Study: ‘No Statistical Correlation’ Between Fine Airborne Particles, Premature Death

Barbara Hollingsworth | January 7, 2014 | 4:51pm EST
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Smog hovers over Los Angeles, Calif. (AP photo)

( –  There's no evidence to support the Environmental Protection Agency’s (EPA) longstanding claim that fine airborne particulate matter measuring 2.5 micrograms or less (PM2.5) is killing thousands of Americans every year, according to the first comprehensive study of its kind.

The study, entitled “Airborne Fine Particulate Matter and Short-Term Mortality,” was released on last month. It compared air quality data collected statewide by the California Air Resources Board to 854,109 death certificates issued by the state Department of Public Health documenting 94 percent of all deaths in California between 2007 and 2010.

The study’s author, Johns Hopkins-trained biostatistician Steve Milloy, used a traditional epidemiological approach in an attempt to duplicate EPA’s findings, but found “no correlation between changes in ambient PM2.5 and mortality” from any cause of death.(See  california-pm25-experience-2007-2010-final.pdf)

“EPA says that when PM2.5 levels go up, people die every day,” Milloy told “But if PM2.5 is killing people, my data would show it, especially in Los Angeles, which has some of the worst air quality in the U.S. Not only was there no relationship there, I found a negative correlation in the LA area.”

“The lack of correlation was confirmed by examination of unusual spikes in PM2.5 and mortality. No spike examined indicated any sort of relationship to the other variable,” Milloy noted in the study.  In fact, in some cases PM2.5 levels “are trending downward, [while] deaths are trending in the opposite direction.”

“If a significant causal relationship between PM2.5 and mortality existed, that relationship should have been visible in this study. But it was not,” he concluded.

Milloy also found “no evidence” to support EPA claims that the elderly and those with heart and lung disease were “more vulnerable than the general population to the effects of PM2.5.”

The findings are at odds with EPA’s longstanding claim that breathing particles 1/30th the diameter of a human hair is deadly. Since 1997, that claim has been central to EPA’s regulation of particulate matter under the Clean Air Act, and is currently used to justify additional stringent regulations on emissions from vehicles, factories, farms, power plants and even wood-burning stoves.

“An extensive body of scientific evidence indicates that breathing in PM2.5 over the course of hours to days (short-term exposure) and months to years (long-term exposure) can cause serious public health effects that include premature death and adverse cardiovascular effects,” EPA states.

In 2011, former EPA Administrator Lisa Jackson testified before Congress that reducing particulate matter would have “an identical impact to finding a cure for cancer.” A total of 574,743 Americans died of cancer that year, according to the Centers for Disease Control and Prevention (CDC).

And in a Feb. 2012 letter to House Energy and Commerce Committee chairman Fred Upton (R-Fla.), Jackson’s successor, Gina McCarthy, then former assistant administrator in EPA’s Office of Air and Radiation, wrote that “there is no threshold level of fine particle pollution below which health risk reductions are not achieved by reduced exposure.”

Milloy told that he did the study because EPA refused to release any of the taxpayer-funded research data underlying these claims.

Steve Milloy (

“My study opened it up to questioning. Anybody can get this data and see whether there’s a relationship. If they get a different answer than I did, we can go back and see what happened,” he said. “That’s the scientific method.”

“As it stands now, only EPA-funded researchers do the work and review the work, and nobody gets to see the data. These are very expensive regulations, and the alleged benefits are entirely based on this PM/death relationship.”

Last August, the House Science, Space and Technology Committee issued its first subpoena in more than two decades, seeking what chairman Lamar Smith (R-Tex.) called “the secret science [EPA] uses as the basis for costly air regulations.” But EPA has only partially complied with the congressional subpoena, according to a committee spokesman.

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