Determination of 1,4-dioxane in household detergents and cleaners

A possible human carcinogen, 1,4-dioxane, was investigated as to its concentration levels in household detergents and cleaners currently sold in Japan. A solid-phase extraction combined with stable isotope dilution and gas chromatographic/mass spectrometric determination was evaluated for the determination of 1,4-dioxane in household products. The evaluation of the method was performed using a recovery study of 1,4-dioxane-d8 from detergent and cleaner samples. The mean overall recovery and relative standard deviation were 78 and 15%, respectively. The limit of quantitation was 0.05 mg/kg. This method was satisfactorily applied to the determination of 1,4-dioxane in household products. 1,4-Dioxane was detected in 40 out of the 51 investigated samples. The concentrations ranged from 0.05 to 33 mg/kg, and the mean was 2.7 mg/kg. The mean of the products that included anionic surfactants, i.e., alkylpoly(oxyethylene)sulfates, was 7.2 mg/kg, which was higher than the 0.39 mg/kg mean for the other surfactants. Moreover, the 1,4-dioxane load/person was estimated to be 0.061 mg/day/person in Japan, which was 27% of the load from the domestic effluent.