The Toxicology in the 21st Century (Tox21) program is a federal collaboration among NIH’s NCATS and the National Toxicology Program at the National Institute of Environmental Health Sciences; the Environmental Protection Agency; and the Food and Drug Administration. Tox21 researchers aim to develop better toxicity assessment methods to quickly and efficiently test whether certain chemical compounds have the potential to disrupt processes in the human body that may lead to negative health effects. Read the latest news about this program below.
March 2019
NCATS Assay Recognized in Top Ten List of Innovative Scientific Achievements
NCATS developed a screening test to identify molecules that block the process of growing new blood vessels. With the test, NCATS scientists found both known and potential new anticancer drugs. The work earned a spot on the Society for Laboratory Automation and Screening’s top 10 innovative scientific achievements list for 2018.
October 2018
NCATS Scientists Prioritize Compounds to Advance Research on Mitochondrial Damage
NCATS scientists collaborated with other federal agencies to develop an approach that enables researchers to prioritize environmental chemicals according to their ability to disrupt mitochondrial activity.
March 2018
Tox21 Collaborators Release New Strategic Plan for Chemical Testing
On March 8, 2018, Tox21 program partners from NCATS, the National Toxicology Program at the National Institute of Environmental Health Sciences, the Environmental Protection Agency, and the Food and Drug Administration published a new strategic and operational plan to broaden the scope of their research activities to address new challenges. The collaborators are launching new cross-partner research projects to address five new areas of focus. The three-year projects each have support from a minimum of two Tox21 partners and will be reviewed annually by Tox21 leadership.
January 2016
NCATS Joins Challenge to Improve Toxicity Data
Tox21 seeks participants for the Tox Testing Challenge, with an award up to $1 million to improve the relevance and predictivity of data generated from automated chemical screening technology used for toxicity testing. The Challenge is cosponsored by the U.S. Environmental Protection Agency, NCATS, and the National Toxicology Program within the National Institute of Environmental Health Sciences.
January 2015
Tox21 Data Challenge 2014
NCATS announces the winners of the Tox21 Data Challenge 2014 (see below). Models from the seven winning teams all display good predictive power, achieving greater than 80 percent accuracy, and several models exceed 90 percent accuracy.
Population-Based in Vitro Hazard and Concentration–Response Assessment of Chemicals: The 1000 Genomes High-Throughput Screening Study
Tox21 collaborators also publish a study in the Jan. 13, 2015, issue of Environmental Health Perspectives to introduce a new way to measure human differences in sensitivity to chemicals. To establish safe levels of chemicals for human use, regulatory officials traditionally have used animal toxicology data to predict human responses to chemicals. This imperfect practice highlights a critical translational science and public health problem tackled by the Tox21 team, who used NCATS’ robotic screening capabilities to test the cells of more than 1,000 individuals with different genetic backgrounds for sensitivity to 179 chemicals.
July 2014
Profiling of the Tox21 10K Compound Library for Agonists and Antagonists of the Estrogen Receptor Alpha Signaling Pathway
Tox21 scientists publish the first results from screening the Tox21 10K library in the July 11, 2014, issue of Scientific Reports. The group developed an assay to test the effects of the approximately 10,000 chemicals on estrogen receptors, which are activated by the estrogen hormone and convey signals to the body that regulate reproductive functioning. Some chemicals may cause certain cancers or birth defects by mimicking estrogen and activating its receptors.
NCATS Announces Tox21 Data Challenge Winners
Tox21 experts also launch Data Challenge 2014, a crowdsourcing competition to develop computational models that can better predict chemical toxicity. Selected models will become part of the Tox21 program arsenal of tools that help researchers assess how various chemicals might disrupt biological processes in the human body and lead to negative health effects. Challenge participants will use data from nuclear receptor signaling and stress pathway assays (tests) run against Tox21’s 10K library to build models and look for structure-activity relationships.
2011
Collaborators publish details about the Tox21 program and its progress, including:
NCATS scientists developed a test to identify molecules that block the growth of new blood vessels. The test could be useful in cancer drug development. A scientific society 
NCATS scientists collaborated with other federal agencies to