Cigarettes and the environment...

Sure PM2.5 aren’t the smallest particles - people are even trying to focus on the issues of nanoparticles nowadays. But there is a lot better understanding of the increased risk of PM2.5, and the measurement of PM2.5 from human causes, as opposed to the ultra-ultrafine PM0.1 and under particles.

Well, no, you can’t do that, but how does one break down the exact makeup of the entire atmospheric content of PM2.5 over the United States? It’s difficult to do so even for a single point source emission. Within the scope of Cecil’s column, his generalization was valid. Cecil’s column is not a peer-reviewed paper to be sent to pulmonary researchers, nor a white paper on external air pollution. In short, you are making some valid points here, and we appreciate them, but I believe that within the scope of the column what Cecil said was a decent summary. If you look at the United States or EU regulations on PM10 and proposed regulations on PM2.5 from the EPA, they do not break down limits based on an ultimate analysis of the particles, they base their limits on the macroscopic lump sum of “we know this stuff is bad; we don’t need to dig into it that much” standpoint. And yes there are some specific items sometimes called out separately, but particulate emissions standards generally are a bulk lbm/MBtu, grains/ft3, ppm, or mg/Nm3 (or something like ng/J in Japan IIRC).

This is a little off-topic I guess, and sort of a squishy question to boot, but how do elevated health risks from “environmental” tobacco smoke compare to risks from other pollutants?

For example, I live in LA county. Does breathing some secondhand smoke really add all that much to my risk of heart attack/lung disease, considering I breathe smog and smoke from forest fires anyway?

I’m prepared to believe that secondhand smoke poses health risks, but so does eating mushrooms. How much should I worry?

Una: “Well, no, you can’t do that, but how does one break down the exact makeup of the entire atmospheric content of PM2.5 over the United States?”

What one would do is to try to get an estimate. You would estimate how much comes from cars, how much comes from power plants, etc, and then estimate the relative seriousness of each one.

But if it were the case that it was not possible to do what you are thinking is not possible, then you just should not reach a conclusion, rather than concluding outdoor secondhand smoke is not a serious problem.

" Within the scope of Cecil’s column, his generalization was valid."

No, it wasn’t-- not all particulates are of equal harm, just like now all white powders are the same. They really can vary quite a bit chemically.

" Cecil’s column is not a peer-reviewed paper to be sent to pulmonary researchers"

If someone’s conclusion cannot be supported, he should not reach it. If you make a claim it really should be able to stand up to scrutiny by someone who really knows what is going on. I can’t see how you could think otherwise. When I tell you things about secondhand smoke it is because I really know they are true and I would be happy to have experts examine what I said.

The same standard for accuracy that is used in peer review should be used in any scientific claim. In a forum like this it is not necessary to meet the peer review standards for historical backround and references, but things should be scientifically correct.

" I believe that within the scope of the column what Cecil said was a decent summary. If you look at the United States or EU regulations on PM10 and proposed regulations on PM2.5 from the EPA, they do not break down limits based on an ultimate analysis of the particles, they base their limits on the macroscopic lump sum of “we know this stuff is bad; we don’t need to dig into it that much” standpoint."

If they did that then it is not so good, but I do not believe they do that. For example the EPA treats lead particles quite differently than other particles–lead has largely been removed from gasoline and indoor paints. They do not consider all particulates from burning gasoline to be the same. I also doubt they treat asbestos dust like regular dust.

The EPA classified secondhand cigarette smoke as a class A carcinogen, the most dangerous classification. They have not done this for "standard smoke.

“Ed” writes: <<Paul, look. I don’t mean to be unkind. But your idea that outdoor tobacco smoke is killing people is pretty out there.>>

It seems counter-intuitive to you, but that is not science. As I have said before, it is well-known that the dose response to secondhand smoke is counter-intuitive. For example, in the Harvard study I linked earlier, it was mentioned that light exposure to secondhand smoke for short periods of time lowers prostacycline levels in non-smokers almost as much as regular smoking does in smokers.

You are assuming a physiological situation that does not match what is actually occurring. You risk making errors when you make the sort of intuitive assumptions you are making.

" If you want to make the argument, more power to you. But it’s not up to me to prove that outdoor smoke isn’t dangerous, it’s up to you to prove that it is."

Actually it IS up to you to prove that outdoors cigarette smoke is dangerous, because you made that claim!!! I actually never made a claim as to whether or not it is, but rather that it is plausible that it is, and that your dismissal is based on an erroneous tacit assumption that the dose/response effect will be linear at low doses, an assumption that has already been shown to be incorrect.

fgasparini: “This is a little off-topic I guess, and sort of a squishy question to boot, but how do elevated health risks from “environmental” tobacco smoke compare to risks from other pollutants? For example, I live in LA county. Does breathing some secondhand smoke really add all that much to my risk of heart attack/lung disease, considering I breathe smog and smoke from forest fires anyway?”

The fact that you are exposed to other pollution does not negate the effects of secondhand smoke. If anything, the secondhand smoke will amplify the effects of the other pollution. For example, the 1982 Surgeon General’s Report said it was hard to detect an elevation in lung cancer in non-smokers living in polluted areas from the pollution, but it was possible to detect it in smokers. (Most of the effect in smokers though was from the smoking itself.

I don’t think you would think that if you had diabetes you would not need to be concerned about having high cholestrol.

The LA area, despite its bad air pollution actually has a very low lung cancer ratte, due mainly due to fewer people smoking, and also due to less secondhand smoke exposure.

Indeed there was a study done on Seventh Day Adventists living in the smoggiest parts of California. Seventh Day Adventists not only do not smoke, but tend to assiciate with other Seventh Day Adventists, and therefore have unusually low secondhand smoke exposure. Despite living in a very polluted area, their lung cancer rate was less than half of a typical non-smoker.

“I’m prepared to believe that secondhand smoke poses health risks, but so does eating mushrooms. How much should I worry?”

The standard estimate is that around 53,000 non-smoker die each year in the U.S. from secondhand smoke (not to be a harper–but the methods used to get that number actually underestimate the actual number), making it the third leading preventable cause of death. This is more than the number of people killed by murder/homocide, and way more than the number of people killed by drunk drivers. Here is an editorial in the Journal of the American Medical Association about this.

Well now we’re mixing heavy metals, which in and of themselves are toxic, with particulates in general. And it’s not particulate lead which is regulated, it’s lead, period, IIRC. While some of it will be particulate, the lead is not regulated based on its form. Likewise proposed mercury standards from power plants do not discriminate between elemental, oxidized, and particulate mercury sent into the environment.

“Well now we’re mixing heavy metals, which in and of themselves are toxic, with particulates in general. And it’s not particulate lead which is regulated, it’s lead, period, IIRC. While some of it will be particulate, the lead is not regulated based on its form. Likewise proposed mercury standards from power plants do not discriminate between elemental, oxidized, and particulate mercury sent into the environment.”

What I was saying was that lead particulates are treated differently than non-lead particulates.

If there were a substance that occurred only in a particulate state that was as harmful as lead, I’m sure you would agree the EPA would (or at least should!) treat it more seriously than typical particulates.

This doesn’t seem like a fruitful line of discussion. The fact that something sounds plausible to you doesn’t make it my job to chase down facts to support or refute your conjecture. You come up with something solid - about tobacco smoke in the OUTDOOR environment, mind - and we’ll go from there.

“This doesn’t seem like a fruitful line of discussion. The fact that something sounds plausible to you doesn’t make it my job to chase down facts to support or refute your conjecture. You come up with something solid - about tobacco smoke in the OUTDOOR environment, mind - and we’ll go from there.”

Ed, you keep forgetting that I did not actually take a position, YOU did.

You claimed that you knew for a fact that it was impossible for secondhand smoke outdoors to be harmful, and I told you that you need to be careful about your assumptions. So now you are coming back at ME demanding I supply proof of something. It is you who the demand should be made of, because it is you that took a position.

I hope you are not doing what you just did on purpose.

You assumed that all smoke is chemically identical. You need to prove that. (You can’t, because it is not true.)

Noted.

Thanks Ed.

I argue with lots of people on the internet about various things, and almost always they turn out to be unreasonable.

I appreciate you wanting to be fair and accurate.