Salicylic acid is found of course in the bark of the willow tree. It has been used for centuries to alleviate a assortment of complaints. It has besides been developed in a assortment of merchandises in the countries of tegument attention, cosmetics and tummy alleviation. Salicylic acid is a wonder drug. But what are its physical and chemical belongingss? What chemical reactions are used in fabrication and utilizing salicylic acid? Does it stand for any safety hazards to society and the environment?
Salicylic acid was discovered by the Grecian doctor Hippocrates in the fifth century BC.[ 1 ]He found that the acrimonious pulverization extracted from willow bark could alleviate achings and strivings and cut down febrilities.[ 2 ]The redress is besides mentioned in Hagiographas from ancient Sumer, Lebanon, and Assyria. Cherokee and other Native Americans used the bark for febrility and other medicative intents for centuries. The medicative portion of the works is the interior bark. It is used as a hurting stand-in for a assortment of complaints. The clergyman Edward Stone from Oxfordshire, England found in 1763 that willow bark was utile in cut downing febrility.
The active infusion of the bark is called Salicin, after the Latin name of the white willow ( salix alba ) .[ 3 ]The infusion was isolated and named by Johann Buchner in Germany in 1826. A larger sum of the substance was isolated in 1828 by the Gallic druggists, Hanri Laroux.[ 4 ]The Italian chemist, Raffaele Piria was able to change over the infusion into a chemical which become salicylic acid when it oxidises.[ 5 ]
In 1839, Salicylic acid was besides extracted by German research workers from the herb meadowsweet ( Filpendula ulmaria ) . This infusion was effectual but it caused digestive jobs such as stomachic annoyance, hemorrhage, diarrhea and decease if consumed in high doses.[ 6 ]
Salicylic Acid is still used today to ease achings and strivings and to cut down febrilities. It was used as an anti-inflammatory drug even in ancient times.
Salicylic is a chief ingredient in many skin attention merchandises handling acne, psoriasis, callosities, maizes, keratosis pilaris and warts. Salicylic acid works as a keratolytic and comedolytic agent. It causes the cells of the cuticle to cast more easy, opening clogged pores and neutralizing bacteriums within. It can besides forestall pores from choke offing up once more by compressing pore diameter, and leting for new cell growing. Due to its consequence on tegument cells, salicylic acid is used in some shampoos to handle dandruff.
Salicylic Acid has the visual aspect of a colorless crystalline pulverization. It is odorless or may hold a little phenolic smell.[ 7 ]It has a sweetish gustatory sensation.[ 8 ]It has a runing point of 159A° C and a sublimation point of 76A° C. Its comparative denseness is 1.4 compared to H2O which has a comparative denseness of 1. Its solubility in H2O is 0.2 g/100 milliliter at 20A°C.[ 9 ]It is soluble in intoxicant, ether, boiling H2O.[ 10 ]It has a pH of 2.4.
It is a polar molecule which explains its low solubility in H2O. It was a molar mass of 138.1 g/mol. Its chemical expression is C6H4 ( OH ) COOH and an empirical expression of C7H6O3. It will auto-ignite at every bit low as 540A°C. It is a comparatively stable compound but oxidising agents, strong bases, I, and F may do strong reactions.[ 11 ]It is besides sensitive to visible radiation. It can be harmful if inhaled, ingested or absorbed through tegument. It is an thorn.
Manufacturing Salicylic Acid
Salicylic acid signifiers in nature in Salix, the bark of the willow tree. While the pulverization extracted from the bark could be sold today, it seldom is because it pureness is non changeless.
To do salicylic acid in a lab, chemists can set sodium phenoxide and C dioxide under high pressurization.[ 12 ]Once this mixture is acidified utilizing sulfuric acid, salicylic acid will ensue. This procedure is called a Kolbe-Schmitt reaction. This method consequences in much purer and more consistent merchandise that can be used of pharmaceutical or commercial readyings.
Using Salicylic Acid
Salicylic acid plants on tegument by softening ceratin, one of the proteins in the tegument construction. With the ceratin softened, the tegument sheds easier. When being used for warts the tegument is softened and the wart can fall off. When being used for acne, the increased sloughing prevents choke offing in the pore.
Medicines like salicylic acid are called keratolytics because they can soften and ease the exfoliation of cuticular cells. Salicylic acid is besides a comedolytic medicine because it can interrupt up blackheads and open clogged pores.
Salicylic Acid, when taken orally, is besides an analgetic and an anti-inflammatory. It can alleviate hurting and cut down redness. Salicylic acid blocks the production of certain endocrines called prostaglandins that are released from damaged cells. Prostaglandins, if non blocked, trigger the release of other endocrines that cause the nervousnesss to be sensitive to trouble. By barricading prostaglandins, the hurting and redness are significantly reduced.
There are many economic benefits to fabricating salicylic acid. Since it relives achings, reduces febrilities and is anti-inflammatory, it can assist cut down the clip people miss at school and at work. For employers, pupils and the full economic system this is a benefit. With people being in less hurting and non enduring from febrilities and swelling, visits to the infirmary and physician ‘s office will be reduced. This will ease the burden on the medical system. One can conceive of how high the gross revenues of acetylsalicylic acid are and this would non be possible without salicylic acid. There is evidently besides a enormous economic benefit to the industry of many skin attention merchandises that use salicylic acid. Acne, wart, psoriasis, callosities, maizes and keratosis are really common complaints therefore gross revenues of the tegument attention merchandises would be really high. There is money to be made in the country of cosmetics with merchandises to exfoliate cuticular cells and unfastened clogged pores. In add-on to this, gross revenues of dandruff shampoo and tummy AIDSs ( both of which contain salicylic acid or its derived functions ) , must be really high.
The history of salicylic acid represents continual technological development. What started as a simple infusion from the willow tree became many utile merchandises over the centuries. Throughout history chemists have worked difficult to develop extra utilizations for salicylic acid. Chemists discovered its anti-inflammatory belongingss. These belongingss have been researched and have helped the development of modern anti-inflammatory medicines.
Salicylic acid can be harmful if inhaled, ingested, or absorbed through tegument. If inhaled, it can do effects such as coughing, sneezing and shortness of breath. If ingested in a big sum salicylism may ensue which is characterised by abdominal hurting, emesis, mental perturbations and increased respiration.[ 13 ]It is a mild thorn and may do a skin roseola in persons that are sensitive to it. Salicylic acid is an utmost oculus thorn which was shown in carnal testing.[ 14 ]Chronic exposure to salicylic acid can do cardinal nervous perturbations every bit serious as paroxysms. It may do injury to an unborn kid although the effects of salicylic acid during gestation have non been to the full investigated. The salicylic acid used locally is normally really diluted at merely 2 % or used in a really little sum. Plus the sum absorbed through the tegument is really low. Therefore the hazard to an single applying it locally is minimum.
Salicylic acid should be stored in a tightly closed container that is stored in a cool, dry and ventilated topographic point. It should be protected from physical harm and maintain off from any beginning of heat, ignition or oxidising stuffs. Care should be takes to avoid dust formation as it can light. Empting the contents of a salicylic acid container should be done with attention as empting it into an ambiance where flammable bluess are present can do a brassy fire. Salicylic acid should ever be stored in the dark.
When salicylic acid is released into dirt it will rapidly biodegrade. The same will happen when it is released into H2O. Because it rapidly biodegrade, there is non a major environmental consequence of salicylic acid. However, it should be still disposed of decently. The low concentrations that are found in many skin attention merchandises can be disposed of in the refuse. With Large concentrations or big sums of salicylic acid, they should be disposed of carefully. They should be brought to a accredited waste disposal contractor that observes all local and national ordinances.[ 15 ]
Other Interesting Facts about Salicylic Acid
Salicylic acid has been used as a nutrient preservative. It works as one because of its antiseptic belongingss. It has to be used in really little doses because of its toxicity at high doses. It is no longer used as a nutrient preservative any longer because of concerns with utilizing any antiseptics in human nutrient.[ 16 ]Salicylic acid can do ear harm when taken orally because it inhibits prestin. This lone happens in people with a Zn lack. However if Zn is injected, the hearing loss can be reversed.[ 17 ]Salicylic acid, was one time the universe ‘s bestselling drug in 1898.[ 18 ]Salicylic acid is besides a works endocrine that causes an addition in growing, blossoming and heat production.[ 19 ]
It is clear that salicylic acid is a really valuable substance. It has many utilizations and applications in medical specialty and cosmetics. It was been available to us for centuries. Salicylic acid is an odourless, colorless crystalline pulverization. It can respond with certain chemicals. It is manufactured in a Kolbe-Schmitt reaction and it is used to soften the tegument doing it good for handling many complaints. Salicylic acid must be stored safely and disposed of decently.