Carcinogenicity of gentian violet, leucogentian violet, malachite green, leucomalachite green, and CI Direct Blue 218

In February–March, 2021, a Working Group of 11 scientists from eight countries met remotely at the invitation of the International Agency for Research on Cancer (IARC) to finalise their evaluation of the carcinogenicity of five agents used as dyes and reagents, and for their antibacterial and antifungal properties. For all these agents, the evidence regarding cancer in humans was “inadequate”, as no studies were available. Data from humans on exposure, absorption, distribution, metabolism, or excretion and on mechanisms were sparse. Gentian violet, leucomalachite green, and CI Direct Blue 218 were classified as “possibly carcinogenic to humans” (Group 2B) on the basis of “sufficient” evidence of carcinogenicity in experimental animals. Leucogentian violet and malachite green were evaluated as “not classifiable as to its carcinogenicity in humans” (Group 3). These assessments will be published in Volume 129 of the IARC Monographs. 1 International Agency for Research on Cancer. Volume 129: Gentian violet, leucogentian violet, malachite green, leucomalachite green, and CI Direct Blue 218. IARC Working Group. Lyon, France; Feb 25–March 5, 2021. IARC Monogr Identif Carcinog Hazards Hum (in press). Google Scholar