Air Pollution Now Strongly Linked to Mental Illness by Dr. Joseph Mercola for Mercola
Worldwide, 93% of children live in areas with air pollution at levels above World Health Organization (WHO) guidelines.1 Further, more than 1 in 4 deaths among children under 5 years is related to environmental risks, including air pollution.
When most people think about health risks linked to polluted air, respiratory issues come to mind and, indeed, in 2016 ambient (outside) and household air pollution contributed to respiratory tract infections that led to 543,000 deaths in children under 5.2 However, air pollution takes a toll on the whole body, contributing not only to physical risks but also mental health problems.
A set of studies by researchers at Cincinnati Children’s Hospital, in collaboration with researchers at the University of Cincinnati, has highlighted the risks to children, in particular, who may see their mental health suffer as a result of polluted air.
Three Studies Link Air Pollution to Mental Health Risks
In the first study, published in Environmental Health Perspectives, researchers looked at the association between emergency room visits and exposure to fine particulate matter (PM 2.5), which refers to dust, dirt, soot and smoke particles smaller than 2.5 micrometers in diameter.3
The WHO report revealed that in low- and middle-income countries, 98% of children under 5 years are exposed to fine particulate matter at levels higher than the WHO air quality guidelines.
The Environmental Health Perspectives study revealed that short-term exposure to air pollution was linked to increased utilization of the Cincinnati Children’s emergency department for psychiatric issues, particularly for adjustment disorder and suicidality.
Further, mental health of children living in high-poverty neighborhoods was most affected by air pollution. Lead study author Cole Brokamp, Ph.D., with Cincinnati Children’s Hospital, said in a news release:4
“This study is the first to show an association between daily outdoor air pollution levels and increased symptoms of psychiatric disorders, like anxiety and suicidality, in children. More research is needed to confirm these findings, but it could lead to new prevention strategies for children experiencing symptoms related to a psychiatric disorder.”
Air Pollution May Cause Brain Inflammation, Anxiety Symptoms
The second study, published in the August 2019 issue of Environmental Research, looked into exposure to traffic-related air pollution (TRAP) on brain metabolism and symptoms of generalized anxiety in 12-year-olds.5 Recent exposure to TRAP was associated with generalized anxiety symptoms and increased myo-inositol, a marker of inflammation in the brain.
“This is the first study of children to utilize neuroimaging to link TRAP exposure, metabolite dysregulation in the brain, and generalized anxiety symptoms among otherwise healthy children,” the researchers concluded. “TRAP may elicit atypical excitatory neurotransmission and glial inflammatory responses leading to increased metabolite levels and subsequent anxiety symptoms.”6
The third study, also published in Environmental Research, found that early-life exposure to TRAP, as well as exposure during childhood, was significantly associated with depression and anxiety symptoms in 12-year-olds.7 A similar association between air pollution and mental health was previously reported among adults, but this study suggests the effects may also occur in children exposed to air pollution.
“Collectively, these studies contribute to the growing body of evidence that exposure to air pollution during early life and childhood may contribute to depression, anxiety, and other mental health problems in adolescence,” Patrick Ryan, Ph.D., a lead author of the Environmental Health Perspectives study, said in a news release. “More research is needed to replicate these findings and uncover underlying mechanisms for these associations.”8
Past research has also found that living in an area with higher levels of air pollution is associated with decreased cognitive function and sleep disturbances.9
“Evidence that exposure to air pollution affects brain structure was found by magnetic resonance imaging (MRI) of participants in the Framingham Offspring Study, indicating that higher exposure to PM2.5 is associated with a reduction in total brain volume,” according to a Royal College of Physicians report.10