Chemical Testing Using New Approach Methodologies Nams

Chemical Testing Using New Approach Methodologies (NAMs)

Reducing Animal Use in Carcinogenicity Testing

Carcinogenicity to rats and mice is evaluated for substances to which humans are exposed, including pharmaceuticals, agrochemicals, and industrial chemicals. For pharmaceuticals, recent efforts to reduce animal use in long-term studies include an addendum to the International Council for Harmonisation (ICH) guideline S1B(R1) that prioritizes short-term studies in transgenic mice and recommends assessing the weight of evidence available to first determine whether a long-term study in rats would add value. For other sectors, an expert group of the Organisation for Economic Cooperation and Development (OECD) is developing an Integrated Approach to the Testing and Assessment (IATA) of non-genotoxic carcinogens based on common hallmarks of cancers and on key characteristics of carcinogens. Within current regulations, animal use could be reduced by evaluating toxicokinetics in main study animals with microsampling methods, by including only one negative control group, and by genotyping transgenic mice instead of using positive control groups in each study.

Nordic Workshop on New Approach Methodologies (NAMs)

Available online: https://pub.norden.org/temanord2022-526/ New Approach Methodologies (NAMs) are an emerging tool in toxicology for performing chemical risk assessment. NAMs reduce animal testing while increasing robustness, throughput and providing a mechanistic understanding of chemical modes-of-actions, in accordance with the Next Generation Risk Assessment principles. The workshop’s objective was to increase risk assessors’ understanding of the data produced by NAMs and their ability to use it for regulatory actions under REACH and CLP. It aimed to highlight the main challenges for NAMs, discuss possible advancements in using NAMs, and increase knowledge and competence within the relevant Nordic authorities. It also served to facilitate discussions about the obstacles to implementing NAMs in regulatory processes, and to identify strategies (including omics approaches) for increasing their use in read-across and grouping processes.