The introduction of the Low Emission Area (LEZ) in London has led to slight improvements in air quality but was not associated with a reduction in the proportion of children with reduced lung volumes for their age, according to an observational study.
Researchers who write Lancet public health said that interventions are needed to improve the health of children, which have resulted in greater emission reductions.
Experts said that the findings underlined that public health policies were aimed at reducing general levels of air pollution, and therefore more targeted initiatives were needed to protect the health of vulnerable people, such as children and older adults.
A study run by Queen Mary University of London (QMUL) and King's College London (KCL) included 2164 children between the ages of 8 and 9 who attended 28 primary schools in four city districts in London . Tower Hamlets, Hackney, Greenwich and the city of London were selected because they were not in compliance with the European Union of nitrogen dioxide (NO2) the boundary at the start of the study.
Between 2009-10 and 2013-2014, participants received annual winter medical examinations, which included volumetric measurements and lung function with spirometry. Parents were asked to complete a medical history questionnaire for their child.
Reduction in lung capacity
Researchers found that children exposed to air pollution lost about 5% in lung capacity. This was associated with annual exposure to NO2 and other nitrogen oxides (NOx) – both in the emissions of diesel fuels – and in particulate matter (PM10).
After the introduction of the London LEZ, there were small improvements in NO2 and NOx but there are no improvements in PM10 she showed the study.
"What we can not see in these children was an improvement in pulmonary function, said interlocutor Ian Mudway, a professor of respiratory toxicology at KCL, Medscape News UK. "Although air pollution has improved, it has not improved to see a signal in terms of the health of these children."
Other factors that could affect respiratory health, including age, gender, height, body mass index, ethnicity, socio-economic status and exposure to tobacco smoke in the environment, were taken into account.
Researchers found that: "Large LEZs can improve air quality in cities and can be linked to changes in respiratory health during childhood.
"However, more ambitious schemes than those assessed here are needed to meet legal constraints and improve the health of the respiratory tract in many European cities."
Co-author Prof Chris Griffiths from QMUL said: "Despite diesel vehicles that emit higher levels of pollutants in the real world, some improvements have been made than in the tests.
"Nevertheless, many areas of the interior and exterior of London still violate the EU's air pollution standards and are unlikely to achieve them without a significant tightening of current emission controls."
Dr. Mudway said: "How the lungs develop, or reach their greatest growth in adulthood, is crucial in terms of life expectancy, healthy life levels in later life, and so, says that there are now effects in our population that could affect the quality of their lives, the length of their lives, many years on the river. "
Invitation to the new rules on air pollution
Dr. Stefan Reis, head of atmospheric chemistry and effects at the Center for Ecology and Hydrology commented on the research: "This study highlights the key challenge for carrying out policy interventions to improve air quality.
"So far, there has been a great deal of emphasis on achieving air quality limit values at several existing air quality monitoring sites. However, the planned measures to reduce the exposure of the population in urban areas and, in particular, [in] vulnerable groups, such as children or older adults, should be properly assessed before implementation. "
Shirley Rodrigues, Deputy Mayor for Environment and Energy at the London Mayor's office, commented: "This shocking report is yet another proof of how pollution threatens the lives of young Londoners. The mayor and I have not ignored this public health crisis and are already firm in action. "
The County Office said it would introduce the first world-wide area with extremely low emissions in April 2019 in order to further reduce air pollution in the heart of London.
A representative of the Food, Environment and Rural Affairs Department (DEFRA) said: "Although the UK's air quality has improved significantly since 2010, we understand the risks that it continues to pose for human health and meet greater needs.
"For this reason, we have introduced a plan to reduce the harmful emissions of £ 3.5 billion and an ambitious clean air strategy that was welcomed by the World Health Organization."
"Soon we will go further with the new legislation in order for the local government to give new powers to act in areas with pollution."
The influence of the low-emission low-emission zone on air quality and childhood respiratory health: a consecutive annual cross-sectional study, Mudway et al, The Public Health Lancet. Paper.