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ToxCast Data Generation: Assay Platform Sources, Descriptions, and Protocols

Assay Descriptions

  • CompTox Chemicals Dashboard  provides short descriptions of the assays and a summary of hit calls. You can click on details for more information about each assay. 
  • Assay Summary Information provides summary information and quality statistics on each of the ToxCast assays. The summary information includes measured readouts and analyzed results.
  • ToxCast Assay Descriptions provides descriptions and guidelines for ToxCast assays in a format outlined by the OECD Guidance Document 211 for  describing non-guideline in vitro test methods. This document is a work in progress and updated as more decriptors are added. 

ToxCast Assay Platform

Assay Platform Sources

Download ToxCast Assay Platform Source Description document to learn more about the platform sources of the ToxCast assays.

EPA’s ToxCast Assay Annotation Data User Guide documents the annotations to assist ToxCast data users in understanding how to use the annotation terms within the ToxCast screening data. It explains annotation concepts and terminologies.

Assay Protocols


EPA’s standard laboratory protocols for Tox21 assays including descriptions, protocols (reference, quality control, procedures and performance), and assay data.

National Institutes of Health Tox21 assay descriptions and protocols are also available on the National Center for Biotechnology Information’s PubChem Bioassay database.