Air Pollution Claimed Can Aggravate Human Mental Illness

Air pollution can cause dementia. (photo: Marcin Jozwiak / Unsplash)

JAKARTA - Apart from climate change, air pollution also has a significant impact on human mental illness. Researchers in London, England found it can also cause a decline in intelligence and memory, called dementia.

The findings were published in the British Journal of Psychiatry as quoted by The Guardian, Tuesday, August 31. The researchers started by tracking patients in South London based on the first report with mental health services on 13,000 people. They used high-resolution estimates of air pollution in the patient's home.

With so many people being admitted to the hospital, or making visits to the doctor due to mental illness, the researchers took advantage of this incident and said it occurred mostly in cities in developed countries.

Quarterly average NO2 levels in the London study area varied between 18 and 96 micrograms per cubic meter (µg/m³). The researchers found people exposed to pollution levels of 15µg/m³ had an 18 percent higher risk of being hospitalized, and 32 percent required one year of outpatient care due to mental health.

Furthermore, brain cells called microglia can become inflamed in response to pollution. So the higher the inflammation of the microglia can increase the risk of mental health disorders later in life. The most powerful NO2 pollution comes mostly from diesel-engined vehicles.

Newbury added, it is not easy for people to avoid pollution. Moreover, it reduces air pollution in cities. Of course the solution urgently requires communal action on a large scale.

“Air pollution is exacerbating mental health conditions in crowded cities. But actually, air pollution can be modified, even on a large scale. Reducing population-level exposure is hugely beneficial," said University of Bristol researcher Joanne Newbury.

In addition, the researchers assessed patient data again seven years after the first treatment and found the association with air pollution was still evident. This finding was not explained by a range of other possible factors including age, sex, ethnicity, deprivation or population density, although unidentified factors may still play an important role.

"Identifying modifiable risk factors for disease severity and relapse could inform early intervention efforts and reduce the human suffering and high economic costs caused by long-term chronic mental illness," the researchers said.

Minor developments in air pollution contributed to significant increases in depression and anxiety. Ironically, dirty air can also be the cause of someone committing suicide because mental disorders are getting worse. It makes biological sense, as air pollutants are known to have strong inflammatory properties to the brain, and are believed to be a factor in psychotic and mood disorders.