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Tox21 Work Groups


  • Identify key toxicity pathways/assays (with a focus on human cells) and prioritize assays for use at National Center for Advancing Translational Sciences (NCATS)
  • Identify methods for incorporating hepatic metabolism into in vitro assays
  • Consider approaches for evaluating compound, pathway, and cell-to-cell interactions


  • Establish library of >10,000 compounds with known structures for testing at the NCATS
  • Establish procedures for determining the identity, purity, and stability of each compound
  • Future, establish a library of water soluble compounds for testing at the NCATS
  • Future, establish a library of mixtures for testing at the NCATS

Bioinformatics Group

  • Evaluate response within and across assays/endpoints
  • Evaluate patterns of response and relationship to adverse health outcomes in experimental animals and humans
  • Make all data publicly accessible (CEBS, PubChem, ACToR)

Targeted Testing Group

  • Design studies to evaluate the relevance of prediction models and prioritization schemes developed from Tox21 data