Phenylmercuric borate

The CAS Registry Number, chemical name and synonyms all refer to phenylmercuric borate alone, rather than the compound. The name phenylmercuric borate and the synonyms may, however, be applied to the PhEur 2005 material, which is a compound or a mixture of compounds, see Section 4. Unique CAS Registry Numbers for phenylmercuric borate and the compounds are as follows  

The PhEur 2005 material is a compound consisting of equimolecular proportions of phenylmercuric hydroxide and phenylmercuric orthoborate (Ci2Hi3BHg204) or of the dehydrated form (metaborate, Ci2HuBHg203), or a mixture of the two compounds. 

Phenylmercuric borate is used as an alternative antimicrobial preservative to phenylmercuric acetate or phenylmercuric nitrate. It is more soluble than phenylmercuric nitrate and has also been reported to be less irritant than either phenylmercuric acetate or phenylmercuric nitrate. See Table I. 

Phenylmercuric borate occurs as colorless, shiny flakes or as a white or slightly yellow, odorless, crystalline powder. 

Antimicrobial activity phenylmercuric borate is a broad-spectrum antimicrobial preservative with slow bactericidal and fungicidal activity similar to that of phenylmercuric nitrate see Phenylmercuric Nitrate. 

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C Hs 71-43-2) see Budipine Clotrimazole Fexofenadine hydrochloride Ibuprofen Phenylmercuric borate ... 

CxH Hg02, 62-38-4) see Phenylmcrcuric borate phenylmercuric hydroxide (C H HgO 100-57-2) see Phenylmercuric borate JV-[(phenylmethoxy)carbonylJ-DL-homocysteine acetate (ester)... 

There have been two reports of patients scheduled for tonometry who developed periorbital dermatitis following the topical instillation of local anesthetic eye drops (4). The first patient reacted strongly positive on patch testing to Thilorbin AT (oxybuprocaine, fluorescein, phenylmercuric borate, polysorbate 20, mannitol) and also to oxybuprocaine alone. The second reacted to Conjucain EDO (oxybuprocaine, sorbitol, sodium hydroxide) and to oxybuprocaine alone. The authors believed these to be the only described cases of a delayed hjrpersensitivity reaction to oxybuprocaine, an ester local anesthetic commonly used for topical anesthesia in the eye. 

Phenylmercuric acetate is used as an alternative antimicrobial preservative to phenylmercuric borate or phenylmercuric nitrate in cosmetics (in concentrations not exceeeding 0.0065% of mercury calculated as the metal) and pharmaceuticals. It may be used in preference to phenylmercuric nitrate owing to its greater solubility. 

Phenylmercuric borate should be stored in a well-closed container, protected from light, in a cool, dry place. 

Phenylmercuric borate may be prepared by heating mercuric borate with benzene or by evaporating to dryness, under vacuum, an alcoholic solution containing equimolar proportions of phenylmercuric hydroxide and boric acid. 

Peters-Haefeli L, Michod JJ, Aelhg A, et al. Urinary excretion of mercury after the use of an antiseptic soap containing 0.04% of phenylmercuric borate [in French]. Schweiz Med Wochenschr 1976 106(6) 171-178. 

Phenylmercuric borate 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. 

Systemic absorption has been reported following regular use of a hand disinfectant soap containing 0.04% phenylmercuric borate, resulting in an increase in the estimated total daily body load of mercury from 30-100 pg per 24 hours. ... 

Observe normal precautions appropriate to the circumstances and quantity of material handled. Phenylmercuric borate may be irritant to the skin, eyes, and mucous membranes. Eye protection, gloves, and a respirator are recommended. In tbe UK, the occupational exposure limit for mercury-containing compounds, calculated as mercury, is 0.01 mg/m long-term (8-hour TWA) and 0.03 mg/m short-term. ... 

Phenylmercuric salts are active over a wide pH range against bacteria and fungi and are usually used in neutral to alkaline solutions, although they have also been used effectively at slightly acid pH see Section 10. In acidic formulations, phenylmercuric nitrate may be preferred to phenylmercuric acetate or phenylmercuric borate as it does not precipitate. 

Phenylmercuric acetate phenylmercuric borate phenylmercuric nitrate. 

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