Impacts of Air Pollution on Human Health
You’re walking along a busy street, minding your own business, when suddenly you get a whiff of something very unpleasant. Mercifully, a breeze blows and the scent is mostly gone, but it still lingers. What is that? That is Particulate Matter (PM) 2.5 (soot), nitrogen oxide, volatile organic compounds (VOCs), and sulfur dioxide! These are released into the air as a result of burning fossil fuels such as gasoline and diesel. They’re more than a nuisance that makes your nose scrunch in an undignified expression. Let’s explore, shall we?
Lucky for us, a literature review published in February 2020 will help guide our journey through this complicated topic.
Air pollution caused by human activities accounts for 9 million premature deaths annually. PM 2.5 is a very fine particle. So fine, that when you breathe it into your lungs, it gets absorbed into the bloodstream and increases inflammation throughout the body. Air pollution affects any disease worsened by increased levels of inflammation.
For example:
COPD (Chronic Obstructive Pulmonary Disease) and asthma
These are both chronic respiratory diseases driven by inflammation. They are chronic because once you have them, you’re stuck with them for life. Chronic conditions can have acute exacerbations. This is when a person experiences symptoms despite having previously had the condition well-managed. This is what rescue inhalers are for, and they can help. When they don’t, I’ll see you in the ER. The image below from the Lung Association of Canada is a good illustration of why this is so dangerous.
Heart disease
This is an umbrella term for several conditions, all of which are chronic and driven by inflammation in the body. Again, you can have acute exacerbations, and if your rescue meds don’t work, you’re headed to the ER.
Diabetes
Any inflammatory process can increase blood sugar levels.
Cancer
Any inflammatory process increases cell turnover in the body. This means cells are being replaced more rapidly, and replacing cells involves copying DNA. The more frequently your cells copy their DNA to make new cells, the more likely they are to make mistakes that could lead to cancer in any part of your body. And remember what your health ed teacher told you about smoking being like putting your mouth on a tailpipe and breathing in? (Or was mine just super aggressive?) You may not smoke, but you are still at risk for lung cancer.
Miscarriage and stillbirth
Living near a highway increases the risk of miscarriage and stillbirth due to the increased levels of inflammation in the mother and the ability of PM 2.5 to cross over into the placenta.
Babies and young children are more susceptible to any inflammatory airway process because their airways are proportionally smaller than the rest of their bodies compared to adults. In other words, they have less margin of error when pollution enters their airway, irritates it, and it starts to swell shut from the inflammation.
Over a lifetime of exposures to various airway irritants, the body begins to lose its ability to bounce back. This means that the older you are, the more vulnerable you are to additional exposures and the resulting inflammation.
Fortunately, inflammation tends to be a slow and gradual process, leaving time to intervene in most cases. Even if you live by a highway, there are things you can do to decrease your risk. We’ll get into the details in another post.
