The effect of COVID-19 lockdowns on ambient air pollution levels in urban south-central Chile, where outdoor air pollution primarily originates indoors from wood burning for heating, may differ from trends in cities where transportation and industrial emission sources dominate. This quasi-experimental study compared hourly fine (PM_2.5) and coarse (PM₁₀) particulate matter measurements from six air monitors (three beta attenuation monitors; three low-cost sensors) in commercial and low/middle-income residential areas of Temuco, Chile between 2019 and 2020. The potential impact of varying annual meterological conditions on air quality was also assessed. During COVID-19 lockdown, average monthly ambient PM_2.5 concentrations in a commercial and middle-income residential neighborhood of Temuco were up to 50% higher (from 12 to 18 μg/m³) and 59% higher (from 22 to 35 μg/m³) than 2019 levels, respectively. Conversely, PM_2.5 levels decreased by up to 52% (from 43 to 21 μg/m³) in low-income areas. The fine fraction of PM₁₀ in April 2020 was 48% higher than in April 2017–2019 (from 50% to 74%) in a commercial area. These changes did not appear to result from meterological differences between years. During COVID-19 lockdown, higher outdoor PM_2.5 pollution from wood heating existed in more affluent areas of Temuco, while PM_2.5 concentrations declined among poorer households refraining from wood heating. To reduce air pollution and energy poverty in south-central Chile, affordability of clean heating fuels (e.g. electricity) should be a policy priority.

COVID-19 封锁对智利中南部城市环境空气污染水平的影响可能不同于交通和工业排放源占主导地位的城市的趋势，那里的室外空气污染主要来自室内燃烧木材取暖。这项准实验研究比较了 Temuco 商业区和中低收入住宅区的六个空气监测器（三个 β 衰减监测器；三个低成本传感器）的每小时细颗粒物 (PM _2.5 ) 和粗颗​​粒物 (PM ₁₀ ) 测量值， 2019 年至 2020 年间的智利。还评估了不同年度气象条件对空气质量的潜在影响。在 COVID-19 封锁期间，平均每月环境 PM _2.5Temuco 商业和中等收入居民区的浓度分别比 2019年高 50%（从 12 微克/米 3 到 18 微克/米³）和 59%（从 22 微克/米 3 到 35 微克/米^{3 ）。}相反，低收入地区的PM _2.5水平下降了 52%（从 43 微克/米 3 降至 21 微克/米^{3 ）。}商业区 2020 年 4 月PM _{10的细颗粒比 2017-2019 年 4 月高 48%（从 50% 到 74%）。}这些变化似乎不是由年份之间的气象差异引起的。在 COVID-19 封锁期间，Temuco 较富裕地区的木材加热造成的室外 PM _2.5污染较高，而 PM _2.5在不使用木材取暖的较贫困家庭中，浓度有所下降。为减少智利中南部的空气污染和能源贫困，清洁取暖燃料（如电力）的可负担性应成为政策重点。