Mold Standards for Exposure & Testing:

This InspectAPedia technical article describes various current & proposed mold standards as well as the very substantial shortcomings in any mold exposure standard whatsoever.

Here we also explain reasons for substantial variation in and interpretation of the meaning of airborne mold spore counts, moldy surface density, and other measures of the exposure level of allergenic, infectious, and levels of toxic mold in buildings.

At what level is allergenic or toxic mold considered a problem in buildings? How do we obtain an accurate and meaningful measurement of mold exposure indoors?

What mold spore levels indicate contamination in buildings ?

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Article Series Contents

• MOLD EXPOSURE STANDARDS
  • ASTM Mold Standards
  • AUSTRALIAN MOULD GUIDELINES - separate article
  • CALIFORNIA MOLD DISCLOSURE LAW- separate article
  • CANNABIS MOLD CONTAMINATION STANDARD
  • MOULD STANDARDS CANADA - - separate article
  • EUROPEAN UNION MOLD STANDARDS
  • NATIONAL ALLERGY BUREAU MOLD ALLERGEN LEVELS
  • NEW YORK CITY MOLD GUIDELINES- separate article
  • MOLD CFU CONTAMINATION LEVELS
  • OSHA GUIDE to WORKPLACE MOLD- separate article
  • WORLD HEALTH ORGANIZATION MOLD BULLETIN - separate article
• AIRBORNE MOLD SPORE COUNT GUIDE - home
• AIRBORNE PARTICLE LEVELS vs IAQ - home

Mold spore counts and mold culture results are not reliable alone for evaluating a mold problem

Warning: fungal spore counts in indoor air, whether "viable" or "non-viable" counts, as well as swab and culture methods to identify just what mold is present in a building are questionable methods to characterize the presence or absence of a mold problem indoors.

From experience carefully inspecting many buildings for mold problems and simultaneously collecting many types of field samples and examining them in our lab, our view is that anyone who makes one or a few indoor air measurements or relies on culture plates or swabs to "characterize" the mold level and mold species in a building is risking being way off target, particularly if the "test results" show low numbers.

Reasons Simple Airborne Mold Counts Alone Are Not Good Indicators of Risk

"Mold Levels" warning: single number "mold levels" are unreliable as a measure of health risk in buildings for several reasons including at least the following:

1. Particle levels vary:
   
   the actual level of indoor particles in air varies by several orders of magnitude over very short few-minute intervals, making reliance on any single measurement questionable, particularly if the measurement does not show evidence of a problem.
   
   Simple mechanical disturbance like turning on or off a fan can completely change individual measurement results. Short term measurements are therefore inaccurate.
2. Human sensitivity varies:
   
   because of wide variation in individual human reaction and risk to mold, variation in allergenicity, pathogenicity, and toxicity among mold genera and individual species, and even additional variation in these levels depending on specific environmental conditions such as the substrate upon which a mold is growing (its food), quantitative risk-levels are better used as an overall indication of building cleanliness before and after a mold cleanup, and not as an absolute level of risk to building occupants.
3. Particle toxicity varies:
   
   There is very wide variance among the toxicity of individual mold species, ranging from none to probably highly toxic, pathogenic, or even carcinogenic.
4. Spore size or mass varies
   
    widely from less than 1 u to over 200u, so a large spore contains potentially more harmful material than a small spore of the same "toxicity," making a "count" that does not identify the particle and particle size ambiguous
5. Mold spore toxicity varies,
   
   even within an individual species, depending on what substrate the species is growing on in a particular instance, e.g. wood vs. drywall. For background on how and why molds can be toxic,
   
   see this World Health Organization MOLD BULLETIN
6. Viable vs. non-viable "spore counts" vary in significance:
   
   procedures that use cultures to identify "viable" spores may omit high levels of non-viable spores which nonetheless remain highly toxic.
   
   Methods that rely on culturing have a high risk of identifying a mold which is present but is not the dominant or even the most problematic mold in the building, while completely failing to disclose a problem mold which is present but which simply does not grow in the culture media used, or is overgrown by another species in that media.
   
   For more details
   
   see AIRBORNE MOLD COUNT VALIDITY - Mold Spore Counts: are indoor fungal spore counts valid? for further explanation.

See ACCURACY OF AIRBORNE MOLD SPORE COUNTS for more details about these issues. That said, here is a sampling of some indoor air mold spore exposure level criteria and comments

Contamination levels of non-specific allergenic, pathogenic, or toxic fungal spores

1. Baxter et als:

Mold contamination is considered present in a building when the total mold spore concentration per cubic meter is above 10,000.

Our own field and lab experience confirms this view. However in special cases, even low quantitative levels of certain particles or particle types (such as Pen/Asp spore chains in an untreated building) may be diagnostic and may indicate a hidden mold reservoir that at least merits further investigation.

2. The National Allergy Bureau,

reporting the NAB SCALE (National Allergy Bureau) of mold and pollen counts, considers mold counts in outdoor air of 0-6499 spores per cubic meter of air as low, to 6500 to 12,999 spores per cubic meter of air as moderate, to 13,000 to 49,999 spores per cubic meter of air as high, and above 50,000 as very high.

At "high" levels most individuals with any sensitivity will experience symptoms.

AAAAI also provides absent, low, moderate, high, and very-high level level definitions for grass, tree, and weed pollen grains counted per cubic meter of outdoor air.

Acceptable levels for individual species vary since species toxicity varies widely as does spore size, weight, and other features which affect risk to building occupants. E.g. Aspergillus/Penicillium in a "clean" residential building study was at a mean of 230, in buildings known to have a moisture or flooding problem it was at 2235 and in mold contaminated buildings the figure was 36,037.

AAAAI provides an important qualification about mold and pollen counts as reported by that agency which we quote just below:

"These mold levels were determined based on outdoor exposure to natural occurring spores in the environment and should not be applied to indoor exposure which may represent an entirely different spectrum of spore types.

These definitions would allow comparison between sites across the country. They are based on ecological measurements, not health effects. However, assuming dose/response relationships are the same across the country, the definitions are probably more appropriate than a definition based on local numbers. This does mean that, for some stations, some categories will never be high." - AAAAI.

3. The University of Minnesota

data presents this table for mold levels expressed in colony forming units per gram described just below at

MOLD CFU CONTAMINATION LEVELS

 

Mold Spore Concentration Levels vs Allergies

Notes to the table above

• These numbers are for airborne spore concentrations per cubiic meter of air.
  
  Watch out: airborne mold measurements are usually very inaccurate and may vary by four orders of magnitude depending on small changes in air sampling test conditions.
  
  See details at AIRBORNE MOLD COUNT VALIDITY
• Definitions of Mold Spore or Fragment Allergy Hazard Levels
  
  Absent = no allergic reaction, no symptoms
  
  Low = Only individuals who are extremely sensitive to these pollens will experience symptoms
  
  Moderate = Many individuals with any sensitivity to these pollens will experience symptoms
  
  High = Most ndividuals with any sensitivity to these pollens will experience symptoms
  
  Very High = Almoste all individuals with any sensitivity at all to these pollens will experience symptoms, and extremely-senitive people could have severe symptoms
• Watch out: we have observed that individual sensitivity to mold spores, hyphal fragments and MVOCs varies significantly; some highly-sensitive individuals may experience severe allergic reactions to very low levels of mold spores or MVOCs and some individuals, including the author [DF] have experienced a very high allergic or asthmatic response to very specific individual mold genera/species.
  
  Chronic exposure or even a single-event extremely-high exposure to specific molds can cause highly-specific allergic reactions in individuals. The author became so sensitized to Memnoniella echinata following a single acute exposure during a building investigation.
  
  Memnoniella echinata referred to as S. memnoniella in some texts, is a member of the Stachybotrys mold family that includes S. chartarum, a widespread fungus that attacks cellulosic materials like paper as well as some fabrics and even wool.
• Source: National Allergy Bureau & AAAIA

 

Concentration Qualitative Assessment of Mold Contamination Levels

Watch out: mold spores may be not viable (dead), wrong culture media may be used, or one species can overgrow another, etc. And by some estimates as much as 90 to 95% of mold genera/species will not grow in any culture media so even if their spores fall onto a culture plate, those spores don't produce any colonies, but may be toxic if inhaled (such as some species of Penicillium).

So we would not rely on culture data as the sole or even primary building screening test for mold contamination. But here it is:

Colony Forming Units/gram - cultured mold samples as indicators of mold level in buildings

• less than 10,000 CFUs of mold per gram in a culture sample plate = low mold contamination level
• 10,000 to 100,000 CFUs of mold per gram in a culture sample plate = medium mold contamination level
• 100,000 to 1,000,000 CFUs of mold per gram in a culture sample plate = medium to heavy mold contamination level
• > 1,000,000 CFUs of mold per gram in a culture sample plate = heavy

WARNING: about interpreting mold cultures: this is a very very inaccurate method for screening buildings for the level of mold contamination for many reasons, including that only 10% of all molds will grow on any culture under any condition. So this approach begins as 90% "wrong".

Other mold level variables include the differences in settlement rate out of air as a function of particle size and weight, proximity to a mold contamination reservoir, and the problem that a serious toxic mold may be overgrown (if it grows at all) in the culture by a second mold species which hides the first one.

See INDOOR AIR QUALITY METHODS COMPARED for details of these issues.

4.The American Conference of Government Industrial Hygienists (ACGIH) stated (Harriet Burge et. al) stated in 1987 that indoor mold levels are generally less than 1/3 the outdoor level and that when indoor mold is at more than this level remedial action should betaken to find the source of the elevated counts and to clean it up.

Watch out: this is an inaccurate and unreliable method for screening buildings for mold for many reasons, including:

• The airborne level of particles varies enormously
  
  moment to moment - opening a door or closing a window, waving a notebook at a table, or walking across a carpet completely change the particle level
• Air exchange rate effects
  
  at most of our detailed investigations we find that unless all of the building windows are open and wind is blowing through the building, the air exchange rate between indoor and outdoor air confounds a comparison with outdoor air
• Outdoor air particle levels and mold levels vary enormously
  
  as a function of weather conditions; with snow cover there is little airborne mold outdoors; after a rain or at certain other weather conditions there can be an explosion in the level of outdoor spores, confounding the indoor measurement
• Importance of mold genera/species
  
  many if not most indoor/outdoor airborne mold level comparisons fail to focus on differences in genera and species between indoors and outside; even relatively low indoor airborne or dust-borne mold levels might indicate a problem in the building, depending on just what is identified in the sample
• Indoor and outdoor basidiomycetes
  
  are often mistaken for and compared with Penicillium/Aspergillus levels - a serious error

See INDOOR AIR QUALITY METHODS COMPARED for details of these issues.

5. Other proposals for Mold Exposure Standards have included a limit of 500 CFU/ of mold spores per cubic meter of air in winter indoors in sub arctic climates (Reponen et al.1990). CFU means "colony forming units" of mold.

We suspect that focusing only on "colony-forming-units" (that is, viable mold that will grow) is not a very reliable way to check out a building. That's because

• 90% of mold species will not grow on culture media
• Even if a particular mold species will grow on culture media, it may be overgrown
  
  and thus under-represented by a another mold that was present in the same sample at a much lower rate but which happens to like the culture media better than the more frequent spore or even a more toxic mold spore
• Spores settle out of air at very different rates
  
  depending on spore size and mass. Just as some very small snakes are more venomous and potentially dangerous than some very big snakes, size, and thus settlement rate out of air, and thus occurrence on a mold culture settlement plate, does not accurately represent what building occupants are breathing.

At MOLD CULTURE PLATE TEST ERRORS we have cited the range of errors and limitations of using cultures to check for viable mold, and we point out that depending on the particular mold genera and species present in a building, even non-viable mold may be allergenic or toxic.

That is why experts in mold testing and remediation advise that the object is to remove mold or clean up mold in a moldy indoor environment, rather than attempting to "kill" mold indoors.

Also see INDOOR AIR QUALITY METHODS COMPARED for details of these issues.

Mold Exposure Levels - Sources of Variation in Mold Toxicity - a warning about single numbers

Single number "mold levels" are very unreliable as a measure of health risk in buildings for several reasons including at least the following:

Particle levels vary widely over short time periods

The actual level of indoor particles in air varies by several orders of magnitude over very short few-minute intervals, making reliance on any single measurement questionable, particularly if the measurement does not show evidence of a problem.

The absolute level of airborne particles in buildings varies enormously, possibly by a factor of hundreds to thousands, over intervals as short as a few minutes. Simple mechanical disturbance like turning on or off a fan can completely change individual measurement results.

Short term measurements are therefore inaccurate and even longer term measurements are inaccurate if they do not consider the in-use variations in dust disturbance in a building.

Human sensitivity to mold varies

Individual susceptibility to mold/mycotoxin/aflatoxin-related or allergy-related illness varies widely and human exposure is complex because people move among a variety of environments

Finally, because of wide variation in individual human reaction and risk to mold, variation in allergenicity, pathogenicity, and toxicity among mold genera and individual species, and even additional variation in these levels depending on specific environmental conditions such as the substrate upon which a mold is growing (its food), quantitative risk-levels are better used as an overall indication of building cleanliness before and after a mold cleanup, and not as an absolute level of risk to building occupants.

Mold Spore - Particle toxicity varies for many reasons

There is very wide variance among the toxicity of individual mold species, ranging from none to probably highly toxic, pathogenic, or even carcinogenic

Mold Spore size varies widely from less than 1 u to over 200u, so a large spore contains potentially more harmful material than a small spore of the same "toxicity," making a "count" that does not identify the particle and particle size ambiguous

Mold spore toxicity may vary, even within an individual species, depending on what substrate the species is growing on in a particular instance, e.g. wood vs. drywall.

Viable vs. non-viable toxic mold "spore counts"

These mold spores vary in significance: procedures that use cultures to identify "viable" spores may omit high levels of non-viable spores which nonetheless remain highly toxic. Methods that rely on culturing have a high risk of identifying a mold which is present but is not the dominant or even the most problematic mold in the building.

For more details see AIRBORNE MOLD COUNT VALIDITY - Mold Spore Counts: are indoor fungal spore counts valid? for further explanation.

Other U.S. & World Government Mold Exposure Standards

For the standards and references below, numbers are spores per cubic meter of air and do not consider individual or viable/non-viable or genera-species specific levels. There is a serious limitation of the standards since the spores of different genera and species vary widely in total size, mass, and toxicity.

The level of airborne particles indoors varies enormously, by orders of magnitude, from moment to moment, making the strict interpretation of any "indoor air mold test" unreliable, as we discuss

at ACCURACY OF AIRBORNE MOLD SPORE COUNTS. -DF

• ASTM International: descriptions of each of the standards below are at our references [25]
  • ASTM D3273 - 12 Standard Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber,
  • ASTM D6008 - 96(2005) Standard Practice for Conducting Environmental Baseline Surveys,
  • ASTM E2018 - 08 Standard Guide for Property Condition Assessments: Baseline Property Condition Assessment Process,
  • ASTM E2418 - 06 Standard Guide for Readily Observable Mold and Conditions Conducive to Mold in Commercial Buildings: Baseline Survey Process,
  • ASTM E2722 - 09 Standard Test Method for Using Seeded-Agar for the Screening Assessment of Antimicrobial Activity in Fabric and Air Filter Media,
  • Note: ASTM has other standards addressing test methods for the ability of various substances or coatings to resist the growth of fungi and other more broad standards addressing site environmental assessments. Some examples of existing standards or standards under development include:
    • ASTM WK32079 - New Test Method for Determination of Mold Growth on Building Products Designed for Exterior Applications using an Environmental chamber and Direct Inoculation.
    • ASTM D4783 - 01(2008) Standard Test Methods for Resistance of Adhesive Preparations in Container to Attack by Bacteria, Yeast, and Fungi
    • ASTM E1527 - 05 Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process (Phase I ESA). [reflects US EPA rules for environmental due diligence as of 11/1/2005, Federal Reference: 40 CFR Part 312]
    • ASTM E 1528-00 Standard Practice for Environmental Site Assessments: Transaction Screen Process (Transaction Screen) [reflects US EPA rules for environmental due diligence as of 11/1/2005, Federal Reference: 40 CFR Part 312]
• Australian Mold Standards:
  
  See this AUSTRALIAN MOULD GUIDELINE AMG-2005-1 (PDF)
• Brazil Mold Standards:
  
  See OCCURRENCE OF AIRBORNE BACTERIA AND FUNGI IN BAYSIDE OFFICES IN RIO DE JANEIRO, BRAZIL, by Brickus, L. S. R., Siqueira, L. F. G., Neto, F. R. D. and Cardoso, J. N., 1998)
• Canadian Mold Standards:
  
  see this Canadian Mould Guidelines Document: HAZARD ALERT ON MOULD IN WORKPLACE, 2000,
  
  Also see:
  • MOULD GUIDELINES FOR THE CANADIAN CONSTRUCTION INDUSTRY [PDF]
  • FUNGAL CONTAMINATION IN BUILDINGS: HEALTH EFFECTS & INVESTIGATION METHOD, [PDF]Health Canada, Minister of Health
  • Canadian Mortgage and Housing Corporation -
    
    see atReferences or Citations Canadian National Toxic Mold Centre, and also
    
    see atReferences or Citations this article: Moldy Houses: Why They Are and Why We Care & Additional Analysis of Wallaceburg Data: the Wallaceburg Health and Housing Studies) CNTMC has adopted
    
    the NEW YORK CITY GUIDELINES ON ASSESSMENT AND REMEDIATION OF FUNGI IN INDOOR ENVIRONMENTS - [PDF] updated in 2008.
  • Facts About Mold. New York City Department of Health. February 2001.
    www.nyc.gov/html/doh/html/epi/epimold.shtml
  • Health Canada: Fungal Contamination in Public Buildings 
    www.hc-sc.gc.ca/ewh-semt/pubs/air/fungal-fongique/index_e.html
  • Fighting Mold. Canada Mortgage and Housing Corporation. 1999
    www.cmhc-schl.gc.ca/en/burema/gesein/abhose/abhose_ce08.cfm
  • After the Flood. Canada Mortgage and Housing Corporation.
    www.cmhc-schl.gc.ca/en/burema/gesein/abhose/abhose_ce07.cfm
  • Moulds: Controlling Exposure is Essential. Construction Safety Association of Ontario.
    www.csao.org/uploadfiles/magazine/vol10no2/moulds.htm
  • The Ontario Ministry of Labour incorporates the New York City Mold guidelines in a Hazard Alert on Mould in Workplace Buildings issued in 2000.
• California Energy Commission See
  • CALIFORNIA MOLD DISCOSURE LAW and the California Department of Health Service / Environmental Health Investigations Branch report on whether it is feasible to adopt permissible exposure limits (PELs) for indoor mold
  • SB 732 TOXIC MOLD PROTECTION ACT of 2001, Implementation Update (August 2006) California enacted its original Toxic Mold Protection Act in 2001. (Ortiz), ratified October 7, 2001.
  • California Assembly Bill 284 (Jackson), ratified October 7, 2001.
  • California Department of Health Services (Ca-DHS) Fact Sheet "Mold in My Home, What Do I Do", 2001.
• European Union mold exposure standards: for apartments the E.U. uses these mold level designations
  • Indoor mold spore counts of < 50/m³ very low
  • Indoor mold spore counts of < 200/m³ low
  • Indoor mold spore counts of < 1000/m³ medium
  • Indoor mold spore counts of < 10000/m³ high
  • Indoor mold spore counts of > 10000/m³ very high -- BUILDING BIOLOGY EVALUATION GUIDELINES [PDF]
  • Former building biology reference values for molds, SBM-1998 through SBM-2003 (using YM Baubiologie Agar at a culture temperature of 20-24 °C, colony forming units CFU): in the air < 200 no, 200-500 slight, 500-1000 strong, > 1000/m³ extreme anomaly (values refer for indoor air when outdoor reference levels are relatively low, below 500/m³); on surfaces: < 20 no, 20-50 slight, 50-100 strong, > 100/dm² extreme anomaly (values refer to surfaces that are subject to common and regular cleaning practices)
  • WHO: World Health Organization, pathogenic and toxigenic fungi are not acceptable in indoor air;
    
    from 50/m³ of a single fungal species, the source(s) needs to be identified; a mixture of common fungi typical for a given location (e.g. cladosporium) can be tolerated up to 500/m³.
    
    Senkpiel/Ohgke: Indoor concen-trations that are over 100/m³ above the outdoor air indicate a problem.
    
    EU statistics for apartments: < 50/m³ very low, < 200/m³ low, < 1000/m³ medium, < 10000/m³ high, > 10000/m³ very high. See 'Schimmelpilz-Leitfaden' by Environment Agency (Germany) for assessment details.
• France mold exposure standards: see BUILDING BIOLOGY EVALUATION GUIDELINE [PDF]
• Germany mold exposure standards: see BUILDING BIOLOGY EVALUATION GUIDELINE [PDF]
• Massachussetts mold legislation: Massachusetts, Michigan, New Jersey, New Mexico and New York, either have or are considering similar or modified mold protection acts similar to California's Toxic Mold Protection Act.
• Montana and other U.S. States mold disclosure legislation: requires building seller disclosure of mold during real estate transactions: Louisiana, Michigan, Montana, Nevada, New York, Oregon, Texas, & Washington either have mold disclosure laws or mold disclosure bills in committe. A California disclosure bill failed to pass in 2002.
• New York City Department of Health Mold Severity Levels:
  • NEW YORK CITY GUIDELINES ON ASSESSMENT AND REMEDIATION OF FUNGI IN INDOOR ENVIRONMENTS -[PDF] updated in 2008. The New York City Guidelines on Assessment and Remediation of Fungi in Indoor Environments, 2000, issued by the New York City Department of Health, have are been widely accepted and quoted by public health departments in various U.S. states, Canadian povinces, and other regulatory agencies in other countries. - New York City Department of Health, Bureau of Environmental & Occupational Disease Epidemiology "Guidelines On Assessment & Remediation Of Fungi In Indoor Environments".
  • The Ontario Ministry of Labour incorporates these guidelines in a Hazard Alert on Mould in Workplace Buildings issued in 2000.
• USA Associations - General:
  • American Conference of Governmental Industrial Hygienists (ACGIH) "Bioaerosols: Assessment and Control" Book, 1999
  • ASTM & ASTM International - see ASTM MOLD STANDARDS above in this document
  • Institute of Inspection, Cleaning & Restoration Certification (IICRC) Document S500
• U.S. CDC mold standards - and other molds, Questions and Answers on Stachybotrys Chartarum and Other Molds. Centers for Disease Control and Prevention, National Center for Environmental Health. March 9, 2000.
• U.S. EPA mold exposure standards
  • MOLD REMEDIATION IN SCHOOLS AND COMMERCIAL BUILDINGS [PDF] Environmental Protection Agency (EPA) "Mold Remediation in Schools and Commercial Buildings", EPA 402-K-01-001, March 2001, updated September 2008
  • Environmental Protection Agency (EPA "IAQ Tools for Schools".
• U.S. OSHA  mold exposure standards -
  
  see OSHA's POLICIES REGARDING MOLD [PDF]
  
  and OSHA's BRIEF GUIDE to MOLD in the WORKPLACE [PDF]
• WHO - World Health Organization mold exposure standards- see World Health Organization Mold Bulletin. World Health Organization mold exposure guidelines specify that pathogenic and toxigenic fungi are not acceptable in indoor air as follows:
  • Mold spore counts of over 50/m³: for a single mold species, identify the source of mold
  • Mold spore count sup to 500/m³: a mixture of common fungi typical for a given location is acceptable - an example would be the most common mold genera found outdoors, Cladosporium sp.
  • According to Senkpiel/Ohgke: Indoor concentrations that are over 100/m³ above the outdoor air indicate a problem (we would argue that this standard is inappropriately tight) -- 'Schimmelpilz-Leitfaden', German Environmental Protection Agency
  • Source: Building Biology Evaluation Guidelines for the E.U.
  • World Health Organization (WHO) "Health Guidelines on Biological Agents in the Indoor Environment" (DRAFT as of August 4, 2000)

Note: Previous data provided at this web article had been obtained from a presentation by J.R. Tucker, EMS-sales, who presented data at the NC/SC Environmental Information Association 2005 Conference, Myrtle Beach, SC citing mold exposure standards from Brazil, mold exposure standards for Czechoslovakia, Mold exposure guidelines for Finland, Mold exposure standards set by the Nordic Council, mold standards cited by the World Health Organization WHO, and mold exposure standards for the Netherlands and lastly, mold exposure standards for Poland.

Those figures were quoted in this article from the material provided at that conference. Mold exposure standard numbers were expressed spores per cubic meter of air and did not consider individual or viable/non-viable or genera-species specific levels. We have removed those data points at the request of Dr. Robert Brandys who informed us that he was and remains the original author.

The Toxic Effects of Mycotoxins on Humans, Sheep, & Possibly on Pets

Mycotoxins are produced by some common molds found in buildings, including Aspergillus, Penicillium, Fusarium, Stachybotrys, and even Alternaria. Common classification groups of mycotoxins include aflatoxins, fumonisins, trichothecens, and ergot alkaloids. Arora has pointed out that the following conditions are necessary for mycotoxins to affect humans:

1. The right environment must be present for mycotoxin-producing molds to actually produce mycotoxins.
   
   I have pointed out elsewhere that a given mold may produce or not product mycotoxins as a function of varying environmental conditions including the presence or absence of particular nutrients available to the mold -- i.e. it may depend on just what material is supporting the mold growth, not simply on the presence of mold and moisture.
   
   For building occupants whose physician has tested and confirmed high trichothecene levels, the trichothecene exposure can often be traced to some species of Aspergillus or Penicillum but in a significant percentage of cases we have investigated, trichothecene levels correlated with the presence of a significant Stachybotrys chartarum mold reservoir. S chartarum is not normally airborne but becomes so during demolition;
2. The mycotoxin(s) must have a pathway from the source to a susceptible person.
   
   The pathway may be direct contact with moldy material, inhalation of airborne spores or fungal fragments or of contaminated building materials. Important in understanding this pathway and the significance of "moldy odors" which we ascribe to volatile organic compounds given off by some molds under some conditions, mycotoxins are not volatile.
   
   Therefore, as Arora explains, airborne mycotoxin transmission has to be by inhalation of aerosolized mold or mold-contaminated materials. We point out elsewhere that the particle levels in air in a building vary widely over time for many reasons.
   
   However it should be no surprise to find airborne mold or mold-contaminated debris in a moldy building, particularly if demolition or improper "mold remediation" is going on.
3. The person has to absorb a toxic dose of the mycotoxin(s) over a sufficiently short time period. "
   
   Very little is known about what constitutes a toxic dose for humans -- see Stachybotrys chartarum mycotoxin discussion below.

Human Health Complaints on Exposure to Problematic Mold, possibly including Mycotoxins

Given even these stringent criteria, field investigations of moldy buildings that we have conducted from 1986 to present, included both human building occupants and in some cases pets who appeared exhibit complaints or symptoms consistent with mycotoxin exposure.

Some of these clients and their physicians confirmed that exposure by appropriate medical tests.

Sheep Circling Disease and Toxic Mold Exposure

A fellow aerobiologist who also has experience raising sheep, Larry Syzdek (PAAA member) informed us of a mold-related illness well known to occur in sheep which Syzdek explained has occurred in his experience in sheep exposed to moldy straw, called in lay terms, "sheep circling disease"

(Listeriosis, however Listeria moncytogenes is the specific bacterium - not a mold - known to cause listeriosis, a disease which can affect both other animals and also humans, particularly pregnant women who are 20 times more likely than other healthy adults to get listeriosis).

The author of this web article, (Friedman) has described field observations of dogs appearing to exhibit strange behavior (running in circles, falling down, disorientation, and occasional uncharacteristic aggressive behavior, and in one case, fatal internal bleeding after severe exposure to S. chartarum during a building demolition.

These animals were pets of clients whose homes were severely mold-contaminated.

With Syzdek, we have speculated on the possibility that other animals than sheep may be similar affected by exposure to some indoor molds and may be exhibiting behavior similar to that caused by Listgeriosis though the etiology of this disease is suspected to be different.

At MOLD RELATED ILLNESS GUIDE or in the FAQs section of that article we include a 2014 report from a Salem Oregon family who describe drunken behaviour of dogs after the dogs spend time outdoors.

These hypothetical remarks presented here intend to solicit additional field reports and data, possibly in support of future controlled studies. Readers should not assume that we have drawn conclusions from the suggestive anecdotal data currently at hand.

Contamination levels of specific allergenic or toxic mold spores

Some species specific acceptable levels have been addressed and vary considerably by species, environmental conditions, and proponent.

REFERENCE:A number of resources cited here are reviewed more carefully in "Comparisons of seasonal fungal prevalence in indoor and outdoor air and in house dusts of dwellings in one Northeast American County," Ping Ren, Thomas M. Jaunkun and Brian P. Leaderer, Division of Environmental Health Sciences, Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven Ct. and appearing in the Journal of Exposure Analysis and Environmental Epidemiology (1999) 9, 560-568. http://www.stockton-press.co.uk

See REFERNCES for important additional information such as mold testing, cleanup and mold remediation guideline resources.

Stachybotrys chartarum in air

According to A.S. Arora: Stachybotrys chartarum strain s72 contains 1.0x10-4 nanograms of satratoxin H per spore. 10 billion spores of s72 S. chartarum must be present in a single cubic meter of air to produce one milligram of satratoxin H per meter of air.

Dr. Arora continues: "... it was calculated that a no-effect dose [in rats] corresponds to a 24-hour exposure to 3 billion spores per cubic meter of air for an infant [human], 9.5 billions spores per meter for school-age children, and 22 billion spores per cubic meter for adults."

Dr. Arora did not expand his discussion to address any potential cumulative toxicity of longer term exposure to lower levels of mycotoxins in buildings.

This "toxic black mold," Stachybotrys chartarum, infamous thanks to media attention, is not designed for airborne transmission, being large and sticky. The Stachybotrys family of molds appear to have evolved to be spread by sticking to the cow's foot as it walked through moldy straw.

Indeed we often find S. chartarum mold spores present in air samples when a dense colony of such mold is being mechanically disturbed, such as during demolition.

But we have never seen it in air anywhere close to the levels cited as the "no-effect dose." We believe that we've been barking up the wrong mold-tree, and that one would be smarter to look in buildings for the Penicillium and Aspergillus families which spread throughout a building easily by airborne transmission

• Content of this section paraphrased and others quoted from a guest column, "Understanding the Health Effects of Mold," by Dr. Ajit S. Arora, MD, PhD, appearing in AIHA's magazine "The Synergist," September 2003, in the AIH Diplomate section, Pages vi-vii. Dr. Arora is a forensic medical examiner and medical toxicologist in Los Angeles. See partheniamedical.com.

Penicillium sp.

"Clean" residential buildings are typically 230/m3 +/- 630.

Buildings with evidence of flooding are typically much higher: 2200/m3 and

Mold-damaged buildings are typically extremely high in comparison: 36,000/m3.

We usually find only trace levels of Penicillium/Aspergillus indoors in residential buildings and offices, so counts even close to the "clean" level may make further investigation a reasonable course of action, particularly where the building houses occupants have complaints possibly due to mold, or occupants who may be at extra risk.

Aspergillus sp.

Holmberg (1987) associated Aspergillus spore levels over 50 CFU / cubic meter with sick building syndrome.

We comment elsewhere that depending on culturing mold in buildings is unreliable since toxic or allergenic particles may be present but may be of a species or genera which either does not grow on a culture medium, or which is overgrown by something else on the medium.

Further, relying on settlement plates to culture mold produces quantitatively skewed results since different particles settle out of air at different rates, confounding an estimate of their numbers. Anderson™ multi-stage samplers which develop culturable samples attempt to overcome the particle size problem.(C)Trap DJ Friedman

Aspergillus sp. may be the most common and serious airborne mold problems in buildings:

Opinion: from the author (DJ Friedman) based on extensive field investigations and laboratory work, we suspect that several species of Aspergillus are probably the most common and widespread problem mold found indoors in buildings.

These spores are small, easily airborne, grow on a variety of surface materials, and move readily throughout a building almost like a gas (due to their small size) riding on building convection currents and remaining airborne for long periods of time.

...

Aspergillus Limits / & Testing Standards for Cannabis

This private email discussion in 2023 is reported here to invite reader and expert comments & suggestions about the question raised by the reader.

Acceptable Limits of Aspergillus species: Aflavus, A niger, A terrus and A fumagatis on Inhaled Cannabis (Marijuana)

I found your site very helpful.  I'm wondering if you have any data / guidance based on your background on acceptable limits of aspergillus (flavus, niger, terrus and fumagatis) on an inhaled product like cannabis.  Most states have a no detect limit but I wanted to know if there is research or data to back up the limit.

Our firm is a method developer of qPCR and NGS for pathogens in the cannabis and hemp sector.  We wanted to support the regulators with additional data on why aspergillus testing is important. 

- Anonymous by private email 2023/06/23

Moderator Reply: OPINION - Aspergillus testing is important but may be dangerously insufficient

Thanks for an interesting question.

I will do some research but off-hand I don't have an allowable mold standard for cannabis.

In my opinion (based on field and lab work) is that it may be reasonable to use one or a few molds as "markers" for mold contamination on mold friendly material such as cannabis, but one wants to be very careful to avoid claiming that just because mold A is not found that a product is mold free.

I'm also concerned that the method used to detect the presence of mold or MVOCs or other harmful substances produced by mold on cannabis may be seriously deficient.

Watch out: some time ago I performed forensic analysis on imported teas for a U.S. importer/vendor who was getting mold complaints.

We identified several kinds of mold on the tea, including some species of Aspergillus.

There will almost always be multiple mold genera/species present. Focusing on just one is risky. For example, downy or powdery mildew may be common on most plant leaves and some stems.

Even at low levels the mold was causing reactions in some customers, varying by level and nature of exposure and of course individual sensitivity and vulnerability.

Watch out for what methods you're using to "identify" mold in cannabis. At https://inspectapedia.com/mold/Mold_Culture_Test_Method.php we described using culture media to grow some molds found in tea, but I warn that as much as 90% of molds won't grow in any culture media whatsoever. So if we're screening a plant material for mold by using cultures, we're 90% wrong the moment we start our test.

In my OPINION states setting a "not detected" limit for mold in cannabis for sale to the public are being smart.

There may be more than one hazard sort if cannabis is moldy:

1. exposure to inhaled harmful molds or MVOCs from the product while stored and handled. This is the more-straightforward concern.

2. exposure to mvocs and unknown levels of mold and mold combustion products during smoking. Before having any actual authoritative data whatsoever, my instinct says that this is a very risky situation since a user is inhaling smoke that may contain burned, partially-burned, and even un-burned mold spores and mvocs, often deeply into the lungs.

3. Let's both see what more research we can find and report back to one another.

Watch out when reading research papers however.

It may seem natural to research standards and effects regarding mold in tobacco. But while tobacco blue mold is a serious annual concern for tobacco growers in the U.S. and Canada, cured tobacco may respond to mold quite differently from cannabis. I'm doubtful that the mold friendliness of the two plants will be found to be equal.

Research & Standards for Mold in Cannabis

Note that typical testing limits for mold in cannabis set a limit of "Absent" in a "Present/Absent" type test.

• ASTM Standard Practice for Determination of Water Activity (aw) in Cannabis Flower (D8196)
• ASTM Standard Specification for Maintaining Acceptable Water Activity (aw) Range (0.55 to 0.65) for Dry Cannabis Flower (D8197)
• CA, MEDICINAL AND ADULT-USE COMMERCIAL CANNABIS REGULATIONS CALIFORNIA CODE OF REGULATIONS TITLE 4 [PDF] California Department of Cannabis Control, Division 19. Department of Cannabis Control, retrieverd 2023/06/26 original source: cannabis.ca.gov/wp-content/uploads/sites/2/2021/10/DCC-Cannabis-Regulations-Sept.-2021.pdf
• Cannibis Testing Regulations by State - from these private providers (as of 2023/067/26)
  
  medicinalgenomics.com/resource/cannabis-microbial-testing-regulations-by-state/
  
  pathogendx.com/state-cannabis-microbial-testing-regulations/
• Freeman, Kalev, M. McHenry, W. Cats-Baril, and T. Grace. CANNABIS TESTING FOR PUBLIC SAFETY-BEST PRACTICES FOR VERMONT ANALYTICAL LABORATORIES [PDF]  PhytoScience Institute (2016).
  Excerpts:
  
  This paper provides a summary of the best practices for analytical laboratories that perform testing of Cannabis and Cannabis-derived products intended for human consumption. Specifically, we address the following questions for regulators and policy makers interested in ensuring safety as the Vermont Cannabis industry evolves: How should Cannabis products be tested for public safety? How should the testing laboratories be regulated and accredited?
  
  What will it cost to do the recommended testing? In the absence of guidance from the United States Department of Agriculture (USDA), the Food and Drug Administration (FDA), or the Environmental Protection Agency (EPA), regulatory agencies in states allowing retail sales of Cannabis and Cannabis-derived products must decide whether safety testing will be required of these products.
  
  States also must decide how to inspect and certify the laboratories that will perform the necessary analytical testing. We provide specific recommendations that can serve as a roadmap for policy makers seeking direction in the uncharted territory of Cannabis in public health and safety considerations.
  
  This information should be widely generalizable to governmental regulatory bodies and private sector interests throughout the United States who are confronted with similar challenges as those faced in Vermont.

• Marcoux, Rita, Lauren Holmes, and F. Randy Vogenberg. "Regulatory and legislative disparities with cannabis present challenges to P&T committees and health care providers." Pharmacy and Therapeutics 44, no. 5 (2019): 290.
• McKernan, Kevin, Jessica Spangler, Yvonne Helbert, Ryan C. Lynch, Adrian Devitt-Lee, Lei Zhang, Wendell Orphe et al. "Metagenomic analysis of medicinal Cannabis samples; pathogenic bacteria, toxigenic fungi, and beneficial microbes grow in culture-based yeast and mold tests." F1000Research 5, no. 2471 (2016): 2471.
• MI, SAMPLING AND TESTING TECHNICAL GUIDANCE FOR MARIJUANA PRODUCTS [PDF] (2022) Michigan State Government, CRA, retrieved 2023/06/26, original source: michigan.gov/cra/-/media/Project/Websites/cra/bulletin/5Technical/Sampling_and_Testing-_Technical_Guidance_for_Marijuana_Products_694124_7.pdf
  
  Excerpt:
  The Cannabis Regulatory Agency (CRA) is committed to evidence-based decisionmaking when implementing technical guidance for licensed laboratories. As research into marijuana use, safety, and testing advances, this guide may be revised and updated to reflect these changes where appropriate. Upon licensing of a safety compliance facility/marihuana safety compliance facility, licensees must comply with all applicable statutes, administrative rules.
• NYS, REQUIRED TESTING OF EACH LOT OF ADULT USE CANNABIS AND MEDICAL CANNIBIS PRODUCT [PDF] New York State Office of Cannabis Management, retrieved 2023/06/26, original source: https://cannabis.ny.gov/system/files/documents/2023/01/ocm-testing-limits.pdf
  Excerpt:
  
  This document lists the permitted analytes and sets testing limits for contaminants as directed in 9 New York Codes, Rules and Regulations (NYCRR) Part 130 and Cannabis Law.
  
  Testing for each contaminant is required for all final adult- use and medical cannabis product types unless expressly noted.
  
  Additional analytes may be added. These limits may be modified where it is in the best interest of public health and safety
• Seltenrich, Nate. CANNABIS CONTAMINANTS: REGULATING SOLVENTS, MICROBES, AND METALS IN LEGAL WEED [PDF] (2019): 082001. US NIH, Envrionmental Health Perspectives, EHP, retreived 2023/06.26 original source: https://ehp.niehs.nih.gov/doi/full/10.1289/EHP5785
  
  Abstract excerpt:
  
  Policing the quality and safety of cannabis products is far from straightforward.
  
  Such products come in many forms and infusions that can be inhaled or ingested, including traditional cured “flower” for smoking or vaporizing; a range of concentrates, oils, and tinctures; and all manner of foods and drinks.
  
  Further complicating the matter is the plant’s dual role as both a recreational and a medical drug used to treat a wide range of conditions.
  
  Cannabis users include not only healthy adults but also more sensitive or vulnerable members of the population, including children and patients with cancer or HIV.
• Yaghmaee, Pareastoo, PhD, TOTAL YEAST & MOLD COUNT: WHAT CULTIVATORS & BUSINESS OWNERS NEED TO KNOW [PDF] (2017), Cannabis Industry Journal, retrieved 6/26/2023, original source: cannabisindustryjournal.com/feature_article/total-yeast-mold-count-what-cultivators-business-owners-need-to-know/
  
  Excerpt: Dec 12, 2017 — At the time of writing this article, the acceptable limit for TYMC in cannabis plant material in Colorado, Nevada and Canada is ≤10,000 CFU/g.

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2020-07-28 by Vickie

Our home was reported to have a mold count of 12,000 m3. It was established that the mold was NOT black mold. Residing under the sink due to a leaky garbage disposal. We've cleaned with the product Kilz.Should we do anything more? Thank you

On 2020-07-26 - by (mod) -

Chaetomium is a "water indicator" mold = telling us that there was a leak; it is almost never going to be the only mold genera/species present.

Much more important than identifying specific species is to find the extent of moldy material - and remove it.

If you had less than 30 sq ft of contiguous moldy material then most standards would not call for professional mold remediation.

Air testing is unreliable as a building screen for mold, particularly when the results are negative.

On 2020-07-26 by Conrad Torres

I’m a landlord that had a leak at the top of my tenants front door. The leak happened during the rainy season and I decided to get a new door.
When the contractor went to replace the door there was visible mold behind the door casing and behind drywall.
I had a test done and it came back finding Chaetomium on door frame but no where else.
Air samples were also done and the levels of mold inside were well below the outdoor air sample. No chaetomium was found in the air sample.

My tenants are claiming they had to spend 30 days in the hospital from mold exposure.

I don’t see how that could be, if the chaetomium isn’t a toxic mold and since it wasn’t found in the air?

I thought you actually have to breath in or ingest mold in order to get sick?

On 2020-06-24 - by (mod) -

That suggests there's a mold reservoir nearby the measurement point and that the situation merits further investigation.

Nothing in an "air test" for mold is sufficiently diagnostic so now you probably need to do what was needed (pardon me) in the first place: hire an inspector who actually inspects the home, takes a history, examines the exterior and interior, finds the mold reservoir, defines the scope of cleanup needed, and explains the cause and thus the cure for the mold contamination. The project size can't be estimated from your report.

On 2020-06-24 by Peg Keeley

Mold report for a full basement that has a sump pump but is dry and has not flooded in several years showed the following:
Chaetomium raw count:7 spores/m3: 47 % total: <1 penecillium/aspergillus raw count: 703 spores/m3: 4710 total: 96%

there was an outdoor control done that showed nothing and an upstairs (main part of house) that showed nothing
there was no report of examination that would reveal an actual physical description of the mold.

is this a problem that we need to deal with and how?>

On 2020-06-20 - by (mod) -

Connie

Those are not high numbers and are consistent with testing immediately after a cleanup where the building has not been sufficiently ventilated.

If the counts persist then there is probably a persistent source of mold that was not found and thus not removed.

Watch out: air tests for mold are fundamentally inaccurate and can vary by 4 orders of magnitude depending on small changes in site conditions.

An airborne mold spore count of 320 /m3 might actually be 0.1 spores per cubic meter, or it might be 12,000 or more.

see AIRBORNE MOLD COUNT VALIDITY https://inspectapedia.com/mold/Mold_Count_Accuracy.php

On 2020-06-20 - by (mod) -

Connie

Those are not high numbers and are consistent with testing immediately after a cleanup where the building has not been sufficiently ventilated.

If the counts persist then there is probably a persistent source of mold that was not found and thus not removed.

Watch out: air tests for mold are fundamentally inaccurate and can vary by 4 orders of magnitude depending on small changes in site conditions.

An airborne mold spore count of 320 /m3 might actually be 0.1 spores per cubic meter, or it might be 12,000 or more.

On 2020-06-20 by Connie

Mold air a Quality Survey after remodeling a small subterranean unit that previously had water damage had the following:

asp/pen 320 /m3 ; basisiospores - 80 ; cladosporium 760 ; Epicoccum 13 ; Smuts/Myxomycetes 80 ; stacybotrys/ memnoniella 53 and total counts of 970, 690, and 200 and 480 in each room. Are these high levels after remediation has occurred?

On 2020-03-09 by kris

I received an air quality test report back indicating that I have a high level of chaetomium in my master bedroom and kids room; level being at 200 spores/m3 and 40 spores/m3 along with addiction stating myxomycetes at 1960 spores/m3 in one room and 280 spores/m3 in another. what does this mean and should I be concerned about our health?

On 2020-01-04 - by (mod) -

In my view even comparing spore counts with outdoor count is questionable since there are so many species of both Penicillium and Aspergillus that we have absolutely no assurance that the outdoor Aspergillus count is even the same species - it could be a completely different person.

And no air test for mold is, by itself, a reliable building screen for mold. I find huge variation depending on just when where and how a "test" is conducted.

What you can say is that the indoor Pen/Asp count suggests that there is probably a mold colony somewhere to be found and removed and its cause fixed.

On 2019-12-29 by Anonymous

I just received a spore trap report about my house, the renter says she is having health issues since she moved into the house 2 months ago.

There was a bit of water leakage right around the time she moved in which affected the carpet and a countertop but there is also an outside wall in a shop that has a crack in the foundation and it has been leaking into that shop.

This shop is not part of the living area and is divided by a wall not affected by the leak. The numbers in the test are Penicillum/Aspergillus types being the very highest with raw ct: 146, count/m3: 1900 and DL/m3: 13. Are those numbers a concern? The lab will not interpret them unless I do an outside comparison test for more money.

On 2019-12-04 - by (mod) -

Air tests as a building screen for mold are not, used alone, reliable as there is great variability in test results.

Your test, if I understand your data, is based on detecting 1 mold spore. If so, by itself it has no meaning at all. Surely the people you paid for this owe you an explanation. What did your onsite expert say?

On 2019-12-03 by Tyler

Used self test airborne kit and sent to lab on a townhome I lease. Results showed 1 part chaetomium/50 spores per m3. Outside control shows 0 for this spore. All other readings fine. Is this level to be concerned about? I removed some stained carpet by an entryway door, which I thought might be the source.

On 2019-10-31 - by (mod) -

In the live links at ARTICLE INDEX at the end of this page see

AIRBORNE MOLD COUNT NUMBER GUIDE

And

MOLD EXPOSURE RISK LEVELS

On 2019-10-31 by Hubbard

Levels are at 5 on a 1-5 scale 1 being lowest, the name is aspergilus-pinicillium. Is inside dwelling readings, with fruiting bodies present. Are we at risk

On 2019-10-16 - by (mod) -

Philip

"Numbers" alone as mold "counts" are difficult to interpret except in very general terms like "looks high" or "looks like a mold problem" because beyond that we don't have a shred of information about the building, its history, what problems were present, exactly what was done to correct them, and because air tests for mold have stunning variability - at least 4 orders of magnitude depending on small details of just how the test was performed.

Just having someone walk through a room during such a test can multiply the "airborne spores per cubic meter" by a factor of 10.

My opinion is that the person performing the test has an obligation to help you understand its meaning as that person, unlike me, has inspected the building and knows its history.

Beyond that and glancing at your incomplete report one can see that outdoor airborne spore counts (a very rough control number) were higher than indoor counts and that the "raw" or absolute indoor spore count numbers were indeed a bit "high" - perhaps consistent with leftover contamination after a mold contamination cleanup or more-likely in the case you describe, a remediation project that has not actually found and removed a mold reservoir.

Watch out: however, because "bleaching" or "killing" mold is a fundamentally mistaken approach to indoor mold contamination remediation. The proper objectives are

1. REMOVE the mold either by cleaning hard cleanable surfaces or removing mold contaminated materials (like drywall, wall to wall carpet, insulation) that cannot be effectively cleaned

2. CORRECT the cause of the mold contamination

The idea of "killing" mold with bleach is also a mistake because not only is it a too-superficial approach for many mold-contaminated mateirals, but also "dead" mold spores - spores that can no longer propagate or grow - may nonetheless remain toxic or allergenic.

See AIRBORNE MOLD COUNT NUMBER GUIDE - home - at inspectapedia.com/mold/Airborne_Mold_Count_Number_Guide.php

and

See MOLD CLEANUP, BLEACH inspectapedia.com/mold/Bleach_Mold_Contamination.php

On 2019-10-16 by Philip Patrick Brazil

The school I work for just had a test done in a classroom. Our original reading was high. We washed everything with bleach and our reading came back lower but still too high. Can anyone tell me what these numbers mean?

Question: meaning of air test mold counts

(Mar 12, 2016) Concerned Mother said:
We recently had an air quality test completed throughout the house, due to illness in the family. These came back as being high in the lower level (LL), main level (ML) and upper level (UL).

Are these levels high enough to cause a true concern?

Should the basement be gutted or cleaned and gutted where the mold is seen at? What should be done on the main and upper levels of the house?
I appreciate your guidance!
Thank you

Aspergillus/Penicillium LL 6667 ML 293 UL 373

Chaetomium LL 33 ML 13 UL 13

Stachybotrys / Mennoniella LL 133

(Sept 25, 2016) Cindy said:
Had an air test done and stachybotus came back as 2 on only room in house. Penicillin and Aspergillus came back zero.

Is there a reason to worry or do further testing? Thanks great info on this sight.

Reply:

Concerned and Cindy:

Regrettably the test results alone, without a competent and thorough building inspection for mold reservoirs, both visible and if appropriate, hidden, for building leak history, for occupant vulnerability and IAQ complaints, is nearly worthless - certainly it is not diagnostic.

I see variation from 1 to 4 orders of magnitude in airborne particle counts depending on how a test was conducted so an accurate mold level that produced an airborne spore "count" of 13 might be anywhere from 1.3 spores/cubic meter of air to 4000 times that amount. Sorry I can't say what should be done based on so little information.

My best advice is to ask for your mold test money back since the person who was in your home, where your money and health are at risk, has apparently thrown a test result over the wall (figuratively) without answering even the most basic questions.

Question: cleanup after bringing dusty books into the home

(Apr 30, 2016) Sorry Susan said:
I brought some dusty books into my home and they were sitting on carpet. What is the most practical thing to do now? Is vacuuming and airing out the room a bad idea? Vacuuming the carpet? There is not a high level of humidity and no visible signs of mold.

I meant shampooing the carpet after vacuuming and airing?

Reply:

Normal housecleaning and vacuuming sound sufficient to me.

Comment:

(Aug 26, 2016) Anna levis said:

Why mold cause sever health problems just because of the people not take any action when they found mold in their house and after that the mold increases in growth and cause severe health issues to homeowners.

They spend their day in that environment which is highly affected with the Toxic black mold which can also harmful to your health and cause a permanent damage.

Homeowners never realize the affter effects of that black mold until they practically go through it. Toxic black mold cause problems such as mental disability, damaging internal organs, and sometimes a purpose of death. You can just have a quick checklist to remove Black mold without killing the environment as i have found both of the articles helpful for me

Reply:

Please search InspectApedia.com for MOLD KILLING GUIDE to read about the problem you discuss.

Question: renting a moldy home

(Oct 17, 2016) Casey Lee said:
Aspergillus Penicillium in my bathroom is at 89% and the count is at 800m3 and the living room is at a count of 2300. I have been having bad breathing problems rashes eye irritation as well as loosing hair and just plan wore out all the time.

I have been expierencing this for a year now and my apartment won't do anything about it even when I found the leak behind my toilet inside the walls that had rotted out all the wood and caused serious damage to building and observed them cover it up without cleaning or replacing wood!

And leaving the wall open for weeks for me and my 10 year old daughter to get even worse, even our dogs started itching and loosing they're coats. 😞 I don't know what else to do. I hired a mold inspector at $750 (out of my rent here! But the management don't know yet) and the results basically are saying there's a lot of different moods but no dominating ones. It hasn't been dissmissed but they want ta recheck at a later date. I can't keep living like this

Reply:

Advice for your situation is at RENTERS & TENANTS ADVICE for UNSAFE or UNHEALTHY HOME

...

Continue reading at MOLD TEST vs. PROBLEM DIAGNOSIS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see MOLD EXPOSURE STANDARDS FAQs - questions & answers about various standards for acceptable exposure levels for mold in buildings

Or see these

Mold Standards Articles

• MOLD EXPOSURE STANDARDS - home
• ASTM Mold Standards
• AUSTRALIAN Mould Guidelines [PDF]
• CALIFORNIA Mold Disclosure Law
• MOULD STANDARDS CANADA
• EUROPEAN Union Mold Standards
• NEW YORK CITY Mold Guidelines [PDF]
• OSHA Guide to Workplace Mold
• WHO WORLD HEALTH ORGANIZATION Mold Bulletin

Or see these

Recommended Articles

• ACCURACY OF AIR TESTS for MOLD - home
• ACCURACY of MOLD TESTS - all types of mold tests
• AIRBORNE MOLD SPORE COUNT GUIDE - home
• AIRBORNE PARTICLE LEVELS vs IAQ - home
• AIRBORNE MOLD COUNT VALIDITY
• AIRBORNE PARTICLE COUNT VARIATION CAUSES
• AIRBORNE PARTICLE COUNT VARIATION EXTENT
• AIRBORNE PARTICLE COUNTS in DUCTWORK
• AIRBORNE PARTICLE COUNTS vs SAMPLER HEIGHT
• AIRBORNE PARTICLE COUNTS vs WINDOWS, DOORS
• ALLERGENS in BUILDINGS, RECOGNIZING
• MOLD CULTURE TEST KIT VALIDITY
• MOLD EXPOSURE RISK LEVELS
• MOLD EXPOSURE STANDARDS - home
• MOLD INVESTIGATION REPORTS
• MOLD LEVEL REPORTING
• MOLD TESTING METHOD VALIDITY
• MOLD TESTING & SAMPLING MISTAKES
• USES of AIRBORNE PARTICLE SAMPLING
• VISUAL INSPECTION & HISTORY of MOLD

Suggested citation for this web page

MOLD EXPOSURE STANDARDS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to MOLD CONTAMINATION & REMEDIATION

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