Subcutaneous and intraperitoneal infusion of rats with hexavalent uranium: A pilot study

Exposure to soluble uranium (UO22+) in the nuclear fuel industry can be chemically toxic to the kidney. UO22+ accumulates in kidney and bone. The extent to which accumulated UO22+ affects toxicity is unknown. The specific aim of this study was to determine the optimum route of exposure (IP or SC) to uranyl nitrate using osmotic pumps. The criterion for selection was renal toxicity as related to the concentration of uranium in the kidney. Twelve male Long-Evans rats were divided equally between IP and SC treatment groups. All rats were given uranyl nitrate (9.3 μg U/day) and killed after either 7 or 14 days of continuous exposure, immediately following a 24-hour urine collection. Renal toxicity, measured as protein-to-creatinine ratio, was significantly greater in all exposed rats compared to controls at days 7 and 14. The IP but not the SC rats showed a significant increase in toxicity from day 7 to day 14. Data correlating the concentration of uranium with magnitude of effect will be presented. The increasing toxicity in the IP rats suggests that this route of exposure is more suitable than SC for conducting further experiments