Secondhand Smoke

Exposure Can Cause Cell

Damage In 30 Minutes

ScienceDaily (May 5, 2008) — Exposure to secondhand smoke even for a brief period is injurious to health, a new study by researchers at the University of California, San Francisco has found.

According to the study, a 30-minute exposure to the level of secondhand smoke that one might normally inhale in an average bar setting was enough to result in blood vessel injury in young and otherwise healthy lifelong nonsmokers. Compounding the injury to the blood vessels themselves, the exposure to smoke impedes the function of the body's natural repair mechanisms that are activated in the face of the blood vessels' injury, the researchers report. Many of these effects persisted 24 hours later.

Study findings are reported in the online edition of the "Journal of the American College of Cardiology," and will appear in the Journal's May 6 print issue.

The results showed that brief exposure to real-world levels of passive smoke have strong and persistent consequences on the body's vascular system, the researchers conclude.

For the study, subjects were exposed to carefully controlled levels of secondhand smoke in a research setting. The smoke was equivalent to being in a bar where smoking is allowed--as it still is for 51 percent of the US population and in other countries, such as Germany--for 30 minutes. 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. In the exposure environment, this was done before exposure to establish baseline measures, immediately after exposure, and then 1 hour, 2.5 hours, and 24 hours after exposure. The study involved 10 young adult subjects between the ages of 29 and 31.

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). EPCs are circulating stem cells in the blood that play a key role in the repair mechanism of injured blood vessels.

The researchers examined three effects of secondhand smoke exposure:

• the effect of smoke on the mechanical function of blood vessels
• whether they could detect particles in the blood that are known to be increased in the blood due to blood vessel injury
• whether there was any effect on the stem cells (EPCs) that comprise the body's blood vessel repair mechanisms

"We wanted to study whether even a brief 30 minutes of exposure to second hand smoke in otherwise healthy subjects would result in blood vessel injury and how the body's own repair mechanisms--the EPCs--would be affected by such an exposure," says Yerem Yeghiazarians, MD, director of the Translational Cardiac Stem Cell Program at UCSF.

The secondhand smoke's effect on all measures was profound, he says. "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. It is quite amazing that only 30 minutes of exposure could cause such demonstrable effects." The study also showed that the deleterious effects of the exposure remain in the body for at least 24 hours, much longer than previously thought.

Study results showed that smoke exposure made EPCs less functional. "So it's a double hit: not only does a person develop blood vessel injury, but the cells that are supposed to help repair this damage are themselves also dysfunctional, compounding the injury," he says.

The public health implications of the study findings are significant, according to Yeghiazarians. "Our study helps explain why there is about a 20 percent drop in hospital admissions for heart attacks when cities and states pass laws mandating smokefree workplaces, restaurants and bars."

The study suggests that there is no safe level of exposure to secondhand smoke, he says.

The study was supported by awards from the Flight Attendant Medical Research Institute, the American Heart Association, the Wayne and Gladys Valley Foundation, and the UCSF Cardiac Stem Cell Foundation. In addition to Yeghiazarians, other lead investigators on the study are Christian Heiss, MD, and Nicolas Amabile, MD, who contributed to the work as fellows in the Division of Cardiology, Department of Medicine, at UCSF.

Other investigators in the study are Andrew C. Lee, MD; Wendy May Real, BS; Suzaynn F. Schick, PhD; David Lao, MD; Maelene L. Wong, BS; Sarah Jahn, MB; Franca S. Angeli, MD; Petros Minasi, BA; Matthew L. Springer, PhD; Stanton Glantz, PhD, FACC; William Grossman, MD, FACC; and John Balmes, MD, FACC; all of the Department of Medicine at UCSF. S. Katharine Hammond, PhD, of the Division of Environmental Health Sciences, School of Public Health, UC Berkeley, also contributed to the study.

Reducing Risk

Q:  What one easy step can a community take to instantly improve its health and economic well-being?

A: Go 100% smokefree indoors of course!

  Advocates and policymakers are curious to gauge and prove to nay-sayers how smokefee laws benefit a community. Science demonstrates that brief exposure(30minutes) to secondhand smoke can cause an individual to go into cardiac arrest, whether they actively smoke or not.  Because of secondhand smoke's unique and immediate effects on the heart, scientists can determine how much a smokefree law improves heart health.

  A number of communities, states, and nations are quantifying heart health improvements just one year after the smoke clears.  The results are clear:  Smokefree Laws reduce heart attacks, which results in increased health cost savings.  Let the facts speak for themselves!

• Helena, MT: 40% decrease in heart attacks (2004)
• Bowling Green, OH: 39% decrease in heart attacks after one year and 47% decrease in heart attacks three years after the smokefree law went into effect (2007)
• Pueblo, CO: 27% decrease in heart attacks (2006)
• NY: 8% decrease in heart attacks (3,813 people), $56 million increase in direct health cost savings (2007)
• Scotland: 17% decrease in heat attacks (2007)
• Ireland: 14% decrease in heart attacks (32,000 people) (2007)

  Remember, the U.S. Centers for Disease Control and Prevention warns: If you are at risk of heart disease (e.g., there is a history of heat disease in your family), avoid exposure to secondhand smoke due to its immediate effect on the heart.

Volume 26, Number 4     Winter 2007    Newsletter

Americans for Nonsmokers' Rights American Nonsmokers' Rights Foundation ©2008

The 2006 Surgeon General's Report on The Health
Consequences of Involuntary Exposure to Tobacco Smoke
confirmed the known health effects of secondhand smoke
exposure, including immediate adverse effects on the
cardiovascular system, and coronary heart disease and lung
cancer. The report concluded that there is no safe level of
exposure to secondhand smoke and that establishing smoke-free
environments is the only proven way to prevent exposure. The
report also finds that many millions of Americans are still exposed
to secondhand smoke despite substantial progress in tobacco
control. Here is the great video shown at the Surgeon General
press conference in June 2006.

As the body of scientific evidence becomes larger and more
precise, it is now possible to prove that smoke-free policies not
only work to protect nonsmokers from the death and disease
caused by exposure to secondhand smoke, but also have an
immediate effect on the public's health . On a larger scale, a
study has confirmed that restaurants and bars located in smoke-
free cities have 82% less indoor air pollution than restaurants
and bars in cities that do not have smoke-free protection. Because
of the mountain of evidence from these peer-reviewed, scientific
studies, the Centers for Disease Control recently issued a
warning for anyone at risk for heart disease to avoid smoke-filled
indoor environments completely.

Secondhand smoke kills. Knowing the science behind it, as
well as how smoke-free policies protect the public from
secondhand smoke will help cement this in the minds of the
public.

(Article taken from AMERICANS for NONSMOKERS’ RIGHTS
web-page (www.no-smoke.org) Getting the Facts – Secondhand
Smoke on 08-29-07)