Climate change and health

What is Ozone?

Ozone is the main component of smog and is one of the most dangerous forms of air pollution. Ozone is not emitted directly into the air, but rather forms when emissions of gases including nitrogen oxides (NOx), volatile organic compounds (VOCs), carbon monoxide, and methane “cook” in the sun. Ground-level ozone, or smog, is worse in the summertime because sunlight and hot weather accelerate its formation. This means that during summer break seasonal smog alerts often urge children to restrict their activity or stay inside to avoid respiratory effects like asthma.

Ozone comes from sources such as coal-fired power plants, automobiles, industrial facilities, gasoline vapors, and chemical solvents. Coal-fired power plants are among the largest sources of smog-forming pollution, with more than 500 plants currently operating in our country, many of them lacking modern pollution controls.

Motor vehicles also account for a huge percentage of smog. On-road vehicles are responsible for more than 35% of NOx emissions and nearly 26% of VOC emissions in the U.S.

The Health Effects of Smog

Ozone is harmful to human health even at very low levels. Smog doesn’t just ruin your view; it poses serious health risks, especially to children and senior citizens. Smog can cause:

• Asthma
• Reduced lung function
• Airway irritation and damage
• Increased susceptibility to respiratory infections
• Permanent lung damage (Scientists have compared exposure to smog pollution as getting sunburn on the lungs)
• Shortness of breath and chest pain
• Wheezing and coughing
• Increased treatment or hospitalization of people with lung diseases, such as asthma or chronic obstructive pulmonary disease (COPD) including emphysema and chronic bronchitis
• Premature death

Children are at increased risk from exposure to ozone because their lungs are still developing and they are more likely to be active outdoors.