High levels of indoor fine particulate matter during the cold season in Almaty prompt urgent public health action

• DOI: 10.1371/journal.pone.0285477
• Publication Date: 2023-05-04T17:55:25Z
• Authors: Denis Vinnikov; Venerando Rapisarda; Sergey Babanov; Ermanno Vitale; Leonid Strizhakov; Zhanna Romanova; Irina Mukatova
• Keywords: Geometric standard deviation; Indoor air

Almaty is the largest city of Kazakhstan with extreme air pollution, mostly in cold season, but little known whether staying indoors could lessen exposure. The aim was to quantitatively characterize indoor fine PM levels and verify contribution ambient pollution it a polluted like Almaty.We collected forty-six 24-hour 15-min average samples similar number paired (total 92 samples). Predictors both PM2.5 mass concentrations mg/m3, including concentration, precipitation, minimal daily temperature humidity, along indoor/outdoor (I/O) ratio were tested adjusted regression models at eight lags.Ambient highly variable ranged from 0.001 0.694 mg/m3 (geometric mean (GM) 0.090, geometric standard deviation (GSD) 2.285). Snowing strongest predictor lower (median 0.053 vs 0.135 (p<0.001)). Indoor 0.002 0.228 (GM 0.034, GSD 2.254). In models, outdoor concentration explained 0.58 all variability 75-min delay (R2 0.67 lag8 on snowing days). Median I/O 0.386 (IQR 0.264 0.532) lag0 0.442 0.339 0.584) lag8.During season when fossil fuel burnt for heating, population exposed very high even indoors. Urgent public health action needed.