Nitromersol (metaphen) is a mercury-containing organic compound that is primarily used as an antiseptic and disinfectant.

It is a brown-yellow solid that has no odor or taste, does not irritate the skin or mucous membranes, and has no impact on rubber or metallic instruments, including surgical and dental tools.

[1] This compound is a confirmed animal carcinogen.

It can emit toxic fumes of NOx and mercury vapor when heated.

[2] In 1998, use of nitromersol (and other mercury-containing products) as OTC first-aid antiseptics and products for diaper rash and vaginal contraceptives was disallowed by the FDA.