nitromersol nitromersol 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. nitromersol names iupac name 5-methyl-2-nitro-7-oxa-8-mercurabicycloocta-1(6),2,4-triene other names metaphen; 6-methyl-3-nitrobenzoxamercurete; 4-nitro-5-hydroxymercuriorthocresol identifiers cas number 133-58-4 y 3d model (jsmol) interactive image chemspider 16739372 echa infocard 100.004.648 pubchem cid 16682935 unii ru6242gp15 comptox dashboard (epa) dtxsid9057638 inchi inchi=1s/c7h6no3.hg/c1-5-2-3-6(8(10)11)4-7(5)9;/h2-3,9h,1h3;/q;+1/p-1key: uehlxxjawywugi-uhfffaoysa-minchi=1/c7h6no3.hg/c1-5-2-3-6(8(10)11)4-7(5)9;/h2-3,9h,1h3;/q;+1/p-1/rc7h5hgno3/c1-4-2-3-5(9(10)11)6-7(4)12-8-6/h2-3h,1h3key: uehlxxjawywugi-itkdqslkat smiles cc1ccc(c2oc12)()=o properties chemical formula c7h5hgno3 molar mass 351.713 g·mol−1 hazards occupational safety and health (ohs/osh): main hazards moderately toxic except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references this compound is a confirmed animal carcinogen. it can emit toxic fumes of nox and mercury vapor when heated. 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. nitromersol can cause hypersensitivity reactions. it is still in use as a preservative for vaccines and antitoxins.