Domestic Cleaning Products and the Risk of Dermatitis: A Prospective Cohort Study in Chinese Primary School Children

Abstract

Introduction: The effects of domestic cleaning products on childhood dermatitis lacks of convincing and conclusive evidence. This study aims to investigate usage of domestic cleaning products and their association with contact and atopic dermatitis in Hong Kong primary school children. Methods: A total of 2299 students from a Hong Kong prospective cohort study successfully accomplished the baseline and the follow-up survey. Among them, 1839 students who did not have contact dermatitis and atopic dermatitis in the baseline survey were included in this analysis. Self-administered questionnaires were completed by parents/guardians to collect information on contact and atopic dermatitis, exposure to household chemical cleaning products and potential confounders. Total chemical burden (TCB) score was calculated based on the total exposure time to 14 chemical cleaning products. Principle component and factor analysis was used to extract the patterns of usage of domestic cleaning products. Logistic regression was performed to calculate relative risk (RR) with 95% confidence intervals (CI) adjusting for potential confounders. Results: The mean (S.D.) age was 10.1 (0.9) years and the body mass index was 17.9 (3.4) kg/m2. 48.9% of the participants were boys. The TCB score was grouped into tertiles, and the participants with the highest tertile of TCB had a significantly higher risk of contact dermatitis (RR: 1.58, 95% CI: 1.05 – 2.55) compared with those with the lowest tertile of TCB, whereas the association for the atopic dermatitis (RR: 1.11, 95% CI: 0.69 – 1.80) was not significant. Four domestic cleaning products usage patterns were defined but none was significantly associated with the risk of neither contact nor atopic dermatitis. Conclusions: Domestic cleaning products usages were associated with an increased risk of contact dermatitis in primary school children. Our findings suggest that it is necessary to replace them with cleaning products with fewer chemicals.