Beryllium Exposure Assessment: Review of Sampling and

Analytical Developments and Impending U.S. Regulatory

Changes

Michael J. Brisson, Savannah River National Laboratory, Aiken, SC, USA

Gary E. Whitney, Los Alamos National Laboratory, Los Alamos, NM, USA

Kevin Ashley, Centers for Disease Control and Prevention, National Institute for Occupational

Safety and Health, Cincinnati, OH, USA

Chemical Risk: Innovative Methods and Techniques

9 April 2015, Nancy, France

SRNL-MS-2014-00162-S

Disclaimers

• The findings and conclusions in this presentation are those of the authors and do not necessarily reflect the views of DOE, SRNL, LANL, or CDC/NIOSH

• Mention of commercial products or companies does not imply endorsement or criticism.

• Nothing in this presentation is intended, nor should it be construed, to represent restraint of trade.construed, to represent restraint of trade.

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Beryllium Properties

• Light weight

• High melting point (1287 oC)

• High heat capacity

• Neutron reflector

• Relatively transparent to X-rays

• “High-fired” BeO:

Thermally conductive

Electrical insulator

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SEM of calcined BeO particles, by J. Fernback

(from Goldcamp et al., JOEH 2009)

Uses for Beryllium Products

• Satellites / spacecraft

• Guidance systems (military & commercial)

• Brake parts (automotive, aircraft)

• Nuclear weapons (neutron reflector)

• X-ray windows

• Optical instruments

• High-end audio• High-end audio

• Sports equipment

• Alloys (Al-Be, Cu-Be) resistant to corrosion

and/or metal fatigue

• Electronics micro-circuitry

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(CuBe alloy; http://materion.com)

Risks from Beryllium Exposure

Exposure to particles of beryllium metal, alloys, and oxide can lead to:

• Beryllium Sensitization (BeS)– Immune system response in percentage of

those exposed

– Detected by Be Lymphocyte Proliferation

Test (BeLPT)

• Chronic Beryllium Disease (CBD)– Percentage of sensitized individuals

– Particles lodged in lung, cannot be

expelled

– Causes lesions (granulomas)

– Medically diagnosed (bronchioalveolar lavage)

– Treatable but not curable

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(schematic from G. Day et al., 2007)

Current Occupational Exposure Limits

2.0(Current

OSHA PEL

– used by

11 other

countries)

0.2

(DOE AL;

also Cal-

OSHA,

Poland,

Spain-INH)

1.0

(Denmark,

Latvia)

0.15

(Quebec)

0.05

(ACGIH

TLV®,

inhalable

fraction)

Zero(everyone

wants it but

lab can’t

measure it)

0.5

(NIOSH

REL)

(Values in micrograms per cubic meter)

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OSHA – U.S. Occupational Safety and Health Administration

PEL – Permissible Exposure Limit

NIOSH – U.S. National Institute for Occupational Safety and Health

REL – Recommended Exposure Limit

AL – Action Level

INH – Inhalable Fraction

TLV – Threshold Limit Value

DOE also has a surface contamination limit (0.2 µg per 100 cm2)

Germany has been studying its

Be OEL, which may be reduced

(Nies, 2012).

Potential Changes to U.S. Regulations

• OSHA Permissible Exposure Limit– Expected: lower PEL, short-term exposure limit (STEL), housekeeping and PPE

requirements– Considered current DOE regulation & stakeholder input– Notice of Proposed Rulemaking expected soon (this year)

• DOE Chronic Beryllium Disease Prevention Program (10 CFR 850)– Currently uses OSHA PEL and is expected to continue doing so– Some aspects of OSHA regulation (such as STEL) do not currently apply; this might

change under new DOE proposal– Airborne OEL may be lowered significantly, perhaps to ACGIH TLV– Notice of Proposed Rulemaking not likely before late 2015– Notice of Proposed Rulemaking not likely before late 2015

• Potential Impacts– Some U.S. industries outside of DOE will need to take steps to reduce airborne Be– In DOE, the same may be true at some locations since oversight typically requires

adherence to levels below OSHA PEL– Labs likely to need ICP-MS or fluorescence, especially for short-term samples, because

ICP-AES may not offer sufficient detection limits– Other impacts to be determined when new proposed regulations are published

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Short-term air monitoring

Sampling considerations:

– For a 15-minute task, a 2 L/min pump provides 30 L or 0.03 m3

– In this case, lab must be able to detect 3% of the exposure limit

– If proposed OSHA STEL is used, this would be 2 µg/m3 x 3% = 0.06 µg per sample

Analytical considerations:

– Ideally MDL is a factor of ten below OEL to assure that measured result, including

analytical uncertainty, is quantifiable at the OEL

– Analytical method should provide MDL of 0.006 µg per sample or less

� High-flow sampler could help to ameliorate these constraints

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Sampling for Inhalable Fraction

• ACGIH TLV specifies inhalable fraction

• Current IOM inhalable sampler not disposable– Higher cost than disposable closed-face cassettes

– Requires cleaning between uses (time consuming and costly)

� Insert capsules for IOM under development

• Study to develop disposable sampler to collect inhalable fraction

(Volckens, Sleeth & Anthony, Airmon 2014)

� Goal: low-cost personal samplers for inhalable aerosols

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IOM-style Inlet

Capsule filter

CFC-style cartridge

Combine attributes of the CFC with the IOM Inhalable Aerosol Sampler

(courtesy of Profs. J. Volckens, D. Sleeth & R. Anthony)

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Want a sampling apparatus that is:

� Inexpensive

� Disposable

� User friendly

� Physiologically relevant

Sampler inserts (to account for wall deposits)

• Polyvinyl chloride (PVC) insert with PVC filter in a 37-mm CFC– Commercially available

– Suitable for gravimetric analysis

– Not appropriate for elemental analysis

• Acid-soluble cellulose acetate insert with mixed cellulose acetate (MCE) filter– Commercially available

Solu-Cap insert: skcinc.com

– Commercially available

– Incorporated improvements suggested by Ashley and Harper (2012, 2013)

– Not appropriate for gravimetric analysis due to mass variability with humidity changes

�NIOSH studies have validated gravimetric and elemental analysis using cassette inserts

�Inserts for IOM samplers also available soon

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Solu-Sert inserts: zefon.com

Analytical Advancements

• Fluorescence Method (McCleskey et al., 2005; Agrawal et al.,

2006; Ashley et al., 2007; Ashley, 2011)

• Interlaboratory Evaluation of ICP-MS (Ashley et al., 2009, 2012)

• Beryllium Dissolution Studies (Goldcamp et al., 2009; Oatts et

al., 2012)

N OH

SO 3H

HBQS fluorophore

• Direct-measurement techniques (e.g., LIBS)

�Fluorescence and ICP-MS methods yield MDLs in sub-ng per

sample range; also consider ETAAS

�Refractory BeO sample prep info used for methods updates

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ICP-MS plasma

Fluorescence Method for Ultra-trace Beryllium Measurement

1.

2.

6. Be

Addition of dye soln.

Sample

Automated high-throughput system

(Courtesy of Dr. A. Agrawal, Berylliant, Inc.)

3.

4.

5.6. Be

extraction

Fluorescence detection

FiltrationRemoval of aliquot

Automated high-throughput system

BeFinder Portable Fluorometer

Be dissolution studies (Oatts et al., 2012; Ashley et al., 2007; Goldcamp et al., 2009)

• Tested a variety of dissolution methods involving combinations of acids (e.g., HF, H2SO4, HCl, HNO3, HCl04, NH4HF2)

• Focused on dissolution of BeO as refractory compound typically seen by IH labs

• Concluded that fluoride or sulfate ions required for effective BeO dissolution

Individual lab recoveries ± std. devs.

125%

150%

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From Oatts et al., J.

Environ. Monit. (2012)

0%

25%

50%

75%

100%

125%

1007

1011

1005

1009

1013

1020

1004

1036

1012

1023

1029

1001

1003

1010

1017

1022

1025

1028

1016

1008

1033

1006

1024

1026

1027

1015

1018

1035

1002

1014

1019

1021

1030

1032

Lab ID #

Rec

over

y (%

)

H2SO4 groupHF group

NH4HF2 group

HNO3 group

Dermal Be Exposure and Sampling

• Potential risk from dermal exposure known for some time (Day et al., 2006)

• Nicas et al. (2008) indicated that:– Workers made hand to face content an average of 16 times per hour (but variable, ranging

from 1 to 35 contacts per hour)

– Contamination on the hands may be a point source for inhalation exposure when the hands are moved to the face.

• Whitney (2014) suggested that:– Hand to face contact may contribute significantly to inhalation exposure and deserves

further investigation.

– Gloves may protect skin, but may actually increase risk of contamination spread:– Gloves may protect skin, but may actually increase risk of contamination spread:• Workers feel protected, so they may be less cautious about handling contaminated materials.

• Some loss of dexterity and tactical sensation may result in clumsier hand movements that spread contamination.

– Sampling the surface of gloves/hands at various points in an operation may aid in identifying sources of contamination spread & exposure routes.

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Summary

• Recent sampling advances have focused on low-cost inhalable sampling and CFC inserts to reduce wall deposits– CFC inserts are commercially available

– Soluble inserts also available soon for inhalable (IOM) samplers

• Beryllium-specific analytical advancements – Fluorescence, ICP-MS (& ETAAS) suitable for ultra-trace Be determination

– Direct-reading capability shows promise but needs study

– Ability to distinguish among Be metal, alloys, and oxide desirable but needs study

• Dermal contamination on hands may be a vector for inhalation, and needs • Dermal contamination on hands may be a vector for inhalation, and needs further study– Dermal sampling of hands could be of value (new ASTM standard)

• Germany and U.S. are considering lower beryllium exposure limits– Proposed changes in U.S. regulations are expected later this year

– Impacts of these changes to be determined, and could be significant

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Contact Information

• Mike Brisson, SRNL, email mike.brisson@srs.gov, phone +1-803-952-4400

• Kevin Ashley, CDC/NIOSH, email kashley@cdc.gov, phone +1-513-841-4402

• Gary Whitney, LANL, email whitney_gary@lanl.gov, phone +1-505-665-8459

• Beryllium Health and Safety Committee web site: https://bhsc.llnl.gov

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