Indoor air pollution associated with biomass combustion for cooking remains a significant environmental health challenge in rural regions of sub-Saharan Africa; however, routine monitoring of woodsmoke aerosol concentrations continues to remain sparse. There is a paucity of field data on concentrations of combustion-generated ultrafine particles, which efficiently deposit in the human respiratory system, in such environments. Field measurements of ultrafine and fine woodsmoke aerosol (diameter range: 10–2500 nm) with field-portable diffusion chargers were conducted across nine wood-burning kitchens in Nandi County, Kenya. High time-resolution measurements (1 Hz) revealed that indoor particle number (PN) and particle surface area (PSA) concentrations of ultrafine and fine woodsmoke aerosol are strongly temporally variant, reach exceedingly high levels (PN > 10⁶/cm³; PSA > 10⁴ μm²/cm³) that are seldom observed in non-biomass burning environments, are influenced by kitchen architectural features, and are moderately to poorly correlated with carbon monoxide concentrations. In five kitchens, PN concentrations remained above 10⁵/cm³ for more than half of the day due to frequent cooking episodes. Indoor/outdoor ratios of PN and PSA concentrations were greater than 10 in most kitchens and exceeded 100 in several kitchens. Notably, the use of metal chimneys significantly reduced indoor PN and PSA concentrations.

中文翻译：

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生物质燃烧厨房中超细和细木烟气溶胶数量和表面积浓度的高时间分辨率测量：肯尼亚西部的案例研究

与烹饪用生物质燃烧相关的室内空气污染仍然是撒哈拉以南非洲农村地区的一项重大环境健康挑战；然而，对木烟气溶胶浓度的常规监测仍然很少。在这样的环境中，关于燃烧产生的超细颗粒浓度的现场数据很少，这些颗粒会有效地沉积在人体呼吸系统中。在肯尼亚南迪县的九个燃木厨房中，使用现场便携式扩散充电器对超细和细木烟气溶胶（直径范围：10–2500 nm）进行了现场测量。高时间分辨率测量 (1 Hz) 显示超细和细木烟气溶胶的室内颗粒数 (PN) 和颗粒表面积 (PSA) 浓度随时间变化很大，⁶ /厘米³ ; PSA > 10 ⁴  μm ² /cm ³）在非生物质燃烧环境中很少观察到，受厨房建筑特征的影响，并且与一氧化碳浓度的相关性适中或较差。在五个厨房中，由于频繁的烹饪事件，PN 浓度在一天中的一半以上时间都保持在 10 ⁵ /cm ^3以上。在大多数厨房中，PN 和 PSA 浓度的室内/室外比率大于 10，在几个厨房中超过 100。值得注意的是，金属烟囱的使用显着降低了室内 PN 和 PSA 浓度。