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Guidelines
on Assessment and Remediation Excerpts from the New York City
Department of Health |
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EXECUTIVE SUMMARY On
May 7, 1993, the New York City Department of Health (DOH), the New York
City Human Resources Administration (HRA), and the Mt. Sinai Occupational
Health Clinic convened an expert panel on Stachybotrys atra in
Indoor Environments. The purpose of the panel was to develop policies for
medical and environmental evaluation and intervention to address Stachybotrys
atra (now known as Stachybotrys chartarum (SC))
contamination. The original guidelines were developed because of mold
growth problems in several New York City buildings in the early 1990's.
This document revises and expands the original guidelines to include all
fungi (mold). It is based both on a review of the literature regarding
fungi and on comments obtained by a review panel consisting of experts in
the fields of microbiology and health sciences. It is intended for use by
building engineers and management, but is available for general
distribution to anyone concerned about fungal contamination, such as
environmental consultants, health professionals, or the general public. We
are expanding the guidelines to be inclusive of all fungi for several
reasons:
Fungi are present almost everywhere in indoor and outdoor environments. The most common symptoms of fungal exposure are runny nose, eye irritation, cough, congestion, and aggravation of asthma. Although there is evidence documenting severe health effects of fungi in humans, most of this evidence is derived from ingestion of contaminated foods (i.e., grain and peanut products) or occupational exposures in agricultural settings where inhalation exposures were very high. With the possible exception of remediation to very heavily contaminated indoor environments, such high-level exposures are not expected to occur while performing remedial work. There
have been reports linking health effects in office workers to offices
contaminated with moldy surfaces and in residents of homes contaminated
with fungal growth. Symptoms, such as fatigue, respiratory ailments, and
eye irritation were typically observed in these cases. Some studies have
suggested an association between SC and pulmonary hemorrhage/hemosiderosis
in infants, generally those less than six months old. Pulmonary
hemosiderosis is an uncommon condition that results from bleeding in the
lungs. The cause of this condition is unknown, but may result from a
combination of environmental contaminants and conditions (e.g., smoking,
fungal contaminants and other bioaerosols, and water-damaged homes), and
currently its association with SC is unproven. The
focus of this guidance document addresses mold contamination of building
components (walls, ventilation systems, support beams, etc.) that are
chronically moist or water damaged. Occupants should address common
household sources of mold, such as mold found in bathroom tubs or between
tiles with household cleaners. Moldy food (e.g., breads, fruits, etc.)
should be discarded. Building
materials supporting fungal growth must be remediated as rapidly as
possible in order to ensure a healthy environment. Repair of the
defects that led to water accumulation (or elevated humidity) should be
conducted in conjunction with or prior to fungal remediation. Specific
methods of assessing and remediating fungal contamination should be based
on the extent of visible contamination and underlying damage. The simplest
and most expedient remediation that is reasonable, and properly and safely
removes fungal contamination, should be used. Remediation and assessment
methods are described in this document. The
use of respiratory protection, gloves, and eye protection is recommended.
Extensive contamination, particularly if heating, ventilating, air
conditioning (HVAC) systems or large occupied spaces are involved, should
be assessed by an experienced health and safety professional and
remediated by personnel with training and experience handling
environmentally contaminated materials. Lesser areas of contamination can
usually be assessed and remediated by building maintenance personnel. In
order to prevent contamination from recurring, underlying defects causing
moisture buildup and water damage must be addressed. Effective
communication with building occupants is an essential component of all
remedial efforts. Fungi
in buildings may cause or exacerbate symptoms of allergies (such as
wheezing, chest tightness, shortness of breath, nasal congestion, and eye
irritation), especially in persons who have a history of allergic diseases
(such as asthma and rhinitis). Individuals with persistent health problems
that appear to be related to fungi or other bioaerosol exposure should see
their physicians for a referral to practitioners who are trained in
occupational/environmental medicine or related specialties and are
knowledgeable about these types of exposures. Decisions about removing
individuals from an affected area must be based on the results of such
medical evaluation, and be made on a case-by-case basis. Except in cases
of widespread fungal contamination that are linked to illnesses throughout
a building, building-wide evacuation is not indicated. In
summary, prompt remediation of contaminated material and infrastructure
repair is the primary response to fungal contamination in buildings.
Emphasis should be placed on preventing contamination through proper
building and HVAC system maintenance and prompt repair of water damage. This document is not a legal mandate and should be used as a guideline. Currently there are no United States Federal, New York State, or New York City regulations for evaluating potential health effects of fungal contamination and remediation. These guidelines are subject to change as more information regarding fungal contaminants becomes available.
On
May 7, 1993, the New York City Department of Health (DOH), the New York
City Human Resources Administration (HRA), and the Mt. Sinai Occupational
Health Clinic convened an expert panel on Stachybotrys atra in
Indoor Environments. The purpose of the panel was to develop policies for
medical and environmental evaluation and intervention to address Stachybotrys
atra (now known as Stachybotrys chartarum (SC))
contamination. The original guidelines were developed because of mold
growth problems in several New York City buildings in the early 1990's.
This document revises and expands the original guidelines to include all
fungi (mold). It is based both on a review of the literature regarding
fungi and on comments obtained by a review panel consisting of experts in
the fields of microbiology and health sciences. It is intended for use by
building engineers and management, but is available for general
distribution to anyone concerned about fungal contamination, such as
environmental consultants, health professionals, or the general public. This
document contains a discussion of potential health effects; medical
evaluations; environmental assessments; protocols for remediation; and a
discussion of risk communication strategy. The guidelines are divided into
four sections: 1.
Health Issues; 2. Environmental Assessment; 3. Remediation; and 4. Hazard
Communication. We
are expanding the guidelines to be inclusive of all fungi for several
reasons:
Fungi
are present almost everywhere in indoor and outdoor environments. The most
common symptoms of fungal exposure are runny nose, eye irritation, cough,
congestion, and aggravation of asthma. Although there is evidence
documenting severe health effects of fungi in humans, most of this
evidence is derived from ingestion of contaminated foods (i.e., grain and
peanut products) or occupational exposures in agricultural settings where
inhalation exposures were very high.13,
14 With the possible
exception of remediation to very heavily contaminated indoor environments,
such high level exposures are not expected to occur while performing
remedial work.15
There
have been reports linking health effects in office workers to offices
contaminated with moldy surfaces and in residents of homes contaminated
with fungal growth.12,
16, 17, 18, 19, 20
Symptoms, such as fatigue, respiratory ailments, and eye irritation were
typically observed in these cases. Some
studies have suggested an association between SC and pulmonary hemorrhage/hemosiderosis
in infants, generally those less than six months old. Pulmonary
hemosiderosis is an uncommon condition that results from bleeding in the
lungs. The cause of this condition is unknown, but may result from a
combination of environmental contaminants and conditions (e.g., smoking,
other microbial contaminants, and water-damaged homes), and currently its
association with SC is unproven.21,
22, 23 The
focus of this guidance document addresses mold contamination of building
components (walls, ventilation systems, support beams, etc.) that are
chronically moist or water damaged. Occupants should address common
household sources of mold, such as mold found in bathroom tubs or between
tiles with household cleaners. Moldy food (e.g., breads, fruits, etc.)
should be discarded. This document is not a legal mandate and should be used as a guideline. Currently there are no United States Federal, New York State, or New York City regulations for evaluating potential health effects of fungal contamination and remediation. These guidelines are subject to change as more information regarding fungal contaminants becomes available.
1.1
Health
Effects Inhalation of fungal spores, fragments (parts), or metabolites (e.g., mycotoxins and volatile organic compounds) from a wide variety of fungi may lead to or exacerbate immunologic (allergic) reactions, cause toxic effects, or cause infections.11, 12, 24 There
are only a limited number of documented cases of health problems from
indoor exposure to fungi. The intensity of exposure and health effects
seen in studies of fungal exposure in the indoor environment was typically
much less severe than those that were experienced by agricultural workers
but were of a long-term duration.5-10,
12, 14, 16-20, 25-27
Illnesses can result from both high level, short-term exposures and lower
level, long-term exposures. The most common symptoms reported from
exposures in indoor environments are runny nose, eye irritation, cough,
congestion, aggravation of asthma, headache, and fatigue.11,
12, 16-20 The
presence of fungi on building materials as identified by a visual
assessment or by bulk/surface sampling results does not necessitate that
people will be exposed or exhibit health effects. In order for humans to
be exposed indoors, fungal spores, fragments, or metabolites must be
released into the air and inhaled, physically contacted (dermal exposure),
or ingested. Whether or not symptoms develop in people exposed to fungi
depends on the nature of the fungal material (e.g., allergenic, toxic, or
infectious), the amount of exposure, and the susceptibility of exposed
persons. Susceptibility varies with the genetic predisposition (e.g.,
allergic reactions do not always occur in all individuals), age, state of
health, and concurrent exposures. For these reasons, and because
measurements of exposure are not standardized and biological markers of
exposure to fungi are largely unknown, it is not possible to determine
"safe" or "unsafe" levels of exposure for people in
general. 1.1.1
Immunological
Effects Immunological
reactions include asthma, HP, and allergic rhinitis. Contact with fungi
may also lead to dermatitis. It is thought that these conditions are
caused by an immune response to fungal agents. The most common symptoms
associated with allergic reactions are runny nose, eye irritation, cough,
congestion, and aggravation of asthma.11,
12 HP may occur
after repeated exposures to an allergen and can result in permanent lung
damage. HP has typically been associated with repeated heavy exposures in
agricultural settings but has also been reported in office settings.25,
26, 27 Exposure to
fungi through renovation work may also lead to initiation or exacerbation
of allergic or respiratory symptoms.
1.1.2
Toxic
Effects A
wide variety of symptoms have been attributed to the toxic effects of
fungi. Symptoms, such as fatigue, nausea, and headaches, and respiratory
and eye irritation have been reported. Some of the symptoms related to
fungal exposure are non-specific, such as discomfort, inability to
concentrate, and fatigue.11,
12, 16-20 Severe
illnesses such as ODTS and pulmonary hemosiderosis have also been
attributed to fungal exposures.5-10,
21, 22 ODTS
describes the abrupt onset of fever, flu-like symptoms, and respiratory
symptoms in the hours following a single, heavy exposure to dust
containing organic material including fungi. It differs from HP in that it
is not an immune-mediated disease and does not require repeated exposures
to the same causative agent. ODTS may be caused by a variety of biological
agents including common species of fungi (e.g., species of Aspergillus
and Penicillium). ODTS has been documented in farm workers
handling contaminated material but is also of concern to workers
performing renovation work on building materials contaminated with fungi.5-10
Some
studies have suggested an association between SC and pulmonary hemorrhage/hemosiderosis
in infants, generally those less than six months old. Pulmonary
hemosiderosis is an uncommon condition that results from bleeding in the
lungs. The cause of this condition is unknown, but may result from a
combination of environmental contaminants and conditions (e.g., smoking,
fungal contaminants and other bioaerosols, and water-damaged homes), and
currently its association with SC is unproven.21,
22, 23 1.1.3
Infectious
Disease Only
a small group of fungi have been associated with infectious disease.
Aspergillosis is an infectious disease that can occur in immunosuppressed
persons. Health effects in this population can be severe. Several species
of Aspergillus are known to cause aspergillosis. The most common
is Aspergillus fumigatus. Exposure to this common mold, even to
high concentrations, is unlikely to cause infection in a healthy person.11,
24 Exposure
to fungi associated with bird and bat droppings (e.g., Histoplasma
capsulatum and Cryptococcus neoformans) can lead to health
effects, usually transient flu-like illnesses, in healthy individuals.
Severe health effects are primarily encountered in immunocompromised
persons.24, 28, 29
1.1.4
Medical
Evaluation Individuals
with persistent health problems that appear to be related to fungi or
other bioaerosol exposure should see their physicians for a referral to
practitioners who are trained in occupational/environmental medicine or
related specialties and are knowledgeable about these types of exposures.
Infants (less than 12 months old) who are experiencing non-traumatic
nosebleeds or are residing in dwellings with damp or moldy conditions and
are experiencing breathing difficulties should receive a medical
evaluation to screen for alveolar hemorrhage. Following this evaluation,
infants who are suspected of having alveolar hemorrhaging should be
referred to a pediatric pulmonologist. Infants diagnosed with pulmonary
hemosiderosis and/or pulmonary hemorrhaging should not be returned to
dwellings until remediation and air testing are completed. Clinical
tests that can determine the source, place, or time of exposure to fungi
or their products are not currently available. Antibodies developed by
exposed persons to fungal agents can only document that exposure has
occurred. Since exposure to fungi routinely occurs in both outdoor and
indoor environments this information is of limited value. 1.1.5
Medical
Relocation Infants
(less than 12 months old), persons recovering from recent surgery, or
people with immune suppression, asthma, hypersensitivity pneumonitis,
severe allergies, sinusitis, or other chronic inflammatory lung diseases
may be at greater risk for developing health problems associated with
certain fungi. Such persons should be removed from the affected area
during remediation (see Section 3, Remediation). Persons diagnosed with
fungal related diseases should not be returned to the affected areas until
remediation and air testing are completed. Except
in cases of widespread fungal contamination that are linked to illnesses
throughout a building, a building-wide evacuation is not indicated. A
trained occupational/environmental health practitioner should base
decisions about medical removals in the occupational setting on the
results of a clinical assessment.
The
presence of mold, water damage, or musty odors should be addressed
immediately. In all instances, any source(s) of water must be stopped and
the extent of water damaged determined. Water damaged materials should be
dried and repaired. Mold damaged materials should be remediated in
accordance with this document (see Section 3, Remediation). 2.1
Visual Inspection A
visual inspection is the most important initial step in identifying a
possible contamination problem. The extent of any water damage and mold
growth should be visually assessed. This assessment is important in
determining remedial strategies. Ventilation systems should also be
visually checked, particularly for damp filters but also for damp
conditions elsewhere in the system and overall cleanliness. Ceiling tiles,
gypsum wallboard (sheetrock), cardboard, paper, and other cellulosic
surfaces should be given careful attention during a visual inspection. The
use of equipment such as a boroscope, to view spaces in ductwork or behind
walls, or a moisture meter, to detect moisture in building materials, may
be helpful in identifying hidden sources of fungal growth and the extent
of water damage. 2.2
Bulk/Surface Sampling
2.3
Air Monitoring
2.4
Analysis of Environmental Samples
Microscopic
identification of the spores/colonies requires considerable expertise.
These services are not routinely available from commercial laboratories.
Documented quality control in the laboratories used for analysis of the
bulk/surface and air samples is necessary. The American Industrial Hygiene
Association (AIHA) offers accreditation to microbial laboratories
(Environmental Microbiology Laboratory Accreditation Program (EMLAP)).
Accredited laboratories must participate in quarterly proficiency testing
(Environmental Microbiology Proficiency Analytical Testing Program (EMPAT)).
Evaluation
of bulk/surface and air sampling data should be performed by an
experienced health professional. The presence of few or trace amounts of
fungal spores in bulk/surface sampling should be considered background.
Amounts greater than this or the presence of fungal fragments (e.g.,
hyphae, and conidiophores) may suggest fungal colonization, growth, and/or
accumulation at or near the sampled location.30
Air samples should be evaluated by means of comparison (i.e., indoors to
outdoors) and by fungal type (e.g., genera, and species). In general, the
levels and types of fungi found should be similar indoors (in non-problem
buildings) as compared to the outdoor air. Differences in the levels or
types of fungi found in air samples may indicate that moisture sources and
resultant fungal growth may be problematic.
In
all situations, the underlying cause of water accumulation must be
rectified or fungal growth will recur.
Any initial water infiltration should be stopped and cleaned immediately.
An immediate response (within 24 to 48 hours) and thorough clean up,
drying, and/or removal of water damaged materials will prevent or limit
mold growth. If the source of water is elevated humidity, relative
humidity should be maintained at levels below 60% to inhibit mold growth.31
Emphasis should be on ensuring proper repairs of the building
infrastructure, so that water damage and moisture buildup does not recur. Five
different levels of abatement are described below. The size of the area
impacted by fungal contamination primarily determines the type of
remediation. The sizing levels below are based on professional judgment
and practicality; currently there is not adequate data to relate the
extent of contamination to frequency or severity of health effects. The
goal of remediation is to remove or clean contaminated materials in a way
that prevents the emission of fungi and dust contaminated with fungi from
leaving a work area and entering an occupied or non-abatement area, while
protecting the health of workers performing the abatement. The listed
remediation methods were designed to achieve this goal, however, due to
the general nature of these methods it is the responsibility of the people
conducting remediation to ensure the methods enacted are adequate. The
listed remediation methods are not meant to exclude other similarly
effective methods. Any changes to the remediation methods listed in these
guidelines, however, should be carefully considered prior to
implementation. Non-porous
(e.g., metals, glass, and hard plastics) and semi-porous (e.g., wood, and
concrete) materials that are structurally sound and are visibly moldy can
be cleaned and reused. Cleaning should be done using a detergent solution.
Porous materials such as ceiling tiles and insulation, and wallboards with
more than a small area of contamination should be removed and discarded.
Porous materials (e.g., wallboard, and fabrics) that can be cleaned, can
be reused, but should be discarded if possible. A professional restoration
consultant should be contacted when restoring porous materials with more
than a small area of fungal contamination. All materials to be reused
should be dry and visibly free from mold. Routine inspections should be
conducted to confirm the effectiveness of remediation work. The
use of gaseous, vapor-phase, or aerosolized biocides for remedial purposes
is not recommended. The use of biocides in this manner can pose
health concerns for people in occupied spaces of the building and for
people returning to the treated space if used improperly. Furthermore, the
effectiveness of these treatments is unproven and does not address the
possible health concerns from the presence of the remaining non-viable
mold. For additional information on the use of biocides for remedial
purposes, refer to the American Conference of Governmental Industrial
Hygienists' document, "Bioaerosols: Assessment and Control." 3.1
Level I: Small Isolated Areas
(10 sq. ft or less) - e.g., ceiling tiles, small areas on walls
3.2
Level II: Mid-Sized Isolated Areas
(10 - 30 sq. ft.) - e.g., individual wallboard panels.
3.3
Level III: Large Isolated Areas
(30 - 100 square feet) - e.g., several wallboard panels. A
health and safety professional with experience performing microbial
investigations should be consulted prior to remediation activities to
provide oversight for the project. The
following procedures at a minimum are recommended:
If
abatement procedures are expected to generate a lot of dust (e.g.,
abrasive cleaning of contaminated surfaces, demolition of plaster walls)
or the visible concentration of the fungi is heavy (blanket coverage as
opposed to patchy), then it is recommended that the remediation procedures
for Level IV are followed. 3.4
Level IV: Extensive Contamination
(greater than 100 contiguous square feet in an area) A
health and safety professional with experience performing microbial
investigations should be consulted prior to remediation activities to
provide oversight for the project. The following procedures are
recommended:
3.5
Level V: Remediation of HVAC Systems
3.5.1
A Small Isolated Area of Contamination (<10 square feet) in the HVAC
System
3.5.2
Areas of Contamination (>10 square feet) in the HVAC System
A
health and safety professional with experience performing microbial
investigations should be consulted prior to remediation activities to
provide oversight for remediation projects involving more than a small
isolated area in an HVAC system. The following procedures are recommended:
When
fungal growth requiring large-scale remediation is found, the building
owner, management, and/or employer should notify occupants in the affected
area(s) of its presence. Notification should include a description of the
remedial measures to be taken and a timetable for completion. Group
meetings held before and after remediation with full disclosure of plans
and results can be an effective communication mechanism. Individuals with
persistent health problems that appear to be related to bioaerosol
exposure should see their physicians for a referral to practitioners who
are trained in occupational/environmental medicine or related specialties
and are knowledgeable about these types of exposures. Individuals seeking
medical attention should be provided with a copy of all inspection results
and interpretation to give to their medical practitioners. In
summary, the prompt remediation of contaminated material and
infrastructure repair must be the primary response to fungal contamination
in buildings. The simplest and most expedient remediation that properly
and safely removes fungal growth from buildings should be used. In all
situations, the underlying cause of water accumulation must be rectified
or the fungal growth will recur. Emphasis should be placed on preventing
contamination through proper building maintenance and prompt repair of
water damaged areas. Widespread
contamination poses much larger problems that must be addressed on a
case-by-case basis in consultation with a health and safety specialist.
Effective communication with building occupants is an essential component
of all remedial efforts. Individuals with persistent health problems
should see their physicians for a referral to practitioners who are
trained in occupational/environmental medicine or related specialties and
are knowledgeable about these types of exposures.
The
New York City Department of Health would like to thank the following
individuals and organizations for participating in the revision of these
guidelines. Please note that these guidelines do not necessarily reflect
the opinions of the participants nor their organizations.
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