By Allergen Bureau

Is ‘0.5 mg protein per 100 g of food’ a safe threshold for PAL?

Precautionary allergen labelling (PAL) such as “may contain traces of” is often used by food manufacturers but is generally unhelpful for consumers. Following widespread consultation, a voluntary labelling declaration has been proposed, to indicate that any unintended presence of an allergen is below a threshold of 0.5 mg protein per 100 g of food. Further assessment has been carried out to establish how safe this voluntary threshold may be for very sensitive consumers.

A group of experts from the Global Allergy and Asthma European Network (GA2EN) performed a systematic review to assess whether a fatal reaction to 5mg of protein or less has been reported, assuming that a maximum portion size of 1kg of a processed food exceeds any meal and therefore offers a sufficient safety margin.

The review found 210 studies in which one of the 14 major food allergens was reported to have caused a fatal or life-threatening anaphylactic reaction. None of the studies reported fatal reactions resulting from ingestion of less than 5 mg protein. However, in provocation studies and case reports, severe reactions to less than 5mg were reported for eggs, fish, lupin, milk, nuts, peanuts, soy, and sesame seeds.

The expert group concluded that unintended presence of the 14 major food allergens below 0.5 mg per 100 g is likely not to endanger most food allergic patients when a standard portion of food is consumed.

They propose use of the following statement for a voluntary declaration on processed food packages, at least as an interim step towards a legally binding solution: “This product contains [the named allergens in the list of ingredients]. It may contain traces of [other named allergens] at concentrations less than 0.5 mg per 100 g of this product”. This review is another piece of work that helps inform the science-based approach to allergenic thresholds.

Reference: Zuberbier et al. 2021 Allergy. DOI: 10.1111/all.15167. Available with Open Access.