TOPLINE
Exposure to higher levels of air pollution can possibly lead to an increased risk of serious mental health issues, according to research published in the British Journal of Psychiatry, adding to growing research highlighting the hidden health costs of the climate crisis.
A factory at sunset in Cleveland, Ohio.
KEY FACTS
Patients with psychotic and mood disorders like schizophrenia, bipolar and depression who had greater exposure to air pollution were more likely to be hospitalized or need community-based treatment for their conditions than those who did not, researchers from King’s College London and Imperial College London found.
Higher levels of nitrogen dioxide at peoples’ homes led to a higher risk of them needing mental health treatment, the researchers found, and more modest increases were observed for other common pollutants like nitrogen oxides and particulate matter.
People exposed to a 15 micrograms per cubic meter (µg/m³) increase in nitrogen dioxide levels over one year—the average in the study was 40µg/m³—had an 18% higher risk of being admitted to hospital and 32% higher change of needing outpatient care, the researchers found after examining the medical records of nearly 14,000 patients in London.
The researchers also found that an increase in small particulate matter of 3µg/m³ over the course of a year—the average was 14.5µg/m³—led to an increased risk of 7% for outpatient care and 11% for hospital treatment.
The link remained seven years later when the scientists assessed the records of the same patients and the researchers said there does not seem to be another explanation for the phenomenon, though they do not rule one out.
The study, while based on a specific part of London, likely applies to cities around the world, the researchers said, as the area studied reflects not only the air pollution patterns for the whole of London but those in “all large cities with heavy diesel vehicle traffic.”
CRUCIAL QUOTE
“The environmental and climate emergency is also a mental health emergency,” said Dr Adrian James, President of the Royal College of Psychiatrists. “If air pollution is exacerbating pre-existing serious mental illnesses, such as schizophrenia, bipolar disorder and major depression, then improving air quality could reduce the pressure on mental health services,” he said.
KEY BACKGROUND
While the study does not—and cannot, being an observational study—demonstrate a causal link between pollution and mental illness, it adds to growing research that suggests toxins in the air can have profound effects on our minds. Higher instances of suicide, depression and schizophrenia have been linked to air pollution. Long term exposure has been linked with reduced cognitive intelligence, especially among men. This adds to the significant physical damage pollution can cause—it could be affecting every part of the human body—which ranges from breathing problems to skin issues. Beyond the physical effects, the climate crisis itself is inducing anxiety and fear in growing numbers of—notably young—people.