Cresols disinfectants

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. ... 

If the third substance dissolves in both liquids (and the solubility in each of the liquids is of the same order), the mutual solubility of the liquids will be increased and an upper C.S.T. will be lowered, as is the case when succinic acid or sodium oleate is added to the phenol - water system. A 0 083 molar solution of sodium oleate lowers the C.S.T. by 56 -7° this large effect has been applied industrially in the preparation of the disinfectant sold under the name of Lysol. Mixtures of tar acids (phenol cresols) do not mix completely with water at the ordinary temperature, but the addition of a small amount of soap ( = sodium oleate) lowers the miscibility temperature so that Lysol exists as a clear liquid at the ordinary temperature. 

Cresylic acid is mainly used as degreasing agent and as a disinfectant of a stabilized emulsion in a soap solution. Cresols are used as flotation agents and as wire enamel solvents. Tricresyl phosphates are produced from a mixture of cresols and phosphorous oxychloride. The esters are plasticizers for vinyl chloride polymers. They are also gasoline additives for reducing carbon deposits in the combustion chamber. 

Many of the phenols which are used in household and other commercial disinfectant products are produeed from the tar obtained by distillation of coal or more recently petroleum. They are known as the tar acids. These phenols are separated by fractional distillation according to their boiling point range into phenol, cresols, xylenols and high boiling point tar acids. As the boiling point increases the properties of the products alter as shown ... 

Clear soluble fluids. Cresol is a mixture of o-, m- and p-methyl phenol (Fig. 10.7A). Because of its poor solubility, it is solubilized with a soap prepared fiom linseed oil and potassium hydroxide. It forms a clear solution on dilution. This preparation, known as Lysol (Cresol and Soap Solution BP 1968) has been widely used as a general purpose disinfectant but has largely been superseded by less irritant phenolies. 

Many derivatives of phenol are now made by a synthetic process. Homologous series of substituted derivatives have been prepared and tested for antimicrobial activity. A combination of alkyl substitution and halogenation has produced useful derivatives including clorinated phenols which are constituents of a number of proprietary disinfectants. Two ofthe most widely used derivatives are/ -chloro-m-cresol (4-chloro-3-methylphenol, chlorocresol, Fig. 10.7C) which is mostly employed as a preservative at a concentration of 0.1%, and / -chloro-m-xylenol (4-chloro-3,5-dimethylphenol, chloroxylenol. Fig. 10.7C) which is used for skin disinfection, although less than formerly. Chloroxylenol is sparingly soluble in water and must be solubihzed, for example in a suitable soap solution in conjunction with terpineol or pine oil. Its antimicrobial capacity is weak and is reduced by the presence of organic matter. 

Cresols are natural products that are present in many foods and in animal and human urine. They are also present in wood and tobacco smoke, crude oil, and coal tar. In addition, cresols also are man-made and used as disinfectants and deodorizers, to dissolve substances, and as starting chemicals for making other chemicals. 

Respiratory Effects. Diffuse necrosis of the bronchial epithelium was noted in a woman who died after drinking 500-750 mL of a concentrated cresol mixture (Labram and Gervais 1968). This effect was thought to have occurred prior to death. Edema and hemorrhage were also observed, but may have occurred secondary to death. Adhesions and fluid were found in the lungs of a woman who died after drinking a disinfectant suspected of containing cresols (Dellal 1931). 

A considerable amount of o-cresol is consumed directly as either a solvent or disinfectant. o-Cresol is also used as a chemical intermediate for a wide variety of products. o-Cresol is hydrogenated to... 

Cresols are rapidly absorbed thru the skin causing severe burns (Ref 6). They are used as disinfectants, flotation agents ink, paint varnish removers lube oil additives, organic intermediates, and for the production of synthetic resins (Ref 7)... 

Phenols are extracted commercially from coal tar into aqueous base as the phenolate ions. The major commercial use of phenol is in the manufacture of phenolic resin polymers, usually with formaldehyde. Phenols and cresols are used as antiseptics and disinfectants in areas such as bams where the phenol odor can be tolerated. Phenol was the original antiseptic used on wounds and in surgery, starting with the work of Lord Lister in 1885. 

Advantage is taken of the above principle in the preparation of well known disinfectant lysol. Lysol is a system of cresols and water. These two components do not mix completely at ordinary temperatures, but the addition of soap to the given mixture-soap is soluble in both cresol and water-lowers the C.S.T. to such an extent that the two components readily mix with one another at ordinary temperature to form homogeneous solution. 

Uses Cresol is a mixture of three isomeric forms, namely, ortho-, meta-, and paracresol. Cresol is a colorless, yellowish, brownish yellow, or pinkish liquid with a phenolic odor. It is used as an ore flotation agent and as an intermediate in the manufacture of chemicals, dyes, plastics, and antioxidants. It also is used in the manufacture of dyes, paint removers, plastics, stains, resins, chemical disinfectants, flotations, foundries, wool scours, and insulation enamels. 

Water emulsion of phenolics (cresols) used as disinfectants, germicides, and deodorants... 

Microbial degradation of biocides has been described by Hugo [72] who points out that soil organisms are able to break down substances such as phenols added as fumigants. He also reviewed the utilization by bacteria of aromatic compounds (including the preservatives cresol, phenol, benzoic acid and esters of 4-hydroxybenzoic acid). Several types of preservatives and disinfectants, such as the QACs (e.g. cetrimide, cetylpyridinium chloride, benzalkonium chloride), chlorhexidine and phenylethanol can also be inactivated. Significantly, this only occurs at concentrations well below inhibitory or in-use concentrations [33] and thus cannot be responsible for insusceptibility. A further comment about chlorhexidine is given below. 

Tri-cresol.—The product as obtained from coal tar is a mixture of all three isomers and is known as tri-cresol. The properties of the cresols are in general like those of phenol. They also are valuable antiseptics being largely used as disinfectants. 

Solubilization has been used for many years in the formulation of phenolic antiseptic and disinfectant solutions. In the case of Cresol and Soap Solution (Lysol) and Chloroxylenol Solution B.P., soap micelles are used to solubilize the phenolic substances. The soap (anionic surfactant) is formed by reaction of potassium hydroxide with a suitable oil such as linseed oil (in Cresol and Soap Solution) or castor oil (in Chloroxylenol Solution). The solubilizing potential of surfactant solutions for hydrophobic species has also been exploited in the design of cholelitholytic solvents for gallstone dissolution with some limited success. 

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. 

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. ... 

Phenolic compounds such as cresol, chloro-cresol, chloroxylenol and thymol are frequently solubilised with soap to form clear solutions which are widely used for disinfection. Solution of Chloroxylenol BP, for example, contains 5% w/v chloroxylenol with terpineol in an alcoholic soap solution. 

The mixture occurs as a yellow to brownish-yellow liquid that has a characteristic odor of creosote. Cresol is obtained from coal tar or petroleum by alkaline extraction into aqueous medium, acidifleation, and fractional distillation. The mixture is an inexpensive antiseptic and disinfectant. It possesses a phenol coefficient of 2.. >. Cresol is sparingly soluble in water, although alcohols and other organic solvents will. solubili/e it. The drawback to its use as an antiseptic is its unpleasant txlor. 

The mixture of cresols obtained from coal tar is called cresylic acid, an important technical product used as a disinfectant and in the manufacture of resins and tricresyl phosphate. Cresols are useful as raw materials for various chemical products, disinfectants, and synthetic resins. The isomer o-cresol is a starting material for the herbicides 4,6-dinitro-o-cresol and 2-methyl-4-chlorophenoxyacetic acid. The isomers w-cresol and p-cresol are used in phenol-formaldehyde resins and are converted to tricresyl phosphate (a plasticizer and gasoline additive) and to di-t-butyl cresols (antioxidants called BHT). 

Cresol was a commonly used disinfectant in poultry houses but has been gradually withdrawn and replaced by less toxic disinfectants. Nevertheless, in some regions and countries cresol is still being used. Cresol poisoning in the chicken usually occurs at 3-6 weeks of age. Affected chicks are depressed and have a tendency to huddle. There are respiratory problems such as rales, gasping, and wheezing. With prolonged cresol exposure some chicks will develop edema of the abdomen. 

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