Air pollution has a wide range of impacts on human health, some minor and some life-threatening. Different air pollutants raise different health risks. Some pollutants can cause health problems by themselves, while others are more likely to aggravate health conditions like asthma. Children, pregnant women, and the general adult population can all be affected in different ways. Chronic exposure to air pollution is more of an issue for people who have weakened immune systems, such as the elderly, people on chemotherapy, and people with AIDS.
Pregnant women, children, and people with compromised immune systems tend to be more vulnerable to air pollution. The effects of air pollution vary with the type of pollutant, with the duration of exposure, and a variety of personal variables.
Main Sources of Air Pollution:
Air pollution comes from a variety of indoor and outdoor sources. Indoor air, aka “sick building syndrome” - Chemicals that leach out of carpets and paints. The HVAC system might introduce mold and dust into the building. Air pollution might also leak into the building from the streets.
Emissions from motor vehicles: Anyone in a city is regularly exposed to the exhaust fumes from cars, commercial trucks, and buses. Those emissions tend to linger in the atmosphere and produce smog. The exhaust gases are hazardous even to people who aren’t out on the sidewalks and bike lanes.
Emissions from power plants: Burning coal and natural gas for power make for reasonable electric bills.However, the emissions contribute to smog and other forms of air pollution.
Factories: Lead, carbon monoxide, soot, and other compounds can find their way into the air from a wide range of industrial processes. Companies that manufacture lead-acid batteries or a wide range of plastics or industrial chemicals are especially prone to causing air pollution.
Forest Fires: The smoke from a fire, even one that does not threaten the area can cause air quality to plummet for a time.
Other Natural Phenomena: Natural phenomena can also exacerbate air pollution problems. A temperature inversion can trap pollutants near the ground. These temperature inversions have contributed to some of the famous smog events in cities like Los Angeles, Beijing, and Mexico City. Dust storms are a less-common issue in the United States than in parts of South Asia and Africa but still cause air quality problems.
Pollution need not originate in the country either. Smoke from fires in Southeast Asia has drifted to the United States. Air pollution has also made it to the United States from China.
Risks to Pregnancy:
Exposure to particulate pollution may increase the risk of low birth weight. Specifically, exposure to PM2.5 (particulates under 2.5 micrometers in diameter) at low levels has been shown to increase the risk of low birth weight by 18%. A study of 809 women in the San Joaquin Valley of California found that a range of birth defects their babies suffered where linked to smog or one of the components of it.
Risks to Children:
The National Institutes of Health have identified several health risks that are higher for children than for healthy adults. Children may experience more asthma attacks, more death and illness due to respiratory illnesses and decreased lung function. Those problems are mostly the result of outdoor air pollution.
Children are more active in general, tend to spend more times outdoors than adults, and are still developing. Those three facts make chronic exposure to air pollution more of a threat to them. Asthma symptoms are more likely to develop. Asthma attacks are more likely, especially when children live in smoggy environments.
Smog and Microparticles:
Smog is one of the most common forms of air pollution, at least in urban areas. That product of smoke, nitrogen oxides, sulfur oxide compounds, dust, water vapor, and/or ozone has produced some of the most famous air pollution in history. There were the famous smoggy days in Los Angeles and the great London smog event of 1953 that killed thousands of people. Large cities in eastern China develop terrible smog at times.
Smog causes breathing problems in the short term. It also irritates the eyes, nose, and throat. Chronic exposure or repeated exposure to dense smog can increase the risk of Alzheimer’s disease. The American Cancer Society found that long-term exposure increases an individual’s risk of death from respiratory distress.
Smog is the most worrisome form of air pollution for many reasons, but there are other sources of air pollution that independent of being part of smog can cause many health problems.
Effects of Various Pollutants:
An article at Love to Know summarized some of the health risks from various pollutants, including some of the common components in smog. The Environmental Protection Agency summarizes the potential health problems associated with a variety of pollutants:
Nitrogen dioxide – The most common source of exposure to this chemical is automobile exhaust. Chronic exposure to this pollutant can cause lung irritation and can reduce the body’s ability to fight respiratory infections.
Sulfur dioxide – This product of coal burning and volcanic eruptions can cause acid rain. Exposure to this chemical can worsen breathing problems and increase the risk for cardiovascular disease.
Volatile organic compounds – Fossil fuels, paints, stains, construction, and other sources introduce hydrocarbons into the air. These compounds can be a health concern inside and outside. Headaches and eye, nose, and throat irritation can result. People with respiratory problems are likely to suffer more serious side effects. Exercising in air contaminated by chemicals would only exacerbate the effect because people take in much more air.
Carbon monoxide – This common product of burning fossil fuels is a major issue in urban areas because of its toxicity. Neurological problems and visual impairment can result from acute or chronic exposure to carbon monoxide.
Lead – Lead contamination in the air became far less of a concern when lead was removed from gasoline, but people living downwind of certain factories, those that make lead-acid batteries for example, can still inhale lead. The EPA warns that lead exposure can cause kidney disease, anemia, neurological problems, high blood pressure, osteoporosis, and reproductive disorders.
That list makes it clear that pollution from motor vehicles, factories, and power plants exposes people to numerous health risks.