Passive smoking – how science was defeated by the politics of public health

If you read nothing else this week, read this, or at least bookmark it for future reference.

Described as 'A look back on the 2003 BMJ controversy over passive smoking and mortality', Dogmatism, Data, and Public Health offers an insider's account of an extraordinary episode in the war on smoking.

The author, I should explain, is Geoffrey Kabat who co-authored, with James Enstrom, what is still the most significant study on the effects of environmental tobacco smoke (ETS) on non-smokers, specifically the non-smoking spouses of long-term tobacco smokers.

Twenty years ago [writes Kabat with one eye on the Covid pandemic], I found myself in the middle of a different health controversy, which seems almost quaint in retrospect. This was the question of how dangerous it is for a non-smoker to be exposed to other people’s tobacco smoke. This exposure was referred to by different names: “passive smoking,” “secondhand tobacco smoke,” and “environmental tobacco smoke.”

In contrast to a pandemic caused by a totally novel virus, conceptually, the question of passive smoking would seem to be remarkably straight-forward and susceptible to rational management and amelioration. However, because it involved tobacco and the raging “tobacco wars” of the 1970s and 1980s, what should have been a relatively simple scientific question became transmuted into a moral campaign.

Published in the British Medical Journal in May 2003, the Enstrom/Kabat study (the largest of its kind), concluded that the link between 'secondhand' smoke and coronary heart disease and lung cancer - at any level of exposure - 'may be considerably weaker than generally believed' (BBC News).

Their findings, said the authors, suggested that passive smoking could not plausibly cause a 30 per cent increased risk of coronary heart disease, as was generally believed, although a small effect could not be ruled out.

The study was widely reported, but reports focused as much on the ‘controversial’ nature of the findings as the findings themselves.

On the day the study was published, this was my entry for an online journal, or Forest diary, the precursor to this blog:

Friday May 16, 2003
To a pub in Camden for a live outside broadcast on BBC News 24. I have been asked to comment on an American study, published today by the British Medical Journal, that suggests that passive smoking has an insignificant effect on death rates from heart disease or cancer.

The study, the largest of its kind, is being trashed by the anti-smokers because it was funded partly by the tobacco industry. In fact it had originally been funded by anti-smoking money until the plug was pulled, in mysterious circumstances, in 1999, forcing the authors to find an alternative source.

Needless to say there is a strong suspicion that funding was stopped when the anti-smoking lobby saw the initial results and realised how damaging they might be to their claim that passive smoking harms non-smokers.

No-one can deny the sheer size of the database on which the study is based (118,000 adults, 35,000 of whom were never-smokers who lived with smokers), nor the fact that it has been published in a journal with a worldwide reputation and whose editor, Dr Richard Smith, resigned his previous position at Nottingham University in protest at the university's decision to accept sponsorship from British American Tobacco.

While I'm in Camden other Forest spokesmen are on Sky News and Channel 5. We have also been on BBC1's Breakfast programme, Five Live, and a host of local radio stations. Later I find myself on College Green, opposite the House of Commons, being interviewed for Carlton Television (ITV).

“This is a good day for you,” says the presenter. “You must be excited.”

“Yes,” I reply, trying hard not to sound smug. “It is and I am.”

Of course, we know what happened after that. Enstrom and Kabat continued to be targets for criticism and the science was eventually obscured by a fug of smoke and mirrors.

To their credit, neither Enstrom nor Kabat have ever allowed themselves to be bullied into silence. In 2008 Kabat even wrote Hyping Health Risks: Environmental Hazards in Daily Life and the Science of Epidemiology which was promoted as follows:

The media constantly bombard us with news of health hazards lurking in our everyday lives. But many of these alleged hazards turn out to have been greatly overblown.

The book featured four case studies - one of which was secondhand tobacco smoke.

It angers and frustrates me that the anti-smoking lobby 'won' the debate about ETS (in the sense that many people genuinely believe passive smoking to be a serious threat to health) because the evidence was, and still is, open to debate.

Twenty years on there is still no conclusive proof that environmental tobacco smoke, annoying though it may be to some people, is a significant cause of ill health, let alone thousands of deaths, among non-smokers.

Repeat a lie often enough however and eventually people will accept it, especially if they are denied all the facts, or have no interest in educating themselves.

That includes most government ministers, although I know that John Reid, Secretary of State for Health from 2003 to 2005, was not convinced that passive smoking was a serious threat to non-smokers, including bar staff, because I was one of just four or five people in the room when his senior advisor shared with his boss his own scepticism.

Ultimately none of that mattered because Tony Blair wanted to leave a legacy and Patricia Hewitt, Reid's successor as health secretary, was happy to go considerably further than her predecessor, further even than the 2005 Labour manifesto.

Not for the first time the politics of public health defeated the science and it could happen again.

Despite the largest study of its kind providing very little evidence that exposure to tobacco smoke indoors is a serious threat to non-smokers, there was an attempt only last week to ban on smoking outside pubs.

Speaking in the House of Lords, one Lib Dem peer declared:

The public health case for this policy is extremely clear; there is no risk-free level of exposure to second-hand smoke ... The smoking ban of 2007 protected workers from indoor exposure to tobacco smoke ... It is time we took action to protect them from outdoor exposure as well.

See 'Inside out'.

I am delighted then that Geoffrey Kabat has returned to the fray, if only to remind us of his 2003 study which must never be forgotten. Likewise his co-author, James Enstrom, who has posted his own comment in response to Kabat's thoughtful essay:

I commend Geoffrey Kabat on his excellent 20-year perspective on our May 17, 2003 BMJ article. My own 4-year perspective was published in my October 10, 2007 Epidemiologic Perspectives & Innovations article “Defending legitimate epidemiologic research: combating Lysenko pseudoscience” (DOI: 10.1186/1742-5573-4-11).

Our BMJ article and the reaction to it have revealed several serious problems with epidemiology. The problems that I want to highlight are described in my July 8 talk “Corruption of Science by the American Cancer Society”. Further details of this corruption are provided in my unanswered August 7 email letter to top ACS officials and scientists and in Geoffrey’s email letter to these same ACS officials and scientists. I welcome comments from any reader who is concerned about the epidemiologic problems raised by Geoffrey and me.

Further reading: The Smoking Issue by Joe Jackson with a foreword by Lord Harris of High Cross (Forest, 2004); Prejudice & Propaganda: The truth about passive smoking (Forest, 2005).

Comments

[Rose2]

Simon, thank you for the link to Kabat's essay, I hadn't seen that.

I remember the following furore vividly though.

Passive smoking doesn't cause cancer - official
1998

"THE world's leading health organisation has withheld from publication a study which shows that not only might there be no link between passive smoking and lung cancer but that it could even have a protective effect.

The astounding results are set to throw wide open the debate on passive smoking health risks. The World Health Organisation, which commissioned the 12-centre, seven-country European study has failed to make the findings public, and has instead produced only a summary of the results in an internal report."

The findings are certain to be an embarrassment to the WHO, which has spent years and vast sums on anti-smoking and anti-tobacco campaigns. The study is one of the largest ever to look at the link between passive smoking - or environmental tobacco smoke (ETS) - and lung cancer, and had been eagerly awaited by medical experts and campaigning groups."

"The results are consistent with their being no additional risk for a person living or working with a smoker and could be consistent with passive smoke having a protective effect against lung cancer. The summary, seen by The Telegraph, also states: "There was no association between lung cancer risk and ETS exposure during childhood."
http://web.archive.org/web/20021128202555/http://www.telegraph.co.uk/htmlContent.jhtml?html=/archive/1998/03/08/wtob08.html

Warning: the health police can seriously addle your brain
18 May 2003

"It was a rare good news story in an otherwise grim week. A landmark study into the effects of inhaling other people's smoke revealed that fears that passive smoking kills more than 1,000 a year in the UK alone are unfounded."

"The demise of a supposed major risk to public health might be expected to prompt celebration among medical experts and campaigners. Instead, they scrambled to condemn the study, its authors, its conclusions, and the journal that published them. The reaction came as no surprise to those who have tried to uncover the facts about passive smoking. More than any other health debate, the question of whether smokers kill others as well as themselves is engulfed in a smog of political correctness and dubious science.

Researchers who dissent from the party line face character assassination and the termination of grants."
https://www.telegraph.co.uk/news/uknews/1430438/Warning-the-health-police-can-seriously-addle-your-brain.html

[Rose2]

Twenty years later I was disturbed to read

The public isn’t being told the full truth about the climate threat
8 September 2023

"Patrick Brown, the co-director of climate and energy at the Breakthrough Institute in California, has blown the whistle on an open secret about climate science: it’s biased in favour of alarmism."

“It is standard practice to calculate impacts for scary hypothetical future warming scenarios that strain credibility,” wrote Brown. So, after learning this lesson the hard way when his nuanced papers were rejected, he adapted his latest to suit their apparent prejudices – and it was published.
Nature’s editor, Magdalena Skipper, responded by trying to shoot the messenger, criticising Brown’s deception as “poor research practices”.

"We have known for years that distinguished scientists who think that global warming is a problem but not a “crisis” get ostracised, cancelled or rejected by peer reviewers. Meanwhile, even the most trivial study that comes to an alarmist conclusion – such as a notorious one that found fish behaviour to be affected by carbon dioxide – gets rushed into print and celebrated in the media."
https://www.telegraph.co.uk/news/2023/09/08/the-public-isnt-being-told-the-full-truth-about-the-climate/

Climate scientist admits overhyping impact of global warming on wildfires to get published

"But in a blog and series of posts on X, formerly known as Twitter, Dr Brown admitted that there were other factors influencing wildfires that he had purposefully omitted – such as poor forestry management and an increase in people starting fires deliberately or accidentally."
https://www.telegraph.co.uk/news/2023/09/06/global-warming-climate-change-scientist-unrealistic-nature/

Deja vu