Editing Coal tar (section)

=== Construction ===
{{Main|Sealcoat}}

Coal tar was a component of the first sealed roads. In its original development by [[Edgar Purnell Hooley]], [[Tarmacadam|tarmac]] was tar covered with granite chips. Later the filler used was industrial [[slag]]. Today, petroleum derived binders and sealers are more commonly used. These sealers are used to extend the life and reduce maintenance cost associated with [[Asphalt concrete|asphalt]] pavements, primarily in asphalt road paving, car parks and walkways.{{citation needed|date=April 2021}}

Coal tar is incorporated into some parking-lot [[sealcoat]] products used to protect the structural integrity of the underlying pavement.<ref name="fs20113010">{{cite web| vauthors = Mahler BJ, Van Metre PC | url = http://pubs.usgs.gov/fs/2011/3010/| title = Coal-Tar-Based Pavement Sealcoat, Polycyclic Aromatic Hydrocarbons (PAHs), and Environmental Health| publisher = U.S. Geological Survey Fact Sheet| date = 2 February 2011| access-date = 8 March 2013| url-status = live| archive-url = https://web.archive.org/web/20130328042236/http://pubs.usgs.gov/fs/2011/3010/| archive-date = 2013-03-28}}</ref> Sealcoat products that are coal-tar based typically contain 20 to 35 percent coal-tar pitch.<ref name="fs20113010"/> Research<ref name=lakes>{{cite journal | vauthors = Van Metre PC, Mahler BJ | title = Contribution of PAHs from coal-tar pavement sealcoat and other sources to 40 U.S. lakes | journal = The Science of the Total Environment | volume = 409 | issue = 2 | pages = 334–44 | date = December 2010 | pmid = 21112613 | doi = 10.1016/j.scitotenv.2010.08.014 | bibcode = 2010ScTEn.409..334V }}</ref> shows it is used throughout the [[United States of America]], however several areas have banned its use in sealcoat products,<ref name=austin>{{cite web| url = http://www.austintexas.gov/sites/default/files/files/Watershed/coaltar_ordinance.pdf| title = City of Austin Ordinance 20051117-070| date = 17 November 2005| access-date = 8 March 2013| url-status = live| archive-url = https://web.archive.org/web/20130531014726/http://austintexas.gov/sites/default/files/files/Watershed/coaltar_ordinance.pdf| archive-date = 2013-05-31}}</ref><ref name=dc>{{cite web| title = District Bans Coal-Tar Pavement Products| url = http://newsroom.dc.gov/show.aspx/agency/ddoe/section/2/release/17479| date = 26 June 2009| access-date = 8 March 2013| url-status = live| archive-url = https://web.archive.org/web/20121226213006/http://newsroom.dc.gov/show.aspx/agency/ddoe/section/2/release/17479| archive-date = 2012-12-26}}</ref><ref name=dane>{{cite web| publisher = Dane County Office of Lakes and Watersheds| url = http://pdf.countyofdane.com/ordinances/ORD080.pdf| title = Ordinance 80 : Establishing Regulations on Coal Tar Sealcoat Products Application and Sale| date = 1 July 2007| access-date = 8 March 2013| url-status = live| archive-url = https://web.archive.org/web/20110824044232/http://pdf.countyofdane.com/ordinances/ORD080.pdf| archive-date = 2011-08-24}}</ref> including the District of Columbia; the city of Austin, Texas; Dane County, Wisconsin; the state of Washington; and several municipalities in Minnesota and others.<ref>{{cite web| title = Coal Tar Free America&nbsp;– Bans| url = http://coaltarfreeamerica.blogspot.com/p/bans.html| access-date = 8 March 2013| url-status = live| archive-url = https://web.archive.org/web/20141006095421/http://coaltarfreeamerica.blogspot.com/p/bans.html| archive-date = 2014-10-06}}</ref><ref name="EESI">{{cite conference| conference-url = http://www.eesi.org/pahs-increasing-urban-us-lakes-14-apr-2011| conference = PAHs Increasing in Urban U.S. Lakes| url = http://files.eesi.org/mahler_041411.pdf| title = Causes of Increasing Concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) in U.S. Lakes| vauthors = Mahler BJ | publisher = Environmental and Energy Study Institute| date = 14 April 2011| access-date = 8 March 2013| url-status = dead| archive-url = https://web.archive.org/web/20111005105420/http://files.eesi.org/mahler_041411.pdf| archive-date = 5 October 2011}}</ref>