Traditionally, direct-reading instruments have been used to directly determine the concentrations of indoor air pollutants that may exceed the regulation limits. However, these instruments cannot directly assess the potential health hazards of these pollutants to humans. In this study, we developed and improved a bacterial reverse mutation assay (Ames test) by using a direct gas exposure module to directly determine the mutagenicity of indoor air quality using five tester bacterial strains (TA98, TA100, TA102, TA1535, and TA1537). Thereafter, the module was used to evaluate the effects of exposure time, different concentrations of HCHO or toluene, and mutagenic activities. We found that TA100 was the most sensitive strain and was reverted by relatively lower concentrations of 0.035 ppm HCHO. Furthermore, 50 ppm of toluene exposures caused a significant increase in the number of revertant colonies of TA100 without S9 activation at the 1.5–8-h exposure time intervals. Our findings provide new evidence that gaseous HCHO exposure could display weak but direct, time-dependent, and dose-dependent mutagenic activities. The weak, direct-acting, indirect-acting, and time-dependent mutagen of 50 ppm toluene was also confirmed. Moreover, our improved Ames module and the exposure conditions provided in this study can be further applied to evaluate the mutagenicity of indoor air quality.

中文翻译：

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两种常见室内空气污染物甲醛和甲苯的致突变性评估

传统上，直读仪器用于直接测定可能超过规定限值的室内空气污染物浓度。然而，这些仪器不能直接评估这些污染物对人类的潜在健康危害。在本研究中，我们开发并改进了细菌回复突变试验（Ames 试验），通过使用直接气体暴露模块，使用五种测试细菌菌株（TA98、TA100、TA102、TA1535 和 TA1537）直接确定室内空气质量的致突变性。 . 此后，该模块用于评估暴露时间、不同浓度的 HCHO 或甲苯以及诱变活性的影响。我们发现 TA100 是最敏感的菌株，并被相对较低浓度的 0.035 ppm HCHO 逆转。此外，在 1.5-8 小时的暴露时间间隔内，50 ppm 的甲苯暴露导致 TA100 的回复菌落数量显着增加，而没有 S9 激活。我们的发现提供了新的证据，证明气态 HCHO 暴露可能表现出微弱但直接、时间依赖性和剂量依赖性的诱变活性。还证实了 50 ppm 甲苯的弱、直接作用、间接作用和时间依赖性诱变剂。此外，我们改进的 Ames 模块和本研究中提供的暴露条件可以进一步应用于评估室内空气质量的致突变性。还证实了 50 ppm 甲苯的弱、直接作用、间接作用和时间依赖性诱变剂。此外，我们改进的 Ames 模块和本研究中提供的暴露条件可以进一步应用于评估室内空气质量的致突变性。还证实了 50 ppm 甲苯的弱、直接作用、间接作用和时间依赖性诱变剂。此外，我们改进的 Ames 模块和本研究中提供的暴露条件可以进一步应用于评估室内空气质量的致突变性。