Evidence growing of air pollution’s link to heart disease, death (USA)

The scientific evidence linking air pollution to heart attacks, strokes and cardiovascular death has "substantially strengthened," and people, particularly those at high cardiovascular risk, should limit their exposure, according to an updated American Heart Association scientific statement. The evidence is strongest for fine particulate matter (PM2.5) having a causal relationship to cardiovascular disease, said the expert panel of authors who updated the association's 2004 initial statement on air pollution, also published in Circulation: Journal of the American Heart Association. The major source of PM2.5 is fossil fuel combustion from industry, traffic, and power generation. Biomass burning, heating, cooking, indoor activities and forest fires may also be relevant sources, particularly in certain regions