Effect Measure

Second hand smoke is bad for you

A week ago we defended a colleague against attacks from overzealous anti-smoking crusaders when he criticized their patently absurd claim that breathing 30 minutes of second hand smoke in a public place was equivalent heart attack risk to that of a smoker. Some interpreted this as our saying second hand smoke was not as bad as alleged. I suppose the question here is “alleged by whom,” but we don’t have to play those games. Second hand smoke is bad for the health of those exposed to it for any length of time, as a new study shows graphically — literally:

It’s not a smoking gun, but it’s smoking-related, and it’s there in bright medical images: evidence of microscopic structural damage deep in the lungs, caused by secondhand cigarette smoke. For the first time, researchers have identified lung injury to nonsmokers that was long suspected, but not previously detectable with medical imaging tools.


The researchers studied 60 adults between ages 41 and 79, 45 of whom had never smoked. The 45 non-smokers were divided into groups with low and high exposure to secondhand smoke; the high-exposure subjects had lived with a smoker for at least 10 years, often during childhood. The 15 current or former smokers formed a positive control group.

The research team prepared an isotope of helium called helium-3 by polarizing it to make it more visible in the MRI. Researchers diluted the helium in nitrogen and had research subjects inhale the mixture. Unlike ordinary MRIs, this MRI machine measured diffusion, the movement of helium atoms, over 1.5 seconds. The helium atoms moved a greater distance than in the lungs of normal subjects, indicating the presence of holes and expanded spaces within the alveoli, tiny sacs within the lungs. (Sciencedaily)


Figure: On the left (a) low exposure to second hand smoke, (b) high exposure to second hand smoke, (c) smoker or former smoker. Red areas generally normal, yellow areas abnormal. (Credit: Children’s Hospital of Philadelphia and the University of Virginia, via Sciencedaily)

Using this ingenious method, a third of non-smokers with prolonged exposure to second-hand smoke showed the kinds of structural changes typical of smokers, interpreted as a mild form of emphysema. Two-thirds of high exposure non-smokers also had reduced diffusion, possibly a sign of chronic bronchitis. Either way, exposure to second hand smoke has an effect and the effect doesn’t appear to be benign or inconsequential.

What this means exactly will take time to sort out. But it doesn’t let second hand smoke off the hook. On the contrary.


  1. #1 Stuart Coleman
    November 27, 2007

    The question isn’t whether large exposure to second-hand smoke is bad, it’s quite obvious that if you’re breathing it in day after day you’re going to be just like a light smoker. The question is if the people who scream about needing total smoking bans because the 15 seconds of second-hand smoke I get while sitting outside the airport with a smoker downwind are going to kill me. That’s the part that’s false and misleading, and the anti-smoking advocates don’t make that distinction.

  2. #2 Sara
    November 27, 2007

    What about the people whose lungs have already been damaged? That exposure can be pretty uncomfortable.

    I did not smoke but grew up in a house with 2 heavy smokers. Now I have severe asthma and I begin to cough whenever I am exposed to any kind of smoke: cigarette, cigar or fireplace. My asthma doc says any exposure to smoke is bad for me.

    For what its worth I usually try to move away from smokers, especially if they are outside. Most smokers also realize I am not just expressing social disappoval, I am getting an asthma attack.

    I am hyper-reactive; most people would not have this reaction to brief exposures to smoke–but we do exist.

  3. #3 Paul
    November 27, 2007

    What should be the greatest concern here is the exposure of workers to second hand smoke in their workplace. Smoking in any workplace should be banned, with no exceptions.

  4. #4 birdflubreakingnews
    November 27, 2007

    Well you may be surpised to hear the views of Madam Supari,the Indonesian Health Minister, in a Q & A session, on Smoking and er.. other things including the Best Breakfast for women:)

    Here is the link:

  5. #5 Cathie
    November 28, 2007

    My situation was rare, but brief exposures to second-hand smoke several times nearly killed me when I was in grad school.

    Sphenoid sinusitis can rapidly progress to bacterial meningitis – and MD’s rarely diagnose it except at autopsy. My fellow students thought I was silly to declare my office non-smoking, so they secretly smoked in it when I wasn’t there. I would instantaneously develop congestion, then be down and out with sphenoid sinusitis and fever spikes to 103 for a week. After I recovered, they’d have another smoking party in my office and I would spend another week in total agony — and I am a tough stoical soccer player. All the while, my physicians were baffled. Finally I demanded an MRI and was rushed into a very high-risk emergency surgery (high % of lobotomy and fatal nicked internal carotid).

    Rare? Yes. But I am probably not the only case of smoke-induced acute sphenoiditis.

    Did the smokers ever express any concern when they learned they had nearly killed me? Nope. They said their right to smoke necessitated protection — they were being valient citizens in protecting the rights of smokers — my health problem was a personal weakness that should not restrict smokers rights. Logic does not exist in an addiction!

  6. #6 Frank Mirer
    November 28, 2007

    An important scientific observation from the environmental tobacco smoke literature is the persistence of the carcinogenic effect over a wide range of doses. We can imagine that one pack a day is equivalent to an occupational exposure level of 20 mg/M3 TWA [10 mg/marlboro x 20 cigs /10 M3 breathed per day at work,].

    [This is about 1/10 the exposure level needed for a meaningful tumor yield in a laboratory bioassay in rats.]

    ETS levels associated with increased lung cancer risk [relative to non-smokers] are likely in the range of 20 ug/M3 [ok, I picked 20 to make division easier.]

    So, the risk presists over a 1000-fold range.

  7. #7 Ann P
    November 30, 2007

    The key words in the Science Daily article were about “high exposure” to secondhand smoke and those “heavily exposed”.

    This is the distinction that Michael Siegal makes in his blog….Siegal does not disagree with the facts and evidence about chronic or prolonged exposure to secondhand smoke. His point is about not misrepresenting the scientific evidence about brief exposure.

  8. #8 Analytical
    October 26, 2009

    Just tell the people in your family quit smoking.

  9. #9 Pat Mejias
    October 26, 2011

    I was the only non smoker out of 5 siblings. My parents were also very heavy smokers. My mom died at 64, my dad at 72 and my brother at 55. My sis had a heart attack at 46. She is now 60, looks older enough to be my mom and still a 3 pack a day smoker. My younger sister’s grandchildren do not visit because their mom doesn’t want them in the apartment of a smoker. My sister cannot understand that even though she’ll smoke outside the apartment when the kids are there, the smoke is still in the house. I am at a point where I do not visit them because of this. When I go out to a bar with one of my sisters, she’s outside smoking most of the time and it’s not even worth going out with her. I have bad asthma now and my doctor says my lungs look like I have been smoking for 20 years. I get so angry that I have never toched a cigarette and I am sick because of it! My sisters don’t understand why I don’t visit them.

  10. #10 SickOfYourSmoke
    November 11, 2011

    Why am I not allowed to take dump out in public, but a neighbor and smoke like chimney and fill MY house with his or her toxic output?

    Why do I need a complete 100% proven link type of study to show that their output is affecting my life?

    Why am I intolerant because I don’t want to live the bottom-of-the-barrel lifestyle in a fog because of the smoke of my neighbor?

    Why must _I_ move? Why doesn’t the scumbag have to move?

    The average smoker makes 1/5th of my income, you know, like Joe the Plummer ($20-40K a year income, 0 in taxes, $10-20K in cigs and beer), why do I have to change my life to accommodate their inconsiderate druggy lifestyles?

    Do your crack, your heroine, cocaine, pot, spray paint, car exhaust, alcohol, whatever (it all should be legal), I don’t really care what you do to YOURSELF, but when you put in MY face, it should be considered an assault and I should be able to react in whatever way I feel I need to, to stop your assault.

    I have had the misfortune of having inconsiderate drug addicted smokers flock around me in the last couple years, I can’t seem to get away from them. I make well over $100K a year and no matter what I pay for rent, I can’t get away from this scum in society. I will not buy a house these days as I am afraid of what I will do in revenge in I continue to experience this misfortune.

    The drug addictions of the scum and self-absorbed, inconsiderate in society should not become my daily problem, or anyone else’s problem. If you want to smoke, go off and live in the woods and isolate yourself as you should be – nature will take its course. Just because you chose a Jesus-Right-Wing drug does not mean that you should have special privileges, you are still scum because of your behavior in the face of others. It is one thing for you to be annoying (that is your right) but when you affect my health, I should be able to affect yours.

    Look at an intersection anywhere in the US. Look what the whole world would be like if smokers had their untethered ways – 100% pure inconsiderate, self-absorbed, scum. It is a trashy mindset, it is not a weakness, bla, bla, bla, it is the scum gene. It should be culled from the genepool.

    Try to do your part. If you smoke, please do not reproduce. Not only will your kids suffer (in half the cases) but in the other half (the ones who’s nervous systems are in a retarded state to start with), they just carry on the stupid gene, extending the problem that much longer with the species. And you will cost me a fortune, because most of you think you are healthy and you won’t pay for insurance (and rarely have jobs that provide it) I will have to pay for you, again and again. You are the worst kind of socialist, the one who can’t admit that they are a socialist.

    So what if you grandmother lived to 98 and smoked everyday, why must I become your living experiment? She probably had a low expectation in life, like you, and achieved it, too dumb from the fog to ever notice much.

    It is really bad that we got away from the gene-pool cleansing system of agricultural accidents, 100+ years ago. Socialism (from the right) has screwed up the species, possibly forever.

    Smoking is up 20% in the last 3 years, easily measurable, not really disputable except by the anti-science crowd – seemingly growing in size lately. We are headed in a bad direction.

    We really are doomed as a species, the dumb are given too many chances to keep getting wrong, all while reproducing like mad.

  11. #11 Mary
    January 17, 2012

    I quit smoking ten years ago. I figured a brain tumor non related to smoking was enough and I wasn’t going to take that big of a gamble. I’m so glad I quit and will never go back to it.
    My husband is in the process of quitting now. It’s gotten to the point where I can’t stand the small of him, his clothes, his truck, the garage where he smokes etc.
    I also reminded him he’s over forty and has an infant. If he wants to see her graduate, walk her down the aisle, meet his grandchildren he has to stop now.
    I watched four men in my ex inlaws family die of lung cancer plus one in mine. Not pretty.
    I save an average of $50.00 a week since I quit on cigarettes alone. Thats about $2,600.00 a year. Health and life insurance premiums are also lower. There’s probably another $1750.00 a year. Medical bills, doctors, antibiotics, prescriptions for bronchitis eliminated, another $400.00. That’s $4,750 per year savings at just a pack a day scarily healthy smoker. In the 10 years since I’ve quit that amounts to $47,500.00 . I own 3 vehicles I’ve paid of, I have extra in savings, I don’t owe on credit cards. I’m a happy women.

New comments have been disabled.