NIOSH Methods for Field Portable Analysis of Airborne Metals: From Development to Technology Transfer Moderator/Arranger Nicholas J. Lawryk, MPH, Ph.D.

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NIOSH Methods for Field Portable Analysis of Airborne Metals: From Development

to Technology Transfer

NIOSH Methods for Field Portable Analysis of Airborne Metals: From Development

to Technology Transfer

Moderator/ArrangerNicholas J. Lawryk, MPH, Ph.D.

Director – Airborne Metals Monitoring ProgramCDC / NIOSH, Morgantown, WV

Moderator/ArrangerNicholas J. Lawryk, MPH, Ph.D.

Director – Airborne Metals Monitoring ProgramCDC / NIOSH, Morgantown, WV

Metalworking - Basic Facts

Millions of full-time workers in construction, mining, and welding in U.S.

Exposures and health impact depend on Nature of work Time spent at the task

Methods for Analyzing Airborne Metals

Collect samples on filters

Portable technologies Can be brought on-location Same day analysis speed

Wet chemistry Non-portable Lengthy wait for results

Program Goal

Field portable technologies and methods can be developed to

provide simple, inexpensive, and fast concentration measurements of

multiple airborne metals in mining, construction, and other industries; and awareness and use of them by

potential end users can be increased.

Specific Aims

Evaluate existing NIOSH methodsEmerging technologies

Identify “best candidates” Characterize and evaluate Method development and testing

Communication interventions to raise method awareness/use

Presentation Order1. Nicholas Lawryk

Portable Instruments for Analysis of Airborne Metals: Future NIOSH Analytical Methods?

2. Kevin Ashley Screening Methods for Airborne Metals in Construction

3. Pamela Drake Measuring Airborne Metals at Mining Sites Using Portable Instruments: Advantages and Potential Problems

4. Steve Booth-ButterfieldA Message-Based Campaign for Adoption of New NIOSH Methods for Field-Portable Instruments

5. OPEN MICROPHONE - AUDIENCE

Portable Instruments for Analysis of Airborne Metals: Future NIOSH

Analytical Methods?

Portable Instruments for Analysis of Airborne Metals: Future NIOSH

Analytical Methods?

Nicholas J. Lawryk, MPH, Ph.D.Director – Airborne Metals Monitoring Program

CDC / NIOSH, Morgantown, WV

Nicholas J. Lawryk, MPH, Ph.D.Director – Airborne Metals Monitoring Program

CDC / NIOSH, Morgantown, WV

Concept

Some existing and developing field-portable technologies for measuring

multiple airborne metals show potential to be developed as NIOSH

standard methods.

Specific Aims

“If the technology is ripe…” Laboratory evaluation

Characterization studies Field sample analyses

Durability, reliability, and ease of use

Methods Using Portable Instruments in NMAM

Method 7700 - Lead by Chemical Spot Test

Method 7701 - Lead by Portable Ultrasound / ASV

Method 7702 – Lead by Portable XRFMethod 7703* – Hexavalent

Chromium by Portable Visible Spectrophotometry

* In next revision of NMAM

What Are We Looking for In A Technology?

LOD ≤ 0.1 OEL Durability Portability

No larger than a carry-on suitcase Weight under 25 pounds

Relatively inexpensive (< $25k) Easy to use and maintain Economical to operate Safe to use and transport Short analysis time

Elements of InterestNickelChromium ManganeseZincCadmiumCopperLeadIron

Some Health Effects from Airborne Metal Exposures

Ni Mn

Cd PbCr Zn Cu Fe

Metal fume fever

Liver damage

Cancer

Asthma

Sinus problems

Parkinson’s DiseaseCNS disordersPneumoconiosis

Kidney damage

Technologies in Contention

Laser Induced Breakdown Spectroscopy (LIBS)

Spark Induced Breakdown Spectroscopy (SIBS)

X-ray fluorescence with battery powered X-ray source

Microwave Induced Plasma Spectrometry (MIP)

Pulsed Laser

Sample

Plasma Emission

Plasma Plume

LIBS Basic Theory

Gas Flow

Optical Fibers

Plasma

Spark Power Supply

Spectrometer

Spark Induced Breakdown Spectrometry (SIBS) Theory

Gas Inlet

Detector

Beam Focusing Lens

Plasma

Collimating Lens

MIP Basic Theory

Microwave Power Generator (magnetron)

Spectrometer

0

20

40

60

80

100

120

140

160

180

Cu

Ba

AgCd

Mg

MnZn

Mg

CrCr

Cu/Ag

200 220 240 260 280 300 320 340 360 380 400 420 440 460 480

Wavelength (nm)

Sig

nal in

ten

sity

(co

un

t)

Hg

MIP Spectrum of a Multi-Element Air Sample

Sample

Primary Radiation Filter

X-ray Source

Solid State X-ray Detector

Spectrometer Electronics

Computer

XRF Basic Theory

Laser Induced Breakdown Spectrometry (LIBS)

Portable version built on demand

Generally “transportable”

Can be battery powered

Broad range of elements including “low Z”

Offers real time measurement

Tricky for filter analysis

Spark Induced Breakdown Spectroscopy (SIBS)

Similar to LIBS in most benefits and

disadvantages

Battery power possible

Less expensive to build than LIBS

Thoroughly evaluated for lead and

chromium

Microwave Induced Plasma (MIP)

Prototype technology

Transportable

Real time measurement of metals in air

Characterized for 10 elements (more arepossible)

Not intended for filter analysis

X-Ray Fluorescence with Battery Powered Excitation Source

Technology ready for mass production

True field portability

Battery powered

No radioactive sealed sources

Filter analysis

Can analyze >20 elements

30 cm

Two XRF Spectrometers With Sealed Sources

TN Spectrace 9000

Controller

Probe

NITON 701 (Probe and controller in one unit)

Probe Window

7.2

SIBS* MIP‡XRF†LIBS+

Technology Comparisons: Detection Limits (µg/m3)

Chromium

5.4

10Cadmium

Lead 2.2

~140

0.18

+ Neuhauser et al., 1999

† Estimate based on and 8-hour sample on 25 mm filter

0.12

1.20

10

0.37

0.21

0.47

‡ Duan et al., 2000

* Estimated (Hunter et al., 2000)

Technology Characteristics

Battery Powered

Filter Analysis

Field Ruggedness

True Portability

Off-The-Shelf

Price (estimated US$)

LIBS SIBS MIP

Breathing Zone Samples

XRFDirect Read of Air

$ 55k $ 25k$10k $ 50k

++++

+++

+++(+)+(+) (+)

Future Research Directions Compare laboratory-based portable XRF

measurements against ICP (NMAM 7300) Experimentally generated samples Samples collected in the workplace

Analyze workplace samples on-location

Design suggestions to manufacturer and technology transfer

NMAM for successfully measured elements

Conclusion

Among currently available technologies, XRF spectrometry with a

battery powered X-ray tube has the strongest potential to be a viable field

portable screening technology for measuring multiple airborne metals.

CreditsTHERMO Noran Corp. (TN Spectrace)Thomas Eagar and Neil Jenkins (MIT)NITON Corp.Amy Hunter (PSI Corp.)Mark Fraser (Mission Research Corp.)Yixiang Duan (LANL)David Cremers (LANL)Don Sackett (Innov-X Systems)Bean (Teh-hsun) Chen (NIOSH)Sidney Soderholm (NIOSH)

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