Air Pollution's Role in Degenerative Brain Diseases

Photo by Maciek Jasik
Photo by Maciek Jasik

The air we breathe is no longer safe. It is it filled with millions of tiny particles of toxic pollution about 36 times smaller than a grain of sand that may cause or accelerate degenerative brain diseases such as Alzheimer’s and Parkinson’s. Particle pollution’s role in lung disease is well known and backed by years of scientific research; but, recent research correlating pollution and brain trauma has resulted in compelling evidence of its negative role on the brain, despite the research being in its preliminary stages.

Particle pollution contains toxic combinations of sulfate, nitrate and ammonium ions, hydrocarbons and heavy metals – all that reek havoc on the brain’s immune system. But only the fine and ultra-fine particles can reach the brain as natural defenses of sneezing, coughing or running noses eject larger particles. The remaining particles can embed themselves in the lungs to foster infection and cancer or may infiltrate the bloodstream and create dangerous byproducts that can travel throughout the body.

The particles can take a more dangerous lesser know path: they can travel through the olfactory nerves directly to brain. Once there their toxic metals or compounds corrupt the microglia, which are the brain’s special immune cells. The particle pollution causes chronic inflammation which leaves microglia unable to remove waste from the brain or to overproduce chemicals meant to kill unwanted bacteria. Chronic inflammation puts the immune system on over-drive, which has harmful long-term effects and consistently is associated with neurological degeneration. Doctors even use early breakdowns in the olfactory system – through which all of these harmful processes occur – as an indicator of Alzheimer’s and Parkinson’s, further reinforcing the correlation of pollution to degenerative brain diseases.

This information is unsettling as pollution levels rise every year. About 15% of Americans are exposed for extended periods of time to levels of particle pollution about the Environmental Protection Agency standards with another 14% exposed to similar levels on bad air days. This air pollution in the United States affects mostly those who live in undesirable areas such as next to high traffic roads and overcrowded urban areas which happens to be the poor, the elderly and people of color which means the people who can lease afford medical costs, breathe in the most unhealthy air.

Even worse, some cities in China and India face air pollution levels 3-6 times higher than World Health Organization standards. Research from the environmental journal Health and Technology estimates that cleaning up the world’s air could save about 2 million deaths globally. But so many people are already reaping the negative effects of pollution on our brains. 50 million people worldwide are living with Alzheimer’s or Parkinson’s with 6 million of those in the United States. Right now the United States is about to experience the highest number of degenerative brain diseases as the Baby Boomers reach the age where these diseases emerge and since they were born before the Clean Air Act in 1970, their generation has been exposed to the most air pollution than any generation before or after them.

Research is still unclear on whether particle pollution sparks degenerative diseases or accelerates them; however, the research is clear that there is a relationship – one strong enough to be the most potential cause of brain disease.