New research suggests that high levels of air pollution may increase the risk of Alzheimer’s disease and other degenerative conditions, finding that toxic particles may penetrate the brain.
In a study published this week in the journal Proceedings of the National Academy of Sciences of the United States of America, researchers indicate that participants living in high pollution areas have high levels of magnetite in their brains, which has been linked to Alzheimer’s disease.
Magnetite is a magnetic iron oxide compound produced from industrial air pollution that is toxic to humans. It can have serious effects on the brain due to its surface charge and strong magnetic behavior. Magnetite is often found in polluted urban areas.
High levels of magnetite were found in the brain tissue of 37 people who lived in two polluted urban areas, Mexico City and Manchester, England. The magnetic compound was found to be coupled with similar metals.
Researchers say this is cause for concern since magnetite is ubiquitous and abundant in airborne particulate matter pollution. It is considered toxic to the brain and has been linked to the production of damaging reactive oxygen species (ROS). Increased ROS production has been causally linked to Alzheimer’s and other neurodegenerative diseases.
Magnetite pollutant particles which are less than 200 nm in diameter can be inhaled and enter the brain tissue through the olfactory bulb nerve, the area that connects the nose to the brain and allows humans to smell.
Magnetite is formed from any fuel burning activity, including car exhausts, industrial power plants and other combustion sources, making it nearly impossible to escape in the environment.
Air Pollution Health Concerns
Air pollution contributes to millions of premature deaths each year, health experts say. Other studies have linked air pollution to harmful health effects, such as increased risk of stillbirth in pregnant women as well as increased risk of heart disease, and a heightened risk of stroke.
Pollution, even at low levels can harm humans. Nearly 6,500 people die early each year in the US due to air pollution, nearly 40,000 in the UK, and millions worldwide including highly pollution areas such as China and India.
A report published in June indicated more than 4.5 million people will die from air pollution by 2040, unless drastic measures are taken to improve air quality. Energy use and production from unregulated, poorly regulate, or inefficient fuel combustion are the most significant man-made sources of air pollution, creating more than 85% of particulate matter.