Survey of Isothiazolinones and Other Preservatives in Household Wet Tissue Products in Japan

Abstract

Recently, many cases of contact dermatitis due to isothiazolinone preservatives in several types of household products used for cooling the body have been reported. As a result, the concentrations of isothiazolinone preservatives in these products were investigated. However, concentrations of isothiazolinone preservatives in other types of household products have not been studied adequately. In this study, 19 preservatives (including isothiazolinones) in 32 wet tissue products were investigated because these products come in direct contact with the skin. 2-Methyl-4-isothiazolin-3-one (MI), 5-chloro-2-methyl-4-isothiazolin-3-one (CMI), and benzisothiazolin-3-one (BIT) were detected in 19 samples (0.46-48 µg/g-wet), 17 samples (trace amount [tr.]-52 µg/g-wet), and one sample (67 µg/g-wet), respectively. Five types of parabens were detected in 21 samples (tr.-834 µg/g-wet). 2-Bromo-2-nitropropane-1,3-diol (Bronopol), 3-iodo-2-propynyl N-butylcarbamate (IPBC), and phenoxyethanol were detected in 12 samples (4.7-254 µg/g-wet), 11 samples (tr.-62 µg/g-wet), and 4 samples (65-1159 µg/g-wet), respectively. The concentration levels of isothiazolinone preservatives detected in this study perhaps induce allergic contact dermatitis in patients who are already sensitive to these preservatives. However, only 3 products described the use of isothiazolinone preservatives and a cautionary note about the possibility of contact dermatitis due to isothiazolinone preservatives was not provided. We also found that preservatives detected in the samples were different from those indicated on the product (in some cases, name of preservatives were not indicated at all). The use of such products may expose consumers to the risk of contact dermatitis; moreover, when contact dermatitis occurs, the identification of the substance that causes it may be delayed. Therefore, it is desirable that manufacturers provide information about the components of wet tissue products on the product labels.