Big risks from a little ozone

Just two hours. That’s all it takes for air pollution to damage your heart.

It’s a disturbing finding, published in the July issue of the journal Circulation. And researchers point to ozone as the primary offender. Ozone is created when pollutants from car engines, industrial plants, and other sources react to the sun’s rays.

Ozone levels are particularly bad during summertime. And this study shows it takes very little ozone to affect your heart.

Researchers recruited 23 healthy young volunteers for the study. The participants were randomly exposed to two hours of clean air and two hours of high-ozone air while exercising off and on.

During the ozone exposure, their blood showed big increases in several markers for inflammation:

  • 98.9 percent increase in interleukin-8, which is a predictor of heart failure
  • 21.4 percent decrease in plasminogen activator inhibitor-1, which helps dissolve blood clots
  • 51.3 percent decrease in high-frequency heart rate, which means heart rhythm was affected

Changes in lung function were also evident.

While these were temporary changes in the young volunteers, they can be extremely dangerous for older people. Other studies have linked ozone exposure to heart attacks and sudden death.

Even though I encourage you to get outside for that after-dinner walk, use caution during summer months. There are plenty of ways to get the exercise you need indoors on those hot, sunny days when the air is full of ozone.

“Controlled exposure of healthy young volunteers to ozone causes cardiovascular effects.” Circulation 2012; 126(1): 104-111.