BLOG
What’s the Problem with our Air?
Air quality in Georgia has improved dramatically over the past two decades, thanks to a combination of regulatory controls and voluntary programs like the ones offered through The Clean Air Campaign. Presently, all counties in Georgia meet current National Ambient Air Quality Standards designed by the U.S. Environmental Protection Agency (EPA) to protect public health. But these standards are likely to become more stringent in the near future. And population growth in Georgia brings challenges, with greater energy consumption and more cars on the roads creating more air pollution. Across Georgia, 27 counties or parts of counties are classified by the EPA as a nonattainment area for ground-level ozone, particle pollution, or both. This includes 20 counties in metro Atlanta, as well as areas surrounding Macon, Floyd, Chattanooga and parts of the Chattahoochee National Forest.
Nonattainment status means that pollution levels are likely to exceed federal and state limits on many days throughout the year. Exceedances for ground-level ozone are most likely to occur during warmer months, while particle pollution exceedances may occur at any time. Poor air quality threatens economic prosperity, poses risks to human health and is harmful to the environment.
What Is Smog?
Smog, a word that is a combination of “smoke” and “fog,” is a mixture of air pollutants, some that can be seen or smelled, and others that cannot. In Georgia, the two most important pollutants are ground-level ozone and particle pollution.
Ground-Level Ozone
Ozone does not come from tailpipes and smokestacks. Instead, it is a “secondary pollutant”—a byproduct of two other air pollutants, nitrogen oxides (NOx) and volatile organic compounds (VOCs or hydrocarbons).
- Nitrogen Oxides (NOx) come primarily from combustion of fuels in cars and trucks, coal-fired power plants, industrial boilers and gas-powered engines such as lawnmowers and leaf blowers. This occurs because nitrogen—which accounts for about 80 percent of air—also burns (oxidizes) when other fuels are burned.
- Volatile Organic Compounds (VOCs) are vapors that emanate from paint and print shops, gas stations, dry cleaners, lawn chemicals, and from combustion engines, such as those in cars and trucks, boats and diesel locomotives. Trees also emit VOCs.
Sunlight and warm temperatures “cook” NOx and VOCs, which react to form ozone. That is why we see more ozone in the summer, especially in the afternoons and early evenings. Ozone can form at other times if weather is unseasonably warm.
While ground-level ozone is a health and environmental concern, ozone in the stratosphere (six to 30 miles above Earth) is beneficial, as it shields Earth from harmful ultraviolet radiation.
Particle Pollution
Particle pollution (also known as particulate matter or PM), another main component of smog, comes from some of the same sources as NOx and VOCs, including power plants and factories, motor vehicles (especially older diesel vehicles), and others. Particle pollution is also created by wood burning, construction activity and agriculture. Unlike ground-level ozone, particle pollution occurs year-round.
What are the Health Effects of Poor Air Quality?
Ground-level ozone is harmful to health, especially for children, the elderly and those with respiratory conditions such as asthma. The primary target is the respiratory system. Ozone also targets the heart and the immune system. Ozone is a reactive and irritating chemical. When inhaled, it can irritate and inflame the airways that carry air from the mouth and nose to the lungs. Even at low levels, exposure to smog may not cause symptoms, but special tests may reveal inflammation and decreased air flow.
When exposed to particle pollution, people with heart and lung diseases and older adults are more at risk of hospital and emergency room visits, or, in some cases, even death. These effects have been associated with both short-term (as short as one hour) and long-term exposures. Particle pollution side effects include:
- Aggravated heart diseases such as congestive heart failure and coronary artery disease
- Aggravated lung diseases such as bronchitis
- Cardiac arrhythmia
- Heart attacks
- Increased susceptibility to respiratory infections.
Some people are more sensitive to air pollution than others, but at very high smog levels, everyone is at some risk. Everyone should minimize exposure by limiting strenuous activities anytime the air is in the "unhealthy" and "very unhealthy" ranges of the Air Quality Index (AQI). At lower air pollution concentrations, the young, the old, and some individuals with medical conditions affecting the heart and lungs should consider limiting strenuous activity.
How Can I Protect My Health?
People are advised to become aware of their personal sensitivities to air pollution, pay attention to local air quality conditions and act accordingly. Health advisories and/or a personal physician can help people determine their sensitivity to air pollution.
Information about local air quality and the AQI is available from The Clean Air Campaign, reported through many major media outlets and via Georgia EPD’s telephone hotline (404.362.4909). Smog Alerts offer suggestions that individuals, parents/guardians, and institutions such as schools can consider to maintain a healthy exercise regimen while avoiding the unhealthy effects of poor air quality.
Highest ozone levels usually occur from 2 to 7 p.m., primarily during warmer weather months. Though there are peak times for ozone pollution levels, with particle pollution, unhealthy levels can be experienced at any time during a 24-hour period, and affect indoor as well as outdoor air. High particle pollution levels can occur at anytime during the year, although levels are noticeably higher during peak morning traffic.