912 THE CHEMICAL ENVIRONMENT

THE CHEMICAL ENVIRONMENT

2255. Iron dextran against indium teratogenesis

Ferm, V. H. (1970). Protective effect of ferric dextran on the embryopathic action of indium. Experientia 26, 633.

Zinc is known to give some protection against the teratogenic action of cadmium in hamsters (Ferm & Carpenter, Lab. Invest. 1968, 18, 429) while selenium protects against the teratogenic effects of both cadmium and arsenic (Holmberg & Ferm, Archs envir. Hlth 1969, 18, 873). Another example is now given of one element protecting against the terato- genic action of another. Ferric dextran was selected for this study because of its ability to suppress the liver injury and acute intoxication induced by indium, whose teratogenic action on hamster embryos has recently been demonstrated (Cited h7 F.C.T. 1971, 9, 747).

Pregnant hamsters received an intravenous dose of 0.5-2-0 mg indium nitrate/kg on day 8 of gestation either alone or in combination with iron dextran given intraperitoneally in a dose of 50 mg/animal. Examination of the embryos on day 14 or 15 of pregnancy revealed that iron dextran reduced the incidence of foetal deaths, resorption sites and limb mal- formations induced by indium, but did not appear to affect the type or severity of the malformations when these did occur. The percentage of embryos resorbed following treat- ment with 1 and 2 mg indium nitrate/kg was reduced from 51 and 69~ respectively to 5 and 2% by simultaneous iron dextran treatment, and the percentage of total limbs malformed at these two dose levels was reduced from 8 and 16% without to 0.5 and 3.6% with iron dextran.

2256. Cold comfort from strontium-90

Clarke, W. J., Palmer, R. F., Howard, E. B., Hackett, Patricia L. & Thomas, J. M. (1970). Strontium-90: Effects of chronic ingestion on farrowing performance of miniature swine. Science, N. Y. 169, 598.

In 773 female miniature swine fed through three successive generations with doses of strontium-90 (9°Sr) ranging from 1 to 3100/~c daily, there were no significant differences in litter size, birth weight and incidence of stillbirths between controls and animals receiving up to 625/~c 9°Sr daily. Dams ingesting 3100/~c 9°Sr daily failed to survive the gestation period. Body burdens of 9°Sr, determined by skeletal and soft-tissue radioanalysis, reached about ten times the daily intake in the F~ and F2 generations, the corresponding figure in the original dams being about 7.5. None of the F1 dams on 625/~c 9°Sr/day survived to produce a new generation. Haemopoietic disorders appeared in 14 of the original dams and in 55 of the F1 and F 2 animals, and seven animals in the groups receiving 125 or 625/zc 9°Sr/day developed bone tumours.

Significant radiation effects were thus seen in the animals exposed in this study, but there was no evidence of any effect on foetal or neonatal mortality. It appears that levels o f 9°Sr that would be high enough to influence foetal or neonatal mortality are lethal before gestation is achieved. The body burden of 9°Sr reached in some of the animals in this test represented more than l06 times the peak level of this radionuclide hitherto reported in the diet of Americans. It is concluded therefore that no effect on foetal or neonatal mortality in human populations is to be expected from current levels of exposure to 9°St.

2257. Acrylamide gets on your nerves!

Fullerton, Pamela M. (1969). Electrophysiological and histological observations on peri- pheral nerves in acrylamide poisoning in man. J. Neurol. Neurosurg. Psychiat. 32, 186.