Where Does Dust Come From? (6 Indoor Sources)

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Growing up I always noticed there was an endless supply of dust.  One of my weekly chores was to dust and vacuum but the dust kept accumulating.  Where was all this dust coming from?

Have you ever sat down on a couch and watched dust disperse into the air?  Maybe you’ve also seen dust glistening in the morning sunlight, or accumulating on the floor in the corners of your house and wondered “Where does dust come from”.  The fact is, dust is everywhere.

If you’re curious about dust, don’t worry, you’re not alone.  I grew up with a lot of dust and I bet you did as well.

Once you understand where dust comes from you’ll be able to reduce the amount of dust in your home.  The problem starts with “us”.

This article will outline the origins of dust, why it is grey colored, and what dust looks like under a microscope.  After learning about dust, we’ll examine ways to reduce it in your home.

Where Does Dust Come From (6 Indoor Sources)

Dust can be made up of many things.  Outdoor dust is usually made up of soil, organic matter like leaves and grass, pollen, and mold.

But there shouldn’t be dust in our homes because they are protected from the outside elements, right?  There is no way all those things can cause the dust in our homes.

Below is a list of contributors to indoor dust and some of them might surprise you!

#1 Human Skin

The number 1 source of indoor dust is human skin.  Gross right?  Human skin sheds constantly as our bodies produce beautiful new layers underneath.

Most of us don’t realize we’re shedding skin unless we have dandruff, eczema, or dry skin.  However, even healthy skin is constantly falling off our body and being replaced by new skin cells.

Although it’s unpleasant to think about, most of the dust you see in the corners of the floor, or on your bookshelf is actually your skin (or your family’s depending on who you live with).

#2 Human Hairwhere does dust come from - hair

Human hair is another major source of dust.  This culprit is more understandable because we witness our hair falling out all the time.

Whether it’s combing our hair or bathing in the shower, we always see a few hairs that have fallen off our head.

Human hair falls on couches and floors and accumulates next to the other dust sources on our list.  Because hair is larger in size, it’s much easier to clean up!

#3 Pet Skin/Hair

In recent decades, pets have been brought indoors to live with their human friends.  Similar to humans, pets also shed skin cells and shed hair.  Pet skin cells are harder to see (just like humans) but they contribute to a lot of dust.

Pet dust is called dander and can be an allergic trigger.

If you’ve ever been in a house with a dog or cat you’ve likely seen pet hair everywhere.  The shed hair can get on your clothes and really make a mess.

Pet hair usually ends up on the floor where it mixes with the other dust on our list.

#4 Dust mites

Have you heard of dust mites?  Dust mites are interesting creatures that are both consumers of dust and producers of dust.

Dust mites are microscopic and they can’t be seen unless under a microscope.  Believe it or not, they live in the majority of homes.

Don’t worry they don’t bite and don’t bother people (…unless you have allergies).  True to their name, dust mites feed on dust.  If you live in a dust house chances are you have dust mites quietly eating dust on your floors, beds, and carpets.

#5 Dust mite feces

Dust mites also contribute to dust with their fecal matter and their dead populations.  They have short lifespans but when they are alive they reproduce quickly and deposit plenty of fecal matter.

The fecal matter is actually what is highly allergic for humans (there’s a protein found in alive, dead, and fecal matter that can irritate skin, sinuses, and the respiratory system).

#6 Pollen/dirt

Pollen and dirt make up the last source of indoor dust.  Air enters our homes anytime we open a door or window.  With that air comes plenty of microscopic particulates.  They float around our homes and eventually settle on the floor, adding to dust in our home.

Pollen and dirt also enter our homes on pets and humans who have been outside.  Most people believe that pollen and dirt make up the highest percentage of dust in our homes but it’s not likely.

Although there are a number of contributors to indoor dust, the main components are shed human skin, pet dander, and dust mites and their feces.  As you’ve just discovered, dust is disgusting…maybe if people knew more about indoor dust, they’d be more active with cleaning.

The video below shares some good information on the ever-annoying dust.

Why Is Dust Grey

Have you ever wondered why dust is grey in color?  If so, you’re not alone.  There are various types of dust that come from outside and inside our homes.  However, indoor dust always seems to be grey.  Why is this?

Interestingly, grey is the color of our dead skin.  When our skin is alive, it displays various shades of color, from brown, olive, black, and white depending on our race.  However, our largest organ, our skin, is always shedding and producing new skin to protect our body.

This occurs 24 hours a day.  The dead skin falls off our body in the shower or while we’re sleeping or walking, and once we lose skin it becomes a grey dust that falls onto our floors and waits to be swept up.

When hair begins to break down it becomes a grey color too (although hair takes much longer to break down than skin). If you have pets inside your home, they also contribute to the grey dust you find on the floors.  While it might be unsettling to think about, shedding skin is a natural process.

Dust Under A Microscope

Warning, this might be disturbing after learning that dust is everywhere in your home including your bed.  This is a video of dust mites frolicking in “dust”.

Remember, we can’t see them with our normal eyesight, but they exist, going about their business on your floors and in your carpets and beds.

Most people aren’t bothered by dust mites so don’t be alarmed.

Reasons To Understand Where Dust Comes From: Health Problems

Little did I know, and as I found out later, dust was causing me harm in more ways than I imagined.  Dust affected my breathing at night and when I exercised indoors during the day.  Dust made my eyes, ears, and mouth itch.  It also gave me rashes when my skin was against it.  My nose was constantly congested too.

It may seem harmless, but indoor dust can cause a number of health issues.  We primarily see dust on the floor or on bookshelves.  It’s common sense that if there’s dust on the floor, there’s definitely dust in the air.

Once stirred up into the air dust can remain suspended in the air for hours.  When inhaled, dust can enter the sinuses and lungs.  If indoor dust is at a high concentration, the tiny particulates can irritate airways and cause irritation to eyes, ears, and nose; even for people who aren’t allergic.

For allergic individuals, the effects of dust can be worse.  In the U.S. as many as 10 percent of the population and 90 percent of people with asthma are sensitive to dust mites.  In other words, dust mites are a big problem and allergies in the U.S. are increasing at a high rate.

Dust is a reason for concern because unlike seasonal pollen or mold allergies, dust is a constant, year-round allergen.  It can affect people so badly it can even cause depression!  Dust allergies, including dust mites, animal dander, and pollen can cause a wide array of symptoms:

  • Asthma

  • Wheezing/Sneezing

  • Rhinitis

  • Conjunctivitis

  • Itchy eyes, nose, ears

  • Persistent cough

  • Post nasal drip

  • Eczema and itchy skin

  • Fatigue and foggy mind

Wash To Reduce Dust

Lastly, it’s important to mention washing. Washing is extremely important to get rid of dust mites and their feces.  Using an anti-allergen laundry detergent is a smart move for you and your family.  It will help reduce dust mite populations by killing mature mites and their larvae.

Simply washing won’t kill dust mites so we recommend adding essential oils to your detergent or purchasing allergen detergent with the essential oils already added.  If you use dust mite covers on your bed you won’t have to wash as frequently!


Indoor dust comes from a variety of sources but primarily is from dead human skin.  With regular cleaning, most people won’t be bothered by dust, however there is a growing trend towards allergies, including dust mites which eat our dead skin.   Allergies can include rashes, rhinitis, post-nasal drip, conjunctivitis among others. Regular cleaning can reduce allergen exposure and thereby prevent allergic symptoms such as puffy eyes, congested nose, rashes, and asthma.

Dust is fairly easy to pick out.  It is grey in color and is found in the corners of our homes where dust mites recycle the material.  Although we can’t see dust mites with the naked eye, they exist in our homes alongside us.

If you’re curious about reducing dust inside your home, there are a number of things you can do.  When cleaning, be sure to use a HEPA vacuum.  The term HEPA is important to get the smallest of dust particles.  Another simple action to take is to invest in an allergy HVAC filter.

Using an allergy HVAC filter when running the air conditioning and heater will help suck up and trap dust in the air.  It will also improve the air quality inside your home which is very important for children with allergies.  An air purifier in the bedroom can add to the improved air quality and clean air multiple times a day (I use one in my bedroom and it works!).

Dust mite proof covers (don’t forget to wash regularly) are probably the most hygienic thing you can do in the bedroom.  Dust mite bed covers will protect your skin from contact with dust mites and ensure you experience better quality sleep without the morning congestion.

We hope this article answered your question on “where does dust come from”.  Visit us at Dust Mite Solutions for more tips, reviews, and products.

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