An Investigation Study on PM2.5 in Ambient Air: A CaseStudy of Karachi, Pakistan

The susceptibility of ambient air quality is due to particle pollution from PM2.5, which is a great alarm when levels in the air are unhealthy. Inhalation in unhealthy levels of PM2.5 can raise the risk of health problems and also decrease visibility and cause the air to appear obscure. This research investigates the continuous accumulation of PM2.5 at hourly interval using an automated air monitoring instrument in 50 distinct locations' in the five districts of Karachi, Pakistan. Data were collected over a period, from January 1st until June 30th, 2022. During the research study duration, the PM2.5 concentration exhibited variability within the range of 2 to 374 μg/m3. The results revealed that the minimum and maximum PM2.5 concentrations in District South was 3 μg/m3 and 374 μg/m3 respectively followed by District Central (3 μg/m3 , 337 μg/m3), District West (3 μg/m3, 349 μg/m3), District East (2μ g/m3, 343 μg/m3) and District Malir (2 μg/m3, 199μg/m3) correspondingly. The entire sampling data 24-hours average was 114.88 μg/m3compared to the permissible limits of Sindh Environmental Quality Standards (SEQS-2016) 75 μg/m3 and World Health Organization (WHO) air quality guidelines 25 μg/m3 . The outcomes emphasize the necessity for implementing strict emission control protocols and promoting cleaner energy sources to mitigate the health risks associated with PM2.5 exposure. This research work underscores the urgency of air quality management strategies in Karachi, aiding policy makers and stakeholders in devising effective mitigation measures. Addressing the challenges posed by high-level PM2.5 can lead to significant improvements in the overall well-being and quality of life of the city's inhabitants