Horizon Magazine · Health

AI and new methods aim to replace animal testing for chemical safety

Researchers are developing advanced methods, including AI and cell-based tests, to replace animal testing for chemical safety assessments in the EU, driven by ethical concerns, cost, and questions about the human relevance of animal test results.

Around 150,000 animals, primarily rats and mice, are used annually in the EU for testing the safety of everyday chemicals. Animal welfare advocates have raised concerns, and the reliability of animal test results for humans is questioned. Researchers are creating more accurate and less invasive testing methods, building on the EU's ban on animal testing for cosmetics.

The EU regulation REACH mandates that companies must register and prove the safety of substances to access the European market. This regulation also commits Europe to the 'three Rs': replacing animal tests where possible, reducing animal numbers, and refining procedures to minimize suffering. Three linked research initiatives, funded by the EU's €60 million ASPIS cluster, are working since 2021 to replace animal testing with non-animal approaches, including in vitro and AI-driven methods.

EU law prioritizes animal use only as a last resort. Reducing animal testing also benefits human safety, as Professor Mathieu Vinken of Vrije Universiteit Brussel notes that only about 50% of current animal tests are representative for humans. The ONTOX initiative within ASPIS investigates how repeated chemical exposure harms the kidney, liver, and brain.

Animal tests, especially chronic toxicity tests involving hundreds of animals and long-term exposure assessments, are expensive and time-consuming. Traditional methods struggle to predict long-term toxicity and diseases that develop over decades, a challenge exacerbated by rodents' shorter lifespans. AI and organ-on-a-chip technology, using human cells to mimic organ responses, are being developed to interpret results for human organs.

The research has garnered interest from international bodies like the OECD. This work follows a broader trend in Europe, exemplified by the EU's progressive phase-out and 2013 marketing ban on animal testing for cosmetics, which spurred the development of non-animal methods like reconstructed human skin models.

Professor John Colbourne's PrecisionTox initiative compares responses of five model organisms and human cells to approximately 200 chemicals. By studying species like fruit flies, roundworms, water fleas, zebrafish, and frog embryos, researchers identify how chemicals interfere with conserved biological mechanisms essential for life and health across species.

The RISK-HUNT3R initiative within ASPIS integrates results from non-animal tests with real-world exposure data to assess chemical risks. This strategy, tested on 60 chemicals, aims to provide reliable safety assessments for regulators. The overall goal is to fundamentally rethink chemical safety assessment by combining human-relevant biology, exposure data, and computational tools.

While completely abandoning animal testing is not yet feasible, significant progress is being made in refining procedures and reducing animal use. AI is expected to play a crucial role in substantially decreasing animal testing in the future.

AI-samenvatting op basis van de bron.