An Overview of Mold
(There’s Fungus Among Us)
Prepared by
Curt Speaker
PSU Environmental Health and Safety
May 2003
Mold in History
One of the earliest references to mold and
how to deal with it is found in:
The Bible
Leviticus 14:33-53
Mold
Simple, plant-like organisms that exist
everywhere in nature
 They are natures recyclers; they break down
complex materials into simpler compounds
 Not all molds are bad! They are responsible
for some cheeses, fermented beverages and
antibiotics (i.e., Penicillin)
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Mold Structure
More on Mold
To survive, mold needs moisture, an organic
substrate to use as food, and lack of sunlight
(generally)
 The presence of mold inside a building does
not signify a health hazard (remember, mold
is everywhere)
 Left unchecked, mold will grow and
proliferate very quickly
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Water Incursion
The unwanted entry of moisture into an
indoor environment
 Possible causes:
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leaks from roof, around window frames or
foundations
plumbing leaks
HVAC system malfunctions
sprinkler activation
condensation
Mold and Water
Mold cannot live without water
(but spores can)
 Mold growth with typically begin within 48
hours of a water incursion incident
 Therefore, prompt attention to water
incursion is critical!
 Mold can be like an iceberg - only a small
portion of it is visible

Water Incursion through Ceiling
Water Incursion through Wall
Mold caused by Roof Leak
Mold on Ceiling
Mold on Wall
Mold on Carpet Backing
Mold in Ductwork
An Extreme Case!
Health Effects of Mold
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Molds produce three major health effects
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allergic reactions
infection
toxicity
Many physicians do not believe that the
levels of mold found in indoor
environments can adversely effect human
health (dose versus response)
Allergic Reactions
Allergic Asthma
 Allergic Rhinitis (nasal inflammation)
 Watery Eyes
 Persons with these reactions are are also
likely to have allergic reactions to other
common allergens such as animal dander,
dust mites, wood, tree and grass pollens
 Effects ~5% of the population

Infection
Serious fungal infections effect a very small
number of people, generally those who are
severely immunocompromised
 Superficial fungal infections, such as
athlete’s foot and toenail fungus are
extremely common and are not serious
health threats

Mold Toxins (Mycotoxins)
Mycotoxins are by-products of mold growth
that are irritants or allergens in humans
 They are not volatile, do not evaporate, and
do not migrate through walls, floors or
ceilings
 They are distinct and different from
MVOCs with are responsible for musty,
disagreeable odors associated with molds

More on Mycotoxins
Mycotoxins, if eaten, can cause serious
poisoning in humans and animals
 The Salem Witch Trials of 1692 were likely
caused by a mycotoxin (LSD caused by
ergot, a mold of rye grain)
 To effect humans, mycotoxins must be
present, there must be a exposure pathway,
and their must be a sufficient dose
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Stachybotrys chartarum
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Also know as “black
mold”, “toxic mold”
or “fatal fungus” or
just “stachy”
Was originally
implicated in
pulmonary
hemorrhaging in
infants, but this was
disproven
It is NOT this!!!
Other Health Effects Possibly
Associated with Mold
Headache
 Fatigue
 Dizziness
 Nausea
 Skin Rashes
 CNS Effects, especially “Cognitive
Impairment”

The Melinda Ballard Case - a
toxic mold/legal landmark
Successful PR executive purchased a 22
room, 11,000 sq. ft. mansion in Dripping
Springs, Texas in 1997
 Minor (but undetected) plumbing leak
resulted in building-wide contamination
with Stachybotrys
 Husband, wife and child became sensitized
 Case settled for $32,000,000 (later reduced
to $4,000,000)

So, What About Testing?
Testing should never be the first step in
evaluating a mold problem
 Interpretation of results difficult
 No “official” standards for airborne mold
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>1000 cfu/m3 or >2X outdoor concentration
Types of mold found indoors should not
differ significantly from outdoors
 Airborne levels do not always correlate to
amounts of mold in area
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Other Pitfalls
Undetected water incursion can cause mold
growth behind walls, which cannot be
readily seen or dealt with
 Water incursion within ductwork is a
serious problem (often unseen)
 Types of mold and concentrations of mold
that may cause no health effects in most
people may be irritating to sensitive
individuals
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PSU Testing Equipment
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Biotest RCS
Centrifugal Air
Sampler
Draws known volume
of air through device
Uses different types of
agar for bacteria &
molds
Easy to use, practical
Other Tools
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Snake Eye Remote
Visual Inspection Tool
Capable of looking for
mold behind walls,
above ceilings, etc.
Requires only a 1.25”
access hole for camera
High quality video
images
Mold Abatement
Address the source of the water incursion
before beginning clean up of mold
 Porous surfaces very difficult to clean
 Removal often the only option for ceiling
tiles, drywall, carpeting
 Soap and water is usually sufficient, except
for sewage incursion, which requires
disinfection
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Large Scale Abatement
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Abatement of large
areas of mold damage
requires many of the
same work practices
used for asbestos (area
isolation, wet cleaning
methods, directional
air flow with HEPA
filtration)
PSU Water Incursion Policy
Being developed to ensure that all units
(Academic, HFS, Auxiliary Services, CES)
deal with water incursion the same way
 Establishes criteria for evaluating water
damage and remediation
 Taken from HMC policy and other
documents
 Will be distributed to Safety Council when
completed
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Conclusions
Water incursion must be dealt with
promptly and correctly to prevent mold
from becoming a problem
 Known health effects of mold
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allergic reactions
infection (rare)
toxicity
The jury is still out on other health effects
Conclusions
Do not believe the popular media reports
regarding “toxic mold”, “black mold”, etc.
 Testing is of some value, but not by itself
 EHS has the specialized equipment needed
to do testing
 Large scale abatement of mold must be
done like asbestos removal
 Water Incursion Policy in the works
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References
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“A Brief Guide to Mold, Moisture and Your
Home”, U.S. Environmental Protection Agency”,
2002
“Guidelines on Assessment and Remediation of
Fungi in Indoor Environments”, New York City
Department of Health and Mental Hygiene, 2002
“Water Incursion Check List Procedures”, The
Milton S. Hershey Medical Center, College of
Medicine, 2001