Smoke gets in your eyes: the hazards of secondhand smoke.

SMOKE GEST IN YOUR EYES

Even though you don't smoke, just living or working with smokers may endanger your health. Scientific studies show that exposure to the smoke of others, known as passive or involuntary smoke, may increase your risk of lung, cervical and breast cancer. Passive smoking may also increase your risk of heart disease, emphysema, bronchitis and stroke.

The smoke that fills the air from a burning cigarette is composed of two types of smoke: the smoke inhaled and exhaled by the smoker - mainstream smoke - and the smoke that comes from the end of a burning cigarette, cigar or pipe between puffs - sidestream smoke. Unfortunately, most of the smoke that reaches the lungs of nonsmokers is sidestream smoke, the most hazardous type of smoke.

Sidestream smoke has a 2.5 greater concentration of carbon monoxide than mainstream smoke. Under long-term exposure to sidestream smoke, heart disease can develop or be aggravated as carbon monoxide narrows blood vessels and combines with hemoglobin to reduce the oxygen-carrying ability of the blood.

This effect of carbon monoxide is one reason cigarette smoking has long been a primary risk factor in coronary heart disease. (CHD). Recently research also has begun to show a relationship between involuntary smoking and CHD. In the last five years, several studies have reported an increase in heart disease for passive …