Environmental Tobacco Smoke: Also Known As Secondhand Smoke 

What ETS is
Sources of ETS
Health problems associated with ETS
Acute exposure to ETS
Chronic exposure to ETS
Decreasing exposure to ETS

What ETS Is

Environmental tobacco smoke (ETS) (also known as passive or second hand smoke) is the mixture of smoke that comes from the burning end of a cigarette, pipe, or cigar, and smoke exhaled by the smoker. It is a highly toxic form of indoor air pollution, whether one smokes or not. Environmental tobacco smoke is a complex mixture of over 4700 substances, including gases and particles, from incompletely burned tobacco.

Of these chemicals, there are 243 known substances that can cause cancer. Some of the substances in tobacco smoke include nicotine, formaldehyde, carbon monoxide, phenols, nitrogen oxides, naphthalenes, tar, nitrosamine, PAHs, vinyl chloride, metals (cadmium, arsenic, antimony and zinc have been found in the particulates of cigarette smoke at elevated levels¹), hydrogen cyanide, ammonia, radioactive polonium 210, and various volatile organic compounds (VOCs). One study found that indoor VOC air concentrations in homes with smokers averaged 1.2 ppb of benzene higher than homes without smokers. ² According to results of the 1998 National Health Interview Survey, 24.1% of American adults currently smoke.³ According to Centers for Disease Control and Prevention (CDC), 43 percent of children, 2 months to 11 years of age, and 37 percent of adults live in a home with at least one smoker.

Sources of ETS

ETS comes from cigarettes, pipes, and cigars. One of the main differences between cigars and cigarettes is that while a single cigar can be smoked for a very long time (up to an hour or more), cigarettes rarely last more than about 10 minutes. Therefore, because of their mass, much more carbon monoxide, PAHs, and particulates come off cigars.

Secondhand smoke is smoke that comes directly off the burning tobacco without being filtered. It contains twice as much tar and nicotine as smoke inhaled through cigarette filters. Enviornmental tobacco smoke is found wherever smoking is allowed, including hospitality venues such as restaurants, sport arenas, bowling alleys, casinos and pool (billiard) halls; residences with smoking; and public buildings. More popular in recent years are the special clubs where people go to smoke cigars. One study measured carbon monoxide levels at a cigar smoking event with 50 people present and found carbon monoxide levels equal to that seen on a congested freeway during rush hour traffic.⁴

Health Problems Associated With ETS

Tobacco smoking is responsible for 434,000 deaths each year in the United States. ETS is the third leading cause of preventable death in the United States today. The health problems caused by ETS affect more people than just smokers. For example, the US Environmental Protection Agency (EPA) estimates that ETS causes approximately 3,000 lung cancer deaths and 37,000 heart disease deaths each year in nonsmokers. Of the 3,000 lung cancer deaths, an estimated 800 of these are from exposure to secondhand smoke in the home and 2,200 are from exposure in work or social situations. Nearly 9 out of 10 nonsmoking Americans are exposed to ETS with exposure higher among children, African Americans, and males according to the Third National Health and Nutrition Examination Survey.

A 1996 study by the American Lung Association (ALA) found that children exposed to ETS at home were 70 percent more likely to have wheezing with colds, 60 percent more likely to go to emergency rooms for wheezing, and 40% more likely to have persistent wheezing, compared with children in homes without ETS. The CDC estimates that children exposed to tobacco smoke in their homes have 18 million more days of restricted activity, 10 million more days of bed confinement, and miss 7 million more school days annually than other children, primarily due to acute and chronic respiratory conditions. Children's exposure to ETS is responsible for:

• 7 percent of ear infections

• 11 percent of asthma cases

• 13 percent of physician visits for cough

• 16 percent of all lung infections in children under five⁵

Smoking accounts for 87 percent of all lung cancer deaths, 82 percent of all deaths from chronic obstructive pulmonary disease (such as emphysema and chronic bronchitis), and 21 percent of all coronary heart disease.

There are many factors that determine if one might get sick due to exposure to ETS. These include:

• The concentration and amount of ETS. For example, the number of respiratory infections that children get depends directly on the amount of smoke in the home. Children who live with two smoking parents have more respiratory infections than children who live with one smoking parent. The lowest rates of respiratory infections and asthma are found in children of parents who do not smoke at all.

• Particulate levels in homes without smokers or other strong particle sources are the same as, or lower than, those outdoors. However, residences with one or more smokers may have particle levels several times higher than outdoor levels.

• Personal characteristics such as age, gender, weight, general health status. For example, ETS is responsible for increased severity of asthma symptoms in 200,000 to 1 million asthmatic children. In addition, the babies of women who smoke while pregnant are three times more likely to die from Sudden Infant Death Syndrome (SIDS). These babies are also more likely to have a low birth weight and have weaker lungs than do babies born to nonsmokers.

• The longer the exposure, the more at risk one is. Short-term exposure to ETS can irritate the eyes, nose, and throat. Long-term exposure can cause respiratory problems, such as wheezing, bronchitis, pneumonia, and lung cancer.

Health problems caused by ETS can either be acute, which occur immediately or within a few days of exposure, or they can be chronic, which are long-term health effects that might not show up for many years.

Acute Exposure to ETS

Acute exposure to ETS can result in: 

• Eyes, nose and throat irritation
  

• Headache

• Dizziness

• Nausea

• Loss of appetite

• Lack of energy

• Increased possibility of bacterial meningitis⁶

• Respiratory irritation with wheezing and coughing, possibly leading to frequent upper respiratory infections (especially in children) more colds and sore throats

Chronic Exposure to ETS

Chronic exposure to ETS can result in:

• Chronic respiratory conditions, like emphysema and bronchitis.

• Increased risk for asthma from breathing in the smoke of 10 cigarettes a day raises a child's chances of getting asthma, and increases the severity of, or difficulty in controlling, asthma.

• Increased risk for earaches from fluid in the middle ear (in children). This is a sign of chronic middle ear disease and is the most common cause of hospitalization for surgery in children.

• Snoring.

• Sudden Infant Death Syndrome.

• Increased risk for repeated pneumonia or bronchitis in children: the EPA estimates that between 150,000 and 300,000 of these cases will occur every year in infants and young children up to 18 months of age because of ETS exposure. Of these, 7,500 to 15,000 are serious enough to require hospitalization.

• Slower growth rates (in children).

• Reduced lung function (first seen in older children).

• Heart disease .

• Lung cancer.

All of these diseases contribute to the annual costs of smoking (health costs and lost productivity), which exceed $100 billion in the United States alone.

Decreasing Exposure to ETS 

Environmental tobacco smoke can be totally removed from indoor air only by removing the source: cigarette, cigar and pipe smoking. A separate smoking area, mechanical ventilation, or air cleaners may reduce, but will not eliminate, nonsmokers' exposure to ETS.

Ventilation, a common method of reducing exposure to indoor air pollutants, will reduce but not eliminate exposure to ETS. Because smoking produces such large amounts of pollutants, natural or mechanical ventilation techniques do not remove them from the air as quickly as they build up. In addition, the large increases in ventilation it takes to significantly reduce exposure to environmental tobacco smoke can also increase energy costs substantially.

Steps to reduce exposure:

• If you smoke, quit!

• Do not smoke in your home or permit others to do so.

• Do not smoke if children are present, particularly infants and toddlers.

• If you live or work with a smoker, work together to make changes. Start by being positive and supportive. Let the smoker know that you care about him or her.

• Make sure that any outside group that assists in the care of children, such as schools and day care facilities, has a smoking policy in force that protects children from exposure to ETS.

• Look for a job at a smoke-free workplace. If your workplace does not have a smoking policy that protects nonsmokers from exposure to ETS, try to implement one. Consider a ban on smoking indoors. Once a policy is in effect, make sure it is followed. In one study 28 percent of the nonsmokers and 13 percent of smokers reported that policies regarding smoking were not being obeyed at their workplaces.⁷

• Let people know when their smoke is causing immediate problems. If it is making your allergies worse, making you cough or wheeze, or making your eyes sting, say so. Some smokers may put their cigarettes away when they see the discomfort it causes.

• Eat in a smoke-free environment and avoid areas where you know there is a chance for smoke to irritate your allergies or sensitivities. It is not enough to just sit in a nonsmoking area where smokers and nonsmokers are separated since nonsmokers will still be exposed to re-circulated smoke or smoke drifting into nonsmoking areas.

• Help children avoid the secondhand smoke of smokers who use tobacco around them. Have them leave the room or play outside while an adult is smoking. Air out all areas after smoking occurs. Keep smokers away from children's sleeping areas.

• Do not smoke in the car. The high concentration of smoke in a small, closed compartment substantially increases the exposure to other passengers.

• Use no-smoking signs, buttons, and stickers at home, at work, and in your car.

• If smoking indoors cannot be avoided, increase ventilation in the area where smoking takes place. This should be a separate room, away from populated areas with its own ventilation system capable of providing 60 cfm of supply air per smoker. However, there are many cancer-causing chemicals in tobacco smoke and there is no safe level of exposure to carcinogens.

• If the designated smoking area is outdoors, it should not be immediately outside the door where nonsmokers have to pass or near building ventilation air intakes.

• Use high efficiency air cleaning systems. Remember most air cleaners, including the popular desktop models, cannot remove the gaseous pollutants from ETS.

• Have smokers use smokeless ashtrays and extinguish cigarettes quickly and completely.

References

1. Landsberger S, Wu D. The impact of heavy metals from environmental tobacco smoke on indoor air quality as determined by Compton suppression neutron activation analysis. The Science of the Total Environment. 1995;173/174:323-337.

2. Akland GG. Exposure of the general population to gasoline. Environmental Health Perspectives. 1993 Dec;101 Suppl 6:27-32.

3. Cigarette Smoking Among Adults?United States, 1998, MMWR. 2000 Oct.;49 (39):881-4.

4. Klepeis NE, Ott WR, Repace JL. (1999). The effect of cigar smoking on indoor levels of carbon monoxide and particulates. Journal of Exposure analysis and Environmental Epidemiology. 1999;9(6):622-635.

5. O'Neill CG. "How and why; don't get stifled by musty, dusty air." The Washington Post. 2000 Jan.:Z22.

6. Fischer M, Hedberg K, Cardosi P, Plikaytis BD, Hoesly FC, Steingart KR, Bell TA, Fleming DW, Wenger JD, Perkins BA. Tobacco smoke as a risk factor for meningococcal disease. Pediatric Infect Dis J. 1997;16:979-83.

7. Heloma A, Kähkönen E, Kaleva S, Reijula K. Smoking and exposure to tobacco smoke at medium-sized and large-scale workplaces. American Journal of Industrial Medicine. 2000;37:214-220.