Toxic Black Mold Inspection, Testing, Removal, & Prevention
in Midwestern and Eastern USA and Canada by Environmental Hygienists and Industrial Hygienists Phillip & Divine Fry

Email   ►Phone USA 1-810-639-0523 or 1-480-310-7970
Toxic Mold Species Information Toxic Mold Pictures  Mold Health Effects  Mold Inspection 
Mold Removal  Mold Terms & Definitions  Mold Victim Rights  Site Map

To find a Certified Mold Inspector in your area, please visit: Mold Inspector. To find a Certified Mold Remediator or Mold Contractor, please visit:  Mold Remediator. To be trained and certified
as a
Certified Mold Inspector or Certified Mold Remediator
, please visit: Mold Instruction

Absidia Species

The U.S. Government's Occupational Safety and Health Administration [OSHA] lists the following as the health effects of Absidia mold: Allergen, Irritant, Hypersensitivity pneumonitis, Dermatitis.


Taxonomic Classifications

Kingdom: Fungi
Phylum : Zygomycota
Subphylum : Zygomycotina
Class : Zygomycetes
Order : Mucorales
Family : Mucoraceae
Genus : Absidia

  • Colonies mature rapidly and resemble coarse, gray wool or cotton candy. The reverse is white or light gray.
  • Frequently considered a contaminant in cultures, Absidia species are similar in microscopic appearance to Rhizopus, but rhizoids are internodal.
  • Rhizoids may be difficult to find, as in the case illustrated below.
  • Sporangia are slightly elongated spheres ranging from 20-120μ in diameter. Sporangiospores are round to oval and measure 3-4.5μ.

Absidia in slide culture. A cup-shaped columella (long arrow) supports a spherical sporangium (short arrow). Note also the pale tan sporangiospores (arrowhead) recently released from a sporangium.

Low power photomicrograph of 
in slide culture. Internodal rhizoids are not apparent here.

Above mycological photos and captions are courtesy of:

For more absidia mold pictures please visit or click on: Absidia Mold Picture

Description and Habitats
Absidia species are filamentous fungi that are cosmopolitan and ubiquitous in nature as common environmental contaminants. They are usually found in food, plant debris and soil, as well as being isolated from foods and indoor air environment. They often cause food spoilage like on decaying vegetables in the refrigerator and on moldy bread.

The genus Absidia currently contains 21 species. The most commonly isolated species is Absidia corymbifera. It is the only recognized pathogen among the other Absidia species. Some of the other Absidia species are Absidia coerulea, Absidia cylindrospora, Absidia glauca, and Absidia spinosa.

Health Effects
According to the study of Microbiology and Immunology On-line, the Absidia species is one of the three most common genera that can cause ZYGOMYCOSIS which also known as mucormycosis and phycomycosis.  Zygomycosis is an acute inflammation of soft tissue, usually with fungal invasion of the blood vessels. This rapidly fatal disease is caused by several different species in this class. The zygomycetes, like the Candida species, are ubiquitous and rarely cause disease in an immunocompetent host. Some characteristic underlying conditions which cause susceptibility are: diabetes, severe burns, immunosuppression or intravenous drug use. 

Another common health effect of Absidia species, is Rhinocerebral infections. This disease is frequently seen in the uncontrolled diabetic.

TYPICAL CASE: An uncontrolled diabetic patient comes to ER (may be comatose depending on the state of diabetes) and a cotton-like growth is observed on the roof of the mouth or in the nose. These are the hyphae of the organism. If untreated, the patient will die within a few hours or days. What do you do to help this patient first? Controlling the diabetic state is most important before administering amphotericin.

These fungi have a tendency to invade blood vessels (particularly arteries) and enter the brain via the blood vessels and by direct extension through the cribiform plate. Rhinocerebral infections are usually fulminant and frequently fatal. This is why they cause death so quickly.  
Absidia species may also cause mucorosis in immune compromised individuals. Mucurosis is an infection with tissue invasion by broad, nonseptate, irregularly shaped hyphae of diverse fungal species such as Absedia species. The sites of infection are the lung, nasal sinus, brain, skin and eye (Mycotic Keratitis-infection of cornea which can lead to blindness). Infection may have multiple sites. One species of Absidia which is the Absidia cormbifera has been an invasive infection agent in AIDS and neutropenic patients, as well as, agents of bovine mycotic abortions, and feline subcutaneous abscesses.

Macroscopic Features

Absidia corymbifera grows rapidly. The rapid growing, flat, woolly to cottony, and olive gray colonies mature within 4 days. The diameter of the colony is 3-9 cm following incubation at 25C for 7 days on potato glucose agar. The texture of the colony is typically woolly to cottony. From the surface, the colony is grey in color. The reverse side is uncolored and there is no pigment production. Absidia corymbifera is a psychrotolerant-thermophilic fungus. It grows more rapidly at 37C than at 25C. Its maximum growth temperature is as high as 48 to 52C. The growth of Absidia corymbifera is optimum at 35-37C and at a pH value of 3.0 to 8.0.

Microscopic Features

Similar to that of the other members of the class Zygomycetes, Absidia corymbifera has wide (6-15 m in diameter) nonseptate hyphae. A few septa may occasionally be present. Rhizoids are rarely observed. When present, the sporangiophores arise on stolons from points between the rhizoids, but not opposite the rhizoids. The sporangiophores are branched and arise in groups of 2-5 at the internodes. They often produce arches. Sporangiophores carry pyriform, relatively small (20-120 m in diameter) sporangia. A septum is usually present just below the sporangium in the sporangiophore. The sporangiophore widens to produce the funnel-shaped apophysis beneath the sporangium. The apophysis of Absidia corymbifera is very well-developed and typical. The columella, the tip of the sporangiophore that extends into the sporangium, is semicircular in shape and has a small projection on top. Upon dissolving of the sporangial wall, a short remaining collarette may be observed overlining the apophysis. The sporangiospores are one-celled, hyaline to light black, round to oval in shape, smooth or rarely echinulate on surface and 3-4.5 m in diameter. They are found in the sporangium and are released to the surrounding when the sporangium ruptures.

Laboratory Precautions

General laboratory precautions are required, no special safety measures needed.


In vitro susceptibility data reported so far are limited . MIC breakpoints for interpretation of in vitro susceptibility results have not been defined. Similar to the other members of the class Zygomycetes, amphotericin b appears as the sole antifungal drug which is consistently active against Absidia corymbifera . In general, it is resistant to azoles, including the newer derivatives such as voriconazole. flucytosine is also ineffective against Absidia corymbifera . Some strains may yield relatively low MICs of sordarin group of compounds. However, the significance of this finding is unclear.

In vivo response, on the other hand, largely depends on administration of full-dose amphotericin B therapy as well as extensive surgical debridement and correction of the underlying predisposing factors (such as immunosuppression and diabetic acidosis).

Do-It-Best-Yourself Mold Solutions

Phil can help you fix your own propertys mold problems at low-cost, more safely, and better-in- results than what is done by many mold inspectors and mold contractors.  How can Phil help you?

     1. Read Phils five plain-English,
mold advice books to master mold inspection, testing, removal, remediation, and prevention for your house, condo, apartment, office,  or workplace.

     2. Buy do-it-yourself, affordable mold test kits, mold lab analysis, video inspection scope, mold cleaner, and mold killer, for the  successful toxic and household mold inspection, mold testing, mold species identification and quantification, mold cleaning, mold removal, and mold remediation to find mold, kill mold, clean mold, and remove mold from your residence or commercial building.

     3. Get FREE mold advice, mold help, and/or answers to your mold questions, by emailing mold expert Phillip Fry at You can also email pictures of your mold problems in jpeg file format as email attachments.

The mycological information gathered and organized in this extensive research on different Pathogenic Molds was  sourced out from the list of informative websites below: | | | | | | | | | | | | | | | |

Browse these Webpages

[Home] [Mold Species] [Absidia] [Acremonium] [Alternaria] [Aspergillus] [Aureobasidium] [Basidiobolus] [Beauveria] [Bipolaris] [Blastomyces] [Candida] [Chaetomium] [Chysosporium] [Cladophialophora] [Cladosporium] [Coccidioides] [Conidiobolus] [Cryptococcus] [Cunninghamella] [Curvularia] [Drechslera] [Emmonsia] [Engyodontium] [Epidermophyton] [Exophiala] [Exserohilum] [Fonsecaeae] [Fusarium] [Histoplasma] [Lecythophora Species] [Madurella] [Microsporum] [Mucor] [Paecilomyces] [Paracoccidioides] [Penicillium] [Phialophora] [Phoma] [Rhinocladiella] [Rhizomucor] [Rhizopus] [Scedosporium] [Scopulariopsis] [Scytalidium] [Sporothrix] [Stachybotrys] [Trichoderma] [Trichophyton] [Verticillium] [Wallemia] [Wangiella dermatitidis] [Yeast]

Copyright 2002-2015 Environmental Hygienists All Rights Reserved   Updated Jan. 18, 2015