Air pollution is the main environmental cause of death and traffic, housing and the agricultural sector turn out to be the main contributors to mortality associated with air pollution in European cities.
This is the main conclusion of a study led by the Barcelona Institute for Global Health (ISGlobal), a center promoted by the “la Caixa” Foundation, which has calculated which are the sources that contribute the most to mortality associated with two air pollutants - PM2.5 particles and nitrogen dioxide (NO2)- in 857 European cities.
Among the cities studied are Barcelona, Madrid, Malaga, Murcia, Palma, Santiago de Compostela, Seville, Valencia, Valladolid and Zaragoza. The results of this research, published this Friday in the journal 'The Lancet Public Health', show great variability between the different cities studied and suggest that, since each one has its particularities and its own sources of air pollution, the strategies to improve air quality should be adapted to each local context.
If the data from the 857 cities are grouped together, the figures show that the source that contributes the most to mortality associated with PM2.5 particles are the emissions generated by homes, with an average contribution of 22.7% in all cities. , ahead of the livestock sector (18.0%), industry (13.8%), transportation (13.5%), the energy sector (10.0%), natural sources (8.8%) and maritime transport (5.5%).
“If we look at the combination of NO2 and PM2.5, traffic continues to be the sector with the greatest weight both in poor air quality and in mortality associated with it. However, if we look exclusively at mortality associated with PM2.5 particles, we see a significant contribution from the residential sector and the agricultural sector”, observes Sasha Khomenko, ISGlobal researcher and first author of the study.
Khomenko indicates that "most of the particles generated in the domestic environment are mainly due to the burning of biomass and coal for heating and, to a lesser extent, systems based on fossil fuels to generate heat and hot water and gas stoves ”.
“We are aware that the increase in the prices of fossil fuels and climate change mitigation policies have led to an increase in the use of biofuels. However, the fact that these are products of natural origin does not mean that they are not harmful to health ”, he adds.
Regarding agriculture, Khomenko stresses that "it is known that intensive livestock farming is an important source of particles that are generated mainly from the ammonia present in animal manure and also through the use of certain fertilizers." “It is a source of pollution that spreads from its place of origin and moves towards the cities that are in the vicinity”, he clarifies.
PM2.5 particles are the air pollutant with the greatest negative impact on mortality in European cities. The scientific team emphasizes that more research is needed to determine which of the components of these particles are most harmful to health.
Regarding mortality from NO2, there is a very prominent contributor, which is the transport sector, with an average contribution of 48.5% among all cities, ahead of industry (15.0%), the energy sector (14.7%), housing (10.3%) and maritime transport (9.7%).
NO2 is a gas that is generated in combustion processes, mainly from motorized vehicles, but also in industrial or power generation facilities.
“Bolder measures are needed to drastically reduce pollution and deaths associated with traffic, which remains the main source of emissions. And, at the same time, implement policies to mitigate the other sources of emissions of both NO2 and PM2.5, such as: regulating emissions from industries and maritime transport and limiting the burning of biomass in the domestic and emissions in the agricultural and livestock sector”, says Mark Nieuwenhuijsen, director of the Urban Planning, Environment and Health Initiative at ISGlobal.
