June 2, 2022

expert reaction to observational study on road traffic noise pollution at school and children’s cognition

An observational study published in PLOS Medicine looks at exposure to road traffic noise and cognitive development in schoolchildren in Barcelona.

Prof Anna Hansell, Professor of Environmental Epidemiology, University of Leicester, said:

“This is a carefully conducted study. The findings are consistent with the evidence on aircraft noise at schools, showing that higher levels of noise impact on reading comprehension and hyperactivity.  As well as road noise levels, the present study looked at variability in noise and found that higher variability also impacts on learning and attentiveness. This makes sense as it may be possible to ‘tune out’ a constant level of background noise but there is an innate response to sudden changes in noise levels that are likely to affect concentration.” 

Prof Iroise Dumontheil, Professor of Cognitive Neuroscience, Centre for Brain and Cognitive Development, Birkbeck, University of London, said:

“This carefully designed study carried out in Barcelona provides convincing evidence of a negative impact of traffic noise on the development of primary school children’s cognition.  Higher average noise and greater fluctuations in noise near schools and/or inside the classroom were associated with a slower improvement in attention and working memory over the course of a year, skills that are important for academic achievement. Strengths of the studies are the large number of children, the pairing of matched low/high noise schools, repeated assessments over a year, and the range of variables controlled for. Considering that many European children living in large cities are exposed to high road traffic noise levels, this study has implications for public policy to reduce road traffic noise near schools.”

Prof Trevor Cox, Professor of Acoustic Engineering, University of Salford, said:

Does the press release accurately reflect the science?

“Yes

Is this good quality research?  Are the conclusions backed up by solid data?

“Yes and yes

How does this work fit with the existing evidence?

“A few previous studies have established that environmental noise causes problems with learning in schools. This new paper adds further evidence that we need to tackle noise in schools.

Have the authors accounted for confounders?  Are there important limitations to be aware of?

“The authors have been careful to deal with confounding factors such as social economic status, but like all correlation studies, there is a risk a confounding factor being missed that could explain results. However, there have been other direct experimental studies that have exposed students to noise and measured attainment on tasks while the noise is playing, which have shown how noise impairs attainment in the short term. Consequently, it is believable that the correlation finding is created by causation via noise.

What are the implications in the real world?  Is there any overspeculation?  

“No overspeculation.

“Road traffic noise is a side effect of modern living. The fact it harms health and well-being is not talked about often enough. Arguably, the effect of noise on student learning in schools is the worst harm of environmental noise. This is because any lack of attainment is detrimental to health and well-being for the rest of the students’ lives. Addressing noise is particularly important for equality, because schools in disadvantaged areas are usually on noisier sites.”

‘Exposure to road traffic noise and cognitive development in schoolchildren in Barcelona, Spain: A population-based cohort study’ by Maria Foraster et al. was published in PLOS Medicine at 19:00 UK time on Thursday 2^nd June.

DOI: https://doi.org/10.1371/journal.pmed.1004001

Declared interests

Prof Iroise Dumontheil: “I am a collaborator on the Study of Cognition, Adolescents and Mobile Phones, within which we are planning to study similar issues in adolescence (https://scampstudy.org/) and I have a child who goes to primary school in London, a noisy city.”

Prof Trevor Cox:  “I have no conflicts of interest commenting on this.”

No others received.