• Ozone (O3)

Ozone is the primary ingredient in smog and forms when hydrocarbons and nitrous oxides react with sunlight। Not all ozone is bad, in fact, like carbon dioxide, it is quite beneficial in the upper atmosphere as it keeps harmful ultra-violet light out, a major cause of skin cancer. It becomes a problem when it hovers in the lower atmosphere where it can enter the lungs. Ozone inhalation can produce coughing, choking, and reduced lung capacity. It can also worsen chronic respiratory diseases such as asthma and compromise the body's ability to fight off respiratory infections. Recovery from short-term exposure to ozone can occur, but longer exposure may make recovery less certain. Although ozone is not directly related to anything we may use, it does form when nitrous oxides and volatile organic compounds react with sunlight.