Permeability of human skin to selected anions and cations--in vitro studies.

Among the many factors influencing the human body every day, metal cations and anions are some of the most important and are constantly present in atmospheric fallout. Some of them such as sulfate or nitrate anions along with different detergents may cause pathological changes within the skin. The aim of this study was to estimate whether sulfate (SO4(2-)) and nitrate anions (NO3-) as well as metal cations, magnesium (Mg2+) and calcium (Ca2+) are able to pass through isolated patches of human skin and to investigate the dynamics of ion diffusion. Concentrations of the substances corresponded to those observed in the atmospheric fallout in two regions of Poland with low (Białowieza) and high (Katowice) pollution rate. Ion chromatography method was used to determine cations and anions levels. In vitro, we found human skin to be permeable to magnesium and calcium ions as well as sulfate and nitrate anions at concentrations observed in the atmospheric fallout in two regions of Poland having different levels of pollution. Diverse influence of sodium lauryl sulfate (SLS) detergent on the grade of metal ion permeability (acceleration in the first 10 hours of experiment) and anion permeability (lack of SO4(2-) influence) suggest the presence of different routes of ions penetration through the skin. It is also supported by different transportation characteristics of individual ions through the skin over time.