The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd., Coopers Plains, Brisbane, QLD 4108, Australia; CRC for Contamination Assessment and Remediation of the Environment, Mawson Lakes, Adelaide, SA 5095, Australia.
The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd., Coopers Plains, Brisbane, QLD 4108, Australia; CRC for Contamination Assessment and Remediation of the Environment, Mawson Lakes, Adelaide, SA 5095, Australia.
Chemosphere. 2015 Jun;128:321-6. doi: 10.1016/j.chemosphere.2015.01.058. Epub 2015 Mar 6.
Cytotoxicity of benzene, toluene, ethylbenzene and xylenes (BTEX) to human lung cells was explored using three different exposure methods: Method 1 - in normal 96-well plates using DMSO as a carrier vehicle, we exposed (a) human lung carcinoma A549 cells, (b) A549 cells over-expressed with cytochrome P450 2E1 cells, and (c) normal lung fibroblast LL-24 cells to benzene, toluene, ethylbenzene and xylene individually and in a mixture which models car exhaust gases for between 1-88 h. We found that the order of the BTEX potency is benzene<toluene<ethylbenzene=m-xylene with acute BTEX toxicity to A549≈LL-24>CYP2E1 over-expressed A549 cells. A significant difference was found between inter-assay responses for all 24h exposures (P<0.005) suggesting a poor assay repeatability. No sign of potency increase was found from 6 to 72 h exposures. Method 2 - Using sealed vials to expose A549 cells to benzene, toluene and ethylbenzene, we observed a twenty-fold increase in their cytotoxicity, but also with no time-course effect. Method 3 - Using air exposed hanging-drop cell culture, we were able to see both an increase of demonstration of toxicity and a time-course effect from 1 to 12h exposure. We conclude that exposing cells in sealed and unsealed media using DMSO as a carrier vehicle was not suitable for BTEX exposure studies. Hanging-drop air exposure has more potential. It should be noted that if there are any changes in their exposure matrixes, its exposure mass distribution in cells could differ.
采用三种不同暴露方法探索了苯、甲苯、乙苯和二甲苯（BTEX）对人肺细胞的细胞毒性：方法 1-在正常的 96 孔板中，使用 DMSO 作为载体，我们分别将（a）人肺腺癌 A549 细胞、（b）过表达细胞色素 P450 2E1 的 A549 细胞和（c）正常肺成纤维细胞 LL-24 细胞暴露于苯、甲苯、乙苯和二甲苯中，以及模拟汽车尾气的混合物中，暴露时间为 1-88 小时。我们发现 BTEX 的毒性顺序为苯<甲苯<乙苯=m-二甲苯，急性 BTEX 毒性对 A549≈LL-24>CYP2E1 过表达 A549 细胞。所有 24 小时暴露的试验间反应差异均有统计学意义（P<0.005），提示该检测方法的重复性较差。在 6 至 72 小时的暴露时间内，未发现效力增加的迹象。方法 2-采用密封小瓶使 A549 细胞暴露于苯、甲苯和乙苯中，观察到其细胞毒性增加了二十倍，但也没有时间过程的影响。方法 3-采用空气暴露的悬滴细胞培养，我们能够观察到毒性的增加和 1 至 12 小时暴露的时间过程效应。我们得出结论，用 DMSO 作为载体在密封和未密封的培养基中暴露细胞不适合 BTEX 暴露研究。悬滴空气暴露有更大的潜力。需要注意的是，如果它们的暴露基质发生任何变化，其在细胞中的暴露质量分布可能会有所不同。
