胚胎是一组处于高危状态的群体。早在二十年代人们就发现除病毒,细菌等生物因素外,多种理化因子可造成胚胎损伤。许多学者相继报道胚胎对致癌物作用敏感,并且出现了一些检测化学物质致畸和经胎盘后致癌的方法。但由于结构畸胎学检查难以查出一些弱致突变/致癌物的隐性细胞遗传学效应,而标准的经胎盘引癌试验周期长,耗费人力物力,使这些技术在实际应用上受到限制。据估计,目前人类应用的化学物质达20多万种,每年投入环 Embryos are a group of people at high risk. As early as the 1920s, people found that in addition to biological factors such as viruses and bacteria, a variety of physical and chemical factors can cause embryonic damage. Many scholars have reported that embryos are sensitive to carcinogens, and some methods to detect the teratogenicity of the chemical substances and carcinogenesis after placenta. However, due to the structural teratology test, it is difficult to detect the recessive cytogenetic effects of some weak mutagenesis / carcinogens. However, the long period of the standard transplacental carcinoid test consumes manpower and material resources, which limits the practical application of these technologies. It is estimated that currently more than 200,000 kinds of chemical substances are used by human beings, and the ring is put into use every year