Editing Xylene (section)

==Health and safety==
Xylene is flammable but of modest acute toxicity, with {{LD50}} ranges from 200 to 5000&nbsp;mg/kg for animals. Oral {{LD50}} for rats is 4300&nbsp;mg/kg. The principal mechanism of detoxification is oxidation to [[toluic acid|methylbenzoic acid]] and hydroxylation to hydroxylene.<ref name="Ullmann" />

The main effect of inhaling xylene vapor is [[CNS depression|depression of the central nervous system]] (CNS), with symptoms such as headache, dizziness, nausea and vomiting. At an exposure of 100&nbsp;ppm, one may experience nausea or a headache. At an exposure between 200 and 500&nbsp;ppm, symptoms can include feeling "high", dizziness, weakness, irritability, vomiting, and slowed reaction time.<ref name=":0">{{Cite journal |title = Xylene: An overview of its health hazards and preventive measures |journal = Journal of Oral and Maxillofacial Pathology |date = 2010-01-01 |issn = 0973-029X |pmc = 2996004 |pmid = 21180450 |pages = 1–5 |volume = 14 |issue = 1 |doi = 10.4103/0973-029X.64299 |first1 = Reena |last1 = Kandyala |first2 = Sumanth Phani C. |last2 = Raghavendra |first3 = Saraswathi T. |last3 = Rajasekharan |doi-access = free }}</ref><ref>{{Cite web |url=http://oehha.ca.gov/air/acute_rels/pdf/XylenesA.pdf |title=ACUTE TOXICITY SUMMARY: XYLENES |url-status=dead |archive-url=https://web.archive.org/web/20151022131350/http://www.oehha.ca.gov/air/acute_rels/pdf/xylenesA.pdf |archive-date=October 22, 2015 }}</ref>

The side effects of exposure to low concentrations of xylene ({{nowrap|< 200 ppm}}) are reversible and do not cause permanent damage. Long-term exposure may lead to headaches, irritability, depression, insomnia, agitation, extreme tiredness, tremors, hearing loss, impaired concentration and short-term memory loss.<ref>{{Cite web | url=http://www.inchem.org/documents/ehc/ehc/ehc190.htm | title=Xylenes (EHC 190, 1997)}}</ref>{{clarify |reason=short-term memory loss? |date=June 2016}} A condition called [[chronic solvent-induced encephalopathy]], commonly known as "organic-solvent syndrome" has been associated with xylene exposure. There is very little information available that isolates xylene from other solvent exposures in the examination of these effects.<ref name=":0" />

Hearing disorders have been also linked to xylene exposure, both from studies with experimental animals,<ref>{{Cite journal |last1=Gagnaire |first1=F. |last2=Marignac |first2=B. |last3=Langlais |first3=C. |last4=Bonnet |first4=P. |date=July 2001 |title=Ototoxicity in rats exposed to ortho-, meta- and para-xylene vapours for 13 weeks |journal=Pharmacology & Toxicology |volume=89 |issue=1 |pages=6–14 |doi=10.1034/j.1600-0773.2001.d01-129.x |doi-broken-date=15 February 2025 |issn=0901-9928 |pmid=11484912}}</ref><ref>{{Cite journal |last1=Gagnaire |first1=F. |last2=Marignac |first2=B. |last3=Blachère |first3=V. |last4=Grossmann |first4=S. |last5=Langlais |first5=C. |date=2007-03-07 |title=The role of toxicokinetics in xylene-induced ototoxicity in the rat and guinea pig |journal=Toxicology |volume=231 |issue=2–3 |pages=147–158 |doi=10.1016/j.tox.2006.11.075 |issn=0300-483X |pmid=17210216|bibcode=2007Toxgy.231..147G }}</ref> as well as clinical studies.<ref>{{Cite journal |last1=Fuente |first1=Adrian |last2=McPherson |first2=Bradley |last3=Cardemil |first3=Felipe |date=September 2013 |title=Xylene-induced auditory dysfunction in humans |journal=Ear and Hearing |volume=34 |issue=5 |pages=651–660 |doi=10.1097/AUD.0b013e31828d27d7 |issn=1538-4667 |pmid=23598724|s2cid=45206975 |hdl=10533/134303 |hdl-access=free }}</ref><ref>{{Cite journal |last1=Draper |first1=T. H. J. |last2=Bamiou |first2=D.-E. |date=April 2009 |title=Auditory neuropathy in a patient exposed to xylene: case report |journal=The Journal of Laryngology & Otology |volume=123 |issue=4 |pages=462–465 |doi=10.1017/S0022215108002399 |pmid=18439334 |issn=1748-5460|url=http://discovery.ucl.ac.uk/70543/1/S0022215108002399.pdf |archive-url=https://web.archive.org/web/20170809163223/http://discovery.ucl.ac.uk/70543/1/S0022215108002399.pdf |archive-date=2017-08-09 |url-status=live }}</ref><ref>{{Cite journal |last1=Fuente |first1=Adrian |last2=McPherson |first2=Bradley |last3=Hood |first3=Linda J. |date=November 2012 |title=Hearing loss associated with xylene exposure in a laboratory worker |journal=Journal of the American Academy of Audiology |volume=23 |issue=10 |pages=824–830 |doi=10.3766/jaaa.23.10.7 |issn=1050-0545 |pmid=23169198|hdl=10533/137495 |hdl-access=free }}</ref>

Xylene is also a skin irritant and strips the skin of its oils, making it more permeable to other chemicals. The use of impervious gloves and masks, along with respirators where appropriate, is recommended to avoid occupational health issues from xylene exposure.<ref name=":0" />

Xylenes are metabolized to [[methylhippuric acid]]s.<ref name=NIOSH>{{cite web | url = https://www.cdc.gov/niosh/docs/2003-154/pdfs/8301.pdf | work = NIOSH Manual of Analytical Methods (NMAM) | edition = Fourth | title = HIPPURIC and METHYL HIPPURIC ACIDS in urine }}<!-- also found at https://en.wikisource.org/wiki/Hippuric_and_Methyl_Hippuric_Acids_in_Urine_(8301) --></ref><ref name=Inoue>{{Cite journal |pmid = 8482596 |year = 1993 |last1 = Inoue |first1 = O. |title = Excretion of methylhippuric acids in urine of workers exposed to a xylene mixture: Comparison among three xylene isomers and toluene |journal = International Archives of Occupational and Environmental Health |volume = 64 |issue = 7 |pages = 533–539 |last2 = Seiji |first2 = K. |last3 = Kawai |first3 = T. |last4 = Watanabe |first4 = T. |last5 = Jin |first5 = C. |last6 = Cai |first6 = S. X. |last7 = Chen |first7 = Z. |last8 = Qu |first8 = Q. S. |last9 = Zhang |first9 = T. |last10 = Ikeda |first10 = M. |doi=10.1007/bf00381104|bibcode = 1993IAOEH..64..533I |s2cid = 21534640 }}</ref> The presence of methylhippuric acid can be used as a [[biomarker]] to determine exposure to xylene.<ref name=Inoue/><ref>{{Cite journal | author = Kira S. | title = Measurement by gas chromatography of urinary hippuric acid and methylhippuric acid as indices of toluene and xylene exposure | journal = Occupational and Environmental Medicine | date = 1977 | volume = 34 | issue = 305–309 | pages = 305–309 | doi = 10.1136/oem.34.4.305 | pmid = 588486 | pmc = 1008281 }}</ref>