Did you know that mold in your house or workplace could affect your everyday life, slowly turning a healthy existence to one vulnerable to disease? Yes, it’s true.

Cladosporium is a common genus of fungi which can be found indoors and outdoors, growing on soil, moist surfaces or decaying organic matter. These fungi develop into dark pigmented colonies which release thousands of airborne spores. This type of mold can cause allergies, asthma and in rare cases severe infections with fatal outcomes.

If you have already spotted this mold in your home, office or anywhere else, don’t wait and call for expert help immediately. A comprehensive range of remedies is available to remove these harmful molds from your place.

If you wish to know more, keep reading. This article will review molds of the Cladosporium genus, their common habitats and possible health effects.

What is Cladosporium mold?

Cladosporium is a large genus of molds, consisting of over 700 varieties. However, only 169 are recognized as species [1]. They have cosmopolitan distribution and can develop on all sorts of organic debris, in soil, on food, paint, textiles and so on.

The colonies grow rapidly, are usually olive-gray to black in colour and have a velvety or cottony appearance. Many species are plant pathogens, some parasite on other fungal species, and several species are medically relevant and may cause lung mycosis, infections of the skin, nails and eyes [2].

Where can be Cladosporium mold found?

This type of velvety or powder like mold is not hard to find. In fact, they are quite common in indoor and outdoor environments, in both residential and commercial settings. In most cases, they develop in areas that are deprived from regular sunlight and air ventilation.

Places that are dark, damp and moist are ideal places for the growth of these molds. They grow well in areas with water leaks or damage, humid surfaces, and in heating or cooling ducts.

Cladosporium mycelium on bottles of wine
Cladosporium mycelium on bottles of wine

Furthermore, several species of Cladosporium are common plant endophytes and pathogens, meaning that they can easily grow on the leaves, flowers and sprouts of indoor and outdoor plants.

Most Cladosporium species grow optimally within a temperature range of 18-28°C. However, some species (including the common C. herbarum and C. cladosporioides) can even grow at temperatures below 0°C and have the ability to reproduce on frozen meat [3].

In fact, you probably have Cladosporium spores in your home without knowing it. Studies of air pollutants observed Cladosporium spores in all homes tested in Canada [4], and a similar study in the USA found Cladosporium spores in 70% of the homes they examined [5].

Considering the ubiquity of Cladosporium spores in the air around us, it is not surprising that this mold can also be found on the following types of surfaces, often undetectable by the naked eye:

  • Wooden surfaces
  • Fabrics
  • Wallpapers
  • Carpets/rugs
  • Window sills
  • Grills
  • Upholstered furniture
  • Faucets
  • Curtains
  • Floors
  • Walls
  • Attics
  • Bathrooms
  • Basements

And the list is endless.

Cladosporium mold statistics

As part of the data analysis presented inside our mold statistics resource page, we have calculated how often mold spore types appear in different parts of the indoor environment when mold levels are elevated. Below are the stats for Cladosporium:

Cladosporium statistics
Cladosporium statistics – how often Cladosporium mold appears whenever mold levels are elevated in the indoor environment

Mold statistics

Is Cladosporium mold dangerous and toxic?

Similar to many other species of mold, members of the Cladosporium genus can also cause harm to the human body, affecting people of all ages. The reactions and symptoms of exposure to this fungus might not be the same for everyone as it depends on their sensitivity. While some people may develop allergies or other serious reactions after encountering this mold, others may not.

Infants are especially sensitive to Cladosporium allergens. A skin test study observed an allergic reaction of the skin in 42% of children under the age of 4 [6].

Furthermore, Cladosporium sp. has been known to cause various types of phaeohyphomycosis, including subcutaneous infections, infections of fingernails and toenails (onychomycosis), and infections of the eye (keratomycosis). In serious cases, Cladosporium spores can germinate in the lungs and develop into fungal balls [2].

What symptoms are caused by Cladosporium mold?

There are many symptoms that can develop in response to prolonged Cladosporium exposure. In most cases the reactions are minor, but in rare cases the allergies and infections can be critical, requiring immediate medical supervision.

What are the health effects caused by Cladosporium mold?

When it comes to discussing the pathogenic reactions to Cladosporium sp. in human bodies, the list is quite long. Until the 90’s very little was known about this worldwide species of fungi and its health impact on immunocompromised and mold-allergic patients.

Petri dish: mixture of Trichoderma Cladosporium Penicillium
Petri dish: mixture of Trichoderma Cladosporium Penicillium

However, recent epidemiological research has shown that inhalation of the spores of this mold, an important source of allergens, can create many symptoms. According to the Mayo Clinic, if you live with mold all year through, you can expect the following symptoms to occur:

  • Roughness of skin
  • Stuffy and running nose
  • Sneezing
  • Coughing
  • Postnasal drip
  • Nose, eyes and throat itch
  • Asthma
  • Fungal sinusitis
  • Wheezing
  • Respiratory issues
  • Chest uneasiness and pain
  • Sinus headache
  • Pulmonary infections

Did you know that inhaling air with over 3000 C. herbarum mold spores per cubic meter can initiate a clinical emergency? For this reason, in many cases it is not advisable to deal with large mold infestations on your own.

What is Cladosporium allergy?

C. herbarum, the most significant allergenic species, has been shown to contain two major allergens: Cla h 1 and Cla h 2 [7].

As this fungus readily disperses its reproductive spores into the air, they can easily settle in a person’s terminal bronchi, alveoli and sinus cavities if inhaled regularly.

Cladosporium carrionii
Cladosporium carrionii

Being exposed to mold for a prolonged period and inhaling its spores can cause serious allergic reactions, including allergic fungal sinusitis.

Allergies of these types usually have the following symptoms:

  • Nasal blockage over a long time
  • Postnasal liquids
  • Recurring headaches

How to identify Cladosporium mold in your home?

Identifying the precise species of Cladosporium mold, and especially its dispersed spores, is not possible without a microscope.

Chances are that the mold will not be readily visible. Not only can the colonies be small and discreet, they often develop in hidden nooks and crannies, behind appliances and inside air ducts. However, they can be detected by smell as they impair the indoor air quality to a great extent. Also, testing your blood for mold antibodies may provide answers if you are concerned about your home being infested by mold.

However, enlisting the help of professional mold removal experts is often the easier option. We can conduct a thorough home inspection to identify the type of mold in your home and eradicate it completely using the latest technology.

We can find out the causes of this type of mold and suggest remedial measures to disinfect the inside and outside of your home, making your home mold free for years to come.

How do you get rid of Cladosporium mold?

Removing mold, especially deeply rooted Cladosporium clusters, is not a layman’s job. In many cases, previous experience is invaluable when it comes to analyzing the root causes, addressing the everyday concerns, and reviewing the health issues.

According to The American Academy of Allergy, Asthma and Immunology (AAAAI), mold counts can always change with the weather. Rains and high humidity can often stimulate mold colonies to release their spores into the air.

Professional mold testing inspectors can detect and remove any trace of mold through effective sampling, quantification and characterization methods. They can detect mold in locations you may not have seen in years.

In a nutshell, if you have mold at your home or work place, our advice is to get it removed as soon as possible. Their spores can be allergenic or pathogenic and can have a long term impact on your health.

Keep an eye on windows, plants, soil and other damp areas. Keep humidity below 50%. Keep windows and doors open in order to improve ventilation. Fix water damage promptly and most importantly, seek professional help to permanently remove mold from your dwelling.


  1. Bensch K, Braun U, Groenewald JZ, Crous PW (2012). The genus Cladosporium. Stud Mycol. 72(1):1-401.
  2. Howard DH (2003). Pathogenic Fungi in Humans and Animals. Marcel Dekker, New York. pp 579-580.
  3. Piecková E, Jesenská Z (1999). Microscopic fungi in dwellings and their health implications in humans. Ann Agric Environ Med. 6: 1–11.
  4. Fradkin A, Tobin RS, Tarlo SM, Tucic-Porretta M, Malloch D (1987). Species identification of airborne molds and its significance for the detection of indoor pollution. APCA J. 37: 51-53.
  5. Lumpkins ED, Corbit SL, Tiedeman GM (1973). Airborne fungi survey. I. Culture-plate survey of the home environment. Ann Allergy. 31: 361-370.
  6. Kauffman HF, Tomee JFC, van der Werf TS, de Monchy JGR, Koeter GK (1995). Review of fungus-induced asthmatic reaction. Am J Respir Crit Care Med. 151: 2109-2116.
  7. Swärd-Nordmo M, Smestad Paulsen B, Wold JK (1989). Immunological studies of the glycoprotein allergen Ag-54 (Cla h II) in Cladosporium herbarum with special attention to the carbohydrate and protein moieties. Int Arch Allergy Appl Immunol. 90(2):155-61.

Published: January 4, 2019 Updated: May 17, 2019

John Ward

Written by:

Account Executive
Mold Busters

Fact checked by:

Mold Busters

Charles Leduc

Looking for mold library dataset or machine learning algorithm for training your AI?

Mold Busters created an open-source library of microscopy images of various kinds of mold which are used to train machine learning algorithms. If you would like to get access to it, just fill out the form below and we will contact you shortly: