Precautions
One study in mice demonstrated dose-related carcinogenic potential at several different organ sites[3][4]. The Food and Drug Administration in the US has determined that gentian violet has not been shown by adequate scientific data to be safe for use in animal feed. Use of gentian violet in animal feed causes the feed to be adulterated and is a violation of the Federal Food, Drug, and Cosmetic Act in the US. On June 28, 2007, the US food and Drug Administration issued an "import alert" on farm raised seafood from China because unapproved antimicrobials, including gentian violet, had been consistently found in the products. The FDA report states:
"Like MG [malachite green], CV [crystal violet] is readily absorbed into fish tissue from water exposure and is reduced metabolically by fish to the leuco moiety, leucocrystal violet (LCV). Several studies by the National Toxicology Program reported that the carcinogenic and mutagenic effects of crystal violet in rodents. It has also been linked to increased risk of human bladder cancer. The leuco form induces renal, hepatic and lung tumor in mice."[5]
Gentian violet's worst common side effect is staining skin and cloth, but it can easily be washed off of skin with a solution of bleach and water. However, if used on ulcerations or open wounds it can cause tattooing. It is generally considered safe for use on children and breastfeeding mothers. It has even been applied to the mouth and lips of premature infants, and has a long history of safe use. Many have recommended it for thrush on the nipple, and La Leche League lists gentian violet as a possible alternative.[6] However, in large quantities, gentian violet may lead to ulceration of a baby's mouth and throat and is linked with mouth cancer.[7] Gentian violet has also been linked to cancer in the digestive tract of other animals[8]. |