Animal testing, minimizing

Animal toxicological and in vitro studies. In animal or in vitro studies the system is more controlled than in human studies, the external influences are minimized (more in in vitro than in animal tests). However, in both cases, an extrapolation is required interspecies in the case of animal studies and at least from system to organism extrapolation in the case of in vitro test. 

Preclinical and clinical process laboratories serve a critical function in the development and organization of toxicology data, animal testing results, and ultimately of human test results. Again, the GLPs provide guidance and assure both minimization of misinterpretation and control of both the potential risks to human subjects and the suffering of test animals. 

The test procedure described in ASTM E 1678 minimizes the number of animal tests. In this test procedure, a specimen is exposed to a radiant heat flux of 50kW/m2, and the products of combustion are collected in a 0.2 m3 chamber. Test duration is 30 min. Additional tests are performed with specimens of different size to find the exposed area that is expected to result in 50% lethality of test animals exposed over the 30-min test duration to the atmosphere in the chamber. The lethality is determined on the basis of analytical measurements of the composition of the contents of the chamber and the N-Gas model (see Equation 14.20). To verify the results, two additional tests are conducted with 70% and 140% of that specimen area and six rats exposed to the gases in the chamber. 

This test uses an in vitro human dendritic cell culture to obtain information of the potential for various chemicals to induce allergic contact dermatitis. This test is used as an alternative to the Local Lymph node assay (LLNA) to minimize or replace the use of live animal testing for predicting skin sensitization (Kimber et al. 2002, see below). The test allows for evaluation of skin sensitization by examining the presence of cell surface markers on Periperal Blood Mononuclear Cell (PBMC)-derived dendritic cells (DC) that are known to be involved in the development of allergic contact dermatitis. 

Minimizing the use of animal testing in determining the potential risks of chemicals. 

This approach could also be used to predict skin swelling, Zein test scores, or even CAM-VA skin or eye scores. If the objective is to minimize laboratory and animal testing and to produce rapid and reliable results, I would suggest employment of mathematical models such as those mentioned earlier, but with refinements as indicated. Then after calculation, with many potential formulations, a few of the surviving formulae can be tested for confirmation by the laboratory or animal model. 

It is estimated that approximately 63,000 chemicals are in common use and that significant quantities of several hundred new chemicals are added to the environment every year/ A number of chemicals have been shown to be carcinogenic for humans. It is essential, therefore, that those presenting a risk be readily identified so they can be either removed from the environment or at least regulated to minimize further exposure. Traditionally, chemicals are evaluated for their carcinogenic potential in conventional animal test systems that are costly and time-consuming. Because of such limitations, only a few hundred chemicals can be tested yearly. 

The second type of tests which are briefly described are tests on animals. Such tests have been helpful in the past to investigate the irritation potential of new ingredients with minimal information on them before running tests on humans. These animal tests are only used in very specific cases when no other alternative exists and should be discontinued in the near future. 

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