United States
 Environmental Protection
 Agency
Environmental Monitoring
Systems Laboratory
Cincinnati, OH 45268
 Research and Development
EPA/600/S4-89/011 Sept. 1989
 Project Summary

 USEPA Method Study 38
 SW-846  Method 3010
 Acid Digestion of Aqueous
 Samples and Extracts for Total
 Metals for Analysis by  Flame
 Atomic Absorption
 Spectroscopy
 K.W. Edged and D.M. Wilbers
  An interlaboratory  method
validation study was conducted on
SW-846 Method 3010, "Acid Digestion
of Aqueous Samples and Extracts for
Total Metals for Analysis  by Flame
Atomic Absorption Spectroscopy," to
determine the mean recovery and
precision for analyses of 21  trace
metals in surface and wastewaters.
SW-846 Method  3010 includes
instructions for quality control,
sample preparation, and analysis of
samples by flame atomic absorption
Spectroscopy (FLAA).
  The study  design was based upon
Youden's non-replicate  plan for
collaborative tests of analytical
methods. Four water matrices were
spiked with  21 trace metals at six
concentration  levels, as three
Youden pairs. Nine  laboratories
digested and refluxed the spiked
water matrices with concentrated
nitric acid, brought them to volume
with dilute  hydrochloric acid, and
analyzed each for 21 trace metals by
FLAA. The primary objective of the
study was  to analyze  the results
using USEPA computer programs
entitled "Interlaboratory  Method
Validation  Study" (IMVS) which
produced measures of recovery and
precision for the 21 trace metals and
compared the performance of the
method between water types.
 Two additional studies were also
conducted on Method 3010. One
study compared minimum detection
limits (MDLs) reported in the SW-846
method manual to MDLs determined
using Method 3010. Another study
was conducted to verify that the
lowest concentration levels of the
optimum range given in the SW-846
method manual are valid. Comparison
between the samples at the lowest
concentration level specified in SW-
846 and  another sample at 50% that
value were  performed for  mean
recovery, overall  precision, and
single-analyst precision.
 The studies were conducted by The
Bionetics Corporation  under the
direction of the Quality Assurance
Research Division, Environmental
Monitoring  Systems  Laboratory,
Cincinnati, OH under Contract No. 68-
03-3254. Analytical work was
completed as of November 30, 1987.
The  report covers a period from
September 10, 1986 to February 28,
1988.
 This Project Summary was
developed by EPA's Environmental

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Monitoring  Systems  Laboratory,
Cincinnati,  OH,  to  announce  key
findings of the research project that is
fully documented in a separate report
of the same  title  (see Project Report
ordering information at back).


Introduction
  The  Hazardous  Waste Management
Facility Permit Regulations were  promul-
gated in  July, 1982 (40  CFR 265) and
provide performance standards  for the
monitoring of ground waters,  wastewaters
and  solid wastes  at  hazardous waste
sites. To facilitate these  standards,
certain  analytical  methodology  are
required to assess the degree of contam-
ination at  and  around the area of the site.
The Manual: Test Methods for Evaluating
Solid Waste,  Physical and Chemical
Methods,  (SW-846), November 1986,
Third Edition,  provides a unified, up-to-
date source of information on sampling
and analyses  related to compliance with
Resource Conservation and Recovery Act
(RCRA) regulations.  The  success of
these  pollution   control  activities,
particularly when legal  action is involved,
depends  upon the  reliability of the  data
provided by the laboratories.  Therefore, it
is important to evaluate the methodology
through interlaboratory  method validation
studies.
  The Environmental Monitoring Systems
Laboratory,  Cincinnati,  OH  (EMSL-
Cincinnati) develops or selects analytical
methods  and  provides  quality assurance
(QA)  support for Agency  programs
involving  water   and  wastewater
regulations.  In  EMSL-Cincinnati  the
responsibility  for  providing support is
assigned  to  the  Quality  Assurance
Research Division (QARD). Its program is
designed  to  provide  the  QA support
needed to  establish the   reliability and
legal  defensibility  of  water   and
wastewater data collected by the Agency,
the  state  regulating  authorities, the
private  sector,  and   commercial
laboratories  performing  compliance
analyses. One of QARD's QA activities is
to  conduct  interlaboratory  method
validation  studies  to evaluate  analytical
methods  selected for  the  Agency's
operating programs such as the Office of
Solid Waste.
  This report describes an interlaboratory
method validation study  for  SW-846
Method  3010,  "Acid  Digestion of
Aqueous  Samples and Extracts for Total
Metals for  Analysis by  Flame  Atomic
Absorption  Spectroscopy."   The
elements: aluminum, antimony,  barium,
beryllium, calcium,  cadmium, chromium,
cobalt, copper,  iron,  lead, magnesium,
manganese,  molybdenum,  nickel,
potassium,  silver,  sodium,  thallium,
vanadium, and zinc were analyzed using
Method 3010.
  The primary objective of the study was
to  characterize  the behavior of Method
3010  in terms of recovery, overall  and
single-analyst precision, and the effect of
water type on  recovery and precision.
The  study  was  conducted  with  the
cooperation  of  nine  participating
laboratories under the direction of the
Quality  Assurance Research  Division,
EMSL-Cincinnati.   The  Bionetics
Corporation,  as primary contractor to
QARD, was responsible for the collection
and  characterization  of  the water
matrices, preparation  of  analyte  spiking
solutions, preparation of user instructions
and report forms, distribution of samples,
and screening the returned data for gross
errors. The  raw data  were  evaluated
statistically by the QARD using a series
of  computer  programs entitled, "Inter-
laboratory Method  Validation  Studies"
(IMVS).  Upon review  of  the draft report
by  EMSL-Cincinnati,  The  Bionetics
Corporation prepared the  final report.
  A second objective of the study was to
compare the  minimum detection limits
(MDLs) reported in the SW-846 method
manual to the MDLs determined for the
21  elements  using Method 3010.  The
MDL for each element was obtained by
measuring the noise level  response for
seven reagent water digestates with no
detectable background. The mean  and
standard deviation of  the noise  level
responses were then  calculated.  Then,
each  of  the  four water matrices  was
digested  and  used to prepare  a  5  point
calibration curve by the  Method of
Standard  Additions.  The  MDLs were
calculated using the  following relation-
ship:
           MDL = 3(SD)/m
where,
  m     =  (y-i)/x  =   slope  of  the
           calibration curve
  x     =  concentration (ug/mL)
  y     =  signal at concentration x
  i      =  intercept of the  calibration
           curve
  SD   =  standard  deviation  of  the
           noise level responses
  A  third  study objective was to verify
that the lowest concentration levels of the
optimum range specified in the SW-846
method manual are valid. Comparison
between the  samples  at the  lowest
concentration level and another sample at
50% that value was performed for mean
recovery,  overall precision and single-
analyst precision.
Description of Study


Method Summary
  In SW-846   Method 3010, 100 mL
sample is  digested  with  3 mL
concentrated  nitric acid, evaporated
about 5 mL on a  hot plate, then cor
bined with 3 mL concentrated nitric ac
and refluxed. After cooling,  1:1  hydr
chloric acid is added. The sample is thi
diluted to 100 mL with Type II water. Tl
sample is then ready for  analyses f
aluminum, antimony, barium, berylliui
cadmium, calcium, chromium, coba
copper, iron,  lead, magnesium,  ma
ganese, molybdenum,  nickel, potassiui
silver,  sodium,  thallium,  vanadium, ai
zinc  by flame atomic absorption  spe
troscopy (FLAA).
Study Design
  The  study  design  was  based <
Youden's  non-replicate  design  f
collaborative evaluation of an  analytic
method  at  several concentration  leve
over its linear range.  According
Youden's design, two similar yet differs
samples are analyzed in pairs  such  ti-
the concentration  of the pairs vari
between 5 and 20 percent of the mean
the pairs. For this study, six concentrati
levels, as three Youden pairs, were us
(designated  samples  1  - 6). The anal^
was directed to do a single  analysis
each sample and report one  value 1
each element.  Analyses in reagent wa
evaluated the proficiency of  the meth
on  a sample  free  of interference
analyses in the other matrix waters we
intended to  reveal  the  effects
interferences on the method.
  The primary  contractor  prepared t
study samples  by  spiking measur
amounts of  standard  solutions  into t
matrix waters being  tested. Each spik
matrix water was then dispensed  ir
replicate 120 mL bottles for distribution
participants.  The analysts were instruct
to quantitatively remove a 100 mL aliqi
from each sample bottle for digestion a
analysis. A  matrix blank and  a qual
control  sample,  included in the stuc
were digested  with six  samples for ea
water type.  Background  concentrati
levels found in the matrix blanks  we
subtracted from the  total  concentrati
found in each  sample.  Acceptance lirr
were  provided for  the quality  cont
samples to verify  that  the analytii
system  was in control. If not in  conti
the problem was to be  corrected  a
fresh aliquots of the samples, associal

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with that QC sample, had to be digested
 nd reanalyzed.
  Spiking solutions were provided for the
MDL  phase  of the  study.  These
concentrates were used to spike aliquots
of the digested matrix waters by  the
Method  of Standard Additions.
  Finally, an  additional Youden sample
pair, designated 7-8, was included in  this
study. These samples were prepared at
50%  of the  concentration  level  of
samples 5-6, which were at the lowest
concentration  level of  the  optimum
working  range specified in  SW-846.
Digestion and analyses  of these samples
were  to  proceed  the  same  as for  the
regular six samples.

Verification Analyses
  To  assure  that the spiking  solutions
were  properly  prepared,  they  were
analyzed  using  freshly  prepared
standards before  being  spiked into  the
test waters. A set of spiked test waters
was  then digested and submitted  to
QARD analysts to verify sample integrity.
These analyses confirmed the  accuracy
of the distributed samples.


Selection of Test Waters
  The four test waters  selected for  this
study were reagent water, as the control,
Ohio  River  Water,  an  electroplating
company effluent  and a  municipal
sewage  treatment  plant  secondary
effluent.
  Each  test water was preserved, at the
time of collection, by adjusting the pH to
below 2.0. Prior to dispensing, each test
water was thoroughly mixed to ensure
homogeneity.  Aliquots  were removed
from each, digested  according to Method
3010, then sent to  QARD analysts  for
Inductively  Coupled  Plasma Spectros-
copy  analyses  to determine the back-
ground  concentrations of  the  21
elements covered in this study.

Selection of Participating
Laboratories
  The Quality Assurance  Research
Division  of EMSL-Cincinnati selected  the
participating  laboratories. As  per  the
standard  competitive  bid process, an
abstract of  the  scope  of  work  was
announced in  the Commerce Business
Daily.  Interested laboratories were for-
warded the complete request for proposal
(RFP) which  included  the evaluation
criteria upon which the  offerer would be
scored.
  The submitted technical  proposals
were  evaluated based  upon  laboratory
experience and quality control practices.
Laboratories  whose  proposals  were
acceptable were evaluated  further  in a
preaward  performance evaluation study.
The  participants selected for the formal
study were  the nine  laboratories  with
acceptable  proposals who  performed
best in the preaward study.


Results and Discussion
  The primary  objective of this study was
to characterize  the performance of  SW-
846  Method 3010 in  terms  of recovery,
overall precision, single-analyst precision
and the  effect of water type on recovery
and  precision.  The statistical results for
each   of   these   performance
characteristics will  be discussed below.

Rejection of Outliers
  In this study,  the  IMVS program
rejected a total of 995  data points  or
21.9% of the 4536 data points submitted.
Reagent water  had the lowest number of
rejected data with  195.  The number of
rejected data was higher for the other test
waters but  did not  vary significantly
among  the waters.  The  number  of
rejected data were 279  for  Ohio  River
Water, 258 for municipal  secondary
effluent,  and   263 for  electroplating
effluent. For a  single  element, across all
water types, the number  of rejected data
ranged from a  low of 25 for thallium to a
high of 78 for beryllium. For purposes of
this report, an element was considered to
have excessive outliers if its total number
of rejected data was equal to or greater
than 54 (25% of the total submitted data).
Using this criterion, the  following  eight
elements fell into this category: aluminum
(57), beryllium (78), chromium   (56),
cobalt (54),  molybdenum (54),  sodium
(58), vanadium (61), and  zinc   (72).
Laboratory 6 had the highest number of
rejected data with 234 while Laboratory 7
had the  lowest  number of rejected  data
with 27.

Mean Recovery
  The mean recoveries were calculated
for the 21 elements in each water type by
inserting  the midpoint concentration  of
the range studied into the mean recovery
equations  given in Table  1.  For  reagent
water the  percent recoveries for the 21
trace metals were excellent, ranging  from
91% to 108%, with silver (44%) being the
only exception.  For all  waters,  the
recoveries ranged from  94% to 109%
with  barium  (74%) and silver (28%) as
the exceptions.
  A  look  at  the barium  recovery
estimates shows  excellent  results for
reagent water  (97%)  and Ohio  River
Water  (98%)  but  extremely  poor
recoveries for the municipal  secondary
effluent (60%) and  the electroplating
effluent (42%). It was theorized that sulfur
oxides were present  in  the later waters
causing barium  to precipitate as  the
sulfate.
  Low silver  recoveries, i.e.,  as low as
9%, were reported in all water types.  The
percent recoveries of silver in  reagent
water showed acceptable recovery for the
low Youden pair samples, 98% and 96%,
with a significant decrease in  percent
recovery with increasing concentrations.
This indicates a solubility  problem  with
silver at higher concentration levels.

Precision
  The mean overall  precision  for all
metals,  expressed as  %RSDs, across
water  types,  ranged  from  2.9%  for
thallium to 13.9% for calcium  with  two
exceptions, barium  (31.2%)  and  silver
(65.7%). The poor silver precision  was
observed  in all water  types while  the
barium  precision  was  acceptable  for
reagent water (13.9%)  and  Ohio River
Water (12.0%) and poor for the municipal
secondary effluent  (31.6%) and  the
electroplating  effluent (67.2%).   The
%RSDs in reagent water  ranged from
2.6%  (thallium) to 13.9%  (barium)  with
the exception of silver (52.6%).
  The single-analyst  precision  for all
metals, expressed as %RSD-SRs, across
water types, ranged from 1.6%  (copper)
to 7.6% (calcium) with  two exceptions,
barium (15.2%) and silver (37.4%).  The
poor  single-analyst precision for  silver
was observed in all water types while the
barium  precision  was  acceptable  for
reagent water (6.5%)  and Ohio  River
Water (8.4%) and poor  for the municipal
secondary effluent  (16.9%) and  the
electroplating  effluent (28.8%).   The
%RSD-SRs for all elements  in reagent
water ranged from 1.2% (nickel) to 8.0%
(calcium) with silver  30.9%   being  the
only exception.

Effects of Water Type
  The recovery and precision estimates
across water types were subjected to an
analysis of variance test to determine the
effect water type had on the results. Nine
elements:  calcium, cobalt,  iron,  man-
ganese, molybdenum, sodium, antimony,
zinc,  and  barium  were  found  to have
statistically significant matrix effects  that
were  of  practical  significance  when
compared  to  reagent water.  Lead  was
also  found  to   have   a  statistically
significant  matrix effect  but  this  was not
considered to be of practical significance.

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Practical significance was determined by
a review of the retained data and judging
whether the statistically significant matrix
effects are influenced by the retention of
errant data  points or  non-uniform
recovery of one of the  Youden sample
pairs. If no anomalies  are found, the
effect was considered to be of practical
significance. The effect of water type on
analyses for silver was  not evaluated
because  of the  poor  recovery  and
precision results obtained.


Method Detection Limits (MDLs)
  Method detection limits  (MDLs) were
experimentally determined in the four test
waters by nine participating laboratories.
The  MDL for  each element in  reagent
water was  compared  with the MDLs
found in the  SW-846 method  manual.
This  comparison  showed  for  the
elements: barium,  molybdenum,  cobalt,
copper, nickel, and thallium, MDLs in this
study were 1 to 1.5 times higher than the
SW-846 MDLs. The  MDLs  for  elements
aluminum,  beryllium,  calcium,  iron,
magnesium, antimony, vanadium, silver,
cadmium, chromium, manganese, lead,
and zinc were  2 to 3 times higher than
the  SW-846  MDLs.  The MDL for
potassium was one fifth of the  SW-846
MDL while the MDL for sodium  was 7.5
times higher than the SW-846 MDL.

Evaluation of Lowest
Concentration Levels
  The final objective of this  study was  to
verify that the  lowest concentration levels
specified in  the SW-846 method manual
are obtainable. Comparison between a
sample  at   the  lowest  specified
concentration  level with  another sample
at 50% of that concentration level was
performed for mean recovery,  overall
precision  and single-analyst  precision.
The net changes in the mean recoveries
were compared in  reagent  water for the
21  elements. The  average  percent
recovery  for the  sample  at  50%
concentration  level was only 3.0% lower
than the average percent recoveries  at
the lowest concentration  level  specified
by the SW-846 method  manual.  Twelve
elements:  aluminum, calcium, cobalt,
chromium,  copper,  iron,  magnesium,
sodium, nickel, lead, vanadium,  and
barium had  less than  ±  5% net change
in percent recovery.  Six elements:
beryllium, cadmium, manganese,  anti-
mony, zinc, and  potassium had a net
change between  ±  (5%   - 10%). For
molybdenum  and  thallium, the  percent
recoveries for the 50%  concentration
levels were  19.6%  and 16.7% lower,
respectively,  than the percent recoveries
for the lowest concentration specified in
SW-846.  Silver had a  mean  recovery
17.4% higher, for the 50% concentration
level,  when compared to the  specified
concentration.
  The average overall  %RSD for  the
sample at 50% the method concentration
level was 4.9% higher than the average
overall %RSD at the lowest concentration
specified  in the SW-846 method manual.
Fourteen  elements: aluminum, calcium,
cobalt,  chromium,  copper,  iron,
magnesium, molybdenum, sodium, lead,
vanadium, zinc, barium, and  potassium
had a net change in  %RSD of less than
±  5%.  Five  elements:  beryllium,
cadmium,  manganese,  nickel,  and
antimony  had  a net change  in  %RSD
between  ±  (5% -  10%).  The  overall
%RSD for silver and  thallium at the 50%
concentration level  was  14.0%  and
26 9%  respectively, higher than  the
%RSDs at the lowest specified SW-846
concentration.
  The average  single-analyst  precision
for samples  at  50%  the concentration
level, was 0.9% higher than the samples
at the lowest concentration level specified
in SW-846. Twelve elements:  aluminum,
antimony,  barium,  beryllium,  cadmium,
cobalt,  copper,  magnesium,  potassium,
silver,  sodium, and  thallium  had  net
changes  less than  ±  5%.  Seven
elements: calcium,  chromium,  lead,
manganese, nickel, vanadium,  and zinc
had net changes between ±  (5% - 10%).
For iron  and  molybdenum, the  single-
analyst precision was 11.8% and 15.4%
higher,   respectively,  for the  50%
concentration level sample.

Conclusions
  The primary objective of this study was
to  characterize the performance  of
Method 3010 in terms of recovery, overall
precision,  single-analyst precision, and
the effect of water types on recovery and
precision.  Through the  IMVS computer
programs, statistical analyses of 4536
analytical values provided estimates  of
recovery  and  precision expressed  as
regression equations which are presented
in  Table  1.  These  equations may  be
used  to  predict the  recovery  and
precision  of  the 21  elements  over  the
range tested.
  The IMVS programs rejected 995 data
points (21.9%) of  the 4536  data points
submitted. The percentage of rejected
data did not vary significantly among the
water types,  ranging  from  20%  for
reagent  water to  28%  for  Ohio River
Water. Thallium had the fewest rejected
data with 15 while beryllium had the mo
with 78. The number of rejected data t
laboratory  ranged from 27 for  Lab 7
234 for Lab 6. The rejected data were n
evenly  distributed  among   th
laboratories.  Labs  3, 4,  6 and
accounted  for  624 of  the 995  tot
rejected data (62.7%).
  Recovery  estimates for  the  2
elements were calculated at the midpoii
concentration  of the range studied usiri
the regression equations in  Table 1. Th
average percent recovery of all elemen1
across all  water types  were  excellei
ranging  from  94% to  109%  with  tw
exceptions, silver  (28%)  and bariui
(74%).
  Silver recoveries were concentratio
dependent. The  silver concentratio
range used in this study was 0.10 to 4.
ug/mL as recommended in  the SW-84
method  manual. In  reagent water th
percent  recoveries of the  low sampl
concentration  pair, 0.10 and 0.15  ug/m
were  97.8%  and 95.6% respectively
However,  as  the concentration  level
increased  the  percent  recover
decreased   dramatically to  20%  at th
4.0 ug/mL  concentration level. Thes
findings support the  conclusions  c
Hinners, EMSL-Las Vegas, as reference'
in the main report.
  Barium  recoveries  were  good  ii
reagent water  (97%)  and  Ohio Rive
Water (98%),  but were poor in municipj
secondary  effluent  (60%)   am
electroplating  effluent  (42%). It  wa
theorized that  the presence  of  sulfu
oxides in the later two  water  matrice
caused  the  barium to  precipitate a
barium sulfate.
  For all metals,  the  overall  standart
deviations  expressed  as %RSD,  wer<
good. Across  all water types  the rang*
was from 3% to 14% with the exception:
of  silver (66%)  and barium (31%).  Thi
high silver variability was observed in  al
four test waters while the barium %RSE
was  high  in  the  municipal  secondary
effluent (32%)  and the electroplating
effluent (67%), and low in reagent wate
(14%) and  Ohio  River Water (12%).
  The single-analyst standard deviations
expressed  as %RSD-SR,  were  good
Across all water types  the range  wa:
from 2% to 8% with  the exceptions  o
silver (34%) and barium (15%). The higt
silver variability  was observed  in all fou
test waters while the barium %RSD-SF
was  high  in  the  municipal  secondary
effluent  (17%) and electroplating effluen
(29%) and low in reagent water (6%) anc
Ohio River Water (8%).
  Statistical comparisons were performed
on all elements to determine if there were

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 Affects due to water type. The statistically
  gnificant matrix effects for calcium,
 jobalt,  iron, manganese, molybdenum,
 sodium,  zinc,  silver  and barium were
 ound to be of practical significance. The
 statistically significant matrix effects were
 lot  considered  to  be of  practical
 significance for lead and antimony. The
 silver statistics were too variable to draw
 my conclusions.
  Method detection  limits (MDLs) were
 ietermined  experimentally  by nine
 aboratories on 21 elements in the four
 est  waters.  In  reagent  water,  the
 ixperimental   MDLs   for   barium,
 nolybdenum, cobalt, copper, nickel, and
 hallium  were  equivalent to  the SW-846
 nethod manual MDLs (1  to 1.5 times the
 5W-846 MDLs). Aluminum,  beryllium,
 :alcium,  iron,  magnesium, antimony,
 'anadium,  silver, cadmium, chromium.
 nanganese, lead, and zinc  had MDLs 2
 o 3  times higher than those reported in
 ie SW-846 manual. Potassium was one
 ifth  lower and  sodium  was  7 5  times
 ugher than the SW-846 MDLs. Except for
 lOtassium  and   sodium, the experimen-
 ally determined  MDLs  in this  study
 ipproximated the MDLs reported in SW-
 46.
  The  analyses of the additional Youden
 ample pair indicated that Method 3010
 an  be used to  analyze elements at a
 :oncentration  level  50%  lower than
 ecommended  in  SW-846 with  a
 ecreased in recovery on the average of
 1.0%  and a  decrease  in  overall and
 •ingle-analyst precision on the average of
 .9% and 0.9%, respectively.

 Recommendations
  SW-846 Method 3010 is recommended
 or the analysis  of  aluminum, beryllium,
 :alcium,  cadmium,  cobalt,  chromium,
 :opper,  iron, magnesium,  manganese,
 nolybdenum,  sodium,  nickel,  lead,
 antimony, thallium,  vanadium, zinc, and
 Dotassium in  wastewaters.  The  linear
 •egression equations  obtained from  this
 study,  and presented  in Table 1, can  be
 jsed to predict the  mean  recovery,
 overall  precision  and  single-analyst
 Drecision  of these elements at concen-
 rations in the ranges  investigated in this
study.
  Statistical  review  of  barium  data
revealed low recovery and poor precision
(high variability)  in  municipal  secondary
effluent and electroplating  effluent  but
good  recovery  and  precision   from
reagent  water and Ohio River Water.
Precipitation reactions involving barium
  ilfate have been hypothesized for these
.natrix  effects.  Analysts are  cautioned to
interpret  barium data carefully from  any
water matrix.
  The mean recovery of silver was found
to decrease significantly with increasing
concentration in the range studied (0.1 -
                   4.0 ug/mL). These findings,  as well as
                   those of Hinners, suggest  that  further
                   investigation  into the optimum  working
                   range  for  silver  analyses  is  recom-
                   mended
Table 1.   Study 38,  SW 846 Method 3010. Trace Metals, AA  Flame Weighted Linear
          Regression Equations for Mean Recovery and Precision (in
Water Type
   Aluminum, Al
Beryllium, Be
  Calcium, Ca
Applicable Cone. Range
Reagent Water
Single-Analyst Precision
Overall Precision
Mean Recovery

        Water 1
Single-Analyst Precision
Overall Precision
Mean Recovery

        Water 2
Single-Analyst Precision
Overall Precision
Mean Recovery

        Water 3

Single-Analyst Precision
Overall Precision
Mean Recovery
   (5.00 - 50.00)
(0.04 - 2 00)
(18.00 - 120.00)
SR = 0.054X + 0.17 SR  = 0.019X + 0.01  SR = 0097X - 0.87

 S=0.086X-002   S=0.118X + 000   S = 0.117X - 0.02

 X = 1.026C -0.29   X = 0.913C + 000  X = 1 001C + 2.12


 SR = 0.02X  + 0.09 SR  = 0020X * 0 00  SR = 0.105X - 0.71

 S = 0.071 X - 0.07    S  = 0.054X -000    S = 0 200X - 2.41

 X = 0.947C - 0.25   X = 0.951C +000   X = 0.938C - r.36


SR = 0021X + 0.08 SR  = 0.032X + 0 00 SR = 0.018X  + 2.46

 S = 0026X  + 037  S = 0.048X + 0.00  S = 0.122X + 1.29

 X = 0.993C -032   X = 0.966C + 000  X = 1 051C + 0.97


 SR = 0.024X -002 SR  = 0.020X + 0 00 SR = 0.016X  + 2.67

 S = 0.036X  + 006  S = 0.038X + 0.00   S = 0./67X -095

  X = 1 019C -021   X -0.967C + 0.00   X =08940 + 228
Water Type
        Cadmium, Cd
               Cobalt, Co
Applicable Cone. Range

Reagent Water

Single-Analyst Precision
Overall Precision

Mean Recovery

Water 1
Single-Analyst Precision
Overall Precis/on

Mean Recovery

Water 2

Single-Analyst Precis/on
Overall Precision

Mean Recovery

Water 3

Single-Analyst Precision

Overall Precis/on

Mean Recovery
        (0 04 - 2.00)


     SR = 0017X  +000

     S = 0 029X +000

     X = 0.993C •*• 0.00


     Sfl = 0.016X  + 000

     S = 0 034X + 000

      X = 0 989C - 0 00



     SR = 0.022X  +000

     S = 0.042X +001

     X = 0.988C +000



     SR = 0019X  +000

     S = 0 029X + 0.01

     X = 1.001C + 0.00
             (2.50 - 15.00)


           SR = 0.032X - 0.05

           S = 0 066X - 0.07

           X = 0985C  + 0.01


          SR = 0.015X + 0.06

           S = 0.086X  + 0.00

           X = 0.992C - 0.09



          SR = 0.014X + 021

           S = 0 056X  + 0.20

           X = 0.967C  + 0.39



           SR = 0.031 X -0.04

           S = 0.044X  + 0.08

           X =0.990C  - 0.05
X   =   Mean Recovery
C   =   True Value for the Concentration
Water \  =   Ohio River Water
Water 2  =   Municipal Secondary Effluent
Water 3  =   Electroplating Effluent

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Table 1. (Continued)
Water Type	
   Chromium, Cr
    Copper, Cu
      Iron, Fe
  Magnesium, Mg
Applicable Cone. Range
Reagent Water
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 1
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 2
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 3
Single-Analyst Precision
Overall Precision
Mean Recovery
   (0.50 - 10.00)

SR = 0.0J9X + 0.06
 S = 0.090X + 0.01
 X = 1.082C - 0.03

 SR = 0.030X - 0.00
 S = 0.079X + 0.03
 X = 1.093C + 0.02

SR = 0.027X + 0.03
 S = 0.077X * 0.03
 X = 1  116C-0.06

SR = 0.034X + 0.00
 S = 0.088X + 0.07
 X =1.077C-0.02
    (0.20 - 5.00)

SR  = 0.012X + 0.07
 S = 0.030X + O.OT
 X = 0.997C + 0.00

 SR = 0.024X - 0.00
 S = 0.026X + 0.01
 X = 0.988C + 0.00

SR  = 0.010X + 0.00
 S = 0.022X + 0.0?
 X = 0.993C + O.Or

 SR = 0.016X -0.00
 S = 0.036X + 0.01
 X =0.997C + 0.00
    (0.30 - 5.00)

SR  = 0.010X + 0.05
 S = 0.051X + 0.03
 X = 0.955C + 0.01

SR  = 0.031 X + 0.06
 S = 0.058X + 0.10
 X  = 0.962C -0.12

SR  = 0.002X + 0.08
 S = 0.027X + 0.10
 X  = 0.985C - 0.05

SR  = 0.026X + 0.04
 S = 0.075X + 0.06
 X  = 7.065C - 0.75
   C5.00 - 40.00)

 SR = 0.022X - 0.03
 S = 0.058X - 0.24
 X = 7.027C - 0.02

SR = 0.009X + 0.22
 S = 0.020X + 0.35
 X = 1.018C - 0.10

 SR = 0.072X-0.70
 S = 0.059X + 0.07
 X = 1 021C - 020

SR = 0.014X + 0.08
 S = 0 034X - 0.00
 X =1.011C -  0.03
Water Type
  Manganese, Mn
  Molybdenum, Md
    Sodium, Na
     Nickel, Ni
Applicable Cone. Range
Reagent Water
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 1
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 2
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 3
Single-Analyst Precision
Overall Precision
Mean Recovery
    (0.10-3.00)

SR  = 0.020X + 0.01
 S = 0.030X + 0.01
 X = 1.019C + 0.01

SR  = 0011X + 0.00
 S = 0.020X + 0.02
 X  = 1.008C -0.01

SR  = 0.006X + 0.01
 S = 0.027X + 0.07
 X  = 0.987C - 0.00

SR  = 0.020X + 0.00
 S = 0.048X + 0.00
 X  = 7.024C + 0.00
   C7.00 - 40.00;

SR = 0.064X + 0.25
 S = 0.107X + 0.22
 X = 1.031C -0012

 SR = 0.058X - 0.01
 S = 0.111X - 0.05
X =  1.011C + 0.019

SR = 0.049X + 0.02
 S = 0.143X -0.07
X =  1.051C + 0.107

SR = 0.043X + 008
 S = 0.123X -0.02
 X = 7.002C +  0.043
  (96.00 - 600.00)

 SR = 0.038X - 1.82
 S  = 0.068X - 0.42
 X  = 1 025C - O.J7

 SR = 0.025X - 0.80
 S = 0.038X +  0.37
 X = 0.986C +  2.44

 SR = 0 066X - 2.56
 S = 0.066X +  2.03
 X  = 0.991C- 1.80

SR  = 0050X •*• 0.74
S = 0.033X + 11 92
 X  = 0.988C-8.97
    (0.30- 5.00;

SR = 0.004X + 0.02
 S = 0.029X +  0.03
 X = 0.997C - 0.07

SR = 0075X + 0.01
 S = 0.051X - 0.00
 X = 0 997C - 0.07

SR = 0 026X + 0.03
 S = 0 032X +  0.05
 X = 1.020C - 0.02

SR = 0.008X + 0.04
 S = 0 034X +  002
  X =1 011C - 0.01
X    =   Mean Recovery
C    =   True Value for the Concentration
Water 1  =   Ohio River Water
Water 2  =   Municipal Secondary Effluent
Water 3  =   Electroplating Effluent

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Table 1. (Continued)
Water Type	
      Lead, Pb
   Antimony, Sb
     Thallium, Ti
    Vanadium, V
Applicable Cone. Range
Reagent Water
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 1
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 2
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 3
Single-Analyst Precision
Overall Precision
Mean Recovery
Reagent Water
Single-Analyst Precis/on
Overall Precision
Mean Recovery
           Water 1
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 2
Single-Analyst Precision
Overall Precision
Mean Recovery
           Water 3
Single-Analyst Precision
Overall Precision
Mean Recovery
    (0.80 - 20.00)

SR = O.OT8X + 0.03
 S = 0.079X + 0.09
 X = 7.037C -0.02

SR = 0.028X + 0.05
 S = 0.047X + 0.07
 X = 7.023C + 0.04

SR = 0.030X + O.OT
 S = 0.046X + 0.05
 X = 1 046C - 0.08

 SR =  0.047X - 0.02
 S = 0.082X - 0.04
 X =0976C + 0.03
   (1.20 - 40.00)

SR = 0.023X + 0.19
 S = 0.044X + 0.20
  X = 1.057C-0.25

SR = 0.03TX + 0.70
 S = 0066X + 0.72
 X = 7.055C - 0.22

Sfl = 0.077X + 0 74
 S = 0 039X + 0.79
 X = 1.049C -0.11

SR = 0.003X + 007
 S = 0.006X + 0.19
 X = 1.050C + 0.01
   (1.00 - 20.00)

SR = 0.009X + 0.07
 S = 0.021X + 0.05
 X = 7.039C - 0.03

SR = 0.079X + 0.05
 S = 0.033X + 0.05
 X = T.028C - 0.04

SR = 0.076X + 0.01
 S = 0.017X + 0.06
 X = 1.028C -0.03

SR = 0.073X + 005
 S = 0 024X + 0.05
  X  =1.032C -001
   (2.25 - 99.00)

SR = 0.064X + 0.15
 S = 0.109X -0.02
X =  1.047C + 0.003

 SR = 0.045X - 0 06
 S = 0.099X -0.72
 X  = 1 052C  + 0.06

SR = 0.027X + 0.01
 S = 0.128X-0.14
 X = 1.056C - 0.08

SR = 0.011X + 0.03
 S = 0.079X - 0.04
 X = 1.055C * 0.03
Water Type Zinc, Zn
Applicable Cone. Range (0.10 - 1.00)
Silver, Ag Barium, Ba Potassium, K
(0.10- 4.00) (1.00 - 20.00) (4.80 - 30.00)
SR  = -0.009X + 0.01
 S = 0.035X + 0.01
 X = 0.984C + 0.01

SR  = 0.039X + 0.02
 S = 0.067X + 0.02
 X  = 0 983C - 0.06

SR  = -0.022X + 0.05
 S = -0 007X + 006
 X = 0.959C +002

SR  = 0.02 7 X + 0.02
 S = 0 026X + 0.02
 X = 0 953C + 0.00
 SR = 0.343X - 0.03
 S  = 0.583X - 0.05
 X = 0.402C * 0.07

 SR = 0.221X - 0.00
 S  = 0 765X - 0.04
 X = 0 172C + 0.07

 SR = 0.368X-003
 S  = 0.607X -005
 X = 0345C + 006

 SR = 0.979X -006
 S  = 0.956X -007
 X =0 058C + 0.06
 SR = 0 067X - 0.02
 S  = 0 742X - 003
 X = 0967C +005

 SR = 0 089X - 0.05
 S  = 0.127X -0.07
 X = 0970C + 0.07

 SR = 0.197X -0.17
 S  = 0361X -027
 X = 0.536C + 0.64

 SR = 0389X -0.42
 S  = 0.874X - 0.84
 X =0.329C + 0.86
SR = 0.072X + 0.38
 S = 0.080X + 0.02
 X = 0923C+ 0.75

SR = 0.069X + 0.00
 S = 0.113X -0.70
 X = 0.976C + 0.01

SR = 0.055X + 0.78
 S = 0.707X + 0.07
 X = 0.927C + 0.37

SR = 0.032X + 0.36
 S = 0.052X + 0.45
 X = 0.961C -0.06
X    =   Mean Recovery
C    =   True Value for the Concentration
Water ;   =   Ohio River Water
Water 2   =   Municipal Secondary Effluent
Water 3   =   Electroplating Effluent

-------
   K. W. Edgell and 0. M. Withers are  with The Bionetics Corporation, Cincinnati,
        OH 45246
   Edward L Berg is the EPA Protect Officer (see below).
   The complete  report,  entitled "USEPA Method Study 38 SW-846 Method 3010
        Acid Digestion  of Aqueous Samples and  Extracts  for  Total Metals  for
        Analysis by Flame Atomic Absorption Spectroscopy," (Order No. PB 89-
        181 945/AS; Cost: $21.95, subject to change) will be available only from:
            National Technical Information Service
            5285 Port Royal Road
            Springfield, VA 22161
            Telephone:  703-487-4650
   The EPA Project Officer can be contacted at:
            Environmental Monitoring Systems Laboratory
            U.S. Environmental Protection Agency
            Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
      BULK RATE
POSTAGE & FEES PAID
         EPA
   PERMIT No. G-35
Official Business
Penalty for Private Use $300
EPA/600/S4-89/011

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