The smallest amount of air pollution will have a corresponding amount of health impact. There is no such thing as an exposure of air pollution that will not affect you. —Dr. Brian Moench
SALT LAKE CITY — Three new studies that underscore the link between bad air quality and significant health risks such as stroke, heart attacks and dementia suggest there is no safe level of air pollution and that more needs to be done to control the problem.
While the effects of air pollution have long been blamed for increased incidences of heart disease, the new scientific research unveiled greater risks of stroke, heart attack and cognitive degeneration — with long-term exposure to pollution said to "age" the mind by as many as two years.
Dr. Brian Moench, president of Utah Physicians For a Healthy Environment, said the studies should be a wake-up call for residents and public policy makers to get serious about the grave effects of air pollution on the everyday lives of Utahns.
"We are seeing that most of the health effects of air pollution do not have a threshold," he said. "The smallest amount of air pollution will have a corresponding amount of health impact. There is no such thing as an exposure of air pollution that will not affect you."
Two of the studies were published Monday in the Archives of Internal Medicine. Brown University's Gregory A. Wellenius, an associate professor of epidemiology, was lead author of a study that looked at 1,705 Boston-area patients hospitalized for stroke.
When controlling for other factors such as hypertension, the study found that the risk of stroke jumped 34 percent on days when traffic pollutants were classified by federal regulators as "moderate," defined as a minimal danger to health.
"These results suggest that exposure to PM2.5 levels generally considered safe by the US EPA increase the risk of (stroke onset) within hours of exposure," the study concluded. PM2.5 is fine particulate matter 2.5 micrometers or smaller.
The study looked at a hospital's admission records for stroke victims from 1999 to 2008 and cross-checked them against the exact time of the medical incident to the EPA's air quality index in the hours and days preceding each event. The increase in risk, the study found, was greatest within 12 to 14 hours of exposure to the particulate matter and strongly associated with traffic-related pollution.
Another study published in the same journal tracked nearly 20,000 U.S. women ages 71 to 80 for about a decade. It found that long-term exposure to air pollution "typically experienced by many individuals in the United States is associated with significantly worse cognitive decline in older women."
Moench said studies already have shown that the air quality along the Wasatch Front shaves two years off a person's life and this latest research demonstrates that mental acuity is at risk as well.
"We have 40 to 50 studies in our back pocket that support the conclusions," he said. "These studies are getting a lot of play, a lot of attention because they come from well known, well-respected teams."
He added that the one study's suggestion that federal air quality standards do not go far enough reinforce what the EPA's own expert committee of scientists have been arguing for years.
"The studies clearly indicate that current air quality standards do not protect health. Virtually every major medical organization in the country has been calling on the EPA to make those standards stricter."
A third study published in the Journal of the American Medical Association looked at short-term exposure to air pollution and its link to heart attacks. In that research, French scientists actually tapped the particulate information compiled in a Utah study as part of its data set.
Dr. Benjamin Horne, director of cardiovascular and genetic epidemiology at the Intermountain Heart Institute, said the journal study clearly demonstrates the increased risk of having a heart attack within a few days after a spike in air pollution — anywhere from 1 percent to 3 percent.
"It is true that the risk to any one individual is small," he said. "On the level of the whole population, having a 1 percent higher risk is dramatic. Of course, for those who are the ones actually having the heart attack, it can be devastating."
San Francisco doctor and public health official Rajiv Bhatia, in a commentary published in the Archives journal, said the findings should galvanize the medical community to argue for more protections via creative, regulatory initiatives and political support.
"He is making a not very subtle call for thousands of physicians in the community to be active in persuading policymakers to take this into account," Moench said. "He is requesting that the medical profession in general should become active in trying to shape public policy to be more protective. We agree with that concept."
All or parts of five Utah counties — Cache, Weber, Davis, Salt Lake and Utah — have been designated as "nonattainment" in meeting National Ambient Air Quality Standards set by the EPA through the Clean Air Act for PM2.5.
State air quality regulators are in the midst of crafting a plan to submit to the federal government on what actions they will take to bring those areas into compliance. The Wasatch Front's notorious inversions have led numerous advocacy groups such as Moench's to call for tighter regulations, especially as they relate to industry.
Bryce Bird, director of Utah's Division of Air Quality, said the state has been working to curtail its air quality problems. While much is left to be done, he said conditions have improved.
"Clearly, the air quality is better now than at any other time in the past," he said, noting efforts since the Clean Air Act was signed more than 40 years ago. "On the public health side, we know we are not where we need to be yet."
Dissatisfaction over the adequacy of federal air quality standards prompted a Friday lawsuit by a coalition of 11 states against EPA seeking more stringent requirements relating to PM2.5. Utah is not a part of the coalition.
A deadline for the adoption for new standards came and went last October.
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