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The skin distribution and percutaneous absorption of [14C]hexachlorophene have been studied in guinea pigs after washing with dishwashing detergent, a toilet soap and a toilet soap containing non-soap detergent (NSD). The deposition in human skin of [14C]hexachlorophene from the toilet soap and NSD bar has also been measured. The excretion of [14C]hexachlorophene by rats after intraperitoneal injection has been investigated. Most of the hexachlorophene applied to guinea pig skin in the dishwashing detergent was removed in the rinse water. Autoradiography of skin sections showed that, of the [14C]hexachlorophene remaining in the skin, most was deposited on the stratum corneum from the dishwashing liquid, the toilet soap and the NSD toilet bar. As depth into the skin increased, the amount of germicide present in successive sections rapidly decreased. The main differences between the autoradiograms was that the [14C]hexachlorophene from the dishwashing detergent and the NSD bar was seen in the hair follicles as well as penetrating transepidermally whereas only transepidermal penetration was seen when the [14C]hexachlorophene was applied in the toilet soap. Approx. 12 μg/20 cm2 skin was deposited from the dishwashing liquid and approx. 12 μg/20 cm2 skin from the NSD bar. The amount of hexachlorophene absorbed into the carcass through the 20 cm2 skin washed with the NSD toilet bar was approx. 15 μg. From these figures it was calculated that a single washing of the entire human skin surface with the NSD bar containing 1% hexachlorophene could expose man to a maximum dose of 0.36 mg/kg. In human skin, the amount of [14C]hexachlorophene from a single wash varied from 0.1–0.7 μg/cm2, depending upon the nature of the soap vehicle. Repeated washing increased the deposition from 0.1–0.9 μg/cm2. Virtually all [14C]hexachlorophene disappeared from the skin in the 2 days after treatments.