Abstract
We have examined the influences of some radioactive substances, e. g., Ca45, Sr90, Fe5559, Ce137 and Fission product (P) upon the development, either culturing the amphibian eggs in the medium annexed with the radioisotopes or injecting these substances into the pregnant mouse. The development of the amphibian egg is most seriously affected when operated soon after the fertilization, but even in the case operated after the gastrulation situs inversus cordis et viscerum and other anomalies have been observed. On the development of the fetus of the mouse, it is most effectual when the injection to the mother has been done at 8-10 days after the fertilization, resulting pseudencephaly, hydrocephaly, hydromyelia, microphthalmus, polydactyly, hemorrhage in the body wall and other anomalies.
On the other hand, we have also tested the effect of radioactive rainwater which has been brought about as a result of the explosion of atomic bombs since 1954. Dissolving the ashes of the rainwater into the distilled water, it has been injected into the pregnant mouse or used as a medium culturing the eggs of amphibia or Zebra Danio (a sort of tropical fish). The similar anomalies as induced by the radioisotopes are obtained in each case, that is, pseudencephaly, hydrocephaly etc. in the mouse fetus, microcephaly, anophthalmia, spin bifida, inversion of heart and visceral organs in Bufo vulgaris eggs, and cyclopia, vertebral flexure and other anomalies in Zebra Danio eggs. Remarkable is the fact that the effect of the radioactive rainwater is surprisingly serious, even when its radioactivity is considerably low.
