Ozone - How does the ozone layer affect my health?

Ozone is a gas that occurs in two layers in the sky. It can be "good" or "bad" for your health and the environment. This depends on where it's located. The layer closest to the Earth's surface is the troposphere. Here, ground level or "bad" ozone pollutes the air. It is harmful to breathe and damages crops, trees, and other plant life. Bad ozone is one of the main parts of urban smog. It is of greatest concern during the summer months because strong sunlight and hot weather result in harmful ozone levels in the air we breathe. Many urban and suburban areas have high levels of "bad" ozone. Breathing in "bad" ozone can trigger many health problems, such as:

  • chest pain
  • coughing
  • throat irritation
  • congestion

It can worsen bronchitis, emphysema, and asthma. Being exposed over time can even scar lung tissue. Healthy people also have problems breathing when exposed to ozone pollution. Because ozone forms in hot weather, anyone who spends time outdoors in the summer may be affected. This includes children.

The troposphere extends up about six miles. Here it meets the second layer, or the stratosphere. The stratosphere or "good" ozone layer extends upward from about six to 30 miles. It protects us from the sun's harmful ultraviolet, or UV rays. “Good” ozone is made naturally. But man-made chemicals can destroy it. The substances that destroy it were mostly used in the past in coolants, pesticides, and fire extinguishers. Once released into the air, these substances break down very slowly for years. When they reach the stratosphere, the sun's ultraviolet (UV) rays break them down. This destroys “good” ozone and causes higher amounts of UV rays to reach the Earth. This can lead to more cases of skin cancer, cataracts, and impaired immune systems in people. UV can also damage sensitive crops, such as soybeans, and reduce crop yields.

How can I protect my family from the harmful effects of ozone?

Through the Clean Air Act, the Environmental Protection Agency (EPA) sets limits on how much of a pollutant can be in the air anywhere in the United States. This helps to make sure that all citizens have the same basic protection. But there are still things you can do to help keep yourself and your family safe.

  • Protect yourself and your children against sunburn. When the UV index is high or very high, limit being outside between 10am and 4pm. This is when the sun is most intense. Apply a sunscreen with a SPF (sun protection factor) of at least 15, twenty minutes before going outside. Put on more sunscreen every two hours or after working or playing. Even waterproof sunscreen can come off when you towel off, sweat, or spend lots of time in the water.
  • Wear a hat with a wide brim to protect your eyes, ears, face, and the back of your neck from the sun.
  • Wear tightly woven, loose-fitting, and full-length clothing to protect yourself.
  • Wear sunglasses that provide 99-100% of UVA (rays not absorbed by ozone) and UVB (rays from the sun which have harmful effects) protection to reduce your chance of cataracts and other eye damage.
  • Avoid sunlamps
  • Check the air quality forecast in your area. At times when the Air Quality Index (AQI) is unhealthy, limit being outdoors to times when ozone levels are not as high. In many places, ozone peaks in mid-afternoon to early evening.
  • Conserve energy at home and in the office.
  • During the summer, fill your gas tank during the cooler evening hours.
  • Reduce driving. Carpool and use public transportation when you can. Walk or bike to reduce ozone pollution, especially on hot summer days.
  • Read labels for proper use of household and garden chemicals.

What is global warming?

Global warming is an increase in the Earth's average temperature. This, in turn, causes climate changes. A warmer Earth may lead to changes in rainfall patterns and a rise in sea level. It also triggers a wide range of changes in plants, wildlife, and human life. Hotter weather increases “bad” ozone and cause more cases of heat-related problems.

Many common things you do at home and on the road add "greenhouse gases" to the air. These gases, such as carbon dioxide and methane, trap the heat of the Earth. Just by starting your car and turning on a light, you could be adding to the levels of these gases in the air.

There are things you can do to help protect the environment. These climate savers will reduce your energy use and decrease the levels of greenhouse gases. Find out how your daily life affects global warming and what you can do. Use EPAs Personal Greenhouse Gas Calculator.

Should I be concerned about haze?

When sunlight comes into contact with tiny bits or particles of pollution, this causes haze in the air outside. Haze reduces the clearness and color of what we see. Motor vehicles and burning fuel release haze-causing pollution. Other gases released into the air and carried by wind many miles from the pollution source can form haze.

Serious health problems have been linked to some pollutants that cause haze. Breathing problems and even death can also happen after being exposed to very small amounts. In scenic parks and wilderness areas, haze has reduced how much we can see.