scientific researchers! METHODS TO AVOID EXPOSING ANIMALS TO DANGERS OF EXPERIMENTS AND RESEARCH

“For those familiar with scientific and medical research, the use of animals model for experimental purposes Is common and believed to have contributed immensely to the achievements in Research works.
Nevertheless, it should be realised that these animals are have feelings just as humans. In the process of the experiment, the animals get stressed, tortured, starved and euthanized. Securing a different means of carrying out scientific and medical research without making these animals experience these horrors are possible. The following proves just that.” – Olumurewa Dunmade

The following is a brief overview of some
new test methods available for use in the
high production volume (HPV) program to
reduce or eliminate animal use:

Mammalian acute toxicity can be studied
using cell culture ( in vitro ) systems because
the actions of toxic chemicals are often
focused at the cellular level. For example, a
series of four cell culture tests can predict
toxicity in humans with nearly 85 percent
accuracy (compared to 65 percent in acute
toxicity studies using animals).

Fish acute toxicity is intended to predict the
potential for economic loss and ecological
damage resulting from fish death on a large
scale. If exposure to test substances is toxic
to the food on which fish subsist, fish
populations could be affected even without
direct fish toxicity. It is therefore reasonable
to characterize the toxicity of test
substances to aquatic plants and
invertebrates prior to consideration of acute
toxicity testing on fish. In addition, fish are
often not the most sensitive species, so in
cases where fish acute toxicity is required, a
single fish test can be performed based on
information from algae and shrimp.
In addition, fish acute toxicity can be studied
using computerized ( in silico) test methods
such as ecological structure-activity
relationships (ECOSAR), rather than in vivo
testing, which kills approximately 60 animals
for each test. In fact, no endpoint is better
suited to the use of quantitative structure-
activity relationships (QSAR) tools than
aquatic toxicity. (See the description of
structure-activity relationships below.) Even
the Environmental Protection Agency (EPA)
noted that if a QSAR model is available, it
may be used with the appropriate rationale
for its applicability to the HPV candidate
chemical and identifies ECOSAR (a QSAR
program) as an available model to estimate
aquatic ecotoxicity.

Repeated dose toxicity can be studied using
cells cultured from different body tissues to
estimate the effects of a chemical on
different organ systems. For example,
human liver cells in culture could be exposed
to repeated, low doses of a chemical in order
to study how it is broken down
(metabolized) by the body and to identify
any toxic by-products (metabolites) that
may be produced in the process. Stable
human cell cultures have been produced for
kidney, nervous, immune, reproductive, and
other essential organ systems. A tiered
testing strategy that combines several of
these tissues in culture with the use of
computer and mathematical modeling has
the potential to do away with animal use in
repeated-dose toxicity studies.
Reproductive toxicity and aspects of male
and female reproductive function can be
modeled to some extent in vitro , and
several cellular components of reproductive
organs can be maintained in cell culture.
Although no test method has yet been used
or validated for routine use in reproductive
toxicity studies, it is possible that a battery
of such systems may in the future be able to
model a large proportion of the male and
female reproductive cycles, thereby reducing
or replacing animal use in reproductive
toxicity testing.

Developmental toxicity can be studied in cell
culture using an embryonic stem cell test,
which has been validated by the European
Centre for the Validation of Alternative
Methods as a test for embryotoxicity—a
critical parameter and manifestation of
developmental toxicity. This validated test
method is ideally suited for immediate use
as a reduction measure in a basic,
screening-level program such as the EPA’s
HPV Challenge. Chemicals that test positive
for embryotoxicity could be classified as
probable developmental toxicants without
further testing.

Genetic toxicity can be studied entirely
without the use of animals. Three methods
in particular (the bacterial reverse mutation
test, the in vitro cell gene mutation test, and
the in vitro chromosomal aberration test)
have been accepted by government
regulators worldwide as valid alternatives to
using animals. Combined with information on
metabolism, in vitro methods could replace
the need for in vivo testing all together.
More generally, the following computer-
based modeling approaches have shown
great promise in contributing to the
replacement of animals in toxicity testing:
Structure-activity relationship (SAR)
analyses use computers to seek to predict
adverse biological effects of chemicals based
on their molecular structure, weight, and
electronic charge. SAR data can be used to
estimate whether a specific chemical
produces a particular biological response,
including toxicity, without recourse to
animals. Such approaches have shown 85 to
97 percent accuracy in predicting dermal
sensitization, teratogenicity, and
carcinogenicity for related groups of
chemicals.

Computer-based mathematical modeling
involves the use of computers to model
living biological systems, such as the human
circulatory and respiratory systems. For
example, physiologically based bio-kinetic
models (PBBKs) use computers to study the
absorption, distribution, metabolism, and
excretion of a chemical by the body. They
can also be used to determine the
relationship between the dose of a chemical
and a particular metabolic effect. One such
model, the ED01, studies tumor production in
response to chemical exposure. It can detect
an increased tumor activity of 1 percent, and
at doses of a chemical much lower than
those customarily used in rodent studies.

#source: Peta.Org

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