Nitromersol (metaphen) is a mercury-containing organic compound that is primarily used as an antiseptic and disinfectant. It has no odor or taste and is stored as a brown-yellow granules or powder. Nitromersol does not irritate the skin or mucous membranes and has no impact on rubber or metallic instruments, including surgical and dental tools.
This compound is a confirmed animal carcinogen. It can emit toxic fumes of NOx and mercury when destroyed by heat. In 1998, use of nitromersol (and other mercury-containing products) as OTC first-aid antiseptics and products for diaper rash and vaginal contraceptives, was outlawed by the FDA. Nitromersol can cause hypersensitivity reactions, but it is still in use as a preservative for vaccines and antitoxins.