New Database Will Speed Development of Nonanimal Chemical Tests

We are exposed to hundreds of chemicals every day. Thus, assessing chemical safety is a huge public health and environmental issue. Regulators have historically assessed chemical safety with animal tests. Given the ethical and scientific issues with using animals, however, there has been a large push to replace animals with nonanimal tests. In order to organize data from methods that have already been developed and to speed the development of more methods the National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) has launched the Integrated Chemical Environment (ICE).

ICE is an open source web-based resource that integrates in vivo and in vitro data, high throughput screening data from the Tox21 consortium, and physicochemical property data from 10,000 chemicals. Making these data available to test method developers, companies, and other governments will speed the development of new methods and approaches to predict or test the safety of chemicals without animals. Furthermore, integrating data that compares the results of new methods with old methods or human responses, much of which have been generated over many years of validation studies, will also help speed the validation of new methods and combinations of methods.

Perhaps the most exciting feature of ICE is the incorporation of in vivo to in vitro extrapolation (IVIVE) information.  As the name implies, this feature would provide tools to assess safe doses of chemicals or drugs in a whole organism based on the doses that caused harm in an in vitro assay. NICETAM also has plans to link the IVIVE feature to biological pathways, which would be a valuable tool to predict the toxicity of chemical substances.

Just in time for the summer, ICE is undergoing its first version update in July (v1.1). One useful tool to be added in July is a workflow for the prediction of skin sensitization without animal testing. Skin sensitization refers to the potential of a chemical to cause an allergic skin reaction that can be quite painful to people, and to animals who are used in tests to assess it. The tool uses results of chemical prediction tools based on a chemical’s structure and other features.

Although this tool is fairly new, its utility is promising with respect to integrating data to answer hypotheses about chemical toxicity and to adding value to increasing test methods that do not use animals. What we can already assess with certainty is that the efforts of NICETAM, and the development of ICE, are great strides towards replacing the use of animals in chemical safety testing and developing reliable and scientifically valid methods to achieve that goal.

ICE can be found at https://ice.ntp.niehs.nih.gov.

Bell SM, Phillips J, Sedykh A, et al. An integrated chemical environment to support 21st-century toxicology. Environ Health Perspect. 2017;125(5):054501. doi: 10.1289/EHP1759.