exposure. The CEF experts did not consider immunotoxicity as a suitable endpoint on which to base a new TDI for phenol, given the study limitations and the lack of confirmation of phenol-induced immunotoxic effects in other studies. The Panel considered a gavage developmental toxicity study and an oral two-generation reproduction toxicity study as the two most robust toxicity studies, and performed a dose-response analysis of these data using the benchmark dose (BMD) approach. The lower 95 % confidence bound (one-sided) of the BMD, denoted BMDL, was then taken as the reference point. The lowest reference point for deriving a health based guidance value was provided by the BMDL₁₀ of 52 mg/kg bw/day for reduced maternal body weight gain from a developmental toxicity study where rats were exposed to phenol by gavage from gestational day 6 to 16. The CEF Panel set a TDI for phenol to 0.5 mg/kg bw/day, by applying a standard uncertainty factor of 100 (for inter- and intra-species differences) to this BMDL₁₀ value. The Panel did not assess the hazards related to the possible oxidation products of phenol, e.g. quinones/hydroquinones. Therefore, the above TDI only covers phenol. Exposure to phenol may occur via sources other than food contact materials, e.g. flavourings, smoke flavourings, traditionally smoked foods, floor waxes, cosmetics, disinfectants, etc.. The European Commission may wish to take note of all these sources of exposure if setting a restriction for phenol in food contact materials.