How can we know that
medicines will not cause birth defects without
testing them on animals?
The medical principle called Karnofsky's Law
states that any substance can be teratogenic
(cause birth defects) if given to the right species,
at the right stage in development, and in the
right dose. Common table salt or even water can
be teratogenic to some species in certain circumstances!
Therefore, science has already told us that any
medication can cause birth defects in some creatures.
[4]
In addition, agents that are teratogenic to
some species may have little or no teratogenic
affect in others.[5] Of 1,200 chemicals that
caused birth defects in animals, only 30 were
proven to affect humans. [6] As the book, Chemically
Induced Birth Defects records:
"In approximately
10 strains of rats, 15 strains of mice, 11
breeds of rabbits, 2 breeds of dogs, 3 strains
of hamsters, 8 species of primates and in other
such varied species as cats, armadillos, guinea
pigs, swine and ferrets in which thalidomide
has been tested, teratogenic effects have been
induced only occasionally."[7]
Rats, popular lab animals, have been shown to
get birth defects from almost every chemical
that causes birth defects in humans. But they
also get birth defects from hundreds of drugs
that are safely used by humans! If chemicals
that harm rat offspring do not cause birth defects
in humans, the animal tests are meaningless and
non-predictive.
So what is teratogenicity-testing in animals
good for and why does it continue? As obstetrics
professor Dr. D. F. Hawkins points out:
"The great majority
of perinatel toxicological studies seems to
be intended to convey medical and legal protection
to the pharmaceutical houses and political
protection to the official regulatory bodies,
rather than produce information that might
be of value in human therapeutics."[8]
As Karnofsky's Law postulates, researchers can
eventually inflict birth defects on a species
with substances that are teratogenic in humans.
But to what purpose? Non-predictive animal experiments
are of no human value. They only deplete valuable
research funding that might otherwise be of true
medical value.
Next Question
|
