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Exploring ToxCast Data: Downloadable Data

The most recent ToxCast data is available in the invitroDBv3.3 database. The database was released in September 2020.  Data files from previously published ToxCast data releases are still available for download here. This page provides links to all relevant ToxCast chemical and assay data. 

ToxCast Data and Information

  • ToxCast & Tox21 Summary Files for invitroDBv3.3: Data for a single chemical endpoint pair for thousands of chemicals and assay endpoints for 20 variables such as the activity or hit call, activity concentrations, whether the chemical was tested in a specific assay, etc.
  • ToxCast & Tox21 Data Spreadsheet for invitroDBv3.3: A spreadsheet of EPA's analysis of the chemicals screened through ToxCast and the Tox21 collaboration which includes EPA's activity calls from the  screening of over 1,800 chemicals.
  • ToxCast Data Pipeline R Package (tcpl released with invitroDBv3.3): The R computer programming package used to process and model all EPA ToxCast and Tox21 chemical screening data. The files include the R programming package as well as documents that provide overviews of the data analysis pipeline used and the R package. Users will need experience with R to use these files.
  • ToxCast Database (invitroDBv3.3):  Database of EPA's analysis of chemicals screened through ToxCast assays, includes a MySQL database and the R package used to process the data.
  • ToxCast & Tox21 Concentration Response Plots for invitroDBv3.3: Concentration response plots for all of the ToxCast and Tox21 assays.
  • ToxCast & Tox21 Chemicals Distributed Structure-Searchable Toxicity Database (DSSTox files) for invitroDBv3.3: Chemical lists and information for 9,403 unique substances (DTXSIDs) and DSSTox standard chemical fields (chemical name; CASRN; structure; etc.). These chemicals have been evaluated through the ToxCast and Tox21 high-throughput screening efforts.
  • ToxCast & Tox21 High-Throughput Assay Documentation: ToxCast high-throughput assay documentation including descriptions, target information, study design information and quality statistics.
    • Assay Descriptions (work in progress) - Descriptions and guidelines for ToxCast assays in format outlined by the OECD Guidance Document 211 for  describing non-guideline in vitro test methods. The intent of GD 211 is to harmonize non-guideline, in vitro method descriptions to allow assessment of the relevance of the test method for biological responses of interest and the quality of the data produced. This document is organized by assay platform providers. You can also find descriptions for endocrine-related assays. It is a work in progress and will be updated as more assay information is available.  
    • Download Assay Information - Summary information and quality statistics for assays. 
    • Download ReadMe
  • Standard Laboratory Protocol for Tox21 Assays: Data describing the standard laboratory protocol for Tox21 assays including descriptions of Tox21 assays, protocol for all assays (reference, quality control, procedures and performance) and assay data. 
  • Collaborative Estrogen Receptor Activity Prediction Project Data: Data and supplemental files from CERAPP (A large-scale modeling project) which demonstrated the efficacy of using predictive computational models trained on high-throughput screening data to evaluate thousands of chemicals for estrogen-related activity. CERAPP combined multiple models developed in  collaboration with 17 groups in the United States and Europe to predict ER activity of a common set of 32,464 chemical structures. Quantitative structure-activity relationship models and docking approaches were employed, to build a total of 40 categorical and 8 continuous models for binding, agonist, and antagonist ER activity.
  • High-throughput Screening Data for Estrogen Receptor Model: Estrogen receptor model data from the manuscript titled Integrated Model of Chemical Perturbations of Biological Pathways Using 18 In Vitro High-throughput Screening Assays for the Estrogen Receptor (Judson et al) published in Toxicological Science.
  • High-throughput Screening Data for Androgen Receptor Model: Androgen receptor activity model data.
  • Previous ToxCast Data Releases: Data files from previously published ToxCast data releases. We DO NOT recommend using this data for new analyses, but are providing these files in case users need them for ongoing analyses.
  • Animal Toxicity Studies: Effects and Endpoints: The Toxicity Reference Database (ToxRefDB) provides results form across the thousands of animal toxicity studies including No Effect Level (NEL)/Lowest Effect Level (LEL) and/or No Observed Adverse Effect Level (NOAEL)/Lowest Observed Adverse Effect Level (LOAEL).

ToxCast Results and Processing

Descriptions of how data are processed through can be found on the Results Processing and Analysis.