In the current study, electron paramagnetic resonance (EPR) spectroscopy was employed to measure environmentally persistent free radicals (EPFRs) in the total particulate matter (TPM) of mainstream and sidestream TPM of conventional cigarettes and the TPM of e-cigarettes. Comparable concentrations of EPFRs were detected in both sidestream (8.05 ± 1.32) × 104 pmol/g and mainstream TPM (7.41 ± 0.85) × 104 pmol/g of conventional cigarettes. TPM exposure to air resulted in long-lived oxygen centered, secondary radicals with EPR g values of 2.0041 for mainstream and 2.0044 for sidestream. Surprisingly, despite no combustion process, the TPM from e-cigarettes (menthol flavor of NJOY and V2 brands) also contain EPFRs with g values of 2.0031-2.0033, characteristic of carbon centered radicals, while the radical signal in the vanilla flavor of V2 brand was remarkably similar to semiquinones in cigarette smoke with a higher g value (2.0063). The radical concentration in e-cigarettes was much lower as compared to tobacco TPM. Although the production of ROS generated by e-cigarettes is comparatively lower than ROS generated by conventional cigarettes, EPFRs in e-cigarettes appear to be more potent than those in tobacco TPM with respect to hydroxyl radical generation yield per unit EPFR. EPFRs in e-cigarette TPM may be a potential source of health impacts.

中文翻译：

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从电子香烟和烟草香烟收集的总微粒物质中环境持久性自由基的比较研究。

在当前研究中，电子顺磁共振（EPR）光谱用于测量传统卷烟主流和侧流TPM的总颗粒物（TPM）以及电子烟的TPM中的环境持久性自由基（EPFR）。在传统卷烟的侧流（8.05±1.32）×104 pmol / g和主流TPM（7.41±0.85）×104 pmol / g中都检测到了可比的EPFRs。TPM暴露在空气中会导致长寿命的以氧气为中心的次级自由基，主流的EPR g值为2.0041，旁流的EPR g值为2.0044。令人惊讶的是，尽管没有燃烧过程，但电子烟的TPM（NJOY和V2品牌的薄荷味）也包含gFR为2.0031-2.0033的EPFR，这是碳中心自由基的特征，V2品牌的香草味中的自由基信号明显类似于香烟烟雾中的半醌，其g值较高（2.0063）。电子烟中的自由基浓度与烟草TPM相比要低得多。尽管电子烟产生的ROS的产量相对于常规香烟所产生的ROS相对较低，但就每单位EPFR的羟自由基产生产率而言，电子烟中的EPFR似乎比烟草TPM中的EPFR更有效。电子烟TPM中的EPFR可能是健康影响的潜在来源。尽管电子烟产生的ROS的产量相对于常规香烟所产生的ROS相对较低，但就每单位EPFR的羟自由基产生产率而言，电子烟中的EPFR似乎比烟草TPM中的EPFR更有效。电子烟TPM中的EPFR可能是健康影响的潜在来源。尽管电子烟产生的ROS的产量相对于常规香烟所产生的ROS相对较低，但就每单位EPFR的羟自由基产生产率而言，电子烟中的EPFR似乎比烟草TPM中的EPFR更有效。电子烟TPM中的EPFR可能是健康影响的潜在来源。