When trying to figure out why black spots are appearing on your sheets, bed bugs could be the culprit -- but there are other potential causes to consider first. Flea droppings, aphids, carpet beetles, and mold can all leave similar dark spots behind on bedding.
Black Spots
Since bed bugs feed on blood, they often excrete this digested blood, and it can show up as a smattering of small dark spots on your sheets as time passes. If you see a cluster of small black spots on your bedding and know you don't have a mold problem, bed bugs could be the culprit.
If you're finding tiny black droppings or black staining, you may have bed bugs. You see blood stains - Bed bugs cause blood staining in areas of infestation, and also in areas where they are feeding.
Since bed bugs like to hide in cracks and crevices, Dr. Pereira says you might have an easier time seeing signs that the nasty critters were there vs. actually having a bed bug sighting. Bed bugs will leave black fecal spots (basically dried, digested blood) around the places they're hiding.
If you see small flakes all over your bed or clothing, you have a home bed bug infestation. The molted skins are a clear reddish-brown with an oval shape.
Bug shells: As bedbugs grow, they shed their outer shells. These shells look like small brown flakes and can often be found near where the bugs are hiding (e.g., in cracks in furniture or in the seams of mattresses).
Clover mites are very tiny as can be seen on this ruler. The mites are very tiny creatures (smaller than a pin head) and may occur in countless numbers. They usually appear first around windows, but later may overrun entire walls of a home. To most people they appear as tiny, moving, black specks.
Moss mites
They are tiny black insects with a round shape and a length of about 1-2mm (0.04-0.08 inches). They are usually found outside in shaded areas of gardens and yards, and you are most likely to see them under plant leaves as well as in the soil or on compost piles.
Springtails, also known as snow fleas, thrive in wet or damp areas, where they gather in large clusters. From far away, they can look like little specks of dirt or particles of pepper in the snow. When I first encountered springtails, I didn't even see them until they were inches from my face!
Rat droppings are usually a shiny dark brown or black colour and they look like small pellets. Each dropping is typically between 12 and 18 millimetres long. Mice droppings however are smaller with pointed ends and are usually brown, black or white.
Since bed bugs only feed on blood, their poop has a consistent color, size, and shape. The color of bed bug poop is generally a very dark rusty brown color that almost appears black in some instances. Since bed bug waste is a byproduct of blood, the consistency tends to be more liquid than solid.
Bedbugs. If you find tiny bugs that look like black sesame seeds in your home, there's a high chance that you're looking at bed bugs.
Black spot mould (also known as Aspergillus Niger) is a common problem in households due to leaks, moisture in the air, and poor ventilation throughout the property. Black mould doesn't just look horrible either. It can cause major damage to your furniture, and have a real impact on your physical health.
You may find yellow or black spots on the surface or inside of the cotton, but this is a natural cottonseed shell.
No matter how hard you work at cleaning, there eventually comes a time when you'll look up and see blacks dots on your ceiling or appearing on the tile in your shower. These black dots are almost always mold or mildew. It's always challenging to keep mold and mildew out of bathrooms and kitchens.
If you're seeing small black specks that look like pepper flakes or dirt, it could be fecal matter from carpet beetles or fleas. Carpet beetles leave behind small yellow-white larvae and shed skins; flea droppings look like small dark specks and may also come with larvae.
In contrast, dust mites can really only be seen under the microscope. House dust mites are about 0.1–0.4 mm long [2], less than one tenth the size of a bed bug, at least. House dust mites are translucent to white in color and have been described as “globular” in shape [3].
The common name "black pepper mite" comes from the unusual appearance of these mites. Bites from bird mites may also be a source of so-called "mysterious bug bites" when they erupt suddenly with no obvious cause.
The scabies rash consists of tiny red spots. Scratching the rash may cause crusty sores to develop. Burrow marks can be found anywhere on the body. They're short (1cm or less), wavy, silver-coloured lines on the skin, with a black dot at one end that can be seen with a magnifying glass.
Use a magnifying glass and a flashlight to inspect the area. Look for black specks (living bedbugs) or pearl white larvae. Peel back the fabric where it is stapled to the bed frame. Check in the crevices and underneath the surface area.
Mite Description and Detection
House dust mites are tiny adults are about 0.5 mm long and the immatures are even smaller. Consequently, they generally are visible only with the aid of a microscope. The mites are globular in shape, clear to creamy white in color, with hairs on their legs and body.
How do I know if I have them in my bed? Mites aren't visible without a microscope, so instead, you have to analyze your symptoms. People who are allergic to them may experience sneezing, coughing, wheezing, watery eyes, difficulty breathing, nasal congestion, and itching.
Bed bug poop appears as clusters of tiny spots on your bed. The droppings consist of digested blood, so they will no longer be red once they dry. The spots will be darker, rust colored or black, and are about the size of a dot from a marker.
Before ingesting blood, the bed bug are rusty-brown to mahogany colored. After feeding their color changes to reddish-brown. Dust Mites have different ranges in color from tan, reddish-brown, and creamy blue to white.