The effect of volatility on percutaneous absorption

Abstract

Introduction: Topically applied chemicals may volatilize, or evaporate, from skin leaving behind a chemical residue with new percutaneous absorptive capabilities. Understanding volatilization of topical medications, such as sunscreens, fragrances, insect repellants, cosmetics and other commonly applied topicals may have implications for their safety and efficacy. Methods: A systematic review of English language articles from 1979 to 2014 was performed using key search terms. Articles were evaluated to assess the relationship between volatility and percutaneous absorption. Results: A total of 12 articles were selected and reviewed. Key findings were that absorption is enhanced when coupled with a volatile substance, occlusion prevents evaporation and increases absorption, high ventilation increases volatilization and reduces absorption, and pH of skin has an affect on a chemical's volatility. The articles also brought to light that different methods may have an affect on volatility: different body regions; in vivo vs. in vitro; human vs. animal. Conclusions: Data suggest that volatility is crucial for determining safety and efficacy of cutaneous exposures and therapies. Few articles have been documented reporting evaporation in the context of percutaneous absorption, and of those published, great variability exists in methods. Further investigation of volatility is needed to properly evaluate its role in percutaneous absorption.

• Dermatology
• efficacy
• evaporation
• exposure
• pharmacology
• safety
• toxicity

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.