New review highlights the impact of air quality on mental health

At yesterday’s Clean Air Networks Conference in Birmingham, Professor Kam Bhui from the University of Oxford spoke in an afternoon session for which the theme was ‘Health and Inequalities’. Kam’s personal contribution was titled ‘Air quality and mental health: evidence, challenges and future directions’.

Today, review of evidence research, compiled by a team led by Kam, has been published in the British Journal of Psychiatry revealing that poor air quality can impact mental health in a number of ways.

The purpose of the review was to pull together a wide range of research that has taken place around this subject, to summarise what is currently known and identify areas in which more research might be undertaken. 

For example, the team found that a lot of good research had taken place establishing a link between particulate matter and depression but less on psychoses, and specific conditions such as schizophrenia or personality disorders. 

Of the research that has been carried out in that field the review cites a 2019 study that revealed that among 2063 adolescents, psychotic experiences were significantly more common among adolescents with the highest level of annual exposure to nitrogen dioxide and PM_2.5

Professor Bhui said: ‘Our review shows that there is emerging evidence of links between poor air quality and poor mental health, as well as links to specific mental disorders.

‘In particular, polluting air particles, including bioaerosols, have been implicated. Particulate matter forms part of a complex set of environmental risk factors including geography, deprivation, biology and individual vulnerabilities.

‘We need more research to understand these webs of causation and to investigate a number of other critical knowledge gaps such as the mechanisms by which particles matter and bioaerosols may cause and worsen health conditions. There is less research on indoor air quality and how it affects health, and little on bioaerosols specifically.

‘We need better ways to measure exposure to pollution and understand how climate change affects air pollution. We also call for more longitudinal studies to understand the effects on children and young people as they grow.’

‘Modifying exposure to poor air quality indoors and outdoors could reduce levels of poor health in general.

‘But, given the high levels of serious mental illness in places where air pollution is greatest, in poorer and urban areas especially, and the links between, for example, cancer and serious mental illness, there may be common causes and risk factors that need to be understood and addressed.’

The report can be read here.