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Earwax

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Earwax
Other namesCerumen
Wet-type human earwax
Pronunciation
SpecialtyOtorhinolaryngology
PrognosisPrevalence

Earwax,also known by the medical termcerumen,is awaxysubstance secreted in theear canalof humans and other mammals. Earwax can be many colors, including brown, orange, red, yellowish, and gray. Earwax protects the skin of the humanear canal,assists in cleaning and lubrication, and provides protection againstbacteria,fungi,particulate matter, and water.[1]

Major components of earwax includecerumen,produced by a type ofmodified sweat gland,andsebum,an oily substance. Both components are made by glands located in theouter[2]ear canal.The chemical composition of earwax includeslong chain fatty acids,bothsaturatedandunsaturated,alcohols,squalene,andcholesterol.Earwax also containsdeadskin cellsand hair.[3]

Excess or compacted cerumen is the buildup of ear wax causing a blockage in the ear canal[2]and it can press against theeardrumor block the outside ear canal orhearing aids,potentially causinghearing loss.

Physiology

Main article:ABCC11
Earwax in ear
Dry-type human earwax
World map of the distribution of the A allele of the single nucleotide polymorphism rs17822931 in theABCC11gene associated with dry-type earwax. The proportion of A alleles (dry-type earwax) in each population is represented by the white area in each circle.

Cerumen is produced in thecartilaginousouter third portion of the ear canal. It is a mixture ofsecretionsfromsebaceous glandsand less-viscous ones from modifiedapocrine sweat glands.[4]The primary components of both wet and dry earwax are shed layers of skin, with, on average, 60% of the earwax consisting ofkeratin,12–20% saturated and unsaturated long-chain fatty acids, alcohols,squaleneand 6–9%cholesterol.[5]

Wet or dry

There are twogenetically-determined types of earwax: thewet type,which isdominant,and thedry type,which isrecessive.This distinction is caused by asingle base changein the "ATP-binding cassette C11 gene".Dry-type individuals arehomozygousforadenine(AA) whereas wet-type requires at least oneguanine(AG or GG).[6]Dry earwax is gray or tan and brittle, and is about 20%lipid.[5]It has a smaller concentration of lipid and pigment granules than wet earwax.[5]Wet earwax is light brown or dark brown and has aviscousand sticky consistency, and is about 50% lipid.[5]Wet-type earwax is associated witharmpit odor,which is increased bysweatproduction.[6][7]

SomeEast Asians(includingYamatoJapanese),Southeast AsiansandNative Americans(includingInuit[8]) are more likely to have the dry type of earwax (gray and flaky), whileAfricans,Europeans,and other East Asians (includingAinu[9]) are more likely to have wet type earwax (honey-brown, dark orange to dark-brown and moist).[10]30–50% ofSouth Asians,Central AsiansandPacific Islandershave the dry type of cerumen.[11]

Cleaning

Cleaning of the ear canal occurs as a result of the "conveyor belt" process ofepithelialmigration, aided byjawmovement.[12]From theumbo,cells formed in the center of thetympanic membranemove to the walls of the ear canal, and then towards the entrance of the ear canal. The cerumen in the ear canal is also carried outwards, taking with it particulate matter that may have gathered in the canal. Jaw movement dislodges debris from the walls of the ear canal to assist in this process.

Removing earwax is in the scope of practice foraudiologistsandotorhinolaryngologists(ear, nose, and throat doctors).

Lubrication

The lubrication provided by cerumen preventsdryingof theskinwithin the ear canal. The highlipidcontent of thesebumproduced by the sebaceous glands causes the cerumen to work likelubrication.In wet-type cerumen, these lipids includecholesterol,squalene,and many long-chainfatty acidsandalcohols.[13][14]

Antimicrobial effects

While studies conducted up until the 1960s found little evidence supporting antibacterial activity for cerumen,[15]more recent studies have found that cerumen has a bactericidal effect on some strains of bacteria. Cerumen has been found to reduce the viability of a wide range of bacteria, includingHaemophilus influenzae,Staphylococcus aureus,and many variants ofEscherichia coli,sometimes by as much as 99%.[16][17]The growth of twofungicommonly present inotomycosiswas also significantly inhibited by human cerumen.[18]These antimicrobial properties are due principally to the presence ofsaturatedfatty acids,lysozymeand, especially, to the slight acidity of cerumen (pHtypically around 6.1 in average individuals[19]). Conversely, other research has found that cerumen can support microbial growth and some cerumen samples were found to have bacterial counts as high as 107/g cerumen. The bacteria were predominantlycommensals.[20]

Excess earwax (impacted cerumen)

Earwax helps protect the ear by trapping dust and other foreign particles that could filter through and damage the eardrum.[5]Normally, earwax moves toward the opening of the ear and falls out or is washed away, but sometimes excessive earwax can gather and become hard to remove. This is referred to as excessive earwax or impacted cerumen.[21]

Excessive earwax may impede the passage ofsoundin the ear canal, causing mild[22]conductive hearing loss,pain in the ear, itchiness, or dizziness. Untreated impacted wax can result in hearing loss,social withdrawal,poor work function, and mildparanoia.People with impacted wax may also present withperforated eardrums;this is usually induced by putting objects in the ear in an attempt to remove the wax.[5]Aphysical examusually checks for visibility of thetympanic membrane,which can be blocked by excessive cerumen.

Impacted cerumen may improve on its own, but treatment by a doctor is generally safe and effective. Hearing usually returns completely after the impacted earwax is removed.

Hearing aids may be associated with increased earwax impaction[23]by blocking earwax from leaving the ear canal.[5]Earwax can also get into a hearing aid's vents and receivers, and degrades the components inside the hearing aid due to its acidity.[24]Earwax is estimated to be the cause of 60–80% ofhearing aidfaults. Excessive earwax can also causetinnitus,a constant ringing in the ears,[25]ear fullness, hearing loss and ear pain.[5]

Impacted earwax is more common in those withDown's syndrome,due to the smaller, curved shape of the ear canal.[26]

Treatment

Movement of the jaw helps the ears' natural cleaning process. TheAmerican Academy of Otolaryngologydiscourages earwax removal, unless the excess earwax issymptomatic.[27]

While a number of methods of earwax removal are effective, their comparative merits have not been determined.[28]A number of softeners are effective; however, if this is not sufficient,[28]the most common method of cerumen removal issyringingwith warm water.[29]Acurettemethod is more likely to be used byaudiologistsandotolaryngologistswhen the ear canal is partially occluded and the material is not adhering to the skin of the ear canal, but due to the high skill level needed to not damage the eardrum, is limited.[5]Cotton swabsare not recommended as they push most of the earwax farther into the ear canal and remove only a small portion of the top layer of wax that happens to adhere to the fibers of the swab.[30]

Softeners

Main article:Cerumenolytics

This process is referred to ascerumenolysis.Topical preparations for the removal of earwax may be better than no treatment, and there may not be much difference between types, including water and olive oil.[28][31]However, there were not enough studies to draw firm conclusions, and the evidence on irrigation and manual removal is equivocal.[28]

Commercially or commonly availablecerumenolyticsinclude:[32]

A cerumenolytic should be used 2–3 times daily for 3–5 days prior to the cerumen extraction.[33]

Microsuction

Microsuction involves the use of a vacuum suction probe to break up and extract impacted cerumen. Microsuction can be preferred over other methods as it avoids the presence of moisture in the ear, is often faster than irrigation, and is performed with direct vision of the earwax being removed.[34]Typically, a camera with lights and guide hole is utilised, with a long metal vacuum probe being inserted into the guide hole - the practitioner is then able to see inside the ear and remove earwax under pressure. Potential adverse effects include dizziness, temporary tinnitus, and reduced hearing due to volume of the pump and the proximity of the vacuum probe to the ear drum - the frequency of these are reduced where the cerumen is softened in the five days preceding microsuction. In general, microsuction is well tolerated and even preferred by many patients.[35]

Ear irrigation

Once the cerumen has been softened, it may be removed from the ear canal by irrigation, but the evidence on this practice is ambiguous.[28]If a patient has a perforated eardrum, syringing can force infections into the middle ear, and residual water can cause an infection in the outer ear.[5]

This may be effectively accomplished with a spray type ear washer, commonly used in the medical setting or at home, with a bulbsyringe.[36]Ear syringing techniques are described in great detail by Wilson & Roeser[33]and Blake et al.[37]who advise pulling the external ear up and back, and aiming the nozzle of the syringe slightly upwards and backwards so that the water flows as a cascade along the roof of the canal. The irrigation solution flows out of the canal along its floor, taking wax and debris with it. The solution used to irrigate the ear canal is usually warm water,[37]normalsaline,[38]sodium bicarbonate solution,[39]or a solution of water andvinegarto help prevent secondary infection.[37]

Affected people generally prefer the irrigation solution to be warmed to body temperature,[38]asdizzinessis a common side effect of ear washing or syringing with fluids that are colder or warmer than body temperature.[29][37]

Mechanical removal using a curette or cotton swabs

Earwax can be removed with anear pickor curette, which physically dislodges the earwax and scoops it out of the ear canal.[40]In the West, use of ear picks is usually only done by health professionals. Curetting earwax using an ear pick was common inancient Europeand is still practised inEast Asia.Since the earwax of most Asians is of the dry type,[10]it is extremely easily removed by light scraping with an ear pick, as it simply falls out in large pieces or dry flakes.

It is generally advised not to usecotton swabs(Q-Tips or cotton buds), as doing so will likely push the wax farther down the ear canal, and if used carelessly,perforatetheeardrum.[30]Abrasion of the ear canal, particularly after water has entered from swimming or bathing, can lead to ear infection. Also, the cotton head may fall off and become lodged in the ear canal. Therefore, cotton swabs should be used only to clean the external ear.

Ear candles

Main article:Ear candling

Ear candlingis a dangerous, ineffective, and counterproductive[27][41]alternative medicinepractice that involves a lighting a hollow candle and placing the unlit end in the ear canal. Advocates say that the dark residue appearing on the candle after the procedure consists of extracted earwax, but studies show that the same dark residue is left regardless of whether the candle is inserted into an ear, as the residue is derived from the candle itself and not the ear.[42]TheAmerican Academy of Otolaryngologystates that ear candles are not a safe option for removing ear wax, and that no controlled studies or scientific evidence support their use for ear wax removal.[43]Survey responses from medical specialists (otolaryngologists) in the United Kingdom reported ear injuries including burns, ear canal occlusions and ear drum perforations and secondary ear canal infections with temporary hearing loss from ear candling.[41]TheFood and Drug Administrationhas taken several regulatory actions against the sale and distribution of ear candles since 1996, including seizing ear candle products and ordering injunctions, and ear candles are now marked as "providing no health benefit".[43]

Ear vacuuming

Home "ear vacs" were ineffective at removing ear-wax when compared to a Jobson-Horne probe.[44]

Potential complications

A postal survey of British general practitioners[29]found that only 19% always performed cerumen removal themselves. It is problematic as the removal of cerumen is not without risk, and physicians and nurses often have inadequate training for removal. Irrigation can be performed at home with proper equipment as long as the person is careful not to irrigate too hard. All other methods should be carried out only by individuals who have been sufficiently trained in the procedure.

The author Bull advised physicians: "After removal of wax, inspect thoroughly to make sure none remains. This advice might seem superfluous, but is frequently ignored."[39]This was confirmed by Sharp et al.,[29]who, in a survey of 320 general practitioners, found that only 68% of doctors inspected the ear canal after syringing to check that the wax was removed. As a result, failure to remove the wax from the canal made up approximately 30% of the complications associated with the procedure. Other complications includedotitis externa(swimmer's ear), which involves inflammation or bacterial infection of the external acoustic meatus, as well aspain,vertigo,tinnitus,and perforation of the ear drum. Based on this study, a rate of major complications in 1/1000 ears syringed was suggested.[29]

Claims arising from ear syringing mishaps account for about 25% of the total claims received by New Zealand'sAccident Compensation CorporationENT Medical Misadventure Committee.[37]While high, this is not surprising, as ear syringing is an extremely common procedure. Grossan suggested that approximately 150,000 ears are irrigated each week in the United States, and about 40,000 per week in the United Kingdom.[45]Extrapolating from data obtained in Edinburgh, Sharp et al.[29]place this figure much higher, estimating that approximately 7000 ears are syringed per 100,000 population per annum. In the New Zealand claims mentioned above, perforation of the tympanic membrane was by far the most common injury resulting in significant disability.

Prevalence

The prevalence of impacted earwax is different across the world.

In the United Kingdom 2 to 6% of the population have cerumen that is impacted. In America 3.6% of emergency visits caused by ear issues were due to impacted cerumen. In Brazil 8.4–13.7% of the population have impacted cerumen.[46]

History

An ear-cleaner, attending to a man's ear. Gouache painting, Delhi, 1825.

The treatment of excess ear wax was described byAulus Cornelius CelsusinDe Medicinain the 1st century:[47]

When a man is becoming dull of hearing, which happens most often after prolonged headaches, in the first place, the ear itself should be inspected: for there will be found either a crust such as comes upon the surface ofulcerations,or concretions of wax. If a crust, hot oil is poured in, orverdigrismixed withhoneyorleekjuice or a littlesodainhoney wine.And when the crust has been separated from the ulceration, the ear is irrigated with tepid water, to make it easier for the crusts now disengaged to be withdrawn by theear scoop.If it is wax, and if it is soft, it can be extracted in the same way by the ear scoop; but if hard,vinegarcontaining a littlesoda[48]is introduced; and when the wax has softened, the ear is washed out and cleared as above.... Further, the ear should be syringed withcastoreummixed with vinegar andlaureloil and the juice of youngradishrind, or withcucumberjuice, mixed with crushedroseleaves. The dropping in of the juice of unripegrapesmixed withrose oilis also fairly efficacious against deafness.

Uses

  • In medieval Europe, earwax and other substances such asurinewere used to preparepigmentsused byscribesto illustrateilluminated manuscripts.[49]
  • Pliny the Elder,in hisNatural History,wrote that earwax—when applied topically—cured bites from humans, scorpions, and serpents; it was said to work best when taken from the ears of the wounded person itself.[50]
  • Early Americanlip balmsmay have been based on earwax.[51]The 1832 edition of theAmerican Frugal Housewifesaid that "nothing was better than earwax to prevent the painful effects resulting from a wound by a nail [or] skewer"; and also recommended earwax as aremedy for cracked lips.[52]
  • Before waxed thread was commonly available, a seamstress would use her own earwax to stop the cut ends of threads from fraying.[53]
  • Earwax retains concentrations ofcortisolover time. As cortisol levels change throughout the day and increase in response to stress, long-term measurements are difficult yet necessary. A 2020 study suggests swabbing earwax as a method of measuring long-term cortisol levels that is noninvasive and does not confound itself.[54]

Notes

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  6. ^abYoshiura K, Kinoshita A, Ishida T, Ninokata A, Ishikawa T, Kaname T, et al. (March 2006)."A SNP in the ABCC11 gene is the determinant of human earwax type".Nature Genetics.38(3): 324–330.doi:10.1038/ng1733.ISSN1546-1718.PMID16444273.S2CID3201966.
  7. ^Nakano, Motoi, Nobutomo Miwa, Akiyoshi Hirano, Koh-ichiro Yoshiura, and Norio Niikawa. "A strong association of axillary osmidrosis with the wet earwax type determined by genotyping of the ABCC11 gene." BMC genetics 10, no. 1 (2009): 42.
  8. ^Bass EJ, Jackson JF (September 1977). "Cerumen types in Eskimos".American Journal of Physical Anthropology.47(2): 209–10.doi:10.1002/ajpa.1330470203.PMID910884.
  9. ^"Miscellaneous musings on the Ainu, I".Ahnenkult.com. Archived fromthe originalon 11 June 2016.Retrieved28 April2014.
  10. ^abOverfield T (1985).Biologic variation in health and illness: race, age, and sex differences.Menlo Park, Calif: Addison-Wesley, Nursing Division. p.46.ISBN978-0-201-12810-9.... most common type in Whites and Blacks is dark brown and moist. Dry wax, most common in Orientals and Native Americans, is gray and dry. It is flaky and may form a thin mass that lies in the ear canal.
  11. ^"The science of stinky sweat and earwax".Australian Broadcasting Corporation.14 April 2015.
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  23. ^Chou, R.; Dana, T.; Bougatsos, C.; Fleming, C.; Beil, T. (March 2011)."Screening for Hearing Loss in Adults Ages 50 Years and Older: A Review of the Evidence for the U.S. Preventive Services Task Force".Evidence Syntheses, No. 83.U.S. Agency for Healthcare Research and Quality (AHRQ).PMID21542547.Retrieved5 July2013.
  24. ^Oliveira RJ (December 1997). "The active earcanal".Journal of the American Academy of Audiology.8(6): 401–10.PMID9433686.
  25. ^Aleccia J (29 August 2018)."The Dangers of Excessive Earwax".Scientific American.
  26. ^"Cerumen Impaction | Adult Down Syndrome Center".adscresources.advocatehealth.com.Retrieved10 May2023.
  27. ^abSchwartz SR, Magit AE, Rosenfeld RM, Ballachanda BB, Hackell JM, Krouse HJ, et al. (January 2017)."Clinical Practice Guideline (Update): Earwax (Cerumen Impaction) Executive Summary".Otolaryngology–Head and Neck Surgery.156(1): 14–29.doi:10.1177/0194599816678832.PMID28045632.
  28. ^abcdeClegg AJ, Loveman E, Gospodarevskaya E, Harris P, Bird A, Bryant J, et al. (June 2010)."The safety and effectiveness of different methods of earwax removal: a systematic review and economic evaluation".Health Technology Assessment.14(28): 1–192.doi:10.3310/hta14280.hdl:10536/DRO/DU:30064293.PMID20546687.
  29. ^abcdefSharp JF, Wilson JA, Ross L, Barr-Hamilton RM (December 1990)."Ear wax removal: a survey of current practice".BMJ.301(6763): 1251–3.doi:10.1136/bmj.301.6763.1251.PMC1664378.PMID2271824.
  30. ^ab"Ear wax".Tchain.com. Archived fromthe originalon 23 September 2018.Retrieved2 May2010.
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  32. ^Fraser JG (October 1970). "The efficacy of wax solvents: in vitro studies and a clinical trial".The Journal of Laryngology and Otology.84(10): 1055–64.doi:10.1017/s0022215100072856.PMID5476901.
  33. ^abWilson PL, Roeser RJ (December 1997). "Cerumen management: professional issues and techniques".Journal of the American Academy of Audiology.8(6): 421–30.PMID9433688.
  34. ^Radford JC (2020)."Treatment of impacted ear wax: a case for increased community-based microsuction".BJGP Open.4(2): bjgpopen20X101064.doi:10.3399/bjgpopen20X101064.PMC7330231.PMID32238391.
  35. ^Cronin T, Zhao F (2020). "Temporary threshold shift following ear canal microsuction".International Journal of Audiology.59(9): 713–718.doi:10.1080/14992027.2020.1746977.PMID32282254.S2CID215757310.
  36. ^Coppin R, Wicke D, Little P (2011)."Randomized trial of bulb syringes for earwax: impact on health service utilization".Annals of Family Medicine.9(2): 110–4.doi:10.1370/afm.1229.PMC3056857.PMID21403136.
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  38. ^abErnst AA, Takakuwa KM, Letner C, Weiss SJ (September 1999). "Warmed versus room temperature saline solution for ear irrigation: a randomized clinical trial".Annals of Emergency Medicine.34(3): 347–50.doi:10.1016/S0196-0644(99)70129-0.PMID10459091.
  39. ^abBull, P. D. (2002).Lecture notes on diseases of the ear, nose, and throat(6th ed.). Oxford: Blackwell Science. pp. 26–27.ISBN978-0-632-06506-6.
  40. ^Evidences Based Cerumen Removal ProtocolArchived4 March 2016 at theWayback Machine
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  47. ^Celsus AC,W.G. Spencer translation."Book VI".De Medicina.
  48. ^"acetum et cum eo nitri paulum".Nitriis rendered as "soda" here, i.e.soda ash,though the word can refer to a variety of alkaline substances or tosodium nitrate.(http://www.archives.nd.edu/cgi-bin/words.exe?nitrihttp://www.history-science-technology.com/Notes/Notes%208.htm) Note that acidification of sodium carbonate yieldssodium bicarbonate.
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  52. ^Child LM (1841).The American Frugal Housewife: Dedicated to Those who are Not Ashamed of Economy.p. 116.
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  54. ^Herane-Vives, Andres; Ortega, Lorena; Sandoval, Rodrigo; Young, Allan H.; Cleare, Anthony; Espinoza, Susana; Hayes, Alexander; Benöhr, Jan (November 2020)."Measuring Earwax Cortisol Concentration using a non-stressful sampling method".Heliyon.6(11): e05124.Bibcode:2020Heliy...605124H.doi:10.1016/j.heliyon.2020.e05124.PMC7644886.PMID33195832.

Further reading

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