Urban environment in South Asia: Study the ambient air quality in a midsize City in Bangladesh

Md. Monabbir Hossain ¹ Md. Tariqul Islam ^2* Sujit Sikder ³ Sarah L. Hemstock ⁴ Md. Aminul Islam ⁵ Mahmud Hossain Faruquee ⁵ Md. Zakir Hossain ⁶

• ¹ Bangladesh Agricultural University, Mymensingh, Dhaka, Bangladesh
• ² Cranfield University, Cranfield, United Kingdom
• ³ Leibniz Institute of Ecological Urban and Regional Development (LG), Dresden, Lower Saxony, Germany
• ⁴ The Themba Trust, United Kingdom, Lincoln, United Kingdom
• ⁵ Bangladesh University of Health Sciences, Dhaka, Dhaka, Bangladesh
• ⁶ Khulna University, Khulna, Khulna, Bangladesh

Urban environment is an urgent task in the fast-growing mid-size cities of South Asia. Ambient air pollution is triggered by unplanned urban landuse, lack of green and waterbodies, and therefore a rapid increase of the urban heat island (UHI) effect. This study focuses on pervasive ambient air pollution in the urban environment, primarily driven by particulate matter (PM), which presents a dire public health threat. An in-situ investigation on 48 sites in a mid-size but fast-growing city, Mymensingh, Bangladesh suggested that the PM2.5 concentration (118±64 µg/m 3 ) is about eight times higher than the daily average of WHO's guidelines (15 µg/m 3 ). Weekdays and weekends do not show significant differences in PM generation. Geospatial analysis suggests that good air quality conditions are not found in the study area, and >50% of people are exposed to PM10 in very unhealthy conditions (≥151 µg/m 3 ). Traffic, and commercial land cover generate the highest PM level. The monsoon climatic events control precipitation and are the most influential factor in diminishing PM concentrations. However, fast-growing mid-size cities like Mymensingh in Bangladesh and beyond in the South Asia is facing extreme ambient air pollution, that severely impact the public health. Therefore, more action-oriented research initiatives are needed to formulate and execute policies to control air pollution, considering local experiences, indigenous knowledge, logistics capabilities, cultural orientation, transparency, accountability, and strong collaboration, cooperation, and commitment among the publicprivate partnership.