Vermiculite insulation produced or sold by Munn & Steele or Mica-Fil Brands:

Does Munn & Steele vermiculite insulation contain asbestos? What about Mica-Fill vermiculite insulation?

How are Mica-Fil or Munn & Steele vermiculite products identified, & what should be done about potential vermiculite-asbestos hazards ascribed to this vermiculite insulation?

This article series explains how to recognize vermiculite building insulation that may contain asbestos fibers. This article permits visual identification of vermiculite insulation; we include our own as well as US EPA photographs of various forms of vermiculite insulation to assist in recognizing vermiculite in buildings.

We provide photographs and descriptive text of asbestos insulation and other asbestos-containing products to permit identification of definite, probable, or possible asbestos materials in buildings.

Munn & Steele Vermiculite Insulation, Siscoe Vermiculite Mines, & Mica-Fill Vermiculite Insulating Products

Reader Question: did Munn & Steele Vermiculite Insulation Contain Asbestos?

I read your in depth article on vermiculite on the web. We began a DYI Reno on our bathroom (1945 row house in ... NY we just purchased) and came across a product in the ceiling closely resembling the vermiculite on your site. I have checked extensively on line and cannot find the manufacturer on the bag, meaning if it is asbestos or not.

[Click to enlarge any image]

The company is Munn & Steele and the bits of paper on the backing we could read had the words or partial words of Zonolite, mineral and Munn&Steele with a Newark NJ address.

What I have read is that not all zonolite has asbestos and the product coming from the Libby mine are asbestos. What I cannot find is if this particular company was ever a reseller or manufacturing of the Libby asbestos product or if they just used the term zonolite in their own micafil product.

The paper is brown and the Munn lettering is in black with red, while the Zonolite is in a light blue and the word mineral is in black lettering. The paper looks old - Like from the 40's or 50's. We stopped the clean up after a contractor we bought in to access the rebuild of the bathroom pointed out that he thought it was asbestos.

The substance is flaky and shiny. Do you have any info? I tried to download the image file in the EPA site of samples of bags if Zonolite but the file can't be opened for some odd reason.

History of Munn & Steele's Vermiculite & the Siscoe Vermiculite Mines

Reply: Munn & Steele's Vermiculite from the Siscoe Vermiculite Mines

John R. Munn, from an old Newark New Jersey family, was chairman of Munn & Steele Inc., makers of building insulation material, including vermiculite insulation.

Photo: Munn & Steele vermiculite insulation from a home in Franklin Square, NY, provided by an InspectApedia.com reader.

I could not find the company's vermiculite insulation, and it's possible it was a rebranded material from the most common source (the Libby mine whose vermiculite did contain asbestos).

However to be clear, not all vermiculite sold in the U.S. came from Libby - just most of it.

Interesting, there was a relationship between Munn & Steele and a different vermiculite source: the Siscoe Vermiculite mines[1] located in Quebec. Without a detailed review of the court records, we don't know if there was a product use or only a trademark issue.

Munn & Steele were a party in a much-cited 1957 trademark trafficking dispute with the Siscoe Vermiculite mine [3] whose vermiculite was also sold under the trade name "Mica-Fil" [2] and whose packaging as well as confusing labeling are illustrated below in this article.

Some of the vermiculite citations for Siscoe dated back to the 1940's and extended at least through the 1950's.

At this juncture, if we don't have the actual packaging of the vermiculite, without sophisticated testing we can't know for sure just what vermiculite mine sources were used when by various vermiculite insulation marketing companies as the principals are too-long gone to ask.

My search for records indicating whether or not Munn & Steele actually sold vermiculite that came from the Libby mine (or from the Siscoe mine) did not find any indicators suggesting a yes or no answer but it seems likely, since some of the MicaFil packaging specifically names the Siscoe vermiculite mine.

You know from your reading that not all vermiculite sources contain asbestos. I add that one cannot determine asbestos content in vermiculite by normal visual inspection. Polarized light microscopy (PLM) procedures are needed.

Watch out: Note that MicaFil and other vermiculite insulation products often sold across Canada and the United States, even when branded and packaged identically, may well have originated in different mines. So without more thorough forensic analysis of a vermiculite sample we won't be certain of the asbestos content of a particular Munn & Steele or Mica-Fil vermiculite product.

Interestingly the Siscoe vermiculite mine was a subsidiary of the Siscoe gold mine of which more was written.

Sources I found cite vermiculite mines in southeast Ontario and in Quebec and possibly in the Gowganda Ontario area where cobalt was of principal mining interest.

Some sources report asbestos in the Gowganda area so unless your tests find no asbestos in your vermiculite I would treat it as PACM - presumed asbestos containing material.

In 1959 Siscoe, principally interested in gold mining, sold its two wholly-owned vermiculite interests to a building supplier, Sidney Roofing & Paper Company Ltd. [7].

Photo: Munn & Steele vermiculite under the stereo microscope in our lab.

Since the most-asbestos-contaminated vermiculite in the U.S. came from the Libby Montana mine, that would have been a different source. Much (but probably not all) of the Libby Montana vermiculite was sold under the brand Zonolite.

If you can send me some sharp photos of your vermiculite and of any packaging or markings that would be very helpful.

With all that interesting and useless detail I have to add that even though your vermiculite may contain asbestos we just don't know unless you have a test performed. If you want to do that (please keep me informed) the cost is typically around $50. US. and you can find a lab

at ASBESTOS TESTING LAB LIST

Munn & Steele "Zonolite" Vermiculite Asbestos Test Results & Photos

Photos above (under the stereo microscope in our lab) and below (EMSL using TEM): Libby Amphibole asbestos fiber detected in our sample of Munn & Steele Zonolite™ Vermiculite insulation during tests conducted in January 2020.

In 2019 we asked a prominent national US testing laboratory, EMSL, to test a sample of Vermiculite that we knew, from its package labeling, was Zonolite™ Vermiculite.

• The test result for our sample No. 007 found less than 4 Libby Amphibole fibers in the sample.

Watch out: Keep in mind these limits of forensic microscopy. By the time a microscopic sample has been prepared for analysis a very small amount of the original bulk sample has been selected. The actual physical volume of material being sampled is extremely small.

When the bulk sample is coarse and not homogeneous, it is likely that different samples may produce varying results in the detection of asbestos.

It is entirely possible that other microscopic samples of the same bulk sample of vermiculite would find different, and perhaps higher levels of asbestos. Details are below.

• ASBESTOS TEST REPORT, VERMICULITE, ZONOLITE [PDF] 2020/01/23 (TEM Qualitative Filtration) Lab report summary.
  
  For our sample no. 042000629-0007
  
  Test result: Libby Amphibole < 4 fibers observed
• ASBESTOS TEST DETAILS, VERMICULITE, ZONOLITE [PDF] 2020/01/23 The sample was sent for analysis via TEM Qualitative Filtration
  
  For our sample no. 042000629-0007
  
  Results (TEM) The samples were analyzed with a transmission electron microscope (TEM) at approximately 20,000 X magnification. Asbestos structures are identified by a combination of morphology, quantitative elemental chemistry via Energy Dispersive X- Ray Analysis (EDXA), and Selected Area Electron Diffraction (SAED).
  
  042000629-0007 During TEM examination asbestos was detected on the sample.
• Contact: EMSL Analytical, Inc., 200 Route 130 North, Cinnaminson, NJ 08077 USA, Tel: 856-303-2500 - Fax: 856-786-5974 - Toll Free: 800-220-3675
  Lab Hours: Mon-Friday 7AM-10PM, Saturday 8AM-5PM, Sunday On-Call.
  
  Some of the resources EMSL Analytical, Inc. offers to our clients:
  
  LABConnect https://extranet.emsl.com/
  
  Order Products http://www.emsl.com/ProductCatalogHome.aspx
  
  Client Corner http://emsl.com/Page.aspx?ID=420
  
  Training http://emsl.com/Training.aspx
  
  Additional Resources http://emsl.com/Links.aspx
  
  Sampling Videos http://www.emsl.tv/

What to Do About Your Munn & Steele Vermiculite Insulation

The best way to minimize your risk of amphibole asbestos exposure is to avoid disturbing vermiculite-based insulation in any way.

If vermiculite-based insulation is contained and not exposed to the home or interior environment, it poses very little risk. - Health Canada

See the following

• HEALTH CANADA ADVICE on VERMICULITE INSULATION
• US EPA ADVICE on LIBBY MINE VERMICULITE
• WARNINGS BEFORE REMOVING ANY VERMICULITE INSULATION

Our photo shown above and below illustrate Munn & Steele vermiculite according to our New York reader.

The next vermiculite pictures shown here illustrate the reflective property of mica flakes that will remain even after most of the vermiculite has been expanded into its classic "concertina" form.

Comparing Packaging of Munn vs Steele Mica Fil Vermiculite

Photos above (provided by InspectApedia.com readers James Patterson and Michael Gou) illustrate packaging and labeling information for two versions of MicaFil vermiculite insulation.

(Feb 9, 2018) James Patterson said: I found a bag in the attic space of my 1952 built home. Bag is Vermiculite Micafil and indicates manufactured by Sicoe Vermiculite Mines ltd in Cornwall Ontario under franchise from Munn and Steele Inc of Boston Mass. . Probably going to have it tested but wondered if this is possible safer given the source location?

Reply:

James: I have found a 1957 report naming a Steele mine and am researching that inspectapedia.com/hazmat/North-American-Geology-1957-USGS.pdf and some history of Munn is at vredenburgh.org/mining_history/pdf/AMJ-1941-pt2.pdf

Micafil vermiculite insulation was distributed and sold in both Canada and the U.S., though the packaging of the vermiculite varied. Our first photo above illustrates Munn and Steele's Mica Fil vermiculite sold out of Boston and providing three different corporate names:

• Bishop Asphalt Papers Ltd., Portneuf Station Quywged PO Toronto, London Ontario, a distributor of MicaFil
• Siscoe Vermiculite Mines Ltd., Cornwall Ontario, the mine site for this Vermiculite
• Munn and Steele Inc., South Boston Massachusetts, licensing the sale of the product in the U.S.

Our second illustration of MicaFil vermiculite insulation in original packaging, was provided courtesy of Michael Gou who posted this photo originally in a Q&A on this page.

(Aug 9, 2018) Michel Gou said: I insulated part of a wall with vermiculite in the 1980s. I have found a complete bag for which I enclose photos. Can you tell me if this particular brand was asbestos free or not. Thank you.

Reply:

From the packaging showing that Isolation Micafil Vermiculite Insulation was distributed from Montreal, London or Toronto, I suspect that you are located in Canada. There was asbestos in some vermiculite mined in Canada.

Please see details about this insulation (where I'll also add your photo) above on this page where I will include your photo and a request for comment from other readers.

I would treat the insulation as presumed to contain asbestos unless or until you have a sample tested.

See ASBESTOS TESTING LAB LIST

Reader follow-up:

From historical documents and I did see a Trademark infringement blurb in my search. I was as equally stumped in finding where their product could have been mined. I did locate another reference to a mas-Celo operation that was suspended in the late 30's and came back on line in the early 40's. From looking at pictures on line we have a lot of black colored substances that more mirror the micafil than the zonolite.

I was not able to locate any records denoting an affiliation with the WR Grace Libby mine or if the Grace zonolite mined and sent to the Hamilton refinery was ever sold to Munn for redistribution. Maybe I dodged a big one. My architect said it is not vermiculite but he took a sample to have it tested. I will keep you posted and we have ceased all work.

Reply:

Your architect is almost certainly mistaken - your photos show what is rather unmistakable vermiculite loose fill insulation.

But "vermiculite" does not necessarily mean "asbestos" as we've been discussing. Only a lab test can determine that question.

See WARNINGS BEFORE REMOVING VERMICULITE INSULATION

Westroc & Gold Nugget Vermiculite Insulation - related to MicaFil?

Westroc vermiculite could have originated at more than one location. However, research I cite below cites the Westroc mine in British Columbia (Canada). For that reason Westroc or Westrock and "gold nugget" vermiculite might indeed contain asbestos and may have been a Canadian product.

• Simandl, G.J., Irvine, M.L, Grieve, D., Lane R., Wojdak, P., Madu, B., Northcote, B. and Schroeter, T, "Review of Industrial Minerals in British Columbia, Canada - 2006", retrieved 2016/03/22, original source: www.empr.gov.bc.ca/mining/geoscience/publicationscatalogue/geofiles/documents/gf2007-08.pdf
• George J. Simandl and Angela M. Rossley - B. C. Geological Survey, Industrial Minerals: Current Trends and Future Opportunities, (2000) www.empr.gov.bc.ca/Mining/Geoscience/PublicationsCatalogue/InformationCirculars/Documents/IC2002-03_32-Simandl_Industrial_Minerals.pdf

The term "gold nugget" appears so widely in literature describing some forms of vermiculite that we are reluctant to ascribe that name to a specific mine or vermiculite brand without seeing actual packaging or other documentation.

The U.S. CDC describes "vermiculite" as "Expanded vermiculite is shaped like a small nugget and varies in color from silver-gold to gray-brown."

I have not yet found the specific term Gold Nugget Vermiculite as a specific vermiculite product brand name.

MicaFil Vermiculite Insulation Research & Information Sources

Below: another photo of MicaFil vermiculite insulation packaging from an anonymous reader - August 23, 2018.

If any readers have asbestos test lab results for this specific product please post those results at the bottom of this page.

• D.R. ASBESTOS TEST LAB RESULTS for a SAMPLE of Mica-Fill VERMICULITE [PDF] InspectApedia reader D.R., Pinchin Labs, Canada, 2024/01/04
  
  Watch out: while this report did not find asbestos in this MicaFil vermiculite sample you should note that MicaFil vermiculite sold in Canada may have been mined from various different sources.
• ATSDR, VERMICULITE CONSUMER PRODUCTS [PDF] U.S. CDC, Centers for Disease Control, retrieved 2018/08/09, original source: https://www.atsdr.cdc.gov/NEWS/vermiculite051603.pdf
• Canada, NWT, MANAGEMENT OF ASBESTOS IN ZONOLITE® - VERMICULITE INSULATION [PDF] Canadian Northwest Territories, Public Works & Services, PWS Asbestos Coordinator Technical Support Services Asset Management Division, Public Works and Services S.M. Hodgson Building, 3rd Floor Box 1320, Yellowknife, NT X1A 2L9 Tel: (867) 920-8835 or (867) 920-8088 Fax: (867) 873-0226 - retrieved 2023/12/27 original source: inf.gov.nt.ca/sites/inf/files/management_of_vermiculite_brochure.pdf
  
  NOTE that this article refers to Zonolinte vermiculite, not Munn & Steele MicaFil.

Above: details about Palabora Vermiculite from South Africa (Frank 2001) cited below. [Click to enlarge any image]

Special thank-you to reader D.R. for finding this research book on identifying the source mines for vermiculite. (2024-01-04)

• Frank, David, and Lorraine Edmond. FEASIBILITY FOR IDENTIFYING MINERALOGICAL AND GEOCHEMICAL TRACERS FOR VERMICULITE ORE DEPOSITS [PDF] US Environmental Protection Agency, Region 10, 2001. - retrieved 2024/01/05, original source: nepis.epa.gov/
• Health Canada, VERMICULITE INSULATION CONTAINING, AMPHIBOLE ASBESTOS [PDF], Health Canada, September 2009, web search Jan 2011, source hc-sc.gc.ca/hl-vs/iyh-vsv/prod/insulation-isolant-eng.php
  
  Quoting
  
  Some vermiculite insulation may contain amphibole asbestos fibres. These products can cause health risks if disturbed during maintenance, renovation or demolition. However, there is currently no evidence of risk to your health if the insulation is sealed behind wallboards and floorboards, isolated in an attic, or otherwise kept from exposure to the interior environment.
• [1] Intellectual Property Law of Canada - Second Edition, Stuart C. McCormack
• [2] Offners International Trademark Service, Vol. 6, Eric D Offner, 1970.
• [3] 48 Trademark Rep. 917 (1958) Recent Canadian Decisions; Fox, Harold G.
• [4] SISCOE VERMICULITE MINES LTD., V.I.L. VERMICULITE INC. 1775 -52nd Avenue Lachine H8T 2Y1 QUÉBEC produced vermiculite insulation from (at least ) 1959
  La propriété Siscoe Est est située à 3 km au nord-ouest de Val-d'Or, au Québec, près des anciennes mines Siscoe et Sullivan qui, ensemble, ont produit plus de 2,1 millions d'onces d'or entre les années 1930 et 1968.
  
  C'est aussi le site de l'ancienne mine Stabell qui a produit 1 750 onces d'or provenant de minerai titrant en moyenne 0,27 once d'or par tonne de 1935 à 1937.
  
  La propriété repose sur les roches volcaniques du Groupe de Malartic Inférieur vers le nord-ouest et sur une intrusion de granodiorite régionale connue sous le nom de batholite de Bourlamaque, vers le sud-est.
  
  En 2006, Alexandria a achevé une campagne de forage de 2 750 m et par la suite, Niogold a conclu une entente de coentreprise pour acquérir une participation de 50 % dans la propriété en 2008.
  
  Actuellement, Niogold est l'exploitant principal sur la propriété et a achevé un programme d'exploration à la fin de 2009. - see Alexandria Minerals at http://azx.ca/french/projects/siscoe/summary.html
• [5] Guillet, G.R., "Vermiculite in Ontario, With an Appendix on Perlite", Ontario Department of Mines, 1962, http://www.geologyontario.mndmf.gov.on.ca/mndmfiles/
  pub/data/imaging/IMR007/IMR007.pdf
• [6] Siscoe Vermiculite Mines Ltd. v. Munn & Steele Inc. (1957)
• [7] The Montreal Gazette - Mar 26, 1960
• [8] mining journal, http://vredenburgh.org/mining_history/pdf/AMJ-1940-pt1.pdf
• [9] North, Oliver S., & Jensen, Nan C., VERMICULITE [pDF] undated, approx, 1955, document from U. Wisconsin, images.library.wisc.edu/EcoNatRes/EFacs2/MineralsYearBk/MinYB1954v1/
  reference/econatres.minyb1954v1.onorth6.pdf
• Schundler, VERMICULITE MSDS [PDF] Schundler's vermiculite product Safety Data Sheet

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2024-01-05 by InspectApedia Publisher - MicaFil asbestos test lab report now online

@DR,

Readers can now see this MICAFIL VERMICULITE INSULATION ASBESTOS TEST LAB RESULTS for DR's sample of Mica-Fil Vermiculite Insulation in a Canadian home thanks to reader DR who sent it to us by private email.

On 2024-01-04 by InspectApedia DF (mod) - Some Mica-Fil tests find no asbestos!

@DR,

Some Mica-Fil tests find no asbestos!

Thank you so much for taking time to post that result here - it will certainly help other readers.

Indeed lots of vermiculite does not contain asbestos or doesn't contain more than very slight traces of asbestos. The asbestos hazard depends on where the vermiculite was mined. The Libby vermiculite mine was a principal source of asbestos-contaminated vermiculite.

Knowing the building age and location and thus having a guess at the Mica-Fil vermiculite age and source is also helpful.

On 2024-01-04 by InspectApedia DF (mod)

@DR,

Thank you for the packaging photos and for telling us the details of what the test showed.

If your lab report is in PDF form or .doc etc. then you'll need to use our page bottom CONTACT link to find our email and send the report that way; we can redact your personal information and convert that to an image file.

Comment box only allows readers to post images files such as .jpg, .img, .jpeg .gif, etc.

On 2024-01-04 by DR

This is an image of MicaFil vermiculite.

On 2024-01-04 by DR - Micafil vermiculite insulation from South Africa shows no asbestos in test results

Hello, we found Mica-Fil bags and vermiculite in our attic this fall. We had it tested. I have attached pictures, and the lab report.

I am happy to report that in our case, the lab did not find any asbestos, and determined the vermiculite was consistent with analysis and visual appearance from a mine in South Africa, which is not known to contain naturally occurring asbestos.

On 2023-12-10 by InspectApedia Publisher - 1960 New Brunswick, Canada home with MicaFil vermiculite insulation

@Shelby,

Thank you for the helpful Mica-Fil vermiculite photos and question.

I looked at your photos to see if there was mention of which mine was the source of that particular vermiculite - without seeing that detail. When we don't know which mine was the source, without sophisticated testing we can't know for sure just what vermiculite mine sources were used when by various vermiculite insulation marketing companies as the principals are too-long gone to ask.

Above on this page I reported (I've edited that a bit here) that

My search for records indicating whether or not Munn & Steele / Mica-Fil actually sold vermiculite that came from the Libby mine (or from the Siscoe mine)

did not find any indicators suggesting a yes or no answer

but it seems certainly possible, since some of the MicaFil packaging that we've seen specifically names the Siscoe vermiculite mine.

So I'd avoid tracking the dust from your insulation into the occupied space, and please do let us know your test result - that will be very helpful to others.

Finally, if you can post sharp photos of any other printing on the MicaFil bag that we can't quite see here that would be helpful as well.

On 2023-12-10 by Shelby

Hello, we have an attic full of vermiculite Micafil Insulation. It is made in Canada. Our home was built in 1960 in New Brunswick, Canada.

We are planning to get it tested, but do you have any insight into whether or not this would contain asbestos?

 

On 2023-07-09 by InspectApedia DF (mod) - Not all vermiculite sources contain asbestos

@milan,

You're on the right page for our discussion on Mica Fil vermiculite insulation.

Can you post a photo of the back of this packaging as well? It would be helpful to see what added information, if any, is included there.

Interestingly on their website, in discussing their history, California Stucco Products makes no mention of producing or selling MicaFil vermiculite insulation in the past.

Obviously, your packaging shows that they did at one time. Perhaps not surprising, given the concerns over potentially asbestos-containing products (this is NOT to say that their products contained asbestos), that they don’t choose to advertise this piece of their past.

Not all vermiculite sources contain asbestos. One cannot determine asbestos content in vermiculite by normal visual inspection.

I would treat the insulation as presumed to contain asbestos unless you have a sample tested and find out differently.

Thank you for the photo.

On 2023-07-08 by milan

Found this in my attic, home is built in 1959 outside Boston, MA. Not sure when it was poured. Anyone know any details on where it was mined and if it may have asbestos?

On 2022-01-11 by Danjoefriedman (mod)

@Bren,

Assuming your question is about MicaFil insulation, not the batt that contained it,

Please do take a look at the article above on this page as it's what we've been able to find by research on your question.

On 2022-01-11 by Bren

Did anyone ever confirm if the orange Micafil bag contained asbestos?

...

Continue reading at VERMICULITE INSULATION INCIDENTAL EXPOSURE HAZARDS ? or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see MUNN & STEELE VERMICULITE, MICA-FIL FAQs - questions & answers posted originally at this page.

Or see these

Recommended Articles

• ASBESTOS STYROFOAM PANELS
• ASBESTOS TESTING LAB LIST
• INSULATION IDENTIFICATION GUIDE
• VERMICULITE INSULATION - home
• HOW TO IDENTIFY VERMICULITE INSULATION - separate article
• VERMICULITE HISTORY & PROPERTIES
• WHAT TO DO ABOUT VERMICULITE INSULATION
• ZONOLITE BRAND VERMIULITE INSULATION ZAI & CLAIMS
• MUNN & STEELE VERMICULITE, MICA-FIL, Siscoe Vermiculite Mine
• VERMICULITE INSULATION INCIDENTAL EXPOSURE HAZARDS ?

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