NIOSH Manual of Analytical Methods (NMAM), Fifth Edition

NIOSH Manual of Analytical Methods (NMAM) 5th Edition 

BACKUP DATA REPORT 

NIOSH Method No. 7304

Title: Elements by ICP on PVC filters using microwave 

digestion

Analyte: 31 elements

Author/developer: Lee C. Stone, John M. Reynolds,

James Perkins and David M. Rogers

Date: 11/20/03

Disclaimer: Mention of any company or product does not constitute endorsement by the National 

Institute for Occupational Safety and Health, Centers for Disease Control and Prevention. In addition, 

citations to websites external to NIOSH do not constitute NIOSH endorsement of the sponsoring 

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these websites. All web addresses referenced in this document were accessible as of the publication 

date. 
CONTRACT CDC-200-2001-

08000

Submitted To:

National Institute for 

Occupational

Safety and Health

Robert A. Taft Laboratories

4676 Columbia Parkway

Cincinnati, Ohio 45226

Submitted By:

DataChem Laboratories, Inc.

960 West LeVoy Drive

Salt Lake City, Utah 84123-2547

ELEMENTS BY ICP ON PVC FILTERS 

J

USING MICROWAVE DIGESTION

NMAM 7304, ISSUE 1 

BACKUP DATA REPORT

,

LEE C. STONE

JOHN M. REYNOLDS

JAMES B. PERKINS

DAVID M. ROGERS
TABLE OF CONTENTS

TRACE ELEMENTS on PVC filters

INTRODUCTION..............................................................................1 

REAGENTS AND STANDARDS............................................................1 

SAMPLE PREPARATION AND INSTRUMENT CONDITIONS.....................2

Air Sampling.............................................................................2 

Sample Preparation.....................................................................4 

Instrument Conditions and Calibration..............................................5 

LIMITS OF DETECTION.....................................................................6 

PRECISION AND ACCURACY STUDY............................................................8 

Procedure for Processing the Data.....................................................9 

Analysis of Recovery....................................................................11 

Analysis of Precision...................................................................13 

Analysis of Bias..........................................................................15 

Pooled Precision, Bias, and Accuracy........................................................15 

Media Background.....................................................................18 

SUMMARY.....................................................................................19 

REFERENCES..................................................................................19 
INTRODUCTION

This method incorporates the speed of Inductively Coupled Plasma Atomic 

Emission Spectroscopy (ICP-AES) multi-element analysis along with the simplicity of 

microwave single acid digestion. Prior to the development of the procedure reported 

herein, digestions of filter media for elements involved the use of perchloric acid on 

hotplates. This new procedure eliminates the danger that is associated with the use of 

perchloric acid. It also cuts the digestion time from days to a matter of hours using 

microwave digestion. 

This method also demonstrates that PVC filters can be used for most of the 

elements studied, thereby allowing both gravimetric measurements and ICP multielement analyses to be performed on the same sample. The polyvinyl chloride (PVC) 

filters used in this method can be digested in nitric acid if a high-pressure microwave is 

employed. Single acid microwave digestion greatly simplifies the sample preparation. 

These filters have little affinity for water absorption and are therefore suitable for 

gravimetric analysis.

Of the elements studied, antimony, silver, and tin had low and extremely variable 

recoveries from PVC filters. This is possibly due to the interference of chlorine from the 

digested PVC filters. The analysis of these elements is more successful if they are 

collected on MCE filters (See Method NMAM 730x).

REAGENTS AND STANDARDS

Presented in Tables 1 and 2 are the lists of reagents and standards used for this 

method evaluation. All of the standards were made up in 20% nitric acid by the vendors. 

Table 1. List of Chemicals 

Chemical Vendor CAS# Purity Lot#

Nitric Acid J. T. Baker 7697-37-2 70% 9598-34

Water Data Chem 

Laboratories

7732-18-5 ASTM Type ll

[1]

--
Table 2. List of Standards 

Analyte Primary ID# Primary Conc. Vendor Lot#

Al IP-PS-02-012 1000 ug/mL CPI 2AF233

As IP-PS-02-012 500 ug/mL CPI 2AF233

Ba IP-PS-02-012 200 ug/mL CPI 2AF233

Be IP-PS-02-012 200 ug/mL CPI 2AF233

Ca IP-PS-02-012 1000 ug/mL CPI 2AF233

Co IP-PS-02-012 200 ug/mL CPI 2AF233

Cr IP-PS-02-012 200 ug/mL CPI 2AF233

Cu IP-PS-02-012 200 ug/mL CPI 2AF233

Fe IP-PS-02-012 500 ug/mL CPI 2AF233

Li IP-PS-02-012 200 ug/mL CPI 2AF233

Mg IP-PS-02-012 500 ug/mL CPI 2AF233

Mn IP-PS-02-012 200 ug/mL CPI 2AF233

Mo IP-PS-02-012 200 ug/mL CPI 2AF233

Na IP-PS-02-012 500 ug/mL CPI 2AF233

Ni IP-PS-02-012 500 ug/mL CPI 2AF233

Pb IP-PS-02-012 500 ug/mL CPI 2AF233

Se IP-PS-02-012 1000 ug/mL CPI 2AF233

Sr IP-PS-02-012 200 ug/mL CPI 2AF233

Ti IP-PS-02-012 200 ug/mL CPI 2AF233

V IP-PS-02-012 200 ug/mL CPI 2AF233

Y IP-PS-02-012 200 ug/mL CPI 2AF233

Zn IP-PS-02-012 200 ug/mL CPI 2AF233

Zr IP-PS-02-012 200 ug/mL CPI 2AF233

B IP-PS-02-026 10000 ug/mL EM Science B1065147

K IP-PS-02-068 10000 ug/mL EM Science B2025030

P IP-PS-02-035 10000 ug/mL EM Science B2025035

Si IP-PS-02-026 10000 ug/mL EM Science B1125060

Te IP-PS-02-040 1000 ug/mL EM Science B1125041

Tl IP-PS-02-046 10000 ug/mL EM Science A8075015

Cd IP-PS-02-028 10000 ug/mL EM Science B1025044

Pt IP-PS-02-123 10000 ug/mL EM Science B0125146

SAMPLE PREPARATION AND INSTRUMENT CONDITIONS

Air Sampling

The scope of this evaluation did not include the collection of any generated 

atmospheres. It is assumed that previous method evaluations have sufficiently evaluated 

this aspect of the analysis of the elements. A summary of the pertinent exposure limits is 

given in Table 3. 

The normal sampling procedure is as follows, although it was not applicable to 

this evaluation. Calibrated personal sampling pumps equipped with PVC filters are used 

to monitor work place exposure conditions for airborne inorganic contaminants. The 

pumps are set at a flow rate of between 1 and 4 L/min. For total sample volume, see 

Table 4. Sample loading limits can be estimated from TWA values (see Table 3), 

instrument sensitivity, and sampling flow rate [2]. A filter loading of approximately 
2 mg of dust should not be exceeded. Once collected the sample cassette filter holders 

are removed from the personal sampling pumps, the ends capped, and sent in for ICPAES analysis. 

Table 3. EXPOSURE LIMITS, CAS #, RTECS [5][6] 

 Exposure Limits, mg/m3 (Ca=carcinogen; C=ceiling limit; *not adopted due to adverse effects at this level

Element (Symbol) CAS # RTECS OSHA NIOSH ACGIH

Aluminum (Al) 7429-90-5 BD0330000 15 (total dust)

5 (respirable)

10 (total dust)

5 (respirable, fume)

2 (salt, alkyls)

10 (dust)

5 (powder, fume)

2 (salt, alkyls)

Arsenic (As) 7440-38-2 CG0525000 0.010 (inorganic) C 0.002, Ca 0.01, Ca

Barium (Ba) 7440-39-3 CQ8370000 0.5 [5]

Boron (B) (1) 7440-42-8

Beryllium (Be) 7440-41-7 DS1750000 0.002, C 0.005 Not to exceed 0.0005, Ca 0.002, Ca

Calcium (Ca) (1) 7440-70-2 Varies Varies varies

Cadmium (Cd) 7440-43-9 EU9800000 0.2, C 0.6 (dust)

0.1, C 0.3 (fume)

lowest feasible conc., Ca 0.01 (total), Ca

0.002 (respirable), Ca

Cobalt (Co) 7440-48-4 GF8750000 0.1 0.05 (dust, fume) 0.05 (dust, fume)

Chromium (II) (Cr) 22541-79-3 GB6260000 0.5 0.5 Not given

Chromium (III) (Cr) 16065-83-1 GB6261000 0.5 0.5 0.5

Chromium (VI) (Cr) 18540-29-9 GB6262000 C 0.1 0.001 (dust) 0.05 (soluble)

0.05 (insoluble), Ca

Copper (Cu) 7440-50-8 GL5325000 1 (dust, mists)

0.1 (fume)

1 (dust, mists)

0.1 (fume)

1 (dust, mists)

0.2 (fume)

Iron (Fe) 1309-37-1 NO7400000 10 (fume) as oxide 5 (dust, fume) as oxide 5 (fume) as oxide

Potassium (K) (1) 7440-09-7

Lithium (Li) (1) 7439-93-2

Magnesium (Mg) 1309-48-4 OM3850000 15 (dust) as oxide 10 (fume) as oxide* 10 (fume) as oxide

Manganese (Mn) 7439-96-5 OO9275000 C 5 1; STEL 3 0.2

Molybdenum (Mo) 7439-98-7 QA4680000 5 (soluble)

15 (total insoluble)

5 (soluble)*

10 (insoluble)*

5 (soluble)

10 (insoluble)

Sodium (Na) (1) 7440-23-5

Nickel (Ni) 7440-02-0 QR5950000 1 0.015, Ca 1.5 (metal)

(soluble)

0.2 (insoluble), Ca

Phosphorus (P) 7723-14-0 TH3500000 0.1 0.1

Lead (Pb) 7439-92-1 OF7525000 0.05 <0.1 0.05

Platinum (Pt) 7440-06-4 TP2160000 0.002 1 (metal) 1 (metal)

Selenium (Se) 7782-49-2 VS7700000 0.2 0.2 0.2

Strontium (Sr) (1) 7440-24-6 WK7849000

Tellurium (Te) 13494-80-9 WY2625000 0.1 0.1 0.1

Titanium (Ti)

 TiO2

7440-32-6

13463-67-7

XR1700000

XR2275000

As TiO2, 15

as TiO2, 5 (respirable)

lowest feasible, Ca 10

Thallium (Tl) 7440-28-0 XG3425000 0.1 (skin) (soluble) 0.1 (skin) (soluble) 0.1 (skin)

Vanadium (V)

 V2O5

7440-62-2

1314-62-1

YW240000

YW1355000

C 0.5 (respirable) as V2O5

C 0.1 (fume) as V2O5

C 0.05 0.05 (respir.) as V2O5

Yttrium (Y) 7440-65-5 ZG2980000 1 1 1

Zinc (Zn) 1314-13-2 ZH4810000 5 (ZnO fume)

15 (ZnO dust)

5 (ZnO respirable)

5; STEL 10 (ZnO fume)

5; C 15 (ZnO dust)

5; STEL 10 (ZnO fume)

10 (ZnO dust)

Zirconium (Zr) 7440-67-7 ZH7070000 5 5, STEL 10 5, STEL 10

(1) No PEL, REL, STEL data found [5][6].
Table 4. PROPERTIES AND SAMPLING VOLUMES

Properties [3] Air Volume, L @ OSHA PEL [4]

Element (Symbol) Atomic Weight MP, °C MIN MAX

Aluminum (Al) 26.98 660 5 100

Arsenic (As) 74.92 817 5 2000

Barium (Ba) 137.3 727 5(2) 200(2)

Boron (B) (1) 10.81 2300 5 2000

Beryllium (Be) 9.01 1278 1250 2000

Calcium (Ca) (1) 40.08 842 5 200

Cadmium (Cd) 112.40 321 13 2000

Cobalt (Co) 58.93 1495 25 2000

Chromium (Cr) 52.00 1890 5 1000

Copper (Cu) 63.54 1083 5 1000

Iron (Fe) 55.85 1535 5 100

Potassium (K) (1) 39.10 63 5 2000

Lithium (Li) (1) 6.94 179 100 2000

Magnesium (Mg) 24.31 651 5 67

Manganese (Mn) 54.94 1244 5 200

Molybdenum (Mo) 95.94 651 5 67

Sodium (Na) (1) 22.99 98 13 2000

Nickel (Ni) 58.71 1453 5 1000

Phosphorus (P) 30.97 44 25 2000

Lead (Pb) 207.19 328 50 2000

Platinum (Pt) 195.09 1769 1250 2000

Selenium (Se) 78.96 217 13 2000

Strontium (Sr) (1) 87.62 769 5 2000

Tellurium (Te) 127.60 450 25 2000

Titanium (Ti) 47.90 1675 5 100

Thallium (Tl) 204.37 304 25 2000

Vanadium (V) 50.94 1890 5 2000

Yttrium (Y) 88.91 1495 5 1000

Zinc (Zn) 65.37 419 5 200

Zirconium (Zr) 91.22 1852 5 200

(1) No PEL, REL, STEL data found [5][6].

(2) Air Volumes Estimated from TWA and LOQs (see Tables 3 and 7) [2].

Sample Preparation 

For all the studies in this method evaluation, blank PVC filters were spiked with 

the elements of interest and transferred to clean PTFE XP-1500 digestion vessels. To 

each vessel was added 10 mL of nitric acid and 2 mL of ASTM Type II water. Where 

applicable the blanks and QC filters were also prepared in this same manner. The 

digestion vessels were then placed into a MARS 5 programmable microwave and 

digested using the following conditions: 
MICROWAVE CONDITIONS:

METHOD Ramp to Temperature (215 °C)

POWER 1,200W 100% 

PRESSURE MAX 625 psi 

RAMP TIME 20 min.

HOLD TIME 10 min. 

COOL DOWN Auto

NUMBER OF VESSELS: 6 to12

NOTE: For this digestion procedure to be successful on PVC filters it is important that a 

programmable high-pressure microwave digestion apparatus be used. 

After digestion was complete the vessels were allowed to cool. The lids were 

then removed and the contents of the vessels were rinsed into 50 mL volumetric flasks 

with ASTM type II water and diluted to the mark. The samples were then submitted for 

ICP-AES analysis. 

ICP Instrument Conditions and Calibration \ 

The ICP spectrometer was setup and calibrated according to the manufacturers 

recommendations. An acid blank and a multi-element working standard were used for 

calibration. The two point curves obtained covered the linear working range of the 

analytes of interest. Listed in Table 5 are the concentrations of the standards that make 

up the top end of the curves produced for this method development and evaluation. 

The following multi-element combinations are chemically compatible in 20% 

HNO3.

1. Al, As, Ba, Be, Ca, Co, Cr, Cu, Fe, Li, Mg, Mn, Mo, Na, Ni, Pb, Se, Sr, Ti, V, Y, Zn, and Zr;

2. B, K, P, Si, Te, and Tl;

3. Cd;

4. Pt.

Mixture number 1 above was obtained from CPI and was used as-is. The others 

were obtained as individual solutions from EM Science. 

A Continuing Calibration Verification Standard (CCV) or standards that contain 

the analytes of interest are analyzed after every ten analyses (minimum frequency), and 

recoveries are checked with media blanks and spikes every twenty samples. 

The concentration of the standards that gives a linear calibration on the 

instruments involved in this evaluation are given in Table 5 below. 
Table 5. Calibration Standard Concentrations 

Analyte Primary ID# Primary Conc. Volume of 

Primary

Final Volume Final 

Concentration

Al IP-PS-02-012 1000 ug/mL 20 mL 2000 mL 10 ug/mL

As IP-PS-02-012 500 ug/mL 20 mL 2000 mL 5 ug/mL

Ba IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Be IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Ca IP-PS-02-012 1000 ug/mL 20 mL 2000 mL 10 ug/mL

Co IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Cr IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Cu IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Fe IP-PS-02-012 500 ug/mL 20 mL 2000 mL 5 ug/mL

Li IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Mg IP-PS-02-012 500 ug/mL 20 mL 2000 mL 5 ug/mL

Mn IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Mo IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Na IP-PS-02-012 500 ug/mL 20 mL 2000 mL 5 ug/mL

Ni IP-PS-02-012 500 ug/mL 20 mL 2000 mL 5 ug/mL

Pb IP-PS-02-012 500 ug/mL 20 mL 2000 mL 5 ug/mL

Se IP-PS-02-012 1000 ug/mL 20 mL 2000 mL 10 ug/mL

Sr IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Ti IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

V IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Y IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Zn IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

Zr IP-PS-02-012 200 ug/mL 20 mL 2000 mL 2 ug/mL

B IP-PS-02-026 10000 ug/mL 1 mL 1000 mL 10 ug/mL

K IP-PS-02-068 10000 ug/mL 5 mL 1000 mL 50 ug/mL

P IP-PS-02-035 10000 ug/mL 2 mL 1000 mL 20 ug/mL

Te IP-PS-02-040 1000 ug/mL 10 mL 1000 mL 10 ug/mL

Tl IP-PS-02-046 10000 ug/mL 2 mL 1000 mL 20 ug/mL

Cd IP-PS-02-028 10000 ug/mL 0.2 mL 1000 mL 2 ug/mL

Pt IP-PS-02-123 10000 ug/mL 2 mL 2000 mL 10 ug/mL

LIMITS OF DETECTION

The limit of detection (LOD) was determined according to the protocol given in 

the Environmental Protection Agency’s 40 CFR[7] for the determination of the minimum 

detectable limit (MDL). In this procedure, seven or more replicates are analyzed. The 

MDL for each element is then calculated. The calculated MDL must be equal to or less

than the TC by no more than a factor of 0.1. In other words, the MDL is acceptable if the 

MDL and the TC have the following relationship: 1#TC/MDL#10. Otherwise, a new 

TC must be selected and the MDL estimated again. The MDLs determined in this

manner are given in Table 6 for both instruments involved in this evaluation. For the 

balance of this evaluation, the term LOD (limit of detection) is used in place of MDL. 

The term LOQ (limit of quantitation) is then calculated as 10/3 times the LOD.

The LOD is also a function of the wavelength. The wavelength at which an 

analyte is measured is generally the most sensitive available. Where there are spectral 
interferences from other elements in a sample, it may be necessary to use an alternate 

wavelength. With a fixed wavelength instrument this is not always possible. In this 

method evaluation two different ICP instruments were used. Most of the data for this 

method evaluation was generated using a fixed channel Fisons ARL Accuris ICP-AES. 

For those analytes where there were possible interference or other problems on the 

Fisons, a Perkin Elmer Optima 3000 DV ICP-AES was employed.

The replicates along with filter blanks and quality control (QC) samples for this 

LOD study were prepared and processed through the sample digestion procedure as given 

in the section on Sample Preparation. 

Table 6. WAVELENGTHS AND DETECTON LIMITS

Wavelength (nm)[8] LOD (ug/sample) LOQ (ug/sample)

Element(a) Fisons(b) P-E(c) Fisons(b) P-E(c) Fisons(b) P-E(c)

Ag 328.07 328.068* 0.1 0.2* 0.5 0.5*

Al 308.22 308.214 2 0.5 6 2 

As 193.76 193.695* 2 0.9* 6 3*

Ba 493.41 233.529* 0.2 * 0.6 * 

B 249.68 249.772* 0.4 * 1 *

Be 313.04 313.103* 0.008 0.007* 0.03 0.02*

Ca 315.89 315.886 2 2 7 8 

Cd 228.80 226.501* 0.2 0.1* 0.7 0.4*

Co 228.62 228.615* 0.7 0.4* 2 1* 

Cr 267.72 267.712 0.7 0.3 2 0.9

Cu 324.75 324.753 0.08 0.08 0.3 0.3

Fe 259.94 259.939 14.7 5 49 16 

K 766.49 766.496 3 9

Li 670.78 610.364* 0.06 0.07* 0.2 0.2* 

Mg 279.08 279.078 0.9 0.4 3 1

Mn 257.61 257.609* 0.09 0.05* 0.3 0.2*

Mo 202.03 202.029 0.4 0.3 1 0.9

Na 589.00 589.596* 5 7* 17 22*

Ni 231.60 231.603 0.3 0.2 1 0.6

P 214.92 214.916 2 2 6 7

Pb 220.35 220.350* 1 0.7* 3 2*

Pt 203.659 265.944* 9 6* 30 21*

Sb 206.84 206.837* 0.7 * 2 *

Se 196.09 196.025 5 2 16 6 

Sr 421.55 421.545* 0.04 * 0.1 *

Te 214.27 214.287 4 2 12 5

Ti 337.28 334.942 0.2 0.1 0.6 0.4

Tl 190.86 190.794 2 1 6 4

V 292.40 292.403 0.1 0.09 0.4 0.3

Y 371.03 371.030* 0.07 0.02* 0.2 0.06*

Zn 213.85 213.855 0.2 0.4 0.8 1

Zr 339.20 343.823* 0.2 0.03* 0.6 0.1* 

* These elements were not analyzed using the Perkin-Elmer in any of the subsequent studies.

(a) Performance may vary with instrument and should be independently verified.

(b) Fisons ICP-AES .

(c) Perkin-Elmer (PE) Optima 3000 DV ICP-AES
The two instruments were comparable in LODs within at least one order of 

magnitude and more commonly within a factor of 2. 

PRECISION and ACCURACY STUDY

To determine the precision and accuracy for this method, six concentrations for 

each element ranging from 1 x LOQ to 300 x LOQ were prepared on the PVC filters. 

Table 7 gives the concentration of the analytes in ug/filter used for the study based on an 

approximation of the previously determined LOQs (ug/filter is equivalent to ug/sample). 

Table 7. CONCENTRATION OF ANALYTES in ug/sample

Element LOQ(a)1xLOQ 3xLOQ 10xLOQ 30xLOQ 100xLOQ 300xLOQ Fisons P-E

Aluminum 6 2 5.025 15 50.25 150 500.25 1500

Antimony 2 5.025 15 50.25 150 500.25 1500

Arsenic 6 3 5.025 15 50.25 150 500.25 1500

Barium 0.6 0.50384 1.504 5.0384 15.04 50.1584 150.4

Berylium 0.03 0.02 0.05092 0.152 0.5092 1.52 5.0692 15.2

Boron 1 2.51384 7.504 25.1384 75.04 250.2584 750.4

Cadmium 0.7 0.4 1.005 3 10.05 30 100.05 300

Calcium 7 8 15.075 45 150.75 450 1500.75 4500

Chromium 2 0.9 2.51384 7.504 25.1384 75.04 250.2584 750.4

Cobalt 2 1 2.51384 7.504 25.1384 75.04 250.2584 750.4

Copper 0.3 0.3 0.50384 1.504 5.0384 15.04 50.1584 150.4

Iron 49 16 10.05 30 100.5 300 1000.5 3000

Lead 3 2 5.025 15 50.25 150 500.25 1500

Lithium 0.2 0.2 0.50384 1.504 5.0384 15.04 50.1584 150.4

Magnesium 3 1 5.025 15 50.25 150 500.25 1500

Manganese 0.3 0.2 0.50384 1.504 5.0384 15.04 50.1584 150.4

Molybdenum 1 0.9 1.50884 4.504 15.0884 45.04 150.2084 450.4

Nickel 1 0.6 1.50884 4.504 15.0884 45.04 150.2084 450.4

Phosphorus 6 47 10.05 30 100.5 300 1000.5 3000

Platinum 30 21 50 150 500 1500 5000 15000

Potassium 9 10.05 30 100.5 300 1000.5 3000

Selenium 16 6 25.125 75 251.25 750 2501.25 7500

Silver 0.5 0.5 1.005 3 10.05 30 100.05 300

Sodium 17 22 25.125 75 251.25 750 2501.25 7500

Strontium 0.1 2.51384 7.504 25.1384 75.04 250.2584 750.4

Tellurium 12 5 10.05 30 100.5 300 1000.5 3000

Thallium 6 4 5.025 15 50.25 150 500.25 1500

Tin 1 25.125 75 251.25 750 2501.25 7500

Titanium 0.6 0.4 1.005 3 10.05 30 100.05 300

Vanadium 0.4 0.3 0.50384 1.504 5.0384 15.04 50.1584 150.4

Yttrium 0.2 0.6 0.25192 0.752 2.5192 7.52 25.0792 75.2

Zinc 0.8 0.4 1.005 3 10.05 30 100.05 300

Zirconium 0.6 0.03 0.5025 1.5 5.025 15 50.025 150
(a) LOQs are those given in Table 6.

At each level, six blank filters were spiked with certified standards and digested 

following the procedure outlined in the section on sample preparation. After digestion 

the samples were analyzed on the Fisons instrument, the raw data collected, and precision 

and accuracy calculated. Whenever it looked like the Fisons’ data might not pass the 

criteria the solutions were reanalyzed on the Perkin-Elmer instrument.

PROCEDURE FOR PROCESSING THE DATA:

The resulting data was entered into spreadsheets that calculated percent recovery

and precision at each level (See Tables 8 and 9). Each set of six replicates was tested for

Grubbs outliers at the 1% risk of false rejection level. No more than one Grubbs outlier 

was removed from any set of six replicates. No more than 2 Grubbs outliers were 

removed from any set of 18. However, up to 3 Grubbs outliers were removed from sets 

of 24 or more. 

Where the Precision and Accuracy criteria were met for all 6 levels, no other

processing was necessary. Where the criteria could not be met with 6 levels, the CV for

the lowest level was omitted to see if the criteria could be met. Where this was not

sufficient, the CVs at each level for each analyte were entered into a second spreadsheet

that performed a Bartlett’s test for all possible combinations of CVs for 5 and 4 

concentration levels, and in some cases for all possible combinations of CVs for 3 

concentration levels after the lowest level was omitted. Of those combinations that 

passed the Bartlett’s test, using a Chi squared for a 97.5% distribution for each respective 

number of levels considered, the combination that gave the largest Chi squared was

accepted for calculation of the pooled precision, which is the overall precision of the 

method, Srt. 

The weighted average of the bias was calculated on those levels that passed the 

Bartlett’s test for homogeneity of precision, although the bias itself was not tested for

homogeneity. (See Table 10 for the average bias at each individual concentration level.) 

From the pooled precision and the weighted average of the bias for each element, the 

accuracy of the method for each element was estimated from the Nomogram given in the 

Guidelines manual. This was accomplished by making an enlargement of the nomogram 

on the copier for easier estimation. The resulting final data is given in Table 11. 
Table 8. PERCENT RECOVERY at each CONCENTRATION LEVEL

Element(a) Instrument 1xLOQ 3xLOQ 10xLOQ 30xLOQ 100xLOQ 300xLOQ

Aluminum Fisons

Perkin-Elmer

-48.16

129.79

53.19

115.05

89.78

105.67

98.28

107.04

102.41

106.66

100.71

105.17

Antimony Fisons 108.29 25.29 14.72 55.94 75.79 111.95

Arsenic Fisons 61.79 93.29 101.45 107.27 114.24 115.84

Barium Fisons 106.90 107.16 104.11 103.53 105.83 102.22

Beryllium Fisons 110.79 102.38 104.61 103.66 109.80 107.71

Boron Fisons 57.13 86.38 95.98 99.33 103.33 101.19

Cadmium Fisons 120.89 109.65 108.47 107.18 113.46 111.68

Calcium Fisons

Perkin-Elmer

-24.83

109.63

62.06

104.82

92.68

103.49

105.04

103.77

115.26

100.99

116.25

98.13

Chromium Fisons

Perkin-Elmer

117.88

112.45

112.65

102.60

111.36

98.55

109.74

97.31

117.11

95.51

118.65

92.98

Cobalt Fisons 70.01 89.87 103.04 105.86 115.08 114.15

Copper Fisons

Perkin-Elmer

111.94

123.45

106.84

117.16

104.73

110.48

102.72

106.95

105.04

105.18

100.42

103.13

Iron Fisons

Perkin-Elmer

175.94

157.16

120.58

112.55

109.04

104.26

106.30

104.41

109.74

97.95

112.41

97.20

Lead Fisons 91.37 95.85 96.72 93.31 100.12 100.54

Lithium Fisons 101.32 97.51 95.12 93.53 89.85 81.96

Magnesium Fisons

Perkin-Elmer

109.80

113.71

105.25

107.33

102.92

104.21

100.75

106.03

102.92

104.65

97.47

101.75

Manganese Fisons 117.56 110.24 110.05 110.52 116.95 115.56

Molybdenum Fisons

Perkin-Elmer

90.94

109.69

87.79

89.75

84.03

79.67

102.92

90.83

113.53

95.71

120.57

100.44

Nickel Fisons PerkinElmer

106.41

114.06

102.93

109.91

106.96

107.23

108.02

103.48

112.74

102.86

110.59

101.77

Phosphorus Fisons

Perkin-Elmer

83.33

89.63

81.82

86.36

99.56

99.87

100.11

100.18

106.36

102.25

107.20

103.33

Platinum Fisons 99.90 104.67 103.69 100.97 106.71 105.19

Potassium Fisons

Perkin-Elmer

25.38

159.42

66.32

107.88

85.57

99.40

96.84

96.84

94.76

93.77

86.46

90.02

Selenium Fisons

Perkin-Elmer

104.59

100.69

102.05

99.93

106.75

100.88

108.05

99.78

111.50

101.15

111.35

99.72

Silver Fisons 104.71 63.01 31.29 9.50 6.19 3.92

Sodium Fisons 211.30 124.56 107.19 97.61 92.43 83.07

Strontium Fisons 96.29 100.00 101.09 101.79 103.73 99.54

Tellurium Fisons

Perkin-Elmer

102.53

101.63

95.80

97.18

76.24*

74.98**

102.33

98.36

110.37

100.62

110.81

99.64

Thallium Fisons

Perkin-Elmer

80.03

99.51

96.38

97.75

101.31

96.33

101.48

93.12

103.34

93.75

97.25

92.04

Tin Fisons

Perkin-Elmer

54.57

73.72

30.82

37.87

33.41

40.81

63.30

80.54

75.80

93.63

79.56

92.34

Titanium Fisons

Perkin-Elmer

94.16

88.92

81.66

82.68

88.42

88.22

91.04

85.91

88.52

85.88

103.42

96.13

Vanadium Fisons

Perkin-Elmer

110.02

100.26

104.54

100.99

104.38

98.64

105.60

97.82

111.95

99.37

111.15

99.38

Yttrium Fisons 105.18 105.98 106.31 104.66 107.96 105.03

Zinc Fisons

Perkin-Elmer

129.76

88.29

110.76

93.45

110.01

96.12

106.30

94.60

115.38

95.09

116.84

94.01

Zirconium Fisons 106.48 102.61 101.96 99.04 103.51 101.56
* Average recovery is 101.27% when the 3 replicates are removed having about 50% recovery.

** Average recovery is 98.06% when the 3 replicates are removed having about 50% recovery.

Bold numbers in Table 7 are recoveries greater than 120% or less than 80%.

ANALYSIS OF RECOVERY (Refer to Table 8)

With 3 exceptions, recoveries were very good, meaning that the recoveries were 

between 80 to 125% on at least 5 of the six levels for at least one of the instruments. The 

exceptions were antimony, silver, and tin. Recoveries for Antimony and silver were so 

bad that no attempt was made to reanalyze them on the Perkin-Elmer. Recoveries for tin

were poor on the Fisons, but improved at the upper 3 concentration levels on the PerkinElmer. Excluding those 3 elements, of the remaining 276 data points only 23 were either 

above 120% or below 80% recovery. If the 1xLOQ level is omitted, then only 6 of 230 

data points were below 80% and 3 just barely above 120%. This signals very good 

recoveries in general. However, recoveries were not constant across the concentration 

range. Nearly a third of the elements were generally decreasing in recovery and a third

were generally increasing in recoveries. This has an affect on the homogeneity of the 

bias, to be discussed later in this report. 

Of the 6 low recoveries, excluding antimony, silver, and tin, 2 of them were at the 

10xLOQ level for tellurium, one for the Fisons and the other for the Perkin-Elmer. This

set of replicates had 3 of 6 that were about 50% (43-57%) of what they were supposed to 

be while the other 3 were 97-107% of target. This suggests that they were either missspiked or losses occurred during sample processing. Because there were 3 apparent 

outliers, they could not be removed by the Grubbs test which allows for only one outlier 

to be removed. Nevertheless, they probably were outliers because it was obvious that 

they were out of character with both the levels immediately above and below where the 

recoveries ranged from 90 to 106%. However, in obtaining the pooled CV and the 

weighted averaged bias it was convenient to remove this level entirely. 

A similar situation existed within the 100xLOQ level for titanium where one

replicate had a low recovery which just barely could not pass the Grubbs test. The CVs 

for titanium were able to pass the Bartlett’s test when the 100xLOQ level was omitted

entirely. 
Table 9. PRECISION at each CONCENTRATION LEVEL

Element(a) Instrument 1xLOQ 3xLOQ 10xLOQ 30xLOQ 100xLOQ 300xLOQ

Aluminum Fisons

Perkin-Elmer

-0.13135

0.6222

0.07108

0.01990

0.05647

0.04329

0.04193

0.05515

0.01844

0.01494

0.00550

0.00557

Antimony Fisons 0.06795 0.58611 0.39811 0.55483 0.45773 0.00860

Arsenic Fisons 0.21277 0.05706 0.05106 0.03121 0.06093 0.01743

Barium Fisons 0.05702 0.02945 0.01755 0.01417 0.01656 0.01043

Berylium Fisons 0.10771 0.08614 0.01305 0.01979 0.02007 0.00905

Boron Fisons 0.11443 0.02770 0.01042 0.01551 0.00373 0.00817

Cadmium Fisons 0.09103 0.03163 0.04098 0.02950 0.00667 0.01523

Calcium Fisons

Perkin-Elmer

-0.15397

0.02403

0.02410

0.00897

0.05120

0.02745

0.02741

0.03656

0.01766

0.01264

0.01527

0.00657

Chromium Fisons

Perkin-Elmer

0.06810

0.01590

0.02329

0.00480

0.01986

0.01625

0.03299

0.01830

0.00997

0.00946

0.01363

0.00666

Cobalt Fisons 0.17799 0.03377 0.03639 0.02700 0.01319 0.01405

Copper Fisons

Perkin-Elmer

0.06594

0.07000

0.03639

0.03613

0.01512

0.01726

0.01352

0.01874

0.02691

0.01855

0.00585

0.01497

Iron Fisons

Perkin-Elmer

0.37295

0.43215

0.04050

0.04896

0.03240

0.03163

0.05388

0.05141

0.02737

0.02537

0.00833

0.00845

Lead Fisons 0.10415 0.03086 0.03825 0.02318 0.02716 0.01542

Lithium Fisons 0.03530 0.02527 0.01304 0.01536 0.02854 0.03781

Magnesium Fisons

Perkin-Elmer

0.04184

0.03663

0.00880

0.00430

0.02285

0.02661

0.01271

0.01516

0.02430

0.01408

0.00769

0.00586

Manganese Fisons 0.02435 0.01504 0.02429 0.02707 0.01257 0.00901

Molybdenum Fisons

Perkin-Elmer

0.10744

0.01606

0.04332

0.02152

0.04907

0.01888

0.10487

0.08228

0.06227

0.06060

0.00930

0.01543

Nickel Fisons PerkinElmer

0.14563

0.01629

0.04750

0.00471

0.03754

0.02347

0.02807

0.00907

0.01884

0.01906

0.00808

0.01389

Phosphorus Fisons

Perkin-Elmer

0.14554

0.04185

0.05116

0.00770

0.04639

0.03744

0.02499

0.00982

0.00813

0.01195

0.01029

0.01739

Platinum Fisons 0.12157 0.01817 0.03058 0.03082 0.01509 0.00879

Potassium Fisons

Perkin-Elmer

0.29584

0.24737

0.08464

0.16547

0.02537

0.03008

0.01260

0.02889

0.03674

0.01779

0.02597

0.02053

Selenium Fisons

Perkin-Elmer

0.07610

0.01446

0.05316

0.00510

0.02358

0.03620

0.01488

0.01009

0.00923

0.01951

0.00633

0.00819

Silver Fisons 0.06792 0.07391 1.16058 0.19928 0.82078 0.08656

Sodium Fisons 0.19601 0.08589 0.02622 0.01229 0.03116 0.02477

Strontium Fisons 0.00314 0.00491 0.02057 0.01488 0.01505 0.00545

Tellurium Fisons

Perkin-Elmer

0.17814

0.02015

0.06240

0.01000

0.36530*

0.34382**

0.03211

0.02299

0.01286

0.00940

0.00944

0.00743

Thallium Fisons

Perkin-Elmer

0.28641

0.03295

0.06058

0.00328

0.04364

0.03679

0.01677

0.01020

0.03432

0.02093

0.01488

0.01195

Tin Fisons

Perkin-Elmer

0.03626

0.02704

0.05026

0.08164

0.10670

0.11068

0.15248

0.16060

0.03928

0.03434

0.01240

0.01289

Titanium Fisons

Perkin-Elmer

0.19395

0.04812

0.03928

0.03737

0.02617

0.02429

0.10189

0.08879

0.26058

0.16405

0.01016

0.01213

Vanadium Fisons

Perkin-Elmer

0.11184

0.03255

0.05286

0.01468

0.01095

0.01410

0.02773

0.00894

0.00671

0.01546

0.01602

0.02320

Yttrium Fisons 0.07897 0.02445 0.01503 0.02044 0.01088 0.00727

Zinc Fisons

Perkin-Elmer

0.05967

0.12053

0.03269

0.03505

0.05931

0.02424

0.03132

0.00650

0.02247

0.02950

0.01525

0.00556

Zirconium Fisons 0.07239 0.02424 0.01245 0.02384 0.00405 0.01439

* CV is 0.04778 when the 3 replicates are removed having about 50% recovery.

** CV is 0.02073 when the 3 replicates are removed having about 50% recovery.
Bold numbers are those that exceed 0.1000 (10%RSD) or are negative in sign.

Numbers that are shaded are less than 0.0200 (2%RSD). 

ANALYSIS OF PRECISION: (Refer to Table 9.

Only a few elements analyzed were able to pass the Precision and Accuracy

criteria with all 6 levels considered on either the Fisons or the Perkin-Elmer. On the

Fisons these were Lithium, Manganese, and Zinc. On the Perkin-Elmer only Chromium, 

Selenium, and Vanadium were able to pass all criteria with all 6 levels considered.

When the 1xLOQ level was omitted from consideration several additional metals

were able to meet all the criteria. On the Fisons these were Calcium, Chromium,

Platinum, Yttrium, and Zirconium, and on the Perkin-Elmer they were Copper and 

Nickel.

The primary reason for the elements not meeting the Precision and Accuracy 

criteria was the non-homogeneity of precision. The homogeneity of precision was tested 

using the Bartlett’s test. The homogeneity of the bias was not tested, but it was apparent 

from looking at the data that the bias (percent recoveries) were, as were the precisions, a

function of concentration. At the higher levels the precisions were very small compared 

to the lower levels. This is observable in Table 9 where all CVs that were less than

0.02000 are shaded. Most of the shaded entries are at the right side in the table. These 

values might be considered “inliers”.

At the 300xLOQ level the precisions were almost without exception below 

2%RSD. If the CVs for antimony, silver, and tin are excluded, the average of all the CVs 

at the 100xLOQ level is about twice the average of those at the 300xLOQ level. At the 

30xLOQ level, the average is about 3 times that at 300x LOQ. At the 10x and 3xLOQ 

level, the average is about 4 times that at 300x LOQ, and at the 1xLOQ level, the average 

CV is about 7.4 times that at 300xLOQ. From experience it has been observed that, 

roughly speaking, when any CV is more than about twice its neighbors, it usually doesn’t 

pass the Bartlett’s test. Since on average so many CVs are 3 and 4 times greater than

those at 300 or 100xLOQ, either the 100x and 300xLOQ level data has to be excluded in 

spite of its excellent precision, or some of the data at the lower levels has to be excluded, 

even though the precisions at these levels often only range from 3-9%RSD, which is 

certainly not very bad.

By selectively removing data it is possible to get a set of CVs that satisfy

Bartlett’s test. But often this creates what might be regarded as an artificial pooled

precision. If apparent inliers are removed, then the precision appears to be worse than it

really is at the higher concentrations. But if the lower level CVs are removed, then the 

precision appears to be much better than it really is at the low levels. The situation is 

simply this: For most of the elements the precision and bias cannot be predicted for 

concentration levels not studied. But it might be safe to say that since the precision and 

recovery generally improve with increasing concentration, that the accuracy of the 

method for higher concentrations is at least as good or better than that for the highest 

level tested, the 300xLOQ level. 

The values at the 3xLOQ level will be generally indicative of conditions at the 

lower concentration levels, while those at the 300xLOQ level will be indicative of the 

expectations for levels above the 300xLOQ level. 

Because the spiked PVC filters were not weathered, nor were atmospheres

generated, the Precision and Accuracy study is essentially a Desorption Efficiency study.

The precision values obtained in this study are in effect Sr1 for analytical samples and

not Sr2 for generated samples, according to the Guidelines manual (page 60). 
Table 10. AVERAGE BIAS at each CONCENTRATION LEVEL

Element(a) Instrument 1xLOQ 3xLOQ 10xLOQ 30xLOQ 100xLOQ 300xLOQ

Aluminum Fisons

Perkin-Elmer

-1.4816

0.2979

-0.4681

0.1505

-0.1022

0.0567

-0.0172

0.0704

0.0241

0.0666

0.0071

0.0517

Antimony Fisons 0.0829 -0.7471 -0.8528 -0.4406 -0.2421 0.1195

Arsenic Fisons -0.3821 -0.0671 0.0145 0.0727 0.1148 0.1584

Barium Fisons 0.0690 0.0716 0.0411 0.0353 0.0513 0.0222

Beryllium Fisons 0.1079 0.0238 0.0461 0.0366 0.0980 0.0771

Boron Fisons -0.4287 -0.1362 -0.0402 -0.0067 0.0333 0.0119

Cadmium Fisons 0.2089 0.0965 0.0847 0.0718 0.1346 0.1168

Calcium Fisons

Perkin-Elmer

-1.2483

0.0963

-0.3794

0.0482

-0.0732

0.0349

0.0504

0.0377

0.1526

0.0099

0.1625

-0.0187

Chromium Fisons

Perkin-Elmer

0.1788

0.1245

0.1265

0.0260

0.1136

-0.0145

0.0974

-0.0269

0.1711

-0.0449

0.1865

-0.0702

Cobalt Fisons -0.2999 -0.1013 0.0304 0.0586 0.1508 0.1415

Copper Fisons

Perkin-Elmer

0.1194

0.2345

0.0684

0.1716

0.0473

0.1048

0.0272

0.0695

0.0504

0.0518

0.0042

0.0313

Iron Fisons

Perkin-Elmer

0.7594

0.5716

0.2058

0.1255

0.0904

0.0426

0.0630

0.0441

0.0974

-0.0205

0.1241

-0.0280

Lead Fisons -0.0863 -0.0415 -0.0328 -0.0669 0.0124 0.0054

Lithium Fisons 0.0132 -0.0249 -0.0488 -0.0647 -0.1015 -0.1804

Magnesium Fisons

Perkin-Elmer

0.0980

0.1371

0.0525

0.0733

0.0292

0.0421

0.0075

0.0603

0.0203

0.0465

-0.0253

0.0175

Manganese Fisons 0.1756 0.1024 0.1005 0.1052 0.1695 0.1556

Molybdenum Fisons

Perkin-Elmer

-0.0906

0.0969

-0.1221

-0.1025

-0.1597

-0.2033

0.0292

-0.0917

0.1353

-0.0429

0.2057

0.0044

Nickel Fisons PerkinElmer

0.0641

0.1406

0.0293

0.0991

0.0696

0.0723

0.0802

0.0348

0.1274

0.0286

0.1059

0.0177

Phosphorus Fisons

Perkin-Elmer

-0.1667

-0.1037

-0.1818

-0.1364

-0.0044

-0.0013

0.0011

0.0018

0.0636

0.0225

0.0720

0.0333

Platinum Fisons -0.0010 0.0467 0.0369 0.0097 0.0671 0.0519

Potassium Fisons

Perkin-Elmer

-0.7462

0.5942

-0.3368

0.0788

-0.1443

-0.0060

-0.0316

-0.0316

-0.0524

-0.0623

-0.1354

-0.0998

Selenium Fisons

Perkin-Elmer

0.0459

0.0069

0.0205

-0.0007

0.0675

-0.0088

0.0805

-0.0022

0.1150

0.0115

0.1135

-0.0028

Silver Fisons 0.0471 -0.3699 -0.6871 -0.9050 -0.9381 -0.9608

Sodium Fisons 1.1130 0.2456 0.0719 -0.0239 -0.0757 -0.1693

Strontium Fisons -0.0371 -0.0000 0.0109 0.0179 0.0373 -0.0046

Tellurium Fisons

Perkin-Elmer

0.0253

0.0163

-0.0420

-0.0282

-0.2376*

-0.2502**

0.0233

-0.0164

0.1037

0.0062

0.1081

-0.0036

Thallium Fisons

Perkin-Elmer

-0.1997

-0.0049

-0.0362

-0.0225

0.0131

-0.0367

0.0148

-0.0688

0.0334

-0.0625

-0.0275

-0.0796

Tin Fisons

Perkin-Elmer

-0.4543

-0.2628

-0.6918

-0.6213

-0.6659

-0.5919

-0.3670

-0.1946

-0.2420

-0.0637

-0.2044

-0.0766

Titanium Fisons

Perkin-Elmer

-0.0584

0.1108

-0.1834

-0.1732

-0.1158

-0.1178

-0.0896

-0.1409

-0.1148

-0.1412

0.0342

-0.0387

Vanadium Fisons

Perkin-Elmer

0.1002

0.0026

0.0454

0.0099

0.0438

-0.0136

0.0560

-0.0218

0.1195

-0.0063

0.1115

-0.0062

Yttrium Fisons 0.0518 0.0598 0.0631 0.0466 0.0796 0.0503

Zinc Fisons

Perkin-Elmer

0.2976

-0.1171

0.1076

-0.0655

0.1001

-0.0388

0.0630

-0.0540

0.1538

-0.0491

0.1684

-0.0599

Zirconium Fisons 0.0648 0.0261 0.0196 -0.0096 0.0351 0.0156

* Bias is 0.0126 if three replicates around 50% recovery are removed. ** Bias is -0.0194 if three replicates 

around 50% recovery are removed. Bold numbers are Bias values greater than plus or minus 0.2000. Shaded 

numbers are Bias values greater than plus or minus 0.1000. 
ANALYSIS OF BIAS: (Refer to Table 10.) 

The comments made in reference to the percent recoveries are applicable to the 

bias as well. Table 10 reflects the same information as is given in Table 8. Also, the fact 

that this precision and accuracy study is based upon analytical samples and not generated 

samples might affect the interpretation of the extent of bias. Because the definition of 

the method bias excludes correctable bias, which is bias that can be explained as a 

desorption efficiency, and since this precision and accuracy study is essentially a 

desorption efficiency study, therefore biases of greater than plus or minus 10% must be 

allowed. Therefore, the 10% cut-off rule was not followed. In Table 10, biases that are 

greater than an absolute value of 10% are shaded. 

The biases were not tested for homogeneity. It is apparent that there was a lot of 

dependency upon concentration in over half of the analyses independent of which 

instrument was used. 

FINAL POOLED PRECISION, BIAS, AND ACCUARCY: (Refer to Table 11.) 

Using the concentration levels that passed Bartlett’s test on either instrument, the 

following data was determined. In the far right hand column of Table 11 the 

concentration levels are listed that had to be omitted in order to make the data pass the 

Bartlett’s test. This included some very good data that were either inliers, or data that 

would not pool because the remaining data contained inlier CVs. 

In Table 12 are listed the recoveries and precision for the 3xLOQ and 300xLOQ 

levels in consolidated form. Data from both the Fisons and the Perkin-Elmer are 

included for comparison and to show that the data is fairly comparable in most cases. In 

several cases with the Fisons data the 3xLOQ data is substituted with the 10xLOQ data 

because of low recoveries at the 3xLOQ level. Where recoveries were also low at the 

10xLOQ level, the 3xLOQ level data was retained and no was substitution made. From 

this table it is apparent that even though much of the data was not poolable across all 

concentration levels, the recoveries and precision still appeared to be good. 
Page 16 of 12

Table 11. POOLED PRECISION, BIAS, and ACCURACY

Element Instrument Bias 

Range of Bias Precision

SrT

Accuracy

xLOQ Conc.

Levels

Omitted From To (a)

Aluminum Fisons

Perkin-Elmer

-0.03179

0.08325

-0.10224

0.05672

0.02406

0.15047

0.04198

0.03789

9.9

15.1

1,3,300 (b)

1,300 (b)

Antimony Fisons Poor and variable recoveries across study range.

Arsenic Fisons 0.06299 -0.06705 0.15837 0.04610 14.3 1

Barium Fisons 0.04336 0.02221 0.07163 0.01817 7.6 1

Beryllium Fisons 0.06524 0.03661 0.09799 0.01633 9.5 1,3

Boron Fisons -0.03874 -0.13619 0.01188 0.01646 6.4 1,100 (b)

Cadmium Fisons 0.09227 0.07181 0.11676 0.03070 14.8 1,100 (b)

Calcium Fisons

Perkin-Elmer

0.07796

0.04530

-0.05363

0.00988

0.16246

0.09630

0.03130

0.02454

13.4

8.8

1,3

300 (b)

Chromium Fisons

Perkin-Elmer

0.13945

-0.00175

0.09742

-0.07016

0.18650

0.12454

0.02142

0.01316

18

<5

1

none

Cobalt Fisons 0.05924 -0.10130 0.15079 0.02635 10.4 1

Copper Fisons

Perkin-Elmer

0.04745

0.08287

0.02721

0.03131

0.06841

0.17161

0.02403

0.02171

8.9

12.1

1,300 (b)

1

Iron Fisons

Fisons

Perkin-Elmer

0.11018

0.08362

0.04456

0.06302

0.06302

-0.02049

0.20578

0.09742

0.12547

0.03978

0.03959

0.04041

18.6

15.4

11.4

1,300 (b)

1,3,300 (b)

1,300 (b)

Lead Fisons -0.02409 -0.06686 0.01240 0.02791 6.9 1

Lithium Fisons -0.06908 -0.18040 0.01319 0.02757 11.1 none

Magnesium Fisons

Perkin-Elmer

0.01560

0.07151

-0.02530

0.04212

0.05246

0.13715

0.01705

0.02489

<5

11.5

1

3,300 (b)

Manganese Fisons 0.13571 0.10053 0.17556 0.02007 17.3 none

Molybdenum Fisons

Perkin-Elmer

-0.03878

-0.04891

-0.15965

-0.20331

0.13527

0.09687

0.07949

0.01794

16.7

7.7

300 (b)

30,100

Nickel Fisons

Perkin-Elmer

0.07873

0.06456

0.02934

0.01765

0.12744

0.14061

0.03386

0.01593

13.8

9.2

1,300 (b)

none

Phosphorus Fisons

Perkin-Elmer

-0.05463

-0.01630

-0.18183

-0.13640

0.00114

0.03333

0.04170

0.01248

12

<5

1,100 (b),300 (b)

1,10

Platinum Fisons 0.04232 0.00971 0.06712 0.02261 8.2 1

Potassium Fisons

Perkin-Elmer

-0.09093

-0.04992

-0.14431

-0.09983

-0.03164

-0.00597

0.02658

0.02489

13.1

8.8

1,3

1,3

Selenium Fisons

Perkin-Elmer

0.09414

0.00266

0.06753

-0.00278

0.11497

0.01149

0.01502

0.01274

12.1

<5

1,3

10

Silver Fisons Poor and variable recoveries across study range.

Sodium Fisons -0.04926 -0.16935 0.07188 0.02461 8.8 1,3

Strontium Fisons 0.01722 -0.00002 0.03731 0.01531 <5 1,300 (b)

Tellurium Fisons

Perkin-Elmer

0.02949

-0.00436

-0.04203

-0.02823

0.10369

0.01625

0.04041

0.01553

9.8

<5

1,300 (b)

10

Thallium Fisons

Perkin-Elmer

-0.00811

-0.05050

-0.03622

-0.06883

0.03339

-0.00486

0.04072

0.02500

8.2

9

1,300 (b)

3 (b)

Tin Fisons

Perkin-Elmer Poor and variable recoveries across study range.

Titanium Fisons

Perkin-Elmer

-0.08272

-0.10724

-0.18337

-0.17323

0.03424

-0.03867

0.02687

0.03209

12.3

15.3

1,30,100

30,100

Vanadium Fisons

Perkin-Elmer

0.07042

-0.00634

0.04384

-0.02178

0.11148

0.00991

0.01954

0.01986

10.5

<5

1,3,100 (b)

none

Yttrium Fisons 0.05988 0.04659 0.07958 0.01641 8.9 1

Zinc Fisons

Fisons

Perkin-Elmer

0.14522

0.11895

-0.05028

0.06299

0.06299

-0.06550

0.29755

0.16838

-0.03881

0.03995

0.03562

0.02952

22

18.7

9.6

None

1 

1,30 (b),300 (b)

Zirconium Fisons 0.01639 -0.00963 0.03508 0.01753 <5 1

(a) Concentration levels that were omitted to permit CVs to pass Bartlett’s test for homogeneity.

(b) These levels had CVs that were inliers.
Page 17 of 12

Table 12. RECOVERIES AND PRECISION AT 3xLOQ AND 300xLOQ

Element(a) Wavelength

(nm)

LOD

(ug/sample)

30xLOQ 300xLOQ

ug/sample N

=

Percent

Recovery

Precision

(Sr) ug/sample N=

Percent

Recovery

Precision

(Sr)

Ag 328.07 0.1 3.00 5 63.01 0.07391 300 6 3.92 0.08656

Al

Al(b)

308.22

308.214

2

0.5

50.25 (d)

15.0

6

5

89.78

115.05

0.05647

0.01990

1500

1500

6

6

100.71

105.17

0.00550

0.00557

As 193.76 2 15.0 5 93.29 0.05706 1500 6 115.84 0.01743

Ba 493.41 0.2 1.50 5 107.16 0.02945 150 6 102.22 0.01043

B 249.68 0.4 7.50 5 86.38 0.02770 750 6 101.19 0.00817

Be 313.04 0.008 0.152 6 102.38 0.08614 15.2 6 107.71 0.00905

Ca

Ca(b)

315.89

315.886 2

151 (d)

45.0

6

5

94.64

104.82

0.05120

0.00897

4500

4500

6

6

116.25

98.13

0.01527

0.00657

Cd 228.80 0.2 3.00 5 109.65 0.03163 300 6 111.68 0.01523

Co 228.62 0.7 7.50 5 89.87 0.03377 750 6 114.15 0.01405

Cr

Cr(b)

267.72

267.712

0.7

0.3

7.50

7.50

5

5

112.65

102.60

0.02329

0.00480

750

750

6

6

118.65

92.98

0.01363

0.00666

Cu

Cu(b)

324.75

324.753

0.08

0.08

1.50

1.50

5

5

106.84

117.16

0.03639

0.03613

150

150

6

6

100.42

103.13

0.00585

0.01497

Fe

Fe(b)

259.94

259.939

15

5

30

30

5

5

120.58

112.55

0.04050

0.04896

3000

3000

6

6

112.41

97.20

0.00833

0.00845

K

K(b)

766.49

766.496

3 100 (d)

100 (d)

6

6

85.57

99.40

0.02537

0.03008

3000

3000

6

6

86.46 

90.02

0.02597

0.02053

Li 670.78 0.06 1.50 5 97.51 0.02527 150 6 81.96 0.03781

Mg

Mg(b)

279.08

279.078

0.9

0.4

15.0

15.0

5

5

105.25

107.33

0.00880

0.00430

1500

1500

6

6

97.47

101.75

0.00769

0.00586

Mn 257.61 0.09 1.50 5 110.24 0.01504 150 6 115.56 0.00901

Mo

Mo(b)

202.03

202.029

0.4

0.3

4.50

4.50

5

5

87.79

89.75

0.04332

0.02152

450

450

6

6

120.57

100.44

0.00930

0.01543

Na 589.00 5 75.0 6 124.56 0.08589 7500 6 83.07 0.02477

Ni

Ni(b)

231.60

231.603

0.3

0.2

4.50

4.50

5

5

102.93

109.91

0.04750

0.00471

450

450

6

6

110.59

101.77

0.00808

0.01389

P

P(b)

214.92

214.916

2

2

30.0

30.0

5

5

81.82

86.36

0.05116

0.00770

3000

3000

6

6

107.20

103.33

0.01029

0.01739

Pb 220.35 1 15.0 5 95.85 0.03086 1500 6 100.54 0.01542

Pt 203.65 9 150 5 104.67 0.01817 15000 6 105.19 0.00879

Sb(c) 206.84 0.7 15.0 6 25.29 0.58611 1500 6 111.95 0.00860

Se

Se(b)

196.09

196.025

5

2

75.0

75.0

5

5

102.05

99.93

0.05316

0.00510

7500

7500

6

6

111.35

99.72

0.00633

0.00819

Sn

Sn(b,c)

189.9

189.9 0.4

75.0

75.0

5

5

30.82

37.87

0.05026

0.08164

7500

7500

6

6

79.56

92.34

0.01240

0.01289

Sr 421.55 0.04 7.50 5 100.00 0.00491 750 6 99.54 0.00545

Te

Te(b)

214.27

214.287

4

2

30.0

30.0

5

5

95.80

97.18

0.06240

0.01000

3000

3000

6

6

110.81

99.64

0.00944

0.00743

Ti

Ti(c)

337.28

334.942

0.2

0.1

3.00

3.00

5

5

81.66

82.68

0.03928

0.03737

300

300

6

6

103.42

96.13

0.01016

0.01213

Tl

Tl(c)

190.86

190.794

2

1

15.0

15.0

5

5

96.38

97.75

0.06058

0.00328

1500

1500

6

6

97.25

92.04

0.01488

0.01195

V

V(b)

292.40

292.403

0.1

0.09

1.50

1.50

5

5

104.54

100.99

0.05286

0.01468

150

150

6

6

111.15

99.38

0.01602

0.02320

Y 371.03 0.07 0.752 5 105.98 0.02445 75.2 6 105.03 0.00727

Zn

Zn(b)

213.85

213.855

0.2

0.4

3.00

3.00

5

5

110.76

93.45

0.03269

0.03505

300

300

6

6

116.84

94.01

0.01525

0.00556

Zr 339.20 0.2 1.50 5 102.61 0.02424 150 6 101.56 0.01439

(a) Values reported were obtained with a Fisons ARL Accuris ICP-AES unless otherwise noted;

performance may vary with instrument and should be independently verified.

(b) Values reported were obtained with a Perkin Elmer Optima 3000 DV ICP-AES.

(c) Elements that were evaluated and found not suitable for analysis by this method.

(d) Values given are for the 10xLOQ level due to low recoveries at the 3xLOQ level.
Page 18 of 12

Media Background 

Media blank results for PVC filters showed only the calcium, boron and aluminum 

blanks to be higher than there LOQ’s, but less than the operating range. Thus, with the 

practical operating range being from 3xLOQ to 300xLOQ, subtraction of the media blank from 

the spiked filter results was not found to be necessary. 

Table 13: MEDIA BACKGROUND RESULTS(a)

(a) Values and LOQs reported were obtained with a Fisons ARL Accuris ICP-AES and Perkin

Elmer Optima 3000 DV ICP-AES; performance may vary with instrument and should be

independently verified.

Element(a) Average 

(N=6) 

(ug/sample)

LOQ

(ug/sample)

Al 8.72 7 

As -1.44 7

Ba 0.0546 0.7

B 1.81 1

Be -0.0026 0.03

Ca 20.3 7

Cd 0.242 0.7

Co -0.674 2

Cr 0.105 2

Cu 0.0210 0.3

Fe 2.71 50

K -4.07 10

Li 0.0530 0.2

Mg 0.534 3

Mn 0.0312 0.3

Mo -0.323 1

Na 12.5 20

Ni -0.0312 1

P 0.109 7

Pb -0.383 3 

Pt 3.13 30

Se 0.677 20

Sr 0.173 0.1

Te -1.31 10

Ti 0.191 0.7

Tl -0.690 7

V -0.0291 0.3

Y -0.0126 0.2

Zn 0.283 0.7

Zr 0.0314 0.7
Page 19 of 12

SUMMARY AND COMMENTS

The method evaluated herein passes the NIOSH criteria with the special exceptions 

noted because of the inliers and the fact that the precision and accuracy determinations were 

made on analytical samples and not on generated samples. The exceptional precision generally 

at the higher concentration levels in many of the metals makes it difficult for the CVs to pass 

Bartlett’s test for homogeneity. 

Only three metals failed on PVC filters in the range studied. These were silver, 

antimony, and tin. This is believed to be due to the presence of chorine from the PVC filters 

from digestion. 

One metal, tellurium, had 3 replicates of 6 at the 10xLOQ level that were about 50% 

recovery. With the Perkin-Elmer results that entire level was omitted to permit the remaining 

CVs to pass Bartlett’s test. But with the Fisons data, no combination of CVs from three or 

more levels would pass Bartlett’s test. This is because two CVs were inliers and two others 

were mid range and the two remaining were very large. Any of these pairs would pass but not 

any combination of three or more. But if the three low recovery replicates at the 10xLOQ level 

were omitted, then four concentration levels did pass Bartlett’s test. But a statistical 

justification for removing those three replicates is unknown, except that they were definitely 

out of character with the levels at either higher or lower concentrations. This set was an 

extreme example of the problem with inliers making it difficult to find enough levels to pool 

when something happens to one set of replicates. 

If each level is taken by itself without having to pool with its neighboring concentration 

levels, the data seems adequate in both recovery and precision (recoveries 81-121% and 

relative standard deviations less than 0.1100 in the worst cases, and most of them better than 

these values).

With most of the metals the CV appeared to be a function of concentration. The 

smallest CVs were at the highest concentrations. Omitting the CV at the highest concentration 

level has the consequence of creating overall precisions that are larger than what would 

probably be encountered at concentrations above the range studied. 

When the data was initially processed, all Grubbs outliers with a 1% risk of false 

rejection or less were removed. This had the unintended consequence of creating inlier CVs 

from the remaining 5 replicates in a large number of cases. It was decided that returning these 

data points was the wise and conservative thing to do even though their removal might be 

justified simply on the setting of a 1% threshold limit. By returning these values the resulting 

CVs were often raised from less than 1% to a more reasonable 3 or 4%, making it easier for the 

Bartlett’s test to pass more levels. By lowering the Grubbs outlier threshold to 0.1%, or in 

worse case to 0.5%, much more data was able to pass the Bartlett’s test. This was probably the 

right thing to do since it is better to give conservative precision estimates than those which are 

overly small. Even so, many of the metals still have very small overall precisions.

This method is for the analysis of metal and nonmetal dust collected on PVC filters in 

the workplace and environment in general. This method increases the applicability of NMAM 

7300 [4]. Using a microwave digestion approach simplifies and expedites the analysis. The 

elimination of perchloric acid [9] in the sample digestion helps to improve the safety of the 

method. 
Page 20 of 12

REFERENCES

[1] ASTM # 1193-77 (1983).

[2] “The Industrial Environment - its Evaluation & Control”, NIOSH, U.S. Department of

Health Education and Welfare, (1973).

[3] Lide, D R “Handbook of Chemistry and Physics”, 74th Edition, ISBN: 0-8493-

0474-1, (1993).

[4] NIOSH Manual of Analytical Methods, 4th Edition., 7300, U.S. Department of Health

and Human Services, Publ. (NIOSH), (1994).

[5] NIOSH Pocket Guide To Chemical Hazards, DHHS (NIOSH), U.S. Department of

Health and Human Services, Publication No. 97-140, (June 1997).

[6] 2002 TLV’s and BEI’s, ACGIH Worldwide, ISBN: 1-882417-46-1, (2002).

[7] Environment Protection Agency,40 CFR Ch. 1 (7-1-91 Edition), Part 136, Appendix B

[8] Harrison, G R “MIT Wavelength Tables”, Vol. 1, 2nd Edition, ISBN: 0-262-

08002-8, (Aug. 1969).

[9] Furr, A K “CRC Handbook of Laboratory Safety”, 4th Edition, CRC Press, Boca Raton,

Florida, (1995).

[10] Kennedy et.al “Guidelines for Air Sampling and Analytical Method Development and

Evaluation”, U.S. Department of Health and Human Services, Publ. (NIOSH),

(May1995).

Written By: Lee C. Stone, John M. Reynolds, James B. Perkins, and David M. Rogers, 

DataChem Laboratories, Salt Lake City, Utah under NIOSH Contract CDC-200-2001-

08000