Campuses: Twin Cities | Crookston | Duluth | Morris | Rochester | Other Locations


Home > Indoor Air QualityFungi In BuildingsFungal Glossary

Fungal Glossary

Absidia sp.

A zygomycete fungus. Reported to be allergenic (7). May cause mucorosis in immune compromised individuals (6). The sites of infection are the lung, nasal sinus, brain, eye and skin (6). Infection may have multiple sites (6).

Acremonium sp. (Cephalosporium sp.)

Reported to be allergenic (7). Can produce a trichothecene toxin which is toxic if ingested. It was the primary fungus identified in at least two houses where the occupant complaints were nausea, vomiting and diarrhea. Asexual state of Emericellopsis sp. , Chaetomium sp., and Nectripsis sp. (3). It can produce mycetomas, infections of the cornea and nails (6).

Alternaria sp.

Aw - 0.89. Conidia dimensions 18-83 x 7-18 microns (5). A very common allergen (7) with an IgE mediated response (17). It is often found in carpets, textiles (17, 5), and on horizontal surfaces in building interiors. Often found on window frames (17). Outdoors it may be isolated from samples of soil (17, 5), seeds and plants (17). It is commonly found in outdoor samples. The large spore size 20 - 200 microns in length and 7 - 18 microns in sizes, (17) suggests that the spores from this fungi will deposited in the nose, mouth and upper respiratory tract. It may be related to bakers asthma (17). It has been associated with hypersensitivity pneumonitis (E). The species Alternaria alternata is capable of producing tenuazonic acid and other toxic metabolites which may be associated with disease in humans or animals (5). Common cause of extrinsic asthma (immeadiate-type hypersensitivity: type I) (26). Acute symptoms include edema and bronchiospasms, chronic cases may develop pulmonary emphysema (26).

Aspergillus caesiellus

This species is only occasionally pathogenic (26).

Aspergillus candidus

Aw 0.75 (5). Conidia dimensions 2.5-4 microns (5). Found in warm soils, grain and in the secondary decay of vegetation (5). Associated with respiratory complaints in a recent house investigation. (MAC) Can produce the toxin petulin which may be associated with disease in humans and other animals (5).

Aspergillus carneus

This species is only occasionally pathogenic (26).

Aspergillus clavatus

Conidia dimensions 3-4.5 x 2.5-4.5 microns (5). Found in soils and animal manure (5). Can produce the toxin petulin which may be associated with disease in humans and other animals (5). This species is only occasionally pathogenic (26).

Aspergillus deflectus

This species is only occasionally pathogenic (26).

Aspergillus flavus

Aw 0.78 (5). Conidia dimensions 3-6 microns (5) or 3-5 microns (26). It grows on moldy corn and peanuts (5). It can be found in warm soil, foods and dairy products (5). Some strains are capable of producing a group of mycotoxins - in the aflatoxin group. Aflatoxins are known animal carcinogen. There is limited evidence to suggest that this toxin is a human carcinogen. The toxin is a poisonous to humans by ingestion. It may also result in occupational disease via inhalation (27). Experiments have indicated that it is teratogenic and mutagenic (20). It is toxic to the liver (1, 5, 27). It is reported to be allergenic (7). Its presence is associated with reports of asthma. It can be found in water damaged carpets (NC). The production of the fungal toxin is dependent on the growth conditions and on the substrate used as a food source. This fungus is associated with aspergillosis of the lungs (5, 26) andor disseminated aspergillosis (5). This fungus is occasionally identified as the cause of corneal, otomycotic and nasoorbital infections (26).

Aspergillus fumigatus

Aw 0.82 (5); Optimum > 0.97 (22). Conidia dimensions 2-3.5 microns (5). Major cause of aspergillosis (5, 26). Both invasive and allergic aspergillosis are caused by this organism (26). Aspergillosis affects individuals who are immune compromised. It is considered a human pathogen. It grows well at 35 degrees C. It is commonly found outdoors in compost piles with temperatures higher than 40 degrees C, in mild to warm soils and on cereals (5).

Aspergillus glaucus

Conidia dimensions 5-6.5 microns (5). Common outdoor fungus in the winter (NC). It is reported to be allergenic. This species is only occasionally pathogenic (26). It can grow on leather (NC). This fungus can grow at low moisture levels on grains, sugary food products, meat and wool (5). The ascomycetous state is Eurotium sp.

Aspergillus nidulans

Aw 0.78 (5). Conidia dimensions 2-4 microns (5). Found in mild to warm soils and on slowly decaying plants (5). Can produce the mycotoxin sterigmatocystin. This toxin has been shown to produce liver and kidney damage in lab animals. This fungus is associated with aspergillosis of the lungs andor disseminated aspergillosis (5). This species is only occasionally pathogenic (26).

Aspergillus niger

Aw 0.77 (5); Optimum > 0.97 (22). Conidia dimensions 3.5 - 5 microns (5) or 4 to 5 microns (26). Less common cause of aspergillosis. It has a musty odor. It is commonly found in the environment on textiles, in soils, grains, fruits and vegetables (5) . It has been reported to cause skin and pulmonary infections (26). It is a common cause of fungal related ear infections-otomycosis (5, 26).

Aspergillus ochraceus

Aw 0.77 (5). Conidia dimensions 2.5 - 3 microns (5). Found in grains, soil and salted food products (1, 5). It is not usually associated with decaying vegetation (5). Can produce a kidney toxin ochratoxin A which may produce ochratoxicosis in humans (1, 5). This is also known as Balkan nephropathy (1). The toxin is produced at optimum growth conditions at 25 degrees C and high moisture conditions. The ochratoxin may also be produced by other Aspergillus sp. and Penicillium sp. (1). Other toxins which can be produced by this fungus include penicillic acid, xanthomegnin and viomellein (5). These are all reported to be kidney and liver toxins (5).

Aspergillus oryzae

This species is only occasionally pathogenic (26).

Aspergillus parasiticus

Some strains are capable of producing a group of mycotoxins - in the aflatoxin group. Aflatoxins are known animal carcinogen. There is limited evidence to suggest that this toxin is a human carcinogen. The toxin is a poisonous to humans by ingestion. Experiments have indicated that it is teratogenic and mutagenic. (20) It is toxic to the liver(1). The production of the fungal toxin is dependent on the growth conditions and on the substrate used as a food source (1).

Aspergillus penicilloides

Conidia dimensions 3-3.5 x 4-5 microns (5). Can grow in areas with low water activity (5). It is found in house dust and food (5).

Aspergillus restrictus

This species is only occasionally pathogenic (26).

Aspergillus sp.

Aw 0.75 - 0.82 (5) Reported to be allergenic (7). Members of this genus are reported to cause ear infections (5). Many species produce mycotoxins which may be associated with disease in humans and other animals (5). Toxin production is dependent on the species or a strain within a species and on the food source for the fungus. Some of these toxins have been found to be carcinogenic in animal species. Several toxins are considered potential human carcinogens (20). Common cause of extrinsic asthma (immeadiate-type hypersensitivity: type I) (26). Acute symptoms include edema and bronchiospasms, chronic cases may develop pulmonary emphysema (26).

Aspergillus sydowi

This species is only occasionally pathogenic (26).

Aspergillus terreus

Aw 0.78 (5). Conidia dimensions 1.8-2.4 microns (5) or 2 - 2.5 microns (26). Aleurospores 6 - 7 microns in diameter are also produced (26). Found in warmer soil and in grains, straw. cotton and decomposing vegetation (5). Can produce the toxin patulin and citrinin which may be associated with disease in humans and other animals (5). This fungus is associated with aspergillosis of the lungs and or disseminated aspergillosis (5, 26). Found as an isolate from otomycosis - ear infection and onychomycosis - infection of finger or toe nails (26).

Aspergillus ustus

This species is only occasionally pathogenic (26).

Aspergillus versicolor

Aw 0.78 (5). Conidia dimensions 2-3.5 microns (5). It is commonly found in soil, hay. cotton and dairy products, It can produce a mycotoxin sterigmatocystin and cyclopiaxonic acid (5). These toxins can cause diarrhea and upset stomach. It is reported to be a kidney and liver carcinogen. This species is only occasionally pathogenic (26).

Basidiomycetes

Fungal spores which are from mushrooms. The specific mushroom species can not be identified on the culture plate. Many mushroom spores are reported to be allergenic (7).

Bipolaris sp.

A fungus with large spores which would be expected to be deposited in the upper respiratory tract. This fungus can produce the mycotoxin - sterigmatocystin which has been shown to produce liver and kidney damage when ingested by laboratory animals.

Blastomyces sp.

Human pathogen. The fungus is commonly found in soil. It is a dimorphic fungus which has filamentous fungus when grown at 25 degrees C and a yeast form at 37 degrees C.

Botrytis sp.

Aw 0.93 (5). Conidia dimensions 7-14 x 5-9 microns (5). Reported to be allergenic (7). It is parasitic on plants and soft fruits (17). Found in soil and vegetables (5). Possibly associated with allergic symptoms (skin tests) (17).

Candida sp.

Part of the normal flora of mouth and other mucous membranes in the body. Thrush and other diseases caused by Candida albicans usually occur after prolonged treatment with antibiotics or steroids. The environment is not a likely source of exposure for this fungus (17). Cells from the organism are usually not airborne (17). Reported to be allergenic (7).

Cephalosporium sp.

See Acremonium sp.

Chaetomium sp.

Large ascomycetous fungus producing perithecia (17). It is found on a variety of substrates containing cellulose including paper and plant compost.(17) It has been found on paper in sheetrock(NC). It is reported to be allergenic (7, 17). Can produce an Acremonium like state on fungal media (3).

Cladosporium fulvum (Fulvia fulva)

Conidia dimensions 12-47 x 4-10 microns (5).It is found on the leaves of tomatoes (5).

Cladosporium herbarum

Aw 0.88 (5). Conidia dimensions 5-23 x 3-8 microns (5). It is found on dead plants, woody plants, food, straw, soil, paint and textiles (5).

Cladosporium macrocarpum

Conidia dimensions 9-29 x 5-13 microns (5). It is found on dead plants, woody plants, food, straw, soil, paint and textiles (5).

Cladosporium sp. (Hormodendrum sp.)

Aw 0.88 (5); Aw 0.84 (21). Most commonly identified outdoor fungus. The outdoor numbers are reduced in the winter(NC). The numbers are often high in the summer (NC). Often found indoors in numbers less than outdoor numbers. It is a common allergen (7). Indoor Cladosporium sp. may be different than the species identified outdoors. It is commonly found on the surface of fiberglass duct liner in the interior of supply ducts. A wide variety of plants are food sources for this fungus (5, 17). It is found on dead plants, woody plants, food, straw, soil, paint and textiles (5). It can cause mycosis (17). Produces greater than 10 antigens (17). Antigens in commercial extracts are of variable quality and may degrade within weeks of preparation (17). Common cause of extrinsic asthma (immeadiate-type hypersensitivity: type I) (26). Acute symptoms include edema and bronchiospasms, chronic cases may develop pulmonary emphysema (26).

Cladosporium sphaerospermum

Conidia dimensions 3-4.5 microns (5). It is found as a secondary invader of plants, food, soil, paint and textiles (5).

Conidobolus sp.

Can cause a chronic inflammatory disease of the nasal mucosa (entomophthoromycosis) (6).

Cryptostroma corticale

Conidia dimensions 4-6.5 x 3.5-4 microns (5). Found on the bark of maple and sycamore trees and on stored logs (5).

Cunninghamella sp.

Can cause disseminated and pulmonary infections in immune compromised hosts (6).

Curvularia sp.

Reported to be allergenic (7). It may cause corneal infections, mycetoma and infections in immune compromised hosts (6).

Dreschlera sp.

Conidia dimensions 40-120 x 17-28 microns (5). Found on grasses, grains and decaying food (5). It can occasionally cause a corneal infection of the eye (6).

Epicoccum sp.

Conidia dimensions 15-25 microns (5). A common allergen (7). It is found in plants, soil, grains, textiles and paper products (5).

Epidermophyton sp.

Can cause infections of skin and nails (6).

Fusarium solani

Aw 0.90 (5). Macroconidia dimensions 27-52 x 4.4-6.8; Microcondia dimensions 8-16 x 2-4 microns (5). Found in plants and soils (5). Can produce trichothecene toxins which may be associated with disease in humans and animals (5).

Fusarium sp.

Aw 0.90 (5) A common soil fungus (17,5). It is found on a wide range of plants (5). It is often found in humidifiers (17). Several species in this genus can produce potent trichothecene toxins (5, 27). The trichothecene (scirpene) toxin targets, the following systems: circulatory, alimentary, skin and nervous (27). Produces vomitoxin on grains during unusually damp growing conditions. Symptoms may occur either through ingestion of contaminated grains or possibly inhalation of spores. The genera can produce hemorrhagic syndrome in humans (alimentary toxic aleukia). This is characterized by nausea, vomiting, diarrhea, dermatitis, and extensive internal bleeding (1). Reported to be allergenic (7). Frequently involved in eye, skin and nail infections (6).

Geotrichum sp.

Aw 0.90 (5). Conidia dimensions 6-12 x 3-6 microns (5). Aw 0.90 (5) A common contaminant of grains, fruits, dairy products, paper, textiles, soil and water (5), and often present as part of the normal human flora. The species Geotrichum candidum can cause a secondary infection (geotrichosis) in association with tuberculosis. This rare disease can cause lesions of the skin (5), bronchi (5) mouth, lung and intestine (5, 6).

Gliocladium sp.

A fungus which is structurally similar to Penicillium sp. It is reported to be allergenic (7).

Helminthosporium sp.

Reported to be allergenic (7).

Histoplasma sp.

A fungus which has filamentous growth at 25 degrees C and yeast growth at 37 degrees C. It is reported to be a human pathogen. It may be associated with birds.

Humicuola sp.

Grow on products with a high cellulose content (3). These fungi are also found in soil and on plant debris (3).

Hyaline Mycelia

Sterile mycelia which is white or transparent. No fruiting structures are produced by the mycelia. Visual identification of these organism is not possible. Often associated with allergic symptoms.

Microsporum sp.

Causes ringworm in humans (6).

Monilia sp.

Reported to be allergenic (7). This fungus produces soft rot of tree fruits (3). Other members produce a red bread mold (3). It is infrequently involved in corneal eye infections (6).

Mucor sp.

Often found in soil, dead plant material, horse dung, fruits and fruit juice. (17) It is also found in leather, meat, dairy products, animal hair and jute (17). A Zygomycetes fungus which may be allergenic ( skin and bronchial tests) (7, 17). This organism and other Zygomycetes will grow rapidly on most fungal media. May cause mucorosis in immune compromised individuals (6). The sites of infection are the lung, nasal sinus, brain, eye and skin (6). Infection may have multiple sites (6).

Nigrospora sp.

Reported to be allergenic (7).

Paecilomyces sp.

Commonly found in soil and dust, less frequently in air (17). P. variotii can cause paecilomycosis. Linked to wood-trimmers disease and humidifier associated illnesses(17). They are reported to allergenic (7). Some members of this genus are reported to cause pneumonia. It may produce arsine gas if growing on arsenic substrate. (3). This can occur on wallpapers covered with paris green (3).

Papulospora sp.

This fungi is found in soil, textiles, decaying plants, manure, and paper (3).

Penicillium sp.

Aw 0.78 - 0.88 (5) A wide number of organisms have placed in this genera. Identification to species is difficult. Often found in aerosol samples (17). Commonly found in soil, food, cellulose and grains (17, 5). It is also found in paint and compost piles. (5) It may cause hypersensitivity pneumonitis, allergic alveolitis in susceptible individuals. It is reported to be allergenic (skin) (7, 17). It is commonly found in carpet, wall paper, and in interior fiberglass duct insulation (NC). Some species can produce mycotoxins. Common cause of extrinsic asthma (immeadiate-type hypersensitivity: type I) (26). Acute symptoms include edema and bronchiospasms, chronic cases may develop pulmonary emphysema (26).

Periconia sp.

No information available, more to come.

Phoma sp.

A common indoor air allergen (7). It is similar to the early stages of growth of Chaetomium sp. The species are isolated from soil and associated plants (particularly potatoes) (17). Produces pink an purple spots on painted walls (3, 17). It may have antigens which cross react with those of Alternaria sp. (17). It will grow on butter, paint cement and rubber (3). It may cause phaeohyphomycosis a systematic or subcutaneous disease (6).

Pithomyces sp.

Grow on dead grass in pastures (3). Causes facial eczema in ruminants (1).

Rhizomucor sp.

The Zygomycetous fungus is reported to be allergenic (7). It may cause mucorosis in immune compromised individuals. It occupies a biological niche similar to Mucor sp. (17). It is often linked to occupational allergy (17). May cause mucorosis in immune compromised individuals (6). The sites of infection are the lung, nasal sinus, brain, eye and skin (6). Infection may have multiple sites (6).

Rhizopus sp.

The Zygomycetous fungus is reported to be allergenic (7). It may cause mucorosis in immune compromised individuals. It occupies a biological niche similar to Mucor sp. (17). It is often linked to occupational allergy (17). May cause mucorosis in immune compromised individuals (6). The sites of infection are the lung, nasal sinus, brain, eye and skin (6). Infection may have multiple sites (6).

Rhodotorula sp.

A reddish yeast typically found in moist environments such as carpeting, cooling coils and drain pans. In some countries it is the most common yeast genus identified in indoor air (17). This yeast has been reported to be allergenic (7). Positive skin tests have been reported (17). It has colonized terminally ill patients (6).

Saccharomyces sp.

Reported to be allergenic (7). Baker's Yeast.

Scopulariopsis sp.

It may produce arsine gas if growing on arsenic substrate. (3). This can occur on wallpapers covered with paris green (3). It has been found growing on a wide variety of materials including house dust. It is associated with type III allergy (17).

Serpula lacrymans

Common cause of extrinsic asthma (immeadiate-type hypersensitivity: type I) (26). Acute symptoms include edema and bronchiospasms, chronic cases may develop pulmonary emphysema (26).

Sporobolomyces sp.

Reported to be allergenic (7).

Sporothrix sp.

Can cause sporotrichosis. Usually only in populations which are immune compromised.

Sporotrichum sp.

Reported to be allergenic (7). See also Sporothrix sp. there is some taxonomic confusion between these two genera. This genera does not cause sporotrichosis.

Stachybotrys sp.

Aw - 0.94 , optimum Aw - >0.98 (22). Several strains of this fungus (S. atra, S. chartarum and S. alternans are synonymous) (1) may produce a trichothecene mycotoxin- Satratoxin H - which is a poisonous by inhalation. The toxins are present on the fungal spores. This is a slow growing fungus on media. It does not compete well with other rapidly growing fungi. The dark colored fungi grows on building material with a high cellulose content and a low nitrogen content. Areas with relative humidities above 55% and are subject to temperature fluctuations are ideal for toxin production (29).

Individuals with chronic exposure to the toxin produced by this fungus reported cold and flu symptoms, sore throats, diarrhea, headaches, fatigue, dermatitis, intermittent local hair loss (28) and generalized malaise. The toxins produced by this fungus will suppress the immune system affecting the lymphoid tissue and the bone marrow (1). Animals injected with the toxin from this fungus exhibited the following symptoms, necrosis and hemorrhage within the brain, thymus, spleen, intestine, lung, heart, lymph node, liver, and kidney. (29) Affects by absorption of the toxin in the human lung are known as pneumomycosis (1).

This organism is rarely found in outdoor samples. It is usually difficult to find in indoor air samples unless it is physically disturbed or if there is (speculation- a drop in the relative humidity). The spores are in a gelatinous mass. Appropriate media for the growth of this organism will have a high cellulose content and a low nitrogen content. The spores will die readily after release. The dead spores are still allergenic and toxigenic. Percutaneous absorption has caused mild symptoms (6).

There is controversy about toxigenic effects through inhalation of spores or mycelia. The following web sites cover both sides:

 

 

Stemphylium sp.

Reported to be allergenic (7). Isolated from dead plants and cellulose materials (3).

Syncephalastrum sp.

Can cause a respiratory infection characterized by a solid intracaitary fungal ball (26).

Torula sp.

Reported to be allergenic (7).

Trichoderma sp.

It is commonly found in soil, dead trees, pine needles, paper, unglazed ceramics (17). It often will grow on other fungi (17). It produces antibiotics which are toxic to humans (17). It has been reported to be allergenic (7, 17). It readily degrades cellulose (3).

Trichophyton sp.

Can cause ring worm, athlete's foot, skin, nail, beard and scalp (5, 6). Reported to be allergenic (7). Found on soil and skin (5).

Trichothecium sp.

Aw 0.90 (5). Conidia dimensions 12-23 x 8-10 microns (5). Found in decomposing vegetation, soil, corn seeds and in flour (5). The species Trichothecium roseum can produce a trichothecene toxin which may be associated with disease in humans and other animals (5). Reported to be allergenic (7).

Tritirachium sp.

Reported to be allergenic (7).

Ulocladium sp.

Aw 0.89 (21) Isolated from dead plants and cellulose materials (3). Found on textiles (3).

Verticillium sp.

Conidia dimensions 2.3-10 x 1-2.6 microns (5). Found in decaying vegetation, on straw, soil and arthropods (5). A rare cause of corneal infections (6).

Wallemia sp.

Aw 0.75 (5). Conidia dimensions 2.5-3.5 microns (5). Found in sugary foods, salted meats, dairy products, textiles, soil, hay and fruits (3, 5).

Yeast

Various yeasts are commonly identified on air samples. Some yeasts are reported to be allergenic (7). They may cause problems if a person has had previous exposure and developed hypersensitivity's. Yeasts may be allergenic to susceptible individuals when present in sufficient concentrations. (E)

Key:
Aw Water Activity (Equilibrium relative humidity/100)
E Paul Ellringer
MAC McGregor Pearce - personal experience
NC Neil Carlson - personal experience
(1-27) Refer to iaq_fib_fg_ref.htm Fungal iaq_fib_fg_ref.htm

N. Carlson 9/92; Rev. 4/93, 7/93, 9/93, 1/94, 2/94,2/95,4/95, 5/96, 7/96