Fertility was evaluated in groups male Sprague-Dawley rats (15/group) receiving whole body exposure to acetone cyanohydrin at nominal concentrations of 10, 30 or 60ppm in a dynamic air flow chamber, 6hrs/day, 5days/week for 69 days (48 exposure days). After 48 exposure days, males were mated to three untreated females, exposure continued until the day of the last mating opportunity (58 exposure days). Mated females were sacrificed at mid-term (gestation days 13-15). There was no effect of treatment for all males as indicated by mortality, mean body weights, clinical observations and necropsy observations. The number of live implants and pre- and postimplantation losses were comparable for all females mated with untreated and treated males.