Ashby J, Purchase I F
ICI Central Toxicology Laboratory, Macclesfield, UK.
Environ Health Perspect. 1992 Nov;98:223-6. doi: 10.1289/ehp.9298223.
Perera recently discussed the very real problems that accompany any attempt to classify rodent carcinogens into two groups--genotoxic or nongenotoxic. Not the least of these problems is that no agreed definition of these two terms exist. Nonetheless, the current carcinogen databases, for example, that of the U.S. National Toxicology Program (NTP), clearly comprise two broad groups of carcinogens--DNA reactive, mutagenic and multiply carcinogenic chemicals, and others. The others appear to be nonreactive to DNA, are inactive in the primary mutagenicity assays, and usually elicit highly selective carcinogenic responses in animals. These two classes of carcinogen are illustrated by examples taken from the NTP database and are discussed within the possible context of the latter group not being active in humans or, if they are, only when a threshold dose has been exceeded, chronically.
佩雷拉最近讨论了将啮齿动物致癌物分为两类——遗传毒性或非遗传毒性——所伴随的实际问题。这些问题中最突出的一点是，这两个术语尚无公认的定义。尽管如此，目前的致癌物数据库，例如美国国家毒理学计划（NTP）的数据库，显然包含两大类致癌物——DNA反应性、诱变性和多重致癌性化学物质，以及其他物质。其他物质似乎对DNA无反应，在主要的诱变性试验中无活性，并且通常在动物中引发高度选择性的致癌反应。这两类致癌物通过取自NTP数据库的例子进行说明，并在后者可能在人类中无活性的背景下进行讨论，或者如果它们有活性，也仅在长期超过阈值剂量时才会有活性。
