The tests covered by REACH (Registration, Evaluation, Athorisation of Chemicals) consist, for the majority of cases, chemical testing on animals. In 2005 it was estimated that it would have been killed up to 50 million. It
experiments on rats, rabbits and dogs to determine whether a substance
- is toxic to humans
- is harmful to human eyes
- is irritating to human skin
- causes cancer or birth defects in humans
- interferes with the human endocrine system (glands, liver, pancreas, etc.)
But significant differences in anatomical, physiological, biochemical and metabolic between organisms of the species on which human experiences and the body, are such as to make reliable and truthful human application of the results animals.
Here are some of the most glaring example.
IRRITATION
How : an animal commonly used, and provided for in the REACH for eye irritation is the albino rabbit. In most cases it is not expected anesthesia. With this experiment we try to identify the irritation caused by a substance that comes in contact with eyes. Is introduced in one eye (the other serves as a control) a predefined quantity of the substance to be tested, and we study the possible reactions: flushing, redness, swollen eyelids, ulceration, lacrimation.
Critique: The ocular responses to a chemical substance is closely related to the anatomy of the eye and the immune status, physiological and genetic animal. And also: •
the human eye is structured very differently than in the albino rabbit. •
our cornea is thicker and covers a lower percentage of ocular surface. •
an ocular membrane (M Bowman's) man is six times thicker. •
our tears is able to expel harmful substances while the rabbit is very low and the substance remains in the eye for longer
• eyelids, which play an important role in the removal of substances, are very different .
The degree of irritation is also evaluated in a totally subjective operator running the test, so the response will depend on its experience and sensitivity and not by objective evidence.
Alternatives: You can alternatively take an integrated study based on mathematical methods, statistical and chemical, for example by simply measuring the pH of the substance. Or make use of other biochemical tests such as measurement of proteins released by the tear fluid after exposure to the substance.
TOXICITY 'REPEATED
How : the repeated dose toxicity testing required by REACH involves the use of 60 rats for each substance and possibly 32 dogs. The experiment aims to identify the toxic effects on humans following the administration of repeated doses of a chemical. The substance analyzed is introduced repeatedly in the animal - usually by force-feeding - for a period 28 to 90 giorni.Durante
the experiment can be observed: •
pressure changes
• anemia • aggression
• muscle weakness • tremors •
• coma and sometimes death
At the end of the test period are killed animals remained alive and passes to the analysis of their tissues and internal organs.
Critique: The way a body reacts to chemicals depends on its metabolism. Between man and mouse (or dog) that are normally made these experiments there are significant differences in metabolism
• the speed with which the substances are metabolized varies depending on the size and weight •
enzymes involved in the processes of reaction vary from species to species
These differences mean that the same substance can be expelled in some animals and accumulated in other, resulting in entirely different effects.
Alternatives: You can use an integrated mathematical and statistical methods and in vitro tests. The first permit to study in detail the chemical and physical characteristics of the molecule and provide a prediction of possible effects. The results can then be confirmed through in vitro studies.
CARCINOGENESIS
Procedure: The test carcinogenesis is provided by the REACH with the use of at least 400 rats for each substance to be tested. Immediately after weaning is administered to young rats the chemical and then evaluate the outcome of exposure through blood, tissues and organs. The test lasts 5 years. All animals involved die of diseases induced during the trial or were killed for carrying out the analysis.
Critique: between the human organism and animals commonly used in testing for carcinogenicity, there are a number of differences that can not be considered for man results. For example: • the speed with which
a substance is metabolized is usually inversely proportional to the size of the animal (in mice and rats, so this process is much faster than humans).
• mice and rats in the B cell growth is very fast (they unamaggiore predisposition to and development of cancer). •
bodies of rats, mice, dogs, cats and hamsters are able to self-produce vitamin C, one of the most important antioxidants and protectors against cancer, while the man needs to take it with food.
Alternatives : testing for carcinogenicity, since the 70's are used in vitro methods that use to bacteria. These tests which have proved crucial in the fight against cancer. For example, thanks to in vitro methods: •
has discovered the mechanism that turns healthy cells into cancer cells
• have identified the characteristics that determine tumor cell proliferation and thus tumor growth.
Nothing really cruelty free because all the substances have been tested on animals in the past as today, what we can do but 'is not buying products with ingredients of the new generation and therefore must be tested for not increasing the vivisection .
Here are the sites for useful information and list no cruelty brands of personal products not tested on animals:)
http://www.lav.it/
http://www.lavocedeiconigli.it/lista_% 20nocruelty.htm
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