Karachi, Pakistan, is grappling with a significant air pollution crisis that poses serious respiratory health risks, particularly for vulnerable populations such as men, the elderly, and individuals with pre-existing lung conditions. A recent study by the Aga Khan University (AKU) highlights alarming trends in respiratory-related hospital visits correlating with rising pollution levels.
The study, published in Atmospheric Pollution Research, examined data from Karachi's major healthcare facilities, including the National Institute of Cardiovascular Diseases (NICVD), Jinnah Postgraduate Medical Centre (JPMC), and Aga Khan University Hospital (AKUH). It focused on fine particulate matter (PM2.5), a pollutant known for penetrating deep into the lungs and bloodstream, causing systemic health issues.
Researchers identified high concentrations of sulfate, ammonium, nitrate, and black carbon in the city's busiest areas, primarily attributed to industrial emissions, vehicular exhaust, and waste burning. Karachi's PM2.5 levels are among the highest globally, significantly exceeding the World Health Organization's (WHO) safety thresholds.
With a population of approximately 15 million, Karachi ranks as the third most polluted city in Pakistan, which is itself the third most polluted country worldwide. The city's dense traffic, industrial activity, and lack of green spaces exacerbate the air quality crisis.
Health experts warn that PM2.5 particles are linked to chronic bronchitis, respiratory infections, and cardiovascular diseases. A report from the American Heart Association indicates that these particles can elevate the risk of heart attacks and strokes due to their detrimental effects on blood vessels.
Emerging research suggests that long-term exposure to PM2.5 can impair lung function, particularly in children, and is associated with respiratory cancers. Additionally, studies indicate a potential link between air pollution and neurodegenerative diseases, as PM2.5 may cross the blood-brain barrier, leading to cognitive decline.
Public health officials are urging immediate action to address the air quality crisis in Karachi. They advocate for stricter emission regulations, the creation of green spaces, and enhanced public awareness campaigns regarding pollution's dangers. The WHO reports that a 10 g/m³ increase in PM2.5 levels corresponds with a 4% increased risk of mortality from all causes, underscoring the urgency of intervention in Karachi.