Dr Jackson Kung'u- Mold Specialist

Helping People Resolve Mold Problems

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Air Quality Mold Testing Kits

Air quality testing should be conducted by a qualified professional. However, there are basic tests that a homeowner or a property manager can perform by themselves and save money. Air quality testing for mold does not require any special training. Mold & Bacteria Consulting Laboratories has been renting air quality testing equipment to homeowners, property managers or professionals who are just starting their businesses.

To perform your own air quality testing for mold it’s important to plan ahead. For example you need to decide how many rooms you want to test as this will determine the number of air samples you will collect. ideally, one should test all the rooms but if the budget cannot allow you can test areas of concern. In addition to the samples you collect from indoors, an outdoor sample is also required. The outdoor air sample helps to determine which of the mold spores detected indoors had likely originated from outdoors.

Interpreting air sample results can be difficult. However, after comparing indoor samples with outdoor sample, if the types of spores detected from the indoor sample are the same as those detected from outdoors and the indoor counts are significantly lower than those of the outdoors, then we can conclude that the tested areas had no mold problem at the time of testing. This conclusion is only valid if we cannot visually see mold growth and the building is not damp. It’s important to note that while the spore counts could be low, presence of certain types of molds could be an indication of major moisture damage and possibly hidden mold growth.

 How to perform air quality testing

As indicated previously you’ll require to rent an air sampling pump. You’ll also need to purchase air sampling cassettes. Mold & Bacteria Consulting Laboratories provides instructions on how to operate the pump. After sampling the samples are sent to the laboratory for identification and counting of spores. The results are reported as the number of spores per cubic meter of air. Click air sampling instructions to watch a video on how to perform air quality test for mold.

Mold Testing Laboratory In Toronto

Mold & Bacteria Consulting Laboratories (MBL) is a leading mold testing laboratory in Toronto Area (GTA) and the rest of Canada.

As a mold and bacteria laboratory, the lab specializes in the analysis of air and surface samples for:

  • Bacteria including Coliforms, E.coli, Legionella testing, and total aerobic and anaerobic counts
  • Mold analysis by culture methods: culturable air samples such as RCS, BioCassette, Andersen, SAS, etc.
  • Mold analysis by direct microscopic examination: tape, bulk, swab, and water samples
  • Total airborne fungal spore counts: Spore traps including Air-O-Cell, BioAire, and Micro5 cassettes, Allergenco, Burkard and BioSIS slides

MBL’s mold and bacteria testing services are not restricted to the Greater Toronto Area (GTA). We serve clients in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, Nova Scotia and New Foundland.

MBL clients include:

  • Industrial hygienists
  • Environmental consultants
  • Quality assurance managers
  • Home Inspectors
  • General contractors
  • Cleaning and restoration contractors
  • Property managers
  • Insurance, financial, or legal professionals who deal with microbial contamination issues

For questions related to laboratory testing of samples, sampling methods, laboratory  data interpretation and other issues related to microorganisms, please call 905-290-9101 (within Toronto area) or 1-866-813-0648 if calling outside the GTA.

MBL is Proficient For Bacteria Testing

The Canadian Association for Laboratory Accreditation Inc.(CALA) has rated MBL proficient for the following bacteria testing:

Test Parameter Method Of Analysis Status
Escherichia coli (E. coli) Membrane Filtration (DC-Agar) Proficient
Fecal (Thermotolerant) Coliforms Membrane Filtration (mFC) Proficient.
Heterotrophic Plate Count (HPC) Membrane Filtration (PCA) Proficient
Total Coliforms Membrane Filtration (DC-Agar) Proficient.
Escherichia coli (E. coli) Presence/Absence Proficient
Total Coliforms Presence/Absence Proficient.

Coliform Bacteria

The coliform bacteria are used as indicators of potential health risk for water. Coliforms are divided into 2 groups; total coliforms, i.e., all the coliform bacteria; and the fecal coliforms. The fecal coliforms are dominated by Escherichia coli (E. coli). E. coli are common in human intestines and they are generally harmless. However, some strains such as 0157 can cause serious infections.

Presence of fecal coliforms in water is widely accepted as indicator of potential contamination of water with fecal material. Contamination of water with fecal material presents greater risk of infectious microorganism such as viruses, other bacteria, protozoa and even worms.

Acceptable levels of total aerobic bacteria, yeast and mold in buildings

Question: What is the “normal / acceptable” level of total aerobic bacteria and yeast & mold in homes / buildings

Answer: There are no universally agreed acceptable levels of total aerobic bacteria, yeast and mold in buildings. However, you may find levels suggested by various organisations. I would say that since there will always be bacteria/mold/yeast in houses, any levels that appear abnormally high is uncceptable. However, apart from the levels, you have also to consider what organisms are present since some are more harmful or destructive than others.

The tables below show some levels published by the Commission of the European Communities in Indoor Air Quality & its Impact on Man: Report No. 12: Biological Particles in Indoor Environments. ECSC-EEC-EAEC, Brussels-Luxembourg, 1993.

Categories of CFU/m3 (mixed populations of fungi) obtained with the Andersen six-stage sampler in combination with MEA, and with the N6-Andersen one-stage sampler in combination with MEA and DG18.

Category Fungal Counts (CFU/m3) in Houses Fungal Counts (CFU/m3) in non-industrial indoor environments
Very low <50 <25
Low <200 <1,000
Intermediate <1,000 <500
High <10,000 <2,000
Very High >10,000 >2,000

N.B.: These categories are based on the range of values obtained in indoor environments and not on a health risk evaluation.

 

Categories of CFU/g dust (mixed populations of fungi) obtained by direct
plating on V8 or DG18, and by suspension in peptone followed by plating on V8 or DG18, for houses and other non-industrial indoor environments

Category Method
  V8/directa DG18/directa V8/peptoneb DG18/peptoneb
Very low <1,000 <2,000 <10,000 <10,000
Low <2,500 <6,000 <20,000 <20,000
Intermediate <5,000 <9,000 <40,000 <50,000
High <10,000 <15,000 <100,000 <120,000
Very High >10,000 >15,000 >100,000 >120,000

a : direct plating of 30 mg dust

b: 100 mg dust suspended in a pepton solution (1 : 50), 0.1 ml of the solution plated on the medium

N.B. : These categories are based on the range of values obtained in indoor environments and not on a health risk evaluation.

 

Categories of CFU/m3 (mixed populations of bacteria) obtained with the
Andersen six-stage sampler or slit sampler (sampling time 10 – 15 min.,
incubation at 20 – 25°C for 3 – 5 days), for houses and non-industrial indoor environments.

Category Bacterial Counts (CFU/m3) in Houses Bacterial Counts (CFU/m3) in non-industrial indoor environments
Very Low <100 <50
Low <500 <100
Intermediate <2,500 <500
High <10,000 <2,000
Very High >10,000 >2,000

N.B.: These categories are based on the range of values obtained in indoor environments and not on a health risk evaluation

Bacteria As Contaminants In Indoor Environments

People spend around 80 and 90% of their time in indoor environments (office, school, home, etc) and there is increased awareness of the potential health effects of indoor biological contaminants such as bacteria. Therefore, when considering work or indoor living conditions, the air quality requires special attention.

In indoor environments, biological contaminants are often found in areas that provide conducive conditions for microbial growth. These include damp or wet areas such as cooling coils, humidifiers, condensate pans, draperies, bedding, carpet, and other areas where dust collects.

Bacteria are an important component of indoor biological contaminants. Some of them are pathogenic (that’s they are capable of causing disease) and are involved in respiratory diseases. If the environmental and nutritional conditions are favourable bacteria can colonize and grow on many surfaces (including standing water) from where they and their by-products can become airborne. A number of diverse activities can result in the dispersion and generation of bacterial aerosols indoors, for example, the operation of heating-ventilation-air conditioning systems, hot water systems and water spray devices.

Health Effects Associated With Indoor Bacteria
There are several health effects associated with exposures to bacterial aerosols. Some of them include irritative and nonspecific respiratory symptoms, respiratory infections, and allergic reactions such as alveolitis and chronic bronchitis.

Some of the infectious bacteria include Mycobacterium tuberculosis, Legionella pneumophila, Bacillus anthracis. These bacteria cause pulmonary tuberculosis,  legionellosis (Legionnaire’s disease) and anthrax respectively. Infection is primarily through inhalation.

Bacteria As Causes Of  Bioderioration
Bacteria are rarely thought of as biodeterioration agents. However, they are involved in biodeterioration of various types of materials. Bacillus sp, Nitrosomonas sp, Nocardia sp and Streptomyces are involved in biodeterioration of diverse materials in several regions. They cause physical damage and some are capable of producing acids that cause biochemical deterioration.

Conclusion
In general, several microorganisms including bacteria are present in indoor environments. They can contaminate indoor air and pose health risks especially when certain species are present or when they are in high numbers. Apart from the health effects microorganisms have the ability to cause damage to materials they are growing on.

Contact Information

Dr. Jackson Kung'u, PhD.
Phone: 905-290-9101
Fax: 905-290-0499