Ozone impairs the body's immune system

According to a new study not only does air pollution exacerbate heart problems but it also impairs the body's immune system.

A study by researchers at Duke University Medical Center in Durham, N.C. has found that pollutants in ozone renders the body more susceptible to bacteria.

Even though scientists have known for some time of the damage pollution can inflict on the heart and lungs, the actual mechanisms involved were unclear.

The researchers at the university's pulmonary center, found that ozone exposure in mice at levels which equated to unhealthy levels for humans, enhanced lung injury in response to bacteria and cell death in immune system cells, which are used to fight off foreign toxins in the body.

For the study the mice breathed room air with levels of ozone that an active human would inhale on an unhealthy ozone-level day.

Dr. John Hollingsworth, a pulmonologist and lead author of the study says small amounts of inhaled foreign material can be relatively harmless, since they stimulate an appropriate innate immune response that protects the lungs.

Dr. Hollingsworth also says however that ozone appears to cause the innate immune system to overreact, killing key immune system cells, and possibly making the lungs more susceptible to subsequent invaders, such as bacteria.

Studies planned for the future will concentrate on how the pollutants interfere with system-wide immune system responses.

The study is published in the Journal of Immunology.