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Annual Report for Fiscal Year 2018

Annual Report for Fiscal Year 2018

Federal Partners Put Tox21 Plan into Action

Federal partners gathered at NIEHS May 15–16, 2018, to discuss the implementation of the new Toxicology in the 21st Century (Tox21) strategic plan.

For more than a decade, Tox21 has used automation and cell-based tests to rapidly measure the toxicity of chemicals with a mechanized, high-throughput approach.

Under the new strategic plan, NTP Tox21 activities will continue to refine prediction of chemical toxicity to humans:
  • Enhanced methods for testing genetic toxicity will assess whether chemicals are toxic to thousands of genes in specific types of cells.
  • Increased use of stem cells will support study of the effects of chemicals on developmental processes.
  • New computational models will help to better predict the relationship between external chemical doses and resulting chemical concentrations in tissues.
  • The Tox21 consortium will test toxicity in biological systems more complex than single cell types.
  • Some testing will be done in alternative species like zebrafish.

Tox21 is exploring the use of 3-D cellular models or tissue chip systems that model the structure and function of different organs, or even how these organs interact. Such approaches will not be as fast as current Tox21 assays, so testing thousands of compounds will have to be carefully strategized.

The Tox21 consortium will continue to refine its high-throughput methods and is also developing performance standards to establish confidence in novel approaches.

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