Smoke fails to clear

I'll take this opportunity to return to a subject which is still causing controversy. On another website I'm told by a scornful but anonymous person that, by turning to the Wikipedia entry on second-hand smoke, I can see that the question of the danger from such smoke is resolved. I have a higher opinion of Wikipedia than many, but I think we all acknowledge that, where the subject under discussion is controversial, it can let you down.
Entries have often been captured by one side or the other in the controversy, and you have to be alive to the possibility that you may be missing something.

So what about the study by Enstrom and Kabat, which my excerpt from Christopher Booker mentions in my earlier posting?  I've looked for some sources on this which wouldn't necessarily be on my side, or which may be unfamiliar.

As Sarah Boseley wrote in her Guardian account of the report (16th May 2003, page one): 'The study is given scientific credibility by its publication in one of the world's most prestigious peer-reviewed journals, whose editor Richard Smith quit a professorship after Newcastle University accepted £3.8m of funding from British American Tobacco.'

There's been a lot of anger about this study, as there often is when science comes into conflict with intellectual fashion, and no doubt we'll have people commenting here about 'vast majorities' and 'deniers'. The use of such terms is always a sign that the scientific method has been abandoned, and other forces are in play. Scientific truth is not established by majority vote, opinion poll or current fashion. That would reduce it to the level of 'Britain's Got Talent', or, worse, a British general election. Scientists don't 'deny'. They prove or fail to prove, or disprove. Or they provide evidence which upsets the theories of others, and which those others must other accept or disprove.

It's said that Enstrom and Kabat (both non-smokers) took funding from Big Tobacco. This is undoubtedly true, and in my view a great pity because it draws attention away form more important aspects of the research,  but as far as I can see they took this cash only after they had lost if from elsewhere.  What were they supposed to do? Fail to complete the research at all, because they were so pure? And the question is , did this funding influence the outcome, or is this just an ad hominem attack on the individuals involved?

Can anyone point to anything in the research, which was after all a unique and long-lasting survey, now unrepeatable, which was influenced by Big Tobacco? Please do so.

And are there are any other reasons to believe that the evidence for the rebuttals of Enstrom and Kabat, or for the claims of second hand smoke's dangers, is thin? I think there may be.

It's said, for instance, that the people in Enstrom and Kabat's survey (the non-smoking spouses of smokers) would have encountered second-hand smoke apart from in their homes, almost everywhere in this period. This may well be so, but surely if they had encountered it *as well* day and night, in their own homes, and if it os as deadly as claimed, they would have been at significantly greater risk anyway.

Trawling through some US newspapers, I found this interesting reflection in an article in the Chicago Sun Times (22nd October 2005), by Dennis Constant( Director of the Illinois Taxpayer Education Foundation): 'According to Michael Fumento, writing in Health Care News, in 2003 professors James Enstrom of UCLA and Geoffrey Kabat of the State University of New York reported in the British Medical Journal that their 39-year study of 35,561 Californians who had never smoked showed no causal relationship between exposure to environmental tobacco smoke and tobacco-related mortality.

'Fumento also reports that in 1999, an Environmental Health Perspectives survey of 17 studies of environmental tobacco smoke and heart disease found only five that were statistically significantly positive. And in 2002, an analysis of 48 studies of environmental tobacco smoke found only 10 studies that were significantly positive, one that was significantly negative, and 37 that were not significant in either direction.

'Fumento adds that in 1975, when many more individuals smoked in restaurants, cocktail lounges and transportation lounges, the concentration of tobacco smoke then was equivalent to 0.004 cigarettes an hour -- a very small amount.

'Despite the claim of anti-smoking groups that scientific studies unanimously have shown that second-hand smoke is killing thousands from lung cancer, the truth is that the vast majority of such studies failed to find any statistically significant link.'

The article also refers to: '...the 1993 study by Michael Siegel, "Involuntary Smoking in the Restaurant Workplace," published in the Journal of the American Medical Association, which declared that non-smoking restaurant workers have a 50 per cent higher risk of lung cancer than the general population. However, a peer review of the study completed in 2000, authored by Martha Perske, revealed that the claimed 50 percent increased risk was based on six studies that had absolutely nothing to do with second-hand smoke in restaurants, bars, or anywhere else.

Small increased risks for lung cancer were found in food service workers, but there was no evidence in any of the six studies that food service workers had been exposed to tobacco smoke!'

A report in Newsday (16th May 2003) summed up the controversy quite neatly: 'Kabat and co-author James Enstrom of UCLA found no clear risk pattern for either disease among the 35,561 people who had never smoked, but whose spouses did.

'Critics charged yesterday that the study's funding by a consortium of three tobacco firms calls its objectivity into question.

'"For this study, you have to consider the source," said Marianne Zacharia, director of education and advocacy for the American Lung Association of Nassau-Suffolk. She noted that existing data collected by state, federal and international agencies have all documented a link between second-hand smoke and an increased risk for both diseases.

'Kabat defended the study's methods and instead questioned the validity of past research, charging that much of the controversy has derived from difficulties in measuring smoke intake by non-smokers.

'"Why is the science weak?" he said. "Because environmental smoke is a lot more dilute than what people are sucking into their lungs, and it stands to reason that you would not see as great a risk."'

That last paragraph does seem to me to make a good point.

Let me stress that I have no dog in this fight. I don't smoke, I dislike people smoking near me,  I don't take money from the tobacco companies and - crucially - I actively support the current moves to put as many restrictions on tobacco as can reasonably be imposed. I back the banning of smoking in restaurants, public transport, pubs and so forth.

So it simply cannot be said that I am believing this stuff because I have an interest in doing so. Yet my remark, that the evidence for the dangers of passive smoking was rather thin, has provoked rage and talk of denial' here and elsewhere.

Why would I 'deny' it? Why would Enstrom and Kabat do so? In my case because I am, simply, unconvinced. Am I not entitled to be?