Ground Level Ozone
Ozone is a colorless gas composed of three atoms of oxygen (O3). Ground-level ozone can trigger a variety of health problems, particularly for children, the elderly, and those people who have lung diseases such as asthma. Breathing ozone can trigger a variety of health problems including chest pain, coughing, throat irritation and airway inflammation. Ozone can reduce lung function and harm lung tissue. Ozone can worsen bronchitis, emphysema or asthma, leading to increased medical care. Ozone at ground level is a harmful air pollutant, because of its effects on people and the environment, and it is the main ingredient in smog. Ozone is most likely to reach unhealthy levels on hot sunny days in urban environments. Though ozone can also be transported long distances by wind, so even rural areas can experience high ground level ozone.