Household income and ethnic origin influence levels of exposure to air and noise pollution, but the pattern is complex. These are the results of a new study performed in London by a team of researchers from ISGlobal – an institution supported by the "la Caixa" Foundation -, King’s College London, the Imperial College of London and London University.
The unequal distribution of environmental impacts according to ethnicity or social, economic or demographic position is known as environmental inequality. Most studies regarding air and noise pollution exposure inequalities have been based on residential exposures, with very few examples evaluating personal exposures, for example those experienced when commuting on a daily basis.
The aim of this study, published in Environment International, was to quantify socioeconomic and ethnic inequalities in London regarding exposure to air pollution (residential plus personal exposure) and noise pollution (at residence and from different sources: traffic, trains and aircraft).
Using mobility data of 45,000 people – obtained from the London Travel Demand Survey between 2006 and 2010- the researchers estimated levels of air (PM 2.5 and NO2) and noise pollution.
The results show that the “association between the citizens’ socioeconomic level and a higher or lower exposure to air pollution were different when considering residential exposure versus personal exposure, including transport mode and duration”, explains Cathryn Tonne, ISGlobal researcher and first author of the study.
People with higher household incomes were less exposed to NO2 at their residence as compared to lower incomes, but had higher personal exposure due to a greater use of private transport and trip duration and moment (during rush hours).
In contrast, inequalities in road traffic noise exposure were generally small. However, people exposed to noise equal or superior to 50dB from aircrafts arriving to or leaving from Heathrow were white individuals with high income.
Cathryn Tonne underlines that these studies “have important implications regarding environmental justice and for the correct design and interpretation of this type of studies”.
Cathryn Tonne, Carles Milà, Daniela Fecht, Mar Alvarez, John Gulliver, James Smith, Sean Beevers, H. Ross Anderson, Frank Kelly. Socioeconomic and ethnic inequalities in exposure to air and noise pollution in London. Environment International. 2018 Mar 22;115:170-179. doi: 10.1016/j.envint.2018.03.023.