After extensive research, we have chosen not to use any type of DNA mold testing at this time. Here's why:
1- These tests were conceived by the federal government in political haste. 2- DNA testing protocol was established by potentially flawed sample data gathered from unscientific means (see below 1st paragraph). 3-The amounts of drawbacks with the "old" type of testing are found just as much if not more, with DNA based testing (also see mid-bottom of this page). 4- DNA based testing limits the amounts of molds found in their tests compared to the "old" style of testing (also see ERMI & ARMI on this page). 5- Although DNA was stated as partially being designed to be cost effective for homeowners, these tests can cost over twice or even three times the amount as "old" testing (see 2nd paragraph below). 6- The creation of DNA standards was flawed , as stated by the federal government. 7- DNA whole house mold testing may not cover all areas of the house (see 2nd paragraph below) although, they imply that they do.
Where Was EPA Mold Standardization Data Gathered From? The Genesis of DNA Mold Testing
Currently the EPA whole house mold testing protocol is sampling(s) "from the living room and from the bedroom". What happens if the bedroom and living room are on the first floor and the second floor is not used for sleeping or living areas? Maybe that is why some EPA publications state "upper and lower floors". You can see the scientific shortsightedness of the former testing recommendation. Does upper and lower floor mean the basement and second floor or the 1st floor and second floor omitting the basement or first floor? Basements by far are the most prevailing area of the house in which molds form. That's the main reason why we (mold inspectors) get called in the first place. Most basements in the Cincinnati - Dayton Ohio area that we inspect/test are considered livable. They have carpeting, furniture, heat & air conditioning, entertainment equipment and etc. Mold spores have a tendency to settle to the floor when becoming air borne. Additionally most people keep their interior & exterior basement doors closed.
It appears that the ERMI test does not specifically take into account the most important area in its mold testing recommendations (the basement), in regards to determining whether or not there are elevated mold levels inside a building. Again, great news for the insurance industry and bad news for you. Maybe a AMRI test (detecting only 12 mold species) is in order in the basement (although the EPA states that only 2 EMRI location tests are needed for the entire house)? That makes 3 areas to be tested. These tests were partially developed by the EPA to keep mold testing costs lower. The 2 (if only one is used used on each floor) EMRI and one AMRI tests would total around $625.00 just for the test kits alone (labor not included - Jan. 2010). Air O Cell (traditional air Sample testing used by professionals) testing for 3 floors is around $275.00 and performed by a certified mold tester. The EMRI & AMRI kits are sold to entice the non-professional homeowner into performing their own mold testing experiments by making the kits available to the public without the need for professional air sampling equipment, in some cases.
Insurance companies who handle mold claims will not accept mold testing results from the non-professional homeowner-mold tester and will require professional testing to be performed prior to any claim.
The ERMI Carpet Baggers
The ERMI test is performed by vacuuming sections of carpeting as described above. This test is considerably higher in cost and is gathered by vacuuming portions of the carpet for 5 minutes. One of the problems with this test is, it is all scientific theory with no practical field experience. If one were to take a carpet sample using the recommended testing method, this test would not take into account that many carpets are improperly installed without a sufficient moisture barrier. This in turn will have a tendency to grow mold(s) on the carpet from the moisture in the concrete floor and trapped between the padding (assuming that padding is installed). Not only will the carpet perhaps grow mold(s) but more so the padding underneath. So when a vacuum sample is taken from the carpet, the mold(s) from the padding that are not regularly introduced into the air, will come up (if it is one of 36 species) in the test. When it does, the inaccurate result will be applied as if the mold is present throughout the entire air space of the house giving inaccurate air readings and prompting unnecessary remediation costs. Unfortunately again, some of the same drawbacks of the ARMI test apply here as well.
Be All That You Can Be......In The ARMI
There are thousands (millions per the EPA) of known species of molds, which include opportunistic pathogens, saprotrophs, aquatic species, and thermophiles. The ARMI dust swab method only tests for 13 species that were identified by the EPA to be geographically specific to the region (Ohio) tested. Once again, a determination of toxicity in molds is an ongoing process. Science has not yet identified thousands of molds in regards to human health effects and is consistently updating their data. By limiting the amount of molds that can be analyzed, not only by number but by theoretical geographically "specific" data which is also subject to the frailties of misinterpretations or incomplete information; this puts you in the position of having to properly retest the area if your mold issues are not addresses by the limited ARMI testing protocol.
An ARMI sample is obtained by collecting dust (via swab) from virtually anywhere in the building. Professional testers now collect a swab sample from a specific area that have a discoloration resembling mold(s), moisture laden areas, insect farmed areas and etc. The ARMI takes this dust sample and if any elevated molds are found, implies that those molds are constant throughout the entire area tested and even the whole home (HVAC filter) without any regard to where or why the mold originated from (the exterior & etc). This is why it is so important to have a mold inspection performed on the building.
You may be able to determine (limited to 13) that the house has mold(s) in a particular dusty place by using the ARMI test but, you will not know where or why the mold has formed without professional evaluation. Cleaning the mold(s) will have little effect if the causes for the molds are not identified.
"However, the ERMI is not a health-based standard but rather simply a method to compare levels of mold in a home environment to a representative sampling of homes across the nation. From this comparison, one can conclude that a home is overburdened (or under-burdened) with mold compared to the average home; but, as even the most ardent proponents of using the standard agree, there is no proven correlation between the level of mold in a home and particular health conditions.".
The attorney the goes on to
note that "The ERMI approach starts with a highly scientifically accurate sampling of mold, using a specialized vacuum device to scoop up dust particles for mold measurement (as opposed to air sampling, which up until recently was the usual method to collect samples for mold measurement). Whereas air samples reflect a very short duration of measurement in a potentially changing environment (i.e., air currents can vary from time to time), the dust sample is relatively stable, reflecting as the sample does materials that have collected over a relatively long period of time in such media as carpeting.".
Although the attorney is correct in his assessment
or ERMI based testing and also air sample testing, it must be noted here that the carpeting in which the ERMI test is drawn from is susceptible to environmental variations just as much or even more than the air o cell (air sample) testing is.
ERMI (carpet) test results are subject to floor spills, high basement humidity levels, concrete floors, pet stains, wet shoes, plumbing malfunctions, carpet cleaning, unseasonably high humidity levels, foot traffic, improper crawlspace ventilation, the opening and closing of doors & windows and to which, are designed to accumulate most of all the settled air born mold particles in undefined periods before vacuuming. The results are then applied as if the entire building airspace was under those very same conditions. Speaking of vacuuming, it is recommended to all of our clients (What to do prior to a mold inspection - testing) that they do not vacuum at least 48 hours prior to any air sample testing. In fact this is so important that we have included this in all of our pre-services agreements. We are aware of no recommendation of this for the ERMI testing at this time.
Although ERMI, ARMI, PCR, DNA & MSQPCR look promising for the future, currently the methods to extract the samples are relatively primitive. Some labs have recently advertised PCR air sampling, although this is relatively new and unproven in the industry and by the EPA at the time of this writing. Also, some labs have distanced themselves from the EPA “ERMI” and “ARMI” terms and have relabeled these tests as PCR.
Critics and professional mold test users of Air O Cell Sampling are aware of the limitations of these devices. Unfortunately, we can not usually rely on one single method to determine whether or not a building has elevated or unusual mold levels. Air O Cell sampling, even with its faults, is still the single most cost effective way in determining indoor air borne mold levels, within a specific amount of space. Combined with a certified mold inspection and potentially other methods of testing, there is no better way at the time of this writing to as effectively determine elevated interior mold levels. But once again, the extensiveness of any testing performed is the sole decision of the client.
Which would be more precise? An air sample that is subjected to natural exterior and interior air flows or a carpet sample which amplifies the very same air flow variations in the accumulations of once air borne molds, delivered through settled household dusts and mold spores, over an unspecific period of time?