Effect of chelating agents on tissue distribution and excretion of strontium following semichronic strontium ingestion.

The effects of repeated ip administration of diethylenetriamine-pentaacetic acid (DTPA), ethylenglycol-bis-(-amino-ethlylether)-N,N'-tetraacetic acid (EGTA), Kryptofix 222, tartaric acid, and Kryptofix 5 on strontium (Sr) excretion and Sr levels in selected mouse tissues were investigated following semichronic strontium nitrate ingestion (284 mg/kg/day) for four weeks. Chelating agents were injected daily for five days at 1/4 of their respective LD50 in two equally divided doses. Only Kryptofix 5 significantly increased the amount of Sr excreted into urine, whereas none of the chelators enhanced the fecal Sr elimination. A significant decrease in the concentration of Sr in bone, the primary tissue of Sr deposition, was observed after treatment with EGTA. Under these experimental conditions, none of the chelators tested was able to remove significant amounts of Sr following Sr ingestion for four weeks.