This step is basically the reverse of step two. Since most staining agents are water soluble, the paraffin must be removed first. To do this, the sectioned samples are passed through xylene in order to remove the paraffin. When stained, the samples are again dehydrated and placed in xylene. The sections are then mounted on microscope slides in a medium dissolved in xylene.
A cover slip is put on top of each sample and the xylene is allowed to dry. Finally, the mounting medium hardens and binds the coverslip on the microscope slide. As a paint thinner, this chemical has some advantages over other paint thinning agents like toluene.
This allows you to apply paint more evenly on a surface. Xylene is also the preferred thinner for those who use spray paints because it facilitates a better flow.
Even if you use a paint brush or a roller, you can prevent clots or chunks by using xylene as a paint thinner. The blog on chemicals. The blog, its authors and affiliates accept no responsibility for any accident, injury or damage caused in part or directly from following the information provided on this website. We do not recommend using any chemical without first consulting the Material Safety Data Sheet which can be obtained from the manufacturer and following the safety advice and precautions on the product label.
Synthetic sea water is also known as artificial sea water ASW and substitute ocean water, and is mainly used Determining the rate of chemical reactions can be done using rate equations, no matter what type of chemical reaction Isopropanol, which is also known as isopropyl alcohol IPA and propanol, has a range of applications across many industries Sodium thiosulphate Na2S2O3 is considered one of the most important medicines in the health system because of its ability In chemistry, pure chemicals refer to substances that only contain one type of fundamental unit, like an atom or Propylene Glycol C3H8O2 is a synthetic organic compound that absorbs water.
Chemically recognised as a diol because of its Address for correspondence: Dr. E-mail: moc. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article has been cited by other articles in PMC. Abstract Xylene is an aromatic hydrocarbon known for its wide usage in tissue processing, staining and cover slipping in the histology laboratory.
Keywords: Toxicity of xylene, xylene substitutes, xylene. Table 1 Effect of xylene on the nervous system. Open in a separate window. LUNGS Exposure to xylene at levels of ppm or greater can irritate the lungs, causing chest pain and shortness of breath. The chemical components are one of the following:[ 15 ] Limonene reagents Aliphatic hydrocarbon mixtures Aromatic hydrocarbon mixtures Mineral oil mixtures Limonene reagents Mainly composed of d-limonene, which is a hydrocarbon.
Table 2 Advantages and disadvantages of limonene reagents. Advantages Disadvantages Biodegradable, noncorrosive, nonflammable combustible Expensive Contains no benzene and no toluene Claims to be less toxic but the hazards are not well documented Low toxicity levels Offensive odor Minimal tissue shrinkage Very oily Soluble in alcohol and mounting media Incompatible with some of the mounting media Reasonably fast drying and leaves no residue Cannot be distilled Reduced fire risk Samples take more time to dry thoroughly Has a high vapor pressure, and thus does not evaporate fast.
Degreasing effect on skin Hence, cover slipping multiple slides is easy. Table 3 Advantages and disadvantages of aliphatic hydrocarbon mixtures. Advantages Disadvantages Most of them are odorless Classified as hazardous waste due to flammability Can be recovered by distillation Not easily biodegradable Less expensive than limonene reagents More expensive than xylene Nongreasy some of them Less irritating to the skin than xylene and d-limonene-based clearants Less tolerant of contamination than xylene Less toxic because they are catalytically hydrogenated to destroy the double bonds.
Aromatic hydrocarbon mixtures Some high-boiling aromatic hydrocarbon mixtures having lower volatility than xylenes have been manufactured. Mineral oil mixtures Mineral paraffin oil mixtures look promising in eliminating xylene from most of the procedures.
Local exhaust ventilation The workplace can be modified to reduce the inhalational hazards by installing local exhaust ventilation with a proper hood. Figure 1. Get medical attention as soon as possible Skin exposure: The contaminated skin should be washed with soap and water for at least 15 min. If irritation persists, get medical attention Inhalation: If xylene vapors are inhaled, move the victim at once to fresh air and get medical care as soon as possible. Keep the victim warm and quiet until medical help arrives Ingestion: If xylene or a solution containing xylene is ingested, give the victim several glasses of water to drink.
Toxicological profile for xylene, U. S Department of Health and Human Services, public health service, Agency for toxic substance and disease registry. Sedivec V, Flek J. Exposure test for xylenes. Int Arch Occup Environ Health. Urinary excretion of hippuric acid and m- or p-methylhippuric acid in the urine of persons exposed to vapours of toluene and m- or p- xylene as a test of exposure.
Br J Ind Med. Savoleinen H, Pfaffli P. Dose-dependent neurochemical changes during short-term inhalation exposure to m-xylene. Arch Toxicol. Significant changes in the amounts of neurotransmitter and related substances in rat brain induced by subacute exposure to low levels of toluene and xylene. Ind Health.
Production of discrete changes in dopamine and noradrenaline levels and turnover in various parts of the rat brain following exposure to ortho-, meta- and para-xylenes, and ethylbenzene. Toxicol Appl Pharmacol. Symptoms and signs in workers exposed predominantly to xylene. Hipolito RN.
Xylene poisoning in laboratory workers: Case reports and discussion. Lab Med. Riihimaki V. Percutaneous absorption of m-xylene from a mixture of m-xylene and isobutyl alcohol in man. Scand J Work Environ Health. Percutaneous absorption of m-xylene in man.
Testicular atrophy and loss of nerve growth factor-immunoreactive germ cell line in rats exposed to n-hexane and a protective effect of simultaneous exposure to toluene or xylene. Arch Toxicll. Spontaneous abortions and congenital malformations among the wives of men occupationally exposed to organic solvents. In: Pollution prevention and waste minimization in laboratories.
Florida: CRC pressLewis publishers; Xylene substitutes; p. Sustainable hospitals project. Pilot study of alternatives to the use of xylene in a hospital histology laboratory. Fundamentals of clearing. Wynnchuk M. Evaluation of xylene substitutes for paraffin tissue processing.
J Histotechnol. Xylene substitutes in frozen sections. Dermatol Surg. Histology Without xylene. Ann Diagn Pathol. Beusa RJ. Mineral oil: The best xylene substitute for tissue processing yet?
Chemical hazards. The chief use of p-xylenesulfonic acid is as a reagent to determine serum cholesterol levels. While xylene serves many valuable uses across multiple industries, it comes with its own risks to those who work closely with this chemical compound.
Children are more greatly affected by xylene than adults, so extraordinary care must be taken to prevent their exposure. The primary risks of xylene exposure include effects from inhalation or contact with the skin or eyes. Xylene is not classified as a carcinogen.
Xylene is considered a central nervous system depressant, meaning it slows down the central nervous system. Breathing in xylene can cause dizziness, nausea, fainting, headache and even vomiting.
Visual impairment and difficulty may also result from xylene exposure. Other drastic symptoms might include tremors, heart arrhythmias and pulmonary edema. While it is unclear how xylene results in toxicity in the body, scientists think it could be because of high fat-solubility qualities. In this way it could be soluble with lipids in the membranes of neurons, and could affect neuronal proteins as a result.
More research is needed to determine the method of toxicity. Xylene also poses risks to skin and eyes and is considered a skin irritant. The skin quickly absorbs it. Because xylene is so efficient at removing fats, any contact with the skin will have the same effect.
This can lead to drying and cracking of the skin and dermatitis. If xylene comes in contact with the eyes, it can damage the cornea. It is crucial to wear safety goggles when working with xylene. Any ingestion by mouth should be taken very seriously as well by quickly obtaining medical aid.
Longer exposure to xylene yields greater risk. Even smelling it can affect major organs. The best protective measures you can take around xylene are to work in a properly ventilated environment, such as a hood that vents quickly outside the area; a respirator mask as needed; and to wear proper protective eye goggles, gloves, protective clothes and aprons.
Exposed individuals should be removed from the contamination, and medical assistance should be sought. Because xylene is heavier than air, it can reside in pockets near the ground. Therefore it is wise to remove persons from low-lying areas near the xylene contamination. Also, any xylene vapor trapped in clothing can affect helpers. Those who work regularly with xylene should be given routine medical examinations, and have body fluids monitored.
Always review material safety data sheets in areas that use xylene and other powerful chemicals. She spent nine years working in laboratory and clinical research. A lifelong writer, Dianne is also a content manager and science fiction and fantasy novelist. Dianne features science as well as writing topics on her website, jdiannedotson.
Additional uses of xylene include its addition to pesticides and disinfectants. Alternative Solvents to Benzene. What Is Sodium Lauryl Sulfate? Ingredients in Carburetor Cleaners.
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