On May 24, 2017 the European Food Safety Authority’s (EFSA) Panel on Food Contact Materials, Enzymes, Flavorings and Processing Aids (CEF Panel) published a scientific opinion on the safety assessment of the substance phosphorous acid, mixed 2,4-bis(1,1-dimethylpropyl)phenyl and 4-(1,1-dimethylpropyl)phenyl triesters (CAS 939402-02-5) for use in food contact materials (FCMs). The applicant requested an increase of the specific migration limit (SML) of the substance, from 5 mg/kg food to 10 mg/kg food, providing new toxicological studies in support of the request. The CEF Panel informed that the substance had already been evaluated in 2011 for its use as an antioxidant in all polymers, and that an impurity and hydrolysis product, 2,4-di-tert-amylphenol (CAS 120-95-6), has been reevaluated in 2015 (FPF reported). “The final plastics containing the antioxidant are intended to come into contact with all types of food for short term contact at high temperatures and long term storage at or below room temperature,” the CEF Panel explained.
Three new in vitro mutagenicity assays on the substance’s oxidation products support the 2011 conclusion that there is no concern for genotoxicity. A new toxicokinetic study supports the 2011 consideration that the substance does not accumulate. Further, a new delayed neurotoxicity study on a structurally related substance, phosphorous acid, tris (2,4-di-tert-butylphenyl) ester (CAS 31570-04-4), showing no neurotoxicity in hens, supports the 2011 conclusion that there is no concern for neurotoxicity. According to a new two-generation reproduction toxicity and prenatal developmental toxicity study on the substance, a new subchronic toxicity study on the substance’s oxidation products, as well as a two-year oral toxicity study on the structurally related substance, the lowest no observed adverse effect level (NOAEL) was determined to be 58–147 mg/kg bodyweight per day. The CEF Panel noted that “compared to the requested increase of the migration limit, this gives an acceptable margin of safety of 348.” Therefore, the CEF Panel concluded that increasing the SML of the substance from 5 to 10 mg/kg food is safe for consumers.