And the effects are not just impacting our pulmonary or cardiovascular health – we now know that our brain health is equally compromised.
Mounting evidence links a variety of neurological problems to dirty air that is particularly exacerbated in urban cities throughout the world. Recent findings have shown hallmarks signs of Alzheimer’s disease in the brains of children living in Mexico City.1 Older women in the U.S. who live in highly polluted areas have a nearly doubled risk of dementia.1 Rates of autism are also notably higher in more polluted geographic locales and studies have shown that prenatal exposure to air pollution increases the risk of developing the disorder.2
Learn more about how pollutants enter the brain:
The global impact of air pollution was the focus of a paper in The Lancet Neurology3 that cited among other findings “that air pollution might cause 30% of all strokes, and thus might be one of the leading contributors of the global stroke burden” as was highlighted in an analysis of stroke and risk factors from the Global Burden of Disease Study 2013. The mechanism of action is most likely a direct effect of particulate matter—a mixture of solid particles and liquid droplets found in the air and in gases such as ozone and nitrogen dioxide—on the vascular system, causing oxidative stress and inflammation.
Even if the risks of neurological effects for individuals that is attributable to air pollutants might be small to modest, the overall attributable risk could be considerably higher, given that a large proportion of the population is exposed to air pollutants. Also noted by The Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study reported that “air pollution alone was responsible for 6·7 million deaths globally in 2016.” The Study also cited that 92 percent of all deaths linked to air pollution were in lower to middle income countries – yet another example of the disproportionate burden faced by individuals with less access to regular or even any healthcare and related education about these issues.
A mix of released gases and fine particles from burning trees and plants, structures, and other materials, wildfire smoke is now estimated to bear 40 percent of the responsibility for particulate matter pollution. But it’s hardly the sole contributor to dirty air. Vehicle exhaust fumes, burning of fossil fuels, chemicals used in agriculture and other settings, construction with lack of proper land reclamation, industrial emissions and so many other factors put virtually all of us at some risk of breathing dirty air. Globally, more than 90 percent of people breathe air that fails to meet WHO standards* and that includes an estimated four in ten people in the United States alone whose health may suffer from the negative effects.
In addition to advocating for cleaner industrial and commercial manufacturing and other standards, there are a few things we can all do to try and help reduce air pollutants:
Experts warn that forests lost to wildfires may never fully regenerate at least in the near future and especially not at lower elevations. And without the ability to capture carbon through trees, climate change is only going to intensify. We are living in literally toxic times and it is a problem we must solve together. It’s about more than making a difference to our brain or overall health – it’s truly about the health of our planet today and tomorrow.
In hope and healing,
Dr. Suzanne Gazda
References and additional reading:
1 Peeples, L. News Feature: How air pollution threatens brain health. Proceedings of the National Academy of Sciences. Jun 2020, 117 (25) 13856-13860;
DOI: 10.1073/pnas.2008940117. https://www.pnas.org/content/117/25/13856
2 Pagalan L, Bickford C, Weikum W, et al. Association of Prenatal Exposure to Air Pollution With Autism Spectrum Disorder. JAMA Pediatr. 2019;173(1):86–92. doi:10.1001/jamapediatrics.2018.3101
3 Air pollution and brain health: an emerging issue. The Lancet Neurology. Vol. 17, issue 2, P103, February 01, 2018. https://doi.org/10.1016/S1474-4422(17)30462-3
* World Health Organization (WHO) on air pollution and particulate matter. https://www.who.int/news-room/fact-sheets/detail/ambient-(outdoor)-air-quality-and-health
Real-time Air Quality Index: Main causes of air pollution.
Colorado Public Radio News
Dr. Suzanne Gazada, Integrative Neurology