Childhood Exposure To Air Pollution Linked To Cognitive Problems, Anxiety: Studies

New research suggests that exposure to air pollution may can increase the likelihood of children suffering from anxiety and reduce cognitive function.

Two new studies were published this month, which focus on air pollution exposure during childhood, and highlight the impact it may have on a child’s thinking and ability to reason.

The first study, published May 9 in the journal Environmental Health Perspectives, includes data from the Brain Development and Air Pollution Ultrafine Particles in School Children (BREATHE) Project. Researchers estimated residential exposure levels of particulate matter 2.5 during a woman’s prenatal period and the first seven years of a child’s life. This included more than 2,220 children from Barcelona, Spain.

Participants completed computerized tests assessing working memory, attentiveness, and conflict network during four visits in 2012 and 2013.

Researchers noted exposure to higher levels of PM 2.5 were linked to a decrease in working memory and a reduction in attention and focus. PM 2.5 is made up of ultra-fine particles of soot, dirt, and dust smaller than 2.5 micrometers. In comparison, one strand of human hair is roughly 70 micrometers.

Increases of PM 2.5 by 10 μgm3 resulted in a 20-point reduction in working memory. It also led to an increase in the conflict attentional network of 11 milliseconds, which is an indicator of poor cognitive performance.

The second study, published in the journal Environmental Research, focused on air pollution from traffic, examining exposure over the lifetime of 145 children with an average age of 12. Recent exposure in the past 12 months before testing was also conducted.

The children underwent an MRI and brain metabolites were measured. Anxiety symptoms were assessed using the Spence Children’s Anxiety Scale.

The data indicated an association with recent traffic air pollution exposure and increased myo-inositol with heightened anxiety symptoms. The central nervous system is particularly vulnerable to air pollution.

Myo-inositol is a naturally occurring metabolite found in specialized brain cells known as glial cells that assist with maintaining cell volume and fluid balance in the brain. It also helps to regulate hormones and insulin. Increases in myo-inosital can lead to high levels of inflammation and affect the various processes linked to the metabolite.

Researchers determined traffic pollution may cause increased inflammation in the brain leading to a change in neurochemistry, causing anxiety symptoms.

This isn’t the first study to indicate air pollution affects the emotional functions of children.  Another study published the year linked air pollution exposure to increased risk of psychosis in teens.

Prior research also linked exposure to air pollution during pregnancy to increased risk of autism and accelerated aging in children.

Both of the new studies emphasize findings suggesting exposure to air pollution during pregnancy and during the first years of life can greatly impact a child’s mental and emotional well-being. Researcher warn It may be a threat to neurodevelopment and could lead to a lifetime of difficulty, which is why efforts to reduce exposure and reduce air pollution levels in the environment is key.