In vitro skin permeation of potassium hexachloroplatinate and a comparison with potassium tetrachloroplatinate

Halogenated platinum salts are known respiratory sensitizers in the workplace, and occupational exposure to platinum via the respiratory system and skin has been reported. The aim of this study was to compare the permeability and skin retention of potassium hexachloroplatinate to previously published data of potassium tetrachloroplatinate. Experiments were performed using female Caucasian skin and Franz diffusion cells with the application of 0.3 mg Pt/mL in the donor solution for 24-h. After 8-h of exposure, 1.87 ng/cm² of Pt was detected in the receptor solution with exposure to potassium hexachloroplatinate, whereas 0.47 ng/cm² was detected with exposure to potassium tetrachloroplatinate. After 24-h of exposure the Pt retention in the skin was 1861.60 ng/cm² and 1486.32 ng/cm² with exposure to potassium hexa- and tetrachloroplatinate respectively. The faster rate of Pt permeation from exposure to potassium hexachloroplatinate was confirmed by the flux and permeability coefficient values. The results indicate a higher permeability and skin retention of Pt when exposed to potassium hexachloroplatinate, confirming a higher risk associated with occupational exposure to this platinum compound relative to potassium tetrachloroplatinate.