Hello and welcome to this week's broadcast. My name is Dr. Cameron Jones. I'm an environmental microbiologist and thanks for joining me. Today I am talking about Bio-Tape lifts and I'm going to be running through some of the pros and cons about Bio-Tape lifts.
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Now, why would you use these things rather than Petri plates or Air-O-Cell cassettes?
Well, they're really a fantastic method for taking surface samples of visibly mould contaminated surfaces. I'm going to be running through some examples here on this live stream, and I'm going to be showing you for example, what it looks like under the microscope, and for example... Last week we went out, and did I a post remediation verification on a building, and we found mould all over this plasterboard, which the remediators had claimed had been fully cleaned. This is one of the benefits of using tape lifts, because you can pretty much very quickly work out whether or not a surface is or is not contaminated, and you've got the documentary proof to put into reports, in this case send back to the insurer, to show that it that it was in fact I failing post-remediation verification.
Before I move too quickly into some of the pros and cons of Bio-Tape lifts, I want to talk to you a little bit about the history of these really fantastic devices. Now, Bio-Tape lifts have an ANSI Standard, which is fantastic, and I'm going to be putting all these references in the show notes at the bottom.
Basically, the Standard is called the standard test method for direct microscopy of fungal structures from tape, and it's designation is D-7658-17. In 2017 it was revised, and it's a current Standard, and the scope or rationale behind tape lifts is that they are an optical microscopy method for the detection, and semi-quantification, and identification of fungal structures in tape lift preparations. The key phrase here is semi-quantitative. So, in a sense they are not as good as Air-O-Cells, but they tell you something different about how water damage impacts on a building.
I want to just give you a bit of an example of why this is a big issue. So, I mentioned before that this standard test method for direct microscopy, you can purchase this, and you can go to the astm.org website, but when you actually go out on site and use Bio-Tape lifts, I should mention that in many cases when a home becomes water damaged the framing timbers are one of the key elements of the building that require restoration, and restoration may take the form of source removal, or it may be physical remediation of water damage to this. So, tape lifts are one of the methods of determining either before remediation occurs to work out whether or not you do have a problem, because sometimes timbers can just look discolored, and yet people are very worried about mould being a problem.
In other cases, if there's been a severe water ingress event, then there can be some severe mould problems on these framing timbers, and they're particularly useful to use. So, if for example, I show you now under the microscope exactly what we see on some of these framing timbers. Just get the microscope working now. Often I like to white balance what I can see.
This for example, was taken from a plasterboard wall. Now, the remediators were tasked with carrying out remediation on this water damaged property, and yet the client was particularly concerned that it still felt mouldy to her. I asked her why she felt that and she said that, look, she knew that water actually cascaded through the light fittings, and that from her point of view, the remediators had sort of done 80% of the work, but for some reason they had left a lot of the original plasterboard in place, and just cut 60 centimeters from the floor.
So, you can actually see this in the photograph here that basically there was a a lot of remaining plasterboard. Now, water came down from the top of the dwelling, and so when we take tape lifts, and this is just at a hundred times magnification, if I zoom up to 400 times magnification you start to be able to see these mould spores, and chains of fungi very, very, very clearly.
Now, if this hadn't been tested for, this lady's property would have been essentially plastered over, and all of this mould would have been hidden in her walls. That's not really a good thing at all. One of the other things that I want to highlight as well is that tape lifts are particularly useful to use in other situations. Certainly, in many properties which have poor insulation and condensation issues. Many energy efficient apartments that don't ventilate will end up with serious internal window condensation problems, and in many cases homeowners, and tenants who are residing in these apartment complexes ring me up, and tell me that they've got serious water condensation inside. Especially over winter, whenever they run their heaters, and that although they ventilate water accumulates on the internal windows. So, often we are looking for a quick method to test for this presence of mould, and then provide these reports, either to the property manager, or body corporate, or the owner to prove that there is in fact a problem.
I'm going to show you a few more examples of where tape lifts are valuable, but I'm gonna play you an example of where framing timbers are mould effected, and this is from a well-known builder that advertises on the radio all the time, and they got me in because the owners were very concerned that during construction their timber framing had really gone a shade of green and black, and so they wanted to determine whether or not the effected timber framing was in fact mould contaminated. So, tape lifts along with viable sampling is one of the methods that we used.
Another great method for assessing for mould on suspect timbers, especially if they've been flood affected, and storm damage like this house undergoing construction, is to use these tape lifts, which allow me to take an imprint of the suspect's surface, look at it under the microscope, and catalog what mould, hyphae, mycelium spores might be present. This gives us a great idea about whether or not these timbers can be salvaged, or whether or not they need to be replaced with new.
Okay. So, you get a bit of an overview of how a tape lifts can be used, but it's not just for water damage and mould. The US Department of Homeland Security recently published a paper focusing on the benefits of tape lift collection as a simple and effective approach for non-destructively testing for chemical signatures in a terror event. Similarly, tape lifts have been used in forensics to collect spore evidence to link a person's location with the environment by using mould and plants spores to link a person's whereabouts. So, tape lifts are particularly flexible in what they can tell you, but other papers, and again I'm going to put all of these in the show notes description, mould contamination in air handling units, or in air conditioners. Many people again ring us and say, look, we're getting a a smell out of their air conditioning, or heating, and what can be done?
Again, tape lifts are a very good approach to taking some samples from the environment to work out whether or not there's any microscopic evidence of mould. Similarly, in this plasterboard example, there are some outstanding publications on cleaning methods and how effective they are at actually reducing microbial contamination and biofilms from bacteria, yeast, and of course fungi. So, tape lifts are particularly useful for this.
Before I go back to the microscope, I also want to mention that tape lifts are also extremely useful for doing contents assessment, and I can't tell you the number of times we received telephone calls saying, "Our home contents is water damaged. What can I do about it?"
Well, the thing with home contents is that if they've been in a water damaged building, and the water damage was not quickly addressed, usually in the first 24 to 48 hours. If you can smell mould, if you're getting adverse health reactions, then it's very probable that your home contents could at some stage be exposed at least to the air stream containing these mould spores.
In this particular example, you can see that the visibly mould affected. Now, I want to give you another quick example now about a leased property, and we were called into this maybe two months ago, a high end property in an expensive suburb in Melbourne. The tenants were paying several thousand dollars per week. They were very upset that every time they drove into the underground car park and walked upstairs that they were hit with this very strong mould smell. In fact, when the lady called me, she told me that the basement appeared covered in this green dust, and so here is what I found and here's how tape lifts were used.
I'm shooting this quick little video. I know it's a little bit hard to hear me, but I'm downstairs in this property, and you can probably see the mould on the timber paneling behind me. I'm going to use something called a tape lift to take a surface impression, so that I can have a look at this under the microscope. I'll show you how to use these. Basically, you just need to lightly press this onto the area or the region of interest. Then I'll take that back to the lab and see what I see under the microscope. This downstairs basement is going to need significant mould remediation.
Okay. So, you can see that they are a very flexible method of collecting evidence that really people can't argue with, and so I like these a lot. Now, my final example comes from a property that I had just inspected on earlier this week, and I haven't done the spore traps on this property yet, but what I can show you in this property is that this is from a master bedroom, and wife who spends her time, and sleeps in this bedroom, has just recently been diagnosed with CIRS, or chronic inflammatory response syndrome, and she is extremely unwell.
Her husband tells me that they got married approximately nine years ago and that for the last seven she has been experiencing a whole range of adverse health impacts. In any case, when both of us moved some of the furniture around in the master bedroom, we could see that there were these really serious evidence of mould coming through, and the infrared thermal image on the bottom right hand side shows you that in a sense this property has got a serious rising damp issue. Although it's a timber frame home, it has a whole bunch of thermal bridging impacts around the window frame, and it's particularly cold.
So, in a sense you're getting condensation again forming on the internal framing of the home, and because it's very warm indoors, especially over winter, the way their heating system is arranged. There are big issues of mould appearing, and I suspect that when I finish all the spore traps that they too are going to confirm a serious indoor air quality problem, because the particulate matter counts already filed very badly. However, I am now going to show you what this particular property looks like under the microscope, and again, I will want balance this. This is from the lady who has the chronic inflammatory response syndrome. So, when I zoom in on the microscope now here, and I make this just sharper, you can see all of this mould mycelium. Again, this is just at a hundred times magnification. How about we zoom in and look at some of this fungal hyphae and mycelium a little bit closer. So, I'll move this up to 400 times.
Here are these long filaments that branch off the fungal hyphae, or the mycelium, and there is lots of this over there. So, I just have to make sure I don't move off the microscope slide. Again, even though the Standard says that you can speciate very effectively from the tape lift, it's a lot harder to do than the standard specifies. So, you can certainly do total counts, and surface area coverage, and work out the concentration of mould present in the property, in this case on the wall, but it's much more difficult to speciate this. So, these deposits really look quite ugly in a sense, but they certainly confirm that this woman is in fact being significantly affected by mould in her home environment, and this is the evidence to prove it.
So, I want to go over some of the negatives associated with tape lifts, because if I open these up they essentially are a very small microscope slide, and they have a sticky section on it, and the concept as you've seen on the videos is just to press this against the target surface, but as you can appreciate if I was to turn around, And just do this on my wall, and unscrupulous assessor could potentially put this on an area that is not mould effected, or not suspected of being mould effected, and potentially write up a report which concludes that a home doesn't have a problem when in fact there could be a serious problem, and the very small sticky surface area of the slide means that it shows something called sampling bias.
So, be very aware of sampling bias. Hence why all indoor mould and air quality investigations really must use multiple methods of assessment, because mould is a serious health threat, but not withstanding that, tape lifts are fast, efficient, inexpensive, and you get pretty much fast results to inform a remediator that there either is or isn't a problem, or that the job is complete.
In any case, that's the main points that I wanted to get across in this week's livestream. I'm going to put in the show notes, and the descriptions for here on Facebook, and also onto YouTube, some reference materials so that you can follow up yourselves. Next week I'm going to be talking about spore traps, because spore traps are extremely useful in doing any type of indoor air quality and mould inspection. I'll be showing you some great examples of this also under the microscope. Bye for now.
ASTM D7658 - 17 - Standard Test Method for Direct Microscopy of Fungal Structures from Tape. https://www.astm.org/Standards/D7658.htm
Stephen C. Wilson , Robert N. Palmatier , Larysa A. Andriychuk , Jared M. Martin , Cynthia A. Jumper , Homer W. Holder & David C. Straus (2007) Mold Contamination and Air Handling Units, Journal of Occupational and Environmental Hygiene, 4:7, 483-491, DOI: 10.1080/15459620701389909. http://dx.doi.org/10.1080/15459620701389909
Michael Krause , William Geer , Lonie Swenson , Payam Fallah & Coreen Robbins (2006) Controlled Study of Mold Growth and Cleaning Procedure on Treated and Untreated Wet Gypsum Wallboard in an Indoor Environment, Journal of Occupational and Environmental Hygiene, 3:8, 435-441, DOI: 10.1080/15459620600798663. http://dx.doi.org/10.1080/15459620600798663
Brady, K., Stilley, B., Olds, M., O'Neill, T., Egan, J. And Durnal, E. (2017). Tape Lift Sampling of Chemical Threat Agents. Journal of Forensic Sciences. 62(4): 1015-1021. doi: 10.1111/1556-4029.13363