PM2.5, The Invisible Threat That Kills 4.2 Million People A Year

What are we taking into our bodies when we breathe? While the composition of air changes constantly,  it’s mostly made up of varying degrees of nitrogen, oxygen, water, carbon dioxide, and ozone. 

But, that’s not all you’re breathing in. No matter where in the world you live, every day you are taking particulate matter (PM) into your body. What exactly is PM and how dangerous are they?

What is Particulate Matter?

Particulate matter are a mixture of solid particles and liquid droplets found in the air. Some particles, such as dust, dirt, soot, or smoke, are large or dark enough to be seen with the naked eye. Others are so small they can only be detected using an electron microscope. 

PM are usually classified as particulate matter, fine particles, or ultrafine particles. 

PM 10 (particulate matter) are inhalable particles, with diameters that are generally 10 micrometers and smaller. 

PM2.5, also known as fine particles, are those that are smaller than 2.5 micrometers in diameter. PM2.5 are about 30 times smaller than a human hair. 

Ultrafine Particles (UFP) are particulate matter that are less than .1 microns in diameter. 

Exposure to any particulate matter can cause health issues, but fine and ultrafine particles are the most dangerous. 

What is Particulate Matter composed of?

It depends on where you live. Each location has its own mix of contributors depending on geography and human activity. But, no matter where you’re located, air pollutants come from two sources: nature and human activity

  • Natural sources include: windblown dust, dirt and sand, volcanic smoke, and burning materials.
  • Man-Made sources include: various forms of combustion, such as from gas-powered transportation, industrial businesses, biomass burning (the burning of plant matter or coal for heating, cooking, and energy), and farming.

How dangerous are Particulate Matter?

One recent study called PM 2.5 “the largest environmental risk factor worldwide,” responsible for many more deaths than alcohol use, physical inactivity or high sodium intake. In fact, 4.2 million people die every year from breathing in large amounts of fine and ultrafine particulate matter. 

Another study showed that air pollution reduces global life expectancy by more than a year.

But, why? What is it that makes these invisible particles so deadly?

The answer lies in their size. Because PM2.5 and ultrafine particle matter are so small, they are easily inhaled and are able to penetrate deep into your respiratory system. 

Short-term issues from PM exposure include eye, nose, and throat irritation, coughing, sneezing, and shortness of breath. Long term exposure to PM2.5 can cause permanent respiratory problems such as asthma, chronic bronchitis, and heart disease. PM2.5 particles also elevate the likelihood of premature birth and infant mortality.

What makes the danger of particulate matter even more difficult to assess is that it’s rarely the direct cause of death. Rather, air pollution is the world’s 4th leading contributing cause of early death, accounting for:

  • 29% of all deaths and disease from lung cancer
  • 17% of all deaths and disease from acute lower respiratory infection
  • 24% of all deaths from stroke
  • 25% of all deaths and disease from coronary heart disease
  • 43% of all deaths and disease from chronic obstructive pulmonary disease

Who is most vulnerable to the ill effects of Particulate Matter?

Older adults with chronic heart or lung disease, people with asthma or other respiratory illness, and children are the groups most likely to experience adverse health effects from exposure to particulate matter. 

Children and infants are particularly susceptible because they inhale more air per pound of body weight than do adults – they breathe faster, spend more time outdoors and have smaller body sizes. 

In fact, California’s Children’s Health Study found that children living in communities with high levels of PM2.5 had slower lung growth and smaller lungs at age 18 compared to children who lived in communities with low PM2.5 levels.

Can we avoid Particulate Matter by staying indoors?

Unfortunately, indoor air is usually two to five times more polluted than outdoor air. That’s because human activity generates a whole lot of Particulate Matter. Every time you cook, burn wood, candles or incense you are releasing large amounts of particulate matter into the air. Particles also can form indoors from complex reactions of gases emitted from things like household cleaning products and air fresheners.

Human activity and products, combined with the lack of ventilation, produces and retains large concentrations of particulate matter. 

But particular matter is not just generated indoors. No matter how tightly sealed your home is, particles can still enter indoor spaces through doors, windows, and “leakiness” in building structures.

How can we stay safe from Particulate Matter?

Unfortunately, there is no way to completely avoid breathing in particulate matter.  But you can lessen your exposure.

To minimize your exposure to PM outdoors:

  • Check your air quality before going out.
  • Go outside in the mornings, when ozone levels are lower.
  • Walk away from traffic.
  • Stay near trees or shorelines.

To minimize your exposure to PM indoors:

  • Ensure that gas stoves are well ventilated.
  • Reduce the use of harsh cleaners and scented products.
  • Keep windows and doors open as much as possible.
  • Purchase a high-quality air purifier with a True HEPA filter.

Why do HEPA filters make such a big difference?

Although the standard for HEPA filters is that they need to be able to filter out 99.95% or more of all particles which are 0.3 microns in diameter, they are actually capable of filtering out particles of almost any size. A True HEPA filter can trap dust, smoke, pet allergens, and, most importantly, PM2.5.

That means that, if you have an air purifier with a True HEPA filter, you can be assured that particulate matter of all sizes will be filtered out of your home, improving your health and increasing your life expectancy.

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