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Chemical Assessment Clustering Engine (ChemACE)

The Chemical Assessment Clustering Engine (ChemACE) is designed to assist in the review and prioritization of large inventories of chemicals and to facilitate read across and data gap filling for untested substances.

Key characteristics of the tool include:

  • Clustering chemicals from a user defined input file into groups based on structural features and a reasonable presumption that toxicity may be influenced by such structural characteristics.
  • Identifying structural diversity in a large chemical inventory and instantly highlighting analogous clusters for potential read across.

The new ChemACE software is available for free from the EPA Office of Pollution Prevention and Toxics (OPPT). It is posted below as a downloadable software program and does not require a license for installation and use. Permission is granted for individuals to download and use the software on their personal and business computers.  Users may not alter, modify, merge, adapt, or prepare derivative works from the software.

Chemical Assessment Clustering Engine (ChemACE) Download(1 pg, 76 MB)

Additional Disclaimers:

  • Users should read the ChemACE User's Manual provided within the program to understand the proper use and limitations of ChemACE.
  • The user must apply professional judgement to determine the adequacy of any resulting clusters developed from ChemACE before read across and data gap filling approaches are applied.

The ChemACE User's Manual can be downloaded from the following link: ChemACE User Tutorial and is also available within the software programs “Help” button on the main data entry page. This file requires the Acrobat Reader.

U.S. EPA Technical Contacts:

Cathy Fehrenbacher, U.S. EPA
Office of Chemical Safety and Pollution Prevention
Risk Assessment Division
1200 Pennsylvania Ave., N.W.
Washington, DC 20460-0001
Phone: 202-564-8551