The Nassau County Department of Health's air pollution laboratory in Hempstead has started its seasonal reporting of ozone pollution. For current ozone readings or additional information regarding ozone, call the Department's Public Health Laboratories' 24-hour line at 572-1200.

Although ozone in the upper atmosphere performs an important protection function by filtering out harmful ultraviolet radiation from sunlight, ozone near the ground is a pollutant. It is a highly reactive gas and is one of the components of smog.

Ground level ozone is a health concern because high concentrations may irritate nasal, throat and bronchial tissues.

Those who are especially sensitive to the effects of ozone exposure include the very young, the elderly and people with heart or respiratory ailments. Respiratory symptoms resulting from ozone exposure may include shortness of breath, chest pain, throat irritation, cough and wheezing.

When the average ozone concentration over an eight hour period is greater than 0.08 parts per million, persons at risk should take precautionary measures, such as avoiding strenuous exercise and outdoor exertion, to limit their exposure.

In addition, the New York State Department of Environmental Conservation (DEC) constantly monitors ozone levels throughout the state and issues health advisories in cooperation with the New York State Department of Health when they predict elevated ozone levels. The advisories are aired through the media and available on the New York State DEC toll-free Ozone Hotline telephone number: 1-800-535-1345.