Smog-Related Health Problems

The term smog is generally used to mean chemical air pollution. The word is a combination of the words "smoke" and "fog." Smog primarily comes from the combustion of fossil fuels. A common example is car exhaust, which comes from the combustion of gasoline. There are many health problems that can occur due to smog exposure, most of which are nearly impossible to avoid in modern society.

The term smog is a general one - there are many different chemical particles that can cause air pollution. The severity of smog is generally assessed by measuring the ground level of ozone in an area. Ground-level ozone is different than the ozone layer, which is high up in the atmosphere. Smog levels in a particular area depend on many factors, including automobile use, manufacturing, weather conditions, and government regulations.

All persons are at risk of being affected by smog. The most commonly cited effect of smog is on the lungs and breathing. Senior citizens, children, and those with pre-existing lung conditions, such as asthma, are at the highest risk of smog-related breathing difficulty. Common symptoms from heavy smog exposure include shortness of breath, coughing, wheezing, and painful breathing. Watery eyes are another common symptom. These types of symptoms usually go away when a person can stop the exposure, such as remaining in-doors.

However, these symptoms can be quite serious in those with pre-existing health problems, such as those with asthma. For example, scientific studies have shown that the number of lung infections, hospital visits and hospitalizations goes up with increasing smog levels in those with asthma or other lung conditions. General lung function has also been shown to decline with increasing air pollution. Most concerning is the finding that an increased number of sudden deaths in those with prior heart or lung disease occurs in regions with high smog levels.

In addition, studies in well-trained athletes have shown a reduced capacity for exercise in areas with high levels of smog. There is also the concern that air pollution may lead to the development of new diseases, such as new cases of asthma or emphysema. A link between lung cancer and certain air pollutants is strongly suspected and likely, though more research is needed in this area.

The following measures are ways that individuals can help to reduce the air pollution:

Voting for politicians who support clean-air legislation;
Using public transportation, car pooling, cycling, or walking;
Buying a fuel-efficient, low-emission vehicle;
Keeping one's car well-tuned and having the emission control system checked regularly;
Supporting the development of alternatives to gasoline-powered engines;
Reducing home energy use.

High levels of smog occur more often on sunny, hot, and humid days. The peak smog levels are often during morning and afternoon rush-hour periods, when auto emissions are at their highest levels. It is a myth that smog is only found in large cities and industrial areas. Smog builds up in both urban and rural areas, as polluted air can spread out to cover large areas. The particles in polluted air give smog its well-known hazy appearance. Smog "episodes" can occur, when levels become higher than usual, and may last for days at a time.

When levels of smog are high, which is often mentioned in local news reports, those with heart or lung conditions need to be especially careful. Outdoor activity should be reduced, and exercise should only be done with great caution. Those who use inhalers should be sure to carry their medication at all times. Those at risk should know that high temperature and humidity can increase the negative health effects of smog.

The smog problem needs to be addressed on both a government and individual level. Measures to control manufacturing emissions and reduced auto emissions levels are examples of government regulations to reduce air pollution.

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