We come into the world with the first breath and leave with the last exhalation. Breathing is something many of us take for granted - giving little or no thought to the effort required.

This is not the case for those who suffer from asthma. Children who have asthma don´t take breathing for granted. Tightness in the chest, wheezing and coughing are familiar signs that an asthma attack is imminent. Narrowed airways caused by swelling of the lining, tightening of the muscle, and increased secretion of mucus in the airway make breathing difficult as the familiar wheezing begins. Without quick relief, distress and panic can cause further tightening of the muscles and narrowing of the airways. For a child, this can be a very frightening, debilitating experience.

Asthma attacks can be life-threatening. Although the airway obstruction and hyperactivity of the lung usually can be reversed, the inflammation underlying asthma is often continuous and can be aggravated, and possibly caused, by air pollution. When lungs are irritated by air pollution, they become more sensitive and responsive to other allergens, which can lead to asthma attacks.

Studies show that the number of children in the United States afflicted with asthma has increased dramatically: The U.S. Center for Disease Control and Prevention reports that between 1980 and 1994, the number of children under age four afflicted with asthma grew 160 percent; and according to Western Michigan University Office of Health Promotion and Education, the number of school-age children with asthma increased 100 percent from 1980-1998.

The American Lung Association estimates that more than six million children under 18 have asthma. Asthma is the third leading cause of hospitalization among children under the age of 15, and it is the most prevalent chronic condition among children. In 1999, there were about 658,000 pediatric emergency room visits due to asthma.

Children in Houston may be at an even higher risk than in other U.S. cities. A 1999 survey of 21,000 children in Houston Independent School District found that 10 percent have asthma or asthma-like symptoms - double the national rate.

A study by the Pew Environmental Health Commission on the increasing incidence of asthma in the United States found that genetics "load the gun" for a predisposition for asthma, but it is the environment that "pulls the trigger" on the shocking growth of this disease.

"Air pollution is not benign," says Stephen King, PhD, a Houston toxicologist, epidemiologist and clinical ethicist. "It is a significant health issue that poses a risk of debilitating respiratory disease."

Based on a number of studies, it appears that the four outdoor air pollutants most likely to aggravate asthma are ozone, sulfur dioxide, nitrogen dioxide and particulate matter, although air toxics have been implicated in some studies as well.

Ozone may even cause asthma. A recent study to assess risk of asthma in children playing team sports in communities with high ozone, low ozone and in communities with other air pollutants concluded that “incidence of new diagnoses of asthma is associated with heavy exercise in communities with high concentrations of ozone, thus, air pollution and outdoor exercise could contribute to the development of asthma in children”(The Lancet, vol. 359, no. 9304).

The hazards of ozone and other air pollutants pose a greater risk for children than adults because they are outdoors more, especially in the summer; they are more active; they breathe more rapidly; they breathe through the mouth; and their lungs are still developing.

Unfortunately, the perfect day for outdoor activities - a day with clear blue skies, calm winds and warm temperatures - is also the perfect day for ground-level ozone to develop. The sunlight (UV rays) and heat act as a catalyst for nitrogen oxides (NOx) and volatile organic compounds (VOCs) from petrochemical plants, refineries and automobile emissions in the air to create ozone.

The facts about the effects of air pollution on children should be more alarming than the recent SARS scare. But rarely does this health crisis make news headlines. The Houston television stations report ozone levels sporadically - usually only on the highest ozone days. Much of what is being spewed out of the petrochemical plants and refineries in this area is under-reported.

What you can do to protect your children More than 80 percent of ozone warning days occur between June and October. To protect children from harmful levels of ozone go to www.cleanairaction.org to check current ozone levels, or to register to receive ozone warnings via e-mail.

The American Lung Association suggests:

• If air quality is unhealthy, limit the amount of time your child spends outdoors in vigorous play. Plan the most strenuous activities for early morning hours before ozone levels climb.
• Keep all outdoor activities as far as possible from busy roadways and other sources of pollution. Make certain your child is never exposed to cigarette smoke, indoors or outdoors.
• Make sure coaches and camp directors are aware of the health risks of air pollution and have policies in place to protect children when air quality is unhealthy. If you child has asthma, let care givers know he or she is especially vulnerable on high ozone days.
• Speak out in support of clean air. National and local leaders need to hear from people who are concerned about the toll air pollution is taking on the health of our children.
• To contact the Houston City Council, go to the City of Houston Government Center web site at www.ci.houston.tx.us/citygovt/council . The site has phone numbers and E-mail listings for each council member.
• Or write to your Council Member at: 900 Bagby, City Hall Annex Floor, Houston, TX 77002.

For contact information on your state and national representatives, go to “Find Your Incumbent” at www.capitol.state.tx.us/fyi/fyi.htm .