Wildfires and farming activities are important sources of air pollution and factors linked to an increased risk and cases of dementia. The fumes from wildfires and farming pose a particular toxic threat to cognitive health, according to the University of Michigan.
This is based on data that shows how exposure to air pollution makes the brain more susceptible to dementia. This is due to harmful emissions released at high concentrations.
In the U.S., as well as other parts of the world, wildfire smoke is becoming a more widespread stressor with many cities experiencing 30-plus days each year impacted by smoke. Given the extremely high levels of exposure to the public, there are a number of health associated risks.
The biggest risk factor is from the swirling mix of microscopic toxins found in air pollution, specifically fine particulate matter or PM2.5. Such small particles can enter the brain through the nose directly or cross the blood-brain barrier in other ways.
According to Sara Adar, environmental epidemiology researcher at the university’s School of Public Health: “We saw in our research that all airborne particles increased the risk of dementia but those generated by agricultural settings and wildfires seemed to be especially toxic for the brain.”
The research suggests that particulate matter air pollution from agriculture and wildfires might be more neurotoxic compared with other sources. More research is needed to confirm these effects.
The research is based on a study into the development of dementia among nearly 30,000 adults from across the U.S. over an 18-year period. The data comes from the Health and Retirement Study, a U.S/-wide collection of cohorts of older adults who have been followed since 1992.
The researchers deployed a prediction model that includes information about the chemical transformations and dispersion of pollution from different sources to estimate the levels of source-specific particulate matter air pollution at participants’ residential addresses.
The connection between agriculture and wildfires in being associated with greater risks of dementia could not be explained by other factors such as individual, neighbourhood, socioeconomic status, occupation, or hometown or region of the country.
Remediation is, however, possible, as Adar adds: “Our findings indicate that lowering levels of particulate matter air pollution, even in a relatively clean country like the United States, may reduce the number of people developing dementia in late life.”
Hence it may be possible to design interventions for specific sources as a more effective way to decrease the burden of dementia.
The research has been published in the Journal of the American Medical Association’s Internal Medicine, titled “Comparison of Particulate Air Pollution From Different Emission Sources and Incident Dementia in the U.S.”