Karachi is the largest city in Pakistan and the 12th largest city in the world is facing a significant air pollution problem.[1] The air quality of Karachi has been deteriorating over the years, with pollution levels often exceeding safe limits set by the World Health Organization (WHO).[2]
Karachi's air quality index (AQI) has risen to an unhealthy level of 193, making it the fourth most polluted city in the world.[2] The city's AQI is often among the highest globally, indicating severe levels of air pollution.[3]
Fine particulate matter (PM2.5) plays a major role in air pollution in Karachi. The concentration of PM2.5 in the city has been recorded as 11.8 times higher than WHO's annual air quality guideline value.[2] The 24-hour average PM2.5 in Korangi was 101 ± 45.6 μg/m3 and 76.5 ± 38.4 μg/m3 in Tibet Center. These levels are significantly higher during winter, suggesting increased combustion activity and reduced wind dispersion.[4]
Major sources of air pollution in Karachi include transport and industrial emissions, waste burning, generators, emissions from refrigerators, dust blowing and stoves used in homes and hotels.[2] 70% of the air pollution in Karachi is emitted by motor vehicles.[5]
Karachi's environment has been badly affected by air pollution. All types of forests along Sindh's coastline, including mangroves, which used to help absorb carbon dioxide and clean air in Karachi, have dwindled to alarming levels. Over the past 50 years, Karachi has lost 10,000 hectares of mangrove forests to encroachment, commercialization and infrastructure development.[6]
Despite the alarming situation, the claims of the federal and government of Sindhs to invest heavily in the city to improve the environment and public health are nothing but lies and misinformation.[7][8] In light of deteriorating air quality, Sindh Caretaker Chief Minister Justice (Rtd) Maqbool Baqar has appealed to the public to ensure the use of face masks.[9]