Experimental evidence

Abstract

Animal experiments have been performed on transplancental carcinogenesis whereby various substances were administered at different times during the embryonal period with tumorigenic effects in the offspring. For example, 29 chemicals have been listed by Tomatis which induce tumors following prenatal exposure. Substances which work transplacentally in animals as carcinogens are also present in man's environment. Precursors of nitrosamines can be found in many foodstuffs as well as multiple pharmaceutica. During pregnancy every woman is possibly brought into contact with various amounts and numbers of such or similar substances which make up a part of industrial pollution and theoretically can already endanger her unborn child. It is interesting that in man the neoplasms of children are, in a high percent, those of the nervous system. From this might be alluded that the nervous tissue probably has an especially high sensitivity to carcinogenic substances during the prenatal development which might be attributed to a pronounced cellular proliferation during this period.