A landmark ten-year study of the impact of exposure to London’s air pollution suggests that children growing up in the capital are at risk of developing lifelong breathing disorders.
And, researchers behind the study have suggested that the findings demonstrate the need for conintued focus from policy makers on measures to address sources of air pollution.
The study, which was led by researchers from King’s College London, Queen Mary University of London and the University of Edinburgh and published in Lancet Public Health today, suggests that measures enacted in the capital since 2008 have improved air pollution, but ‘significant’ improvements will be needed to protect children’s health.
2,164 children aged 8-9 were enrolled into the study from 28 primary schools in the London boroughs of Tower Hamlets, Hackney, Greenwich and the City of London – areas which fail to meet current EU nitrogen dioxide limits.
The research team monitored children’s health and exposure to air pollutants over five years, covering the period when the London Low Emission Zone (LEZ) was introduced.
Findings suggested that children exposed to air pollution showed significantly smaller lung volume (a loss of approximately 5% in lung capacity). This was linked to annual exposures of nitrogen dioxide (NO2) and other nitrogen oxides (NOx), both of which are in diesel emissions, and particulate matter (PM10), the researchers said.
Following the implementation of London’s LEZ, there were small improvements in NO2 and NOx levels, but no improvements in PM10, the team found.
Despite improvements in air quality, there was no evidence of a reduction in the proportion of children with small lungs or asthma symptoms over this period.
Additionally, the percentage of children living at addresses exceeding the EU limit for NO2 fell following the LEZ introduction, from 99% in 2009 to 34% in 2013, the study noted, but they were exposed to higher levels when at school, many of which were next to busy roads.
Commenting on the findings, Dr Ian Mudway, lecturer in respiratory toxicology at King’s College London, said: “There is an urgent need to improve our air quality, especially within our congested cities. Policies such as the Low Emission Zone strive to do this, but their effectiveness needs careful and objective evaluation, not only in terms of whether they improve air quality, but more importantly, whether they deliver better health.
“As the evidence base grows demonstrating that air pollution impacts on the health of children born and growing up in our cities, so the justification for decisive action increases.”
Professor Frank Kelly, director of King’s College’s Environmental Research Group, added: “These new findings linking air pollution and children’s lung growth provide further support for the introduction of the Ultra-Low Emission Zone in London early next year.”
Professor Chris Griffiths from Queen Mary University of London, said: “Despite air quality improvements in London, this study shows that diesel-dominated air pollution in cities is damaging lung development in children, putting them at risk of lung disease in adult life and early death.
“We are raising a generation of children reaching adulthood with stunted lung capacity. This reflects a car industry that has deceived the consumer and central government which continues to fail to act decisively to ensure towns and cities cut traffic.”
The study is a collaboration across the MRC Asthma UK Centre in Allergic Mechanisms of Asthma and the Asthma UK Centre for Applied Research, and was funded by NHS Hackney, the NIHR Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London with donations from Him Lee and the Felicity Wilde Charitable Trust.