REPORT BY PAUL J. LIOY, PhD

ENVIRONMENTAL AND OCCUPATIONAL HEALTH SCIENCES INSTITUTE 1989

WHAT IS OZONE?

Ozone is a word we link with air quality. Many of us may be confused when we hear that high levels of ozone in the air we breathe are bad for our health, yet not enough ozone in the upper atmosphere is also harmful . The difference is the effects caused by the ozone being present at ground level, or absent in the upper atmosphere.

Ozone is a gas made up of three oxygen atoms. The oxygen we normally breathe is two oxygen atoms. We can find ozone in the air around us, as well as far above us In the atmosphere. First we will discuss ground level ozone.

GROUND LEVEL OZONE

Ozone at ground level is air pollutlon, commonly called smog. It is formed when nitrogon oxides from cars, power plants and industrles combine with hydrocarbons. The hydrocarbons are given off from sources such as cars, gas stations, large and small industries, and commercial processes that use solvents, such as dry cleaning. Sunlight starts the reactions of these pollutants to form ozone. Because sunlight aids chemical reactions, smog levels are higher from May to September.

WHAT HEALTH ISSUES MAY RELATE TO GROUND LEVEL OZONE?

Ozone can cause iritation of the throat and lungs, tightness of the chest, pain and difficulty in breathing, wheezing, and coughing . This can happen at the high levels of ozone found for one or more hours on a sunny, hazy day during the summer. Areas near cities usualiy have the highest levels of ozone. H owever, high levels can also be found in many suburban and rural areas. People who are most at risk from the short term health effects of ozone are children, the elderiy, and people wlth asthma or other lung diseases. Health effects are greatiy Increased by exercising outdoors durlng hot, hazy, sunny days with smog. This can affect healthy people as well.

There is concern among the health experts that exposure to ozone over time may permanenty reduce the lung's ability to work. This can lead to long-term lung damage. Regarding the environment, studies by ecologists show that higher levels of ozone can reduce the yields of some crops.

In New Jersey, ozone levels are highest during the dayti me hours and/or in the early evening. The sunlight is Interacting with pollutants to form ozone during mid-day, which can travel great distances downwind by evening. Therefore, outdoor activities such as exercising or manual labor should be limited on days with high ozone levels. On such days, activities should be confined to the eariy morning hours or later In the evening, Ozone levels will remain high when there are several hot sunny days in a row. Cool, clear or rainy or cloudy days permit the ozone levels to decrease.

WHAT CAN BE DONE TO PREVENT OR CONTROL RELATED HEALTH HAZARDS?

The Clean Air Act (CAA) is federal legislatio n that sets limits on how much pollution Is allowed in the air. It requires the motor vehicle industry to reduce pollution caused by cars, trucks and buses, and limits emissions from industrial plants.

Although the CAA has Improved the nation's air quality, it has not been effective in keeping ozone at healthy levels. The CAA requires states to meet standards for ~criteria pollutants.~ These pollutants are substances that are especially harmful to health. The standard for ozone allows for 0.12 parts per million at a daily one-hour average. This means that no more than an average of 0.12 parts of ozone to one million parts of air can be present in a given hour. Recent research, however, suggests that the standard should be lower In order to lessen the harmful health effects from ozone.

Many areas of the country have not been successful in meeting the standards allowed under the CAA. The U.S. government Is attempting to reauthorize the CM so this public problem can be reduced. Continuing areas are California and the northeastern states, including New Jersey. California has taken steps to reduce emissions. The northeastern states are making plans which would Involve cooperation among those states. Some plans include:

adopting stricter re gulations for emissions from new cars, as California has done;

have refineries lower the volatility, or evaporation rate of gas;

reducing hydrocarbons from products such as hairsprays, household solvents, etc.
Two actions already implemented in New Jersey are to Install vapor recovery systems on gas pumps, and reduce gasoline volatility. Vapor recovery systems capture escaping gas vapors and recycle them . Gas vapors are sources of hydrocarbons. Neighboring states must take the same measures as New Jersey to truly reduce the ozone levels.

WHAT ELSE SHOULD I KNOW ABOUT GROUND LEVEL OZONE?

Tackling this problem requires effective enforcement and compliance with the CAA. Industries can make an Impact by reducing chemical emissions, and developing products which are environmentally sound. Consumers can also act to protect the air. Car emissions are a source of nitrogen oxides . Keep motor vehicles tuned up . Reduce use of cars whenever possible. Carpooling, public transportation, walking and bicycling are helpful alternatives.

Solvents are sources of hydrocarbons. Use water-based or solvent-free paints Instead of oil-based or solvent-based plants. You should avoid household solvents such as furniture stripper and paint thinner. Keep all solvents Highly sealed to avoid evaporation.

STRATOSPHERIC OZONE

Ozone also exists In the upper atmosphere of earth, which is called the stratosphere. The stratosphere is found 10 to 25 miles above us. Here ozone acts as a permanent protective layer which screens out the sun's harmfulul ultraviolet rays. This upper ozone Is formed naturally when the sun reacts with natural nitrogen compounds. The current problem is That chemicals known as chlorofluorocarbons (CFCs) are depleting the ozone layer. This leaves us with less protection from the sun's ultraviolet rays. CFCs are used In foam products, such as foam packaging and furniture . They are also used as coolants In air conditioners and refrigerators. CFCs have longlasting qualities so when they are released into the environment, they remain Intact. These molecules travel to The upper atmosphere where the atoms Interact with the ozone, changing Its make-up.

WHAT HEALTH ISSUES MAY RELATE TO STRATOSPHERIC OZONE?

There are also health effects from the ozone problem In the upper atmosphere. As The ozone layer is becoming depleted, we are receiving more ultraviolet radiation from the sun. Th is radiation is known to cause skin cancer. Recent stud ies show that ultraviolet radiation is aiso harmful to plants, which can lead to loss of crops.

WHAT CAN BE DONE TO PREVENT OR CONTROL RELATED HEALTH HAZARDS?

Protection against skin cancer means blocking out the harmful rays of the sun . When outdoors for extended periods, wear comfortable clothing and hats to block the rays from the skin. In the summer, be aware that excessive exposure to the sun will occur between 10:00a.m.and2:00p.m. When at the beach, use lotions with sun protecton factor of at least 15.

WHAT ELSE SHOULD I KNOW ABOUT STRATOSPHERIC OZONE?

The upper ozone problem also requires cooperation by legislatur es, Industries and consumers. As the upper ozone is aglobal problem, a global solution is required. Two dozen countries signed a treaty That aims to save the ozone layer. The Montreal Protocol calls for nations to reduce CFCs by 50% before The end of the century, however, more reductions appear necessary.

Chlorofluorocarbons are used In foam blowing for food and other packaging: cushions and building Insulation; and solvents used to clean semiconductors and other computer components and refrigerants. Research Is under way to develop alternatives to CFCs.

You can reduce CFC use by replacing car and truck air-conditioner hoses every three years. Ask the mechanic to drain the coolants Into bottles rather than discharging them Into The environment. Most of the rigid foams found in egg cartons and coffee cups used CFCs. Many companies have now taken the CFCs out of these products. Currently there is no way for consumers to know if CFCs are in the foam packaging. It is better to buy products packaged In non-foam materials, preferably materials That can be recycled In your community. Halon fire extinguishers also contain chemicals harmful to the ozone layer. Instead, buy traditional fire extinguishers for home use.

WHERE CAN I FIND FURTHER INFORMATION OR ASSISTANCE?

The New Jersey Departments of Healthh (DOH) and Environmental Protection (DEP) Issue radio bulletins in the summer when high amounts of ground bvel ozone are measured or expected. Also, DEP has a toll free llne for Air Quallty Reports. A recorded daliy air quality reports avallable by calling 1800-782-0160, Monday through Friday beginning at 10 a .m., year round. Other states may also have air quality hotlines. Contact you state environmental agency.

The American Lung Association (ALA) has several publications on air pollution and health, Includlng a pamphlet on air pollution and exercise. Contact your local ALA.

ProJect Clean Alr of the Regional Pian Assoclation does outreach and education on air quality problems In New Jersey. and they recommend approaches for soluti ons. Thelr address is 60 Park Place. Suite 1603, Newark, NJ 07102, 1 -201 -623- 1133.

Information on ground level ozone is available from Public Affairs Office, US EPA, Research Triangle Park, NC 27711, 1 -919-541 -4577.

For Information on stratospheric ozone, contact Natural Resources Defense Council,40 W.20t hSt., New York, NY 10001, 1-212-727-2700. They have avallable A Citizen's Action Guide for information on the ozone layer. The Environm ental Defense Fund,257 Park Ave . South, New York, NY 10010,1 -212-505 2100 has a booklet, Protecting the Ozone Layer, available for S2.00.