Last week, Oxford City Council announced plans to enact the world’s first “zero-emission zone” (ZEZ) around Oxford city centre by 2020, hoping to further extend the region in coming years.The proposals come as a response to the illegally high levels of toxic NO2 found in many of the UK’s most populated cities. Oxfordshire Air Quality (OAQ) highlights that “twice as many people currently suffer from asthma today, compared with 30 years ago,” with a Public Health England study also estimating that illegal levels of NO2 have contributed to 5.3% of all deaths for over-25s in the UK. The Committee of the Medical Effects of Air Pollutants clarifies that “it is not plausible to think of the figure of ‘attributable’ deaths as enumerating an actual group of people whose death is attributable to air pollution alone i.e. the victims of outdoor air pollution” – rather a contribution that accelerates existing illness as well as affecting a much larger demographic through generally reducing wellness and increasing susceptibility.Continued inhalation of NO can cause inflammation in the lining of the lungs, leaving one susceptible to an array of respiratory diseases and eventually wearing down the lungs’ function.NO2 is formed once the nitrogen and oxygen in the air react under the high temperature inside an internal combustion engine. NO2 can decompose to NO, more commonly known as “laughing gas”, once it leaves the engine and interacts with sunlight.The European Union set a legal limit for emissions each – levels must not exceed 40 micrograms per cubic meter of air (µg/m3) of NO2 at on average. As of June 2017, of the 70 locations where Oxford City Council monitor levels of air pollution, 17 lie over the EU’s legal limit.High Street, the area targeted for the first stages of the ZEZ plans, had an average of 47 µg/m3. St Clements Street was the worst offender with NO2 levels at 61 µg/m3, though this was a decrease from 85 µg/m3 just five years ago.Oxford’s council have said that the ZEZ would ban “petrol and diesel cars, taxis, light commercial vehicles and busses”, with hopes to “cut the nitrogen dioxide level in Oxford city centre’s most polluted street, George Street, by 74% by 2035.”Levels of NO2 have been steadily declining due to the development of better catalytic converters, and the steady rise of electric cars – with levels about a quarter of what they were in 1970. However, many urban areas in the UK still lie far above the 40 µg/m3 limit. In 2016, government monitoring stations found that about 40% of local authorities breached the legal limit. This prompted the government to introduce an immediate implementation fund worth £255 million “to address poor air quality in the shortest time possible.” This implementation fund is also partly responsible for funding Oxford City Council’s efforts.The introduction of a zero-emission zone in Oxford is a bold initiative that serves as an example to other cities. On balance, Oxford has the resources and geography to enact a ZEZ with the least amount of significant adverse effects.Air quality affects us every day. Hopefully, taking quick and decisive steps to combat air pollution can lead the way to tackle similar issues such as global warming, whose effects are considered less immediate and seem far removed from our everyday experience.You can find the current levels of air pollution in Oxford here.