As we move into the 21st century, it is becoming increasingly clear that the air we breathe affects us on more than just our lungs. In a new study from the University of Southern California (USC), experts found that a particular component of air pollution is associated with poor learning and memory in children. The same ingredient is also associated with Alzheimer’s disease and dementia in adults.

PM2.5 and its components

So what is this disturbing part of our air? It is most commonly known as PM2.5. It belongs to solid particles with a diameter of less than 2.5 micrometers. These particles are a mixture of dust, soot, organic compounds and metals.

Due to their small size, PM2.5 particles in polluted air can penetrate deep into our lungs, cross the blood-brain barrier, and potentially cause serious memory and health problems.

A particular component of PM2.5 called ammonium nitrate has caught the attention of scientists. It is formed as a result of the reaction in the atmosphere of ammonia formed as a result of agricultural activities and nitric acid formed as a result of burning fossil fuels.

The effect of air pollution on memory

The study was led by Megan Gerting, an associate professor of population and public health at the Keck School of Medicine at USC.

“Our study highlights the need for detailed investigation of particulate matter sources and chemical constituents,” Herting said. he said. “This suggests that understanding these nuances is critical for informing air quality regulations and understanding long-term neurocognitive effects.”

How did this work come about? Herting spent several years working with data from the largest brain study in America, known as the Adolescent Brain Development Study (ABCD). The aim of the study was to understand the potential effects of polluted air on the brain.

Sources of pollution

The main source of PM2.5 is the burning of fossil fuels, especially in urban areas. But other sources such as forest fires, agriculture, marine aerosols and chemical reactions also play an important role.

Herting and his team previously investigated the general effects of PM2.5 on children’s cognitive function and found no significant link.

In this latest study, the team used statistical techniques to look individually at 15 chemical components of PM2.5 and their sources. That’s when ammonium nitrate, a chemical compound often resulting from agricultural activities, emerged as a surprising culprit.

Ammonium nitrate and memory

“No matter how we examined it, alone or in combination with other pollutants, the most robust finding was that particulate ammonium nitrate was associated with learning and memory impairments,” Herting said. “This suggests that PM2.5 is not one thing overall, but it is a combined effect of what you are exposed to in terms of cognitive functions.”

This discovery highlights the need to reduce the total amount of PM2.5, as well as understand its composition and the effects of individual components.

Protecting children from air pollution

The results obtained are of great importance for health policy. Given the different components of PM2.5, general regulations may not be as effective as policies targeting specific pollutants such as ammonium nitrate.

Policymakers may consider tightening emissions controls for agricultural practices and industries known for high ammonia emissions.

Additionally, implementing educational programs to increase public awareness of the sources and risks associated with particulate matter may enable communities to support and adapt to these regulatory changes.

These informed approaches can lead to better air quality standards and, as a result, better health outcomes.

Research on air pollution and memory

The study opens new avenues to investigate the molecular mechanisms by which ammonium nitrate affects cognitive function.

Future studies could examine the biological pathways of this compound’s effects on air pollution and identify its interactions with memory and the brain as a whole. Ongoing research initiatives may help uncover how lifelong exposure to different components of PM2.5 contributes to cognitive decline in old age.

Additionally, examining geographic and seasonal variations in particulate matter composition can provide insight into regional sensitivity and help tailor interventions more effectively.

Mental health and social well-being

These scientific efforts will be critical to developing policies that effectively protect mental health and social well-being in an era of rapidly changing environmental dynamics.

So what’s next for these researchers? They aim to investigate how these mixtures and air pollution sources may be related to individual differences in memory and brain phenotypes during child and adolescent development.

This research is important for the health of our children and the future of our planet. The findings could lead to changes in air quality and public health policy. The study was published in the journal Environmental Health Perspectives.