This report is part of a study on skin pathology, blood levels and percutaneous toxicity after the epicutaneous administration of solvents. The method used for the study of percutaneous toxicity differentiated between different types of solvents, and between different applied volumes of the same solvent. Five solvents caused some mortalities (in declining order: 2-chloroethanol, 1,1,2-trichloroethane, ethyleneglycolmonobutylether, carbontetrachloride, and dimethylformamide). Four solvents--benzene, toluene, 1,1,1-trichloroethane, and trichloroethylene--did not cause mortality, but a statisically significant effect on weight gain was observed. For n-hexane the weight gain did not differ (P greater than 0.2) from that of the control animals exposed to distilled water. For comparison, the same amounts of the solvents were injected intraperitoneally. There was a fairly good agreement between intraperitoneal and percutaneous toxicity, but slight deviations were observed for carbontetrachloride and dimethylformamide.