Editing Cycling (section)

===Exposure to air pollution===
One concern is that riding in traffic may expose the cyclist to higher levels of air pollution, especially cyclists regularly traveling on or along busy roads. Some authors have claimed this to be untrue, showing that the pollutant and irritant count within cars is consistently higher,<ref>{{cite journal |doi=10.1071/HE04063 |last1=Chertok |first1=Michael |last2=Voukelatos |first2=Alexander |last3=Sheppeard |first3=Vicky |last4=Rissel |first4=Chris |year=2004 |title=Comparison of air pollution exposure for five commuting modes in Sydney – car, train, bus, bicycle and walking |journal=Health Promotion Journal of Australia |volume=15 |issue=1 |pages=63–7 |url=http://vadebike.org/wp-content/uploads/2008/08/Comparison-of-air-pollution-exposure-for-five-commuting-modes-in-Sydney-car-train-bus-bicycle-and-walking-HPJA.pdf |access-date=1 February 2016 |archive-url=https://web.archive.org/web/20160205085716/http://vadebike.org/wp-content/uploads/2008/08/Comparison-of-air-pollution-exposure-for-five-commuting-modes-in-Sydney-car-train-bus-bicycle-and-walking-HPJA.pdf |archive-date=5 February 2016 |url-status=dead}}</ref> presumably because of limited circulation of air within the car and due to the air intake being directly in the stream of other traffic. Other authors have found small or inconsistent differences in concentrations but claim that exposure of cyclists is higher due to increased minute [[ventilation (physiology)|ventilation]]<ref>{{cite journal |doi=10.1016/j.atmosenv.2010.04.028 |title=Exposure to particulate matter in traffic: A comparison of cyclists and car passengers |journal=Atmospheric Environment |volume=44 |issue=19 |pages=2263–2270 |year=2010 |last1=Int Panis |first1=Luc |last2=De Geus |first2=Bas |last3=Vandenbulcke |first3=Grégory |last4=Willems |first4=Hanny |last5=Degraeuwe |first5=Bart |last6=Bleux |first6=Nico |last7=Mishra |first7=Vinit |last8=Thomas |first8=Isabelle |last9=Meeusen |first9=Romain |bibcode=2010AtmEn..44.2263I |s2cid=56142753}}</ref> and is associated with minor biological changes.<ref>{{cite journal |doi=10.1186/1476-069X-9-64 |pmid=20973949 |pmc=2984475 |title=Subclinical responses in healthy cyclists briefly exposed to traffic-related air pollution: An intervention study |journal=Environmental Health |volume=9 |pages=64 |year=2010 |last1=Jacobs |first1=Lotte |last2=Nawrot |first2=Tim S |last3=De Geus |first3=Bas |last4=Meeusen |first4=Romain |last5=Degraeuwe |first5=Bart |last6=Bernard |first6=Alfred |last7=Sughis |first7=Muhammad |last8=Nemery |first8=Benoit |last9=Panis |first9=Luc |issue=1 |doi-access=free|bibcode=2010EnvHe...9...64J }}</ref> A 2010 study estimated that the gained life expectancy from the health benefits of cycling (approximately 3–14 months gained) greatly exceeded the lost life expectancy from air pollution (approximately 0.8–40 days lost).<ref name=":0" /> However, a systematic review comparing the effects of air pollution exposure on the health of cyclists was conducted, but the authors concluded that the differing methodologies and measuring parameters of each study made it difficult to compare results and suggested a more holistic approach was needed to accomplish this.<ref>{{Cite journal |last1=Raza |first1=Wasif |last2=Forsberg |first2=Bertil |last3=Johansson |first3=Christer |last4=Sommar |first4=Johan Nilsson |date=5 February 2018 |title=Air pollution as a risk factor in health impact assessments of a travel mode shift towards cycling |journal=Global Health Action |volume=11 |issue=1 |pages=1429081 |doi=10.1080/16549716.2018.1429081 |issn=1654-9716 |pmc=5804679 |pmid=29400262}}</ref> The significance of the associated health effect, if any, is unclear but probably much smaller than the health impacts associated with accidents and the health benefits derived from additional physical activity.