CONTACT ALLERGENIC ACTIVITY OF TWEEN(R)-80 BEFORE AND AFTER AIR EXPOSURE

Tween 80 is an ethoxylated hydrophilic non-ionic surfactant, which is used for the preparation of oil-in-water emulsions in pharmaceutical p roducts, cosmetics, and industrial detergents. Ethoxylated surfactants are polyethers and are thus easily oxidized by atmospheric oxygen to a variety of hydroperoxides, peroxides and carbonyl compounds. The aim was to investigate the formation of oxidation products and the allerg enic potential of Tween 80 before and after air exposure. The formatio n of peroxides and formaldehyde was followed with chemical analyses du ring air and pure oxygen exposure of water solutions of Tween 80 of te chnical quality. A complex mixture of compounds was formed when Tween 80 was oxidized. Formaldehyde was detected in amounts that may be elic iting in allergic individuals. Acetaldehyde was identified in Tween 80 before oxygen exposure, whereafter the amount gradually decreased. Th e contact allergenic activity was determined in experimental sensitiza tion studies in guinea pigs. Non-oxidized as well as oxidized Tween 80 of technical quality showed allergenic activity. The results indicate that allergens are present in Tween 80 before oxidation and that new allergens are formed in the oxidation process. No obvious dose-respons e relationship was found in the sensitization studies. The possibility that allergenic compounds can be formed during storage and handling o f products containing ethoxylated surfactants should be taken into con sideration. (C) Munksgaard, 1997.