A Smoking Gun

Dirty Air and the Growing Asthma Epidemic

Posted: 04-May-2004; Updated: 13-Feb-2007

Any mother who has seen her child suddenly start wheezing and gasping for breath and had to rush the child to the emergency room knows what a terrifying disease asthma can be.

Asthma is the nation's fastest-growing chronic disease. The number of Americans with asthma has more than doubled in the past 15 years, with more than 20 million asthma sufferers today. Especially disturbing is that asthma rates among children under age four have skyrocketed over the past two decades (jumping 160% between 1980 and 1996). Even if these worrisome trends are stabilized, we still have a critical public health problem on our hands.

This week marks World Asthma Day (May 4), a time to raise awareness and educate people about not only managing the disease but also how to prevent it in the first place. Exactly what causes individuals to develop asthma is not known for sure, but research suggests the disease results from a complex interplay between genetic makeup ("loading the gun") and exposure to infections and critical environmental factors in the first years of life ("pulling the trigger").

Environmental factors also trigger asthma attacks. In addition to allergens (like pollen or dust) and indoor pollutants (like tobacco smoke), we know that the outdoor pollutants smog and soot can set off an attack, and some studies suggest that exposure to diesel pollution and ozone (a main component of smog) may even cause asthma in some cases. 

Smog and tiny sooty particles pose particular health problems. Besides triggering asthma attacks, breathing in ozone can singe your lungs much like a sunburn, and repeated exposure over years can cause permanent lung damage. Children are especially vulnerable because their lungs are still developing and because they tend to be active outside during smog season (generally May through September). Breathing in air heavy with tiny particles can be dangerous even over a short time; because these particles are so minuscule, they can enter the circulatory system and damage blood vessels.
 
"Although smog and soot are are linked to a host of health problems from cancer to premature death," says John Balbus, M.D., M.P.H., director of the Health program at Environmental Defense, "asthma is perhaps one of the most visible diseases worsened by air pollution, with asthmatic children particularly hard hit. Just as we would not allow our child to smoke a cigarette, we should not allow our children to keep breathing dirty air. Of the many triggers of asthma air pollution is one thing we can clearly do something about."

Attacking the Problem

Environmental Defense is attacking the asthma epidemic on many fronts, working to clean up the toxic emissions that spew forth from smokestacks and tailpipes. One major source of harmful air pollution is diesel exhaust -- that unmistakable, black sooty cloud of smoke billowing from schoolbuses and trucks. That cloud is a dangerous mix of fine sooty particles, smog-forming pollutants (such as nitrogen oxides) and cancer-causing chemicals (benzene, for one) - and is actually dirtier than exhaust from gasoline-powered engines.

While tighter emissions rules governing some diesel-powered engines like those in trucks and buses (or "onroad vehicles") are scheduled to go into effect by 2006, nonroad diesel-powered engines (such as tractors and locomotives) have not been regulated. This month EPA is expected to announce new rules for nonroad engines that are expected to cut pollution by 90%.

But the benefits of the new EPA rules won't be felt throughout the market for at least 20 years, since diesel engines stay in use for decades. Technologies are in place to cut emissions from existing engines now, and many areas hard-hit by asthma are stepping forward to take advantage of them.

States Take the Lead

Spurred by an Environmental Defense report, California recently passed tighter rules for regulating emissions from diesel-powered backup generators, paving the way for possible nationwide rules regulating these emergency sources of power. In December 2003, New York City enacted a law that requires the use of best available retrofits and low polluting fuels in all city public works construction contracts. New York State has pledged to carry out similar measures in the reconstruction of the World Trade Center. And with assistance from Environmental Defense, Texas recently committed to spend $150 million a year to retrofit and clean up diesel engines on a broad range of fleets, including school buses. 

"Cities and states across the country are taking matters into their own hands to clean up dirty diesel engines in cost-effective ways," says Andy Darrell, co-director of Environmental Defense's Living Cities program. "By doing so, they are showing the need for a national commitment to clean up school buses, construction machinery and every other source of diesel emissions that plagues our communities today."

Healthy Air for Everyone

Yet despite much progress in cleaning up our air since the advent of the Clean Air Act over 30 years ago, more than half our country's population is still breathing unhealthy air, and many large metropolitan areas are still enveloped in smog. This month the Environmental Protection Agency announced its designations of ozone "nonattainment" areas -- those that do not comply with EPA's tougher health-based ozone standards issued in 1997, after mounting scientific evidence conclusively showed that lower levels of smog and soot are more harmful to health than previously recognized. (EPA had failed to enforce the new standards until Environmental Defense and other groups took legal action.)

EPA recently declared that 474 counties in 31 states had failed to meet the new ozone air-quality standards, including such areas as metropolitan Los Angeles (listed as severe), the San Joaquin Valley (serious), Houston (moderate) and Chicago (moderate).

On the heels of EPA's designation came the American Lung Association's annual State of the Air Report 2004, which ranks metropolitan areas and counties by the most polluted and cleanest (based on EPA data) for not only ozone but also fine particles (which are included for the first time). (For rankings and to read the report, click here.)

 "The good news is that millions more people, including individuals with asthma, will eventually benefit from clean air," says Environmental Defense attorney Vickie Patton. "But the bad news is that EPA left off some counties that should have been included. Another concern is that some areas that had gained momentum toward coming into compliance under the pre-existing ozone health standard now have essentially been given an extension, a new deadline, to meet the more protective standard." 

For example, Los Angeles originally had until 2010 to clean up its act, but now it need not meet the new standards until 2021. And for Dallas/Fort Worth, it was 1999 versus. 2010. "While we understand that a little more time is needed to make adjustments, these delays will mean that another generation of kids will have to breathe unhealthy air," adds Patton "A four-year-old child should not have to wait until she is 21 before she can breathe healthy air." 

On World Asthma Day, we must also call attention to the widespread undermining of our nation's clean air laws that is under way.  With a thousand cuts large and small, the very laws that have achieved substantial progress in cleaning up the nation's polluted air are being degraded and weakened -- for example, the dismantling of the New Source Review program under which older power plants that substantially upgraded or expanded their facilities would have to also upgrade their pollution control equipment.  

Now more than ever we need to not only protect the significant gains we've made in cleaning up our air but move forward on ensuring clean, healthy air for everyone.

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