From Science News Letter, August 30, 1958

NO “SAFE” RADIATION DOSE — There is no period of safety after exposure to harmful radiation, a geneticist reports. Radiation has been found to affect the primitive germ cell from which the sperm develops. Chromosome abnormalities may be transmitted to offspring in dangerous numbers for a long time after irradiation of the male. This also is important evidence that there is no such thing as a “minimum permissible dose of radiation,” says Dr. A.B. Griffen of the Roscoe B. Jackson Memorial Laboratory, Bar Harbor, Me. Until now many scientists had believed the effects of irradiation on the male sex organs were not long-lasting.… A pilot study using mice indicates, however, that “for the mouse, and presumably for man, there is no period of safety after irradiation” and visible, detectable breaks in chromosomes or aberrations can be passed on to offspring.