American scientists could use robots, cells, and computational modeling to test chemicals and phase out the use of lab animals, thanks to a multi-agency pact announced this week.

The U.S. Environmental Protection Agency and the National Institutes of Health signed a memo of understanding to use new testing methods. The agencies announced the toxicity testing agreement Thursday. The details are published in the journal Science.

Two NIH institutes will work with the EPA to use the NIH Chemical Genomics Center's (NCGC) high-speed, automated screening robots to test compounds researchers suspect are toxic. The robots, created for the human genome project, could perform 10,000 cell screenings, using isolated molecular targets, each day.

NIH said the plan could generate data more relevant to humans; increase the number of chemicals tested; reduce time; and save money. Still, it could take years to validate the new testing methods.

"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," National Toxicology Program Associate Director John R. Bucher said in a news announcement. "This collaborative approach allows us to draw on our individual strengths and establishes a long-term, multiple U.S. federal agency commitment."

NTP is expected to contribute thousands of compounds for testing and lend its animal toxicology expertise, as well as a large database of the chemicals' effects on animals. That will form a basis of comparison for the new cell-based data.

The EPA's involvement is part of its ToxCast program, launched last year use advances in computers, genomics, and cellular biology to improve efficiency of the agency's chemical toxicity evaluation procedures.

George M. Gray, Ph.D., assistant administrator for EPA's Office of Research and Development, urged other federal agencies and private sector companies to join the effort.

The memo of understanding provides a framework for long-range planning called for in a 2007 National Research Council report on modernizing toxicity testing. The report urges toxicologists to collaborate and rely less on animal studies and more on in-vitro tests on human cells and cellular components.

A collective budget has not yet been established.