A recent study published in PNAS disclosed that harmful particles carried by air pollution can enter the brain and have been found in the cerebrospinal fluid of persons who have been diagnosed with brain disorders.

Researchers from a Chinese hospital investigated the blood and cerebrospinal fluid of 25 patients with diverse mental illnesses. They discovered a range of harmful small particles in the blood and cerebrospinal fluid in 32% of the patients. Additionally, samples from 26 healthy individuals were also tested and only 1 among them had any particle matter. They found some substances specifically found in air pollution, such as calcium-based particles like calcite and aragonite, minerals that are frequently used in building materials, abrasives, soil treatment, pigments, and as a pharmaceutical additive.

The mice used in the study were exposed to fine airborne particles, and the findings showed that up to eight times as many of these particles may enter the bloodstream from the lungs and travel to the brain as opposed to entering directly through the nose, demonstrating the harmful effects of air pollution on the brain. Thus the study on mice revealed that particles are likely to stay in the brain for a longer period compared to other organs.

The study also revealed that people who breathed fresh and clean air did suffer from Alzheimer′s disease, but 40% of people who had lived in polluted areas had the disease. Thus it was evident that air pollution may contribute to several neurological conditions, such as dementia, Alzheimers disease, and brain ageing, and may raise the risk of stroke, depression,  Attention-Deficit/Hyperactivity Disorder (ADHD), schizophrenia, and other mental health conditions. (Medical News Today, June 27, 2022)