I would be very cautious about the supposed high readings of mercury in tobacco smoke. Russ, you should check the smoke from other materials, wood, leaves,... since the meter may be falsely responding to the ions in the smoke. Also the smoke from a stand alone cigarette vs the exhaled smoke should be tested i.e. the smoke may act as chelator of mercury from the lungs of a toxic person, hence the exhaled smoke would contain more Hg for the same reason that urine contains more Hg after DMSA or DMPS provocation. The extremely high readings, though, are most indicative of the false reading.

Namely, all references from anti-smoking research on the composition of tobacco smoke give about 1-5 nanograms of Hg per cigarette (e.g. see this paper, p. 18), which is 5/1000 micrograms per cigarette i.e. you would need to smoke a carton of cigarettes for 1 microgram of mecury! For your 100 micrograms per m3 reading, you would need to burn 100 cartons into 1m3. Note also that these 5 ng is the outer end of the measurements, the best shot of the science strongly biased against tobacco smoke (they make big bucks out of peddling its alleged dangers, see below).

If you are a mercury toxic smoker, you may be harming yourself by quitting (or by not taking up smoking, as you will see below).

Tobacco smokers have about 80% more glutathione in active form than non-smokers (smoking is a kind of exercise of immune system). One of beneficial effects of this excess glutathione is about tenfold reduction in rates of Alzheimer's disease of smokers vs non-smokers among ApoE4 allele carriers (these are people with poor detox of mercury from brain and particularly susceptible to Alzheimer's; ApoE4 frequency increases from south to north Europe, hence Nordic countries are most affected by amalgams among Europeans). Tobacco smoke is also highly therapeutic for Parkinson's disease and schizophrenia (possibly due to increase in dopamine and MAO inhibition).

Note that Alzheimer's, Parkinson's and schizophrenia share great deal of symptoms with mercury toxicity of the brain and smoking is significantly therapeutic for all three diseases. So be very careful before jumping into the hands of the Big Pharma, with their nicotine replacements and antidepressants (which don't help at all for your own glutathione stimulation by tobacco smoke). Odds are you will cause yourself much more harm than good.

Tobacco is an ancient medicinal plant and the present anti-smoking propaganda is driven chiefly by the profits of the Big Pharma (also Big Med & "health" bureaucracies), which created and funded almost all of the anti-smoking groups and funds much of the anti-smoking "science" directly (and the rest indirectly via the "health" bureaucracies). The profits of the Big Anti-tobacco come not just from the obscene taxes on cigarettes (imagine suddenly having to pay $100,000 for a car you can now buy for $25,000), but also from selling nicotine replacements, antidepressants (tobacco smoke is therapeutic for anxiety & depression), allergies and asthma (smoking used to be advised by medical textbooks & doctors for these ailments until 1950s), Parkinson's, Alzheimer's, schizophrenia... The ancient medicinal plant, tobacco, is a competitor for the Big Pharma. Many tens of billions are extorted from smokers every year under the cover of the anti-smoking hysteria they whipped up. Few crumbs from the loot go into buying the best anti-smoking "science", "health" bureacrats, politicians, anti-smoking laws and regulations the money can buy.

To get a bit more balanced picture on the subject of tobacco smoking (and avoid harming yourself by falling for the media brainwashing), check the following references:

1. The Scientific Scandal of Antismoking by J. R. Johnstone & P. D. Finch

2. "In Defense of Smokers" by L. A. Colby

3. "Smoking is good for you" by Dr. W. T. Whitby

4. Therapeutic Effects of Smoking (misc. scientific references; also article "World's Oldest -- All Smokers)

5. LF thread on WHO study showing that secondary smoke is protective against lung cancer (lots of discussion and other links)

6. SE thread Tobacco Smoking is Protective Against Lung Cancer (more links & references cited in the discussion; see also on immune stimulus & correlations with diseases)

Now, of course, additive and pesticide laden supermarket cigarettes, like much of supermarket foods, are junk and likely harmful. Filters are also harmful since they shed non-biodegradable fibers.

On the other hand, additive free, organically grown pure tobacco leaf, such as American Spirit, rolled in thin paper (on how to "roll your own" and "stuff your own") or used in a pipe, is the way it was meant to be done, the way our grandfathers smoked it. Tobacco was cultivated for thousands of years as the sacred medicinal plant and real science (unlike the anti-tobacco junk science) is only beginning to uncover some of its magic. Nicotine is just one tiny bit of its medicinal power (that's why nicotine patches or antidepressants don't work for quitting; e.g. they don't stimulate glutathione or act as MAO inhibitors). For example, Coenzyme Q10, the miracle supplement, is actually tobacco leaf, it was discovered there and the best brands are still manufactured from tobacco leaf, even though it can be now synthesized artificially (see Whitby's book #3, also #6).

Note also that the anti-smoking propaganda is peddled largely by the same actors (FDA, CDC, EPA, AMA, NCI) and backed up by the same kind of pseudo-science (and money that buys it) that peddle the theory that "mouthful of mercury is safe and effective" and "thimerosal injected into babies causes them no harm". The same guys, the same alphabet soup agencies, the same money and and the same bought "science".

So, read the materials for yourself, all sides of the story, but before anything else, listen and trust signals from your own body. A single cell in your little toe knows more about biochemistry, genetics and detox at the molecular level than all the science and technology in the world put together. If you were to take all of the world's medical, biochemical and pharmaceutical science & technology in one gigantic team, give them all the money and resources they want and ask them to create one live cell from scratch, they wouldn't even know how to create one organelle, a tiny organ of cell, let alone a whole live cell (or to say nothing about a vastly more complex human organism). Yet, the little "dumb" cells, which are actually unamaginably complex biochemical networks (i.e. distributed, self-programming natural computers of the same kind as human brain), create new live cells from scratch every day all day long, without breaking a sweat, as it were.