From: dsc@gemini.tmc.edu (Doug S. Caprette Bldg. 28 W191 x3892)
Subject: Re: Today's conspiracy theory
Keywords: that's an old joke, sonny.
Organization: NASA GSFC CDP VLBI
Date: Fri, 10 Apr 1992 18:30:12 GMT

In article <58hhbg7l@csv.warwick.ac.uk> csuah@warwick.ac.uk (~WISP at CU~) writes:
>In article <1992Apr8.203803.27333@nsisrv.gsfc.nasa.gov> dsc@gemini.tmc.edu (Doug S. Caprette Bldg. 28 W191 x3892) writes:
>>Let's not forget the role that nicotine abuse plays here.  Although up to
>>half the lung cancer from smoking is attributed to radiation exposure.
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>By who? This sounds suspiciously like a tobacco-lobby smokescreen to me.
>
"Physics Today" -- Sometime between 1986, and 1987.

Why would the tobacco lobby claim that up to half the lung cancer they were
causing was due to radioative substances in the tobacco?  This would hardly
be good for business.

Perhaps you didn't read the statement carefully.  The statement was to the
effect  that up to half of the lung cancer due to smoking, was due to
radiation exposure.  *NOT* that it was due *INSTEAD* to radiation exposure.
I.e. smoking *CAUSES* radiation exposure. (see below)

Evidently the statement was so concise, as to be confusing.
>
>The basic problem with smoking is chronic low-level irritation of the
>lining of the lungs (epithelium, squamous metaplasia for those who are
>interested). Chronic irritation of any structure increases the chance of
>cancer (Marjolin's ulcer, Pott's tumor of the scrotum etc...), and when you
>add to this the overtly carcinogenic nature of the PAHs that accompany
>cigarette smoke (it's not the nicotine), you end up with a very high risk
>of developing Ca bronchus.
>
Right.  It's not the nicotine that is the carcinogen.  But it is the abuse of
the nicotine, leading to addiction, that causes the abuser to be exposed to
carcinogens.  People who manage to obtain a prescription for nicotine in a
purer form, can satisfy the addiction with a reduced risk of cancer.  Nicotine
is itself harmful in many other ways however.
>
>Back to that 'attribution', it really does sound like a smokescreen. It's
>impossible to establish a causal link for that hypothesis, just as it's
>very difficult to establish it for smoking. Association and very strong
>
This sentence is a bit too vague to make a direct response.  (Too many pronouns
with uncertain antecedants.)  I have no problem with your application of
logic. 
>
>evidence is enough for anyone with half a brain, but that lets out all the
>people we elect to look after our interests.
>
>The take home message is:
>
>        Dont kid yourself. If you smoke, you are killing yourself.

Glad to read this. At first, I thought *YOU* were an American drug lord 
mouthpiece.
>

The estimation that up to half the lung cancer from smoking is due to radiation
exposure was the result of the discovery of Polonium 210, in tobacco products.
sure was the result of the discovery of Polonium 210, in tobacco products.
A common ore of Uranium also is a source of Phosphorus.  The process used to
extract the Phosphorus from the tailings also carries along Bismuth 210, a 
decay daughter of Uranium.  The Phosphorus is used to make a high phosphate
fertilizer, used on tobacco.  The Bismuth 210 contaminant goes along with it
and beta decays to form Polonium 210.  The Polonium 210 is absorbed and con-
centrated in the tobacco plant. (no biomultiplication factor was given in
Physics Today, does anyone else have one?)  Polonium 210 is an alpha emitter.
Normally, individuals exposed to (low energy) alpha from sources outside their
bodies, are at little risk because they are shielded by clothing, and by a thin
layer of dead, or already dying skin cells.  Low energy alphas do not penetrate
very far in human tissue.  However, the interior of a lung has no such 
protection.  The high mass and strong charge of an alpha make it very damaging
to living cells.  Smokers inhale smoke contaminated with Polonium 210, some
remains behind in the lungs along withthe other contaminants, and some of it
decays, exposing living lung tissue to alphas.

The estimate of 'up to one half' is admittably rather vague.  I presume it
was ased on the observed concentration of Polonium 210 in tobacco pruducts,
together with dose/response relationships established with animal studies.

The Treasury Department regulates liquor to the extent that it is illegal to
sell whiskey which is contaminated with methanol.  However, to my knowledge,
they have not placed any restrictions on the contents of tobacco products.


Xref: sparky alt.folklore.urban:11743 alt.folklore.science:1347