LOIS HENRY: Air board and facts have iffy relationshipThe Bakersfield Californian | Saturday, May 29 2010 01:00 PM
Last Updated Saturday, May 29 2010 01:00 PM
If you discovered that the facts upon which you based a certain action were no longer true, you'd probably change your actions to fit the facts.
For example, if you lost your job, you probably wouldn't buy a new car since your income had dropped.
At least that's the logic we peons typically operate under.
Not the California Air Resources Board.
Facts don't fit? No prob -- they just ignore, obfuscate or, when all else fails, change the rules.
That appears to be the case regarding preliminary results of a study commissioned by CARB to look at the health effects on Californians of PM2.5 (tiny particulate matter from exhaust, smoke and dust). These were presented at a symposium held February 26.
The results show a big, fat zero.
As in, there is no evidence of "excess mortality associated with PM2.5" for deaths from "all causes" in California.
This is important because PM2.5 is the new bugaboo in the world of air pollution.
The supposed ill effects of PM2.5 on public health are the foundation for a host of existing and upcoming regulations, some of which are looming over the trucking and heavy equipment industries like an anvil.
We've been told over and over that the science on PM2.5 is solid, overwhelming and final. I've contended since early last year that's not entirely true.
In fact, if the early results from this latest study hold true, it will join at least four other significant studies that show no elevated risk of premature death due to PM2.5 exposure, particularly in California, where we don't have the levels of sulfates that regions in the eastern United States do.
Side note pitstop: This does not mean I think our air is pristine or that it's just dandy to go suck on a tailpipe. We should work to clean our air as much as possible, of course. But regulations should be based on sound science and done in a way that doesn't entirely wreck our already critical economy.
OK, back to the topic at hand.
John Balmes, a CARB board member, acknowledged that some studies do show that the further west you go, the lower the risk of death from PM2.5. And there has been a data gap on the effects in California.
"Yes, we use different fuels, have cleaner engines and retrofitting, but diesel PM is still diesel PM and I find it hard to believe diesel PM is different here than on the East Coast," Balmes said.
Any California anomalies likely won't matter anyway, he said, as the federal Environmental Protection Agency is moving forward with a stricter standard for PM2.5 that all states will have to meet.
"And we can't clean up the air in California without controlling diesel emissions," he said.
Wait a minute, does that mean it suddenly doesn't matter if this stuff is killing people? Why bother with the study then?
I spoke with Michael Jerrett, the lead scientist on the CARB-funded study, about his results showing no premature deaths in California due to PM2.5 exposure. He cautioned that first, these are preliminary results and second, even if the results hold, you can't use just one study to determine what regulations are needed to protect public health.
Again, he said, the body of evidence supports the contention that PM2.5 is dangerous, particularly in regard to cardiovascular disease-related deaths.
As far as his study, it's the link between PM2.5 and cancer are negative and that is what brings the "all cause" category down to zero.
Still, you can't ignore the possible links between air pollution and the other causes of death, especially cardiovascular, he insisted.
OK, except CARB bases its regulations on "all causes" of death, also called "premature deaths."
They do that because, as Jerrett acknowledged, it's too difficult to say whether a cardiovascular-related death is strictly associated with air pollution.
Even so, CARB may abandon the "all causes" approach, he said.
Ah, yes, if the facts don't fit, change the rules.
To be fair, Jerrett did point out that some small control studies have shown a plausible connection between air pollution and diminished lung function. To be sure, air pollution isn't good for us.
But CARB's typical approach is to take a bunch of epidemiological studies -- routinely discounting those that show no elevated risk of premature death from PM2.5 exposure -- average the results and -- BLAMO -- come up with ludicrous assertions that exposure to PM2.5 can be associated with 18,000 deaths a year in California. That was the number tossed out in their most recent health effects report by Hien Tran, who was discovered to have lied about his academic credentials.
I wondered, given his results so far, if Jerrett felt these studies and how they're being used are a bit alarmist.
"I don't think so," he said. "There are hundreds of studies pointing, for the most part, in the same direction."
Other scientists at that February 26 symposium had very different views.
Frederick Lipfert, a doctor of environmental studies who has published reams of papers, studies and books on human mortality and air pollution, even scolded Jerrett for saying he intended to rework his data to find out why he had a negative result for PM2.5 and cancer deaths.
"When you got a negative result, you said you wanted to find out what was wrong, but you didn't say the same thing for your positive results," he said. "That's something I find inappropriate."
Suresh Moolgavkar, a noted epidemiologist and professor at University of Washington, reminded the other scientists that results are easily biased in these massive epidemiological studies.
"If you start with the assumption that PM is killing people, that is what you will find," he said.
And when the facts don't fit that mold, toss out the mold.
Opinions expressed in this column are those of Lois Henry, not The Bakersfield Californian. Her column appears Wednesdays and Sundays. Comment at people.bakersfield.com/home/Blog/noholdsbarred, call her at 395-7373 or e-mail email@example.com