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Your Environment. Your Health.


The Tox21 Program (Toxicology in the 21st Century) is an ongoing collaboration among federal agencies to characterize the potential toxicity of chemicals using cells and isolated molecular targets instead of laboratory animals.

Tox21 leverages the experimental toxicology expertise of the National Toxicology Program, headquartered at the NIEHS; the high-throughput technology of the NIH Chemical Genomics Center, part of the National Center for Advancing Translational Sciences; the computational capabilities of the Environmental Protection Agency and the expertise of the Food and Drug Administration, to test more than 10,000 drugs and chemical using biological assays.

Please see the Tox 21 fact sheet for more information.

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