7 Reasons Mold Testing Kits are a Scam
1) No visual inspection – By far the most important part of any mold investigation, before a single air or surface sample should be collected, is a strong visual inspection for evidence of water damaged building materials, water intrusions, leaks, and signs of visible mold growth. Without a source of water, mold is not likely to grow. Identifying the locations of these leaks, especially those that are not obvious, can be very difficult. A good visual inspection will incorporate infrared thermographic readings, moisture meters, borescopes, temperature meters, relative humidity meters, and dew point measurements . It should be performed by an inspector who has had years of training in the use of this equipment and in the understanding of building systems, exterior finishing systems, and identifying mold spores and the locations they are likely to grow.
The visual inspection is so important because it is the initial starting point from which an investigation must begin. Mold laboratory results are meaningless without knowing where the potential areas of growth are occurring. Recommendations for corrective actions are impossible without having first performed a visual inspection. Even if you hire a professional industrial hygienist to perform a mold investigation for you, without a strong visual inspection, you will have wasted your money.
2) No recommendations for corrective action - As mentioned above, recommendations for corrective actions are impossible without having first performed a visual inspection. Even if you hire a professional industrial hygienist to perform a mold investigation for you, without a strong visual inspection, you will have wasted your money.
Reading mold analytical results is a science in itself. Because there are no regulatory levels, determining whether an indoor air sample is “high” is very difficult. Industry professionals not only use the comparative outdoor sample to determine and indoor samples’ relative weighting, but also years of scouring over air sample results and the information gained during the visual inspection to determine their recommended corrective actions.
Even if you are able to discern that there is an indoor mold issue from the analytical results given to you by a do-it-yourself (DIY) mold testing kit, how do you fix the problem? Where are the elevated spore counts coming from? Where is the source of water that is causing this mold growth? Where is the mold in my home?
If there is obvious visible mold growth, then there is likely much more that is hidden from the eye. What are the corrective actions needed to effectively clean-up the mold?
All of these answers should be given in a thorough mold investigation report performed by a professional industrial hygienist.
3) DIY mold testing kit lab results are not meaningful – There are multiple types of mold testing used by professionals and in DIY mold testing kits. Some DIY kits test for “viable”, or living, spores only. These kits use a growth medium, called agar, that is added to a petri dish. You then let the samples sit for a determined period of time, put the lid on the sample, and send it to a lab. The problem is that these are passive sampling devices, without a predetermined volume of air that is being sampled, with a sampling media that is easily contaminated, and with analytical results that are almost meaningless in terms or indoor air quality and in using as a comparison to spores found outdoors. These results are not quantitative.
A professional industrial hygienist would never use this type of passive sampling to identify mold spores. When we do perform “viable” sampling, using a sterile petri dish and agar, it is performed using an impactor connected to a high-volume sampling pump, that actively samples a specified volume of air, giving an analytical result in a quantifiable unit, such as colony-forming units per liter of air (CFU/L). Passive sampling analytical results will only be reported as the arbitrary number of colony forming units per plate, in other words, those spores that have happened to land on the petri dish and of those spores, only the ones that were viable enough as to be able to grow on the agar medium.
These “viable” spores are only a small percentage of the actual spores found in the air. “Non-viable” spores make up a huge percentage of spores found in the air and are also of a health concern for many people. The “viable” spores that Do manage to land on that petri dish are in direct competition with other spores that have landed on the dish. Meaning by the time the sample is analyzed, only a small percentage of the spores found in the air are represented on that petri dish.
Some DIY mold testing kits include a sampling pump and “spore trap” type sampling media, which allows for the testing of “viable” and “non-viable” spores. In section 4 below, we go into more detail as to why these types of kits are problematic.
Various mold genera competing in an agar dish.
4) Sampling pumps are not properly calibrated – Some DIY mold testing kits provide a sampling pump at an additional cost. These pumps are attached to a “spore trap” type sampling media, allowing the homeowner to perform sampling for “viable” and “non-viable” mold spores. While this type of sampling is intrinsically better than the passive sampling using only agar and petri dishes, it can be provide wildly inaccurate analytical lab results.
The pumps included in these kits are cheap, inaccurate, and uncalibrated. Calibration of sampling pumps is a give-in when performing professional mold sampling. While the type of sampling pumps used by professional industrial hygienists are much more sturdy, even without having been shipped across the country, they require consistent calibration. In good industrial hygiene practice, these pumps are calibrated before and after each sample is collected. This calibration is performed using a secondary calibration device, such as a rotometer. In turn, the rotometer is periodically calibrated by a primary calibration device, such as a bubble-meter.
Without these calibrations, there is no way of knowing the volume of air that is being collected and thus the specific amounts of mold spores found in the air. Without regular pump calibration, none of the analytical results received should be trusted.
5) Not advised by trade organizations within the mold industry – Mold industry trade groups, such as the American Industrial Hygiene Association (AIHA) and the American Conference of Government Industrial Hygienists (ACGIH), do not recommend mold air or surface testing or DIY mold testing kits. These groups know that without a visual inspection, sampling is meaningless, because of the difficulty in interpreting analytical results.
The EPA recommends that “Sampling for mold should be conducted by professionals who have specific experience in designing mold sampling protocols, sampling methods and interpreting results.”
6) Problems with sampling media – As mentioned above, “viable” mold spore sampling media such as agar can easily become contaminated when prepared outside of a laboratory setting by individuals without the proper training. These samples are also being shipped across the country without the proper chain of custody and quality control protocols, meaning the lab results, at best, should be taken with a grain of salt, and at worst, are completely unreliable.
Sampling media such as “spore traps”, must be very carefully shipped, as they contain glass slides that can easily break. These glass slides can also become completely ineffective if they have been exposed to temperatures that are too hot or too cold, as they contain an adhesive that is temperature sensitive.
Any form of sampling media should come with an expiration date, after which, they should not be used.
7) Consumer Reports – Organizations such as Consumer Reports, have consistently advised against the use of DIY mold testing kits, finding them to be unreliable.
We here at Viva EHS are 100% for people taking mold and water issues within their homes seriously, as an indoor air quality issue and a potential health risk. We want only for everyone to be able to live in a home that is safe from these types of issues. While we are biased, because we have dedicated our lives to this profession, we truly believe that DIY mold testing kits are waste of your money and not a useful alternative to hiring an industrial hygienist to perform a thorough mold investigation.
Please feel free to give us a call any time if you have questions about this topic, if you need advice, or consultation regarding mold issues. 215-550-1417. https://www.vivaehs.com/contact
Sincerely,
Steven A. Vena, CIH President, Viva Environmental, Health, & Safety, LLC.
https://www.epa.gov/mold/mold-testing-or-sampling
Macher JM, Chatigny MA, Burge HA Sampling airborne microorganisms and aeroallergens. In: Cohen BS, Hering SV, eds. Air sampling instruments for evaluation of atmospheric contaminants, 8th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, Inc., pp. 589-617