1,4-Dichlorobenzene

December 2019 changed changed 477206149 1,4-Dichlorobenzene 1,4-dichlorobenzene.svg 70px Structural formula of 1,4-Dichlorobenzene skin-invert P-Dichlorobenzene-3D-balls.png Ball-and-stick model of 1,4-dichlorobenzene bg-transparent 1,4 dichlorobenzene crystallised.jpg 1,4-dichlorobenzene crystallised on paper from DCM solution 1,4-Dichlorobenzene 1,4-DCBpara-Dichlorobenzenep-Dichlorobenzenep-DCBPDCBParamothPara crystalsParacideDichlorocide p-DCB1,4-DCBPDCB ClC1=CC=C(Cl)C=C1 changed chemspider 1S/C6H4Cl2/c7-5-1-2-6(8)4-3-5/h1-4H changed chemspider OCJBOOLMMGQPQU-UHFFFAOYSA-N changed chemspider 13866817 4685 203-400-5 3077 correct EBI 28618 correct EBI 190982 correct FDA D149TYB5MK correct CAS 106-46-7 CZ4550000 correct kegg C07092 1680023 49722 6 4 2 1.25 g/cm3, solid 10.5 mg/100 mL (20 °C) 53.5 174 Colorless/white crystals sweet, mothball-like 1.3 mmHg (20 °C) −82.93·10−6 cm3/mol Suspected carcinogen 2 2 0 07 08 09 02 WARNING 302 315 317 319 332 335 351 410 201 202 261 264 270 271 272 273 280 281 301+312 302+352 304+312 304+340 305+351+338 308+313 312 321 330 332+313 333+313 337+313 362 363 391 403+233 405 501 66 TWA 75 ppm (450 mg/m3)0190 2.5%-? Ca [150 ppm] Ca 500 mg/kg (rat, oral)2950 mg/kg (mouse, oral)2512 mg/kg (rat, oral)2830 mg/kg (rabbit, oral) https://www.cdc.gov/niosh/idlh/106467.html p-Dichlorobenzene National Institute for Occupational Safety and Health (NIOSH) 4 December 2014 6 March 2015 19 March 2015 https://web.archive.org/web/20150319151735/http://www.cdc.gov/niosh/idlh/106467.html live 857 mg/kg (human, oral)4000 mg/kg (rat, oral)2800 mg/kg (guinea pig, oral) 1,2-Dichlorobenzene1,3-Dichlorobenzene 1,4-Dichlorobenzene (1,4-DCB, p-DCB, or para-dichlorobenzene, sometimes abbreviated as PDCB or para) is an aryl chloride and isomer of dichlorobenzene with the formula C6H4Cl2. This colorless solid has a strong sweet odor reminiscent of mothballs. The molecule consists of a benzene ring with two chlorine atoms (replacing hydrogen atoms) on opposing sites of the ring. It is used as a disinfectant, pesticide, and deodorant, most familiarly in mothballs in which it is a replacement for the more traditional naphthalene because of naphthalene's greater flammability (though both chemicals have the same NFPA 704 rating). It is also used as a precursor in the production of the chemically and thermally resistant polymer poly(p-phenylene sulfide). Rossberg M. Lendle W. Pfleiderer G. Tögel A. Dreher E. L. Langer E. Rassaerts H. Kleinschmidt P. Strack H. Cook R. Beck U. Lipper K.-A. Torkelson T.R. Löser E. Beutel K.K. Mann T. Chlorinated Hydrocarbons 2006 10.1002/14356007.a06_233.pub2 Production p-DCB is produced by chlorination of benzene using ferric chloride as a catalyst: C6H6 + 2 Cl2 → C6H4Cl2 + 2 HCl The chief impurity is the 1,2 isomer. The compound can be purified by fractional crystallization, taking advantage of its relatively high melting point of 53.5 °C; the isomeric dichlorobenzenes and chlorobenzene melt well below room temperature. Uses Disinfectant, deodorant, and pesticide thumb|1,4-dichlorobenzene balls sold as urinal disinfectant p-DCB is used to control moths, molds, and mildew. http://npic.orst.edu/capro/Mothballs1.pdf National Pesticide Information Center – Mothballs Case Profile 10 August 2009 https://web.archive.org/web/20100622021329/http://npic.orst.edu/capro/Mothballs1.pdf 22 June 2010 dmy-all It also finds use as a disinfectant in waste containers and restrooms and is the characteristic smell associated with urinal cakes. Its usefulness for these applications arises from p-DCB's low solubility in water and its relatively high volatility: it sublimes readily near room temperature. Precursor to other chemicals Nitration gives 1,4-dichloronitrobenzene, a precursor to commercial dyes and pigments.K. Hunger. W. Herbst "Pigments, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2012. 10.1002/14356007.a20_371 The chloride sites on p-DCB can be substituted with hydroxylamine and sulfide groups. In a growing application, p-DCB is the precursor to the high performance polymer poly(p-phenylene sulfide): Fahey D. R. Ash C. E. 10.1021/ma00015a003 Mechanism of poly(p-phenylene sulfide) growth from p-dichlorobenzene and sodium sulfide Macromolecules 24 15 4242 1991 1991MaMol..24.4242F upright=1.5|Synthesis of polyphenylensulfide As ceruminolytic agent 2% Paradichlorobenzene used as a ceruminolytic agent for the treatment of impacted earwax.Nair P. Golhar S. Baisakhiya N. Deshmukh P. T. Indian Journal of Otolaryngology and Head and Neck Surgery 2009 61 3 185–192 10.1007/s12070-009-0063-z 23120632 A comparative study of ceruminolytic agents 3449978 Recreational Use Recreational abuse of PDCB https://www.neurology.org/doi/10.1212/WNL.94.15_supplement.1955 Looking for Light: Paradichlorobenzene Toxicity in a 30 Year-Old Woman Following Long Term Ingestion of Mothballs (1955) Neurology 2020-04-14 94 2026-03-20 10.1212/WNL.94.15_supplement.1955 subscription has been described, usually through use of urinal cakes. It is typically huffed. Deaths have been recorded from abuse.previous reference only mentions mothballs being eaten September 2026 Environmental and health effects thumb|Shipping container of the substance, showing several hazard labels confirming the environmental hazard posed by the substance. p-DCB is poorly soluble in water and is not easily broken down by soil organisms. Like many hydrocarbons, p-DCB is lipophilic and will accumulate in fatty tissues if consumed by a person or animal. The United States Department of Health and Human Services (DHHS) and the International Agency for Research on Cancer (IARC) have determined that p-DCB may reasonably be anticipated to be a carcinogen.Preamble to the IARC Monographs https://web.archive.org/web/20160809225810/http://monographs.iarc.fr/ENG/Preamble/currentb6evalrationale0706.php 9 August 2016 definition of "Group 2B: Possibly carcinogenic to humans", the International Agency for Research on Cancer classification of this chemical This has been indicated by animal studies, although a full-scale human study has not been done.ToxFAQs for Dichlorobenzenes https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsLanding.aspx?id=703&tid=126 Toxic Substances Portal Agency for Toxic Substances and Disease Registry 24 May 2013 26 November 2020 https://web.archive.org/web/20201126191021/https://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=703&tid=126 live The United States Environmental Protection Agency (EPA) has set a target maximum contaminant level of 75 micrograms of p-DCB per liter of drinking water (75 μg/L), http://www.epa.gov/ogwdw000/contaminants/dw_contamfs/p-dichlo.html Consumer Factsheet on: PARA-DICHLOROBENZENE (p-DCB) 28 November 2006 10 August 2009 https://web.archive.org/web/20091006081817/http://www.epa.gov/ogwdw000/contaminants/dw_contamfs/p-dichlo.html 6 October 2009 but publishes no information on the cancer risk.https://www3.epa.gov/airtoxics/hlthef/dich-ben.html 1,4-Dichlorobenzene (para-Dichlorobenzene) US Environmental Protection Agency en 24 March 2016 4 April 2016 https://web.archive.org/web/20160404214242/https://www3.epa.gov/airtoxics/hlthef/dich-ben.html p-DCB is also an EPA-registered pesticide. http://www.epa.gov/oppsrrd1/REDs/para-dichlorobenzene-red-revised.pdf Reregistration Eligibility Decision for Para-dichlorobenzene December 2008 10 August 2009 https://web.archive.org/web/20090926200251/http://www.epa.gov/oppsrrd1/REDs/para-dichlorobenzene-red-revised.pdf 26 September 2009 The United States Occupational Safety and Health Administration (OSHA) has set a maximum level of 75 parts of p-DCB per million parts air in the workplace (75 ppm) for an 8-hour day, 40-hour workweek.https://www.osha.gov/dts/chemicalsampling/data/CH_232900.html Chemical Sampling – p-Diclorobenzine United States Department of Labor Occupational Safety & Health Administration 23 March 2016 31 July 2017 https://web.archive.org/web/20170731224645/https://www.osha.gov/dts/chemicalsampling/data/CH_232900.htmlhttp://nj.gov/health/eoh/rtkweb/documents/fs/0643.pdf Common Name: 1,4-DICHLOROBENZENE December 2005 New Jersey Department of Health and Senior Services 24 March 2016 4 April 2016 https://web.archive.org/web/20160404084953/http://nj.gov/health/eoh/rtkweb/documents/fs/0643.pdf live A mechanism for the carcinogenic effects of mothballs and some types of air fresheners containing p-DCB has been identified in roundworms.The nongenotoxic carcinogens naphthalene and para-dichlorobenzene suppress apoptosis in Caenorhabditis elegans Kokel David 14 May 2006 2 6 10.1038/nchembio791 16699520 338–345 Nature Chemical Biology 18402091 Due to its carcinogenic nature, use of paradichlorobenzene in the European Union is forbidden as an air freshener (since 2005) and in mothballs (since 2008). Biodegradation Rhodococcus phenolicus is a bacterium species able to degrade dichlorobenzene as its sole carbon source. Rehfuss M. Urban J. 10.1016/j.syapm.2005.05.011 Rhodococcus phenolicus sp. nov., a novel bioprocessor isolated actinomycete with the ability to degrade chlorobenzene, dichlorobenzene and phenol as sole carbon sources Systematic and Applied Microbiology 28 8 695–701 2005 16261859 2005SyApM..28..695R See also Air freshener Camphor Mothball References External links 0037 00 Mothball sniffing warning issued, BBC News, 27 July 2006 NIOSH Pocket Guide to Chemical Hazards, Centers for Disease Control and Prevention Category:Organochloride insecticides Category:IARC Group 2B carcinogens Category:Dichlorophenyl compounds