Comparison of Diesel and Biodiesel Emissions and Health Effects in Underground Mi

描述（由申请人提供）：评价和比较地下采矿中柴油和生物柴油排放物的暴露以及急性健康影响。背景资料：尽管矿井通风和排放控制，地下矿工暴露在柴油废气的浓度，经常超过160 μ g/m3的柴油颗粒物的MSHA标准。作为一种已知的致癌物质，柴油排放还与急性和慢性的呼吸和心血管健康影响有关。最近，作为减少颗粒物暴露的一种手段，已经推广使用生物柴油燃料作为柴油燃料的混合物。然而，没有研究评估与生物柴油混合物相比，柴油设备排放物对健康的影响，一些体外研究表明使用生物柴油的毒性更大。具体目标：1）评估与在地下矿井中使用柴油和生物柴油混合燃料设备相关的吸入暴露; 2）评估与暴露于使用柴油和生物柴油混合动力设备产生的排放物相关的健康影响和改变的生理学生物标志物;以及3）比较与暴露于柴油和生物柴油混合物排放物相关的健康影响和改变的生理学生物标志物的差异。研究设计：使用交叉实验设计交替使用柴油和50%生物柴油/柴油混合（B50）燃料，采矿和矿物工程专业的学生在地下矿山操作装载运输自卸车将被监测暴露于污染物和健康影响。将从矿井中采集可吸入粉尘、元素碳、黑碳、二氧化氮（NO2）、二氧化硫（SO2）、一氧化碳（CO）、醛类和多环芳烃（PAH）样本。将在暴露前和暴露后采集所有受试者的肺功能测定、症状、痰液、血液、尿液、呼出气和超声检查。将在诱导痰中分析炎症标志物和氧化应激标志物，包括白细胞介素（IL）-6、-8和-10、髓过氧化物酶（MPO）和基质金属蛋白酶-9（MMP-9）。将分析血液中的血管损伤介质，包括P-选择素和内皮素-1（ET-1）。将测定尿8-羟基-2 '-脱氧鸟苷（8-OHdG），以评估氧化性DNA损伤。将对呼出的一氧化氮（NO）（气道炎症的标志物）和呼出的一氧化碳（CO）（CO暴露的标志物）进行评价。将使用肱动脉血流介导的扩张超声来评价血管内皮功能的变化。将比较柴油和B50生物柴油暴露前后效应生物标志物的配对差异。对于每种燃料类型，将使用回归分析来模拟排放污染物对暴露前后个体生物标志物变化的影响。与公众健康的相关性：这项研究将有助于确定在地下采矿环境中使用生物柴油混合燃料的健康后果。关于在职业和环境环境背景下转换为生物柴油燃料的健康影响的信息也将有助于为未来的政策决定提供信息。 公共卫生相关性：地下采矿中柴油颗粒物的暴露量通常超过现有标准。目前正在使用生物农药混合物来减少这些接触，但没有资料说明这是否会增加、减少或不能改变设备排放物对矿工的毒性。这项研究将有助于确定在地下采矿环境中使用生物柴油混合燃料的健康后果。

DESCRIPTION (provided by applicant): To evaluate and compare exposure to diesel and biodiesel emissions and acute health effects in underground mining. Background: Despite mine ventilation and emission controls, underground miners are exposed to concentrations of diesel exhaust that frequently exceed the MSHA standard of 160 ¿g/m3 for diesel particulate matter. A known carcinogen, diesel emissions have also been linked to a broad range of respiratory and cardiovascular health effects, both acute and chronic. Recently, use of biodiesel fuel as a blend with diesel fuel has been promoted as a means of reducing particulate exposure. However, there have been no studies evaluating the health effects of exposure to emissions from equipment running on diesel fuel as compared with a biodiesel blend, and some in vitro studies suggest greater toxicity from biodiesel use. Specific aims: 1) Evaluate inhalation exposures associated with use of diesel and biodiesel blend-fueled equipment in an underground mine; 2) Evaluate health effects and biomarkers of altered physiology associated with exposure to emissions generated using diesel and biodiesel blend-powered equipment; and 3) Compare the differences in health effects and biomarkers of altered physiology associated with exposure to diesel and biodiesel blend emissions. Study design: Using a cross-over experimental design alternating use of diesel and 50% biodiesel/diesel blend (B50) fuels, mining and mineral engineering students operating a load-haul-dump vehicle in an underground mine will be monitored for exposure to contaminants and health effects. Respirable dust, elemental carbon, black carbon, nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), aldehydes, and polycyclic aromatic hydrocarbons (PAHs) will be sampled from the mine. Spirometry, symptoms, sputum, blood, urine, exhaled breath and ultrasonography will be collected on all subjects pre- and post-exposure. Inflammatory markers and markers of oxidative stress, including interleukin (IL)-6, -8 and -10, myeloperoxidase (MPO), and matrix metalloproteinase-9 (MMP-9) will be analyzed in induced sputum. Blood will be analyzed for mediators of vascular damage including P-selectin and endothelin-1 (ET-1). Urinary 8- hydroxy-2'-deoxyguanosine (8-OHdG) will be assayed to assess oxidative DNA damage. Exhaled nitric oxide (NO), a marker of airway inflammation, and exhaled carbon monoxide (CO), a marker of CO exposure will both be evaluated. Ultrasound of brachial flow-mediated dilation will be used to evaluate changes in vascular endothelium function. The paired differences in pre- and post-exposure biomarkers of effect will be compared for exposures to diesel and B50 biodiesel. For each fuel type, regression analysis will be used to model the effects of emissions contaminants on pre- to post-exposure changes in individual biomarkers. Relevance to public health: This study will help determine the health consequences of use of biodiesel fuel blends in the underground mining setting. Information on the health effects of conversion to biodiesel fuels in occupational and environmental settings will also help to inform future policy decisions. PUBLIC HEALTH RELEVANCE: Exposures to diesel particulate in underground mining often exceed existing standards. Biodiesel blends are being employed to reduce these exposures, yet there is no information on whether this increases, decreases or fails to change the toxicity to miners of equipment emissions. This study will help determine the health consequences of use of biodiesel fuel blends in the underground mining setting.