Editing Tire (section)

===Environmental issues===
[[File:Tyre fire.jpg|thumb|Toxic fumes emerging from a fire at a tire dump.|upright]]
Americans generate about 285 million scrap tires per year.<ref>{{cite web|url= http://www.epa.gov/waste/conserve/materials/tires/tdf.htm |title=Tire-Derived Fuel |publisher=U.S. Environmental Protection Agency |access-date=2011-12-29}}</ref> Many states have regulations as to the number of scrap tires that can be held on-site, due to concerns with dumping, fire hazards, and mosquitoes. In the past, millions of tires have been discarded into open fields. This creates a breeding ground for mosquitoes, since the tires often hold water inside and remain warm enough for mosquito breeding. Mosquitoes create a nuisance and may increase the likelihood of spreading disease. It also creates a fire danger, since such a large tire pile is a lot of fuel. Some [[tire fire]]s have burned for months, since water does not adequately penetrate or cool the [[burning tires]]. Tires have been known to liquefy, releasing hydrocarbons and other contaminants to the ground and even groundwater, under extreme heat and temperatures from a fire. The black smoke from a tire fire causes air pollution and is a hazard to downwind properties.

The use of scrap tire chips for landscaping has become controversial, due to the leaching of metals and other contaminants from the tire pieces. Zinc is concentrated (up to 2% by weight) to levels high enough to be highly toxic to aquatic life and plants.<ref>{{cite web|url= http://www.ardeacon.com/pdf/Assessment_Environmental_Toxicity_Report.pdf |title=An Assessment of Environmental Toxicity and Potential Contamination from Artificial Turf using Shredded or Crumb Rubber |last=Sullivan |first=Joseph P. |year=2006 |access-date=2009-06-01 |archive-date=16 August 2009 |archive-url= https://web.archive.org/web/20090816063708/http://www.ardeacon.com/pdf/Assessment_Environmental_Toxicity_Report.pdf|url-status=dead}}</ref> Of particular concern is evidence that some of the compounds that leach from tires into the water contain hormone disruptors and cause liver lesions.<ref>{{cite web|url= https://puyallup.wsu.edu/wp-content/uploads/sites/403/2015/03/rubber-mulch.pdf |title=The Myth of Rubberized Landscapes |last=Chalker-Scott |first=Linda |archive-url= https://web.archive.org/web/20091007125638/http://www.puyallup.wsu.edu/~Linda%20Chalker-Scott/Horticultural%20Myths_files/Myths/Rubber%20mulch.pdf |archive-date=2009-10-07 |url-status=live |access-date=2009-06-01}}</ref>

Tires are a major source of [[Microplastics|microplastic]] pollution, found in a 2020 study to contribute 78% of the total mass of microplastics found in the ocean.<ref>{{cite web|url= https://www.sciencenews.org/article/car-tires-and-brake-pads-produce-harmful-microplastics |title=Car tires and brake pads produce harmful microplastics |date=2018-11-12 |work=Science News |access-date=2019-10-06}}</ref><ref>{{Cite news |last=LaBrecque |first=Sarah |date=2023-07-17 |title=Rising microplastics in seas puts pressure on tyre industry |url=https://www.reuters.com/sustainability/land-use-biodiversity/rising-microplastics-seas-puts-pressure-tyre-industry-2023-07-17/ |access-date=2025-01-15 |work=[[Reuters]]}}</ref> The commonly-used compound [[6PPD|6PPD-quinone]], found entering stormwater runoff via tire-wear particles, has been identified as toxic to coho salmon, brook trout, and rainbow trout.<ref>{{Cite journal |last1=Tian |first1=Zhenyu |last2=Zhao |first2=Haoqi |last3=Peter |first3=Katherine T. |last4=Gonzalez |first4=Melissa |last5=Wetzel |first5=Jill |last6=Wu |first6=Christopher |last7=Hu |first7=Ximin |last8=Prat |first8=Jasmine |last9=Mudrock |first9=Emma |last10=Hettinger |first10=Rachel |last11=Cortina |first11=Allan E. |last12=Biswas |first12=Rajshree Ghosh |last13=Kock |first13=Flávio Vinicius Crizóstomo |last14=Soong |first14=Ronald |last15=Jenne |first15=Amy |date=2021-01-08 |title=A ubiquitous tire rubber–derived chemical induces acute mortality in coho salmon |url=https://www.science.org/doi/10.1126/science.abd6951 |journal=Science |volume=371 |issue=6525 |pages=185–189 |doi=10.1126/science.abd6951|pmid=33273063 |bibcode=2021Sci...371..185T }}</ref>