CC BY 4.0Yukie Baba2025-09-262025-09-262025-09-26https://2025.ifla.org/https://repository.ifla.org/handle/20.500.14598/6799Chirimen-bon, or Japanese crepe-paper books, gained international popularity during the late 19th and early 20th centuries and continue to attract interest today in antiquarian bookshops and libraries. However, it is not widely known that chirimen-bon often contain arsenic-based colorants. To protect library patrons and staff from arsenic poisoning, we are currently developing a database of old Japanese books that contain toxic substances. To enhance this database, we aim to collaborate with libraries worldwide, as chirimen-bon are found in libraries across the world, having diverse versions, each featuring unique coloring patterns. We invite you to join us in creating this database to foster a safer environment within libraries.enhttps://creativecommons.org/licenses/by/4.0/PreservationInternational cooperationHealth librariansRare books and manuscriptsEvents MaterialYukie Baba