a Department of Environmental Health Sciences , College of Public Health, University of Georgia , Athens , GA , USA.
b Oak Ridge Institute for Science and Education , Oak Ridge , TN , USA.
Inhal Toxicol. 2019 Feb;31(2):73-87. doi: 10.1080/08958378.2019.1600079. Epub 2019 Apr 15.
Wildland firefighters conducting prescribed burns are exposed to a complex mixture of pollutants, requiring an integrated measure of exposure. We used urinary mutagenicity to assess if systemic exposure to mutagens is higher in firefighters after working at prescribed burns versus after non-burn work days. Other biomarkers of exposure and oxidative stress markers were also measured. Using a repeated measures study design, we collected urine before, immediately after, and the morning after a work shift on prescribed burn and non-burn work days from 12 healthy subjects, and analyzed for malondialdehyde (MDA), 8-isoprostane, 1-hydroxypyrene (OH-pyrene), and mutagenicity in YG1041 +S9. Particulate matter (PM) and carbon monoxide (CO) were measured by personal monitoring. Light-absorbing carbon (LAC) of PM was measured as a surrogate for black carbon exposure. Linear mixed-effect models were used to assess cross-work shift changes in urinary biomarkers. No significant differences occurred in creatinine-adjusted urinary mutagenicity across the work shift between burn days and non-burn days. Firefighters lighting fires had a non-significant, 1.6-fold increase in urinary mutagenicity for burn versus non-burn day exposures. Positive associations were found between cross-work shift changes in creatinine-adjusted urinary mutagenicity and MDA ( = 0.0010), OH-pyrene ( = 0.0001), and mass absorption efficiency which is the LAC/PM ratio ( = 0.2245), respectively. No significant effect of day type or work task on cross-work shift changes in MDA or 8-isoprostane was observed. Urinary mutagenicity may serve as a suitable measure of occupational smoke exposures among wildland firefighters, especially among those lighting fires for prescribed burns.
野外消防员在进行计划火烧时会接触到复杂的污染物混合物,因此需要综合评估暴露情况。我们使用尿液致突变性来评估在进行计划火烧工作后,与非火烧工作日相比,消防员的全身接触诱变剂的情况是否更高。还测量了其他暴露生物标志物和氧化应激标志物。使用重复测量研究设计,我们从 12 名健康受试者中收集了计划火烧和非火烧工作日工作班次前后的尿液,并分析了丙二醛 (MDA)、8-异前列腺素、1-羟基芘 (OH-芘) 和 YG1041+S9 的致突变性。通过个人监测测量了颗粒物 (PM) 和一氧化碳 (CO)。PM 的光吸收碳 (LAC) 作为黑碳暴露的替代物进行了测量。线性混合效应模型用于评估跨工作班次的尿液生物标志物的变化。在火烧日和非火烧日之间,工作班次中尿液致突变性与肌酐调整后无显著差异。点火的消防员在火烧日和非火烧日的尿液致突变性分别有非显著的 1.6 倍增加。在肌酐调整后的尿液致突变性与 MDA( = 0.0010)、OH-芘( = 0.0001)和质量吸收效率(即 LAC/PM 比, = 0.2245)的交叉工作班次变化之间发现了正相关。未观察到日型或工作任务对 MDA 或 8-异前列腺素的交叉工作班次变化有显著影响。尿液致突变性可能是野外消防员职业烟雾暴露的合适衡量标准,尤其是在点火进行计划火烧的消防员中。