Future screening would rely on lab cells, robots, computer models
THURSDAY, Feb. 14 (HealthDay News) -- U.S. government scientists proposed Thursday to limit the testing of potentially toxic chemicals on animals and replace it with new high-tech testing methods.
According to an agreement involving the U.S. Environmental Protection Agency, the U.S. National Institutes of Health, and the U.S. National Toxicology Program, toxicity tests will start being done using human cells in laboratories, robots, and computer modeling. This approach should enable researchers to analyze more data on the toxic effects of chemicals -- ranging from pesticides to household cleaners -- more quickly, greatly reducing the need for animal testing, the scientists said.
"The research collaboration we are announcing today really has the potential to revolutionize the way toxic chemicals are identified," Dr. Francis Collins, director of the U.S. National Human Genome Research Institute, said during a morning teleconference.
This collaboration is still a research effort, Collins noted. "In the long term, we might be able to do a better job of predicting toxicity by using these cell-based tests, but we don't know if that's going to be as good as we would like. The purpose of this collaboration is to test this out," he said.
The report outlining the proposal is published in the Feb. 15 issue of the journal Science.
Historically, toxicity has been determined by injecting chemicals into lab animals and watching to see if they got sick. "Though that approach has given us valuable information, it is expensive, it is time-consuming, it uses animals in large numbers, and it doesn't always predict which chemicals will be harmful to humans," Collins said.
New technology has made testing chemicals much faster and more accurate.
"As a society, we need to be able to test thousands of chemicals in thousands of conditions at a much faster rate than we did before," Dr. Elias A. Zerhouni, director of the National Institutes of Health, said during the teleconference. "The idea here is to move the 20th century paradigm of testing one compound at a time in many animals to a 21st century paradigm to test five to 10,000 compounds against 5,000 to 20,000 conditions in cells that are specific to human toxicology."
These new methods include using high-speed, automated screening robots to test suspected toxic compounds, instead of using laboratory animals.
What the federal agencies are trying to do can be seen by comparing what has been done so far with what they hope new technology will allow them to do.
For example, the National Toxicology Program has been in existence for about 30 years. During that time, using animals, the program has tested 2,500 chemicals. However, using the new methods, the testing of 2,500 compounds in 15 different concentrations can be done in a single afternoon, the federal scientists said.
The scientists said it's not clear how long it would take before this high-tech testing is fully implemented. It's also not certain how much animal testing can be eliminated, they said.
Still, one animal-rights group thinks the new plan could be a giant step forward in limiting animal testing.
"We are very excited about this movement in the U.S. government," said Kate Willett, a senior policy adviser at People for the Ethical Treatment of Animals (PETA). "It really does represent a paradigm shift -- a new way of thinking about toxicity testing, which is great."
Not only do the new methods rely less on animals, they do a better job of protecting human health, she said.
"We are hopeful that this prevailing wind will provide momentum needed to overcome the historical inertia that's been prevalent in both the National Toxicology Program and EPA," Willett said. "Both of those groups relied heavily on animals and have been very resistant to moving away from animal testing. We are hoping that this new view will be able to overcome the inertia."
For more on animal testing, visit the Humane Society of the United States.
SOURCES: Feb. 14, 2008, teleconference with Francis S. Collins, M.D., Ph.D., director, U.S. National Human Genome Research Institute, Bethesda, Md.; Elias A. Zerhouni, M.D., director, National Institutes of Health, Bethesda, Md.; Kate Willett, Ph.D., senior policy adviser, People for the Ethical Treatment of Animals (PETA), Norfolk, Va.; Feb. 18, 2008, Science
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