Secondhand smoke: even a little bit can do big damage

You’d think that because you are a nonsmoker, you are safe from the adverse effects of cigarettes. Actually it all depends on your environment.

It’s called secondhand smoking or passive smoking – and it happens when nonsmokers inhale cigarette smoke in the surroundings – in places such as restaurants, bars, and other public places where smoking is still allowed.

But what does actually happen during exposure to secondhand smoke? A study by researchers of the University of California in San Francisco looked into the effect of exposure to secondhand smoke. The study aimed to determine

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 [endothelial progenitor cells – EPCs] that comprise the body’s blood vessel repair mechanisms

Ten healthy adults aged 29 to 31 years old participated in the study. The participants were exposed to different environmental settings on 2 different days. One day they were exposed to an environment where passive smoking is simulated – the kind and amount of smoke one gets exposed to when staying inside an average bar for 30 minutes. On another day, the participants were exposed only to smoke-free air.

Blood vessel health and blood flow were measured before exposure, and 1 hour, 2-and-a-half hours, and 24 hours after exposure.

The results of the study showed that even a 30-minute exposure to secondhand smoke was enough to result in injury to blood vessels of young, healthy lifelong nonsmokers. In addition, passive smoking also adversely affects the body’s repair mechanisms by decreasing the efficacy of EPCs, circulating stem cells in the blood that play a key role in the repair mechanism of injured blood vessels.

Furthermore, these adverse effects lasted for 24 hours or even more – much longer than previously imagined.

I remember the days when there were still smoking sections on airplanes. Flying was an ordeal then. I can only imagine the health effects of secondhand smoking to flight attendants.

Until a few years ago, German trains still had smoking sections.

Many western countries have now banned smoking in restaurants, bars, airports, train stations, and other public places. Italy and France were among the first in the EU to become “smoke-free” and health authorities (source: European Society of Cardiology) have already reported a noticeable decrease in incidence of cardiovascular events in these countries, as follows:

15% decrease in admissions to emergency wards of patients with myocardial infarction and strokes in France

11.2% decline in acute coronary events reported in Rome

But there are many places in the developed world, including some states in the US and some countries in the EU where anti-smoking law is still being debated.

We have to move fast! Creating a smoke-free environment benefits the health of everybody – smokers and non-smokers alike.

Check out this newsbrief videoclip about passive smoking.

Sources:

UCSF News Office 2 May 2008

J Am Coll Cardiol, 2008; 51:1760-1771.