A growing body of medical research has established a direct link between Alzheimer’s disease, other dementia types and air pollution. Poor quality air seems certain to make these conditions worse.
That’s the conclusion of two researchers associated with Hong Kong Baptist University. They specialize in environmental factors as they affect the neurophysiology of the brain.
Professors Pengfei Fu and Ken Kim Lan Yung conducted a meta-analysis of nine major studies from previous years leading up to March 2020. They found that individuals diagnosed with Alzheimer’s disease and other dementia experienced a worsening of their condition if they lived in locations where the concentration of particulates in the atmosphere is consistently higher.
One of the studies included in the meta-analysis was completed at the University of Southern California (USC) in 2017. It looked at both animal and human data to show that the brain’s aging process is accelerated by air pollution.
The USC study focused on older women living in locations with high levels of particulate matter (PM 2.5) created by automobiles and power plants. They compared their rates of memory loss and brain shrinkage to those of women living in areas where the air is cleaner. The women in the polluted locations show statistically significant poorer rates of performance in brain-related processes, such as memory and cognitive-reasoning functions.
Air Pollution Not a Cause But Contributor
It’s important to note that the most decisive cause of Alzheimer’s or other forms of dementia is a genetic predisposition for these conditions. Scientists say genetic factors account for about 70 percent of the risk. The remaining 30 percent is a combination of factors, such as old age, lifestyle choices and environmental factors.
Even so, pollution can certainly be considered a “substantial elevator” of risk—enough to conclude that cities and countries well-known for frequent and heavy air pollution are exacerbating a known problem. That’s because the median age of the world population is steadily increasing, and dementia is largely a disease of old age.
Harmful Air Pollutants
Pollution is largely the result of human activities. Sulfur and nitrogen oxides and other pollutants are produced by the combustion of fossil fuels, industrial processes and vehicle emissions. This is released into the atmosphere or directly to the ground. While these compounds have been present throughout the history of man, only in recent years has their concentration on land and in water increased.
According to the World Health Organization, pollution is one of the world’s biggest environmental risks. It is estimated that 91 percent of the world’s population lives in places where outdoor air quality fails to meet WHO guidelines.
There are many pollutants in outdoor air. Some that cause a greater risk for Alzheimer’s and other dementia include the following:
This is formed when nitrogen oxides and volatile organic compounds released by combustion (such as vehicle engines and industrial processes) “mix with sunlight during the summer to create ozone.”
This harmful substance is found in the air due to the burning of fossil fuels. While lead has been banned from paint, its use in gasoline continues to contaminate the environment.
PM10 is a mixture of solid particles and liquid droplets that can be found in the air. Particles from PM10 to PM2.5 “are small enough to enter the lungs, where they can lead to lung and heart diseases and even premature death.”
This gas is a “toxic gas” produced by cars, trucks, engines and power plants. It “formulates in the atmosphere, eventually making its way down to the ground, where it enters the lungs and causes symptoms such as coughing, asthma and shortness of breath.”
Pollution of indoor and outdoor environments is one of the reasons for the increased prevalence rates of Alzheimer’s disease in densely populated areas. However, there are other, non-environmental factors associated with Alzheimer’s as well, the first one being age—being older than 60 is a risk factor. The following are some other non-environmental risk factors:
- Down syndrome
- Alcohol Abuse
Reducing the Risk
Just because you are not exposed to hazardous air pollutants every day does not mean you shouldn’t take precautions. Even if it is not a major concern for your area, there are certain things you can do to reduce your exposure to it.
Air pollution is a global issue and affects everyone in some way. Even if the air in your geographic location is relatively clean, you should monitor the AQI (Air Quality Index) daily to see if any dangerous pollutants are emitted from nearby industries.
Using public transportation if possible and exercising outdoors are also great ways to combat this pollution. It would help if you also considered buying a simple and inexpensive home air filtration system for your home, car or RV to help keep pollutants from entering your indoor space.
There has been a substantial rise in rates of Alzheimer’s disease. Most of this rise is attributed to air pollution. However, several factors contribute to this increase as well. We must consider these numbers and do what we can to reduce air pollutants that can affect our health.