Wednesday 30 December 2015

Quack claims about vaping, smoking and pets

Two articles today help bring a mad year to an end with some suitably dire science. The first will ensure that thousands of people keep smoking rather than switch to e-cigarettes, thanks to a widely reported quote from the lead researcher...

"I believe they [e-cigarettes] are no better than smoking regular cigarettes." 

No such conclusion can be drawn from the study itself which looked at what happens to human cells exposed to vapour extract in a petri dish. Cell damage took place but it is unclear what this means for vapers (if anything). As the press release says...

She [the lead author] notes that cells in the lab are not completely comparable to cells within a living person. The cells lines that scientists work with have been "immortalized because of certain cell changes," she says. So it could be that e-cigarette vapor has different effects than those seen in the lab.

Also, her team didn't seek to mimic the actual dose of vapor that an e-cigarette user would get. 

Moreover, there was no attempt to compare the effect with that of smoking but there is a clear indication in study's text that cigarette smoke is far more damaging...

Treatment media was replaced every three days with 1% e-cigarette extract. Because of the high toxicity of cigarette smoke extract, cigarette-treated samples of each cell-line could only be treated for 24 hours. 
You can read an excellent critique of this research here.

Elsewhere today, the Telegraph features this 'story' on its front page...

Pets at more risk from passive smoking than humans, find scientists 

For players of bullshit bingo, this article offers up a full house. Tiny sample size? Check. Unpublished research? Check. Data-dredging? Check. Mention of 'thirdhand smoke'? Check.

There are so many gems in the article, but this stands out...

The team said pets could even be at greater risk of health problems because of their low height and more likely to inhale ‘third hand’ smoke particles which are thought to be even more carcinogenic than ‘second hand smoke.’ 

Utter wibble. Insofar as 'thirdhand smoke' exists at all (it means residual staining from indoor smoking, ie. it is not smoke), there is no evidence of any carcinogenic effect whatsoever. Since smoke rises, having a 'low height' would actually make animals less likely to inhale secondhand smoke. This being so, the researchers resort to claiming that cats are at greater risk from licking supposed toxins off their fur.

“Furthermore as pets self-groom they will ingest the smoke particles from their fur – this is a big problem for cats as they are very fastidious and thorough about their self-grooming These factors mean that pets are probably exposed to greater amounts of passive smoke.” 

It's not smoke and the study does not measure harm at all. It's difficult to tell exactly what it does measure since 'the research is still ongoing and is expected to be published next year', but the study appears to have done nothing more than measure levels of nicotine in pets' fur and make absurd extrapolations from them. The hilarious claim that 'household cats are more susceptible to cancer than dogs when living with smokers' is based on nothing more than the observation that cats lick themselves more than dogs. The study didn't look at passive smoke and it didn't look at cancer. Hold the front page!

There is the small problem - unmentioned in any of the media coverage - that scientists have conspicuously failed to induce lung cancer in animals even when exposing them to vast quantities of tobacco smoke. They finally managed it in the late 1960s by using the patently unnatural method of giving dogs tracheotomies but the failure to induce cancer by putting animals in extremely smoky environments has generally been attributed to the stubborn insistence of animals to breathe through their nose (among other factors).

Lab experiments could be - and have been - conducted to put the claims made today to the test. We don't need silly assumptions and guesswork based on nicotine concentrations.

The unpublished research (involving 79 pets) also contains a humdinger that sums up the desperate state of things as 2015 draws to a close...

...dogs living with a smoker owner gained more weight after neutering than those in a non-smoking household. 

So passive smoking causes weight gain in dogs but only if they have been castrated! Never mind that smoking itself does not cause weight gain in humans - on the contrary, it is associated with lower body weight. Never mind, too, that there is no obvious reason why having working testicles should protect dogs from this counter-intuitive effect.

The study didn't even observe weight gain in the castrated, passive smoking mutts; the claim is based on the researchers finding that 'a gene that acts as a marker of cell damage was higher in dogs living in smoking homes than those that did not.'

In sum, we have researchers claiming that tobacco smoke, which is associated with weight loss when consumed in large quantities by humans, is associated with weight gain when consumed in trace quantities by dogs. Alas, there is no word yet on how it affects the girth of cats.

Professor Knottenbelt is hoping that the findings will help smokers understand the impact they have on their pets and give them an incentive to either stop smoking full stop or restrict the habit to outside the home. 

You don't say! 

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