News

Published: 03 August 2023

...and the number may still increase

The chemicals regulation REACH (Registration, Evaluation, Authorization, and Restriction of Chemicals) stipulates manufacturers and importers of chemicals to register them and to evaluate their properties, in particular their toxicity. It is no secret that animal experiments are usually conducted for this purpose. But how many animals actually die due to the regulation was not official until now. The Center for Alternatives to Animal Testing (CAAT) has now published a study that reveals the true extent of animal use.

REACH came into force in 2007 and affects a wide range of chemicals that are manufactured in or imported into the EU in quantities of one tonne or more per year. The regulation requires a comprehensive safety assessment of the chemicals, which is usually done by exposing animals to the chemical. In various test sequences, the toxicity of the substance is assessed by administering it to the animals and their offspring. For example, the substances to be tested are administered daily for up to 90 days by gavage into the stomach of rodents, with the concentration of the chemical being chosen in a way that toxic effects are to be expected. The animals are observed, killed, and then examined. How many animals had to suffer and die for REACH in such tests and similar ones was previously unknown.

A current study by the Center for Alternatives to Animal Testing (CAAT) is presenting figures for three of the test categories required by REACH for the first time (1). These categories include reproductive toxicity testing, developmental toxicity testing, and repeated dose toxicity testing (described above). By the end of last year, 2.9 million animals were used across the EU in these 3 categories alone. In addition, 1.3 million animals are being used in currently ongoing experiments. With 4.2 million animals in these 3 categories, the number already exceeds the total r of 2.6 million animals expected by the European Commission in 2004 for all REACH tests. A large number of tests in the study have so far not been taken into account. This applies, for example, to acute toxicity, genotoxicity, and ecotoxicity tests, so that the actual number of animals used to implement REACH is even higher.

The figures that have now been published are way more frightening given that there is a whole series of non-animal safety testing methods, like organoids derived from human cells, that allow assessment of the toxicity. It was shown recently that so-called organ chips containing human liver cells are more suitable for determining the liver toxicity of substances than animal experiments (2) and it is expected that such non-animal test methods will replace animal experiments for safety assessment (3).

Powerful non-animal methods obviously already exist. However, many of these procedures are not yet acknowledged for REACH. Only read-across procedures are accepted as a so-called alternative to animal testing. With read-across, toxicity data from already well-studied chemical compounds are transferred and compared to structurally similar substances. The CAAT study shows that although the read-across approach is often applied for, the European Chemicals Agency (ECHA) accepts it in roughly a quarter of the cases.

The fact that the number of animals used in REACH is so high, although the REACH regulation stipulates that animal experiments may only be carried out as a "last resort" (for example when no other test methods are available) shows once again how slowly the authorities react to the current state of science. A revision of the REACH regulation is also being discussed in the EU, for which a draft is expected by the end of the year. The concern is that these changes will lead to a further increase in animal consumption (4).

Regarding the shocking numbers that have now been published, we demand that existing animal-free methods for assessing chemical safety shall be approved and used immediately, and that the development of further animal-free methods shall finally be extensively funded.