Air Pollution Connected To Heart Disease

A new study has reinforced the suspicion that air pollution is another major cause of heart problems. Pollutants from cigarette smoke and cooking oils can change breathing patterns, raise blood pressure and alter the heart rate after even short exposures, researchers discovered when they exposed 40 healthy volunteers to polluted air.

The effect was dramatic despite the fact that exposure levels were very low, reported the researchers from the University of Kentucky at the Annual Meeting of the American Physiological Society, held in New Orleans, in April 2009. Cigarette smoke, in particular, contains low levels of cadmium, a highly toxic metal, and the inorganic—and more toxic—form of arsenic. Even second-hand smoke increases the risk of high blood pressure among nonsmokers (Am J Epidemiol, 2005; 162: 1037–49).

The air itself also contains a mixture of chemicals, heavy metals, solvents, polycyclic hydrocarbons, pesticides and ozone. These come from carexhaust fumes, jet fuel, pesticides, industrial waste and power plants. All forms of air pollution have been linked to raised blood pressure, stroke, heart attack, blood clots and hardening of the arteries (Rev Environ Health, 2007; 22: 115–37).

Finally, the air we breathe contains particulate matter (PM) that is a mixture of particles and liquid droplets. It is a mix of acids, such as nitrates and sulphates, organic chemicals, metals, and soil and dust particles. These particles can affect the heart and lungs, and cause serious health problems (see www.epa.gov/air/ particlepollution/ for more details).

PM can also worsen the health status of those with existing heart problems and those who have increased markers of inflammation (Environ Health Perspect, 2006; 114: 992–8).