Air quality in recreational spaces of Rajshahi City: a study of particulate matters and gaseous pollutants exceeding standard AQI levels
摘要
Public leisure areas and recreational environments serve as the primary environment for encouraging physical activity, psychological well-being, and social interaction. These places are often visited by people as they come here for recreational purposes and community events. Polluted air in recreational spaces poses significant health challenges. As a result, the ambient air quality (AAQ) in these areas is of major environmental and epidemiological concern. This study examines the spatial variability and short-term diurnal changes during peak hours of aerosols (PM2.5, PM10, PM1.0), gaseous substances (HCHO, TVOC), temperature, and humidity of 15 popular public leisure areas and recreational spaces in Rajshahi. Additionally, Pearson correlation, t-Test, Principal Component Analysis (PCA), Hierarchical cluster analysis (HCA), and Z-score analysis were conducted, and the calculated Air Quality Index (AQI) was compared with BNAAQS, US EPA NAAQS, and WHO standards. Individually measured AQI in these fifteen study sites varied from 13 to 177. That means, not all recreational spaces offer healthy air quality levels. From the spatiotemporal study, the highest concentrations of the single pollutants were detected in Padma Garden: PM2.5 (105 µg/m3), PM10 (135 µg/m3), and PM1.0 (70 µg/m3). Although significant correlations were observed among PM2.5, PM10, and PM1.0 (p < 0.01), gaseous pollutants (HCHO and TVOC) showed weak and non-significant correlations with particulate matter. The PM2.5 levels in 6 spaces are under the ‘Unhealthy’ category by BNAAQS and US EPA NAAQS, whereas it has exceeded the WHO standards in all fifteen spaces. Analysis showed that PM2.5, PM10, and PM1.0 levels of these spaces are strongly correlated with one another, and along with these three aerosols, temperature and humidity vary significantly with time, whilst the other parameters do not. Sustainable urban planning requires a well-designed and well-monitored recreational centre to ensure the well-being of its dwellers. In this regard, this study revealed the prevailing conditions and scope of improvement.