GOALS MOLDS - MyBasementDigoutmybasementdigout.com/downloads/mold/ducatman_molds.pdf · 1. Molds...
Transcript of GOALS MOLDS - MyBasementDigoutmybasementdigout.com/downloads/mold/ducatman_molds.pdf · 1. Molds...
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MOLDS
Alan M. Ducatman, MD, MScProfessor and Chair,
Department of Community MedicineWest Virginia University
School of Medicine
GOALS1. Recognize real disease outcomes
caused by mold.2. Discuss controversial claims that lack
a strong scientific basis.3. Point out that mold occurs in a
specific setting; it is both simple AND complex to detect.
4. Discuss why (and how) to abate.
GOALS
5. Review what clinicians think.
6. Show over 70 slides within one hour—and still have fun.
7. Get good links (not just on Wednesday).
Fungus Among Us
Fungi are eukaryotic, unicellular, or multicellular organisms that lack chlorophyll and therefore depend on external food sources. They are a ubiquitous and essential part of earth’s ecology as primary decomposers of organic matter.
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Common Species of Fungus
• Yeasts• Rusts• Smuts• Mushrooms• Puffballs• Bracket Fungi• Slime Molds
Mold
Molds are multicellular fungi
that grow as a mat of intertwined
microscopic filaments (hyphae).
Potential Mechanisms of Injury from Mold
AllergyInfectionToxicityOf these, allergy is by far the mostcommon. An estimated 10% of the U.S. population is allergic to some molds.
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Common Manifestations of Mold Allergy
• Dermatitis• Rhinitis• Cause and Exacerbation of Sinusitis• Asthma
Rarer Manifestations of Mold Allergy
• Hypersensitivity pneumonitis• Anaphylaxis• Allergic bronchopulmonary
aspergillosis
ABPA: Allergic Bronchiopulmonary Aspergillosis
• Individuals with previous lung damage, such as bronchiectasis, may be colonized with formation of mycetomas.
• Ongoing allergic reaction to fungal protein causes symptoms.
• Aspergillus is the best-known colonizer, but other fungi may colonize as well.
Aspergillus Versicolor
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Fungal Infections• Superficial
– Feet Tinea Pedis– Groin Tinea Cruris– Body Tinea Corporis– Nails Tinea Onchomycosis
• These may occur in the absence of immunocompromise, especially with poor circulation (Tinea onchomycosis) or obesity (Tinea cruris).
Systemic or Pulmonary Fungal Infections
• Blastomycosis (southern US)• Coccidiomycosis (southwestern US)• Cryptococcus (pigeon droppings)• Histoplasmosis (bird & bat droppings)• Aspergillosis (compost, grain)• Candida (antibiotics)
Other Fungal Infections
• Among immunocompromised individuals, these and other more exotic bacterial and fungal infections are possible.
Occupational Manifestations of Mold Allergy
• Mushroom Tenders’ Disease
• Paprika Pullers’ Disease
• Maple Bark Splitters’ Disease
• “Farmers’ Lung” (actually, thermophilic bacteria)
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Mold and Toxins 1011. Molds can evolve mycotoxins.2. Mycotoxins are created and
aerosolized under certain circumstances.
3. We do not know if/when those circumstances exist in home environments.
4. There are no standardized methods for measuring mycotoxins and mycotoxin exposure.
Toxic Metabolites Can Cause Respiratory Illness
• Fungi can emit endotoxins, glucans, and mycotoxins.
• Toxic metabolites are encountered as mixed organic dusts, including fungi and bacteria, growing together.
Toxic Metabolites Can Cause Respiratory Illness
• Can result in Organic Toxic Dust Syndrome, associated with acute febrile illness and shortness of breath.
• Usual setting is agricultural, often indoor hog processing.
Fungal Toxins of Socioeconomic Value
• Toxic metabolites are called mycotoxins.
• Some are clinically useful:* Penicillin* Cyclosporine
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Mycotoxins in Food: A Serious Problem
Exposure• Ergot in rye flour• Penicillium in rice• Fusarium in
overwintered wheat• Aflatoxin in peanuts
or grains (breads)• Zearalenone
Outcome• St. Anthony’s fire• Cardiac beriberi• Alimentary toxic
aleukia• Liver cancer
• Estrogenic syndrome
Toxic Food Metabolites Have Caused Historic Illness
• Ergot (rye fungus, Secale cornutum), an alkaloid, was a common cause of poisoning in the Middle Ages.
• Acute form characterized by vomiting, pain, diarrhea, cold skin, uterine hemorrhage (historic abortifacient), coma, and death in sensitized individuals.
• Chronic form characterized by gangrene.
Mold: An Outdoor Allergen
• Data from several countries indicate that childhood asthma emergency room visits increase on “thunderstorm days.”
• In a Canadian study, asthma ER visits increased from 8.6 during 919 days of calm weather, to 10 on 161 thunderstorm days (p <.05).
Mold: An Outdoor Allergen• Fungal spore concentrations doubled on
thunderstorm days, from 1,512 to 2,749/m3
– Most commonly detected molds were Cladosporium
• Grass pollen count did not increase.
• Ozone level also increases on thunderstorm days.
Dales RE et al. The role of fungal spores in thunderstorm asthma. Chest 2003;123:745-50.
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Compost and Mold• Concentrations of > 105/m3 colony-forming
units of thermophilic actinomycetes, molds, and total bacteria have been measured 200 meters from industrial compost sites, dropping to background levels (N.D.-103) by 500 meters’ distance.
Herr CEW et al. Effects of bioaerosol-polluted outdoor air on airways of residents: a cross-sectional study. Occup Environ Med 2003; 60:336-42.
Compost and Mold
• Residence within 200 meters of a compost facility was associated with cough (O.R. 6.59; 2.57-17.73) and other symptoms.
Herr CEW et al. Effects of bioaerosol-polluted outdoor air on airways of residents: a cross-sectional study. Occup Environ Med 2003; 60:336-42.
Allergy to Molds – Immediate• IgE-Mediated – Immediate hypersensitivity to
fungal proteins in spores or hyphal fragments can manifest as asthma or rhinitis.
• Affected individuals generally have other allergies as well.
• Most common: PenicilliumAlternariaCladosporiumAspergillus (also in cigarettes, marijuana)
Penicillium
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Allergy to Molds - Delayed• IgG-Mediated. • Can cause hypersensitivity
pneumonitis, a specific antibody response.
• Can occur with pet birds, humidifiers, air conditioning overgrowth, or structural growth.
Allergy to Molds - Delayed
• One cause is Thermophilius actinomyces, a filamentous bacterium.
• Immunoassays used to detect sensitivity. May be positive before onset of disease, and in asymptomatic individuals.
Mold Allergy and Pseudoscience
• Large body of web literature on “chronic candida” and “candida hypersentivity.”
• Virtually any laboratory immunology finding has been cited to support the existence of the syndrome.
Mold Allergy and Pseudoscience
• Patients who endorse the syndrome may also endorse chronic fatigue, chronic fibromyalgia, and multiple chemical sensitivity.
• It has long been known that the chronic candida syndrome is an epidemic of nonsense.
American Academy of Allergy and Immunology. Clinical ecology. J Allergy Clin Immunol 1986; 78:269-71.
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Real Science: Mold and Childhood Asthma
• Study Design: 880 newborns at high risk of asthma were followed prospectively by Yale University and the NY State Department of Health.
• Key Variables: socioeconomic status, housing characteristics, measured airborne fungal colony counts.
Real Science: Mold and Childhood Asthma
• Mold Outcomes: – Cladosporium (62%) and Penicillium (41%) were
commonly found. – Cladosporium was associated with water leaks.
• Health Outcomes: – Cough associated with visible mold (RR = 1.49;
CI: 1.18-1.88)– High Penicillium counts associated with wheeze
(RR = 2.15; CI = 1.34-3.46) and persistent cough (RR = 2.06; CI: 1.31-3.24)
Real Science: Mold and Childhood Asthma
• Data Source: Gent JF et al. Environ Hlth Perspect 2002; 110:A781-A786.
• Web Site: http://stanley.niehs.nih.gov/ehp/query.html– Search Mold and Respiratory Symptoms
and First Year (look for Dec. 10, 2002).
Mold and Asthma: Physiologic, not Cultural
• China-Yale study - 1209 children ages 6-10 from 25 schools in suburban Beijing
• Asthma risk increased if mold or fungi on ceiling or in child’s room (O.R. 1.8, C.I. 1.1-2.9)
• Other risks – ETS, coal for heat or cooking, dogs, cats, cockroaches, ratsZheng T, et al. Childhood asthma in Beijing, China: A population-based case-control study. Am J Epidemiol 2002; 156: 977-83.
Similar findings from Canada (Am J Epi 1991; 134:196-302) and Finland (Environ Hlth Perspect 2002; 110:543-57)
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Dust Samples and Allergy
• Indoor mold spore counts correlated with one of 3 objective measures of allergy in German school children– Positive skin-prick reaction– Specific IgE (CAP-RAST-FEIA; IgE>35KU/L– Physician-coded diagnosis of asthma
Dust Samples and Allergy• For Cladosporium and Aspergillus, exposure
>90th percentile increased risk– Cladosporium OR 2.93 (1.17-7.36)– Aspergillus OR 2.11 (1.22-3.65)
Indoor exposure to molds and allergic sensitization. Environ Hlth Perspect 2002; 110:647-53. http://ehpnet1.niehs.nih.gov/docs/2002/110p647-653jacob/abstract.html
Indoor Fungal Overgrowthas Cause of Allergy and Irritation:
A Moldy Idea?
• Mold Matters• Mechanisms
– Fungal Allergen– Irritants
Institute of Medicine – Indoor biologic exposures. In Clearing the air: asthma and indoor air exposures.Washington, DC: National Academy Press 2000: 105-122.
Detection of Mycotoxins• Historic approach (HPLC) is time-
consuming• Antibody-based ELISA (enzyme-linked
immunosorbent assay) testing markedly increased turnaround and decreased human input.
• Resulting decreased cost allows for epidemiologic-exposure basis for variety of toxins. Expect new information!
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Controversial Health Reports Following Home Mycotoxin
Exposure
• Pulmonary hemosiderosis• Cognitive impairment• Immunosuppression• Cancer• SIDS
Stachybotrys – Fatal Fungus?
• Cases of infant pulmonary hemorrhage in Cleveland led to a CDC proposal that the cause was Stachybotrys chartarum.1, 2
1 Update: pulmonary hemorrhage/hemosiderosis among infants—Cleveland, OH, 1996-96. MMWR 1997;46:33-35.
2 Etzel RA, et al. Acute pulmonary hemorrhage in infants associated with exposure to Stachybotrys atra and other fungi. Ann Pediatr Adolesc Med 1998; 152:757-62.
Stachybotrys – Fatal Fungus?
• Horses eating or bedding in moldy straw contaminated with S. chartarumhave experienced fatal hemorrhage.
• Exposed workers have experienced upper respiratory illness, fever, dementia, and leukopenia.
CDC Review of Data• Multidisciplinary task force has
identified methodologic problems in the Cleveland conclusions:
– Sampling strategy problems, including nonblinding.
– Unclear that S. chartarum > in case homes.
– Hemosiderosis clinical definition unclear (no iron deficiency).
• Verdict: “Not Proven”
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CDC Review of Data
• Worker and veterinary data of direct mold toxin health effects are related to high-dose environment.
• We do not have convincing evidence regarding exposures at indoor air levels.
Mold Allergy or Toxicity and Pseudoscience:
“Haunted by Mold”
• A public issue
• “It grows in the walls. It chokes your child and renders your husband senseless. It is your—and your insurer’s—worst nightmare.”
NY Times Magazine, August 12, 2001
Nonindustrial Mold and Epidemiologic Review Data
• “The studies we reviewed provide no evidence that increasing levels of viable mold exposure in nonindustrial work environments or dwellings are related to an increasing occurrence of asthma or to nose, eye, and skin symptoms; fatigue; or headache in the adult population, which may be due to inappropriate or insufficient measure of mold exposure.”
• Kilstad HA et al. Do indoor molds in nonindustrial environments threaten workers’ health? A review of the epidemiologic evidence. Epidemiologic Reviews. 2002; 24:203-17.
Nonindustrial Mold and Epidemiologic Review Data
• “No consistent indications . . . related fungal biomass to health effects; however, the studies were few. . . .”
• “These health problems more often are reported by adults working or living in buildings that have signs of indoor mold and dampness.”
Kilstad HA et al. Do indoor molds in nonindustrial environments threaten workers’ health? A review of the epidemiologic evidence. Epidemiologic Reviews. 2002; 24:203-17.
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Mold Contact Media
• Wood• Paper• Carpet• Foods
• Ceiling Tiles• Particle Boards• Grout• Cinder Blocks
Mold can grow on any substance. Typical substrates include:
• The Internet!
Detecting Mold
You may be able to see or smell
mold, but it is often invisible, and
even inaccessible (e.g., behind
walls and in air conditioning units).
Building Type, Moisture, and Mold
• Studies in Finland and New York state have found that concentrations of viable airborne fungi (including Penicillium, yeasts, and Cladosporium) are higher in wooden school buildings than in concrete buildings.
• Moisture damage did not affect viable concentrations in wooden buildings.
Building Type, Moisture, and Mold
• In concrete buildings, moisture damage resulted in higher concentrations of viable airborne fungi (Stachybotrys, Aspergillus, Cladosporium, and Actinobacter).
McKlin, et al. AIHAJ 2003; 64:108-116.
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Substrates: What Happens When We start with the Building?
• Study Design: Population survey in 80 buildings for work-related respiratory symptoms (wheeze, dyspnea, chest tightness, cough). The buildings were analyzed for environmental risk.
Substrates: What Happens When We start with the Building?
• Findings: Odds ratios for ¾ symptoms were 2.0 (1.0-3.9) for poor drainage in debris in the air intake 2.6 (1.3-5.2) for poor drainage of air conditioning drip pans. Significance for work symptoms increased among asthmatics.
Mendell MJ et al. Am J Ind Med 2003:43:630-41.
Moisture Damage –It’s Not All Mold!
• Mycobacteria are present in building materials of moisture-damaged buildings.
• May spread in indoor air, especially during maintenance, renovation, and demolition.
Mold May be a “Generic” Term• Cell-line laboratory evidence suggests that bacterial
overgrowth in buildings with moisture problems is more likely than mold to produce an immune response.
• Inflammatory response: Pseudomonas fluorescens> Streptomyces californicus > Bacillus cereus > Stachybotrys chartarum > Aspergillus versicolor >Penicillium spinulasum.
Huttinen V. et al. Production of protoinflammatory mediators by indoor air bacteria and fungal spores in mouse and human cell lines. Environ Hlth Perspec 2003;111:85-92.
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Efflorescence
• White, powdery, or crystalline substance on surface of concrete or cinder block.
• Occurs as water containing soluble salts evaporates, transporting salts to surface.
• Will continue as long as there is source of salts and water.
Mold as a Biologic Indicator?
• Mold present in damp environments.• Damp or water-damaged homes
associated with increased respiratory illness such as asthma, or chronic cough, especially in children.
• Unclear whether mold, or other organisms, are the culprits.
Burr ML. Health effects of indoor molds. Rev Envir Hlth 2001; 16:97-103.
Moisture and Exposure –It’s Not All Mold!
• M. terrae, recovered from a moisture-damaged building, cultured and installed in mice trachea, caused both subacute (6 hours – 3 days) and sustained (up to 28 days) inflammation in mice lungs.
Jussila J., et al. Mycobacterium terrae isolated from indoor air of a moisture-damaged building induces sustained biphasic inflammatory response in mouse lungs. Env Hlth Perspect 2002; 110:1119-1125.
Mold Sampling Strategies:Influence of Time-to-Culture
• The durability of Penicillium spores in impinger samples decreased as time to culture increased.
• In contrast, Candida cells survived in impinger samples, less so if refrigerated.
• Refrigeration immediately after collection may be desirable.
Lin WH, Li CS. AIHAJ 2003; 64:102-107
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Air Sampling Techniques for Molds: Filtration
Type• Button Aerosol
• Filters
• Liquid collection
Purpose• Inhalables, can be a
personal sampler, lightweight.
• Can be sized, used for endotoxins
• Preserves microorganism integrity, assists infectious disease investigators.
Air Sampling Techniques for Molds: Impacters
Type• Single
• Air-cell
• Wall sampling
Purpose• Easy to use and
calibrate. Direct to agar.
• Rapid collection to glass slides.
• Core punch sample to aircell cassettes.
Other Evaluative TechniquesType• Fiber optic• Moisture meters
• Pump kits
• Surface swab kits
Purpose• For hidden areas
• For moisture content of wood and building material
• Carpet sampling
• Surface sampling
Desirable Laboratory Characteristics
• Accredited by AIHA (Environmental Microbiology “EMLAP”).
• Phone advice about collection and shipping.
• Microscopic and PCR if a high degree of accuracy is needed.
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Mold Remediation• Authoritative guides for mold remediation
are available. All begin with removing moist substrate.– American Industrial Hygiene Association. Report
of microbial task force. Fairfax, VA: AIHA Press, 2001.
– EPA Office of Air and Radiation, Indoor Air Division. Mold remediation in schools and commercial buildings. Washington, DC: March 2001.
Mold Remediation
• Rapid drying of water intrusion -prevent mold growth.
• Interior fungal growth physically removed – fungal contamination of interior surfaces is unacceptable.
Mold Remediation
• Industrial hygienists will probably recommend respirators and personal protection for remediation – exposure may create sensitivity.
• Large jobs may get recommendations for contaminant barriers, negative pressure, HEPA air filtration, and decontamination areas – exposure may create sensitivity.
Efflorescence
• Stains can be washed with water or diluted muriatic acid.
• Stains represent some cause of water incursion, which may harbor mold.
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Mold Control = Moisture Control
• Repair leaky plumbing
• Immediately clean and dry water-damaged areas
Measures: Leaks, standing water in vents
Mold Control = Moisture Control
• Replace water-damaged building materials
• Reduce interior humidity via air conditioners, dehumidifiers
Measures: Leaks, standing water in vents
Mold Control = Moisture Control
• Slope ground away from structure.
• Establish functional below-ground drainage system.
Measures: Floods and interior seeps
Mold Control = Moisture Control
• Avoid building in flood-prone areas.
• Clear vegetation overgrowth, dehumidify, replace water-damaged materials.
Measures: Floods and interior seeps
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Mold Control = Moisture Control
• Install insulation to reduce condensation on cold surfaces.
• Vent moisture-generating sources (e.g., shower fan).
Measures: Condensation
Mold Control = Moisture Control
• Install vapor barriers between concrete floors and carpet.
• Install moisture breaks and capillary barriers in walls.
• Install roof vents.
Measures: Condensation
Cost-Effective Alternatives to Environmental Abatement?
• Air filtration appears to provide small, statistically significant improvements in symptom scores and sleep quality.
• No apparent change in medication use or pulmonary function.
• Wax on greenboard may reduce wicking compared to gypsum (drywall).
McDonald E, et al. Effect of air filtration systems on asthma. Chest 2002; 122:1535-42.
Preventive Strategies: Ductwork
• Fiberglass duct liners were less likely to display Aspergillus nigerovergrowth, after deliberate seeding, if they contained a biocide additive, especially if made with impermeable, smooth surfaces.
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Preventive Strategies: Ductwork
• Not all biocides were equally effective
• Treatments did not work in the presence of moisture and food supply
Source: Samini BS and Ross K. Appl Occup Environ Hyg 2003; 18:193-99.
AOEC Clinical Opinion Survey: What Do Doctors Think?
• Sufficient evidence to attribute mold effects to mycotoxins?
Yes No DNA20 42 5
Note: This addresses cause, not presence of health effects.
AOEC Clinical Opinion Survey: What Do Doctors Think?
• What is the cause of mold-related illness?
1. Allergic (43/67 ranked this first)2. Irritant3. Toxic
AOEC Clinical Opinion Survey: What Do Doctors Think?
• What is the message to transmit to employees if there is moisture or signs of moisture damage?A. Employees are likely to be ill and
should be evaluated.B. The building has a water problem that
needs to be remediated to prevent mold growth.
(53/67 chose this answer)
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Terms Disliked by Knowledgeable Clinicians
• “Toxic Mold”
• “Black Mold”
Hyphae (Links)
• Stachybotrys toxin: CDC and “not proven” http://www.cdc.gov/mmwr/preview/mmwrhtml/mm4909a3.htm
• National Center for Environmental Health (CDC-NCEH) on stachybotrysand other molds http://www.cdc.gov/nceh/airpollution/mold/default.htm
More Hyphae (More Food Links)
• California Dept. of Health – nice stuff for families and for doctors faced with serology misinformationhttp://www.dhs.cahwnet.gov/org/ps/deodc/ehib/EHIB2/topics/mold.html
Notes: ♣ Site opens slowly♣ Has nice link to practical “What
do I do?” fact sheet
Spores (Kiddy Links)
• The American Academy of Pediatricshttp://www.aap.org/policy/re9736.html
Note: ♣ Not up to date on the stachybotrys issue
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Mold Medicine
• EPA mold resources including links to remediation– Homes– Commercial Buildings
http://www.epa.gov/iaq/molds/index.html
Note: ♣ Links have great pictures
Other Links• Industrial hygienists
http://www.aiha.org/Governmentaffairs-PR/html/oomold.htm
• Accredited labswww.aiha.org/ (Go to Laboratory Services, and then to Accredited Listing)
• Clean-upwww.fema.gov/hazards/floods/andwww.nyc.gov/html/doh/html/epi/moldrpt1.html
Review
• Mold (and other microbial overgrowth) represents a health problem.
• Allergy is the key issue.
• There are debates about the role of toxicity, and a lot of pseudoscience.
• Water source needs to be stopped, and contamination removed or abated.