Крезол

Описание

Professions that involve dealing with the combustion of coal or wood may be exposed to higher levels of cresols than the general population. Environmental tobacco smoke is also a source of cresol exposure. Average cresol concentration may vary between the brand and type of cigarette in a 45-cubic meter chamber after six cigarettes had been smoked (ranged from 0.17 to 3.9 mg m3), although low levels of cresol can be detected in certain foods and tap water, and these do not constitute major sources of exposure for most population. Detectable levels of cresols have been reported in several consumer products including tealeaves, tomatoes, and ketchup as well as butter, oil, and various cheeses. Exposure to children occurs by the same routes that affect adults. Children are likely to be exposed to cresols through inhalation of contaminated air from automobile exhaust, waste incineration, and secondhand smoke.

Химические свойства

Cresol,a clear amber to red liquid, also known as cresylic acid, methylphenol, and tricresol,is a mixture of three isomers of cresol derived from coaltar and is used in making plastics, ore flotation, refining petroleum, and as a strong antiseptic. Orthocresol is a color less solid with a melting point of 30 °C(86 OF) that is soluble in alcohol,but only slightly soluble in water. It is used in making disinfectants and as a plasticizer. Metacresol is a colorless liquid used in the manufacture of photographic developers,printing inks, and paint removers.It is also used as a leather preservative.The least soluble isomer, paracresol, is a colorless solid and is used in the production of dyes and pharmaceuticals.

Использование

Cresol is used in disinfectants and fumigants,in the manufacture of synthetic resins, inphotographic developers and explosives.

Методы производства

Cresol may be obtained from coal tar or prepared synthetically by either sulfonation or oxidation of toluene.

Определение

A mixture of isomers obtained from coal tar or petroleum.

Общее описание

Colorless to yellow liquids with a tarry odor. Flash point 178°F. Insoluble in water. Density 8.7 lb / gal. Poisonous by ingestion and skin absorption and corrosive to skin.

Реакции воздуха и воды

Insoluble in water.

Профиль реактивности

Mixing CRESOL in equal molar portions with any of the following substances in a closed container caused the temperature and pressure to increase: chlorosulfonic acid, nitric acid, oleum, [NFPA 1991].

Опасность

Irritant, corrosive to skin and mucous membranes, absorbed via skin. Questionable carcinogen.

Угроза здоровью

The toxic actions of cresol are similar tothose of phenol. The para-isomer is somewhat more toxic than the other two isomers.The toxic symptoms are weakness, confu-sion, depression of the central nervous system, dyspnea, and respiratory failure. It isan irritant to the eyes and skin. Skin con-tact can cause burn and dermatitis. Chroniceffects are gastrointestinal disorders, nervousdisorders, tremor, confusion, skin eruptions,oliguria, jaundice, and liver damage. SkinLD50 values in rats for o-, m-, and p-phenolsare 620, 1100, and 750 mg/kg, respectively.
Dietz and Mulligan (1988a,b) have investigated the subchronic toxicity of meta- andpara-cresols in Sprague-Dawley rats after13 weeks of oral gavage. There was noadverse effects from a dose of 50 mg/kg/day.High dose levels of 150 mg/kg/day producedcentral nervous system depression and reduction of body weight gain. p-Cresol was foundto be hepatotoxic and nephrotoxic, inducinga mild anemic effect. The acute toxicity ofmethyl phenols did not show any relationshipto the number or position of methyl groupson the phenol nucleus. In an acute toxicitystudy on Daphnia magna, Devillers (1988)found cresols to be more toxic than phenol,xylenols, and trimethylphenols.

Пожароопасность

Combustible. POISONOUS GASES MAY BE PRODUCED IN FIRE. Flammable toxic vapors given off in a fire. Sealed closed containers can build up pressure if exposed to heat.

Химическая реактивность

Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.

Фармацевтические приложения

Cresol is used at 0.15-0.3% concentration as an antimicrobial preservative in intramuscular, intradermal, and subcutaneous injectable pharmaceutical formulations. It is also used as a preservative in some topical formulations and as a disinfectant. Cresol is not suitable as a preservative for preparations that are to be freeze-dried.

Безопасность

Reports of adverse reactions to cresol are generally associated with the use of either the bulk material or cresol-based disinfectants, which may contain up to 50% cresol, rather than for its use as a preservative. However, a recent case of cutaneous hypersensitivity reaction to the m-cresol component of an insulin formulation detected via intradermal and patch testing has been reported.
Cresol is similar to phenol although it is less caustic and toxic. However, cresol is sufficiently caustic to be unsuitable for skin and wound disinfection. In studies in rabbits, cresol was found to be metabolized and excreted primarily as the glucuronide.
A patient has survived ingestion of 12g of cresol though with severe adverse effects.
LD50 (mouse, oral): 0.76g/kg
LD50 (rabbit, skin): 2g/kg
LD50 (rat, oral): 1.45g/kg

Возможный контакт

Cresol is used as a disinfectant and fumigant; as an ore flotation agent, and as an intermediate in the manufacture of chemicals, dyes, plastics, and antioxidants. A mixture of isomers is generally used; the concentrations of the components are determined by the source of the cresol.

Экологическая судьба

It acts by disruption of the cell membrane by denaturation of proteins and enzymes of the cell.

хранилище

Cresol and aqueous cresol solutions darken in color with age and on exposure to air and light. Cresol should be stored in a well-closed container, protected from light, in a cool, dry place.

Перевозки

UN2076 Cresols, liquid, Hazard class: 6.1; Labels: 6.1-Poisonous materials, 8-Corrosive material. UN3455 Cresols, solid, Hazard class: 6.1; Labels: 6.1- Poisonous materials, 8-Corrosive material.

Несовместимости

Cresol has been reported to be incompatible with chlorpromazine. Antimicrobial activity is reduced in the presence of nonionic surfactants.

Утилизация отходов

Wastewaters may be subjected to biological treatment. Concentrations may be further reduced by ozone treatment. High concentration wastes may be destroyed in special waste incinerators.

Регуляторный статус

Included in the FDA Inactive Ingredients Database (IM, IV, intradermal, and SC injections). Included in parenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.