Connecticut’s Department of Energy and Environmental Protection (DEEP) is forecasting unhealthy air quality for “sensitive groups” Thursdays through Saturday, July 20, due to predicted elevated concentrations of ground-level ozone pollution.

The highest levels of ozone will likely occur across south central and southeastern coastal Connecticut today, Thursday July 18th.  This area of unhealthy air quality for “sensitive groups” is forecasted to expand into further inland Connecticut on Friday July 19 and Saturday July 20.

A forecast of “Unhealthy for Sensitive Groups” indicates increased likelihood of respiratory symptoms and breathing discomfort in active children and adults with respiratory disease, such as asthma and the elderly.

Unhealthy concentrations of ground level ozone can cause or make worse a variety of respiratory and other health problems including breathing difficulty, coughing, and throat irritation and worsen asthma episodes. Anyone can be affected by ozone; particularly sensitive groups that include children, elderly, people with respiratory disease, such as asthma, and even healthy adults who are very active outdoors.  These sensitive groups who experience effects at lower ozone concentrations are likely to experience more serious effects at higher concentrations; and should avoid strenuous outdoor activities and consider remaining indoors in an air conditioned environment.

Ground level or "bad" ozone is created when two types of air pollutants, nitrogen oxides (NOx) and volatile organic compounds (VOC), react in the presence of sunlight and warm temperatures, according to the DEEP. These air pollutants are generated both inside and outside of Connecticut from industrial facilities and electric utilities, motor vehicle exhaust, and gasoline vapors.  Air pollution is also transported into Connecticut on prevailing westerly winds from the Ohio River Valley and from the southwest along the I-95 urban corridor from Washington D.C.