1-amino-3-chloro-2-propanol (CL 88236) was administered by oral gavage for 12 consecutive weeks to rats at dose levels of 50, 250 and 500 mg/kg/day. All levels gave rise to toxicological effects. Epididymal necrosis and/or atrophy of the seminiferous epithelium was found for some males with each dose of CL 88236. The kidney and liver weights of male and female rats given CL 88236 were higher than control values but no histological changes were found in these organs.