Mt. Sinai Irving J. Selikoff Center for Occupational and Environmental Medicine, New York, New York, USA.
J Occup Environ Hyg. 2012;9(5):298-307. doi: 10.1080/15459624.2012.672924.
This study identified activities and sources that contribute to ultrafine and other submicron particle exposure that could trigger respiratory symptoms in highway repair workers. Submicron particle monitoring was conducted for paving, milling, and pothole repair operations in a major metropolitan area where several highway repair workers were identified as symptomatic for respiratory illness following exposures at the 2001 World Trade Center disaster site. Exposure assessments were conducted for eight trades involved in road construction using a TSI P-Trak portable condensation particle counter. Direct readings near the workers' breathing zones and observations of activities and potential sources were logged on 7 days on 27 workers using four different models of pavers and two types of millers. Average worker exposure levels ranged from 2 to 3 times background during paving and from 1 to 4 times background during milling. During asphalt paving, average personal exposures to submicron particulates were 25,000-60,000, 28,000-70,000, and 23,000-37,000 particles/ cm(3) for paver operators, screed operators, and rakers, respectively. Average personal exposures during milling were 19,000-111,000, 28,000-81,000, and 19,000 particles/cm(3) for the large miller operators, miller screed operators, and raker, respectively. Personal peak exposures were measured up to 467,000 and 455,000 particles/cm(3) in paving and milling, respectively. Several sources of submicron particles were identified. These included the diesel and electric fired screed heaters; engine exhaust from diesel powered construction vehicles passing by or idling; raking, dumping, and paving of asphalt; exhaust from the hotbox heater; pavement dust or fumes from milling operations, especially when the large miller started and stopped; and secondhand cigarette smoke. To reduce the potential for health effects in workers, over 40 recommendations were made to control exposures, including improved maintenance of paver ventilation systems; diesel fume engineering controls; reduced idling; provision of cabs for the operators; and improved dust suppression systems on the milling machine.
本研究确定了导致高速公路养护工人出现呼吸道症状的超细颗粒和其他亚微米颗粒暴露的活动和来源。在一个主要的大都市区进行了亚微米颗粒监测，该地区的几名高速公路养护工人在 2001 年世界贸易中心灾难现场暴露后出现呼吸道疾病症状。使用 TSI P-Trak 便携式冷凝粒子计数器对参与道路施工的 8 个行业进行了暴露评估。在 27 名工人身上进行了 7 天的监测，使用了 4 种不同型号的摊铺机和 2 种类型的铣刨机，在工人的呼吸区附近进行直接读数，并记录活动和潜在来源的观察结果。在铺筑过程中，工人的平均暴露水平在 2 到 3 倍背景水平之间，在铣刨过程中，工人的平均暴露水平在 1 到 4 倍背景水平之间。在沥青铺设过程中，摊铺机操作人员、刮平器操作人员和耙子操作人员的个人亚微米颗粒暴露量分别为 25,000-60,000、28,000-70,000 和 23,000-37,000 个颗粒/cm(3)。在铣刨过程中，大型铣刨机操作人员、铣刨机刮平器操作人员和耙子操作人员的个人暴露量分别为 19,000-111,000、28,000-81,000 和 19,000 个颗粒/cm(3)。个人最高暴露量高达 467,000 和 455,000 个颗粒/cm(3)，分别在铺设和铣刨过程中。确定了几个亚微米颗粒源。其中包括柴油和电动加热的刮平器加热器；路过或怠速的柴油驱动建筑车辆的发动机废气；耙子、倾倒和铺设沥青；热箱加热器的废气；铣刨作业产生的路面灰尘或烟雾，尤其是当大型铣刨机启动和停止时；以及二手烟。为了降低工人健康影响的风险，提出了 40 多项建议来控制暴露，包括改进摊铺机通风系统的维护；柴油烟雾工程控制；减少怠速；为操作人员提供驾驶室；以及改进铣刨机的抑尘系统。
