Percutaneous absorption of hexachlorophene in the rat.

[¹⁴C]-hexachlorophene was applied to intact, clipped skins of adult rats in four different solvents and an aqueous detergent solution. As much as 55% of the applied radioactivity was absorbed through the skin in a 24-hr period. Dimethyl sulfoxide enhanced absorption of the germicide to the greatest extent and aqueous sodium lauryl sulfate (1%, $\text{w}\text{v}$) was the least effective. With both adult and weanling rats, the first measurable amount of radioactivity appeared in the venous blood in less than 1.5 hr, and maximum values were attained 12 hr after topical application of [¹⁴C]hexachlorophene. Approximately 27% of the applied radioactivity remained bound to the skin after 4 and 24 hr and was not removed by washing with acetone. Distribution of radioactivity in rats 8 and 24 hr after topical application of [¹⁴C]hexachlorophene was similar in weanling and adult rats. Most of the absorbed radioactivity appeared in the plasma, liver, small intestine, caecum, stomach, kidney, urine, and feces.