PERCUTANEOUS-ABSORPTION OF ORGANIC-SOLVENTS DURING INTERMITTENT EXPOSURE IN GUINEA-PIGS

Skin absorption under intermittent exposure of guinea pigs to n-butano l, toluene, 1,1,1-trichloroethane was studied. Groups of guinea pigs w ere exposed to test organic solvents for 1 min at 30-min intervals dur ing 4 h, in all 8 exposures, Skin absorption of solvent was assessed b y following the concentration of solvent in the blood. This intermitte nt exposure was compared to continuous exposure over 4 h, Absorption o f toluene and 1,1,1-trichloroethane was low, but a considerable amount of butanol was absorbed through the skin on intermittent exposure. A typical serrated absorption profile was seen for butanol that was less pronounced for toluene and 1,1,1-trichloroethane. The absorption of b utanol was highest at the end of the exposure period. The differences in absorption profiles may be due to the differences in vapour pressur e in the solvents in association with the animal method used, The amou nt absorbed varied inversely with vapour pressure, Hair stubble may ac t as a trap for solvents with low vapour pressure. Adequate ventilatio n reduces unoccluded skin absorption of volatile organic solvents.