ABSTRACT

Thousands of abandoned uranium mines (AUMs) exist in the western United States. Due to improper remediation, windblown dusts generated from AUMs are of significant community concern. A mobile inhalation lab was sited near an AUM of high community concern (“Claim 28”) with three primary objectives: to (1) determine the composition of the regional ambient particulate matter (PM), (2) assess meteorological characteristics (wind speed and direction), and (3) assess immunological and physiological responses of mice after exposures to concentrated ambient PM (or CAPs). C57BL/6 and apolipoprotein E-null (ApoE^−/-) mice were exposed to CAPs in AirCARE1 located approximately 1 km to the SW of Claim 28, for 1 or 28 days for 4 hr/day at approximately 80 µg/m³ CAPs. Bronchoalveolar lavage fluid (BALF) analysis revealed a significant influx of neutrophils after a single-day exposure in C57BL/6 mice (average PM_2.5 concentration = 68 µg/m³). Lungs from mice exposed for 1 day exhibited modest increases in Tnfa and Tgfb mRNA levels in the CAPs exposure group compared to filtered air (FA). Lungs from mice exposed for 28 days exhibited reduced Tgfb (C57BL/6) and Tnfa (ApoE^−/-) mRNA levels. Wind direction was typically moving from SW to NE (away from the community) and, while detectable in all samples, uranium concentrations in the PM_2.5 fraction were not markedly different from published-reported values. Overall, exposure to CAPs in the region of the Blue GAP Tachee’s Claim-28 uranium mine demonstrated little evidence of overt pulmonary injury or inflammation or ambient air contamination attributed to uranium or vanadium.

摘要

美国西部存在数以千计的废弃铀矿 (AUM)。由于修复不当，AUM 产生的风尘引起了社区的重大关注。一个移动吸入实验室位于社区高度关注的 AUM（“索赔 28”）附近，其三个主要目标是：(1) 确定区域环境颗粒物 (PM) 的组成，(2) 评估气象特征（风速和方向），以及 (3) 评估小鼠暴露于高浓度 PM（或 CAP）后的免疫和生理反应。C57BL/6 和载脂蛋白 E-null (ApoE ^-/- ) 小鼠在距离权利要求 28 的西南约 1 公里的 AirCARE1 中暴露于 CAP，持续 1 或 28 天，持续 4 小时/天，浓度约为 80 µg/m ³CAP。支气管肺泡灌洗液 (BALF) 分析显示，在 C57BL/6 小鼠（平均 PM _2.5浓度 = 68 µg/m ³）中暴露一天后，中性粒细胞大量流入。与过滤空气 (FA) 相比，暴露 1 天的小鼠肺在 CAPs 暴露组中表现出 Tnfa 和 Tgfb mRNA 水平的适度增加。暴露于 28 天的小鼠的肺表现出降低的 Tgfb (C57BL/6) 和 Tnfa (ApoE ^-/- ) mRNA 水平。风向通常从 SW 移动到 NE（远离社区），虽然在所有样本中都可检测到，但 PM _2.5中的铀浓度分数与公布的报告值没有显着差异。总体而言，在 Blue GAP Tachee 的 Claim-28 铀矿区域暴露于 CAP，几乎没有证据表明明显的肺损伤或炎症或环境空气污染归因于铀或钒。