AWWA JAW28447

In separate subchronic toxicity studies, male and female SpragueDawley rats received various dosages of chlorine, monochloramine, or chlorine dioxide in their drinking water for 90 consecutive days. None of the disinfectants caused premature death at any of the concentrations used. The highest dose of chlorine tested (250 mg/L) was concluded to be a no observable adverse effect level. At 200 mg/L (the lowest observable adverse effect level), monochloramine produced decreased body and organ weights in both sexes and a small decrease in red blood cell count and serum calcium in males. Chlorine dioxide produced dosage-related decreases in body and organ weight at concentrations as low as 25 mg/L, but its most significant toxic effect was the induction, at all concentrations, of nasal lesions. Includes 39 references, tables.