Commonly found in outdoor air, on many kinds of plants and foodstuffs and
prefers rotting farmland manure. It may be resistant to fungicides. Alternaria
is considered an occasional contaminant of water damaged building materials
which contain cellulose. Although Alternaria is a notable source of fungal
allergy, pathogenic infections are also reported infrequently.
There are a wide variety of species of Aspergillus. Some are considered
opportunistic pathogens and may cause pulmonary infections. Some members also
produce mycotoxins and have been implicated in causing allergic reactions and
hypersensitivity pneumonitis. Aspergillus type organisms are some of the first
fungi to grow on water-damaged materials and are frequently found in
water-damaged structures. Although they are commonly found in the outdoor
environment, the outdoor frequency is generally considered low.
This yeast-like fungus is commonly found on caulk or damp window frames in
bathrooms. Aureobasidium may be pink or black in color. Although it seldom
causes infections, it can be allergenic. This is one type of mold that is a type
of mildew. It will grow in cooler climates and along with Cladosporium is
commonly found growing on siding.
Survives in soil. A gram positive rod which is part of a large family of
organisms which are for the most part non-pathogenic for man.
Frequently associated with dry rot, Basidiomycetes are primarily mushrooms,
toadstools, puffballs, rusts and smuts. High levels of these spores can
contribute to allergies in indoor environments. Poria incrassata is a
particularly destructive fungal organism that falls into this classification.
Poria has resulted in the collapse of severely infested buildings.
Most commonly associated with plants, Botrytis can cause allergic asthma
after indoor exposure. High levels are likely to be found in greenhouses or
other indoor areas with high humidity and large numbers of plants.
This is a very common plant pathogen that is frequently found on lumber in
lumber yards and is built into most homes. It has not been well studied and has
not been reported to be pathogenic or a producer of mycotoxins or allergens.
Commonly found on deteriorating wood products, Chaetomium frequently emits a
musty odor and is frequently found on water-damaged drywall. Its health effects
have not been well studied, however some rare compounds have on occasion been
identified as mutagenic.
Cladosporium is the genera most frequently encountered in both outdoor and
indoor air. It is frequently found in elevated levels in water-damaged
environments. Some species may be resistant to certain types of treated lumber.
A secondary invader of plant materials, Epicoccum can grow at higher
temperatures than many fungi, allowing it to be a human skin pathogen. Colonies
produce a wide variety of colors depending on the food source. Although it may
be isolated from water damaged building materials, it is generally thought of as
a typical outdoor organism.
Found in soils and on plants worldwide, Fusarium can invade corn and barley
and produce toxins at lower temperatures than many fungi. Fusarium has affected
water-damaged carpets and a variety of other building materials, and can cause
infection in immunocompromised individuals. Its spores are typically slimy and
may be difficult to isolated from air samples. It has also been implicated in
exacerbation of allergies and asthma and may produce mycotoxins.
Gram Negative Rods
Group of bacteria commonly found in standing water or water saturated
structures. Most are opportunistic pathogens. Many species release endotoxins
that can cause headaches and allergic type reactions.
This mold is found worldwide and is frequently present in air samples. Mucor
commonly grows on dung and moist hay. It is fast growing opportunistic and may
cause rare infection in immunocompromised individuals. It is considered a mild
Penicillium species are common contaminants on various substances. This
organism causes food spoilage, colonizes leather objects and is an indicator
organism for dampness indoors. Some species are known to produce mycotoxins. The
health of occupants may be adversely affected in an environment that has an
amplification of Penicillium. Penicillium is one of the first fungi to grow on
water-damaged materials and has been implicated in causing allergic reactions
and hypersensitivity pneumonitis. It commonly produces a strong musty odor.
Found in decaying wood, soil, and plant material, Pithomyces is not known to
cause infections or major health problems in humans. It has been found growing
on paper but is not commonly found growing indoors.
Frequently found in house dust, soil, fruits, nuts, and seeds, Rhizopus often
grows in fruit and vegetable garbage, or in forgotten leftover food. Exposure to
large numbers of Rhizopus spores has reportedly caused respiratory
complications. Rhizopus can be an allergen and opportunistic pathogen for
immunocompromised individuals, especially those with diabetic ketoacidosis,
malnutrition, or severe burns.
A common contaminant that can cause toenail infections.
A common soil contaminant. Non-pathogenic to humans.
Stachybotrys grows well on extremely wet building materials containing
cellulose that have remained wet for more than a week. It produces mycotoxins
that can irritate skin and mucous membranes. One potent mycotoxin produced by
Stachybotrys is called satratoxin; it is also toxic when inhaled. Extreme care
should be taken when this organism is amplified indoors.
Opportunistic pathogen. It can survive and grow in nasal secretions and on
skin. Produces many toxins which contribute to pathogenicity. Coagulase positive
are considered potentially pathogenic.
Fungi that are not mature enough for speciation