Subchronic feeding study of antimony trioxide in rats.

Diets containing antimony trioxide were fed to male and female Wistar rats of the Alpk:APSD strain over 90 days. Dose levels were 0 (control), 1000, 5000 and 20,000 ppm (equivalent to mean daily doses of 84, 421 and 1686 mg kg(-1) in males and 97, 494 and 1879 mg kg(-1) in females). There was no effect of compound on growth or growth rate, food consumption or clinical signs. Minor changes in haematology and urine biochemistry were considered incidental to treatment. Small reductions in plasma alkaline phosphatase activity and increases in aspartate aminotransferase activity at the high dose, together with a small (ca. 10%) increase in liver weight, could be indicative of a minor effect on the liver, but in the absence of any histological effects these changes are also considered incidental to treatment. This study confirms the inert nature of antimony trioxide.