What is air pollution?
Air pollution is a large number of gases, droplets and particles that reduce the quality of the air. Air can be polluted in both the city and the country. In the city, air pollution may be caused by cars, buses and airplanes, as well as industry and construction. Air pollution in the country may be caused by dust from tractors plowing fields, trucks and cars driving on dirt or gravel roads, rock quarries and smoke from wood and crop fires.
Ground-level ozone is the major part of air pollution in most cities. Ground-level ozone is created when engine and fuel gases already released into the air interact in the presence of sunlight. Ozone levels increase in cities when the air is still and the sun is bright and the temperature is warm. Ground-level ozone should not be confused with the "good" ozone that is miles up in the atmosphere and that protects us from radiation.
What symptoms does air pollution cause?
Air pollution can irritate the eyes, throat and lungs. Burning eyes, cough and chest tightness are common with exposure to high levels of air pollutants. However, responses to air pollution vary greatly in people. Some people may notice chest tightness or cough, while others may not notice any effects. Because exercise requires faster, deeper breathing, it may increase the symptoms. People with heart disease, such as angina, or with lung disease, such as asthma or emphysema, may be very sensitive to exposure to air pollution and may notice symptoms when others do not.
Is air pollution bad for health?
Fortunately for most healthy people, the symptoms of air pollution exposure go away as soon as the air quality improves. However, certain groups of people are more sensitive to the effects of air pollution than others. Children probably feel the effects of pollution at lower levels than adults. They also experience more illness, such as bronchitis and earaches, in areas of high pollution than in areas with cleaner air.
People with heart or lung disease also react more severely to polluted air. During times of heavy pollution, their condition may worsen to the point that they must limit their activities or even seek additional medical care. In the past, a number of deaths have been associated with severely polluted conditions.
Some of these gases can seriously and adversely affect the health of the population and should be given due attention by the concerned authority. The gases mentioned below are mainly outdoor air pollutants but some of them can and do occur indoor depending on the source and the circumstances.
Tobacco smoke: Tobacco smoke generates a wide range of harmful chemicals and is a major cause of ill health, as it is known to cause cancer, not only to the smoker but affecting passive smokers too. It is well-known that smoking affects the passive smoker (the person who is in the vicinity of a smoker and is not himself/herself a smoker) ranging from burning sensation in the eyes or nose, and throat irritation, to cancer, bronchitis, severe asthma, and a decrease in lung function.
Biological pollutants: These are mostly allergens that can cause asthma, hay fever, and other allergic diseases.
Volatile organic compounds: Volatile compounds can cause irritation of the eye, nose and throat. In severe cases there may be headaches, nausea, and loss of coordination. In the longer run, some of them are suspected to cause damage to the liver and other parts of the body.
Formaldehyde: Exposure causes irritation to the eyes, nose and may cause allergies in some people.
Lead: Prolonged exposure can cause damage to the nervous system, digestive problems, and in some cases cause cancer. It is especially hazardous to small children.
Radon: A radioactive gas that can accumulate inside the house, it originates from the rocks and soil under the house and its level is dominated by the outdoor air and also to some extent the other gases being emitted indoors. Exposure to this gas increases the risk of lung cancer.
Ozone: Exposure to this gas makes our eyes itch, burn, and water and it has also been associated with increase in respiratory disorders such as asthma. It lowers our resistance to colds and pneumonia.
Oxides of nitrogen: This gas can make children susceptible to respiratory diseases in the winters.
CO (carbon monoxide): It combines with hemoglobin to lessen the amount of oxygen that enters our blood through our lungs. The binding with other harem proteins causes changes in the function of the affected organs such as the brain and the cardiovascular system, and also the developing foots. It can impair our concentration, slow our reflexes, and make us confused and sleepy.
SO2 (sulfur dioxide): SO2 in the air is caused due to the rise in combustion of fossil fuels. It can oxidize and form sulfuric acid mist. SO2 in the air leads to diseases of the lung and other lung disorders such as wheezing and shortness of breath. Long-term effects are more difficult to ascertain as SO2 exposure is often combined with that of SPM.
SPM (suspended particulate matter): Suspended matter consists of dust, fumes, mist and smoke. The main chemical component of SPM that is of major concern is lead, others being nickel, arsenic, and those present in diesel exhaust. These particles when breathed in, lodge in our lung tissues and cause lung damage and respiratory problems. The importance of SPM as a major pollutant needs special emphasis as a) it affects more people globally than any other pollutant on a continuing basis; b) there is more monitoring data available on this than any other pollutant; and c) more epidemiological evidence has been collected on the exposure to this than to any other pollutant.
How to protect from air pollution?
People can protect themselves from the effects of air pollution by doing the following:
It is recommended to stay indoors as much during the day. Many pollutants have lower levels indoors than outdoors. One should limit outside activity to the early morning hours or wait until after sunset. This is important in high ozone conditions (as in many large cities) because sunshine drives up ozone levels. More pollution taken into the lungs in case of faster breath.
These steps will generally prevent symptoms in healthy adults and children. However, if people who live or work close to a known pollution source, or if you have a chronic heart or lung problem, talk with your doctor about other ways to deal with air pollution.