Guidance on new non-animal test methods
The Lush Prize has welcomed new advice on the use of non-animal test methods for chemical testing.
REACH (The Registration, Evaluation and Authorisation of Chemicals) is an EU law introduced in 2007 which requires the safety (toxicity) testing of all new and existing chemicals, under a series of different deadlines. Despite REACH requiring the use of non-animal methods whenever possible, animal testing is still used and millions of animals are expected to suffer and die until the final deadline in 2018. Just one test can use almost 1000 animals and in 2014 ECHA confirmed that almost 5000 animal tests had been carried out under REACH so far. For more information, see here).
The authority responsible for overseeing REACH is the European Chemicals Agency (or ECHA). It has published new guidance on the use of two non-animal test methods for skin sensitisation. Both tests have recently been accepted for regulatory use by the OECD (The Organisation for Economic Co-operation and Development) and a third test is also under discussion at OECD and is currently available as a draft guideline. The OECD Test Guidelines are a collection of internationally agreed test methods, used to determine the safety of chemicals and chemical preparations, including pesticides and industrial chemicals.
The two OECD approved tests are as follows:
- The Direct Peptide Reactivity Assay (DPRA) – a test which measures the potential of a chemical to react with skin proteins and initiate the first stage of skin sensitisation involving redness and swelling
- The Keratinosens Test – a method that assesses the second stage in the skin sensitisation process. The test involves administering a test chemical to human skin cells (keratinocytes) and measuring increases in skin sensitisation related to genetic activity
The third method is the Human Cell Line Activation Test, or h-CLAT, a further ‘in vitro’ test which measures activation by a substance of the skin’s dendritic cells, the third key stage in skin sensitisation which involves the immune system. This method is currently in its draft stage at OECD and has yet to be finally approved.
For companies who wish to market new substances for use in cosmetics and other products, they must meet REACH requirements. The above methods can be used together in an integrated, non-animal testing approach to register substances for the next REACH deadline in 2018.
ECHA advises companies that correct use of a combination of these tests can replace animal tests. The main animal (in-vivo) test still used in skin sensitisation testing is the Local Lymph Node Assay (LLNA) which involves groups of mice being repeatedly dosed with increasing concentrations of a chemical over six days. This is administered to the ear, to check for redness and swelling, as well as other chemicals injected through their tail veins, and the animals are then killed and examined for signs of toxicity. Other invasive and cruel tests involving guinea pigs may also be used.