Why is Air Quality an Issue in DeSoto County, Mississippi?

Air Quality is an issue which is not confined to our county or our state but concerns our region and our nation. Not only does air pollution affect our ability to enjoy clear blue skies, air pollution can affect our economy and even our health. By learning more, getting involved and even making some simple changes to our lives, we can each do our part to keep our skies blue and future healthy.

What Is Air Pollution?

When people talk about air pollution or “smog”, they are referring to one of two pollutants: ground-level ozone or particle pollution.

Particle pollution is the term for a mixture of solid particles and liquid droplets found in the air. These particles come in many sizes and shapes and can be made up of hundreds of different chemicals. Some particles are emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks or fires. Others form in complicated reactions in the atmosphere of chemicals such as sulfur dioxides and nitrogen oxides that are emitted from power plants, industries and automobiles. For more information on particle pollution, see the EPA's website at http://www.epa.gov/.

Because of recent headlines and new regulations by the EPA, this site is aimed more at providing information on the other primary source of air pollution, ground-level ozone.

Facts About Ground-Level Ozone

• Ground-level ozone is a colorless, highly reactive gas that is formed when nitrogen oxides (NOx) and volatile organic compounds (VOCs) come into contact with heat and sunlight.
• Given the importance of heat and sunlight, ozone is principally a summertime problem. It is for this reason that May through September is referred to as “Smog Season”.
• VOCs are associated with sources that emit strong fumes and vapors. Gasoline, oil-based paints and solvents are all sources of VOCs. Trees and vegetation are natural sources of VOCs.
• NOx (pronounced “knocks”) is created through the combustion process associated with engines and boilers. Sources of NOx in DeSoto County include cars, trucks and non-road vehicles (including construction equipment).
• Highest ground-level ozone concentrations occur between 1 and 6 p.m.

When we breathe in ozone, it can inflame the lining of the airways and lungs. The most common symptoms associated with ozone exposure are a feeling of chest tightness, dry cough and difficulty breathing. Emergency room visits for asthma and other respiratory problems spike whenever there is a high level of ground-level ozone. Since the highest concentrations occur in the afternoon and evenings, you can avoid exposure to ozone even on Ozone Alert days by performing outdoor activities like running in the mornings.

How is Air Quality Regulated and What is the Government’s Role?

The United States Environmental Protection Agency (EPA) is a federal agency with the mission to protect human health and the environment. Since 1970, the EPA has implemented a variety of programs under the Clean Air Act that, among other things, seek to reduce outdoor concentrations of air pollutants, including ground level ozone. Since air pollution is a problem not restricted by state or local boundaries, participation at all levels of state and local government and by all citizens is necessary to ensure we all get the benefit of clean air. For their part, the Mississippi Department of Environmental Quality (MDEQ) and Desoto County work closely together to monitor compliance with EPA standards, to implement local policies to reduce emissions and to encourage participation by residents in individual behaviors aimed at improving air quality.

How can I make a difference?

On an individual level, since our personal vehicles are probably the highest contributing source to ground-level ozone that we control, the most dramatic impact each of us can make involves our driving habits. Driving less, sharing rides, making better choices in maintaining or choosing vehicles: these are some of the easiest ways to lessen sources of NOx which contribute to the formation of ground-level ozone. Please visit the Useful Tips link to learn more about making small changes which can dramatically affect sources of NOx in our local air. However, the most important thing we can all do is to become more educated and informed about the problem and ever-changing solutions. We have provided the most important links on this issue where you, the citizens of Desoto County, can learn more to keep our skies blue and our children healthy.

Useful tips and steps you can take to do your part:

Tackle Your Trips: Plan ahead to combine several errands into one trip, or run errands on the way home from work. Run groups of errands in the evening hours, since the impact of emissions is worse during hotter hours.

• Get Children on Board: Encourage children to ride the school bus, or organize a "school pool" - a carpool with other parents. Share after-school driving and take turns driving children to sports practice, swim lessons, music lessons, etc.
• Use Technology: Use the phone and the Internet to locate or purchase products and services, instead of driving from store to store.
• Make a Smart Vehicle Choice: Evaluate gas mileage and air pollution ratings for new and used cars and trucks. Consider a hybrid for your next purchase.
• Make Maintenance Top Priority: Keep your engine tuned, tires inflated and replace your air filters regularly. A tune up can increase your gas mileage by an average of 4.1 percent, while a new air filter can improve it by up to 10 percent.
• Turn it Off: Whenever you are driving, remember to turn off your car instead of idling for long periods. Extended idling causes greater wear and tear on your car, wastes fuel, in addition to adding pollutants to the air. Avoid drive-thru lanes and walk inside instead.
• Refuel After 6 PM: Fill up your gas tank in the evening rather than the morning. Evaporative emissions from morning gasoline fill-ups contribute to air pollution, particularly during the summertime.
• Check Your Gas Cap: Leaking gas caps contribute to air pollution and waste fuel due to evaporation. Every leaking gas cap equals approximately 200 pounds of evaporative emissions each year. Up to 300 gallons of gasoline can be released annually - that's a lot of money wasted.

What impact does a single car have on pollution and air quality?
The average passenger car emits more than 115 pounds of smog-forming emissions each year. The average light truck or SUV emits almost 164 pounds of smog-forming emissions annually. Reducing the amount of single-occupant vehicle miles driven is one of the single biggest things we can do to significantly impact air pollution and traffic congestion.

Why refuel after 6 PM?
When you fill up, vapors escape into the air, adding VOCs to the ground-level ozone mixture. By waiting until after the heat of the day, you are contributing less to the chemical soup of pollutants to be cooked by the hot summer sun that produces unhealthy concentrations of ozone.

Useful Links

Mississippi Department of Environmental Quality

Area Air Quality Index

Green Vehicle Guide 

Kids Guide