In 1996, the city of Atlanta took dramatic steps to improve the city's air quality for the summer Olympics. In the process, it showed how reducing air pollution can improve lung function.
What city officials did -- switching to rapid transit and buses that ran on natural gas instead of diesel -- decreased asthma attacks by up to 44% in children and ozone concentrations by 28%, the CDC reported in a study in 2001 in The Journal of the American Medical Association.
Recommended Related to Lung Disease/Respiratory Problems
"It seemed easier to breathe," recalls Carol Lincoln, 44, who attended the summer games. The skies were "bright and blue" instead of "the sooty gray we're so used to," she says. "Things seemed cleaner. It was so obvious that we talked about it."
Study author Michael Friedman, MD, of the CDC says the results showed that reducing air pollution improves lung health. Here's what we know about how the two affect each other:
What are the different types of pollution?
Ozone, the primary component of smog, is created by a chemical reaction that occurs when sunlight interacts with particulates (soot) from motor vehicle exhaust, gasoline vapors, and dust from power plants.
Particulate matter, also known as particle pollution, includes nitrates, sulfates, organic chemicals, metals, and soil or dust particles; it is a complex mixture of tiny particles and liquid droplets.
Nitrogen dioxide, or NO2, is one of a group of highly reactive gasses. NO2 forms quickly from emissions from cars, trucks, buses, power plants, and off-road equipment. According to the Environmental Protection Agency (EPA), this compound reacts with ammonia, moisture, and other compounds to form small particles. These small particles penetrate deeply into sensitive parts of the lungs and can cause or worsen respiratory disease, such as emphysema and bronchitis, and can aggravate existing heart disease, leading to increased hospital admissions and premature death.
Carbon monoxide, or CO, is an odorless, colorless gas formed when carbon in fuel isn't completely burned. Higher levels of CO occur in areas with heavy traffic congestion. It is a component of motor vehicle exhaust, which contributes about 56% of all CO emissions nationwide. Other sources are cigarette smoke, wood and gas stoves, and industrial emissions.
Sulfur dioxide gases are formed when fuels containing sulfur, like oil and coal, are burned, or when metals are extracted from ore. It interacts with other pollutants and can be harmful.
Lead is now mostly found near waste incinerators, utilities, and battery manufacturers. Lead emissions from gasoline have declined by 95% since the EPA began regulating clean air standards more than three decades ago.