Barnes W S, Klekowski E J
Environ Health Perspect. 1978 Dec;27:61-7. doi: 10.1289/ehp.782761.
Mutagens dispersed in ecosystems are usually in low concentration and episodic in occurrence. The possibility of detecting such dispersed mutagens by utilizing indigenous bioconcentrator organisms coupled with a microbial mutagen assay offer a useful screening protocol. There are numerous examples of plant and animal species which concentrate toxic substances from the environment. Body extracts of these bioconcentrators can be suitably fractioned and tested for mutagens with various microbial mutagen assays. The fractions may be tested with a broad range of microbial assays covering numerous genetic end points as well as both with and without mammalian microsomal activation. This kind of environmental screening has an advantage over physicochemical techniques, in that sampling techniques are simpler and a wider chemical spectrum can be screened. There are problems inherent with testing a complex biological extract, however. If a reversion assay is used, the metabolite necessary for growth may be present. Toxins may be introduced, either concentrated from the environment in the same way as the mutagen, or produced by the concentrator itself. Finally, the concentrator may also produce an endogenous mutagen which will give spuriously active extracts. Methods for minimizing some of these difficulties are discussed.
分散在生态系统中的诱变剂通常浓度较低且偶发出现。利用本地生物富集生物结合微生物诱变检测来检测此类分散诱变剂的可能性提供了一种有用的筛选方案。有许多动植物物种会从环境中富集有毒物质的例子。这些生物富集器的身体提取物可以进行适当分级，并通过各种微生物诱变检测来检测诱变剂。这些分级部分可以用涵盖众多遗传终点的广泛微生物检测方法进行检测，并且可以在有和没有哺乳动物微粒体激活的情况下进行检测。这种环境筛选相对于物理化学技术具有优势，因为采样技术更简单，并且可以筛选更广泛的化学物质谱。然而，检测复杂的生物提取物存在一些固有问题。如果使用回复突变检测，生长所需的代谢物可能存在。毒素可能会被引入，要么与诱变剂以相同方式从环境中浓缩而来，要么由富集器自身产生。最后，富集器也可能产生内源性诱变剂，这会导致提取物出现假阳性活性。本文讨论了将其中一些困难降至最低的方法。
