Department of Cell, Molecular, and Developmental Biology, University of California Riverside, Riverside, California, USA.
Department of Toxicology, University of California Riverside, Riverside, California, USA.
BMJ Open Respir Res. 2020 Feb;7(1). doi: 10.1136/bmjresp-2019-000452.
To determine if urinary biomarkers of effect and potential harm are elevated in electronic cigarette users compared with non-smokers and if elevation correlates with increased concentrations of metals in urine.
This was a cross-sectional study of biomarkers of exposure, effect and potential harm in urine from non-smokers (n=20), electronic cigarette users (n=20) and cigarette smokers (n=13). Participant's screening and urine collection were performed at the Roswell Park Comprehensive Cancer Center, and biomarker analysis and metal analysis were performed at the University of California, Riverside.
Metallothionein was significantly elevated in the electronic cigarette group (3761±3932 pg/mg) compared with the non-smokers (1129±1294 pg/mg, p=0.05). 8-OHdG (8-hydroxy-2'-deoxyguanosine) was significantly elevated in electronic cigarette users (442.8±300.7 ng/mg) versus non-smokers (221.6±157.8 ng/mg, p=0.01). 8-Isoprostane showed a significant increase in electronic cigarette users (750.8±433 pg/mg) versus non-smokers (411.2±287.4 pg/mg, p=0.03). Linear regression analysis in the electronic cigarette group showed a significant correlation between cotinine and total metal concentration; total metal concentration and metallothionein; cotinine and oxidative DNA damage; and total metal concentration and oxidative DNA damage. Zinc was significantly elevated in the electronic cigarette users (584.5±826.6 µg/g) compared with non-smokers (413.6±233.7 µg/g, p=0.03). Linear regression analysis showed a significant correlation between urinary zinc concentration and 8-OHdG in the electronic cigarette users.
This study is the first to investigate biomarkers of potential harm and effect in electronic cigarette users and to show a linkage to metal exposure. The biomarker levels in electronic cigarette users were similar to (and not lower than) cigarette smokers. In electronic cigarette users, there was a link to elevated total metal exposure and oxidative DNA damage. Specifically, our results demonstrate that zinc concentration was correlated to oxidative DNA damage.
确定电子烟使用者尿液中的效应和潜在危害的生物标志物是否高于非吸烟者，以及这些标志物的升高是否与尿液中金属浓度的增加相关。
这是一项在罗切斯特大学帕克综合癌症中心进行的非吸烟者（n=20）、电子烟使用者（n=20）和吸烟者（n=13）尿液中暴露、效应和潜在危害生物标志物的横断面研究。生物标志物分析和金属分析在加州大学河滨分校进行。
与非吸烟者（1129±1294 pg/mg，p=0.05）相比，金属硫蛋白在电子烟组中显著升高（3761±3932 pg/mg）。与非吸烟者（221.6±157.8 ng/mg，p=0.01）相比，8-OHdG（8-羟基-2'-脱氧鸟苷）在电子烟使用者中显著升高。与非吸烟者（411.2±287.4 pg/mg）相比，电子烟使用者的 8-异前列腺素（750.8±433 pg/mg）显著增加（p=0.03）。在电子烟组中，线性回归分析显示，可替宁与总金属浓度呈显著正相关；总金属浓度与金属硫蛋白；可替宁与氧化 DNA 损伤；以及总金属浓度与氧化 DNA 损伤。与非吸烟者（413.6±233.7 μg/g）相比，电子烟使用者的锌含量显著升高（584.5±826.6 μg/g，p=0.03）。线性回归分析显示，电子烟使用者尿锌浓度与 8-OHdG 呈显著正相关。
本研究首次调查了电子烟使用者潜在危害和效应的生物标志物，并显示与金属暴露有关。电子烟使用者的生物标志物水平与（而非低于）吸烟者相似。在电子烟使用者中，总金属暴露和氧化 DNA 损伤之间存在联系。具体来说，我们的结果表明，锌浓度与氧化 DNA 损伤有关。
