Children with atopic dermatitis and frequent emollient use have increased urinary levels of low-molecular-weight phthalate metabolites and parabens.

BACKGROUND: Parabens may be added to cosmetic and personal care products for preservation purposes. Low-molecular weight (LMW) phthalate diesters function as plasticizers, fixatives or solvents in such products, but may also be found in small quantities as contaminants from plastic containers.

OBJECTIVE: To evaluate the association between emollient use, atopic dermatitis and FLG mutations, respectively, with urinary concentrations of phthalate metabolites and parabens in Danish children.

METHODS: Eight hundred and forty-five Danish children 4-9 years of age were studied. Urinary concentrations of phthalate metabolites and parabens were determined, and children were genotyped for common FLG loss-of-function mutations. Information about atopic dermatitis and use of emollients was obtained from questionnaires completed by parents.

RESULTS: The prevalence of atopic dermatitis was 16.1%. Phthalate metabolite and paraben levels were generally higher in children with frequent use of emollients compared to uncommon users, reaching statistical significance for some LMW phthalates and parabens. While there was no association with common FLG mutations, children with atopic dermatitis had significantly higher urinary levels of one LMW phthalate and two parabens, respectively, when compared to children without atopic dermatitis.

CONCLUSION: Emollient use and atopic dermatitis were associated with modestly increased internal LMW phthalate and paraben exposure in 4-9 year old children. It is unknown whether the difference is explained by increased use of the specific emollients that are used to treat pruritic and inflamed skin, and/or whether the impaired skin barrier allows chemicals to penetrate more easily. Moreover, the putative toxicological burden is unknown.