Children in preschools were studied as an exceptionally vulnerable group to lung diseases due to their immature immune system. Few data are available in the literature addressing the exposure of children in preschools to ultrafine (>10 nm) particles. Exposure of children to fine, ultrafine (10 nm–1 µm) particles and black carbon particles present inside and near two preschools in Nur-Sultan, Kazakhstan, during Fall 2019 was investigated. For Preschool I, the average daily (6 h) indoor (outdoor) PM₁, PM_2.5, and PM₁₀ concentrations over three-week measurements were 15.0 (SD 12.5) µg/m³, 34.6 (SD 35.1) µg/m³, and 47.2 (SD 45.2) µg/m³, respectively. Average indoor UFP concentrations (>10.0 nm) including candle burning events were 5.20 × 10³ (SD 8.80 × 10³) particles/cm³, with the background UFP concentration to be 3.30 × 10³ (SD 1.80 × 10³) particles/cm³. In Preschool II, the average UFP concentration (>30.0 nm) in the morning and afternoon was 3.94 × 10³ (SD 5.34 × 10²) and 3.36 × 10³ (SD 1.90 × 10³) particles/cm³, respectively. Indoor black carbon (BC) concentrations were correlated with the outdoor smoking activity. The major sources of the indoor particles in the preschools were dust resuspension, candle burning, and infiltrated outdoor particles.

中文翻译：

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哈萨克斯坦努尔苏丹市两所幼儿园接触细小、超细颗粒和黑碳

由于免疫系统不成熟，学龄前儿童被视为特别容易患肺部疾病的群体。关于学龄前儿童暴露于超细 (>10 nm) 颗粒的文献中很少有数据可用。调查了 2019 年秋季儿童接触哈萨克斯坦努尔苏丹两所幼儿园内部和附近的细小、超细（10 纳米至 1 微米）颗粒和黑碳颗粒的情况。对于学龄前 I，在三周的测量中，平均每日（6 小时）室内（室外）PM ₁、PM _2.5和 PM ₁₀浓度分别为 15.0 (SD 12.5) µg/m ³、34.6 (SD 35.1) µg/m ³ , 和 47.2 (SD 45.2) µg/m ³， 分别。包括蜡烛燃烧事件在内的平均室内 UFP 浓度 (>10.0 nm) 为 5.20 × 10 ³ (SD 8.80 × 10 ³ ) 个粒子/cm ³，背景 UFP 浓度为 3.30 × 10 ³ (SD 1.80 × 10 ³ ) 个粒子/厘米³ . 在 Preschool II 中，上午和下午的平均 UFP 浓度 (>30.0 nm) 为 3.94 × 10 ³ (SD 5.34 × 10 ² ) 和 3.36 × 10 ³ (SD 1.90 × 10 ³ ) 个粒子/cm ³， 分别。室内黑碳 (BC) 浓度与室外吸烟活动相关。幼儿园室内颗粒物的主要来源是灰尘再悬浮、蜡烛燃烧和渗入的室外颗粒物。