加拿大西部建筑中的可呼吸晶体二氧化暴露的决定因素
Melanie Gorman Ng1,2, Avril Mu Li2, Jérôme Lavoué3
1School of Population and Public Health, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
Annals of work exposures and health
|June 22, 2023
概括
在加拿大建筑工人中,可呼吸的晶体二氧化 (RCS) 暴露往往超过安全限值. 拆除和破碎任务,室内工作以及水泥等特定材料会导致更高的暴露率,这凸显了需要改进控制的必要性.
科学领域:
- 职业健康和安全问题 职业健康和安全问题
- 环境科学 环境科学
- 工业卫生 工业卫生
背景情况:
- 可呼吸的晶体二氧化 (RCS) 对建筑工人构成重大健康风险.
- 之前的监测表明,在各种建筑环境中可能存在过度暴露.
- 了解暴露决定因素对于有效的风险管理至关重要.
研究的目的:
- 在阿尔伯塔省,不列颠哥伦比亚省和曼尼托巴省的建筑工地量化基于任务的RCS暴露水平.
- 确定影响RCS暴露的关键因素,包括任务类型,工作环境和材料.
- 将暴露水平与已确定的职业暴露限值进行比较.
主要方法:
- 在2015年5月至2020年8月期间,从44家公司的70个工作场所收集了373个RCS空气样本.
- 使用多变量线性回归建模来分析暴露决定因素.
- 评估的省份,任务类型,工作环境,建筑材料,采样持续时间和工程控制作为预测因素.
主要成果:
- 总体几何平均 (GM) RCS 暴露量为0.045 mg/m3,超过了ACGIH 0.025 mg/m3的TLV.
- 拆除 (GM 0.30 mg/m3),破碎 (GM 0.16 mg/m3) 和研磨 (GM 0.081 mg/m3) 显示了最高的平均暴露.
- 户外工作 (暴露率降低39%),局部排气通风和湿与减少的暴露水平有关.
结论:
- 加拿大西部的建筑工人经常接触到超过推值的RCS.
- 任务类型,特别是拆除和破坏,显著影响暴露水平.
- 实施工程控制和优化工作实践对于减轻RCS风险至关重要.
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