Washington, May 6 (IANS) A mere 30 minutes of exposure to second hand smoke, wafting from another table in a bar, is enough to injure blood vessels even in healthy teetotallers. Compounding the damage, the exposure slows down the body’s repair mechanisms, which may have been activated by the injury, possibly for the next 24 hours, the study said.

Researchers concluded that results showed even brief exposure to passive smoke have strong and persistent consequences on the body’s vascular system, reports Sciencedaily.

Ten young adults participants were exposed to carefully controlled levels of secondhand smoke. It was equivalent to being in a bar where smoking is allowed. As a control, the same subjects were exposed to clean air on a different day.

In both settings, the researchers evaluated the subjects’ blood vessel health through ultrasound to measure blood flow and analysis of blood samples.

The study is the first of its kind to link injury to blood vessels with the decreased efficacy of the body’s own repair mechanism, namely the endothelial progenitor cells (EPCs). They are circulating stem cells playing a key role in the repair mechanism of injured blood vessels.

Even brief secondhand smoke exposure not only resulted in blood vessel injury, but it also interfered with the body’s ability to repair itself by making the EPCs dysfunctional, said Yerem Yeghiazarians of Translational Cardiac Stem Cell Programme, University of California.

These findings are appearing later Tuesday in the Journal of the American College of Cardiology.