Reproductive Toxicity Screen of Liquid Propellant XM46 Administered in the Drinking Water of Sprague-Dawley Rats.

Liquid propellant XM46 is being considered as a replacement for solid propellants, both as part of a regenerative injection gun system as a working fluid in an electrothermal gun system. The XM46 formulation contains hydroxylammonium nitrate, triethanolammonium nitrate, and water. Male and female Sprague-Dawley rats received XM46 drinking water containing 2.0, 1.0, 0.2, or 0.0 g XM46/L throughout a 90-day study. Mating occurred following 14 days of treatment. One half the male rats per group were necropsied after 28 days of treatment, the remaining males and all dams were necropsied following 90 days. No mortality occurred in any of the parental animals during the study. The study did not produce any adverse effects on reproduction or litter parameters. Hemolytic anemia and methemoglobinemia were common findings in both sexes of rats. Splenomegaly was found in both sexes; in male rats, as early as 28 days. Exposure via drinking water containing XM46 for 90 days did not result in any decrease in reproductive performance in male or female rats, but it did result in clinical signs of hemolytic anemia at doses as low as 17 mg/kg/day.