An article published by the Associated Press, dated February 14th, indicates there may be an end in sight to live animal testing of potentially toxic chemicals and products as it relates to the safety of human usage of these chemicals.
The Environmental Protection Agency, the National Toxicology Program and the National Institutes of Health have signed a "Memorandum of Understanding" to develop and implement new methods of testing. The "new" technique is known as high throughput screening (HTS). It is currently being used in the pharmaceutical industry for drug development, and by genomics researchers. It involves combining chemicals with human cells. Robotic machinery can then determine, within minutes, if there are any signs that the chemical being tested requires further investigation -- i.e. damage to the cells, changes to cellular structure, or even cell death. Similar technology is expected to help reduce animal testing in Europe.
The intent of the agreement is to increase the number of chemicals tested, and improve the validity of the data. Tests done on animals do not always accurately predict how human cells will react with a particular chemical. In addition, the expectation is that the cost to test new drugs and chemicals will be markedly decreased as the time and resources required to fully test a new chemical will be drastically reduced.
According to a related article in the New York Times today (Feb. 15), the main testing agency, the National Toxicology Program, has fully tested just 2,500 chemicals in 30 years. The new approach could screen that many chemicals, at 15 different exposure levels, in a single afternoon, said Christopher Austin of the NIH's Chemical Genomics Center. That could significantly reduce or even eliminate the backlog of new drugs awaiting testing/approval.
Information from these tests will then be combined with data from previous animal tests and computer modeling to predict likely outcomes. Scientists will have to retest proven chemicals with the new technology (HTS) and compare the results with years of previous animal research to see if the new testing is as reliable at predicting harm. Currently HTS is used to test positive results as scientists are searching for chemicals and drugs which perform a certain function. HTS will now be used to look for negative results: damage to human cellular structures.
The agencies acknowledge that full implementation of the shift in toxicity testing could take years because it will require scientific validation of the new approaches.
It's a wonderful example of what scientists always hope for, says Francis Collins, director of the NIH's National Human Genome Research Institute. "You develop a technology for one purpose, and you realize, 'Goodness! We can use it for something else!' "
We're still a bit removed from the day when animal testing will no longer be deemed "necessary." The expectation is that HTS will be tested and further refined over the next five years.
According to Dr. Catherine Willett, of PETA, "These agencies have been resistant to change in the past and this represents a paradigm shift in their thinking. There is no reason to use animals for specific toxicology tests. You can replace them with a battery of non-animal methods designed around the biology."