NIEHS Leads International Guideline Update on Nonanimal Testing

NIEHS scientists and collaborators recently played a lead role in updating an international guideline designed to expand the use of nonanimal approaches in chemical safety testing. The milestone update marks the first time a nonanimal method to predict the degree of a chemical’s toxic effects has gained international acceptance.

The updated guideline describes testing strategies known as defined approaches that combine multiple types of nonanimal testing methods to help predict whether chemicals in cosmetics, pesticides, and other consumer products are skin sensitizers before they are marketed to consumers. Chemicals that can cause allergic skin reactions, such as rashes, are called skin sensitizers.

The updated “Defined Approaches on Skin Sensitisation” guideline was published June 25 by the Organisation for Economic Co-operation and Development (OECD), a 38-country trade organization. Scientists in the National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) led development of the updated guideline and the groundbreaking 2021 guideline, which was the first to outline approaches to replace animal use for regulatory characterization of skin sensitizers.

“This update will make it easier for more regulated companies to use these defined approaches,” said Helena Hogberg, Ph.D., acting director of NICEATM. “It will also allow data from defined approaches to be used in a broader range of regulatory contexts.”