-Useful for safety testing of cosmetics without utilizing experimental animals-
An eye irritation test method to evaluate safety of cosmetic raw materials is newly included in the unified testing method defined by the Organization for Economic Co-operation and Development (OECD). In this test method, by means of exposing the chemical substance to culture model that simulates the corneal structure, it is possible to determine the irritant properties of chemical substances by measuring changes in electrical resistance for just 3 minutes. In future it is expected to be used for the development of highly safe cosmetics etc. as a simple and quick safety test method that does not utilize experimental animals.
The joint collaboration of National Agriculture and Food Research Organization (President: Dr. Kazuo KYUMA), The National Institute of Health Sciences (NIHS) (Director: Dr. Haruhiro OKUDA) and KANTO CHEMICAL CO., INC. (CEO: Manabu NOZAWA) has developed a "Vitrigel-Eye Irritancy Test (Vitrigel-EIT) method". This test method which is used to determine the eye irritation potential of chemicals without using animals is listed/published in the unified test method (OECD Test Guideline) defined by the Organization for Economic Co-operation and Development (OECD), which is an international official method.
When developing cosmetics and medicines, it is necessary to confirm the safety of the chemical substances included as components, to the people. Many of these "safety tests" have been conducted using animals. However, in recent years development of alternative animal experiments using non-animal human cells has been promoted worldwide.
Collagen fibers, which surround cells in vivo, play a role as a scaffold for cells that constitute tissues. At NARO, we are focusing on the scaffolds that hold cells in in vivo tissue when regenerating multicellular tissue and promote the development of products using "collagen vitrigel", a new material of high-density collagen fibrillar network comparable to this scaffold. In 2013, we developed a highly sensitive safety test method of chemical substances for the eyes (Vitrigel-EIT method), by means of a culture model of human corneal epithelium constructed using this material. Special features of this method are it is quick, sensitive and highly reproducible test results can be obtained without using experimental animals.
Three domestic facilities such as Hatano Research Institute, Food and Drug Safety Center (FDSC), Bozo Research Center, Inc., and Daicel Corporation conducted validation study of the developed Vitrigel-EIT method and verified its validity. This test method was included in the OECD Test Guidelines in June 2019 after a third-party review by experts. In the future, it is expected to be used as a simple and quick safety test method without using experimental animals, thereby enabling the development of highly safe cosmetics etc. domestically and internationally.
OECD (2019), TG 494: Vitrigel-Eye Irritancy Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage, OECD Guidelines for the Testing of Chemicals, Section 4, OECD Publishing, Paris, https://doi.org/10.1787/9f20068a-en.