resolving the vermiculite asbestos conflict · 2014-12-01 · new methods will be capable of...

Resolving the Vermiculite Asbestos Conflict “A New Approach to Detection and Quantitation”

The Vermiculite Association: Annual Meeting Park City, Utah

(September 11-13, 2014)

Don Ewert; Industrial Hygienist – Occupational Health Services

35 Years as a Practicing Industrial Hygienist

Education in Industrial Hygiene, Toxicology, Biochemistry, Business Administration

Career Work in Chronic Toxins (High Energy Rad, Asbestos, CrVI, Parenteral Oncology, Nanomaterials

Creation of the first EPA-NIST/NBS Certified Mobile Laboratory for On-Site OEHS Assessments

Co-Author of Major OSHA and EPA Laws Involving Industrial Hygiene & Environmental Sampling

20 Years as an Expert Witness in the Field of Forensic Toxicology (Post-Injury Analysis)

Research Scholar - Center for Environmental Toxicology & Technology at CO State University

Past-Chair; AIHA Nanotechnology Working Group Full Member – Society of Toxicology

RJ Lee Group Resolving the Vermiculite Asbestos Conflict 2


AIHA Webinar - Wednesday, May 7, 2014 By: Andrey Korchevskiy, Eric Rasmuson, and James Rasmuson. The Synergist – Edition 2, 2014

Asbestos

• Occurs naturally in rock and soil, including the regulated forms of chrysotile, amosite, crocidolite, tremolite, and anthophyllite asbestiform minerals.

• All asbestos minerals have demonstrated an ability to produce cancer in animals as well as humans. In fact, asbestos is one of only a few known carcinogens regulated by USOSHA.

• Asbestos use in the United States is limited as a result of laws passed in the 70’s and 80’s while it remains actively produced and used in other portions of the world.

Asbestos – A Summary Refresher


Asbestos – Two Distinct Mineral Groups

Serpentine Fibers – Represented by chrysotile

•Cleared quickly from the human lung •Low in iron concentration •Distinct morphology •Airborne fibers are often agglomerated

Amphibole Fibers – Represented by amosite, crocidolite, tremolite, and anthophyllite

•Biopersistent – exceptionally long half-life •Moderately high iron concentration •Straight fiber bundles capability of defoliation •Airborne fibers don‘t agglomerate


• Asbestos in buildings remains an ongoing abatement expense

• Naturally occurring asbestos (NOA) is becoming a new concern Construction Mining Libby Amphiboles

• Asbestos is still actively being mined and used In the former Soviet countries, up of 90% of roof materials are ACM

• Improved analytical methods has led to updated epidemiological results Focus on low level exposure affects

• Impact of asbestos-like physiological behavior on emerging materials Zeolites Nanomaterials (CNT’s) Man-made fibers (macroscale ceramic, polymeric, etc)

Asbestos – Still a Concern


Cancer Experience by Mineral Group


Risk Assessment Models – Development History


Risk Assessment Models – Low Dose Case Studies


Asbestos Risk - Model Uncertainties


Model Comparison – Excess Cancer Cases/Million

(0.1 f/cc, 45 years starting at 18)


International View on Asbestos Regulation

• European Union standard = 0.1 f/cc

• Health Council of the Netherlands proposals for asbestos: Amphiboles = 0.00025 f/cc Mixed Species = 0.0013 f/cc Chrysotile = 0.002 f/cc

• Germany; instead of occupational exposure limits for asbestos, requirements exist for protective measures depending upon airborne fiber concentration (e.g. PPE can be waived if concentration <0.0015 f/cc)

• Russia has extremely cumbersome regulation Occupational exposure regulated as a dust in mg/m3 based on an assumed

fiber content. Different standards for chrysotile and amphiboles (200 fold) Ambient standard of 0.06 f/cc by PCM, 0.08 mg/m3 total dust having an

asbestos content of >20%.


Discovery of Copper 1895 - 1905

Chronology of Rainy Creek and Libby Vermiculite

The Rainy Creek sub-district encompasses a small area northeast of Libby in the Rainy Creek drainage. Prospectors located isolated copper deposits there in the late 1890s and early 1900s. John L. Neihart, of the mining town of Neihart, caused considerable excitement when he examined these deposits and predicted that they would make the Rainy Creek district "another Butte in the production of copper" (Renk 1994). Copper mining never developed much beyond the stage of wishful thinking, but the Rainy Creek district became well-known for a very unassuming mineral called vermiculite. Mica particles heated expands up to 15 times their original size. The end product is vermiculite, which is used primarily in fireproofing and insulation from heat, cold, and sound (Renk 1994; Perry 1948).

Vermiculite Discovered 1905 - 1915

Large deposits of vermiculite and small metallic deposits in the Rainy Creek sub-district are found in a stock of alkaline rocks that intrudes into the Proterozoic rocks of the Belt series. Two-thirds of the stock is coarse-grained pyroxenite, from which vermiculite is derived, and one-third is coarse-grained syenite. Hydrothermal alteration has caused major changes in the stock, producing white mica, aegirite and aegirite-diopside, vermiculite, and fibrous amphiboles (Pardee and Larsen 1929).

Zonolite is Created 1915 - 1991

Edward N. Alley discovered the vermiculite deposits during World War I when he was prospecting for vanadium. He experimented with samples, built a small kiln to process the ore, and promoted the material under the trade name of Zonolite. This led to a demonstration plant in 1924, followed two years later by a larger facility capable of processing 100 tons of ore each day. Alley sold his interests in 1934, leaving two different companies working the deposits on Rainy Creek. They merged in 1939 to form Universal Zonolite Insulation Co., altering the name to the Zonolite Co. in 1948. The business came under the control of W. R. Grace and Co. in 1963 and continued operations until 1991 (Renk 1994).

65-Year Legacy 1925 - 1990

Operators mined most of the vermiculite ore through large open cuts; several adits, one 750 feet long, also provided access to the ore. Initial processing took place at a concentrator near the mine. Trucks then hauled the concentrate to the Libby plant for heating and expansion into the final product. Some of the concentrates were shipped to plants in Great Falls, other states, Canada, and other foreign countries for final processing there. About 1940, Universal Zonolite mined 500 tons of ore each day, reducing it to 200 tons of concentrates. Twenty-four years later, the company turned out 2400 tons of ore each day, reducing this amount to 500 tons of concentrates. There are no figures for total production since this information was restricted after 1930 (Perry 1948; Johns 1970; WPA 1941).


New York State law modified to designate “vermiculite insulation” as “Suspect Miscellaneous ACM” that must be treated as ACM unless proven otherwise by approved laboratory testing.

3/21/07

New York State DOH guidance FAQ #10 recommends that with no approved analytical methodology to reliably confirm vermiculite as non-asbestos containing, it is always best to assume that vermiculite is contaminated with asbestos and proceed accordingly.

4/8/11 6/22/12

New York State DOH guidance FAQ #10 states that wherever SOF-V is calculated to be >10% vermiculite containing, the material must be reported as ACM.

8/27/12

New York State DOH guidance FAQ #10 states that wherever SOF-V is calculated to be >10% vermiculite containing, Item 198.6 may be used to evaluate the asbestos content of the material; provided, however, that any test results using this method must be reported with the following conspicuous disclaimer:

“This method does not remove vermiculite and may underestimate the level of asbestos present in a sample containing greater than 10% vermiculite.”

7/9/13

New York State DOH interpretation of vermiculite-related guidance does not prohibit the use or application of vermiculite materials, but instead applies during renovation and/or demolishing of structures when the origin of the vermiculite material is unknown.

New York State DOH announces the imminent availability of two new NYS DOH ELAP-approved methods for the detection and quantitation of asbestos content in spray-on fireproofing that contains vermiculite (SOF-V).

7/22/14 7/24/14

New York State DOH notifies RJ Lee Group that validation for LAB.055.1 has met the conditions set forth in 10NYCRR 55-2.5 and is fully certified for SOF-V testing.

Chronology of NY DOH Guidance on Vermiculite

8/20/14

New York DOH introduces publicly available Item 198.8, a modified Chatfield Method for the analysis of asbestos in Spray-On Fireproofing containing Vermiculite (SOF- V) by Polarized-Light Microscopy (PLM).

Regulated Asbestos - The EPA definition of 'asbestos' includes six asbestos minerals: chrysotile, amosite, crocidolite, tremolite asbestos, anthophyllite asbestos, actinolite asbestos, 29 CFR 1910.1001(b), definitions. The state of New York regulates asbestos by the same standard.

According to the US EPA, materials containing greater than 1 percent (>1%) asbestos are regulated as asbestos containing materials (ACM).

Vermiculite Study - Definitions



Non-Regulated Amphibole Asbestos (e.g., winchite/ richterite) - Reported when the morphological characteristics of the amphibole are consistent with asbestos. However, it is not used in determining whether a material is ACM.

While winchite and richterite amphiboles are non-regulated forms of asbestos, they exhibit some of the same characteristics as regulated asbestos. As a result, they are often misreported as asbestos because of the fact that their characteristics are consistent with asbestiform minerals.


Spray-On Fireproofing containing Vermiculite (SOF-V) - SOF-V is defined as a material containing vermiculite, intended to act as a fire-retardant coating when applied to building structures via spraying equipment as opposed to a manually applied (trowel) material. SOF-V can be in the form of Thermal Systems Insulation (TSI), surfacing material, or other presumed ACM (PACM). No matter the form, it is a miscellaneous suspect ACM as specified in 12 NYCRR Part 56 which include, but are not limited to, existing or new surfacing material, plaster, pipe lagging, and spray-on fireproofing.




Testing Requirements for Sprayed-on Fireproofing Containing Vermiculite (SOF-V)

This communication is in follow up to the July 9, 2013 interim guidance letter regarding testing alternatives for materials containing vermiculite, issued by the New York State Department of Health (NYS DOH), in collaboration with the New York State Department of Labor (NYS DOL).

The enclosed communication announces the imminent availability of two new NYS DOH ELAP-approved methods for the detection and quantitation of asbestos content in spray-on fireproofing that contains vermiculite (SOF-V). The testing strategies for SOF-V outlined in the July 9, 2013 interim guidance letter may be used until October 31, 2014. After October 31, 2014, one of the new methods must be used to test SOF-V, regardless of the percent of vermiculite. Since the new methods will be capable of removing vermiculite content, they are the only results for SOF-V that may generate a Non-ACM result without the need for the disclaimer required in the July 9, 2013 interim guidance letter.


The following is a brief description of how and when these new methods must be utilized for analytical testing; please also refer to the enclosed Decision Tree for more guidance.

· In the field, when an inspector, using his/her professional judgment, determines that a sprayed-on fireproofing (SOF) may contain vermiculite, the material may be presumed ACM according to 12 NYCRR Part 56 (NYS Industrial Code Rule 56), or they must forward that material to a NYS DOH ELAP certified laboratory for analysis. Since all NYS approved PLM methods begin with a stereoscopic examination of the material, this stereoscopic examination can confirm the presence or absence of vermiculite. If vermiculite is present (regardless of the amount), one of the two new approved methods must be used for the detection and quantitation of asbestos content. If vermiculite is not present, then Items 198.1 or 198.6 must be used, as appropriate, and based upon the presence of organically-bound or microscopically interfering materials.


The following is a brief description of how and when these new methods must be utilized for analytical testing; please also refer to the enclosed Decision Tree for more guidance.

· In the field, when an inspector, using his/her professional judgment, can not make the determination if the (SOF) contains vermiculite, the material may be presumed ACM or sent to a laboratory certified for Items 198.1, 198.6, or one of the two new approved methods. If vermiculite is determined to be present at any concentration during the stereoscopic examination required in all NYS PLM approved methods, then the material must be further analyzed by one of the two new approved methods. If vermiculite is not present, then Items 198.1 or 198.6 must be used, as appropriate, and based upon the presence of organically-bound or microscopically interfering materials.


Industry Implications: The approval of these new methods for the identification and quantitation of asbestos in SOF-V will have the following implications during the demolition, renovation, remodeling and/or repair of buildings that fall under the authority of NYS Industrial Code Rule 56.

· For future projects that have no associated survey – MUST use one of the new methods and current NYS guidance.

· For projects that have an existing survey, but no project plan – MUST resample and resurvey and use one of the new methods and current NYS guidance prior to starting any new project.

· For projects with an existing survey, and project yet to be done (Phase 1A) – MUST resample and resurvey and use one of the new methods and current NYS guidance.


Industry Implications: The approval of these new methods for the identification and quantitation of asbestos in SOF-V will have the following implications during the demolition, renovation, remodeling and/or repair of buildings that fall under the authority of NYS Industrial Code Rule 56.

· For projects in progress using an old survey, and work actively underway (Phase 2A-2D) – re-sampling and use one of the new methods is RECOMMENDED, but NOT REQUIRED – UNLESS – there is a change to the project design requiring a change order. If a change order is required, then re-sampling and analysis by one of the new methods and current NYS guidance is REQUIRED on the new area.

· For completed projects that were conducted under an old survey – there is no requirement to go back and re-sample. However, if there is a need to disturb a material in the future - MUST use one of the new methods and current NYS guidance.

An Analytical Solution is Developed


COMPREHENSIVE TEST APPROVAL POLICY AND SUBMISSION GUIDELINES

Subsection 58-1.10(g) of Part 58 of Title 10 (Health) of the Official Compilation of Codes, Rules and Regulations of the State of New York states that all technical procedures employed in a laboratory shall be of proven reliability and generally accepted by leading authorities in the specialties of laboratory medicine and/or approved by the Department. A laboratory can perform only those assays for which the performance characteristics have been established and validated, or if already established (typically by a manufacturer) verified at the site where the assay will be performed. The laboratory must also hold the appropriate permit category for the test and must meet all other requirements related to on-site survey, personnel and proficiency testing.



Hitachi HD-2300 STEM Cutting Edge Technology

RJLG utilizes innovative technology for

unprecedented materials characterization abilities.

Hitachi S-5500

SEM/STEM

RJ Lee Group Instrumentation

1st Mira

delivered

to EPA


• Microscopy

– Optical Microscopes

– Scanning electron microscopes

– Transmission electron microscopes

– High resolution electron microscopes

– Computer-controlled microscopy

• Surface Analysis: ESCA/XPS

• X-ray Diffraction

• X-ray Fluorescence

• Fourier Transform Infrared Spectroscopy

• Raman Imaging & Spectroscopy

• Analytical Chemistry

– ICP-ES and ICP-MS

– AA and IC

– GC-MS, GC-FID, GC-ECD

– DSC / TGA

RJ Lee Group Instrumentation

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Thermo K-Alpha XPS

Vermiculite Method Introduction

• RJ Lee Group Response (18 Month Process)

– Develop a Method

• Paid in part by New York Major Property Manager

– Seek NY DOH Approval

• Provided Proof of Concept Study

• Drafted Method for Single Laboratory Approval

• Submitted Method and Met with DOH Repeatedly

• NY DOH Review

– Requested a complete method validation study


Vermiculite Study Design – Challenges

• Current methods may underreport asbestos content & generally don’t report or speciate naturally occurring asbestos

• Other methods, incorporating processes for physical separation of materials are subject to significant inter-laboratory variability – Methods were designed for bulk vermiculite with minimal binding

materials.

– Use of PLM & TEM is known to be highly variable at low concentrations.

– Much and most often amphibole materials are tied up within “sheets” of the vermiculite matrix.

• Most laboratories have limited mineralogical expertise in differentiating between asbestos and non-asbestos amphiboles


Vermiculite Study Design – Solution

• Take advantage of common materials used in vermiculite fireproofing

– vermiculite, cellulose, carbonates, gypsum, cement, and fiberglass

• Selectively eliminate these materials to reveal materials of concern

RJLG Method Sample Prep Features Benefits to Material Screening

Level 1 (PLM) Removes gypsum, carbonates, and cellulose to making vermiculite content quantifiable.

Removes speculation about vermiculite content of the material (> or <10%). Avoid unnecessary abatement.

Level 2 (PLM & SEM) Removes vermiculite, fiberglass, and other soluble material in order to clearly quantify asbestos.

Fast and unambiguous results to determine asbestos content (> or <1%). Creates a digital record of SEM results for later reference.


Steps and Actions in RJLG Vermiculite-Containing Fireproofing Analysis

*Reported analysis results include quantitation of non-regulated asbestos species. These amphiboles are not considered in determining final outcomes.

Vermiculite Study Design – Solution


RJLG Analysis Levels Steps and Actions in SOF-V Analysis

Regulated Asbestos* Outcome/Action

RJLG Level I: Water/acid wash to remove gypsum and carbonates, then ash to remove cellulose

>2.0% Chrysotile

ACM

≥0.5% and ≤2.0% Chrysotile

Repeat Level I analysis at least

two more times (n≥3)—If arithmetic mean result is >1%,

report as ACM

If arithmetic mean of repeated

results is ≤1%, proceed to

RJLG Level II

RJLG Level II: Ash, then aggressive acid base digestion to

dissolve vermiculite and other soluble materials

Regulated Amphibole Asbestos >1%,

ACM

Regulated Amphibole Asbestos ≤1%

Report regulated amphibole

asbestos

Reporting Sum of Level I and Level II regulated

Asbestos >1% ACM


Method Description - LAB.055.1

RJ Lee Group Method LAB.055.1 is a two tier analytical process wherein Level I is restricted to the detection and quantitation of chrysotile. During Level I preparation, the raw material is ashed and washed using water and hydrochloric acid (HCl) to remove residual moisture along with any acid soluble materials including cellulose that may interfere with analysis. Thereafter, the improved visibility allows PLM analysis to be used for accurately identifying and quantifying the chrysotile concentration that exists.


Method Description - LAB.055.1

Level II analysis is used to accurately detect and quantify the amount of amphibole asbestos. The process involves ashing to remove carbonate, gypsum, cellulose, and fiberglass followed by digestion with concentrated acid/base solutions to dissolve the vermiculite. Once the interfering materials are abated, Level II employs a combination of PLM and SEM to detect, speciate, and quantify the amphibole asbestos content that exists.

X = arithmetic mean

VC-SOF Sample

Level I Treatment Chrysotile Analysis (400 Point Count)

Level II Treatment Amphibole Analysis

(PLM / SEM)

If >2.0% Chrysotile

If ≥0.5% - ≤2.0% Chrysotile

If <0.5% Chrysotile

Report As ACM

Triplicate Analysis With Averaging of

Results

If X >1.0% If X ≤1.0%

Proceed to Level II

Report As ACM

Proceed to Level II

If >1.0% Regulated Amphibole

Report As ACM

Sum the Results of Level I and Level II

(Regulated Asbestos)

If <1.0% Regulated Amphibole

If X >1.0% If X ≤1.0%

Report As Non-ACM

Reporting Differentiates Regulated and Non-Regulated Amphibole Content


LAB.055.1 Process

Samples Before and After Matrix Reduction

RJLG Level II

(Left) Light microscopy image of bulk vermiculite material and (right) scanning electron microscopy (SEM) image of Level II matrix reduction to remove vermiculite and other interfering materials leaving behind any amphiboles (circled).


Vermiculite Study Design – Validation

• Over 1000 tests performed

• Spiked, 5.0-gram samples of vermiculite fireproofing

– 5, 2, 0.5, 0.1, and 0.02 percent of each regulated amphibole type and chrysotile.

• Direct comparison of NY DOH 198.1 and 198.6 methods with RJLG Level 1 and 2 analysis



Vermiculite Analysis - Reporting

Chrysotile Samples 198.1 vs. 198.6


Amphibole Samples 198.6 vs. RJLG Level 2


Precision and Accuracy of RJLG Level 2



LAB.055.1 – Performance Summary

Overall, the effectiveness of the Level I procedure in detecting Chrysotile as a means of defining whether a sample should be treated as asbestos containing material (ACM), i.e. whether chrysotile is present at a concentration >1%, is 69%, compared with a 57% detection rate using the NYS DOH 198.6 method. The Level II amphibole procedure has been shown to be more than 90% accurate in determining whether SOF-V is ACM, compared with a 59% effectiveness rate using NYS DOH method 198.6. Furthermore, Level II was found to be 100% reliable in identifying non-regulated amphibole asbestos whereas, NYS DOH 198.6 only showed a 5% effectiveness rate in detecting non-regulated amphibole species.


From: Stephanie E Ostrowski [mailto:[email protected]] On Behalf Of ELAP BML Sent: Wednesday, August 20, 2014 8:43 AM Cc: ELAP BML Subject: Update!! - NYS DOH Asbestos Methods revised & DOH Method for SOF containing Vermiculite NOTE: These are several changes to all of the DOH- approved asbestos methods in the Solid and Hazardous Waste category. Please read the following email carefully. ELAP is announcing the availability of “Item 198.8 of Manual” (ELAP code 4601) entitled: “Polarized-Light Microscopy Method for Identifying and Quantitating Asbestos in Sprayed-On Fireproofing Containing Vermiculite Bulk Samples” http://www.wadsworth.org/labcert/elapcert/certmanual/index.html Please also refer to the Department of Health's recent guidance entitled “Testing Requirements for Sprayed-on Fireproofing Containing Vermiculite (SOF-V)” dated July 22, 2014. http://www.wadsworth.org/labcert/elapcert/forms/NewTestingRequirements_SOF_072214.pdf

+

mailto:[email protected]

http://www.wadsworth.org/labcert/elapcert/certmanual/index.html

http://www.wadsworth.org/labcert/elapcert/forms/NewTestingRequirements_SOF_072214.pdf

http://www.wadsworth.org/labcert/elapcert/forms/NewTestingRequirements_SOF_072214.pdf


Method Description - NY DOH 198.8

Item 198.8 incorporates a two-step approach for the identification and quantitation of chrysotile and amphibole asbestos, including Libby amphiboles, in SOF-V. The first step utilizes gravimetric reduction including ashing to remove the organic materials and dilute acid treatment to remove gypsum and cement from SOF-V. The residue is then examined by PLM for the presence of chrysotile, which is quantitated by point counting. If the concentration of chrysotile is found to exceed 1%, the material is considered asbestos containing material (ACM) and the analysis is terminated. If chrysotile is either not detected, or is found at a concentration less than 1%, then the analysis is continued to determine the concentration of amphibole asbestos.


Method Description - NY DOH 198.8

Heavy liquid centrifugation is used to separate particles with densities exceeding 2.75 g/cc from the majority of the less dense matrix components. This results in a centrifugate that contains any amphibole that was present in the original sample. The concentration of the remaining amphibole is determined by PLM and point counting. The total asbestos content is obtained by adding the concentration of asbestos quantitated in step one (chrysotile) with the asbestos quantitated in step two (amphibole). If the final concentration is determined to be greater than 1%, the material is designated as ACM.


Ash for 10 hours

Acid Treatment

Filter Suspension

Chrysotile Analysis

If >1.0% Chrysotile

Report As ACM

If <0.5% Chrysotile

Proceed to Centrifugation

1st Centrifugation

Remove Vermiculite

Disperse Centrifugate

2nd Centrifugation

Aspirate Centrifugate

Amphibole Analysis (PLM Only)

If >1.0% Amphibole

If <1.0% Amphibole

Sum the Results Total Asbestos

If X ≤1.0% Report As Non-ACM

Report As ACM

If X >1.0%

VC-SOF Sample

198.8 Process

Method Comparison


Detail LAB.055.1 198.8

Vermiculite-Amphibole Separation Method

Chemical Physical

Microscopy Method SEM / PLM PLM Only

Differentiation of Naturally Occurring Amphiboles

Yes No

Analysis Pricing 18 Hour Process - $400 15-20 Hour Process - $?

Number of Contact and Transfer Processes

<5 >10

Round Robin (Zonolite vs Spiked Samples)

TBD TBD

Conclusions

The RJLG method:

• Provides sound data based on chemical separation and SEM analysis of the material (results are definitive).

• Reliably determines whether a product is ACM at the 1.0% level (NY DOH Limit)

• Accurately quantifies all amphibole types down to 0.01 percent.


54 An Industrial Forensic Approach RJ Lee Group

Donald Ewert, IH [email protected]

724-387-1856

Contact Information

We thank the professionals and staff of RJ Lee Group who contributed to the success of this endeavor.

RJLG also wants to recognize the dedicated efforts of the New York Department of Health during development and approval of method LAB.055.1

resolving the vermiculite asbestos conflict · 2014-12-01 · new methods will be capable of...

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