The skin is the body’s largest organ and serves as the primary barrier between internal systems and the external environment. PFAS exposure — through drinking water, food contact materials, and skin care products — has been linked to skin conditions including eczema, contact dermatitis, and impaired skin barrier function.
PFAS in Skin Care Products and Topical Exposure
Many cosmetics and personal care products historically contained PFAS as water-repellent, texture-enhancing, or long-wearing agents. Foundations, mascaras, lipsticks, sunscreens, and moisturizers have been found to contain PFAS in laboratory analyses. Regulatory scrutiny has increased, leading some manufacturers to reformulate, but PFAS remain in many products on the market.
Dermal absorption of PFAS from cosmetics is less efficient than ingestion but represents an additional exposure pathway. Frequent application of PFAS-containing products to large skin surface areas, particularly the face, contributes to cumulative exposure beyond what drinking water alone provides.
PFAS and Eczema
Atopic dermatitis (eczema) is characterized by skin barrier dysfunction, chronic inflammation, and immune dysregulation. PFAS may contribute to eczema through several pathways: immune disruption that promotes allergic sensitization, direct disruption of skin barrier proteins including filaggrin, and altered inflammatory signaling in skin tissue.
Several epidemiological studies have found higher rates of eczema diagnosis in children with greater PFAS exposures. A Norwegian birth cohort study found that prenatal PFAS exposure was associated with increased eczema risk in early childhood. Immune-suppressing and immune-dysregulating effects of PFAS likely contribute to these findings through different mechanisms.
Skin Barrier Function and PFAS
The skin barrier depends on proper expression and assembly of structural proteins including filaggrin, loricrin, and ceramides. PFAS have been shown in cell studies to disrupt the expression of these proteins, potentially impairing the skin’s ability to maintain hydration and exclude environmental allergens and irritants.
Impaired skin barrier function can create a vicious cycle: a compromised barrier allows greater penetration of PFAS from topically applied products while simultaneously making the skin more susceptible to irritants and allergens. This cycle may be particularly problematic in individuals with genetic predispositions to atopic conditions.
Water Quality and Skin Health
While shower and bath water represent a potential PFAS dermal exposure pathway, absorption through intact skin from water is generally lower than absorption from cosmetic products. Nonetheless, for individuals with eczema or compromised skin barriers, reducing PFAS in water used for bathing may reduce the total dermal PFAS burden.
For drinking and cooking water, reverse osmosis filtration removes PFAS before ingestion, reducing the systemic PFAS body burden that contributes to skin inflammation through immune and inflammatory pathways. Individuals with chronic skin conditions may benefit from comprehensive PFAS exposure assessment as part of their dermatological care.