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FACTS reports now include allergen threshold levels
March 2009

The draft South African labelling regulations (Anon., 2007) require the declaration of any of the "common food allergens" contained in a food product on the product label. These common allergens include cow’s milk, egg, fish, crustaceans and molluscs, soy, peanuts, tree nuts and certain grains. However, the issue of cross-contamination with these allergens, and the doses of allergens that can cause a reaction, needs to be recognized by the food industry to prevent a possible fatal reaction from occurring.

How have threshold levels been determined?
As individuals with food allergies differ in their degree of sensitivity to specific allergenic foods, attempts have been made to determine threshold doses for the major food allergens. The basic concept of establishing allergen thresholds is that if a Lowest Observed Adverse Effect Level (LOAEL) and No Observed Adverse Effect Level (NOAEL) are identified, then the food industry may target their processes to achieve these levels. There is currently limited consensus in the scientific literature regarding thresholds for the common food allergens. For this reason, the US FDA Threshold Working Group conducted an extensive review of the published literature containing dose-response data from double-blind placebo controlled food challenges (DBPCFC) from November 2004 to April 2005. In 2006, this group summarised the threshold data for some of the common food allergens as follows:

FACTS has included these summarised threshold levels in all allergen test reports in order to assist the food industry in assessing the risks of allergen cross contamination and to gauge the need for allergen precautionary labelling. The threshold values are a simplistic view of the problem, but FACTS is always available to put these in perspective based on the product, the matrix, and other relevant issues.

How can allergen thresholds be useful?
A soy drink was found to be contaminated with 20 ppm milk protein using an ELISA detection method. According do the published threshold LOAEL data summarised by the US FDA Threshold Working Group, consumption of as little as 0.36 mg milk protein could elicit mild, objective symptoms in highly sensitive individuals. Consumption of just 18 g (approximately two sips) of this soy drink could contain 0.36 mg milk protein, and thus be sufficient to elicit a reaction in a highly milk allergic person. Thus, since a serving of such a drink would normally be around 200 g, this product is likely to pose a considerable threat to milk allergic patients. The source of the contamination should be identified and the problem rectified, and if it cannot be, then precautionary labeling is highly advisable.

References:
Anonymous (2007). Foodstuffs, Cosmetics and Disinfectants Act, 1972 (Act 54 of 1972). The draft South African regulations relating to the labelling and advertising of foodstuffs, Government notice R.642. Government Gazette No. 30075, 69-145.
FDA (2006). Approaches to Establish Thresholds for Major Food Allergens and for Gluten in Food. Available at: www.cfsan.fda.gov/~dms/alrgn.html