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Smoking in cars: BMA admits "error"

Fri 18th November, 2011

The British Medical Association has admitted that its claim that smoking in cars generates 23 times more toxins than you would find in a smoky bar is wrong.

The claim was made in a press release issued on Wednesday. Last night the BMA issued a statement:

"Further studies demonstrate that the concentration of toxins in a smoke-filled vehicle could be up to 11 times greater than that of a smoky bar. We apologise for this error."

Online commentators have been quick to criticise the BMA and question even this claim:

Writing for the Telegraph website, Brendan O'Neil, editor of the online magazine spiked, commented:

"Can it really be the case that having a ciggie in a car exposes passengers to a climate 11 times nastier than you would find in a bar packed with people puffing on fags? Even one of the studies cited by the BMA as proof for this figure actually says something quite different. Published in the American Journal for Preventative Medicine, the study found that in a car with closed windows, smoking generated particulate concentrations of 272 micrograms per cubic metre of air, while in a car with its windows open smoking gave rise to just 51 micrograms per cubic metre. In bars, the figure was either similar (the study found 206 micrograms per cubic metre in smoky bars in Massachusetts) or it was significantly higher (reaching 412 micrograms per cubic metre in smoky bars in New York). Nowhere can I see hard evidence that smoking in cars generates 11 times the toxicity of a smoky bar."

Chris Snowdon, author of Velvet Glove, Iron Fist: A History of Anti-Smoking, commented:

"Aside from removing the now-notoriously fictitious "23 times" claim, it is significant that the BMA has removed all reference to "realistic conditions". As I have said before, when experiments have been conducted in realistic conditions (ie with one or more windows at least partially open), the amount of secondhand smoke in a moving vehicle is much lower than in a smoky bar. When all windows are closed and the ventilation is turned off, however, concentrations are higher than in a smoky bar. Of course they are. Cars are smaller than bars. That's why people who smoke in a car open the window."

Welcoming the BMA's "half correction", Snowdon added:

"I wonder if they will use their formidable PR machine to make sure the media get the message? (Rhetorical question). The fact remains that millions of people have now been informed that secondhand smoke in a car under realistic conditions "is 23 times" more concentrated than secondhand smoke in a bar. Now, with the world's media having moved on, the BMA has little to lose by quietly announcing that what they meant to say was that secondhand smoke in a car under unrealistic conditions "could be up to 11 times" more concentrated than secondhand smoke in a smoky bar."

Sources: Telegraph Blogs (18 November 2011),

Velvet Glove Iron Fist (17 November 2011) c

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