Zirconium, Niobium, Antimony and Fluorine in Mice: Effects on growth, survival and tissue levels

Abstract

To evaluate innate effects of certain trace elements, 540 mice were fed a diet of rye, corn oil and dried skim milk containing moderate amounts of zirconium and niobium and no detectable antimony or fluorine, in an environment relatively free of trace contaminants. Groups of 108, divided as to sex, were given 5 ppm zirconium, niobate or antimony or 10 ppm fluoride in drinking water from weaning until natural death. Females given fluoride grew somewhat larger at older ages and both sexes survived as long as their controls. Inherent toxicity, manifest by decreased median life spans and longevity and by some suppression of growth of older animals, was observed in females given niobium and antimony. The feeding of niobium was associated with an increased incidence of hepatic fatty degeneration. No element was carcinogenic or tumorigenic. Fluoride did not accumulate in soft tissues, but increments of niobium and antimony were found. Zirconium occurred in both controls and experimental groups, and showed slight toxicity. Of 15 trace elements studied in this manner, chromium, fluorine and nickel showed no demonstrable innate toxicity, whereas tellurium, arsenic, tin and vanadium showed the most.