By Steven Milloy
Copyright 2000 Fox News
August 4, 2000, FoxNews.com

One of the most controversial “junk science” issues of recent years — whether air pollution causes premature death — will remain controversial for the foreseeable future despite activist claims and media headlines.

“Independent Institute Finds Key Pollution Studies Are “Sound Science,” blared a recent press release from the American Lung Association. “It shows once again that air pollution shortens lives, and strong [Environmental Protection Agency] standards are needed to protect public health,” stated the ALA.

The reality is somewhat different — at least according to Health Effects Institute, the organization whose work is being cited.

The saga starts in November 1996 when the EPA proposed more stringent regulation of airborne particulate matter (soot). The EPA initially claimed further regulation would prevent 20,000 “premature deaths” every year at an annual cost of $8 billion. By valuing each life saved at about $5 million, the EPA estimated the monetized benefits of saving these lives at $100 billion per year.

But the validity of the EPA’s estimates was questioned. In particular, the estimate of premature deaths was based on a single study — called the “Pope study,” after its lead researcher C. Arden Pope of Brigham Young University. The Pope study reported that airborne particulates were associated with a 17 percent increase in premature deaths. But this result constituted only a weak statistical correlation — not scientific proof of a cause-and-effect relationship between air particulate pollution and premature death.

Although the study included more than 550,000 people, the researchers did not measure how much air pollution even one study subject was exposed to. Instead, they guessed how much pollution these individuals might have encountered.

Study subjects undoubtedly differed in many behavioral, occupational, environmental and genetic factors that probably were not adequately considered by the researchers. Any one of these factors, or a combination thereof, could explain the reported correlation.

For example, the researchers did not look at the subjects' diets, income, health histories, genetic predispositions to illness, exercise habits and social habits — all well-established risk factors for premature death. The researchers did adjust for some factors — including smoking habits, education level and occupational exposures — but additional adjustments could easily negate the purported 17 percent increase in risk.

A further problem was that no one has ever demonstrated how typical levels of airborne particulates could cause premature death.

In this context, the reported correlation could easily have been a statistical artifact. As the National Cancer Institute earlier pointed out: “In epidemiologic research, [risks of less than 100%] are considered small and usually difficult to interpret. Such increases may be due to chance, statistical bias or effects of confounding factors that are sometimes not evident.”

But the EPA did not back down — even when an elementary statistical error in the EPA’s calculations was discovered that knocked down the lives-saved estimated to 15,000 and some economists estimated the proposal’s cost to exceed $100 billion annually.

The controversy prompted Congress to ask the EPA to produce the Pope study’s raw data so independent scientists could check the study’s results.

The EPA initially balked, saying there was no purpose in any re-analysis of the EPA-funded study. Finally, after the EPA issued the regulations, access to the Pope study data was given to the Health Effects Institute, a Massachusetts-based research organization funded by the EPA and auto industry.

HEI issued its report last week — three years after the regulations were finalized. The results are not quite as the ALA press release touts.

Using essentially the identical methodology as the Pope study researchers, HEI produced virtually the same results — hardly a surprise. A naive media reported this “replication” in headlines such as “Research on air particles passes muster” and “Studies back particulates’ link to death.”

But the re-analysis ha essentially the same shortcomings as the original study. The researchers did not factor in to their analysis the effect of diet or genetics on death rates. Data on exercise habits were factored in and reduced risk estimates by almost 30 percent. But the quality of the data on exercise is debatable; incredibly, it indicates no difference in death rates between non-exercising study subjects and heavy-exercising study subjects. Better quality exercise data could have a more dramatic effect.

There is a similar data quality problem with health history. The re-analysis paradoxically indicates that healthy study subjects had twice the risk of premature death of diseased study subjects.

Neither of these data problems is surprising given how the study data were collected. The American Cancer Society amassed the data by having 70,000 volunteers — not trained data collection specialists — go to their friends, family and neighbors and ask personal, health-related questions. No effort was made to verify or validate the study subjects’ responses.

It’s no wonder the HEI concluded its report: “It is important to bear in mind that the results of our reanalysis alone are insufficient to identify a causal relation with mortality.”

So why did the ALA jump to its conclusion? That question perplexed HEI’s president Daniel Greenbaum who noted the ALA issued a press release last April titled “New Health Research 'Vindicates' EPA; Soot Particles Are Deadly, Lung Association Notes ” — three months before the HEI report was made available to the public.

The explanation, though, lies with the finances and politics of the ALA. As first reported by Investors Business Daily in January 1997, “The ALA has had a long — and lucrative — relationship with the EPA.” In the years before the EPA air pollution proposal, the agency gave the ALA almost $5 million — despite the ALA suing the EPA almost every year claiming the agency wasn’t complying with the nation’s air pollution laws.

“If you think the EPA is upset with the ALA suing them, think again,” said Scott Segal, a Washington, DC-based attorney. “Truth be known, the EPA wants to be sued, because every time they are sued it expands the reach of the Clean Air Act.”

Unfortunately for the ALA and the EPA, another lawsuit has pre-empted the claimed “vindication” of the Pope study. A federal appellate court overturned the EPA regulations in May 1999 on a number of grounds. The case is pending before the Supreme Court.

No doubt more research will continue into the potential health effects of air pollution. But another by-product of the Pope study controversy may change the shape of the next scientific debate.

Because of difficulty in obtaining the Pope study data, a federal law was enacted in October 1998 requiring that federally funded scientific data used to support federal policy must be publicly available through the Freedom of Information Act.

With any luck, the next debate over the potential health effects of air pollution won’t be hampered by EPA’s “secret science.”

Steven Milloy is a biostatistician, lawyer, adjunct scholar at the Cato Institute and publisher of JunkScience.com.