THE American Contact Dermatitis Society awards the annual “honor” of “Allergen of the year” on an element, chemical or group of chemicals in order to “focus attention on the agents causing the most significant clinical effects” – and sulphites / sulphites received the dubious distinction for 2024.
Distinct from sulphates/sulphates, sulphites are perhaps more commonly known as preservatives and antioxidants in foods, and are designated as one of the 14 main food allergens or groups of food allergens reportable in the UK and the EU – the only chemical additive among the others. , all of which are foods – but they are not a recognized “major” allergen in the United States.
They are found in dried fruits, alcoholic beverages, fruit juices, pickled products and much more, and will be seen highlighted (usually in bold) in food ingredient lists, often near the end of the list. Sulfur dioxide is E220 and the different sulphites fall in the range E221 (sodium sulphite) to E228 (potassium acid sulphite).
But until now, awareness of the potential of sulfites as skin contact allergens in addition to food allergens has been underestimated, and they are not always used in the various standard skin test panels that dermatologists use to diagnose skin allergies caused by contact dermatitis.
They are commonly found in cosmetics, particularly in hair dyes and colorings (see my article ‘Sulfite-free hair dye” read more), styling products, makeup and tanning products — for example to prevent color oxidation, but also as general preservatives, including in other toiletries, and some medicines.
The mechanisms underlying dermatological and oral exposures and reactions to sulfites are different. So while dermatological reactions to cosmetic exposures can result in rashes, redness, and itching, often on the hands and face, food reactions can involve more typical allergy-type symptoms. like wheezing. That said, dietary exposures can also cause dermatitis symptoms on the lips and mouth.
If, despite food or skin allergy testing, you have persistent symptoms and you know you are exposing yourself to one of the sulfites, which may appear as follows:bisulfite‘Or’metabisulfite» as well as “sulfite” on cosmetic products, generally preceded by a mineral such as sodium, calcium or potassium. It may then be worth checking with your allergy consultants that these have been tested and ruled out as possible triggers.