煤焦油和沥青中的低分子量多环芳烃(PAH)具有致突变性,它对健康的潜在影响已引起人们日益关注。其中引起致突变性的主要成分看来是烷基化三环PAH。但在沙门氏菌/哺乳动物肝微粒体试验中,芴、菲、蒽是非致突变物,为此作者研究了甲基化对三环PAH致突变性影响。本文是评定甲基芴和甲基苯并芴对鼠伤寒沙门氏菌株TA 98和TA 100的致突变性。五种单甲基芴中,仅9-甲基芴在含有肝匀浆条件下对TA98和TA 100具有致变性,在缺乏代谢活化下,没有一种单甲基芴对TA100和TA 98有致突变性。具有致突变性的单甲基芴,必需在第9位上有甲基团,此情况也见于二甲基芴。在1,9-、2,3-和9,9-二甲基 Low molecular weight polycyclic aromatic hydrocarbons (PAHs) in coal tar and pitch are mutagenic and their potential health effects have drawn increasing attention. The main ingredient causing mutagenicity appears to be alkylated tricyclic PAH. But in the Salmonella / mammal liver microsome test, fluorene, phenanthrene and anthracene are non-mutagens. Therefore, the author studied the effect of methylation on the mutagenicity of tricyclic PAH. This article evaluates the mutagenicity of methylfluorene and methylbenzofluorene against the S. typhimurium strains TA 98 and TA 100. Of the five monomethyl fluorenes, only 9-methyl fluorene was mutagenic to TA98 and TA 100 in the presence of liver homogenate, and none of the monomethyl fluorenes mutagens TA100 and TA 98 in the absence of metabolic activation Sex. Monomethyl fluorenes that have mutagenicity must have a methyl group at the 9th position, as is also the case with dimethylfluorene. At 1,9-, 2,3- and 9,9-dimethyl