Inorganic tin in the diet affects the femur in rats

The effects of dietary levels (10, 50, 100 and 250 ppm tin) of stannous chloride on the femur were studied for 90 days on weanling male rats. The 100 and 250 ppm tin (Sn) caused significant decreases in serum calcium (Ca) and serum inorganic phosphorus (P), Ca content in the femoral diaphysis and epiphysis, and acid phosphatase activity in the femoral epiphysis. 50 ppm Sn produced significant reduction of serum Ca concentration and Ca content in the femoral epiphysis. These significant decreases were not observed with 10 ppm Sn. These results suggest that the maximal allowable concentration of inorganic Sn contained in a diet would be less than 50 ppm Sn.