If you read or watch any news about pollution, you have probably seen or heard the phrase “PM 2.5.” But what is PM2.5? And how does it impact human health?
In today’s post, I’m going to feature some more environmental health-focused writing. I do a fair share of environmental health writing, but don’t do it very often on this platform. But I want to give it a whirl! So today, right here right now on my blog, we’re going to take a look at what PM stands for, what it is exactly, and why it’s relevant to human health. Get excited!
First, let’s start off by defining “PM,” which stands for Particulate Matter. Particulate matter is an air pollution term for a mixture of extremely small solid particles and liquid droplets found in the air, made up of a variety of compounds including acids (such as nitrates and sulfates), metals, organic chemicals, dust, and soil.
Where does PM come from?
PM and PM precursors (which later form PM) come from a variety of human-caused sources, including motor vehicles, power plants, factories, dry cleaners, gas stations. There are also a couple natural sources of PM, including PM emitted from volcanoes and wildfires.
The size of PM is directly linked to the potential for PM to cause health impacts. Generally speaking, the smaller the particle, the deeper it can penetrate into your lungs, and thus, the more likely it is to do damage. Particles smaller than 10 micrometers in diameter are focused upon, due to their potential to be inhaled and cause detrimental health impacts.
PM 2.5 versus PM 10:
‘PM 10’ refers to dust particles 2.5-10 micrometers in diameter. These particles are smaller than the width of a human hair and can be inhaled.
Particles less than 2.5 micrometers in diameter are known as “PM 2.5,” and are too small to see with the naked eye. PM 2.5 can penetrate deeper into the lungs than PM 10, and thus is more likely to get into the blood supply and be carried throughout the body. Likely due to their high potential to cause negative health impacts, they are the most talked about in popular media.
So how does PM 2.5 impact human health?
PM can impact health in a variety of ways. For starters, PM impacts the lungs, and may cause coughing, shortness of breath, tightness of the chest and difficulty breathing. It can also exacerbate symptoms of asthma. Long-term exposure may lead to reduced lung function development, respiratory disease, and even premature death.
PM also affects the cardiovascular system. In fact, air pollution is now being considered by many to be an independent risk factor for cardiovascular disease. How? Inhaled particles can make their way into the bloodstream and can cause oxidative stress and induce systemic inflammation in peripheral circulation, causing irregular heartbeat, stroke, aggravation of existing heart conditions, and heart attacks, . As cardiovascular disease is the number one killer in America, this is a major cause for concern.
PM has also been documented to be an eye irritant, which makes sense, because no body likes dust in their eyes.
Who is Most At Risk?
Children are particularily susceptible to PM exposure, as they have a more frequent rate of respiration than do adults. Their lungs are also still developing, further increasing risk. Elderly adults with lung diseases (diagnosed or undiagnosed) are also at high risk. People of any age who suffer from asthma or heart conditions may also feel their symptoms exacerbated by PM exposure. Those who work or workout outside are also highly susceptible.
And What About Pets?
Of course, because I’m me, I had to look into if PM 2.5 has been documented to impact our furry friends. Scientists are just starting to explore this topic, but existing studies suggests that elevated PM 2.5 increases the risk of respiratory disease in cats and dogs. There isn’t much data yet, but I would venture to guess PM may also impact their cardiovascular systems, as it does to humans.
How Can I Reduce My Exposure to PM 2.5?
The level of PM you are exposed to is directly affected by your living and working environment. In some densely-populated cities with poor environmental regulations, PM is very high; in other areas, PM is much lower. Living near certain emission sources, includinng power plants and airports, also increasing risks of exposure.
Even in areas that typically have lower levels of PM 2.5, certain events or activities may increase PM 2.5. Checking the local AQI (air quality index) is a wise way to monitor the levels of PM you are exposed to.
Obviously, not everyone can control where they live and work. And unfortunately, power plants and other large sources of pollution exposure are often placed in low-resource areas.
Whether you live by a source of PM, are in the middle of a PM-heavy city, or are experiencing wildfire smoke, If the AQI is high, try to stay indoors as much as possible. Air conditioning and/or allergen filters may help keep your air cleaner. And avoid exercising outdoors – the rapid rate of respiration will only increase the amount of PM you inhale.
Oh, and if you’re looking to make a lasting difference, advocate for policies that support regulating pollution, and support politicians who champion these issues with your votes.