Molds are commonly found in buildings and homes. They grow in damp or wet places such as around leaks in roofs, windows, or pipes, or where there has been flooding. Molds grow well on organic materials such as paper products, cardboard, ceiling tiles, and wood products. Mold can also grow in dust, paints, wallpaper, insulation, drywall, carpet, fabric, and upholstery.

The most common indoor molds include Cladosporium, Penicillium, and Aspergillus.

Fungi are present in virtually all environments and affect us in many ways. Spores of many fungal species have been documented as important causes of allergy when inhaled people who are susceptible individuals. Experts estimate that 20% of the human population is susceptible to fungal spore allergy.

How to and why Trap Airborne Fungal Spores

Airborne fungal spores can be trapped for either culturable or non-culturable analysis. They are commonly trapped from the air to evaluate the potential human exposure to fungal allergens. Fungal spore trapping is also commonly used in crop disease outbreak predictions so that suitable control measures can be undertaken in advance to avoid crop losses. For human exposure, non-culturable methods would be preferred. However for crop disease outbreaks or product damage, culturable methods would be preferred.

Fungi are in Buildings and Homes

Fungi are very commonly found in indoor environments. They grow in buildings with a lot of moisture due to leaks in roofs, windows, or pipes, or flooding. Fungi grow well on organic materials such as paper products, cardboard, ceiling tiles, and wood products. Fungi can also grow in dust, paints, wallpaper, insulation, drywall, carpet, fabric, and upholstery. The most common indoor Fungi are Cladosporium, Penicillium, and Aspergillus.

Identification and Enumeration of Airborne Fungal Spores

Identification and enumeration of airborne fungal spores are highly specialized skills. The spores come in a wide range of types and sizes, all are microscopic with some as small as two micrometres in size. Many fungi produce only small amounts of spores which rarely get airborne in quantity. However, some species are very prolific and widespread, producing high concentrations of spores which are readily dispersed into the air. Identification of airborne fungal spores is based on spore characteristics such as the size, color, shape, texture and number of cells. 

Mold & Bacteria Consulting Laboratories offers a course on how to accurately identify and enumerate a wide variety of airborne spore types and differentiate them from other biological and non-biological particles. These skills will be useful for those intending to analyze, monitor, or study indoor or outdoor airborne fungal spore concentrations. The course is also useful to environmental consulting firms that would like to set up in-house fungal identification laboratories.

Try our Mold Spore Quiz. It’s Fun!!

Some of these molds such as Stachybotrys, Aspergillus and Penicillium are associated with adverse health effects. Others like Alternaria and Cladosporium are well known allergens that trigger allergic reactions to sensitized individuals.

BUT, not all black molds that occur indoors are hazardous. Also, some dangerous molds are not black.

For $54.99 (Canadian dollar) per sample, you may submit a mold sample to determine whether the mold present is hazardous or only a cosmetic concern. A tape-lift mold sample is the most inexpensive test, and from it, Mold & Bacteria Consulting Laboratories can give you information and guidance on what to do next. It is an easy way to determine if the mold is toxic and if it will require more intensive investigation and remediation. Cleaning hazardous mold requires special protection.

How Do You Take Mold Samples?

If you hire a professional mold inspector to come to your home, they’ll take samples and send these samples to a third-party laboratory to find out the kinds of mold present in your home. What if you can collect the samples yourself and send them directly to the same lab? It would not only save you money but also give you an opportunity to discuss your mold test results with microbiologists who understand these molds more than anyone else.

Taking Mold Samples is easy! All you need is CLEAR SCOTCH tape and to follow the simple steps below.

1. Wear gloves if necessary.
2. Cut a few inches of clear scotch tape (2-3 inches). Avoid touching the sticky side.
3. Holding the edges of the piece of tape, press it gently to the suspect area. Apply light pressure to the non-adhesive side.
4. Peel tape off surface with slow, steady pressure, holding the tape edges only.
5. Without folding the tape, apply sticky side of tape (i.e., side with mold) to the inside of the plastic bag.
6. Close bag and label the outside of the bag with a brief description of the sample. For example:
   • Tape #1: Basement, east wall
   • Tape #2: Windowsill, master bedroom
   • Tape #3: Ceiling tile, bathroom
   • Tape #4: Under counter, kitchen sink.

   (NOTE: More than one mold type may be present. If several sites show visible mold growth, it is advisable to take more than one sample.)

7. Put only one sample in each bag.
8. Download, print and complete the sample submittal form. If you cannot print the form, get a blank sheet of paper and provide the following information:
   • Name
   • Address
   • Phone
   • Fax (if available)
   • Email address
   • The date the samples were collected
   • Credit card information for payment (Visa or MasterCard). You can also call us at 905-290-9101 to provide credit card information on the phone
9. Put the samples into a mailing envelope together with your completed sample submittal form (or the sheet you completed) and mail your samples to:
   
   Mold & Bacteria Consulting Laboratories (MBL) Inc.
   1020 Brevik Place, Unit 1A
   Mississauga, ON L4W 4N7
   Canada.

What to expect after the lab receives your samples

We’ll analyze your mold sample in our ISO 17025 Accredited laboratory and send you a lab report to tell you:

• exactly what type of mold your sample is
• whether your sample is a toxic mold or just a cosmetic problem
• if there are any known health problems associated with that mold and what they are
• how to safely remove it
• how to make sure it never comes back.

About Mold & Bacteria Consulting Laboratories

Mold & Bacteria Consulting Laboratories is accredited to ISO/IEC 17025:2017 International Standard. ISO/IEC 17025 is one of the most important accreditations for all types of laboratories performing tests and calibration.

Microbiology testing laboratories need to get accredited to ISO/IEC 17025 to demonstrate their technical competency and to ensure the accuracy of the test results. Having accreditation by regulatory bodies certifies that the results are consistent and accurate and are generated using industry-standard protocols.

Is black mold affecting your family’s health? Mold growth in homes poses a significant health hazard, depending on the level of exposure and sensitivity of individuals. Possible negative health effects include increased asthma-related symptoms, such as chronic wheezing and irritation, and other respiratory conditions.

There’s been a lot of news about black mold and its effects on our health in the past few years. It is important to know that black mold isn’t the only toxic mold that can affect your family’s health. Here, we use the term “black mold” to mean any hazardous mold regardless of color.

Are you or a member of your family suffering from black mold allergy symptoms or other mold-related illnesses? Molds such as Stachybotrys, Aspergillus and Penicillium are associated with adverse health effects. Others like Alternaria and Cladosporium are well-known to trigger allergic reactions such as hay fever and even asthma.

Who is most at risk of black mold exposure?

Everyone is at risk. However, the elderly, young children, the sick, and those with a history of asthma are at higher risk of suffering from mold related illnesses. So if you find mold in your home, it’s important for everyone’s health that it is tested and then removed right away.

 

If You Have Mold in Your Home, Don’t panic!

While all molds are potentially a health hazard, not all molds that occur indoors can affect your health, but even a small amount of mold growing in your home should be identified and removed. For $54.99 (Canadian dollar), you can have a mold test performed by an accredited laboratory in Canada.

How do you know if the mold is hazardous? Simply send samples to our lab for testing.

How to Collect and Send Samples to the Laboratory for Mold Testing

Do not spend money on expensive mold testing kits! Use clear scotch tape. It’s inexpensive, easy to use and works just like taking a fingerprint. The lab fee for this test is $54.99 (Canadian dollar) per sample.

Follow These Simple Instructions

1. Wear some gloves (which you can purchase from a pharmacy store).
2. Cut approximately 2-3 inches of clear scotch tape.
3. Hold tape at one end and place sticky side down onto the surface with visible mold growth and press gently.
4. Remove tape and stick it without folding onto a plastic bag (e.g.,ziplock bag).
5. Number each tape and identify the locations sampled. For example:
   • Tape 1: Basement, east wall.
   • Tape 2: Windowsill, master bedroom.
   • Tape 3: Ceiling tile, kitchen.
6. Enclose samples in an envelope or bag.
7. Download the mold sample testing order form and print it out. If you can’t print the form, you can provide the following information on a blank sheet of paper:
   • Your contact information including email address
   • Sample descriptions, i.e., where collected from
   • Credit card information, including billing address for payment purposes (we accept Visa or MasterCard)

(NOTE: More than one mold type may be present. If several sites show visible mold growth (with different discolorations), it is advisable to take more than one sample. Each sample is $54.99 (Canadian dollar))

Where to Send Your Samples

Tape mold samples do not require any special handling and therefore you can send them by post as ordinary mail. Enclose your samples in an envelope together with completed order form and mail them to:
Mold & Bacteria Consulting Laboratories (MBL) Inc.
1020 Brevik Place, Unit 1A
Mississauga, Ontario L4W 4N7
CANADA.
(Attn: Laboratory Manager)
Don’t delay. Left unattended, mold continues to grow. Send us your samples today!

What to Expect from the Laboratory

You’ll know whether the people living in your home are exposed to hazardous mold or not. The mold in your home will be properly and correctly analyzed because our mold testing laboratory is headed by someone with a PhD degree in microbiology who has worked in this field for over 30 years.
Within 3-5 business days (after we receive the samples), we’ll send you an easy-to-understand laboratory report:

• identifying the type of mold from your sample or samples,
• explaining any known health problems associated with the identified molds,
• and providing you with information on how to remove it safely.

Click Order form now to download our easy-to-use instructions. The form includes information you need to send together with the samples. Should you have any questions regarding tape sample mold test, please feel free to contact the lab directly at 905-290-9101.

The reality is that no house is mold spores-free since mold spores exist naturally in the environment. It is also important to know that depending on the time of the year, the majority of mold spores in the houses come from outside. These spores settle on various surfaces indoors and if still viable, they only need the right conditions to germinate and develop into visible mold growth.

No one want to buy a house that is known to have mold. Hence the presence of mold has a direct impact on the selling price. If you are a seller, failure to address the mold challenge properly prior to putting your home in the market may lead to your house losing value and incurring unwarranted costs.

As a buyer the presence of mold in a house gives you a better opportunity to negotiate for a lower price. The good news is that majority of indoor molds are not likely to affect the structural integrity of the house and therefore removing the mold would restore the home to it’s original condition. But before committing yourself to buying a moldy house, you may consider paying a qualified professional to assess the extent of mold contamination, identify the causes and estimate how much it would cost to rectify the problem. If the reduction in the buying price is higher than the amount you would spend to remove the mold, then there is no reason why you should not buy the house if you liked it.

Remove the Mold Before Occupying the House

If you decided to buy the home, remove the mold before occupying the house. It is easier to deal with the mold problem before bringing in your own stuff. The mold remediation should be performed by a qualified contractor who is familiar with the current mold remediation guidelines.

Damp and humid conditions provide the perfect environment for mold to proliferate. While majority of the common indoor molds don’t necessarily have an immediate effect on the property, if not removed early enough and the moisture eliminated the mold will continue spreading and damaging the aesthetic appearance of the house. Apart from damaging the house, elevated levels of mold spores indoors are a health hazard.

Below are some mold guidelines that a qualified contractor could follow to restore the house to it’s original condition.

1. Mould Guidelines by the Canadian Construction Association

2. Mould Abatement by the Environmental Abatement Council of Ontario (EACO)

3. Guidelines on Assessment and Remediation of Fungi in Indoor Environments by the New York City Department Of Health.

What You Should Know Before Buying the Moldy House

The cost of fixing the mold problem will primarily be determined by the size of the affected area and the location of the mold. If the mold extends throughout the walls or the HVAC system, then the cost may be far much higher than what you would save from a lower sale price.

The mold Cladosporium was first described in 1816. Members of Cladosporium are widely distributed worldwide and commonly found on all kinds of plant material, soil, food, paint, textiles and other organic matters. They are also found colonizing as secondary invaders leaves infested by other plant pathogenic fungi.

Cladosporium spores represent the most common fungal component isolated from air. Being small, dry and usually formed in branched, easy to break chains, Cladosporium spores are well adapted to be easily released into the air and spread in large numbers over long distances.

Medical Relevance of Cladosporium Spores

Most members of Cladosporium group do not cause disease in humans. Cladosporium spores are of medical relevance given that long-term exposure to these spores can cause adverse health effects, including allergies and asthma symptoms.

The mechanism of sensitization of human beings by molds in general is not well understood. However, there are several possibilities, among them inhalation of dried mycelia in house dust or inhalation of spores from outdoor or indoor sources. It is well known that spores of Cladosporium are common in indoor and outdoor air. Cladosporium herbarum, for example, is an important cause of allergies.

While there no established safe or unsafe levels of airborne mold spores, a concentration of 3000 Cladosporium spores m³ in the air has been suggested as a threshold value for clinical significance.

Prevalence of Cladosporium Spores in Indoor Environment

Cladosporium is one of the most commonly recovered molds from indoor air followed by others such as Penicillium and Aspergillus. In summer the levels of Cladosporium spores in outdoor air are very high. In fact, most of the Cladosporium spores found in indoor environment in summer originate from outdoors.

If you’ve seen mold in your home, don’t panic! Send samples for mold testing today.

A number of molds can sometimes be found growing in houses on drywall, wood, behind wallpaper, and on ceiling tiles in areas that are constantly moist or have suffered water damage or leaks. Some of these molds such as Stachybotrys, Aspergillus and Penicillium are associated with adverse health effects. Others like Alternaria and Cladosporium are well known allergens that trigger allergic reactions to sensitized individuals.

Not all molds that occur indoors are hazardous. However, current Canadian mold guidelines advise building occupants to clean-up and/or remove visible mold growth. To control mold growth, moisture should be eliminated or reduced.

For $50 per sample you can submit mold samples to Mold & Bacteria Consulting Laboratories to determine whether the mold present is hazardous or is only of cosmetic concern. Cleaning hazardous mold requires special protection. To collect a sample of visible mold, no special mold testing kit is required! Use clear scotch tape.

How to take Tape Samples for Mold Testing

• Cut off approximately 2-3 inches long of clear scotch tape.
• Hold tape at one end and place sticky side down onto the surface with visible mold growth and press gently.
• Remove tape and stick it onto a ziplock bag (Do not fold the tape).
• Number each tape and identify the sites sampled. For example:
  • Tape 1: Basement, east wall.
  • Tape 2: Window sill, master bedroom.
  • Tape 3: Ceiling tile, kitchen.
• Enclose samples in an envelope or bag

(NOTE: More than one mold type may be present. If several sites show visible mold growth, it is advisable to take more than one sample.)

Other Suitable Samples for Mold Testing

Pieces of wallpaper, drywall, wood, carpet and insulation material can also be sent for mold testing.

Sending the Samples

Submit the samples together with the following information:

• Name
• Address
• Phone
• Fax (if available)
• Email address
• The date the sample was collected

How to pay for the test

You may pay by credit card (Visa or MasterCard) or by calling 905-290-9101 ext. 211 or by PayPal by completing the form below.
 
After paying for the samples you can deliver them or send them by Canada Post to:
Mold & Bacteria Consulting Laboratories (MBL) Inc.
1020 Brevik Place, Unit 1A
Mississauga, ON L4W 4N7
(phone: 905-290-9101)
 

What You Get:

• Lab analysis of Mold samples collected by you using Clear Scotch Tape (see “tip” below)
• Lab report showing the types of mold present in your samples
• Results interpretation
• 15-minute free consultation (if requested) with one of our microbiologists
• Turnaround Time: 2-3 working days

Tip: If you see mold growth in more than one place (say kitchen, washroom, bedroom and basement), we recommend taking a minimum of 3 samples. This is because the mold in the washroom is highly likely to be different from that in the basement or kitchen or ceiling.

Additional Tape Lift or Bulk Samples…..$50/sample. THREE samples would therefore cost $150 tax included.

Got a Question?

Click Contact Link Below to Send us a Message or Ask a Question. We shall respond to you by Email.
Contact Us

The conditions during transit can cycle between hot and cold during the day and night respectively. During the day the high temperatures allow the air inside the container to absolve a lot of moisture from the sea and from the products and wooden pallets. As the temperature cools at night, this moisture condenses on the surface of the products.

Since the products often take several weeks (typically six to eight) to reach their destination the long duration in transit and the cycling between hot humid conditions and cooler conditions provide an ideal environment for mold growth. Products may also develop mold at their destination if stored in damp warehouses.

Products Prone to Mold Growth

Although mold will grow on a wide range of products including wooden pallets; leather products, textile, food products and paper goods are especially prone to mold growth. This is because these materials not only readily absolve the moisture but they are also a ready source of nutrients for mold growth.

Common Types of Mold on Imported Products

The damp conditions in shipping containers generally favor the growth of those types of mold that do not require a lot of moisture to grow. These molds, referred to as xerophilic fungi, grow and thrive under conditions of low water activity (Aw). Depending on the material, a wide range of molds may grow. In our lab the most common types of molds we isolate from imported products, especially leather and textile products include Aspergillus restrictus, Aspergillus versicolor, Aspergillus sydowii, Eurotium herbariorum (Aspergillus glaucus), species of Penicillium and many others. On wooden products you may find species of Cladosporium, Aspergillus and Penicillium.

Control of Mold Growth on Products

Mold growth on products can be prevented by controlling moisture and eliminating practices that contribute directly or indirectly to mold growth. Such practices are:

1. Use of contaminated raw materials;
2. Improper storage of raw materials and finished products in warehouses
3. Improper packaging and shipping of the raw materials and/or finished products
4. Faulty manufacturing processes that facilitate mold growth.

Determining if the Moldy Products can be Salvaged

While some mold may be visible on a product, it does not necessarily mean that the product has been damaged. Most products can be cleaned and restored to original condition. Mold & Bacteria Consulting Laboratories (MBL) can help you in the risk assessment and mitigation process by definitively determining the type of mold responsible for the damage, supporting the formulation of a clean-up plan, and developing testing criteria to determine safe-for-sale. MBL has a team of microbiologists with expertise on testing biological contaminants on imported products, evaluating clean-up strategies and assessing the suitability of the cleaned product for sale.

Water activity (a_w) refers to “free” water available for microbial growth. For microbial growth to occur, moisture must be freely available. The water activity of a material determines which types of mold would grow on that material.

Technically, the water activity is defined as the ratio of the vapour pressure exerted by the water in the material to the vapour pressure of pure water at the same temperature and pressure. Check out our Mold Inspection, Identification and Control course to learn more about Water Activity. 

Types of Mold based on Water Activity

Indoor molds vary in their water activity requirements and this ranges from 0.7 to >0.9. Higher a_w materials tend to support the growth of more microorganisms. Unlike molds, bacteria usually require a water activity of at least 0.91 a_w. Molds can be grouped according to their moisture requirements as follows:

• Extremely to moderately xerophilic. These molds are the primary colonisers and they are capable of growth below 0.8 a_w. Examples include Aspergillus and Penicillium
• Slightly xerophilic. These molds are the secondary or intermediate colonisers. They are capable of growth between 0.8 and 0.9 a_w. Examples of molds in this category include Altemaria and Cladosporium
• Hydrophilic. Molds in this category are tertiary colonisers and require at least 0.9 a_w for growth. Such high water activity can only be achieved through water intrusion and to a lesser extent high humidity and condensation. Examples of hydrophilic molds include Stachybotrys and Chaetomium

Check out our Mold Inspection, Identification and Control course to learn more about Types of Mold.

Note:

1. Xerophilic means “dry loving.” Thus, xerophilic molds are those that can or prefer to grow in “dry” environments. “Dry” is used here in relative sense since no mold can grow in a completely dry environment.
2. Hydrophilic means “water loving.” Thus, hydrophilic molds are those molds that require very high levels of moisture to grow.

Indicators of Water Damage

Water damage may occur over many months, mainly through roof leakage, but also via rising damp and defective plumbing, which result in mold growth. Indoor molds as well as bacteria are usually saprophytic, meaning that they obtain nutrients from dead organic matter. The nutrients are from the breakdown of simple to complex sugars such as starches, cellulose and pectin. The materials most susceptible to mold growth are organic materials containing cellulose (i.e. jute, wallpaper, cardboard and wooden materials). The tertiary colonisers are used as the indicators of moisture damage. The table below shows some of the most common indicators of water damage in buildings.

Indicators of excessive moisture or chronic condensation

If you liked this article you may want to check out our online courses.

• assess the airborne spore concentrations and the potential for human mold exposure
• justify remedial recommendations and implementation
• evaluate quality control and post-remedial assessments of mold remediation projects.

In an earlier article, Understanding Spore Trap Results, we discussed the factors that influence the reliability of spore trap results. These factors include:

• The amount of air sampled
• The non-uniform distribution of spores in the air
• Related to the non-uniform distribution of spores in the air, is the distance from the source to the air sampling point. For actively growing mold, the spore concentration is higher closer to the moldy structures/materials
• Changes in fungal spore types and concentrations within the day. The release of spores from moldy materials is not continuous and is dependent on ambient conditions such as temperature, air movement and relative humidity (rh). Ambient conditions also influence the types of spores released. For example, at very high humidity  fewer spores of Aspergillus/Penicillium are released than at low rh
• The experience of the analyst.

How to improve spore trap results

Bearing in mind the factors that influence the reliability of spore trap results, how can we then improve the spore trap results? Below are some suggestions on how we could minimize the effect of the above factors. Professional judgement is required as some of the some of the suggestions may not be applicable in every situation. Since most of the suggestions involve increasing the number of samples collected, it is important to evaluate whether the added cost and sampling time are worth it.

Amount of air sampled

By increasing the amount of air sampled we can improve the spore trap results. As was discussed in article, Understanding Spore Trap Results, by collecting 75L of air we’re sampling only 7.5% of 1000L, the ideal amount of air that should be sampled. Unfortunately increasing the amount of air especially in a dusty environment, would lender the spore traps difficult if not impossible to analyze. We therefore recommend collecting at least 150L or more whenever the environmental conditions allow. If sampling a dust free environment, collecting more than 150L would be recommended. If using the 15L per minute pumps, it would take slightly more than an hour to collect a sample which, to some extent, takes care of the changes of spore concentration with time.

Non-uniform distribution of spores in the air

Since the spores are not uniformly distributed in the air, the only way to minimize the effect of this factor is to take more than 1 sample at different locations within the same room. For example if collecting air samples in a room, you could take a sample from each corner of the room and one in the middle, that means a total of 5 samples. If dealing with huge open spaces, the number of samples to collect would be more. Also, if dealing with very tiny rooms, you could collect only 2 samples.

The spatial and temporal variability of spore concentration in the air

The spatial (relating to space) and temporal (relating to time) variability of spore concentration in the air can be minimized by taking samples at different locations and at different times within the day. For examples we can decide to take some samples at same locations early in the morning, at noon and in the evening.

Conclusion

The important thing is first to define the purpose for spore trap air sampling. Then design a sampling strategy that is practical and that would give you data good enough for your defined purpose.

References

Michael Oberle, Markus Reichmuth, Reto Laffer, Cornelia Ottiger, Hans Fankhauser and Thomas Bregenzer (2015). Non-Seasonal Variation of Airborne Aspergillus Spore Concentration in a Hospital Building. Int. J. Environ. Res. Public Health 2015, 12, 13730-13738.

Robertson, L.D and Robert Brandys (2010). A multi-laboratory comparative study of spore trap analyses. Mycologia January/February 2011 vol. 103 no. 1 226-231.

Hyvärinen A; Vahteristo M; Meklin T; Jantunen M; Nevalainen A; Moschandreas D (2001). Temporal and spatial variation of fungal concentrations in indoor air. Aerosol Science and Technology 35, 688 – 695.