Arsenic, Germanium, Tin and Vanadium in Mice: Effects on growth, survival and tissue levels

Abstract

Certain trace elements found in the human environment may produce adverse biological effects when fed in small amounts to rats and mice for their lifetime. Others may be inert or have favorable actions. Mice numbering 643 were fed a diet of rye, corn oil and dried skim milk containing small amounts of arsenic, germanium and tin and larger amounts of vanadium, in an environment designed to exclude trace contaminants. Groups of 52 to 108 or more divided as to sex were given 5 ppm of these elements as arsenite, germanate, vanadyl or stannous ions in drinking water from weaning until natural death. Chromium (1 ppm) was added to the water of those given arsenic and germanium and their controls. No element but chromium affected growth. Median life spans and longevity of the oldest 10% of males given germanium and of both sexes given arsenic were somewhat shortened. This innate toxicity was not observed in animals given tin and vanadium. All elements accumulated in one or more organs, germanium and tin in spleen with age. No element was carcinogenic. Life-term exposures of animals to trace elements may show inherent toxicities at levels tolerable to young animals.