http://www.environmentaldefense.org/article.cfm?contentID=6633
Ask Dr. John Our Chief Health Scientist answers questions on air quality, red alert days and public health Posted on: 07/19/2007 <http://www.environmentaldefense.org/page.cfm?tagID=894> Dr. John Balbus, Chief Health Scientist at Environmental Defense, is a certified medical doctor and public health specialist. We caught up with Dr. John who was kind enough to answer our questions on an all-too-familiar summertime environmental threat: red alert days. What exactly is a "red alert" day and how worried should we be about it? Simply put, a red alert (or "code red") day is a day when the air quality in any given area is forecast to be unhealthy for everyone. There are also code orange days, when the air is unhealthy mainly for people with greater vulnerability, like people with asthma, and code yellow days when the air quality is almost at unhealthy levels. The Environmental Protection Agency sets different standards for different types of air pollution. In the United States, ozone (smog) and fine particles (sometimes called soot) pose the biggest health threats. Local governments publicize red alert days so that people can both take precautions to reduce their exposures to high levels of air pollution and also so they can take measures to reduce their own contributions to air pollution, usually by driving less, avoiding fueling cars and other vehicles, not using power lawn tools, etc. People with poorly controlled asthma and other lung disease or with heart disease have the greatest reason to be concerned about breathing the air on red alert days, because high levels of air pollution can trigger serious problems, like asthma or heart attacks. Even people without these diseases may suffer long-term heart and lung damage from repeated exposure. It seems like there have been more red alert days in recent years. Is that because the problem is getting worse, or are we just paying more attention to it? For most of the country, the number of red alert days each year has been going down, especially when compared to the early and mid 1990's. The EPA has placed stricter controls on power plants and cars and trucks over the past fifteen years. We are seeing the results of these successful measures throughout most of the country. At the same time, recent studies show that smog and fine particle air pollution harms our health at lower levels than we used to think. So breathing the air even on code orange or yellow days could contribute to heart and lung problems. Is this problem caused more by big polluters (smokestacks), individuals on the road (tailpipes) or both? What can I do to help prevent and/or minimize the extent of red alert days? What is the government doing? Both. Big power plants and cars and trucks are all major sources of the pollutants that form ozone and fine particles. Living downwind of a large power plant or near a major roadway can lead to higher exposures and greater health risks, so it's advisable to take extra precaution in these areas. The simplest things people can do are to make fewer trips by car, drive a more efficient car, avoid using gasoline or diesel powered lawn and garden equipment, and conserve electricity in the home. As for the government, the Environmental Protection Agency continues to lower the amount of air pollution allowed from car, trucks and other gasoline and diesel engines. However, the EPA's recent proposed standard for smog pollution doesn't go far enough. In fact, in spite of scientific consensus on the need to substantially strengthen smog standards to protect public health, the EPA has proposed to only marginally strengthen smog standards and has even inexplicably left the door open to leaving the standards unchanged. This is unacceptable and we're calling on the EPA to substantially strengthen this standard ( <http://action.environmentaldefense.org/campaign/epa_ozone_july07> you can join us in taking action). Is there a connection between red alert days and global warming? There are definite links between health-harming air pollution like ozone smog and fine particles and global warming. The first is that both carbon dioxide, the main global warming pollutant, and health-harming pollution share many of the same sources: cars, trucks, power plants, and other things that burn fossil fuels. The second is that warmer temperatures change the chemical reactions that form and transform air pollutants, especially ozone. Other things being equal, hotter air makes more ozone more quickly. Thus, a future with warmer temperatures will probably mean more red alert days, unless we cut back fossil fuel-based pollution more effectively. 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