COVID-19 is an emerging, rapidly evolving situation.

Get the latest public health information from CDC and research information from NIH.

U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

National Toxicology Program

National Toxicology Program

UPDATE NewsletterUPDATE NewsletterApril 2021

The NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM)

By Catherine Sprankle

NICEATM releases ICE 3.3

On March 12, NICEATM released the version 3.3 update of the Integrated Chemical Environment (ICE). ICE provides data and tools to help develop, assess, and interpret chemical safety tests. This release adds two new tools, new features including expanded activity visualization, and new datasets to existing ICE resources.

New tools:

  • Curve Surfer: allows users to view and interact with concentration-response curves from curated high-throughput screening data.
  • Physiologically Based Pharmacokinetics (PBPK) tool: this tool, based on the the U.S. Environmental Protection Agency (EPA) httk package, allows users to generate predictions of tissue-specific chemical concentration profiles following a dosing event.

Updates to existing tools:

  • Search tool: users can get detailed visualization of query results.
  • In Vitro to In Vivo Extrapolation (IVIVE) tool: users can now upload their own in vivo data to overlay on the results.
  • Chemical Characterization: new visualizations include bioactivity principal component analysis plots and Consumer Use Explorer, which allows users to view chemical use categories from the EPA Consumer Products Database (CPDat).

New data:

  • Cancer data from multiple sources, including detailed data from NTP two-year cancer bioassays and in vivo and in vitro genotoxicity studies.
  • Developmental and reproductive toxicity in vivo bioassays from the EPA’s Toxicity Reference Database (ToxRefDB).
  • Updated in vivo human predictive patch test data set for skin sensitization characterization compiled by NICEATM and the German Federal Institute for Risk Assessment (BfR).

DNTP postdoctoral fellow wins SOT specialty section Young Investigator award

The Society of Toxicology (SOT) Computational Toxicology Specialty Section selected DNTP/NICEATM scientist Shagun Krishna as the recipient of this year’s Yves Alarie Diversity Award for Trainees and Young Investigators. This award recognizes a young investigator from an under-represented group who is working in the field of computational toxicology. The award was presented at the specialty section’s virtual reception on March 16.

Krishna is a postdoctoral fellow at the National Institute of Environmental Health Sciences. Her mentor is Acting NICEATM Director Nicole Kleinstreuer. The current focus of Krishna’s research is developing informatics approaches to identifying potentially cardiotoxic substances.

NICEATM paper named Paper of the Year by SOT specialty section

Neepa Choksi, Principal Toxicologist at ILS (contractor supporting NICEATM), is first author of the 2021 SOT Ocular Toxicology Specialty Section Paper of the Year. The paper describes validation of OptiSafe, a non-animal method to assess eye irritation hazard. The award was presented at the specialty section’s virtual reception on March 15.

Choksi et al. 2020. Validation of the OptiSafe™ eye irritation test. Cutan Ocul Toxicol 39(3):180-192.

Recent publications

  • Because specific positive control materials are often written into testing standards for in vitro assays, selection of appropriate positive control materials can aid in ensuring the long-term relevance and usability of these standards. A recent publication in the journal ALTEX describes characteristics that should be considered when selecting a positive control material for an in vitro assay. Acting NICEATM Director Kleinstreuer is a coauthor of the paper.
    Petersen et al. 2021. Characteristics to consider when selecting a positive control material for an in vitro assay. ALTEX.
  • Estimates of dermal absorption used in dermal toxicity hazard assessments are currently derived using both in vitro and in vivo data. NICEATM and EPA retrospectively evaluated agrochemical formulations to assess the feasibility of using in vitro data alone for these estimates. The comparisons presented support potentially using in vitro data alone to derive these estimates for human health risk assessment of pesticides.
    Allen et al. 2021. Retrospective analysis of dermal absorption triple pack data. ALTEX.
  • Acting NICEATM Director Kleinstreuer also coauthored two recent workshop reports:

Back to Top

The Update Newsletter is produced by NTP Office of Policy, Review, and Outreach. The text is not copyrighted and can be reprinted without permission. If you use parts of the Update Newsletter in your publication, we ask that you provide us with a copy for our records. We welcome your comments and suggestions.

Director of Office of Policy, Review, and Outreach and Editor-in-Chief: Mary Wolfe | Managing Editor: Anna Lee Mosley