Passive smoke signals

“Secondhand smoke debate over.” That’s the message from the Surgeon General’s office, delivered by a sycophantic media. The claim is that the science has now overwhelmingly proved that smoke from others’ cigarettes can kill you. Actually, “debate over” simply means: “If you have your doubts, shut up.”

But you definitely should have doubts over the new Surgeon General’s report, a massive 727-page doorstop. Like many massive reports on controversial issues, it’s probably designed that way so nobody (especially reporters on deadline) will want to or have time to read beyond the executive summary. That includes me; if I had that much time I’d reread War and Peace. Twice. But the report admits it contains no new science so we can evaluate it based on research already available.

First consider the 1993 EPA study that began the passive smoking crusade. It declared such smoke a carcinogen based on a combined analysis (meta-analysis) of 11 mostly tiny studies. The media quickly fell into line, with headlines blaring: “Passive Smoking Kills Thousands” and editorials demanding: “Ban Hazardous Smoking; Report Shows It’s a Killer.”

But the EPA’s report had more holes than a spaghetti strainer. Its greatest weakness was the agency’s refusal to use the gold standard in epidemiology, the 95 percent confidence interval. This simply means there are only five chances in 100 that the conclusion came about just by chance, even if the study itself was done correctly.

Curiously, the EPA decided to use a 90 percent level, effectively doubling the likelihood of getting its result by sheer luck of the draw.

Why would it do such a strange thing? You guessed it. Its results weren’t significant at the 95 percent level. Essentially, it moved the goal posts back because the football had fallen short. In scientific terminology this is know as “dishonesty.”

Two much larger meta-analyses have appeared since the EPA’s. One was conducted on behalf of the World Health Organization and covered seven countries over seven years. Published in 1998, it actually showed a statistically significant reduced risk for children of smokers, though we can assume that was a fluke. But it also showed no increase for spouses and co-workers of smokers.

The second meta-analysis, published in the British Medical Journal (BMJ) in 2002, likewise found a statistical significance when 48 studies were combined. Looked at separately, though, only seven showed significant excesses of lung cancer. Thus 41 did not.

Meta-analysis, though, suffers from such problems as different studies having been conducted in different ways — the apples and oranges conundrum. What was really needed was one study involving a huge number of participants over a long period of time using the same evaluation.

We got that in the prestigious British Medical Journal in 2003. Research professor James Enstrom of UCLA and professor Geoffrey Kabat of the State University of New York, Stony Brook presented results of a 39-year study of 35,561 Californians, which dwarfed in size everything that came before. It found no “causal relationship between exposure to [passive smoke] and tobacco-related mortality,” adding, however “a small effect” can’t be ruled out.

The reason active tobacco smoking could be such a terrible killer while passive smoke may cause no deaths lies in the dictum “the dose makes the poison.” We are constantly bombarded by carcinogens, but in tiny amounts the body usually easily fends them off.

A New England Journal of Medicine study found that even back in 1975 — when having smoke obnoxiously puffed into your face was ubiquitous in restaurants, cocktail lounges and transportation lounges — the concentration was equal to merely 0.004 cigarettes an hour. That’s not quite the same as smoking two packs a day, is it?

But none of this has the least impact on the various federal, state and city agencies and organizations like the American Lung Association for a very good reason. They already know they’re scientifically wrong. The purpose of the passive smoking campaign has never been to protect non-smokers, but rather to cow smokers into giving up the habit.

It’s easy to agree with the ultimate goal, but inventing scientific outcomes and shutting down scientific debate as a means is as intolerable as it was when Nazi Germany “proved” the validity of eugenics.

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