Transcript 2DampSpaceMold.ppt

Damp Spaces and Mold
And now, for the rest of the story…
Also laden with: pollen, fungi, algae, and protozoa
Fungus as part of nature…
• Mold, type of fungus, is
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part of nature
Needs moisture, food
source
Types and amounts of
mold differ with time of
year, place, and other
factors
Some in all homes
Visible growth in home
indicates a moisture
problem
Key elements for mold growth
• Moisture
• Active leak
• Water intrusion
• High humidity
• Nutrition
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Wood
Paper (cellulose)
Wallpaper
Gypsum
Carpet
Insulation
Dirt
• Oxygen
• Needs to be present
• Temperature
• 59°F-86°F
• 95°F-122°F
• Light
• Acidity and pH
Testing for Mold
• Why?
• Better spend the
money for mitigation
• There is no one
“bad” type of mold
• Interpretation can be
controversial
• Storage/transport of
samples
• Tape method (visible mold)
• Culture methods
• Anderson samplers
• Cassela samplers
• Rodac plates
• Impingers
• Filters
• Microscopy (scanning and
epifluorescence)
• Polymerase Chain
Reaction (PCR) or ERMI
Contaminants that can cause allergy-like
symptoms
• Moisture related
• Mold
• Cockroach
• Bacteria
• Dust mites
• Non-moisture related
• Chemicals
• Pets
• Smoking
Studies and reports
• Building dampness and mold was associated with
30-50% increases in a variety of respiratory and
asthma-related outcomes (1)
• Wide range of respiratory health effects including
asthma development, asthma exacerbation,
current asthma, respiratory infections, upper
respiratory tract symptoms, cough, wheeze, and
dyspnoea. (2)
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Meta analysis of epidemiological studies in IOM by Fisk, Lei-Gomez, Mendel, 2007
WHO IAQ Guidelines on dampness and mold, 2009
From CDC Website Taken from IOM
Mendell and colleagues…
• Most recent meta-analysis published in EHP, data through
late 2009 and published in June 2011
• Evidence of association between indoor dampness-related
factors
• asthma development, exacerbation, current and ever asthma,
• dyspnea, wheeze, cough, respiratory infections, bronchitis, allergic rhinitis, eczema,
and upper respiratory tract symptoms;
• Data on indoor dampness and mold suggests causation of
asthma exacerbation in children;
• Current data does not support measurement of indoor
allergens, bacteria or mold– Instead, mitigate and prevent
indoor dampness;
• Hygiene hypothesis-• moderate exposures to certain microbial agents, especially at early ages, may
prevent allergies and allergic asthma;
WHO 2009
• Exposure to microbial contaminants is associated with:
• Respiratory symptoms
• Allergies
• Asthma
• Immunological reactions
• Individual species cannot be identified*
• Emissions include spores, cells, fragments of cells and VOCs
• People exposed to multiple agents simultaneously
• Problems with accurately measuring exposure
• Large number of symptoms from exposures
*Exception are common allergies to pollens, dust mites, pets, and pests
WHO Executive Summary
• Health risks addressed by considering
“dampness as the risk indicator”
• Remediation of dampness reduces adverse
health outcomes, including rare conditions*
• Public enemy #1: Spores, cells, fragments, and
volatile organic compounds
• Exposure to microbial contaminants is clinically
associated with respiratory symptoms, allergies,
asthma and immunological reactions.
*hypersensitivity pneumonitis, allergic alveolitis, chronic rhinosinusitis and allergic
fungal sinusitis
Health Problems Associated
With Mold Particles
• Allergies and Asthma
• 5-10% of people
• 40% of asthmatics
• Hypersensitivity
reactions in working
populations
• Irritant reactions
• Infections (rare)
• Toxic reactions?
Who is at most risk?
• Individuals with chronic respiratory disease;
(asthma; emphysema,COPD; bronchitis)
• Immune suppressed individuals may be at higher
risk for infection;
(transplant patients taking immuno-suppressive drugs; HIV
positive; other people with serious diseases that may
compromise the immune system)
• Candida and Aspergillus species continue to be
the most common cause of invasive fungal
disease in immune compromised individuals;
Mold Induced Illness—
occupational exposures
• Hypersensitivity pneumonitis
• Allergic lung syndrome (progressive)
• High exposures to mold and organic dust
• Relatively rare
(1% of exposed individuals develop disease)
• Farmer’s lung (moldy hay/grain)
• Bagassosis (moldy sugar cane/ molasses)
• Maple bark stripper’s disease
• Tobacco worker’s lung
• Mushroom workers
Farmer’s Lung
Accounts for more than 30% of adults disabled by
respiratory illness and mold is a key factor in
development of this disease;
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dusty fields or buildings
handling moldy hay
working in silos
feeding or working with feedstuffs
working in com silage
uncapping silos
cleaning grain bins
exposed to bird droppings or feather, hair, or fur dust
exposed to fish meal
Health: Mold Infections
• Histoplasma or
Cryptococus
• Rare in healthy people
• Source: Usually Bird or
Bat droppings
• Opportunistic
infections: weakened
immune system
• Bone Marrow Transplant
• Uncontrolled diabetes
• Medication for cancer or
transplant
• HIV+
“Toxic” mold
Molds are toxigenic, not “toxic” themselves
They produce “mycotoxins.” Mycotoxins can be:
• cytotoxic
• carcinogenic
• estrogenic
• neurotoxic
*From ingestion of mycotoxins (NAS 2000)
•Inadequate or insufficient evidence that inhalation of environmental
mold by healthy adults causes: fatigue, neuropsychiatric symptoms,
cancer, reproductive effects, rheumatologic and other immune
diseases, respiratory disease, asthma, etc.
•Mold does not need to be actively growing and “alive” to be an
allergen to people;
Mycotoxins
• Low molecular weight natural products that are secondary
metabolites produced by filamentous fungi;
• Readily airborne and respirable (<1um- 7um);
• Not clear whether or not levels found in damp buildings
are high enough to cause adverse health effects;
Examples:
Penicillium produces penicillin;
Aspergillus flavus produces aflatoxin;
Stachybotrys chartarum produces trichothecenes and
satratoxin
The Toxic Hype: Stachybotrys chartarum
• Called “black” or “toxic” mold in media;
• Acute idiopathic pulmonary hemorrhage– not
proven;
• High cellulose/low nitrogen content; (fiberboard,
gypsum board, paper, dust, lint)
• Needs lots of constant moisture for growth;
• Toxins in air
• Spores only sometimes have toxins
• Stachy doesn’t release many spores
Stachybotrys chartarum (atra)
continued…
• Remember: Jury is still out regarding
health risks for inhalation exposures to this
mold in the environment;
• Not uncommon;
• Other molds:
• appear black
• produce toxins
• Clean the same way as other molds
• Treat as any mold… need a healthy
respect for mold and health effects they
may cause;
Endotoxins
• Found in components of the outer membrane in Gram-
negative bacteria
• Composed of proteins, lipids and lipopolysaccharides
• “Toxin” on the cell wall is liberated as a result of cell
lysis
• Found in environments with dust particles or aqueous
aerosols
• Heavy exposure can cause respiratory symptoms
(1 3)- β-D-glucans
• From most fungi, some bacteria and most higher plants;
• Non-allergenic, water-insoluble structural cell-wall
components;
• Linked to chitin and mannan (proteins, lipids and
carbohydrates in the cell wall);
• Have immunomodulating properties that may affect
respiratory health;
Dampness and Health
WHO 2009
Continued
Dry
Water can enter a building through…
Plumbing leaks &
drainage problems
Home Moisture
Activity
U of MN Extension
Pints of water put into the air
• Shower ………………….................... 0.52/ 5 min.
• Clothes dry (vented outside)…………………. 0
• Clothes dry (hanging or inside vent) ………… 4.68- 6.18/ load
• Cooking (dinner for 4) ………………………….. 1.22 (1.58 gas)
• Boil (10 minutes, 6-inch pan)……………………. 0.48 cover /0.57 uncovered
• Storage of firewood indoors………… 400-800 (6 months)
• House plants (5- 7 plants)…………………… 0.86-0.96/ day
• Respiration (family of 4)………………………. 0.44/ hour
• Pilot light………………………………. 0.37 or less/day
• New construction……………………. 10+ /day
• Seasonal high outdoor humidity…… 64-249 /day
Perspective on Mold
• Mold may cause health problems
• Allergy-type symptoms are the most common
• People can react very differently to mold
• The color of the mold is irrelevant
• For the most part, mold is not regulated by the government
• By keeping your home dry, you can prevent mold growth
• Visible mold growth should NOT be tolerated in
occupied indoor areas
• Cleaning recommendations vary and one must consider:
• Amount of visible growth
• Materials affected
• Sensitivity of individuals in the household
Identify water problems
• Evidence of past water intrusion
• Discolored ceiling tiles from roof leaks or ice
dams
• Loose floor tiles
• Plumbing fixtures with leaks
• Musty odors
• Discolored basement carpet or carpet pad
• Moldy vents (HVAC system)
• Bathroom tiles and walls
• Windows
Neil Carlson- U of MN
Neil Carlson- U of MN
Neil Carlson- U of MN
Neil Carlson- U of MN
Use of biocides for mold mitigation
• The underlying moisture or water problem must
be fixed to prevent mold from returning;
• Thorough drying required before rebuilding;
• Bleach may be used to kill fungus/mold and
should be a part of disinfecting after flooding
situations (sewage contamination)
• ½ cup bleach per gallon of water
• never mix bleach with ammonia
• Remember: people can have allergic type
symptoms to both dead and living mold;
Biocides used to inhibit mold growth
• Can add health risk to individuals
• In particular, individuals who may be very sensitive
(immune compromised, chronically ill, very young,
very old);
• “Effectiveness” of chemicals is questionable
against the broad category of fungus/mold
• Primary method to prevent mold growth must
include moisture/water control!
Manage water and humidity…
• Repair leaks, clean moldy surfaces;
• Reduce indoor humidity to <50%
• Use exhaust fans (bathroom and kitchen)
• Maintain good drainage around foundation;
• If a water problem occurs, clean and dry items and
materials within 24-48 hours.
Global trends contribute to dampness and mold
• Energy conservation not properly implemented- tightened
envelope, ventilation deficiency, improper insulation
• Urbanization- building type and density, degradation of
housing, housing availability and social inequity
• Climate change- extreme weather conditions and shifting
of climate zones
• Quality and globalization of building materials and
components-construction concepts and techniques
(WHO 2009)
From the
New Yorker
Magazine