In a subchronic toxicity study, male and female Wistar rats (10/sex/group) were dermally exposed to formamide at dose levels of 0, 300, 1000 or 3000 mg/kg/day over a period of 90 days. There were statistically significant differences between treated and control animals in the following: decreased food consumption (both sexes at high-dose level), decreased body weight gain (both sexes at high-dose level), appearance of an erythema of the skin followed by further symptoms including poor general condition, apathy, dyspnoea and staggering (both sexes at high-dose level, 55-58 days after beginning of the application), and marked signs of erythcythemia in the form of increased hemoglobin and erythrocyte counts (all treated males and high-dose females). There were other differences (statistical significance not reported) between treated and control animals in the following: increased hematocrit values and decreases in leucocyte and lymphocyte counts (mid- and high-dose males), increased mean cell volume (both sexes, mid- and high-dose groups), increased mean corpuscular concentration and creatinine values (both sexes, high-dose groups), and decreased platelets, total protein, albumin and glucose (high-dose males). No animal exhibited a value of 10% carboxyhemoglobin (limit of detection). One high-dose female, with prominent bleeding from stomach ulceration, was moribund at day 83 of the study. No histopathology results were reported.