Name: Phenylmercuric Acetate
CAS No: (Acetato)phenylmercury [62-38-4]
BP: Phenylmercuric Acetate PhEur: Phenylmercuric Acetate USP-NF: Phenylmercuric Acetate
(Acetato-O)phenylmercury; acetoxyphenylmercury; phenylhydrargyri acetas; phenylmercury acetate; PMA; PMAC; PMAS.
(Acetato)phenylmercury [62-38-4]
C8H8HgO2 336.74
Phenylmercuric acetate is used as an alternative antimicrobial preservative to phenylmercuric borate or phenylmercuric nitrate in a limited range of cosmetics (in concentrations not exceeding 0.007% of mercury calculated as the metal) and pharmaceuticals. It may be used in preference to phenylmercuric nitrate owing to its greater solubility. Phenylmercuric acetate is also used as a spermicide; see Table I. See also Phenylmercuric Nitrate.
Phenylmercuric acetate occurs as a white to creamy white, odorless or almost odorless, crystalline powder or as small white prisms or leaflets.
See Table II.
Acidity/alkalinity pH 4 for a saturated aqueous solution at 208C. Antimicrobial activity Phenylmercuric acetate is a broad-spectrum antimicrobial preservative with slow bactericidal and fungicidal activity similar to phenylmercuric nitrate; see Phenylmercuric Nitrate. Dissociation constant pKa = 3.3 Melting point 1498C NIR spectra see Figure 1. Partition coefficients Mineral oil : water = 0.1 Solubility see Table III.
As for other phenylmercuric salts; see Phenylmercuric Nitrate. Phenylmercuric acetate should be stored in a well-closed container, protected from light, in a cool, dry place.
As for other phenylmercuric salts; see Phenylmercuric Nitrate. Incompatible with: halides; anionic emulsifying agents and suspending agents; tragacanth; starch; talc; sodium metabisulfite; sodium thiosulfate; disodium edetate; silicates; aluminum and other metals; amino acids; ammonia and ammonium salts; sulfur compounds; rubber; and some plastics. Phenylmercuric acetate is reported to be incompatible with cefuroxime and ceftazidime.(1)
Phenylmercuric acetate is readily formed by heating benzene with mercuric acetate.
Phenylmercuric acetate is mainly used as an antimicrobial preservative in topical pharmaceutical formulations. A number of adverse reactions to mercury-containing preservatives have been reported; see Phenylmercuric Nitrate. LD50 (chicken, oral): 60 mg/kg(2) LD50 (mouse, IP): 13 mg/kg LD50 (mouse, IV): 18 mg/kg LD50 (mouse, oral): 13 mg/kg LD50 (mouse, SC): 12 mg/kg LD50 (rat, oral): 41 mg/kg
Observe normal precautions appropriate to the circumstances and quantity of material handled. Phenylmercuric acetate may be irritant to the skin, eyes, and mucous membranes. Eye protection, gloves, and a respirator are recommended. Chronic exposure via any route can lead to central nervous system damage.
Included in the FDA Inactive Ingredients Database (ophthalmic ointments; topical emulsions/creams; vaginal emulsions/creams). Included in the Canadian List of Acceptable Non-medicinal Ingredients (ophthalmic, nasal and otic preparations up to 0.004%; there must be no other suitable alternative preservative available). Phenylmercuric acetate is no longer permitted to be used as a pesticide in the USA. Its use in cosmetic products in the USA is limited to eye area cosmetics at not more than 0.0065% provided that there is no other suitable available preservative. It is specifically prohibited in vaginal contraceptive drug products and antimicrobial diaper rash drug products in the USA. Phenylmercuric compounds are prohibited from use in cosmetic products in Canada. In Europe, use in cosmetic products is limited to eye makeup and eye makeup remover at concentrations not exceeding 0.007% mercury alone or in combination with other permitted mercurial compounds.(3) In France, a maximum concentration of 0.01% is permitted for use in pharmaceuticals. The use of mercurial compounds in cosmetics in Japan is limited to concentrated shampoo or cream at not more than 0.003% Hg and eye makeup at not more than 0.0065% Hg.
Phenylmercuric borate; phenylmercuric nitrate; thimerosal.
The EINECS number for phenylmercuric acetate is 200-532-5.