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Environmental Modeling Community of Practice

Acute-to-Chronic Estimation (ACE) with Time-Concentration-Effect Models Software

ICE and ACE were developed by the U.S. EPA in collaboration with other federal agencies, industry, and universities to address data gaps in species sensitivity and reduce reliance on uncertainty factors in ecological risk assessment.

The Acute-to-Chronic Estimation (ACE) with Time-Concentration-Effect Models software allows prediction of chronic toxicity from acute toxicity datasets. ACE uses linear regression and accelerated life testing to predict no-effect and low-effect concentrations for chronic mortality.

Current Version: 2.0
Release Date: December 2003
Development Status: General Release
Development Information: Release Notes - changes and known deficiencies
Operating System: Win 9x, NT, 2000, XP
Development Language: Visual Basic, Fortran
Intended Audience: Scientist/Biologist
Key Words: acute, chronic, toxicity, concentration, exposure
Related Web Sites: Web-ICE Model Page
EPA National Health and Environmental Effects Research Laboratory (NHEERL)
Text Files (ASCII Format)
File Name File Description
ABSTRACT.TXT Summary of functions, theory, and applicability.
README.TXT Important installation and usage information.
Download Files
File Type /
File Name /
Format /
File Description
Install /
Install_ACE.EXE /
Self-extracting Executable /
4.3 MB
Setup file for version 2.0 of the ACE system. See README.TXT for important installation instructions.
Document /
ACE User's Manual /
Self-extracting Zip /
0.3 MB
Acute - to - Chronic Estimation (ACE) with Time - Concentration - Effect Models User Manual (EPA/600/R-03/107), in Adobe Acrobat format.