Interactions Between Skincare Product Ingredients and the Skin Microbiome

Skin serves as a critical barrier between our bodies and the environment and the locus for a diverse and active microbial community. The composition and metabolic activity of the microbial community on the skin is presumably influenced by the local chemical environment, which includes natural skin lipids (e.g., squalene and sapienic acid), components of personal care products applied directly to skin, and semi-volatile organic compounds (SVOCs) that reach the skin through gas phase absorption, dust deposition, and direct contact with surfaces. Common semi-volatile ingredients in skin care products include phthalates, parabens, and UV blocking compounds (e.g., oxybenzone, octocrylene or homosalate).

The investigators have recently demonstrated a method of collecting chemicals from areas of skin with infrequent direct dermal contact using alcohol wipes to assess passive air to skin partitioning of both target and nontarget compounds (Garrido et al., in review). Low-volatility reaction products can accumulate in skin oils and act as skin irritants, with the potential of being absorbed into the bloodstream. With methods developed for chemical and microbiome sampling, the overall goal of the proposed research is to develop an understanding of the two-way interaction between organic chemicals on the skin and the composition of the skin microbiome.