Adverse Health Effects of Indoor Mold Exposure Overview of the 2011 ACOEM Statement Anthony Burton, MD MPH General Motors-Romulus

ACOEM 2011 Statement American College of Occupational and Environmental Medicine-founded 1916 Represents more than 4,500 physicians and other professionals in OEM “Adverse Human Health Effects Associated with Molds in the Indoor Environment”

ACOEM 2011 Statement A position statement of the college Prepared under auspices of the Council of Scientific Advisors Approved by the ACOEM Board of Directors on Revision of the 2002 position statement Evidence based

ACOEM 2011 Statement Includes: current state of scientific knowledge with respect to mold-related illness indoors Does not include: food-borne exposure; methods of exposure assessment; remediation procedures

Mold-Types of Health Effects Allergy Infection Toxicity

IgE Allergic Reactions to Mold IgE antibodies mediate an immediate hypersensitivity reaction causing allergic disease: runny nose and itchy eyes (hay fever), asthma Following exposure, sensitization occurs when IgE antibodies specific to fungal proteins are made Once sensitized, subsequent exposure can trigger allergic responses

IgE Allergic Reactions to Mold Molds are common and important allergens Atopic individuals (those with allergic asthma, rhinitis, eczema who have IgE antibodies to a range of environmental proteins) typically develop allergy to molds Reactions often also occur to other allergens (animal dander, dust mites, pollens, etc.)

IgE Allergic Reactions to Mold About 40% of the population is atopic (have allergic antibodies to aeroallergens) About ¼ of these (10% of the population) have antibodies to common aeroallergenic molds About ½ of these (5% of the population) will have allergic disease from molds

IgE Allergic Reactions to Mold Molds are much more abundant outdoors than indoors; outdoor exposures cause more allergic airway disease. Indoor exposures play an important but minor role Common indoor allergenic molds: Penicillium, Aspergillus Outdoor molds that can be found at high levels indoors: Cladosporium, Alternaria

IgE Allergic Reactions to Mold Damp/water damaged homes are associated with numerous health problems (especially in children): asthma, wheezing, cough, sputum production These health problems are likely related to more than just mold; bacteria, bacterial endotoxins, dust mites may all play a role in these problems

Hypersensitivity Pneumonitis An immunologically mediated hypersensitivity disease from inhalational exposure Patients frequently have circulating (IgG) antibodies detectable in blood directed against the etiological antigen Also called HP or “extrinsic allergic alveolitis”

Hypersensitivity Pneumonitis Most cases of HP are from occupational exposure Can result from exposures related to pet birds, humidifiers (humidifier fever), HVAC systems Most HP related to water sources are due to thermophilic actinomycetes (bacteria)

Hypersensitivity Pneumonitis Acute disease causes chills, fever, shortness of breath and malaise with onset 4 to 6 hours after exposure, lasting 18 to 24 hours Self-limited and reversible Mimics bacterial or viral pneumonia, but resolves quickly without antibiotics

Other Allergic Diseases Allergic bronchopulmonary aspergillosis and allergic fungal sinusitis Uncommon IgE mediated allergic disease caused by growth of fungi in the human airway; not linked to indoor environments Can occur in allergic individuals with existing airway damage Allergic reaction to fungal colonization

Allergy and Molds- Recommendations If you have allergic airway disease, minimize your exposure to mold and other aeroallergens by: – closing windows – filtering outdoor intakes – remediating sources of indoor mold amplification; controlling humidity – reducing exposure to animal allergens, dust mites, cockroaches

Allergy and Molds- Recommendations If hypersensitivity pneumonitis is suspected, need to investigate potential sources of inhaled antigen In the industrial environment, focus measures on preventing mold growth, e.g. –in metal-working fluids –where stored organic/agricultural materials are handled –reduce aerosol or particulate generation

Allergy and Molds-Summary For almost all allergic individuals, reactions to molds will be limited to rhinitis or asthma, and sinusitis may occur secondarily Other effects are rare

Mold Infections Indoor mold exposure does not generally lead to infection Some fungal infections can occur in healthy subjects: Blastomyces, Coccidioides, Cryptococcus, Histoplasma; though these are typically found only outdoors

Mold Infections Serious fungal infections (deep tissue invasion) are primarily restricted to severely immunocompromised subjects –fungi such as Aspergillus are ubiquitous, and Candida are human commensals –these, and the others that are typically found outdoors are not typically found growing indoors

Mold Infections Superficial fungal infections are very common in normal individuals; they cause ringworm, athlete’s foot, and other mucosal and skin infections Some of these can be found growing as indoor mold or on indoor pets Candida albicans can be cultured from > ½ the population with no evidence of active infection

Mold Infections-Recommendations Immunocompromised individuals require caution about exposure to opportunistic fungal infections Those with infections related to pets should have their pets checked by a veterinarian

Molds and Toxicity Mycotoxins: secondary metabolites of fungi, i.e., not required for growth or survival of the fungus Amount and type of mycotoxin production is highly variable, dependent on multiple factors Thus, presence of a toxigenic species does not necessarily mean presence of toxin

Mycotoxins Most descriptions of human poisonings from mold involve eating moldy foods Some cases involve agricultural worker exposure to high levels of silage or spoiled grain products that contain high concentrations of fungi, bacteria, and organic debris contaminated with endotoxins, glucans, and mycotoxins

MVOCs Microbial volatile organic compounds (MVOCs): low molecular weight aldehydes, alcohols, and ketones with low odor thresholds; cause the musty odor associated with mold and mildew

Sick Building Syndrome

An older term used to describe nonspecific building-related symptoms that cannot be associated with an identifiable cause

Building Related Symptom Nonspecific symptom that cannot be associated with an identifiable cause but that appears to be linked to time spent in a building. Mucosal irritation affecting the nose, throat and eyes Headache, irritability, fatigue, difficulty concentrating; chest tightness, pressure; skin irritation, dryness; nausea, diarrhea

Building Related Illness This is a diagnosable illness associated with indoor exposure with documented physical signs and laboratory findings Rhinitis, asthma, conjunctivitis, sinusitis Hypersensitivity pneumonitis

Building Related Complaints Illnesses such as rhinitis and asthma have clearly been associated with exposure to molds in the indoor environment Many symptoms are often attributed to occupancy in a building Investigation generally finds no specific cause for the reported symptoms, but molds are often implicated when found

Mycotoxins and Human Health

Stachybotrys chartarum (aka S. atra), a major focus of mycotoxicity Critical literature reviews concluded that indoor airborne levels of microorganisms are only weakly correlated with human disease or building-related symptoms and a causal relationship has not been established between these complaints and indoor exposures to S. chartarum

Stachybotrys chartarum Cases of pulmonary hemorrhage in infants in Cleveland in the 1990s initially attributed to S. chartarum Subsequent re-evaluations by CDC and expert panel concluded there was no causal link Illness now termed “acute idiopathic pulmonary hemorrhage in infants”

Mycotoxins and Human Health To cause adverse effects, mycotoxins must be present, there must be a route of exposure from source to susceptible person, with absorption of toxic dose over a sufficiently short period of time Presence of mycotoxins cannot be presumed from presence of toxigenic species

Mycotoxins and Human Health Pathway for exposure indoors involves dermal contact or by inhalation of aerosolized spores, mycelial fragments, or contaminated substrates Mycotoxins are usually large molecules, and therefore usually not very volatile; thus, aerosolization is required

Mycotoxins-Recommendations Presence of toxigenic mold indoors not sufficient evidence for presence of mycotoxins or that building occupants absorbed a toxic dose When mold colonization is present indoors, abate the source of moisture and remediate the mold growth

Mycotoxins-Recommendations Indoor air sampling coupled with contemporaneous outdoor sampling may help assess presence of indoor mold amplification as well as the extent of potential indoor exposure Bulk, wipe, wall cavity samples may indicate presence of mold but don’t tell you much about occupant exposures

Mycotoxins-Recommendations Individual health complaints associated with mold exposure require a thorough assessment, including diagnoses unrelated to mold A diagnosis of mycotoxicosis requires specificity: consistency between signs, symptoms with the potential mycotoxins present, their known biological effects, and at the exposure levels present

Summary Mold spores are present in all indoor environments and cannot be eliminated from them Normal building materials and furnishings provide ample substrate for mold growth; just add water and the mold can propagate

Summary When this occurs, it is mandatory to eliminate the source of water and eradicate the mold Mold growth indoors should not be tolerated Current scientific evidence does not support the existence of a causal relationship between inhaled mycotoxins indoors and adverse human health effects