Division of Occupational and Environmental Medicine, Laboratory Medicine, Lund University, Scheelevägen 2, 223 63, Lund, Sweden.
Unit of Metals & Health, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Environ Health. 2018 Mar 27;17(1):29. doi: 10.1186/s12940-018-0375-0.
Asphalt workers are exposed to polyaromatic hydrocarbons (PAHs) from hot mix asphalt via both inhalation and dermal absorption. The use of crumb rubber modified (CRM) asphalt may result in higher exposure to PAHs and more adverse effects. Our aim is to assess occupational exposure to PAHs from conventional and CRM asphalt paving by measuring PAH metabolites in urine, and to investigate the effects on mitochondrial DNA copy number (mtDNAcn) and telomere length.
We recruited 116 workers paving conventional asphalt, 51 workers paving CRM asphalt and 100 controls in Sweden, all males. A repeated-measures analysis included 31 workers paving both types of asphalt. Urine and blood samples were collected pre-working on Monday morning and post-working on Thursday afternoon after 4 days working. PAH metabolites: 1-hydroxypyrene (1-OH-PYR) and 2-hydroxyphenanthrene (2-OH-PH) were measured in urine by LC-MS/MS. Relative mtDNAcn and telomere length were measured by quantitative PCR.
Conventional and CRM asphalt workers showed higher 1-OH-PYR and 2-OH-PH than controls (p < 0.001 for all). Relative mtDNAcn were 0.21 units (p < 0.001) higher in conventional asphalt workers and 0.13 units (p = 0.010) higher in CRM asphalt workers compared to controls. Relative telomere length did not differ across occupational groups, but it was positively associated with increment of 2-OH-PH (β = 0.075, p = 0.037) in asphalt workers. The repeated-measures analysis showed no difference in either increment of 1-OH-PYP, or changes in effect biomarkers (mtDNAcn or telomere length) between paving with conventional and CRM asphalt. Increment of 2-OH-PH was smaller after paving with CRM asphalt.
Road asphalt paving in open areas resulted in PAHs exposure, as shown by elevation of PAH metabolites in urine. Asphalt workers may experience oxidative stress, evidenced by alternation in mtDNAcn; however the effects could not be fully explained by exposure to PAHs from the asphalt mixture.
热拌沥青中的多环芳烃（PAHs）可通过吸入和皮肤吸收途径进入到沥青工人体内。使用橡胶粉改性沥青（CRM）可能会导致更高的 PAHs 暴露和更多的不良影响。我们的目的是通过测量尿液中的 PAH 代谢物来评估传统和 CRM 沥青铺路作业中的职业性 PAHs 暴露，并研究其对线粒体 DNA 拷贝数（mtDNAcn）和端粒长度的影响。
我们在瑞典招募了 116 名从事传统沥青铺路工作的工人、51 名从事 CRM 沥青铺路工作的工人和 100 名对照工人，均为男性。一项重复测量分析包括 31 名从事两种类型沥青铺路的工人。在周一早上开始工作前和周四下午工作 4 天后收集尿液和血液样本。通过 LC-MS/MS 测量尿液中的 1-羟基芘（1-OH-PYR）和 2-羟基菲（2-OH-PH）。通过定量 PCR 测量相对 mtDNAcn 和端粒长度。
与对照组相比，传统和 CRM 沥青工人的 1-OH-PYR 和 2-OH-PH 均较高（均 < 0.001）。与对照组相比，传统沥青工人的 mtDNAcn 高 0.21 个单位（p < 0.001），CRM 沥青工人高 0.13 个单位（p = 0.010）。职业群体之间的相对端粒长度没有差异，但它与沥青工人 2-OH-PH 的增量呈正相关（β = 0.075，p = 0.037）。重复测量分析显示，在传统沥青和 CRM 沥青的铺装过程中，1-OH-PYP 的增量或效应生物标志物（mtDNAcn 或端粒长度）的变化均无差异。用 CRM 沥青铺装后，2-OH-PH 的增量较小。
在开放区域进行道路沥青铺设会导致 PAHs 暴露，这可以通过尿液中 PAH 代谢物的升高来证明。沥青工人可能会经历氧化应激，这表现为 mtDNAcn 的改变；然而，这些影响不能完全用沥青混合物中的 PAHs 暴露来解释。
