What’s happening? People recently diagnosed with psychotic/mood disorders may need mental health support more often if exposed to traffic-related air pollution, according to a British Journal of Psychiatry paper. Data from 13,887 people were followed for seven years following their first visit to a south London-based mental health service between 2008-2012. Every 3 mcg/m3 increase in PM2.5 and 15 mcg/m3 increase in nitrogen dioxide (NO2) over 12 months raised risks of an inpatient stay by 11% and 18%, respectively. PM2.5 and NO2 increases were also associated with 7% and 32% respective risks of needing community care. Findings were replicated over the seven-year follow-up. (University of Bristol – press release, British Journal of Psychiatry)

Brain drain – There is an increasing body of evidence showing that air pollution can have just as a significant impact on the brain as elsewhere in the body. In line with the above study, it’s been found that exposure to even small increases in air pollution in the urban environment can raise levels of anxiety and depression. It’s also been linked to poorer performance in pupils of schools located in highly polluted areas and office workerscan suffer as a result too. Cognitive function can also be affected by the use of solid fuels in the home.

Increased risk of neurodegenerative disorders, such as Alzheimer’s disease and other dementias (predicted to rise from an estimated 57 million cases to 152 million globally by 2050), have also been associated with air pollution. Alarmingly, the risk could even begin during childhood.

Indirect impact – We’re all well aware of the fact that air pollution is closely related to climate change, which is resulting in extreme weather events. In turn, these are also harming mental health. Hot weather, for example, is known to make people feel physically uncomfortable and more bad tempered, so it’s no surprise that increases in violent crime are observed when temperatures rise.

Natural disasters, including flooding, hurricanes, tornadoes, storms and wildfires, raise the risk of psychological issues such as depression, anxiety and post-traumatic stress disorder alongside suicide. Climate change-related insecurities about food, housing and income have also been associated with worsening mental health, while the prospect of its effect on the environment is damaging the wellbeing of young people.

What’s the solution? Part of the answer lies in providing more easily accessible mental health services and psychological interventions alongside reducing the stigma around using them. These alone, however, won’t solve the problem. Direct action is needed now to reduce air pollution and address all its negative impacts on the planet to prevent an even more dire situation in the future.