Wednesday, June 27, 2001

Smog poses danger to summer fun in the sun

Summer is here and it's time to go play outside. The last thing anyone wants to hear this time of year is that outside physical activity at the wrong time of day can be harmful. But ozone, a component of smog, is more prevalent during the summer months and poses serious health hazards.

Smog, the brown-orange gas composed of small bits of dust, soot, aerosols and other substances that lies over many urbanized areas, reacts with the lungs and throat resulting in breakdown and irritation of the tissue.

Rob Schreiner, M.D., a Kaiser Permanente physician at Glenlake Medical Center, says that effects of smog can lead to damage to the respiratory system, reducing lung capacity and possibly causing permanent lung damage following repeated exposures.

Patients with chronic lung conditions, such as asthma and emphysema, are at greatest risk to the short-term effects of somg. These patients may experience sudden and severe flareups of their diseases. It has also been shown that in large cities throughout the world, the death rate from cardiovascular disease increases substantially on days of high air pollution.

During exercise or strenuous work a person breathes more air and draws it deeply into the lungs, said Dr. Schreiner. And when a person exercises heavily, he or she breathes mostly through the mouth, bypassing the body's first line of defense against pollution, the nose.

Children are especially susceptible to the effects of smog. They spend significantly more time outdoors, especially in the summertime, when ozone levels are the highest. In addition to spending more time outdoors playing, children have a higher breathing rate than adults do relative to their body weight and lung surface area. As a result,children get a greater dose of pollution.

In order to be protected from the damaging effects of ozone, parents and their children should reduce the time they spend on activity that requires heavy exertion or substitute another activity that requires more moderate exertion (such as going for a walk rather than a jog). In addition, they can plan outdoor activities when ozone levels are lower, usually in the morning or evening.

Fitness levels vary between individuals and children, but cutting back on the level or duration of exertion when ozone levels are high will help protect parents and their children from ozone's harmful effects.