[en] Stannous chloride was injected by oral (IG), intraperitoneal (IP) and intravenous (IV) routes into mice, rats and African white-tailed rats and by IG and IV routes into monkeys and dogs. Less than 5% was absorbed from the gut. There was much similarity in retention patterns following parenteral administration, and the small amount absorbed from the gut in conjunction with the discontinuous nature of fecal excretion resulted in similar patterns after ingestion of tin. Bone was the chief site of tin deposition. The biological inertness of tin results in a low order of toxicity. The radiation protection guides set by the International Commission on Radiological Protection in 1960 appear to be adequate in view of the data presented. (author)