I am having DSL problems at home (should be corrected Monday), so I can't
answer personal email until later.  This is being posted at a University
computer, via the magic of a zip disk (why didn't I think of this
before?).
 
While my introduction into this debate was unintentional, and I want
to emphasize this is NOT a discussion of people smoking, or taxes, or
dozens of other straw men (issues of little significance or application,
brought up to be shown as easily defeatable ideas) designed to deflect
responsibility from the smoker, I cannot shun the subject.  I also wish
to bring the discussion back to ferrets, and urge people to ignore straw
men and other insignifica and instead concentrate on the REAL issue: "is
it ethical or moral to subject ferrets to second hand smoke?"
 
To answer the question, it MUST be first demonstrated that ferrets are
susceptible to the health risks of second-hand cigarette smoke.  One of
the comments I received to the reposting of the dangers of environmental
smoke to ferrets was that it was old (1996) and only a single reference.
True enough, but research has moved well past that older reference.  I
have done an extensive search of the current publications and found 93
RECENT references that use ferrets (yes, in lab research, and yes, they
were euthanized) to test human medicines, the influence of beta-carotene,
the proliferation of cancer cells in the lungs, and the intake of
cancer-causing agents.  Rather than filling a dozen FMLs with data
non-smokers will gleefully crow over, or that smokers will ignore and
deny as insignificant, I will only mention 5 of them.
 
Citation 1: Liu, Chun, Lian Fuzhi, Donald E. Smith, Robert M. Russell,
and Xiang-Dong Wang.  2003  Lycopene Supplementation Inhibits Lung
Squamous Metaplasia And Induces Apoptosis Via Up-Regulating Insulin-Like
Growth Factor-Binding Protein 3 In Cigarette Smoke-Exposed Ferrets.
Cancer Research 63: 3138-3144.
 
This is a reference that discusses the effects of a chemical on lowering
the danger of lung cancers in ferrets exposed to second-hand smoke.  I
emailed one of the authors, asking specifically why ferrets were selected
as the research model, and the reason given was "=85Because they are so
susceptible to lung cancers from environmental cigarette smoke=85.and
they are good models for human infants."
 
The sharp rise in the laboratory use of ferrets in lung cancer research
supports this contention.  In the mid-1990s, few ferrets were being
sacrificed towards this work, but currently, DOZENS of research groups
are using ferrets BECAUSE they are so vulnerable to cancers caused by
environmental smoke (second-hand) smoke.  These ferrets will live short
lives and die, and the ultimate reason is the attempt to discover
treatments for humans sucking smoldering carcinogenic, chemically treated
vegetation.  So, in the long-term ethical look at the subject, not only
do smokers cause harm to their own ferrets, but also to other ferrets
they never even meet.
 
Citation 2: Liu, Chun, Robert M.  Russell, and Xiang-Dong Wang.  2003
Exposing ferrets to cigarette smoke and a pharmacological dose of
beta-carotene supplementation enhance in vitro retinoic acid catabolism
in lungs via induction of cytochrome P450 enzymes.  Journal of Nutrition
133:173-179.
 
"These findings suggest that low levels of RA (retinoic acid) in the lung
of ferrets exposed to cigarette smoke and/or pharmacological doses of
beta-carotene may be caused by the enhanced RA catabolism via induction
of CYP, CYP1A1 and CYP1A2 in particular, which provides a possible
explanation for enhanced lung carcinogenesis seen with pharmacological
doses of beta-carotene supplementation in cigarette smokers."
 
There are two obvious implications here, the first being the same one as
mentioned for the first reference.  The second one is dangers of using
UNTESTED supplements.  Researchers found humans eating large amounts of
beta-carotene-containing foods had lower rates of specific cancers
compared to those humans that do not.  The obvious reason was
beta-carotene, which was dutifully given to cancer patients.  It was
quite a surprise to learn beta-carotene had the opposite effect on some
cancers, including lung cancer, making the cancer grow even faster, and
turning it more deadly.  The point is, even if a substance has positive
benefits of one species for one disease, there is not necessarily a
positive benefit in other species or for other ailments.  The reason
ferrets are the models of choice for this phenomenon is because of
their carcinogenic sensitivity to environmental smoke and chemical
supplementation.
 
 
Citation 3: Wolf, George.  2002  The effect of beta-carotene on lung
and skin carcinogenesis.  Carcinogenesis 23:1263-1265.
 
"The induction of pre-cancerous squamous metaplasia in lungs of ferrets
by high doses of dietary beta-carotene (BC) and cigarette smoke is
compared with and contrasted to the different effects of high doses of
dietary BC on skin papilloma and carcinoma induction by the two-stage
carcinogenesis protocol.  Whereas high dietary BC can inhibit the
conversion of skin papillomas to carcinomas, such treatment would not
be expected to inhibit smoke-induced lung tumors."
 
This is independent support of the first two references, as well as my
implications.  Second-hand smoke is extremely dangerous to ferrets, and
just because a supplement has been found to work for one thing, that
success has no bearing on other applications.
 
Citation 4: Liu, Chun, Xiang-Dong Wang, Roderick T. Bronson, Donald E.
Smith, Norman I. Krinsky, and Robert M. Russell.  2000   Effects of
physiological versus pharmacological beta-carotene supplementation on
cell proliferation and histopathological changes in the lungs of
cigarette smoke-exposed ferrets.  Carcinogenesis 21(12):2245-2253.
 
"In the present study, ferrets were given a physiological (low) dose or
a pharmacological (high) dose of beta-carotene supplementation... and
exposed to cigarette smoke for 6 months."
 
The implication here is that it only takes six months of exposure to
second-hand smoke to cause significant (measurable) carcinogenic damage
to ferrets.  Six months!  Admittedly, this is constant exposure to
environmental-smoke, but I HAVE been in private homes where room air was
hazy because of the presence of so much cigarette smoke.  In one case,
it actually took hours to clean my cameras from the deposited tars and
other substances, and my car smelled like cigarette smoke for a week
afterwards.
 
Citation 5: Wang, Xiang-Dong, Chun Liu, Roderick T. Bronson, Donald E.
Smith, Norman I. Krinsky, and Robert M. Russell.  1999
Retinoid signaling and activator protein-1 expression in ferrets given
beta-carotene supplements and exposed to tobacco smoke.  Journal of the
National Cancer Institute 91(1):60-66.
 
"In this study, we used an animal model system to evaluate the hazard
associated with a combination of high-dose beta-carotene supplementation
and tobacco smoking.  Methods: Ferrets were given a beta-carotene
supplement, exposed to cigarette smoke, or both for 6 months.  Cell
proliferation and squamous metaplasia in lung tissue were assessed by
examination of proliferating cell nuclear antigen expression and
histopathologic examination, respectively." "A strong proliferative
response in lung tissue and squamous metaplasia was observed in all
beta-carotene-supplemented animals, and this response was enhanced by
exposure to tobacco smoke."
 
Again, it only took 6 months for the exposure of ferrets to environmental
smoke for it to cause significant (measurable, locatable, and
quantifiable) damage to their lungs.  Think about this; a researcher
WANTS to have a significant number of research animals DISPLAYING
problems, so the exposure to the agent is generally designed to cause
problems in at least 50% of the animals.  Most researchers want a higher
percent of those impacted so they can use fewer total animals, so they
design the exposure to increase the number of them having problems.  What
this means is that a six month exposure to environmental cigarette smoke
causes a SIGNIFICANT risk of lung damage in ferrets, but the implication
is that smaller exposures are just as risky.  In other words, for some
ferrets, far less than 6 months of exposure could cause the same amount
of damage.  For example, if it took 6 months to cause significant damage
to 36 ferrets, then it can be expected that 3 months of exposure could
cause damage to perhaps 18 ferrets out of 36, 1.5 months to 9 ferrets
out of 36, and 3 WEEKS to harm 4 to 5 ferrets out of 36!
 
Smokers LOVE to argue the exposure the force on ferrets is "minimal",
but they don't flush their lungs and blood from carcinogenic chemicals,
don't change their clothes, and don't understand that TINY exposures add
up to large ones.  Why?  Remember the reposted reference?  The particles
that cause damage tend to become trapped in lung tissue.  Ferrets breathe
in tiny exposures, the carcinogenic particles are trapped, and they
accumulate over time.  While, depending on the individual smoker, the
ultimate exposure will vary from individual ferret to individual ferret,
even TINY doses can AND WILL add up over time.
 
So far, all of this has been part of the "proof of danger" part of the
argument.  Smokers may ignore dangers, deny them, or even rant about
taxes or pesticides or even "bubble ferrets" and other straw men, but
those rants DO NOT address the simple questions of ethics and morality of
the question, "Is it right to expose innocent victims to environmental
cigarette smoke?"  Rant all you will, THAT is the ultimate question, and
one I will answer tomorrow in my next post.
 
Bob C
[Posted in FML issue 4271]