From: tara@starburst.umd.edu (Tara McDermott)
Newsgroups: rec.food.veg
Subject: Animal Research - A hazard to health
Date: 15 Dec 92 17:14:54 GMT

Reprinted with permission from AAVS's Health and Humane Research:

Animal Research - A Hazard to Health
------------------------------------

In 1983 the pharmaceutical company Pfizer carried out a special study
to see if animal experiments could correctly identify cancer-causing
chemicals.  The results would be vitally important because despite
costing millions of dollars, no one really knew whether the tests
provided adequate protection against hazardous substances.  Human
findings were compared with experimental data from rats and mice for
all chemicals known to cause cancer in people.  The outcome was
disturbing: in most cases animal tests had given the wrong answer.(1)
The report concluded that we would have been better off to toss a
coin!

Misgivings over the validity of animal research are not new but they
are growing.  The Medical Research Modernization Committee recently
reviewed 10 randomly chosen "animal models" of human disease and found
little, if any, contribution towards the treatment of patients.(2)
They discovered, for instance, that chemically-induced cancer of the
colon in rats was not relevant to our understanding, diagnosis and
treatment of human colon cancer.

The problem is that artificially induced disease in animals is never
identical to the naturally arising disorder in people, making animal
research a logically flawed process.(3)  Yet doctors have known for
more than a century that human disease can take an entirely different
form in animals.  During an investigation of cholera in the 1880's,
the famous German microbiologist Robert Koch repeatedly failed to
induce anything similar in animals(4) while contemporary scientists
are having the same difficulty with AIDS.  Even chimpanzees do not
develop the disease when inoculated with HIV.(5)

It is not only animal models of infectious disease that present
problems.  In 1980 an editorial in the cancer research journal
"Clinical Oncology" asked why so much attention is devoted to the
study of animal tumors when "it is... hard to find a single common
solid human neoplasia (cancer) where management and expectation of
cure has been markedly influenced by laboratory research."  The writer
explained that most human cancers behave differently to the
artificially produced animal model and concluded that it is the study
of human patients that will ultimately yield relevant results.  And in
January, 1990, a similar editorial in the journal "Stroke" referred to
the dubious relevance of animal models: of 25 drugs found useful in
treating animals with artificially-induced stroke over the past 10
years, none had worked in clinical practice.  The editorial,
contributed by researchers at the Mayo Clinic, concluded that
"ultimately... the answers to many of our questions regarding the
underlying patholophysiology and treatment of stroke do not lie with
continued attemps to model the human situation perfectly in animals,
but rather with the development of techniques to enable the study
of... living humans."

There are also countless examples where medicines and naturally
occurring body chemicals react differently in people and animals:(4)
morphine sedates humans but excites cats; cortisone produces birth
defects in mice but not people, while thalidomide works the other way
around; doses of aspirin used in human therapeutics actually poison
cats while having no effect on the treatment of horses; acetylcholine,
a chemical produced by nerve endings, dilates the coronary arteries of
dogs but has the opposite effect in people(6), while another naturally
occuring body chemical, serotonin, raises the blood pressure in dogs
but reduces it in cats; insulin produces deformities in laboratory
animals but not people; and rats, mice, dogs and cats do not need
vitamin C added to their diet but, like us, guinea pigs do.

With such differences tests on animals can be either worthless or
positively dangerous because they provide a false sense of security.
Recent examples are the heart drugs encainide and flecainide.
Approved in 1987 following the usual animal tests, the drugs may have
caused as many as 3,000 human fatalities.(7)  In the case of Oraflex,
unforeseen effects actually led to the drug's withdrawal from use.(8)
Deaths occured mainly through liver damage but company literature
stated that "the effects of benoxaprofen (Oraflex) in the rhesus
monkey were studied for one year... There were no apparent adverse
effects on survival."

The failure of animal tests to warn against toxic hazards is not
unusual.  A report by the General Accountng Office found that 51.5% of
198 drugs approved by the FDA between 1976 and 1985 caused serious
adverse reactions after they were marketed, including heart failure,
anaphylaxis, respiratory depression and arrest, convulsions, seizures,
kidney and liver failure, severe blood disorders, birth defects and
fetal toxicity, and blindness.(8)  The effects must have been
unexpected because they resulted in withdrawal from use or, more
commonly, substantial labeling changes either limiting the population
for which they were intended, or adding major warnings or precautions
for their use.  All the drugs were animal-tested in accordance with
FDA guidelines.

There is also the risk that worthwhile therapies may be lost or
delayed.  Had penicillin been tested on guinea pigs, to whom it is
fatal, this valuable antibiotic could have been discarded.(4)  On the
basis of animal tests, the anti-rejection drug FK506 was feared to
toxic for humans and if it hadn't been given as a last chance option
to transplant patients in a "desperate plight," its life-saving
results may never have been appreciated.(9)  Furthermore, experiments
with dogs suggested that FK506 would give better results if combined
with another drug, cyclosporin.  However, clinical experience showed
the opposite with FK506 actually INCREASING the kidney toxicity of
cyclosporin.(9)

The evidence suggests that vivisection is an error not only because it
often produces the wrong answer, but because it diverts attentiuon and
resources from more reliable sources of information based on the study
of people.  The consequences can be devastating.  Unsuccessful
attempts to induce lung cancer in laboratory animals by forcing them
to inhale tabacco smoke, cast doubt on human clinical findings,
delaying health warnings and costing thousands of lives.(3)  The
discovery that excessive alcohol consumption leads to cirrhosis of the
liver has been doubted by the failure to produce similar effects in
virtually all laboratory animals tested.(10)  Only in baboons has
cirrhosis been induced although even this has not been confirmed by
other researchers.

With the constant risk of misleading predictions, claims by animal
research advocates that vivisection is responsible for every medical
advance, make no sense.  For how can a method which produces such
conflicting results be so vital to our health?

-----------------------------------------------------------------------

There are other ways in which animal tests pose a threat to our
health.  Failure to transmit AIDS to other species has led scientists
to develop a completely new laboratory animal.  By inserting parts of
the human immune system into mice, researchers believed they had
produced an animal model of AIDS.  But it is now feared that
interaction of HIV with viruses commonly found in mice may not only
make the model irrelevant but promote dangerous changes in the AIDS
virus.  The new HIV variants could then spread by entirely different
routes, possibly even through the air.(11)

Further doubt is cast on the vailidity of animal research because the
species most often employed are usually chosen on non-specific grounds
such as cost, ease of handling and laboratory tradition.  Rabbits are
the favorite animal for eye irritation studies because they are cheap,
readily available, docile and have large eyes for assessing test
results.  Yet there are major physiological and biochemical
differences which make the rabbit eye a bad model for the human
eye.(4)

For economic reasons, small rodents are the most used animals in
toxicity tests yet they are known to be the most unsuitable models for
people in the way they matabolize or break down chemicals in the body.
A comparative study of 23 chemicals showed that in only 4 cases did
rats and humans metabolize products along the same metabolic
pathway.(4)  This is important because variation in drug responses can
often be traced to differences in metabolism.

Although pigs have a coronary vascular system more similar to that of
people, they are expensive and difficult to work with and coronary
circulation studies overwhelmingly employ dogs instead.

---------------------------------------------------------------------

"...while conflicting animal tests have often delayed and hampered
advances in the war on cancer, they have never produced a single
substantial advance either in the prevention or treatment of human
cancer."   - Dr Irwin Bross, Roswell Park Memorial Institute for
Cancer Research, Congressional Testimony, 1981

"The unsatisfactoriness of preducting adverse effects in humans from
animal experiments has been known for a long time.... Every species
has its own metabolic pattern, and no two species are likely to
metabolize a drug identically."   - M. Weatherall, former Director of
Wellcome Research Laboratories, "Nature", April 1, 1982

The LD50 test, where animals are deliberately poisoned to death to
find a numerical index of toxicity.  Scientists at Zurich's Instutute
of Toxicology have concluded: "For the recognition of the symptomatol-
ogy of acute poisoning in man, and for the determination of the human
lethal dose, the LD50 in animals is of very little value."    
    - "Archives of Toxicology", 1981, vol. 47, 77-99

Examples of Medicines Withdrawn on Safety Grounds from the US
Market(8):
Drug (purpose)		     Brand Name	     Launched	Withdrawn
-----------------------------------------------------------------
Ticrynafen (diuretic) 	      Selacryn	 	1979	  1980
Benoxaprofen (analgesic)      Oraflex		1982	  1982
Zomepirac (analgesic)	      Zomax		1980	  1983
Nomifensine (antidepressent)  Merital		1984	  1986
Suprofen (analgesic)	      Suprol		1985      1987

----------------------------------------------------------------------

References:

(1) D. Salsburg, "Fundamental & Applied Toxicology", 1983, vol.3,
63-67.

(2) S.R. Kaufman et al, "Perspectives on Animal Research", 1989,
vol.1, Supplement.

(3) "A Critical Look at Animal Research", Medical Research
Modernization Committee (NY, 1990).

(4) R. Sharpe, "The Cruel Deception - the use of animals in medical
research" (Thorsons, 1988) and references therein.

(5) P. Newmark, "Nature", 1989, October 19, 566-567.

(6) S. Kalsner, "Journal of Physiology", 1985, vol.358, 509-526.

(7) "Washington Times", 1989, July 26.

(8) "FDA Drug Review:  Postapproval Risks 1976-1985" (US General
Accounting Office, April 1990).

(9) R. Allison, "Journal of the American Medical Association", 1990,
April 4, 1766 and references therein.

(10) O. Ray, "Drugs, SOciety & Human Behaviour", (C.V. Mosby Company,
1978).

(11) J. Mrx, "Science", 1990, February 16, 809.

--
Tara McDermott                                  tara@starburst.umd.edu

Sweet and sweet is their poisoned note, the little snakes' of silver throat,
in mossy skulls that nest and lie, ever singing "die, oh! die."
Newsgroups: rec.food.veg