Toronto study links air pollution to higher heart vessel blockage risk

Researchers at the University of Toronto have found that even moderate air pollution is associated with a measurable rise in coronary artery disease, based on data from 11,100 patients tracked at three major hospitals between 2012 and 2023. The team analyzed particulate matter and nitrogen dioxide levels in participants' residential areas alongside cardiac imaging results. Mid-range exposure was linked to a 13 percent increase in plaque buildup in the coronary arteries and a 23 percent rise in cardiovascular disease risk, according to the findings. Dr. Kate Hanneman, a radiologist on the research team, said the data showed heart disease rose noticeably even at pollution levels common in many developed countries. Concentrations of 7.5 micrograms of particulate matter per cubic meter and 12 parts per billion of nitrogen dioxide were tied to measurable vessel blockage. The study found that each one-microgram rise in particulate matter was associated with an 11 percent increase in calcium deposits on coronary vessel walls, a 13 percent rise in new cholesterol plaques and a 23 percent increase in vessel narrowing. Comparable increases in nitrogen dioxide were linked to a 4 percent higher risk of cardiac complications, with the effect more pronounced in men.