Allergenic activity of an air‐oxidized ethoxylated surfactant

Abstract

Ethoxylated surfactants are used in household and industrial cleaners, topical pharmaceuticals, cosmetics and laundry products. Polyethers, e.g. ethoxylated surfactants and polyethylene glycols, are oxidized by atmospheric oxygen (autoxidized) when stored and handled. We have previously shown that a chemically well-defined non-ionic surfactant, the ethoxylated alcohol penta-ethylene glycol mono-n-dodecyl ether (C 12 E 5 ), forms a complex mixture of autoxidation products when exposed to air. Predictive testing in guinea pigs showed that the surfactant itself is a nonsensitizer, but that oxidation products formed are skin sensitizers. The aim of this study was to investigate the sensitizing capacity of a total oxidation mixture of C 12 E 5 obtained after autoxidation. The allergenic activity of different oxidation products is discussed as well as the clinical importance of the findings. This study shows that the non-ionic surfactant C 12 E 5 containing 20% oxidation products is a sensitizing mixture. The result accords with what is observed for other compounds that are unstable when in contact with air, e.g. limonene and linalool, major fragrance terpenes. Studies regarding the clinical relevance of our findings should be performed. However, it is already clear from this study that precautions must be taken in handling and storage of ethoxylated surfactants to avoid formation of allergenic mixtures.

Workgroup Report: Indoor Chemistry and Health

“…The use of cleaning products containing both terpenes and glycol ethers in the presence of O 3 can lead to oxidation of the glycol ethers via OH and perhaps NO 3 (Nazaroff and Weschler 2004); resultant products may include potentially allergenic peroxides and hydroperoxides (Karlberg et al 2003). Modeling indicates that when O 3 and NO 2 are present simultaneously, indoor NO 3 may be the dominant indoor oxidant; NO 3 levels as low as 1 ppt can compete effectively with O 3 and OH in oxidizing various terpenoids (Nazaroff and Weschler 2004).…”

Mechanisms of Air Oxidation of Ethoxylated Surfactants—Computational Estimations of Energies and Reaction Behaviors

“…[1,2] In previous experimental studies, [3] we have shown that autoxidation of nonionic alcohol ethoxylates generates products that are skin sensitizers. Specific oxidation products, like hydroperoxides, formaldehyde, ethoxylated aldehydes, and ethoxylated formates, have been identified in autoxidation mixtures of the pure ethoxylated alcohol pentaethylene glycol mono-n-dodecyl ether (C 12 E 5 ; Scheme 1a) used as reference surfactant.…”

“…Specific oxidation products, like hydroperoxides, formaldehyde, ethoxylated aldehydes, and ethoxylated formates, have been identified in autoxidation mixtures of the pure ethoxylated alcohol pentaethylene glycol mono-n-dodecyl ether (C 12 E 5 ; Scheme 1a) used as reference surfactant. [3] Two hydroperoxides were identified, namely, 1-hydroperoxy-3,6,9,12,15-pentaoxaheptacosan-1-ol (Scheme 1c) and 16-hydroperoxy-3,6,9,12,15-pentaoxaheptacosan-1-ol (Scheme 1d), the latter being the dominating hydroperoxide in the oxidation mixture. [8] The major oxidation product Keywords: allergens · autoxidation · density functional calculations · ethoxylated surfactants · radicals Abstract: Pathways for formation of previously observed autoxidation products of ethoxylated surfactants have been studied by DFT (B3LYP).…”

“…[4] Autoxidized C 12 E 5 was demonstrated to be allergenic in sensitization studies [3] and proved to have a significantly higher skin-irritating potential than the pure surfactant. [5] Of the products identified on autoxidation, all but ethoxylated formates (Scheme 1g) were shown to be contact allergens.…”

Respiratory System

“…Although both DEP and ragweed enhance ragweed-specifi c IgE, the combination of ragweed and DEP exposure produces a synergistic effect that increases ragweed-specifi c IgE production by 16-fold. [ 33 ] In one study, pure surfactant was found to show no allergenic activity. [ 32 ] Ethoxylated surfactants (ES) are used in household and industrial cleaners, laundry detergents, pharmaceuticals, and cosmetics.…”