Air Pollution and Health

In a world that is becoming increasingly industrialized, there are cars, buses and airplanes, as well as industry and construction that cause air pollution. Every day we inhale in gallons of air, which is polluted with noxious gases and other particles. According to World Health Organization, air pollution is a major environmental risk to health and is estimated to cause approximately 2 million premature deaths worldwide per year.

What is Air Pollution?

Air pollution is a mixture of solid particles and gases in the air that causes the quality of the air to reduce drastically and become lethal to organisms breathing in it. These gases are nitrogen, oxygen, carbon dioxide, neon, argon, methane, helium, krypton, nitrous oxide, hydrogen, xenon and organic vapours. Particulate matter includes a wide range of pollutants like diesel soot, fly ash, wood smoke, nitrates in fertilizers, sulfate aerosols, lead, arsenic, metals, dust and allergens. Air pollution can have large negative effects on human health.

There are six major components of air pollution:

• Ozone at ground level: Ground-level ozone - not be confused with the "good" ozone layer in the upper atmosphere - is one of the major constituents of air pollution in most cities. It's made by a chemical reaction between pollutants such as nitrogen oxides and volatile organic compounds (VOCs) in the presence of heat and sunlight. Exhaust from vehicles, industrial emissions, gasoline vapors, and chemical solvents are major sources of nitrogen oxides and VOCs. The highest levels of ozone pollution occur during summer time. Excessive ozone in the air, especially during summertime, can be dangerous for people with respiratory illnesses. It can cause breathing problems, trigger asthma, reduce lung function and cause lung diseases.

• Particulates: Particulates, also referred to as particulate matter (PM) or fine particles, include dust, soot, dirt, smoke and liquid droplets suspended in the air. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires. Others are man made, originating as a result of human activities such as the burning of fossil fuels in vehicles, power plants and various industrial processes. Chronic exposure to particles contributes to the risk of developing cardiovascular and respiratory diseases, as well as of lung cancer. They can also cause decreased lung function, chronic bronchitis, difficulty in breathing, and irritation in eye, nose and throat.

• Carbon monoxide: Carbon monoxide is a colourless, odourless, non-irritating gas which is comes from vehicle exhaust, wood burning, forest fires, manufacturing processes and cigarettes. Carbon monoxide is a very poisonous gas which can reduce the body's ability to deliver oxygen to tissues and organs, such as the heart and brain. For people exposed to extremely high levels of this gas, it can be fatal. Carbon monoxide poisoning can lead to headache, loss of consciousness, difficulty performing complex tasks and even aggravation of heart problems like angina and coronary artery disease.

• Nitrogen oxides: Nitrogen oxides are a group of highly reactive gases. They, especially nitrogen dioxide, are emitted from burning of fuels by vehicles and industrial plants. They can often be seen as reddish brown layer over many urban areas. Long term exposure to nitrogen dioxide has been shown to increase symptoms of bronchitis in asthmatic children. Nitrogen oxides and sulfur dioxide react with other substances in the air to form acids which then fall to earth as rain, snow or fog.

• Sulfur dioxide: Sulfur dioxide is a colourless gas with a sharp odour. The main source of sulfur dioxide is the burning of sulfur-containing fossil fuels (petroleum and coal) for domestic heating, power generation and motor vehicles. Other sources include process of extracting gasoline from oil, or when metals are extracted from ore. Sulfur dioxide can affect the respiratory system and the functions of the lungs, and causes irritation of the eyes. Inflammation of the respiratory tract causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis. Further oxidation of sulfur dioxide in the presence of a catalyst such as nitrogen dioxide forms sulfuric acid. This is the main component of acid rain which is a cause of deforestation.

• Lead: The main sources of lead emissions are metals-processing facilities. Earlier leaded petrol used to be the main source of lead in the air, but it has been phased out. Lead can cause damage to liver, kidneys, brain and other organs. Excessive exposure can cause behavioral disorders, memory problems and seizures.

How is it damaging to the Health?

Air pollution is generally considered to be potentially deadly as it can:

• Affect Lungs: In a study of the effects of air pollution on children, researchers reported that children and teenagers in Southern California communities with higher levels of air pollution were more likely to have diminished lung function.

• Increase the risk of Diabetes: Researchers at Ohio State University Medical Center have found a strong connection between diabetes, diet, and air pollution. As part of the research, the research team exposed mice to the same dirty air that many of us breathe every day. The tests showed that air pollution increased body fat, caused inflammation and interferes with how the mice processed insulin, a hallmark of diabetes. The effects were strongest when combined with poor diet. Another study reported that the risk of death from diabetes can be more than two times higher in areas of high air pollution.

• Increase incidence of Bronchitis: Increased particulate exposure enhances the incidence of bronchitis in exposed population.

• Increase risk of lung cancer: According to a huge scientific study done on around half million people, long-term exposure to the air pollution can significantly increase the risk of lung cancer. The increase in risk is from combustion-related fine particulate matter - soot emitted by cars and trucks, coal-fired power plants and factories.

• Increase the risk of heart disease: American Heart Association (AHA) recently suggested that short- and long-term exposure to air pollution directly increases the likelihood of heart attack, stroke, or other cardiovascular problems. Fine particulate matter is again behind this increased risk factor.

• Respiratory diseases: Respiratory problems are a very natural and scientifically established result of air pollution. Problems like asthma, emphysema, pneumoconiosis are quite common in heavily polluted cities. A new study also links air pollution with the increased risk for breathing problems during sleep. More specifically, air pollution increased the risk of sleep-disordered breathing in which breathing stops briefly during sleep.

• Cause other problems: Higher levels of air pollution result in dizziness, mental confusion, severe headaches, nausea, and fainting on mild exertion.

What should I do?

Here are some tips to keep yourself safe:

• Stay indoors as much as you can during peak hours. If possible, limit outside activity to the early morning hours or evening hours as the sunshine in the afternoon can increase the ground ozone levels.
• If you have go out in peak hours, wear an air filter respirator.
• Don't exercise outdoors when air-quality is poor as due to faster breathing during exercise, you can take more pollution into your lungs.
• Stay away from smokers. Second hand smoke can speed up the development of atherosclerosis.
• Drive less, particularly on days with unhealthy air.
• Get some houseplants like rubber plant, palms (such as areca palm, reed palm and dwarf date palm) and ivy varieties (such as english ivy). They act like air filters improving your home's air quality.
• Eat lots of fruits and vegetables to get antioxidants such as beta carotene, vitamins C and vitamin E. They can help protect your lungs and heart from the ill effects of pollution-induced free radical damage.

If everybody were to take a vested interest in avoiding air pollution, this effort would go a long way!