The Effects of Ozone Pollution

Each season's weather has its disadvantages. Summer days are hot with threats of sunburn or dehydration ... and ozone pollution. Data is increasingly emphasizing the ozone's adverse effects on health.

Some people are particularly sensitive to this type of pollution. However, it is still difficult to assess accurately the effects of ozone peaks.

When oxygen triples

Indeed, the development of this particular form of oxygen consisting of three oxygen atoms (when the oxygen in the atmosphere is usually composed of two) is closely linked to the action of ultraviolet rays on pollutants emitted by motor vehicles, particularly nitrogen dioxide (NO2).

Thus, its production is at its maximum at times when the sun is strongest; in the hot days when the sky is blue and the wind is low.

Under the effect of ultraviolet, nitrogen dioxide leaves an oxygen molecule to escape, which combines with oxygen in the atmosphere (O2) to form ozone (O3). The absence of wind and the warm layers of air elevate from the ground stagnating gas in the cities.

More frequent Asthma attacks

What are the consequences of this pollution? We know that ozone penetrates deep into the lungs and is irritating to mucous membranes of the nose, sinuses, bronchi and the conjunctiva. It can cause a sensation of irritation, coughing and breathing difficulties among those most vulnerable.

Various studies have also shown an increase in emergency admissions for asthma, and a resurgence of pneumonia at the peak of ozone pollution. The assessment of the effects of this gas remains difficult to assess accurately. Indeed, ozone is a harmful factor among others. Peak ozone levels are almost always associated with the presence of other pollutants for which the respective responsibility is difficult to estimate. Furthermore, the harmful effects of such pollution are modestly compared to other toxins such as tobacco, which many people are exposed to actively or passively.

Important fragile topics

The effects of ozone on lung functions are very sensitive. Thus, the respiratory capacities seem influenced by the concentration of ozone in the atmosphere, even when it is within the acceptable range. Laboratory tests indicate that the physical performance and lung capacity of athletes is dramatically reduced when the ozone amount increases.

Of course, the consequences are more severe for those people with reduced lung function, such as the elderly and those suffering from lung diseases such as chronic bronchitis, emphysema, asthma and respiratory insufficiency.

Long-term consequences?

Can repeated exposure to ozone peaks lead to serious consequences? Studies in rats are quite reassuring regarding the potential risk of lung cancer. In contrast, an American study suggests the possibility of chronic effects. Having examined the lung function of more than 500 non-smoking students from Yale, the authors concluded that young people who had lived for at least four years in an area exposed to pollution by ozone have a worse respiratory performance than others.

Finally it is important to remember that air pollution caused by ozone has nothing to do with the ozone layer that forms naturally in the stratosphere, well above the air we breathe. It has a protective effect by filtering aggressive sunlight for our skin.

Sources:

http://www.nytimes.com/1988/07/31/us/ozone-pollution-is-found-at-peak-in-summer-heat.html?sec=&spon=&pagewanted=all

http://www.eurekalert.org/pub_releases/2009-03/nlmc-sfl030609.php