The World Health Organisation (WHO) recently ranked air pollution as the major environmental cause of premature death. Researchers from King’s College London, Imperial College London and University of Leicester, sought to analyze the potential health and societal costs of poor mental health in relation to air quality.
Researchers analysed data collected over five years from 1,600 Southwark and Lambeth adults to assess for common mental disorders, psychotic experiences and physical symptoms indicative of mental distress.
Mental and physical health data from the survey were linked with quarterly average concentrations of air pollution at the inner-city residential address of the participants. Air pollution includes gases such as nitrogen dioxide (NO2) amd microscopic solid and liquid particulate matter (PM) that originating from industry activity, transportation, and diesel exhaust fumes.
The researchers found a correlation between increases in particulate matter (PM2.5), increases in nitrogen dioxide (NO2), and the probability of mental disorders including a 200% increase in mental disorder cases with exposures to PM2.5 above 15.5 micrograms per cubic meter (below the EU value air quality target value of 25). Common mental disorders comprise different types of depression and anxiety.
The study also found an association between exposure to air pollution (PM10) and increased chance psychotic experiences.
"The findings suggest that people exposed to high levels of air pollution over a long-period of time are more likely to experience poor mental health. Air pollution is not the only factor that may have an impact on the presence of mental disorders, but it is a preventable one." – Dr Ioannis Bakolis, lead author and Senior Lecturer in Biostatistics and Epidemiology, Institute of Psychiatry, Psychology & Neuroscience (IoPPN), King’s College London