Prior studies document a high prevalence of respiratory symptoms among brick workers in Nepal, which may be partially caused by non-occupational exposure to fine particulate matter (PM_2.5) from cooking. In this study, we compared PM_2.5 levels and 24 h trends in brick workers’ homes that used wood or liquefied petroleum gas (LPG) cooking fuel. PM_2.5 filter-based and real-time nephelometer data were collected for approximately 24 h in homes and outdoors. PM_2.5 was significantly associated with fuel type and location (p < 0.0001). Pairwise comparisons found significant differences between gas, indoor (geometric mean (GM): 79.32 μg/m³), and wood, indoor (GM: 541.14 μg/m³; p = 0.0002), and between wood, indoor, and outdoor (GM: 48.38 μg/m³; p = 0.0006) but not between gas, indoor, and outdoor (p = 0.56). For wood fuel homes, exposure peaks coincided with mealtimes. For LPG fuel homes, indoor levels may be explained by infiltration of ambient air pollution. In both wood and LPG fuel homes, PM_2.5 levels exceeded the 24 h limit (25.0 µg/m³) proposed by the World Health Organization. Our findings suggest that increasing the adoption of LPG cookstoves and decreasing ambient air pollution in the Kathmandu valley will significantly lower daily PM_2.5 exposures of brick workers and their families.

中文翻译：

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尼泊尔砖厂工人家中液化石油气炉灶和燃木炉火对 PM2.5 趋势的比较。


先前的研究表明，尼泊尔砖瓦工人呼吸道症状的患病率很高，部分原因可能是由于烹饪过程中非职业性接触细颗粒物 (PM _2.5 ) 造成的。在这项研究中，我们比较了使用木材或液化石油气 (LPG) 烹饪燃料的砖瓦工人家里的 PM _2.5水平和 24 小时趋势。基于 PM _2.5过滤器的实时浊度计数据在家庭和室外收集了大约 24 小时。 PM _2.5与燃料类型和位置显着相关 ( p < 0.0001)。成对比较发现室内气体（几何平均值 (GM)：79.32 μg/m ³ ）和室内木材（GM：541.14 μg/m ³ ； p = 0.0002）之间以及室内木材和室外木材之间存在显着差异（ GM：48.38 μg/m ³ ； p = 0.0006），但不在气体、室内和室外之间（ p = 0.56）。对于使用木材燃料的家庭来说，接触高峰期与进餐时间一致。对于液化石油气燃料家庭，室内水平可能是由于环境空气污染的渗透造成的。在木材和液化石油气燃料房屋中，PM _2.5水平超过了世界卫生组织提出的 24 小时限值（25.0 µg/m ³ ）。我们的研究结果表明，在加德满都谷地增加液化石油气炉灶的采用并减少环境空气污染将显着降低砖厂工人及其家人每日 PM _2.5的暴露量。