Assessing the association between fine particulate matter (PM) constituents and cardiovascular diseases in a mega-city of Pakistan.
Environ Pollut. 2019 Jun 23 ;252(Pt B):1412-1422. Epub 2019 Jun 23. PMID: 31260941
Concerning PMconcentrations, rapid industrialization, along with increase in cardiovascular disease (CVD) were recorded in Pakistan, especially in urban areas. The degree to which air pollution contributes to the increase in the burden of CVD in Pakistan has not been assessed due to lack of data. This study aims to describe the characteristics of PMconstituents and investigate the impact of individual PMconstituent on cardiovascular morbidity in Karachi, a mega city in Pakistan. Daily levels of twenty-one constituents of PMwere analyzed using samples collected at two sites from fall 2008 to summer 2009 in Karachi. Hospital admission and emergency room visits due to CVD were collected from two large hospitals. Negative Binominal Regression was used to estimate associations between pollutants and the risk of CVD. All PMconstituents were assessed in single-pollutant models and selected constituents were assessed in multi-pollutant models adjusting for PMmass and gaseous pollutants. The most common CVD subtypes among our participants were ischemic heart disease, hypertension, heart failure, and cardiomyopathy. Extremely high levels of PMconstituents from fossil-fuels combustion and industrial emissions were observed, with notable peaks in winter. The most consistent associations were found between exposure to nickel (5-14% increase per interquartile range) and cardiovascular hospital admissions. Suggestive evidence was also observed for associations between cardiovascular hospital admissions and Al, Fe, Ti, and nitrate. Our findings suggested that PMgenerated from fossil-fuels combustion and road dust resuspension were associated with the increased risk of CVD in Pakistan.