High Speed Robots to Replace Animal Testing of Toxic Chemicals

Currently, data collection to determine chemical toxicity currently relies on live animal tests. Researchers expose an animal, such as a mouse, to a chemical. They observe the general effects of the compound on the animal, such as causing weight loss or shortening life, and then examine the animal's tissues for evidence of damage.

But experts at the two government agencies say the growing number of new chemicals, high testing costs and public unease with animal testing has led to the search for alternate toxicology testing methods.

The five year memo of agreement announced today details a collaboration between two NIH institutes and the EPA to use the NIH Chemical Genomics Center's high-speed, automated screening robots to test suspected toxic compounds.

Kalypsys robots at the National Human Genome Research Institute stand ready to analyze chemical compounds for toxicity. (Photo by J. Mainquist courtesy NHGRI)

This system uses cells and isolated molecular targets instead of laboratory animals. Experts say the suite of ultra-high throughput robotic technologies can screen the biological activity of more than one million chemical compounds per day to determine their possible toxic effect.

"I launched the NIH Roadmap for Medical Research five years ago to create collaborations between institutes and centers on big projects that none of them could do alone. But I never envisioned a trans-agency collaboration testing for environmental toxins," said NIH Director Elias Zerhouni, MD.

"This research collaboration has the potential to make crucial discoveries that will protect the public health by identifying and understanding chemical toxicants to which people are exposed," Zerhouni said.

This new, trans-agency collaboration is expected to generate data more relevant to humans; expand the number of chemicals that are tested; and reduce the time, money and number of animals involved in testing, officials of both agencies said.

The idea is to jumpstart a collaborative effort across the toxicology community to rely less on animal studies and more on in vitro tests using human cells and cellular components to identify chemicals with toxic effects.

The strategy calls for improvements in dose-response research, which will help predict toxicity at exposures that humans may encounter.

Kate Willett, PhD, science policy advisor with People for the Ethical Treatment of Animals, PETA, said the organization is "excited" about the prospect that these agencies are attempting to incorporate modern science into the toxicity testing process.

"This is a really big change, and these agencies have been really resistant to change for many years," Willett said.

"We've been very frustrated with the EPA. They haven't been able to ban a single toxic substance in more than a decade because they have relied on animal studies," Willett said. "These are so variable that they don't give you an answer that you can make a judgement on. The new methods will be more effective because they give a quantifiable answer that is repeatable and that you can make a decision on."

The five year memo of agreement announced today builds on the experimental toxicology expertise at the National Toxicology Program, headquartered at the National Institute of Environmental Health Sciences, the high-throughput technology at Genomics Center managed by the National Human Genome Research Institute, and the computational abilities at the EPA's recently formed National Center for Computational Toxicology.

The emerging science of computational toxicology is the blending of modern computer science with molecular biology, the scientists said.

"As our detailed research strategy continues to develop, we will welcome the participation of other federal partners, as well as interested public and private sector organizations, to make this vision of 21st century toxicology a reality," said EPA's George Gray, PhD, assistant administrator for EPA's Office of Research and Development, which includes the National Center for Computational Toxicology.

The EPA's work with the NIH is part of its 2007 ToxCast™ program that will use advances in computers, genomics and cellular biology to speed up toxicity testing and enhance capacity to screen new compounds.

"We now are seeing tools newly available to us for chemical genomics research deployed for greater refinement, speed and capacity in chemical toxicity screening," said Francis Collins, MD at the National Human Genome Research Institute.

Dr. Andrew Rowan, executive vice president, Humane Society of the United States, said his organization has been advocating a shift away from traditional animal testing towards alternative methods based on a modern understanding of human biology for more than 40 years.

"This project could eliminate the pain and distress of thousands of animals and be seen as a follow-up, with equally visionary possibilities for biology, to the NHGRI's highly successful Human Genome Project," he said.

But Rowan put a price tag on the project, saying, "In order for this vision to be fully realized within a decade, what is needed overall is an international government/industry effort funded at approximately $200 million per year, or approximately four times the current level of effort."

"The experimental and computational expertise required to transform toxicology is an enormous undertaking and too great for any of our existing organizations to accomplish alone," said John Bucher, PhD, associate director of the National Toxicology Program.

The National Toxicology Program will contribute thousands of compounds for testing along with a large database of the chemicals' effects on animals, for comparison with the new cell-based data that result from the robotic tests.

The new agreement is part of a 14 agency federal effort announced last week to move the government away from animal testing, but the agencies say that full implementation of the shift will require validation of the new approaches, a substantial effort that could consume many years.

Copyright Environment News Service (ENS) 2008. All rights reserved.