Heh, well, I can see you've drawn your conclusion (ignorantly, but since when does that stop anyone?)

You're comparing apples and oranges throughout, which often happens when attempt science by Google. It's easy to show that some level of carcinogenic something exists in just about anything, including coffee and peanuts. (Saccharin was banned following "It causes cancer!" hysteria of the sort you're perpetuating, but in realistic doses it's less dangerous than either of those.)

I take it you didn't read past the intro of the article from the Annals of Occupational Hygiene, but they're discussing the kind of doses important to people working with large numbers of diesel machines in facilities with "impeded natural ventilation", and they draw comparisons to bus garages, etc. The paper isn't even about carcinogenicity, but let's say my highway drive is somehow as bad as the inside of a bus garage.

They're talking about the effects of being exposed to about 10^-8 g/m^3 of total PAH content during the workday in those kinds of places. By comparison, a single cigarette releases about 3 micrograms of just two proven-beyond-slightest-doubt, potent PAH carcinogens (N'-nitrosonornicotine + (4-methylnitrosamino)-1-(3-pyridyl)-1-butanone) just in the sidestream smoke. (We'll assume the smoker is puffing away vigorously, and not letting it burn in the ashtray, thus absorbing most of the damage with his lungs.) Burning one cigarette that way turns 300 cubic meters of air (a 30'x30' room, 10' high, probably much bigger than any reasonable indoor room) into that level of danger. And all of that generously assumes that all the PAH content of the diesel soot is cancer-causing (it's not), and only those two components of cigarette smoke are present (there's 60+).

Why? Because engines run much hotter, and their input fuel is fairly homogeneous. You don't get a lot of PAHs out because there weren't many in the refined fuel that went in, and most of what went in got oxidized thoroughly anyway. Burning a plant at low temperatures is much different.

So me driving to work? Not even close. Outdoor air dilutes quickly. I'm not there 8 hours a day like the guys working in the bus garage. (Who are allowed to work there all day, because those dosages don't exceed British law.) Even on a bad day of traffic, it's not like the inside of a bus garage. Most vehicles don't burn diesel, for one thing. And I still had to make crazy assumptions to get in that dosage ballpark, neglecting everything else in this paragraph.

Most importantly, it's a lot more reasonable to ask someone not to smoke, than it is to ask them not to drive or clean their house.

Heh, well, I can see you've drawn your conclusion (ignorantly, but since when does that stop anyone?). So, I won't bother arguing with you, but its worth noting that a lot of the stuff you say here is crap. Sucking in exhaust fumes, for one, isn't harmless. The stuff you say about sitting next to someone indoors who is smoking giving you cancer is garbage as well. If you want to just make stuff up, by all means, but don't do it under the pretext of science.

Back at ya. This probably isn't the type of topic that you want to pick a fight with Dr. Valg over, though. I wouldn't lecture you on the finer points of Windows applications or anything.

valguarnera@carrionfields.com