Pollution impact: How ammonium nitrate harms young minds

New research by scientists at the University of Southern California has shown that certain forms of air pollution, including those related to agriculture, have a notably negative effect on children's cognitive functions and increase the risk of Alzheimer's disease and dementia in adults.

The latest findings, published in the journal "Environmental Health Perspectives," highlight the harmful effects of ammonium nitrate—a substance primarily linked to agriculture and livestock farming. Scientists analyzed data from 8,500 children aged nine and ten to study the impact of fine particulate matter PM2.5 on brain development.

These tiny particles, which are a mix of dust, soot, organic compounds, and metals, can infiltrate the lungs and enter the bloodstream and brain, bypassing the blood-brain barrier. Their presence in children's bodies is associated with negative outcomes.

While the largest source of PM2.5 is the combustion of fossil fuels, especially in urban areas, significant contributions also come from wildfires, sea aerosols, chemical reactions, and agricultural activities. Researchers used advanced statistical methods to examine 15 chemical components of PM2.5 and their sources. They found that specific types of air pollution can affect the brain to varying degrees, with ammonium nitrate being the main factor negatively impacting cognitive functions.

“Whether we studied it separately or in conjunction with other pollutants, it was always linked to poorer academic performance and worse memory,” said the lead author of the publication, Dr. Megan Herting. She suggests that while the overall harmfulness of PM2.5 is significant, some compounds within this mixture pose a greater threat to health than others.

The authors emphasized the need for more detailed analyses of the sources of particulate matter and their chemical components. Understanding these nuances is crucial for establishing air quality regulations and understanding long-term neurocognitive effects.

In conclusion, the researchers highlighted that PM2.5 can cause neurocognitive effects that persist throughout life. They believe this knowledge should prompt a reevaluation of air quality regulations to protect future generations from the negative impacts of pollution.

Although research indicates that ammonium nitrate, used in agriculture as a fertilizer, is particularly harmful to children's brains, the overall contribution of agriculture to PM2.5 emissions is not large. According to the Ministry of Agriculture, a report from KOBiZE in 2020 estimated that PM2.5 emissions from agriculture in 2018 accounted for 2.4% of the total emissions.

Prof. Dr. hab. Eugeniusz R. Grela from the Department of Bromatology and Nutrition Physiology at the University of Life Sciences in Lublin discussed greenhouse gas emissions from agriculture. He confirmed that agriculture emits significant amounts of these substances, but the issue is complex.

"It is worth remembering that methane may differ in terms of its rate of decomposition in the environment. Methane from livestock production has a much shorter duration, lasting about ten years, compared to fossil methane, which can take up to 100 years to decompose," noted Prof. Grela.