Smog - An Expert's Perspective

Dr. W. Gerald Teague, M.D., is director, Emory Pediatrics Asthma Clinical Research Center and a recent board member of The Clean Air Campaign. He joined The Clean Air Campaign recently for a Q&A session about air pollution and its impact on health. His advice can help protect your health and the health of your family.

Q: What do you think are the biggest misconceptions concerning air pollution and smog?

A: One of the biggest misconceptions is that an individual can move away from the inner city and then think that they no longer have to worry about air pollution as a health issue. That’s just not true at all. Another misconception is the assumption that if “I’m a healthy person and I don’t smoke and don’t have asthma, then air pollution won’t affect me.” Research shows that even a healthy person can be affected by air pollution.

Q: Do you think Smog Alerts have helped to improve the understanding of the connection between air pollution and public health?

A: Smog Alerts are somewhat of a mixed blessing. On the one hand, people have become more aware that air pollution is a public health issue. On the other, people have come to think that there is this black and white line between clean and healthy air. In reality, there are shades of gray. Some people are impacted at air quality levels far below federal air quality standards. This point is easy to miss when Code Yellow isn’t a Smog Alert but Codes Orange, Red and Purple are.

Q: Has air quality improved in Georgia?

A: People say that air quality has improved, but the complexity of the problem makes such comments problematic.

First, it is true that we have seen a declining number of ozone days over the past five years. However, rainy summers and cooler temperatures have certainly been a factor in the mild summers we’ve seen these past few years. Whether or not this trend will continue is uncertain.

Second, though we have seen some encouraging signs with ozone, we also have cause for concern. In the 1990s, the U.S. EPA defined ozone as a problem affecting the 13 counties of metro Atlanta. More stringent standards for both ozone and particle pollution have compelled EPA to classify an additional 14 full or partial counties in Georgia as “non-attainment.” This term means that these areas “do not attain” the health-based federal air quality standard. Georgia’s non-attainment areas include an expanded 20 county metro Atlanta region as well as areas of middle and north Georgia. So, the problem is expanding to new areas of the state as the regulations catch up with the health-related research. We’ve made some progress over the past 20 years in the case of ozone. However, health-related research suggests we still have a lot of work to do.

Third, the focus on ozone, to me, seems misguided. Particle pollution is the bigger issue. The more I understand about the health impacts of particle pollution, the more I feel we need to rethink how we look at air quality in Georgia.

Q: How so?

A: Particle pollution in Georgia is a year-round problem. It’s a problem indoors as well as out. And, the low level concentrations we see on a daily basis are as important, or possibly more important, than occasional spikes. Particle pollution is tied, not only to respiratory complications such as asthma and emphysema, but also to stroke, lung cancer and heart disease. Given what we are learning about the nature of the problem, we need to do much more to educate the public about both the spikes and the health risks associated with the daily low-level exposure to carbon particles. Both are equally as important.

Q: Do you think it is it important to receive and consult a daily smog alert/air quality index during smog season? Are there any general comments or thoughts you have concerning the smog alert/AQI that you would like to convey to the public?

A: I think Smog Alerts are important, particularly for individuals with chronic lung and cardiovascular diseases. Having said that, I think healthy people should also consult the air quality index. We should all take care of our lungs.

Q: Are there greater health risks for individuals who exercise regularly along busy roadways even in normal smog days? Are those risks greater on high alert days than say running in a park away from vehicles?

A: It probably is worse for a person to run near a busy road. We are just beginning to understand “road dust.” When you are running near a busy thoroughfare you not only are exposed to the pollution already in the air, you are also going to be exposed to particles, tire debris and exhaust emissions at the source, so you could get much more exposure versus exercising in a park. The actual health effects of exercise and just residing or working near busy roadways are now starting to be understood and appear at this time to be very important.

This is not to say that people that are far removed from the hustle and bustle of downtown are necessarily breathing clean air. In fact, our air quality monitors show that unhealthy air concentrations of ozone and particle pollution are just as common in the suburban and even rural areas of our region as they are in downtown Atlanta. This is counter-intuitive, but quite true. Air pollution knows no boundaries. It isn’t just an issue for those who work in the city. It is a problem where our kids go to school and our backyards all throughout our region.

Q: What are the most common symptoms associated with smog exposure?

A: One of the most common symptoms which is under recognized and associated with ozone exposure is a feeling of chest tightness. Dry cough and breathing difficulty are some of the other frequent early symptoms. Shortness of breath is another symptom. However, patients with asthma or other chronic lung diseases who wait until they are short of breath to take action usually have to have hospital care. Therefore, I think it is far more important to pay attention to some of the more subtle symptoms. I encourage my patients to pay attention to their bodies and to take corrective action. If you start feeling any of these symptoms, slow down and take it easy.

Q: If an individual is not experiencing any symptoms could their body still be suffering damage?

A: The first problem is there is a huge difference among people with respect to recognition of symptoms, that is, there are poor perceivers and over perceivers. To appropriately treat this wide range of symptom perception is a challenge for health professionals. In the case of inhaled ground-level ozone, ozone can injure the cells that line the surface of the breathing tubes(airways) and lungs. What results is an inflammatory response to the ozone which makes a person susceptible to tissue damage. Essentially, the type of stress associated with ozone exposure is similar to the category of inflammation that results in aging of the lung. Imagine the impact of such occurrences on a runner who always runs in the heat of summer on late afternoons when ozone concentrations are at their most elevated state. In susceptible individuals, such exposure can decrease lung function in the short term. Long term studies are still assessing the impact of daily air pollution exposure over time.

Q: Is there a recovery time for a healthy individual who has been exposed?

A: That depends on several things. It depends on your capacity to form a class of chemicals called antioxidants. A chemical called glutathione made by the liver and released in the blood is pumped into the lungs at very high levels to guard against inhaled chemicals called oxidants which are found in polluted air.The concentration of glutathione is 70 times higher (in the airway) than it is in the blood and it is a major antioxidant. There are differences among people as to how much glutathione an individual produces and recovery time. For example, scientists working at Emory University have discovered that regular alcohol consumption reduces the amount of glutathione in the airway. These are the kind of subtle things that would affect susceptibility to adverse health effects of air pollution we are just now measuring in people and are beginning to learn about.

Q: What is your view on the relationship between air quality and traffic congestion?

A: Traffic congestion is the problem and I really support the way The Clean Air Campaign is trying to modify that. We have in Atlanta scientists and engineers at Georgia Tech who have performed an incredible level of speciation of the air. What this means is the precise chemical composition of the air and how it changes literally from hour to hour is now better understood. This new information supports the reason why I think air quality is linked to traffic: in the morning the levels of fine and ultra fine particles are the highest. These particles are primarily composed of organic carbon and they come from road dust and the tailpipes of vehicles. In the afternoons the speciation changes around 4 or 5 pm to sulfated aerosols, which are primarily from power plants, so the source seems to change.

Q: Do you think Atlanta is going in the right direction to improve air quality?

A: We have a lot of work to do. We’ve had an incredible influx of people in Atlanta. As a result, we’ve seen a proportional increase in the number of cars and trucks on the roads. This is everybody’s problem. It is going to take a commitment from everyone.

Q: What precautions do you recommend for children and the elderly on high alert smog days? Do you have any concerns, specifically with the obesity epidemic and with telling parents not to allow their children to play outside during high alert days?

A: If you are an overweight child, you are still probably better off exercising in smog than not exercising at all. However, you don’t have to exercise in smog. I would advise teachers, parents and school officials to be aware of the air forecast. On high ozone days, you should reschedule or change the location of outdoor activities. The point is not to discourage exercise. The point is to inform where and when people exercise to minimize exposure to air pollution.

Q: On code orange/red days do you see more patients? Do you see a correlation in your practice with a bad summer and symptoms people are having?

A: I do, but many doctors would say they do not. The reason I do and they do not is because I have a background in pediatric asthma and environmental health, pay close attention to the daily air forecast, and know the right questions to ask. Physicians need to be better prepared through medical school and residency training to better understand air pollution and environmental health issues. Most U.S. medical schools have clearly dropped the ball in this area.

Q: How do you see global warming/climate change affecting air quality?

A: One of the main things I see would be that warmth usually is associated with an increase in humidity. Warm humid conditions support an increase in indoor airborne allergens such as dust mite, mold, and cockroach. It often is important to decrease the humidity in the home to control these exposures.

Q: Can pollution that is outside cause a problem inside a home or office. Especially if located near a busy thoroughfare?

A: Most homes in this area are well insulated, so there are not a lot of air exchanges, which means that there is not a lot of ozone entering the home from outside. Now, particles present is a much different story. Particles can actually be higher in the home than outdoors at certain times. We don’t know how many of these particles are generated inside versus outside though. There can be indoor sources of pollution such as computers, formaldehyde, air fresheners, candles, etc. There is a lot of misinformation out there concerning air purifiers and air duct cleaning. Many people do not realize that electronic air purifiers clean the air by generating ozone. I would advise a person who is considering the purchase of an air purifier to check the device with a non-biased source such as Consumer Reports or websites maintained by such public health groups as the Environmental Protection Agency and the CDC. Unfortunately profit-driven motives may lead some to over promise the health benefits of their products and services.

Q: Are the air quality standards good enough now to protect public health in Atlanta? Are they stringent enough on each specific pollutant?

A: The standards are not good enough, but we are starting to focus on the right pollutants and becoming more stringent. Probably the most important shortfall is the current small particle standard, called PM 2.5. Only in the past few years have we even started to regularly measure these smaller particles. Unlike the other pollutants, the levels of PM 2.5 in many areas of the U.S. have increased in recent years. The disturbing finding is that studies conducted in several U.S. cities and in Europe have shown adverse health effects of exposure to levels of PM 2.5 significantly lower than the current standard. There is a vigorous effort now underway among air pollution experts and health experts to influence the EPA to adopt new more rigorous standards for PM 2.5 to protect the public against adverse health effects from these particles.

Q: What would you like everyone that will be reading this to know is one of the most important issues concerning air pollution and health?

A: That it is not someone else’s problem, it is our problem. If you drive a car, you are part of the problem. We need to work together and come up with common solutions to protect the public. We are all in this, and we have to continue to educate and hold ourselves and our policy makers accountable.