Tobacco Smoke
Tobacco Smoke
Tobacco smoke has long been recognized as a major cause of mortality and morbidity, responsible for an estimated 434,000 deaths per year in the United States. It is also a source of indoor air pollution due to the release of harmful chemicals, particles, and carcinogens. Exposure to tobacco smoke affects everybody. Children are more vulnerable than any other age group because they are still growing and developing.
Chemical Composition and Health Effects
Tobacco smoke from cigarettes, cigars, and pipes is composed of more than 4,000 different chemicals including carbon monoxide and formaldehyde. More than forty of these compounds are known to cause cancer in humans or animals, and many of them are strong irritants.
The U.S. Environmental Protection Agency (EPA) has concluded that exposure to tobacco smoke in the United States poses a serious and significant public health threat. New long-term studies estimate that about half of all regular cigarette smokers die of smoking-related diseases. However, controversy still surrounds the exact extent of such health effects.
Attempts have been made to study the effect of tobacco smoke on individuals exposed to other toxic chemicals. The risk of developing lung cancer among asbestos workers grows when they smoke an increasing number of cigarettes per day and their cumulative asbestos exposure increases. Cigarette-smoking asbestos workers tend to develop both restrictive lung disease (decreased lung capacities) and chronic obstructive lung disease, as compared to nonsmoking asbestos workers who have a tendency to develop only restrictive lung disease.
In recent years, there has been great concern that nonsmokers may also be at risk for some of the above health effects as a result of their exposure to the tobacco smoke (known as secondhand smoke) that occurs in various environments occupied by smokers.
The tobacco industry has denied the claim of such health hazards and has legally challenged the EPA over its secondhand smoke findings. In addition, some researchers argue that a number of the studies involve flawed data or the selective interpretation of findings. Many of these critics contend that the health risks involved with secondhand smoke are not as extensive as reported.
Regulations on Smoke-free Environment
As of December 31, 1999, smoke-free indoor air laws of one type or another had been enacted in forty-five states and the District of Columbia. Smoking in private work sites is limited in twenty states and the District of Columbia. Forty-one states and the District of Columbia have laws restricting smoking in state government work sites. Thirty-one states have enacted laws that regulate smoking in restaurants, and out of these, only Utah and Vermont completely prohibit smoking in restaurants.
Most European countries have regulations that either ban or restrict smoking to designated areas in public places such as government/private work sites, health care facilities, and educational facilities. Japan and Singapore also have enacted laws that restrict smoking to designated areas, whereas other Asian countries such as India have no regulations in place. South Africa introduced a ban on tobacco smoking in public places, including the workplace, in 1999.
see also Asbestos; Asthma; Cancer; Health, Human; Indoor Air Pollution.
Bibliography
american conference of governmental industrial hygienists. (1998). industrial ventilation: a manual of recommended practice, 23rd edition. cincinnati, oh: author.
wadden, richard a., and scheff, peter a. (1983). indoor air pollution: characterization, prediction and control. new york: wiley.
internet resources
american lung association. "trends in tobacco use." available from http://www.lungusa.org/data.
national cancer institute. "health effects associated with tobacco smoke." available from http://cis.nci.nih.gov/fact.
national tobacco information online system. "laws and regulations." available from http://apps.nccd.cdc.gov/nations.
Ashok Kumar and Sunil Ojha