&EPA
United States
Environmental Protection
Agency
Environmental Monitoring and
Support Laboratory
Cincinnati OH 45268
EPA-600/8-83-020
August 1983
Research and Development
Guidelines and
Format for
EMSL-Cincinnati
Methods
>
t§!tiRffi*l
sis
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EPA-600/8-83-020
August 1983
Guidelines and Format
for
EMSL-Cincinnati Methods
by
John F. Kopp
Physical and Chemical Methods Branch
Environmental Monitoring and Support Laboratory
Cincinnati, OH 45268
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY
CINCINNATI, OHIO 45268
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NOTICE
This document has been reviewed in accordance with U.S. Environmental
Protection Agency policy and approved for publication. Mention of trade
names or commercial products does not constitute endorsement or
recommendation for use.
ii
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Introduction
The following guidelines and format are to be used for preparation of EMSL-Cincinnati
methods. These guidelines, in general, follow the American Society for Testing and
Materials (ASTM) requirements as stated in "Form and Style for ASTM Standards,"
5th ed. June 1 980 (1 3-000001-80). A copy of this publication is available in the,
Physical and Chemical Methods Branch office. EMSL-Cincinnati Method 524
" Measurement of Purgeable Organic Compounds in Drinking Water by Gas Chromato-
graphy/Mass Spectrometry" has been prepared to conform to these guidelines and is
included for reference in Appendix A
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Part I - Format
1. Title
1.1 Use concise titles that include (in the following ;
sequence) the method number, the particular proper- j
ty or analyte being determined, the type of sample to
which the method is applicable, and the technique or
instrumentation. If the method is used to determine !
a number of analytes or properties, use a general
title, omitting the names of specific analytes or j
properties. ;
1.2 Examples of suitable titles are: \
Method239.1 LeadinWaterandWastewaterby |
Direct Aspiration Atomic Absorption !
Method 340.2 Fluoride in Water and Wastewater
Using an Ion Selective Electrode
Method 604 Phenols in Wastewater by Gas j
Chromatography
» Method 908.1 Uranium in Drinking Water by
Fluorometry \
2. Method Number
2.1 Assign to each method a three, four, or five digit i
number in the format XYY.Z, where X indicates the '
general analyte class, YY indicates a particular analyte '
or group of analytes, and Z indicates a particular ;
version or variation of a method. Z many be any
numberfromOto99. When Z is 0 it may be omitted.
An example of this system may be found in Methods :
for Chemical Analysis of Water and Wastes, EPA-
600/4-79-020. |
ED/TOR'S NOTE Authority for assigning method
numbers is the responsibility of the Writer-Editor
following recommendations from the appropriate
Branch and Section chiefs.
3. Cover Sheet and Index
3.1 The use of a cover sheet is optional. If used, list I
individual names to provide credit to the researcher j
andasourceofinformationtotheuser. Theessential
features of the cover sheet are: '
Method Number and Title
Date of Issue I
EPA Author, Project Officer, or Technical Editor :
with Address
Appropriate Branch and Section ;
Program Office or Contractor
Sponsoring Agency with Address ',
Performing Laboratory or Agency with Address
An example of a suitable cover sheet is included in
Appendix A
3.2 The use of an index is required for methods manuals (
and may be desirable for lengthy, single methods. If ;
so used, the index appears on the opposite side of
the cover sheet
4. Section Headings
4.1 Use of the following sequence. Unless asterisked, all
headings are considered mandatory for all methods.
SCOPE AND APPLICATION
SUMMARY OF METHOD
DEFINITIONS*
INTERFERENCES
SAFETY
APPARATUS AND EQUIPMENT
REAGENTS AND CONSUMABLE MATERIALS
SAMPLE COLLECTION, PRESERVATION AND
STORAGE
CALIBRATION AND STANDARDIZATION
QUALITY CONTROL
PROCEDURE
CALCULATION
PRECISION AND ACCURACY
REFERENCES*
Additional sections may be used as required by the
particular method.
4.2 Follow the Modified Decimal Numbering (MDN)
system in EMSL-Cincinnati method write-ups. The
object of this system is to assign to each method
section and subsection a unique number that will
show the relationship of a specific section to all
previous sections and will allow for easy reference.
4.2.1 Number the primary sections of a method
consecutively, begining with 1 (SCOPE AND
APPLICATION), using as many numbers as
required by the number of sections. Number
each subsection consecutively as 1.1, 1.2,
1.3, etc. Subsections may be further subdivided
as 1.1.1,1.1.2,1.1.3, but should be held to a
minimum.
4.2.2 Subsections may be given headings if they
will help the organization of the material.
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Part II - Style
1. Capitalization and Underlining
1.1 Designate SECTION HEADINGS with all capital
letters and underlining.
1 .2 Designate SECONDARYSUBSECTION HEADINGS, if
used, with all capital letters and no underlining.
1.3 When Tertiary Subsection Headings are used, de-
signate them with initial capitalization of major
words.
1 .4 Designate Lesser subsection headings with capitali-
zation of the first word only.
2. Footnotes and Notes
2.1 Do not use footnotes except in tables. Designate
these with lower case letters, and type them below
the body of the table.
2.2 Notes may be used within the text to provide sup-
plementary information that may be helpful but is
not always essential to the reader.
3. Tables aind Figures
3.1 Tables and figures should appear at the end of the
text and after the list of references.
3.2 Number tables and figures consecutively with arabic
numerals, and give each a title that is complete and
descriptive.
3.3 In table column headings, first specify the quantity
being tabulated. Use a comma to separate this from
the units of measurement (e.g. amount spiked,
3.4 Place figure titles below the information presented,
table titles above.
4. Trademarks
4.1 Avoid the use of trademarks whenever possible. For
example, use borosilicate glass rather than Pyrex or
Kimax.
4.2 When a trademark must be used, capitalize it When
in doubt capitalize.
5. References
5.1 Refer to other sections of the method with the
abbreviation "Sect" followed by the appropriate
numbers.
5.2 Do not incorporate essential information into the
method by referring to another method.
6. Units, Symbols and Abbreviations
6.1 Units and symbols from the international metric
system (SI, from the French name, Le Systeme
International d' Unites) are to be used. SI is based on
seven basic units that are dimensionally independent
The SI unit of time is the second (symbol = s) which
should be used if practical. The SI unit of volume is
the cubic meter (symbol = m), but the special name
liter (symbol = L) can be used for liquids and gases.
Although the SI unit for mass is kilogram (symbol =
kg), the use of gram (g) with or without prefixes is
appropriate.
6.2 Symbols are not followed by a period except when
used at the end of a sentence. Except for the symbol
for liter, L, unit symbols are written in lower case,
unless the unit name was derived from a proper
name, such as Pa, from Pascal. Symbols, not abbre-
viations, should be used for units. When a quantity is
expressed as a numerical value and a unit symbol, a
space should be left between them, except that no
space is left between the number and symbol for
degree Celsius (20°C) and for degree, minute, and
second of plane angle.
6.3 Use unit symbols and abbreviations in the singular
only. Exceptions: Figs., Nos., Eqs., Refs.
6.4 When a long word or phrase for which there is no
standard abbreviation is used frequently, it may be
replaced by an abbreviation that is explained when it
first occurs. Examples: belowtopdeadcenter(btdc),
relative centrifugal force (rcf).
6.5 Commonly accepted abbreviations for names of
societies, associations, government agencies, etc.,
may be used, provided the name is spelled out the
first time it is used. Use no periods and run together.
Examples: ASTM, ASME, TAPPI, NASA ARPA,
USEPA.
6.6 A list of some appropriate abbreviations is included
in Appendix B to this document.
7. Numbers
7.1 Spell out all numbers from one through ten, with the
following exceptions:
7.1.1 Use numerals when the quantity is partly
fractional, as: 1.1 5, 1 Vi.
7.1.2 Use numerals when followed by an expression
having a standard unit symbol, as: 1 m, 9%.
7.1.3 If for any reason the standard abbreviation or
unit symbol of the expression following the
number is not used, or if the expression does
not permit an abbreviation (as year, ton, etc.)
the use of numerals is optional, unless covered
in the following paragrapha
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7.1.4 In contrasting statements, if some numbers
must be numerals, use numerals for all, as "2
tests and 16 weighings."
7.1.5 Use numerals after abbreviations, as: Vol 26,
Fig. 2.
7.2 When a number is used as an adjective, use a hyphen
between the number and the unit of measure, i.e., 2-
mL pipet 10-mL volumetric flask etc.
7.3 Use numerals for all numbers exceeding ten, with
the following exceptions.
7.3.1 Do not begin a sentence with a numeral.
When the numeral is spelled out also spell out
the unit following, as "One gram is usually
sufficient"
7.3.2 Round numbers used in a indefinite sense
shall be spelled out: as, "Ahundred feet or so."
7.3.3 Spell out numbers when used in the following
manner: "fifteen 2-in. rods," (or 15 two-inch
rods).
7.4 When writing decimal numbers of value less than
one, place a zero before the decimal point
7.5 In pointing-off numbers of more than four figures,
use spaces instead of commas in the text illustrations,
and tabular matter (1 234 567). Do not point-off
numbers of four figures (1234) except in tables
when they occur in a column containing numbers of
more than four figures.
7.6 In expressing ranges and ratios, use 1 to 10 or 1:10,
not 1-10, except that a hyphen may be used for
ranges in tables to conserve space.
7.7 Significant Digits
7.7.1 Any digit that is necessary to define the
specific value or quantity is significant For
example, when measured to the nearest 1 m, a
distance may be 157 m, which has three sig-
nificant figures; when measured to the nearest
0.1 m, the distance may be 1 57.4 m, which
has four significant figures.
7.7.2 Handle numbers with careful regard for cor-
respondence between the data accuracy and
the given number of digits. The number of
significant digits should neither sacrifice nor
exaggerate accuracy. For example, the number
4 has much less implied accuracy then the
number 4.0000.
7.7.3 Zeros may be used to indicate a specific value
or to indicate the order of magnitude of a
number. For example, in the number
203 185 000, representing population rounded
to thousands, the first six digits are significant
The last three digits are zeros that indicate the
order of magnitude.
7.7.4 When adding or subtracting numbers with
different degrees of precision, the answer
should contain no significant digits farther to
the right than the least precise number. Num-
bers should first be rounded to one significant
digit farther to the right than that of the least
precise number. The answer is then rounded
to the same number of significant figures as
the least precise numbers.
7.7.5 For multiplication and division, the product or
quotient should contain no more significant
digits than are contained in the number with
the fewest significant digits.
7.7.6 Examples to distinguish the two rules are:
Multiplication:
113.2 x 1.43 = 161.876, rounded to 162
Division:
113.1 -H 1.43 = 79.16, rounded to 79.2
Addition:
11 3.2 + 1.43 = 114.63, rounded to 114.6
Subtraction:
11 3.1 - 1.43 = 111.77, rounded to 1 11.8
NOTE: The product and quotient above should
contain only three significant digits because
the number 1.43 contains only three signifi-
cant digits. The above sum and difference,
however, contain four significant figures, be-
cause digits that occur to the right of the last
significant digit in the least precise number
are rounded.
7.8 Rounding Numbers
7.8.1 When the first digit discarded is less than five,
the last digit retained is not changed.
7.8.2 When the first digit discarded is greater than
5 or 5 is followed by a digit other than 0, the
last digit retained is increased by 1.
7.8.3 When the first digit discarded is exactly 5
followed only by zeros, the last digit retained
is rounded upward if it is an odd number and
is not adjusted if it is an even number.
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Part III - Content
1. Scope and Application (Mandatory)
1.1 Include information on the purpose, application, etc.,
of the method. List analytes that will be measured,
the Chemical Abstracts Service Registry Numbers
(CASRNs), and those matrices for which the method
has been found satisfactory. Include STORET
numbers for all apalytes. Do not discuss the analytical
technique in thi$ section. If regulations cite other
than the most commonly used analyte name, refer to
that used in the regulation but do not refer to the
regulation. For pesticides, use "acceptable common
names." The use of registered trade names is
permitted.
1.2 I ndicate the statistically determined method detection
limit (M DL) and the analyte concentration range over
which the method is applicable. State in what matrix
or matrices the MDL was determined. If the MDL is
not available, report an instrumental detection limit
and define how it was derived.
1.3 Include appropriate comments on method limitations,
such as "This method is not applicable to saline
water," or "This method measures phenoxy acid
esters in combination but not individually." Indicate
any means of recognizing cases where the method
may not be applicable to the sample under test
Provide an estimate of how many samples can be
analyzed during an 8-h period, if known.
1.4 List any restrictions that may apply, such as "This
method is restricted to use by or under the super-
vision of analysts experienced in "
NOTE Subsection 1.1 and 1.2 are mandatory.
2. Summary of Method (Mandatory)
2.1 Include a brief outline of the method and the basic
steps involved. Describe in the passive voice the
essential features, but omit the details that are a
necessary part of the complete statement of pro-
cedure. (A brief statement of the principle of the
method may be given; this is particularly desirable
in the case of chemical methods and should appear
as the first subsection:) In chemical methods state
the type of procedure (colorimetric, electrometric,
volumetric, etc.) and describe the source of color,
major chemical reaction, including pertinent chemical
equations, etc. Similarily, for instrumental methods,
state the technique.
2.2 List options to the method, if applicable.
3. Definitions
3.1 Include here a statement referring the analyst to any
appended glossary.
3.2 No more than four definitions (or terms) may be
included in the body of the method. Additional
definitions should be given in an appended glossary.
4. Interferences (Mandatory)
4.1 List briefly the constituents or properties that are
likely to cause interference and the amounts that are
known to interfere. Sometimes, this information can
be obtained only by observation during the analysis.
In such cases, include appropriate notes under
"Procedure" or "Calculations."
4.2 Identify any substances or ions that are known to
either interfere or not interfere.
5. Safety (Mandatory)
5.1 Safety Precautions - When there are potential hazards,
such as explosions, fire, toxicity, or radiation, to
personnel who perform the test include a warning to
this effect Indicate the steps in the procedure where
these hazards exist At the point in the text where a
precaution is important include the word CAUTION
in boldface type, followed by the details of the
protective or precautionary measures to be taken.
EDITOR'S NOTE Input from the EMSL Safety Officers
should be obtained as to what should be included in
this section.
6. Apparatus and Equipment (Mandatory)
6.1 In this section, describe the essential features of the
required apparatus and equipment and include
schematic drawings where they are needed to clarify
or supplement the text Do not list common laboratory
apparatus, but do include special or modified forms
of unusual sizes or numbers of common apparatus
thatare required orthat may require special preparation.
6.2 Avoid the use of trademarks, etc., unless a specific
manufacturer's product is required for a well-defined
reason or if the availability of the product is limited. In
such cases, an explanatory note may be included
giving supplementary information regarding such
apparatus or equipment See Section 4.
6.3 When special types of glassware are required, such
as heat-resistant, chemical-resistant, etc., state the
significant characteristic desired rather than a trade-
mark. For example, use "borosilicate glass" rather
than Pyrex or Kimax. If only a single source is known,
that source may be identified.
6.4 Indicate any special glassware cleaning instructions.
6.5 List special facilities required such as a special room
for handling hazardous materials.
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7. Reagents and Consumable Materials
(Mandatory)
7.1 List reagents alphabetically in separate subsections. [
Give the name of the reagent first and the necessary;
purity, followed by any descriptive terms.
NOTE Reagents are to be ACS Reagent Grade u nless
otherwise specified.
For solutions, state the desired concentration followed'
by instructions for preparation and reference to any
necessary standardization, using the imperative mood
and concise descriptions. Spell out full name of j
inorganic reagents when first used, and include
within parentheses the exact chemical formula
showing its waterof crystallization, etc. Subsequently,;
refer to inorganic compounds by formula if they can
be clearly specified by this means. As exceptions,
always spell out the word "water" and the names of
substances in their elementary state; for example,
use lead, not Pb; oxygen, not02. Chemical formulae j
can be omitted in the case of organic, organo-;
metallic, or complex inorganic compounds. For these
materials give the CASRN to avoid any ambiguity. ;
7.2 Avoid the use of trademarks and names patented i
products, using chemical names only, unless a!
specific product is required for a well defined reason.
The use of registered trade names is permitted. !
7.3 If a different grade of reagent water otherthanASTM
Reagent Grade Water, Type II, is required, specify
the desired characteristics and how it should be
prepared. (Type II grade of reagent water shall be :
prepared by distillation using a still designed to I
produce a distillate having a conductivity of less than ;
1.0 /u mhos/cm at 298 K (25°C). Total matter may j
not exceed 0.1 mg/L) Ion exchange, distillation, or
reverse osmosis may be required as an initial treat- I
ment prior to distillation if the purity cannot be
attained by single distillation. (See Standard Specifi-
cation for Reagent Water, D1193-77 for more ;
information.)
7.4 Specify the concentration of inorganic reagents in
applicable terms, as follows: ;
Concentrated acids and bases density
Dilute acids and
bases. volume ratio, x + y (x volumes i
ofreagentaddedtoyvolumes |
of water)
Nonstandardized
solutions normality, expressed
decimally; or the equivalent of ;
1 mL of solution in terms of '
grams of a given element
expressed as 1 mL = x.xx
g of.... |
7.5 Reagents used for the same purpose in different i
methods should be of the same strength. Examples
of reagent descriptions and materials are as follows:
7.5.1 Ammonium Molybdate Solution (75 g/L) - :
Dissolve 7.5 g of ammonium molybdate
((NH4)6Mo7O24 4H20) in reagent water -
and dilute to 100 mL
7.5.2 Carbon Disulfide (CS2). (CASRN-75-1 5-0).
7.5.3 Chloroform (CHCI3). (CASRN-67-66-3).
7.5.4 Hydrochloric Acid (1+1) - Carefully add 1
volume of concentrated hydrochloric acid
(HCI, sp gr 1.19) to an equal volume of
reagent water.
7.5.5 Lead Solution, Stock (1.0 mL= 200 jug Pb)
Dissolve 0.3198 g of lead nitrate (Pb(N03)2)
in reagent water containing I mL of concentrated
HNO3 (sp gr 1.42) and dilute to I L with
reagent water.
7.5.6 Oxalic Acid Solution (100 g/L) -- Dissolve 10
g of oxalic acid (H2C2O4-2H2O) CASRN-6153-
56-6 in reagent water and dilute to 100 ML.
7.5.7 Pyrrolidine Dithiocarbamic Acid - Chloroform
Reagent- Add 36 mL of pyrrolidine (CASRN-
123-75-1) to 1 L of CHCI3. Cool the solution
and add 30 mL of CS2 in small portions,
swirling between additions. Dilute to 2 Lwith
CHCIa. The reagent can be used for several
months if stored in a cool, dark place.
CAUTION: All components of this reagent are
highly toxic. Carbon disulfide is also highly
flammable; prepare and use in a well-venti-
lated hood. Avoid inhalation and direct
contact.
7.6 Specify filter paper by describing the significant
characteristic such as porosity, rate of filtering, ash
content, etc., or by reference to ASTM Specification
D1100 for Filter Paper for Use in Chemical Analysis.
8- Sample Collection, Preservation and Storage
(Mandatory)
8.1 Give directions for collecting, preserving and storing
samples. Use preservation procedures and holding
times consistent with those specified in current EPA
publications or regulations and consistent with other
methods for the same analytes.
9- Calibration and Standardization (Mandatory)
9.1 Apparatus - Give such detailed instruction for calibra-
tion and adjustment of the apparatus as may be
necessary to use the method.
9.2 Give detailed instructions for the standardization of
reagents used in the method.
9.3 Calibration Curves and Tables - Give detailed instruc-
tions for the use of standards to prepare calibration
curves or tables. Include the number of calibration
standards, the need for blanks, the frequency of
calibration checks, the critical range, etc.
10. Quality Control (Mandatory)
10.1 Include here those procedures necessary to
acquire information to accurately define the quality
of data generated with the method.
10.1.1 Describe completely the procedure for
preparing spiking solutions (if not in the
Reagents Section) and the exact pro-
cedure for introducing spike. Identify the
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matrix if samples are not spiked. Provide
directions for calculating recoveries.
10.1.2 Describe completely the procedure for
preparing replicates, including the ap-
propriateness of field, laboratory, or partial
method replicates.
10.2 Include here any requirements for analysis of
quality control (QC) check samples using the
method.
10.3 Include here instructions for analyzing blanks
and standards using the complete analytical
procedure, the frequency of required analyses,
and interpretation of results.
10.4 Describe any special laboratory QC programs
required, such as participation in formal perfor-
mance evaluation (PE) studies.
1 1 . Procedure (Mandatory)
1 1.1 Include in proper sequence detailed directions
for performing the analysis. Describe the pro-
cedure in the imperative mood, present tense.
For example: "Heat the sample or sample
aliquot...," rather than "The sample or sample
aliquot should be heated.." Comments, descrip-
tive information, etc., not in the imperative mood,
may be included, if necessary. Write the text so
that it is concise and easily understandable. When
alternative procedures are given, state which is
preferred.
1 1 .2 In chemical methods, specify the size of sample
aliquot and indicate the required measurement
accuracy. (There is no need to weigh a sample to
five significant figures in a spectrophotometric
method where the final absorbance measurement
yields data with only three significant figures.)
11.3 If the method is straightforward or consists of a
single major step, place all operations under one
subsection. If the method is complex, however,
divide the determinative steps into several parts.
Also indicate when a determination may not be
interrupted overnight If timing is critical, it
should be so indicated. For a color reaction,
indicate how long the color is stable.
12. Calculations (Mandatory)
1 2. 1 Calculation ~ Give here, in the imperative mood,
directions for calculating the results of the analysis,
including any equations. Spell out names, e.g.,
Total Kjeidahl Nitrogen, in the text, but use the
abbreviation (TKN) in the equations to designate
individual values. Define the letter symbols im-
mediately under the equation. Use numerical
values for any constants. Dilution factors, titration
factors, etc., should be identified.
1 2.2 An example of a typical equation is:
/, M 1000(A-B) 14 N
mg/L TKN = - i-^-* -
B = mL of standard H2S04 used to titrate blank
N = normality of sulfuric acid titrant
14 = milliequivalent weight of nitrogen
S = mL of sample digested.
12.3 Reporting Results - Indicate the units in which
the results are to be reported, i.e., /JLQ/L, mg/kg,
etc. If the sample is a solid material such as a
sediment or sludge, indicate whether results are
to be reported as wet weight or dry weight basis.
Specify the number of significant figures to be
reported Report all values obtained by various
QC procedures (Sect 10) along with the cal-
culated results of the analysis.
12.4 Interpretation of Results - Use this heading in
place of "Calculations" when the results of the
analysis must be expressed in descriptive form,
relative terms, or abstract values. List and define
the descriptive terms or classifications used.
13. Precision and Accuracy (Mandatory)
13.1 As minimum, state single-operator precision and
accuracy on reagent water. If other sample types
have been investigated, also provide this informa-
tion for them. If a collaborative study has been
completed, describe it and report the number of
participating operators and laboratories, spike
concentrations, level of replication, types of back-
ground waters, and any other significant aspects.
13.2 Specify method precision as the overall and
single-operator standard deviations that can be
expected when the method is used by a com-
petent operator.
13.3 Specify method accuracy as the % recovery that
can be expected between analytical results and
the true value of the property being measured.
NOTE: Referto ASTM Standard Practice D2777
for details regarding the calculation re-
quired to properly respond to 13.2 and
13.3 above.
14. References
where:
A = mL of standard H2 SO4 used to titrate
sample
14.1 List references in the order cited in the method,
and assign each reference an arabic number.
14.2 References should not include documents that
are not readily accessible to the reader, such as
unpublished theses, personal communications,
private correspondence, etc.
14.3 Use the following format for order, content
and punctuation.
14.3.1 Books--author's nameor names (initials
last), title of book (underline, period, no
quotation marks), name of publisher,
address of publisher(city and state), year
of publication, and page number, if appli-
cable. Example:
Jones, J.J., Plasticity and Creep. John
Wiley & Sons,
1958, p. 250.
Inc., New York, N.Y.,
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14.3.2 Magazines and Journals author's name
or names (initials last), "title of paper"
(quotation marks, comma), volume
number, issue number (this may be
omitted if the journal page numbers are
continuous throughout the volume), date
of publication, and page numbers. Example:
Jones, J.J., and Smith, R.R.," Correlation
of Brinell Hardness and Tensile Strength,"
Materials in Design Engineering. Vol
10, No. 2, February 1958, pp. 52-67. A
list of common journal abbreviations is
given in Appendix C.
14.3.3 Proceedings, Transactions, Reports,
Bulletins, etc. authors name or names
(initials last), "title of paper" (in quotation
marks), name of publication (underline,
no quotation marks, comma), name of
publisher, volume number, if any date of
publication, and page numbera Examples:
Jones, J.J., "Lubrication Problems in
Space Vehicles," Transaction, Am. Soc.
Mechanical Engrs., Vol 52, 1948, pp.
135-140.
Jones, J.J., "Classification of Bitumens,"
Journal, Inst Petroleum, Vol 38, 1952,
p. 121.
Jones, J.J., "Fatigue of Aircraft Structures,"
NASA TR-108, Nat Aeronautics and
Space Administration, 1959.
Jones, J. J.," Effect of Carbon Content on
Notch Properties of Aircraft Steels,"
Bulletin 642, Engineering Experiment
Station, University of Illinois, 1957.
14.3.4 Symposium Volumes or Other Books
Comprising Collections of Papers- Follow
style for books, above and add title of
paper, in quotes, after author's name.
Patents -- patent number and data.
Example: U.S. Patent No. 2 232 185,
Feb. 18, 1941.
14.3.5 EPA methods - Method number and
name, EPA report number, U.S. Environ-
mental Protection Agency, laboratory and/
oroffice, location, date. Example: Method
503.1 - The Analysis of Aromatic
Chemicals in Water by the Purge and
Trap Method, EPA 600/4-81 -057, U.S.
Environmental Protection Agency, En-
vironmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268,
May 1980.
1 5.1.3 Detailed description of apparatus.
1 5.1.4 Directions for cleaning apparatus.
15.1.5 Notes on significance and interpretation
of the method, used to amplify the state-
ment in the text
15.1.6 Development of equations used in the
calculations.
15.1.7 Charts or supplementary information for
computations.
15.1.8 Suggested data forms for recording test
results.
15. Appendices (Optional)
15.1
Include additional useful information in one or
more appendices to the method. Examples of
such information may include:
1 5.1 .1 Glossary of terms used in the method.
15.1.2 List of symbols.
-------
Glossary
Item
Abbreviation
Definition
Field reagent FMB An aliquot of reagent water
blank or equivalent neutral refe-
rence material treated as a
sample in all aspects, includ-
ing exposure to a sample
bottle, holding time, preser-
vatives, and all preanalysis
treatments.
Laboratory LMB
reagent blank
Laboratory LCS
control stan-
dard
Laboratory LD
duplicate
A solution prepared as above
in the laboratory and treated
the same as a sample, except
that it is not taken to the
sampling site.
A solution prepared in the
laboratory by dissolving a
known amount of one or more
pure compounds in a known
amount of reagent water.
(This should not be confused
with a calibrating standard.)
Two aliquots of the same
environmental sample treated
identically throughout a la-
boratory analytical procedure.
Analysis of laboratory dupli-
cates indicates precision as-
sociated with laboratory pro-
cedures but not with sample
collection, preservation, or
storage procedures.
Acompound not expected to
be found in the sample, which
is added to the original en-
vironmental sample, and mea-
sured with the same pro-
cedures used to measure
sample components.
Field duplicate FD Two samples taken at the
same time and place under
identical circumstances which
are treated identically through-
out field and laboratory pro-
cedures. Analysis of field
duplicates indicates the pre-
cision associated with sample
collection, preservation, and
storage, as well as with la-
boratory procedures.
Surrogate SC
compound
Performance
evaluation
sample
Quality control
check sample
PES A sample containing known
concentrations (true values)
of method analytes distrib-
uted by the Quality Assur-
ance Branch (QAB), Environ-
mental Monitoring and Sup-
port Laboratory, USEPA Cin-
cinnati, Ohio 45268, to mul-
tiple laboratories for analyses
with procedures to be used
for environmental samples.
Results of analyses are used
by QAB to determine statis-
tically the accuracy and pre-
cision that can be expected
when a method is performed
by a competent analyst Ana-
lyte true values are unknown
to the analyst
QCS A sample containing known
concentrations (true values)
of analytes prepared by a
laboratory other than the la-
boratory performing the an-
alysis. The analyzing labora-
tory uses this sample to
demonstrate that it can obtain
acceptable identifications and
measurements with proce-
dures to be used to analyze
environmental samples. An-
alyte true values are usually
known by the analyst.
-------
-------
APPENDIX A
Method 524. Measurement of Purgeable Organic
Compounds in Drinking Water
by Gas Chromatography/Mass Spectrometry
February 1983
Ann Alford-Stevens
James W. Eichelberger
William L. Budde
Physical and Chemical Methods Branch
Environmental Monitoring and Support Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
11
-------
INDEX
Section
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
Subject :
Scope and Application
Summary of Method
Definitions i
Interferences
Safety
Apparatus and Equipment
Reagents and Consumable Materials
Sample Collection, Preservation and Handling
Calibration
Quality Control
Procedure :
Calculations
Precision and Accuracy
References !
1.
2.
3.
4.
5.
TABLES
Ion Abundance Criteria for p_-Bromofluorobenzene.
Single Laboratory Method Efficiency Data for Purgeable Organic Compounds
Measured with 6C/MS. i
Acceptable Storage Times for River and Drinking Water Samples Containing
Halogenated Aliphatic Analytes. j
Storage Time Data for River and Drinking Water Samples Containing
Aromatic Analytes. .
Single Laboratory Accuracy and Precision Data for Purgeable Organic
Compounds Measured with GC/MS.
12
-------
Method 524. Measurement of Purgeable Organic Compounds
in Drinking Water By Gas Chromatography/Mass Spectrometry
1. SCOPE AND APPLICATION
1.1 This is a general purpose method that provides procedures for
identification and measurement of purgeable organic compounds in
finished drinking water, raw source water, or drinking water in any
treatment stage. The method is applicable to a wide range of
organic compounds that have sufficiently high volatility and low
water solubility to be removed from water samples with purge and
trap procedures. Single-laboratory method efficiency, accuracy and
precision data have been determined for the following compounds:
Chemical Abstracts Service
Analyte
benzene
bis(2-chloroisopropyl) ether
bromochloromethane
bromodi chloromethane
4-bromof1uoro ben zene
bromoform
carbon tetrachloride
chlorobenzene
chlorod i bromometh ane
chloroform
chloromethane
1,2-di bromo-3-chloropropane
1,2-dichlorobenzene
1,3-dichlorobenzene
1,2-dichloroethane
1,1-dichloroethene
trans-1,2-dichloroethene
cis-1,3-di chloropropene
methylene chloride
styrene (ethenylbenzene)
1,1,2,2-tetrachloroethane
tetrachloroethene
toluene
1,1,1-tri chloroethane
1,1,2-tri chloroethane
trichloroethene
vinyl chloride
p-xylene
Registry Number ICASRNl
71-43-2
39638-32-9
74-97-5
75-27-4
460-00-4
75-25-2
56-23-5
108-90-7
124-48-1
67-66-3
74-87-3
96-12-8
95 -50-1
541-73-1
107-06-2
75-35-4
156-60-5
10061-01-5
75-09-2
100-42-5
79-34-5
127-18-4
108-88-3
71-55-6
79-00-5
79-01-6
75-01-4
106-42-3
STORET
Number
34030
34283
77297
32101
32104
32102
34301
32105
32106
34418
34536
34566
34531
34501
34546
34699
34423
77128
34516
34475
34010
34506
34511
39180
30175
A laboratory may use this method to detect and measure additional
analytes after the laboratory obtains acceptable (defined in
Section 10) accuracy and precision data for each added analyte.
13
-------
1.2 Detection Limits (MDLs) (1) are;compound dependent, varying with
purging efficiency and concentration, where MDL is defined as the
statistically calculated minimum amount that can be measured with
99% confidence that the reported! value is greater than zero. For
the listed analytes in reagent water, MDLs vary from 0.07 to 11.2
Vig/L. The applicable concentration range of this method is
Compound and instrument dependent but is approximately 0.2 yg to
200 yg of analyte per liter of undiluted sample. Analytes that are
inefficiently purged from' wateriwill not be detected when present
at low concentrations, but they'can be measured with acceptable
accuracy and precision when present in sufficient amounts.
1.3 Determination of some individual components of complex mixtures may
be -hampered by insufficient chrqmatographic resolution and/or by
large differences in concentrations of individual components.
2. SUMMARY OF METHOD \
Highly volatile organic compounds with low water solubility are removed
(purged) from the sample matrix by bubbling helium through a 25-mL
aqueous sample. Purged sample components are trapped in a stainless
steel tube containing suitable sorbent materials. When purging is
complete, the sorbent tube is heated 'and backflushed with helium to
desorb purged sample components into >a gas chromatograph (GC) interfaced
to a mass spectrometer (MS). Compounds eluting from the GC column are
tentatively identified by comparing iJheir mass spectra to reference
spectra in a data base. Tentative identifications are confirmed by
analyzing standards under the same conditions used for samples and
comparing resultant mass spectra and [GC retention times. Each identi-
fied component is measured by relating the MS response for an appro-
priate selected ion produced by that compound to the MS response for the
same ion from that same compound in a[n external standard or for another
ion produced by a compound that is used as an internal standard.
3. DEFINITIONS \
External standard a known amount of a pure compound that is analyzed
with the same procedures and conditions that are used to analyze samples
containing that compound. From measujred detector responses to known
amounts of the external standard, a concentration of that same compound
can be calculated from measured detector response to that compound in a
sample analyzed with the same procedures.
Internal standard ~ a pure compound !added to a sample in known amounts
and used to calibrate concentration measurements of other compounds that
are sample components. The internal standard must be a compound that is
not a sample component.
i
Field duplicates two samples taken; at the same time and place under
identical circumstances and treated exactly the same throughout field
and laboratory procedures. Analysis of field duplicates indicates the
precision associated with sample collection, preservation and storage,
as well as with laboratory procedures i.
14
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Field reagent blank reagent water placed in a sample container in the
laboratory and treated as a sample in all respects, including exposure
to sampling site conditions, storage, preservation and all analytical
procedures.
Laboratory control standard a solution of analytes prepared in the
laboratory by dissolving known amounts of pure compounds in a known
amount of reagent water. In this method, the laboratory control
standard is prepared by adding appropriate volumes of the secondary
dilution standard solution and the internal standard/surrogate compound
spiking solution to reagent water.
Laboratory duplicates two aliquots of the same sample that are
treated exactly the same throughout laboratory analytical procedures.
Analysis of laboratory duplicates indicates precision associated with
laboratory procedures but not with sample collection, preservation or
storage procedures.
Laboratory reagent blank a 25-mL portion of reagent water placed in
the purging apparatus and analyzed as if it were a sample.
Performance evaluation sample a methanol solution of method analytes
distributed by the Quality Assurance Branch (QAB), Environmental
Monitoring and Support Laboratory, USEPA, Cincinnati, Ohio, to multiple
laboratories for analysis. A small volume of the methanol solution is
added to a known volume of reagent water and analyzed with procedures
used for samples. Results of analyses are .used by the QAB to determine
statistically the accuracy and precision that.can be expected when a
method is performed by competent analysts. Analyte true values are
unknown to the analyst.
Quality control check sample a methanol solution containing known
concentrations of analytes prepared by a laboratory other than the
laboratory performing the analysis. The analyzing laboratory uses this
solution to demonstrate that it can obtain acceptable identifications
and measurements with a method. A small volume of the methanol solution
is added to a known volume of reagent water and analyzed with procedures
used for samples. True values of analytes are known by the analyst.
Secondary dilution standard a methanol solution of analytes prepared
in the laboratory from stock standard solutions and diluted as needed to
prepare aqueous calibration solutions and laboratory control standards.
Stock standard solution a concentrated solution containing a
certified standard that is a method analyte, or a concentrated methanol
solution of an analyte prepared in the laboratory with an assayed
reference compound. Stock standard solutions are used to prepare
secondary standard solutions.
Surrogate compound a compound that is not expected to be found in the
sample, is added to the original environmental sample to monitor perform-
ance, and is measured with the same procedures used to measure sample
components.
15
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4. INTERFERENCES
4.1 Samples may be contaminated diming shipment or storage by diffusion
of volatile organics through the sample bottle septum seal. Field
reagent blanks must be analyzed to determine when sampling and
storage procedures have not prevented contamination.
4.2 During analysis, major contaminant sources are volatile materials
in the laboratory and impurities in the inert purging gas and in
the sorbent trap. Analyses of field reagent blanks and laboratory
reagent blanks provide information about the presence of contami-
nants, i
4.3 Interfering contamination may olccur when a sample containing low
concentrations of volatile orgainic compounds is analyzed
immediately after a sample containing relatively high concentra-
tions of volatile organic compo'unds. A preventive technique is
between-sample rinsing of the purging apparatus and sample syringes
with two portions of reagent water. After analysis of a sample
containing high concentrations lof volatile organic compounds, the
system should be baked for 10 njin by passing helium through the
sample purging chamber into the| heated (180°) sorbent trap. One
or more laboratory reagent blanks should be analyzed to ensure that
accurate values are obtained fof the next sample.
5. SAFETY :
i
5.1 The toxicity or carcinogenicity, of chemicals used in this method
has not been precisely defined;| each chemical should be treated as
a potential health hazard, and exposure to these chemicals should
be minimized. Each laboratory !is responsible for maintaining
awareness of OSHA regulations regarding safe handling of chemicals
used in this method. Additional references to laboratory safety
are cited (2-4). :
5.2 The following method analytes have been tentatively classified as
known or suspected human or mammalian carcinogens: benzene, carbon
tetrachloride, chloroform, and [vinyl chloride. Pure, standard
materials and stock standard solutions of these compounds should be
handled in a hood.
i
6. APPARATUS AND EQUIPMENT i
i
6.1 Sample containers 120-ml or [larger glass bottles each equipped
with a screw cap and a polytetrafluoroethylene-faced silicone
septum. I
6.2 Purge and trap device consisting of sample purging chamber, sorbent
trap and desorber. (Acceptable devices are commercially available.)
i
6.2.1 The all glass sample purging chamber holds 25-mL samples
with < 15 ml of gaseous headspace between the water column
and the trap. The helium purge gas passes through the water
column as finely divided: bubbles (optimum diameter of <3 mm
16
-------
at the origin). The purge gas must be introduced at a
point <5 mm from the base of the water column.
6.2.2 The stainless steel sorbent trap is 25 cm long by 2.5 mm ID
and is packed with 8 cm of Tenax-GCR, 8 cm of silica gel,
and 8 cm of charcoal, in that order with respect to the
inlet end of the trap. The charcoal is not necessary for
listed analytes but is necessary if fluorine-substituted
methanes and ethanes (fluorocarbons) are among additional
analytes. When analytes do not include fluorocarbons, the
charcoal may be eliminated, and the amount of Tenax-GCR
may be increased. A trap with different dimensions can be
used if it has been evaluated and found to perform satisfac-
torily (i.e., provides method efficiencies equal to or
better than those in Table 2). Before initial use, the trap
should be conditioned overnight at 180°C by backflushing
with helium flow of at least 20 mL/min. Each day the trap
should be conditioned for 10 min at 180°C with back-
flushing.
6.2.3 The desorber should be capable of rapidly heating the trap
to 180°C. The trap section containing Tenax-GCR should
not be heated to higher than 180°C, and the temperature of
the other sections should not exceed 200°C.
6.3 SYRINGES AND SYRINGE VALVES
6.3.1 Two 25-ml glass hypodermic syringes with Luer-LokR tip (if
applicable to the purging device being used).
6.3.2 One 5-mL gas-tight syringe with shutoff valve.
6.3.3 Two two-way syringe valves with Luer ends (if applicable to
the purging device being used).
6.3.4 Micro syringes, various sizes.
6.4 MISCELLANEOUS
6.4.1 Standard solution storage containers -- 10-mL bottles with
polytetrafluoroethylene-lined screw caps.
6.4.2 Analytical balance capable of weighing 0.0001 g accurately.
6.4.3 Helium purge gas, as contaminant free as possible.
6.5 GAS CHROMATOGRAPH/MASS SPECTROMETER/DATA SYSTEM (GC/MS/DS)
6.5.1 The GC must be capable of temperature programming. Any
column (either packed or capillary) that provides data with
adequate accuracy and precision (Sect. 10) can be used. If
a packed column is used, the GC usually is interfaced to the
MS with an all-glass enrichment device and an all-glass
17
-------
transfer line, but any enrichment device or transfer line
can be used if performance specifications described in this
method can be demonstrated with it. If a capillary column
is used, an enrichment device is not needed. A recommended
packed GC column for the listed analytes is 1.8m long by 2
mm ID glass packed with 1% SP-1000 on 60/80 mesh Carbopack
B. Recommended operating parameters for that column are:
helium carrier gas flojw rate of 30 nt/min and temperature of
45°c for 4 min, increased to 230°C at a rate of
80c/min, and isothermal at 230°C for at least 25 min or
until all expected analytes elute. An alternative recom-
mended packed column is 1.8 m long by 2 mm ID glass or
stainless steel packed^ with 0.2% Carbowax 1500 on 80/100
mesh Carbopack C. :
6.S..2 Mass spectral data are1 obtained with electron-impact
ionization at a nominal electron energy of 70 eV. The mass
spectrometer must be capable of scanning from 35 to 450 amu
every 7 s or less and must produce a mass spectrum that
meets all criteria in Table 1 when 50 ng or less of
£-bromof1uorobenzene (BFB) is introduced into the GC. To
ensure sufficient precision of mass spectral data, the
desirable MS scan rate allows acquisition of at least five
spectra while a sample; component elutes from the GC. With
capillary columns which produce narrower peaks than packed
columns that criterion'may not be feasible and adequate
precision with fewer spectra per GC peak must be
demonstrated (Sect. 10).
6.5.3 An interfaced data sysjtem (DS) is required to acquire,
store, reduce and output mass spectral data. The computer
software must allow searching any GC/MS data file for ions
of a specific mass and! plotting ion abundances versus time
or scan number. This type of plot is defined as an
extracted ion current profile (EICP). Software must also
allow integrating the Abundance in any EICP between speci-
fied time or scan number limits.
7. REAGENTS AND CONSUMABLE MATERIALS :
'"' -'-'L- - - ~~ - -- --- .I.-. !
7.1 SORBENT TRAP PACKING MATERIALS
7.1.1 Polymer based on 2,6-diphenyl-£-phenylene oxide -- 60/80
mesh Tenax-GCR, chromatographic grade, or equivalent.
\
7.1.2 Coconut charcoal -- 26 mesh.
i.
7.1.3 Silica gel 35/60 mesh, Davison Chemical grade 15, or
equivalent. \
7.2 REAGENTS :
7.2.1 Methanol ~ pesticide quality or equivalent.
18
-------
7.3
7.2.2 Reagent water water in which an interferent is not
observed at the method detection limit of the compound of
interest. Prepare reagent water by passing tap water through
a filter bed containing about 0.5 kg of activated carbon, by
using a water purification system, or by boiling distilled
water for 15 min followed by a 1 h purge with inert gas
while the water temperature is held at 90°C. Store in
clean, narrow-mouth bottles with polytetrafluoroethylene-
lined septa and screw caps.
7.2.3 Sodium thiosuIf ate or
reagent grade.
sodium sulfite -- granular, ACS
STOCK STANDARD SOLUTIONS -- These solutions may be purchased as
certified solutions or prepared from pure standard materials using
the following procedures:
7.3.1 Place about 9.8 ml of methanol in a 10-mL ground-glass
stoppered volumetric flask. Allow the flask to stand
unstoppered for about 10 min or until all alcohol-wetted
surfaces have dried. Weigh the flask to the nearest 0.1
mg.
7.3.2 If the analyte is a liquid at room temperature, with a
100-uL syringe immediately add two or more drops of assayed
reference compound to the flask. (The liquid must fall
directly into the alcohol without contacting the flask). If
the analyte is a gas at room temperature, fill a 5-mL valved
gas-tight syringe with the standard to the 5.0-mL mark,
lower the needle to 5 mm above the methanol meniscus, and
slowly inject the standard into the neck of the flask. (The
gas will rapidly dissolve in the methanol.)
7.3.3 Reweigh the flask, dilute to volume, stopper, and mix by
inverting several times.
7.3.4 From the net weight gain, calculate the concentration in
micrograms per micro!Her. When assayed compound purity is
>96%, the uncorrected weight may
concentration.
be used to calculate
7.3.5 Store stock standard solutions with minimal headspace in
polytetrafluoroethylene-lined screw-capped bottles.
Methanol solutions of listed liquid analytes are stable for
at least four weeks when stored at 4°C. Methanol
solutions prepared from listed gaseous analytes are not
stable for more than one week when stored at <0°C; at room
temperature, they must be discarded after one day.
7.4 SECONDARY DILUTION STANDARD Use stock standard solutions to
prepare a secondary dilution standard solution that contains the
analytes in methanol. The secondary dilution standard should be
prepared at a concentration that can be easily diluted to prepare
19
-------
aqueous calibration solutions (Section 9.2.1.2) at concentrations
that will bracket the working concentration range. Store the
secondary dilution standard solution with minimal headspace and
check frequently for signs of deterioration or evaporation,
especially just before preparing calibration solutions from it,,
7.5 INTERNAL STANDARD SPIKING SOLUTION AND SURROGATE COMPOUND SPIKING
SOLUTION Prepare a solution of fluorobenzene in methanol at a
concentration that allows use of 2 to 10 uL to add an appropriate
amount of fluorobenzene to each sample; this amount should be
approximately the same as the amount of the analyte to be measured.
If the internal standard technique is used, fluorobenzene serves as
the internal standard. If the external standard technique is used,
fluorobenzene is a surrogate1compound added to each sample to
monitor method performance. Fluorobenzene was selected because it
is stable in aqueous solutions, is efficiently purged, does not
occur naturally, and is not tommercially produced in bulk
quantities but is available as a laboratory reagent chemical.
8. SAMPLE COLLECTION, PRESERVATION AND HANDLING
8.1 Collect all samples in duplicate. Fill sample bottles to over--
flowing. No air bubbles should pass through the sample as the
bottle is filled, or be trapped in the sample when the bottle is
sealed. Keep samples sealed1 from collection time until analysis.
Maximum storage times vary with analytes of concern. Recent
studies (5-6) provided data ^'ndicating appropriate storage times
for samples (river and drinking water) containing compounds that
are potential method analytes (Tables 3 and 4).
8.1.1 When sampling from a water tap, open the tap and allow the
system to flush until! the water temperature has stabilized
(usually about 10 min). Adjust the flow to about 500 mL/min
and collect duplicate; samples from the flowing stream.
8.1.2 When sampling from an open body of water, fill a 1-qt
wide-mouth bottle with sample from a representative area,
and carefully fill duplicate sample bottles from the 1-qt
bottle. ;
8.2 SAMPLE PRESERVATION
8.2.1 If styrene (which reacts with chlorine) and/or trihalo-
methanes are to be measured in a sample expected to contain
residual chlorine, add a reducing agent, sodium thiosulfate
or sodium sulfite (30:mg per 120-mL sample for up to 5 ppm
chlorine) to the empty sample bottle before it is shipped to
the sampling site.
NOTE: Some possible analytes may be unstable in the
presence of reducing agent. Data (5) indicate that sodium
sulfite should not beiused if analytes include
chloromethane, 1,1-dichloroethene, 1,1-dichloropropene,
20
-------
2-chloroethyl ethyl ether, or 1,1,2,2-tetrachloroethane;
sodium thiosulfate is not recommended if analytes include
chloromethane or 1,2-dibromoethane.
8.2.2 Much remains to be learned about biological degradation of
aromatic hydrocarbon analytes. Currently, two preservation
techniques are recommended but both.have negative aspects.
8.2.2.1 Hydrochloric acid may be used at the sampling site
to adjust the sample pH to < 2; the major disadvan-
tages of this procedure are that shipping acid is
restricted by federal regulations and that effects
of low pH on other analytes (such as organohalides)
are largely unknown.
8.2.2.2 Mercuric chloride may be added to the sample bottle
in amounts to produce a concentration of 10 mg/L.
This may be added to the sample at the sampling site
or to the sample bottle in the laboratory before
shipping to the sampling site. A major disadvantage
of mercuric chloride is that it is a highly toxic
chemical; it must be handled with caution, and
samples containing it must be disposed with appro-
pri ate procedures.
8.2.2.3 If analytes include both aromatic hydrocarbons and
styrene or trihalomethanes, current recommendations
are either to add both preservative types (reducing
agent along with acid or mercuric chloride) or to
collect two samples with the appropriate preserva-
tive type in each.
8.2.3 After addition of preservati ve(s), seal the sample bottle
and shake vigorously for 1 min.
8.3 FIELD BLANKS
8.3.1 Duplicate field reagent blanks must be handled along with
each sample set, which is composed of the samples collected
from the same general sample site at approximately the same
time. At the laboratory, fill field blank sample bottles
with reagent water, seal, and ship to the sampling site
along with empty sample bottles and back to the laboratory
with filled sample bottles. Wherever a set of samples is
shipped and stored, it is accompanied by appropriate blanks.
8.3.2 When reducing agent or preservative(s) is added to samples,
use the same procedures used for samples to add the same
amount to blanks. The reducing agent
1abor atory.
can be added in the
21
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9. CALIBRATION
9.1 INITIAL CALIBRATION
9.1.1 CALIBRATION SOLUTIONS
9,1.1.1 At least three calibration solutions, each contain-
ing a standard of each analyte, are needed. (More
than three calibration solutions may be required if
analytes are numerous.) One calibration.solution
should contain each analyte at a concentration
approaching but [greater than the method detection
limit (Table 5) !for that compound; the other two
solutions should contain analytes at concentrations
that bracket the range expected in samples. For
example, if the detection limit for a particular
analyte is 0.2 iig/L, and a 25-nt sample expected to
contain approximately 5 yg/L is analyzed, aqueous
solutions of standards should be prepared at
concentrations of 0.3 yg/L, 5 yq/L, and 10 "q' .
9.1.1.2 To prepare calibration solutions, add appropriate
volumes (yL) of ;the secondary dilution standard
solution to aliquots of reagent water. Remove the
plunger from a 2;5-rrt syringe and attach a closed
syringe valve. 'Fill the syringe with reagent water,
replace the plunger, and compress the water. Open
the syringe valve and vent air. Adjust the reagent
water volume to 125 mL and add a carefully measured
aliquot of 2.0 tla 18.0 yL of the secondary dilution
standard through! the valve bore. Add the appro-
priate amount (>i 2.0 yL) of the internal standard
surrogate spiking solution through the valve bore,
but do not add more than 20 yL total volume of
methanol solution.
NOTE: If appropriate concentrations cannot be
prepared without! adding more than 20 yL of the
secondary dilution standard to 25 mL of reagent "
water, prepare aj new secondary dilution standard.
If less than 2,0
-------
1 h. Other aqueous solutions can be stored for up
to 24 h.
9.1.2 Analyze triplicate aliquots of each calibration solution
with the procedures to be used to analyze samples.
9.1,2.1 If the external standard technique is being used,
prepare a concentration calibration curve for each
analyte by plotting integrated abundances of the ion
characteristic of that compound as a function of the
concentration. If the ratio of ion abundance to
amount of analyte is constant (< 10% relative
standard deviation) throughout the concentration
range, the average ratio may be used instead of a
calibration curve.
9.1.2.2 If the internal standard technique is being used,
calculate the mass spectrometer response to each
compound relative to fluorobenzene, the internal
standard. Calculate the response factor (RF) with
the equation,
RF = V Qs ,
where Ax =
Qs
Qx
V
integrated abundance of the selected ion for
the analyte standard;
integrated abundance of the selected ion for
the internal standard;
quantity of internal standard; and
quantity of analyte standard.
RF is a unit!ess number; units used to express quantities of
analyte and internal standard must be equivalent. Ideally,
the response factor for each analyte should be independent
of analyte quantity for the working range of the
calibration, but required linearity will vary with required
accuracy of analyte concentration measurements. Generally,
acceptable variations of mean RF values are ± 15% over a
concentration range of two orders of magnitude and ± 10% RSD
of values obtained from analyses of triplicate aliquots of
each concentration calibration solution. For an analyte
with non-linear RF, a calibration curve of Areax/Areas
plotted versus Qx may be used to determine an analyte
concentration.
9.2 DAILY CALIBRATION Check calibration data each day by measurement
of one or more laboratory control standards or calibration solu-
tions. If the expected ion abundance was observed (Sect. 10.5) for
50 ng of the MS performance standard but the absolute ion abundance
23
-------
measured for any analyte varies from expected abundance by more
than 15%, prepare and analyze a fresh calibration solution to
determine if the problem islbeing caused by deterioration of the
calibration solution or by a malfunction in the purge and trap
internal standard technique is being used,
response factors have not changed. When
relative standard deviation), prepare and
solutions to determine new response factors.
apparatus. When the
verify each day that
changes occur (> 10%
analyze new standard
NOTE: Some analysts have observed marked deterioration of MS
response after the initial purge and trap analysis each day; if
this phenomenon is observed.j perform one purge/desorb cycle before
checking MS performance and [calibration data.
10. QUALITY CONTROL
_i_______
10.1 Minimum quality control requirements consist of:
10.1.1 initial demonstration of laboratory analytical capability
(efficiency, accuracy, and precision procedures, Sect. 10),
10.1.2 analysis of an MS performance standard and a laboratory
control standard near the beginning of each 8-h work period,
i
10.1.3 analysis of a field reagent blank along with each sample set,
i
10.1.4 analysis of a laboratory reagent blank when the field
reagent blank contains analytes at concentrations above the
method detection limits,
10.1.5 quarterly analysis of a quality control check sample, (if
available for analytes of concern), and
10.1.6 continued maintenance of performance records to define the
quality of generated data.
i
10.2 METHOD EFFICIENCY For each analyte, calculate method efficiency
by comparing the detector response when the compound is introduced
by syringe injection with the detector response when the same
amount is introduced by purging, trapping, and desorption. Because
of the calibration technique used in this method, high efficiency
is not required for acceptable precision and accuracy, but low
method efficiency may cause iunacceptably high detection limits.
Measure method efficiency fpr each analyte whenever the analytical
system undergoes major modification, such as replacement of trap
packing.
10.2.1 Analyze at least five laboratory control standards with the
purge, trap, desorption and 6C/MS detection procedures.
Interspersed among these five or more analyses, inject two
or more aliquots of the secondary dilution standard solution
24
-------
(Section 7.4) directly into the GC to introduce each analyte
in an amount equal to that introduced by purge and trap
procedures. Use the same MS data acquisition parameters for
injected analytes as those used for purge and trap proce-
dures .
10.2.2 Calculate the method efficiency (E) for each analyte in each
aliquot of the laboratory control standard with the equation:
E =
100
Ai
where Ap =
AT =
ion abundance of compound introduced with purge
and trap techniques, and
ion abundance produced by an equal amount of
the same compound when injected.
For this calculation, use data obtained from an injection
either closely preceding or following the purge and trap
analysis from which data are used.
10.2.3 Calculate the mean method efficiency for each analyte.
Acceptable detection limits usually can be achieved even if
the mean method efficiency is only 20 to 30%.
10.3 ACCURACY To determine accuracy, analyze duplicate aliquots of .a
quality control (QC) check sample containing known amounts of
analytes of concern. QC check samples for some, but not all listed
analytes, currently are available from the U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Quality Assurance Branch, Cincinnati, Ohio 45268; alternatively
certified standard solutions may be purchased from commercial
vendors.
10.3.1 When using the external standard procedure, calculate
accuracy as the ion abundance found in the QC sample
solution expressed as a percentage (P) of the ion abundance
found in the external standard solution:
A..
P =
A
. 100
where Ax = abundance of ion used to measure an analyte in
an aliquot of the QC check sample, and
As = abundance of ion used to measure an equal
amount of the same analyte treated as an
external standard.
10.3.2 When using the internal standard procedure, fluorobenzene in
the solution of analyte standards is the internal standard.
25
-------
Calculate response factors (Sect. 9.3.4) for each analyte
relative to fluorobenzqne. With these response factors,
calculate accuracy with data acquired for the QC check
sample: ;
P =
A
100
A.
RF
where Ax = abundance ofi ion used to measure an analyte in
an aliquot of the QC check sample,
As = abundance of ion used to measure
fluorobenzene in the same aliquot, and
RF = response factor of the particular
analyte relative to fluorobenzene.
NOTE: The internal 'standard concentration is constant in
calibration solutions and all samples for which the
calibration solution's are used (Section 9.3).
10.3.3 For each analyte, the mean accuracy should be in the range
of 85 to 115%. For sonje listed analytes, this may not be
feasible for low concentration measurements.
10.4 PRECISION
10.4.1 For each analyte, calcul
devi ation (s, in ug/L)
obtained in the accuracy
s =
ate method precision as the standard
of the replicate measured values
calculations:
n
n
n 1-1
i=1Xi
n (n-1)
where n = number of measurements for each analyte, and
X = individual measured value.
10.4.2 For the set of measured values for each analyte, calculate
the dispersion as the percent relative standard deviation
(RSD):
RSD =
100
where s = standard deviation, and
C = mean observed, concentration.
i
10.4.3 Adequate precision is obtained when the relative standard
deviation is <_20%. Fdr some listed analytes, this may not
be feasible for low concentration measurements.
26
-------
10.5 MS PERFORMANCE STANDARD
10.5.1 Near the beginning of each 8-h work period in which analytes
are to be measured, measure the mass spectrum produced by 50
ng of £-bromofluorobenzene (BFB) to ensure that it meets
performance criteria (Table 1). BFB may be introduced into
the MS either by syringe injection or through the purge and
trap system. It may be a component of the laboratory
control standard analyzed daily to check calibration (Sect.
7). Measure the entire mass spectrum at an MS scan rate
that produces at least five spectra for the BFB GC peak but
does not exceed 7 s per spectrum. Although acquisition of
five spectra per BfB GC peak may not be feasible when capil-
lary columns are used, BFB performance criteria still must
be met. If the BFB spectrum is unacceptable, adjust GC/MS
operating parameters until an acceptable spectrum is pro-
duced before samples are analyzed.
10.5.2 Record the absolute ion abundance detected for 50 ng of
BFB. If ion abundance varies more than ± 10% from the
expected number, check the GC/MS system to locate and
correct the problem. Preparation of a new calibration curve
may be necessary if the system is operating acceptably but
with decreased sensitivity.
10.6 LABORATORY CONTROL STANDARD To demonstrate that the calibration
curve is still valid, analyze a laboratory control standard at the
beginning of each 8-h work period.
10.6.1 For each analyte to be measured, select a concentration
representative of its occurrence in drinking water samples.
10.6.2 Prepare the laboratory control standard with either of the
following procedures:
10.6.2.1 From stock standard solutions, prepare a
laboratory control standard concentrate in
methanol. This solution should contain analytes
at concentrations 2500 times those selected as
representative concentrations. Add 10 yL of the
laboratory control standard concentrate to a 25-mL
aliquot of reagent water.
10.6.2.2 Add 2 to 18 uL of the secondary dilution standard
to 25 mL of reagent water contained in the sample
syringe.
10.6.3 Add an appropriate volume of the internal standard/surrogate
spiking solution and analyze with the same procedures (Sect.
11) to be used for samples.
27
-------
10.6.4 Determine calibration ^acceptability and appropriate remedial
actions, if needed. (For the external standard technique,
see Sect. 9.1.2.1; for the internal standard technique, see
Sect. 9.1.2.2.)
10.7 MONITORING THE SLRROGATE COMPOUND/INTERNAL STANDARD Because all
samples and laboratory control standards contain equal amounts of
the internal standard/surrogate compound, use the absolute ion
abundance for the .characteristic ion of that compound, fluoro-
benzene, to monitor system performance. If for any sample, the
absolute ion abundance varies; more than 15% from that observed in
the previous sample or laboratory control standard, do not report
analyte values obtained for that sample, and take remedial actions
to solve the system performance problem.
10.8 FIELD REAGENT BLANKS Analyze a field reagent blank along with
each sample set. If a field reagent blank contains analytes at
concentrations above the methpd detection limits, analyze a
laboratory reagent blank. If one or more analytes that are not
detected at concentrations above method detection limits in the
laboratory reagent blank are [detected in significant amounts in the
field blank, sampling or storjage procedures have not prevented
sample contamination, and the appropriate analyte measurement(s)
must be discarded.
10.9 At least quarterly, analyze a| quality control check sample obtained
from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory, Quality Assurance Branch,
Cincinnati, Ohio. Quality control check samples currently are
available for some but not all listed analytes. If measured
analyte concentrations are nojt within ±20% of true values, check
the entire analytical procedure to locate and correct the problem
source. I
10.10 Additional QC procedures may be necessary, depending on the purpose
of the analysis performed with this method.
10.10.1 Laboratory Duplicates To determine precision
associated with laboratory techniques, analyze two
aliquots (Sect, ll.il .2) of a sample in which some
analytes were detected in measurable quantities.
Calculate the rangej (R) of concentrations measured for
each duplicate pair:
R = Ci - C2» !
where C] represents the larger and,
C2 represent|s the smaller of the two
measurements,.
Calculate percent relative range
analyses using the formula:
(RR) of duplicate
28
-------
RR =
TOO
10.10.2
10.10.3
where R = range of concentrations, measured, and
C = mean concentration measured.
Generally, if RR is greater than 30%, precision is..
inadequate, and laboratory techniques must be improved.
Field Duplicates * Analyze 10% of samples in which some
analytes were detected in measurable quantities to
indicate precision limitations imposed by sampling,
transport and storage techniques as well as laboratory
techniques. If acceptable results are obtained from
analysis of field duplicates, analysis of laboratory
duplicates is usually not necessary.
Matrix Effects Determination To indicate matrix
effects on method efficiency, accuracy and precision when
raw source waters or drinking water during treatment is
to be analyzed, analyze aliquots to which known amounts
of analytes have been added. Because analytes may be
present in the unspiked aliquots, analysis of one or more
unspiked aliquots is necessary to determine initial
concentrations, which are then subtracted from concentra-
tions measured in spiked aliquots. For each analyte .the
amount added to determine matrix effects should exceed
twice the amount measured in unspiked aliquots.
11. PROCEDURE
11.1 ANALYSIS PROCEDURES
11.1.1
Initial
to 40 ±
devi ce,
syringe
conditions Adjust the helium purge gas flow rate
3 mL/min. Attach the sorbent trap to the purging
and set the device to the purge mode. Open the
valve located on the sample introduction needle of
the purging chamber.
11.1.2 Sample introduction and purging Remove the plunger from a
25-mL syringe and attach a closed syringe valve. Open the
sample or standard bottle, which has been allowed to come to
ambient temperature, and pour the sample into the syringe
barrel to just short of overflowing. Replace the syringe
plunger and compress the sample. Open the syringe valve and
vent any residual air while adjusting the sample volume to
25.0 ml. (Because this process of taking an aliquot impairs
the integrity of the remaining sample, a second syringe
should be filled at the same time, in case a second analysis
is required.) Add 2 to 20 uL of the spiking solution (Sect.
7.5) of fluorobenzene in methanol through the syringe valve
and close the valve. Attach the syringe and its valve
29
-------
assembly to the syringe valve on the purging device. Open
the syringe valves and slowly inject the sample into the
purging chamber. Close both valves and purge the sample for
11.0 ± 0.1 min at ambient temperature. Because temperature
affects purging efficiencies of some analytes, purging
chamber temperature must be controlled to maintain constant
(approximately ± 2°C)|temperature throughout calibration
and sample analyses. , If laboratory temperature is not
controlled adequately|, the purging chamber can be placed in
a thermostatically controlled water bath.
11.1.3 Desorption and data acquisition -- At the conclusion of
purging, adjust the purge and trap apparatus to the desorb
mode, and initiate GCj temperature programming, trap heating,
and MS data acquisition. Desorb for 4 min,, Transfer
trapped sample components into the GC column by heating the
trap to 180°C rapidlyjwhile it is backflushed with helium
flowing at 20 to 60 nt/min. (If the trap cannot be heated
rapidly, use the GC cdlumn as a secondary trap by cooling
the column to < 30°C (taring desorption.)
11.1.4 Sample chamber rinsing During or after desorption empty
the purging chamber w]th the sample introduction syringe,
and rinse the chamber;with two 25-mL portions of reagent
water. j
11.1.5 Trap reconditioning j- After desorbing the sample for 4 min,
reset the purging device to the purge mode. After 15 s,
close the syringe vaHe on the purging device to begin gas
flow through the trap^ After approximately 7 min, turn off
the trap heater and open the syringe valve to stop gas flow
through the trap. When cool (<25°C), the trap is ready
for the next sample.
11.1.6 Termination of data acquisition When sample components
have eluted from the GC, terminate MS data acquisition and
store data files on the data system storage device. Use
appropriate data output software to display full range mass
spectra and appropriate extracted ion current profiles
(EICPs). If any ion abundance exceeds the system working
range, dilute the sample aliquot in the second syringe with
reagent water and analyze the diluted aliquot.
11.2 IDENTIFICATION PROCEDURES CRITERIA Tentatively identify a sample
component by comparison of its mass spectrum (after background
subtraction) to a reference spectrum in a collection. Use the
following criteria to confirm a tentative identification:
11.2.1 The GC retention time'of the sample component must be within
J; s of the time observed for that same compound when a
calibration solution was analyzed. Calculate the value of Jt
with the equation: :
30
-------
t - (RT)V3
where RT = observed retention time (in seconds) of the
compound when a calibration solution was analyzed.
11.2.2 All ions that are present above 10% relative abundance in
the mass spectrum of the standard must be present in the
mass spectrum of the sample component and should agree
within absolute 10%. For example, if an ion has a relative
abundance of 30% in the standard spectrum, its abundance in
the sample spectrum should be in the range of 20 to 40%.
11.2.3 Identification is hampered when sample components are not
resolved chromatographically and produce mass spectra
containing ions contributed by more than one analyte.
Because purgeable organic compounds are relatively small
molecules and produce comparatively simple mass spectra,
this is not a significant problem for most method analytes.
When GC peaks obviously represent more than one sample
component (i.e., broadened peak with shoulder(s) or valley
between two or more maxima), appropriate analyte spectra and
background spectra can be selected by examining EICPs of
characteristic ions for tentatively identified components.
When analytes coelute (i.e., only one GC peak is apparent),
the identification criteria described in Section 11.2.2 can
be met but each analyte spectrum will contain extraneous
ions contributed by the coeluting.compound.
11.2.4 Structural isomers that produce very similar mass spectra
can be explicitly identified only if they have sufficiently
different GC retention times. Acceptable resolution is
achieved if the height of the valley between two isomer
peaks is less than 25% of the sum of the two peak heights.
Otherwise, structural isomers are identified as isomeric
pairs.
12. CALCULATIONS
12.1 Complete chromatographic resolution is not necessary for accurate
and precise measurements of analyte concentrations, if unique ions
with adequate intensities are selected for EICPs. For example,
although two listed analytes, 1,1,2,2-tetrachloroethane and
tetrachloroethene, were not resolved with the GC conditions used
and produced mass spectra containing common ions, concentrations
(Table 5) were calculated by measuring appropriate characteristic
ions.
12.1.1 With either the internal or external standard technique,
calculate analyte concentrations with the equation:
A_
RF
31
-------
where Cx
AX
AS -
RF
Qs =
V
analyte concentration in micrograms per liter;
integrated ion abundance of a significant
characterjistic ion of the sample analyte;
integrated ion abundance of a significant
characteristic ion of the standard (either
internal jor external), in units consistent with
those used for the analyte ion abundance;
response If actor (With an external standard,
RF = 1, tjecause the standard is the same
compound ;as the measured analyte.);
quantity |of internal standard added or quantity
of external standard that produced As, in
micro grams; and
= purged sample volume in liters.
12.1.2 With the external standard technique, As is a point on
concentration calibration curve and is the same number
the
as
Ax; Qs is the
obtained from
quantity that produces As and also is
the concentration calibration curve.
12.1
.3 For each analyte, select a significant characteristic ion.
When feasible, use the most intense ion in the mass
spectrum; when a less'intense ion is more characteristic and
sufficiently intense to provide necessary sensitivity, use
that ion to avoid possible interferences.
13. PRECISION AND ACCURACY |
13.1 To obtain method efficiency data (Table 2) and to indicate
anticipated single laboratory accuracy and precision data (Table 5)
for each listed analyte, seven 25-nt aliquots of each of two
solutions of reagent water containing known amounts of analytes
were analyzed with purge and |trap procedures and a packed column.
One solution contained 16 yg|of analyte per liter of solution; the
other contained 1.6 ug/L. Two direct injections of appropriate
volumes of secondary dilutiort standard were interspersed among
purged aliquots. To obtain the data in Table 5, one aliquot of
each of the two laboratory control standards was randomly selected
to be a solution with known true values of analytes. This aliquot
was treated as an external standard, and the other six aliquots of
each of the two solutions weri-e treated as samples.
13.1.1 Except for two listed^analytes, mean method efficiency
varied among analytes jfrom 25.0% to 118.7%. Those two
analytes, l,2-dibromo|3-chloropropane and bis(2-chloro-
isopropyl) ether, are!very inefficiently purged and were not
detected in aliquots containing 1.6 ug/L; mean method
efficiencies for these two analytes when purged from 16 ug/L
aliquots were 9.4% and 4.3%, respectively (Table 2).
Although for some applications these low efficiencies may
result in unacceptably high detection limits for those
32
-------
analytes, they can be measured with acceptable accuracy and
precision when present at a concentration of 16 ug/L (Table
5).
13.1.2 With these data, MDLs were calculated using the formula:
MDL = t
(n-1,1- = 0.99)
where:
t(n-l, 1- = 0.99) = Student's t value for the 99% confidence
level with n-1 degrees of freedom, where
n - number of replicates, and
s = standard deviation of replicate analyses.
33
-------
REFERENCES
1. Glaser, J. A., D. L. Foerst, 6. DJ McKee, S. A. Quave, and W. L. Budde,
"Trace Analyses for Wastewaters,"iEnviron. Sci. Techno!. 15, 1426, 1981,
2. "Carcinogens - Working With Carcinogens," Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health ,
Publication No. 77-206, Aug. 1977.
3. "OSHA Safety and Health Standards I General Industry," (29CFR1910),
Occupational Safety and Health Administration, OSHA 2206, (Revised,
January 1976). !
4. "Safety in Academic Chemistry Laboratories," American Chemical Society
Publication, Committee on Chemical Safety, 3rd Edition, 1979.
5. "The Determination of Halogenated !Chemicals in Water by the Purge and
Trap Method," Method 502.1, EPA 600/4-81-059, U.S. Environmental
Protection Agency, Office of Research and Development, Environmental
Monitoring and Support Laboratory, Cincinnati, OH, April 1981.
i
6. "The Analysis of Aromatic Chemicals in Water by the Purge and Trap
Method," Method 503.1, EPA 600/4r81-057. U.S. Environmental
Protection Agency, Office of Research and Development, Environmental
Monitoring and Support Laboratory.; Cincinnati, OH, May 1980.
34
-------
Table 1. Ion Abundance Criteria for £-Bromofluorobenzene
Mass
Ion Abundance Criteria
50
75
95
96
173
174
175
176
177
15 to 40% of mass 95
.30 to 60% of mass 95
Base Peak, 100% Relative Abundance
5 to 9% of mass 95
< 2% of mass 174
> 50% of mass 95
5 to 9% of mass 174
> 95% but < 101% of mass 174
5 to 9% of mass 176
35
-------
Table 2. Single Laboratory Method Efficiency Data3"for Purgeable
Organic Compounds Measured with GC/MS
Compound
c hi o ran ethane
vinyl chloride
methyl ene chloride
1 ,1-dichloroethene
bromochl orom ethane
trans-1 ,2-di chloroethene
chloroform
1 ,2-di chl oroethane
1 ,1 ,1-tri chl oroethane
carbon tetrachloride
bromodi chl orom ethane
1 ,1 ,2- tri chl oroethane
tri chloroethene
benzene
chl orodibromom ethane
cis-l,3-dichloropropene
fluoro benzene
: Rel.
Measured Ret.
Ion ' Time^
50 ; 0.10
I
62 ! 0.14
84 0.22
96 ' 0.28
128 0.30
96
83
62
97
117
83
97
130
78
129
75
96
0.31
0.44
0.50
0.59
0.62
0.66
0.79
0.84
0.88
0.88
0.90
1.00
True
Cone.
U9/L
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
Mean Method Rel .
Efficiency Std.
% Dev., %
108.5
53.8
118.7
81.9
93.8
88.1
68.8
65.0
50. Oc
98.8°
93.8
92.5
62.5
55.6
93.8
90.6
106.2
110.0
81.3
80.6
18.8°
50. Oc
100.0
106.9
106.2
96.3
58.8
53.8
25. QC
70. QC
100.0
95.6
15.2
13.6
4.9
7.6
5.1
7.9
5.8
6.2
30. 5C
12. 6C
3.8
2.1
12.6
7.1
3.8
2.9
2.2
1.9
5.9
5.4
33. 5C
15. 9°
3.0
1.2
2.9
2.2
6.0
11.3
31 .6C
11. 8P
7.4
11.1
36
-------
Table 2. (continued)
Compound
bromoform
1 ,1,2,2-tetrachloroethane
tetrachloroethene
tol uene
chloro benzene
1 ,2-dibromo-3-chloropropaned
4-bromof 1 uoro benzene
styrene
p-xyl ene
bis(2-chloroisopropyl ) etherd
1 ,3-di chloro benzene
1 ,2-di chl oro benzene
Measured
Ion
173
83
164
92
112
157
174
104
106
45
146
146
Rel.
Ret.
Time'3
1.10
1.29
1.31
1.42
1.52
1.70
1.82
1.93
1.97
2.08
2.19
2.20
True
Cone.
ug/L
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
1.6
16
16
1.6
16
1.6
16
Mean Method
Efficiency
%
39.4
35.0
28.1
25.0
106.2
107.5
100.0
102.5
93.8
96.3
__d
9.4C
93.8
93.8
68. 8C
86.9°
100.0
1 03. 1
4.3
75. QC
82. 5C
81.3
79.4
Rel.
Std.
Dev., %
7.0
6.3
5.9
6.3
0.0
4.6
3.2
1.5
3.5
2.2
__d
10. 3C
5.4
4.0
29. 2C
13. 3C
3.0
1.5
14.3
28. 3C
10. 3C
5.9
4.2
a Except as noted, data were produced by purging seven aliquots of reagent
water spiked with known amounts of listed compounds; calculations involved two
direct injections.
b GC column: 1.8 m x 2 mm ID glass packed with 1% SP-1000 on 60/80 mesh
carbopack B. Program: 45°C for 4 min; 8°C/min to 230°C.
Retention time relative to fluorobenzene, which has retention time of 11.1 min
under described GC conditions.
c Produced by analysis of six aliquots rather than seven.
d Compound is very inefficiently purged from water and was not detected in
aliquots of 1.6 yg/L solution.
37
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Table 3. Acceptable Storage Times3 for River and Drinking
Water Samples Containing Halogenated Aliphatic Analytes
Analyte
Demonstrated Acceptable
; Storage Time,
I Days
chloromethane
dichloromethane
carbon tetrachlori de
bromomethane
dibromomethane
bromoform
bromochloromethane
bromodi chloromethane
chlorodibromomethane
dichlorodifluoromethane
f 1 uorotri chl oromethane
chloroethane
1, 1-dichloroethane
1,2-dichloroethane
1,1,1-tri chloroethane
1,1,2-trichloroethane
1,1,1,2-tetrachloroethane
pentachloroethane
1,2-dibromoethane
chloroethylene (vinyl chloride)
1,1-di chl oroethyl ene
cis + trans-1,2-dichloroethylene
ci s-1,2-di chl oroethyl ene
1,1,2-trichloroethylene
1,1,2,2-tetrachl oroethyl ene
1,2-dichloropropane
1,3-dichloropropane
1,2,3-tri chl oro pro pane
3-chloroprop-l-ene (ally! chloride)
1,1-di chl oroprop-l-ene
2,3-di chl oro prop-1-ene
trans-l,3-dichloroprop-l-ene
cis-1,3-dichloroprop-l-ene
1-chlorohexane
chlorocyclohexane
1-chlorocyclohex-l-ene
21
27
27h
2b
21
27
21
27
27
27
27
21
27
27
21
27
21
27
21
27
27
21
27
27
21
21
21
2b
27h
6b
]h
lb
27
27
38
-------
Table 3 (continued)
Analyte
Demonstrated Acceptable
Storage Time,
Days
2-chloroethyl ethyl ether
2-chloroethylvinyl ether
bis-2-chloroethyl ether
bis-2»chloroisopropyl ether
27
27
9b
27
a These data were obtained by multiple analyses of raw river water and
carbon-filtered chlorinated tap water to which known amounts (0.20 to 0.50
ug/l.) of listed analytes had been added. Some samples were stored and
analyzed periodically over a 21-day period; others, over a 27-day period.
Data from "The Determination of Halogenated Chemicals in Water by the
Purge and Trap Method," Method 502.1, EPA 600/4-81-059, U.S. Environmental
Protection Agency, Office of Research and Development, Environmental
Monitoring and Support Laboratory, Cincinnati, OH, April 1981.
b Because of observed changes during storage, this number is the maximum
recommended storage time.
39
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-------
APPENDIX B
average
centimetre
cubic centimetre
day
degree Celsius
di ameter
equation
fi gure
foot
ga 11 on
gram
grams per litre
hour
hydrogen ion concentration,
negative logarithem of
inch
inside diameter
kilogram
logarithm (common)
logarithm (natural)
litre
maximum
metre
micro gram
mi crol i tre
micro-micro (prefix, use pico)
milliequi valent
milligram
millilitre
millimetre
millimetre of mercury (pressure)
millisecond
millivolt
minimum
mi nute
molal
molar
mole
month
(When followed by a date, use
Jan., Feb., March, April, May,
June, July, Aug., Sept., Oct.,
Nov., Dec. When there is no
date, spell out. Examples: Jan.
15, 1963; January 1963)
most probable number
nanometre (formerly milli
micron)
normal
number
D()nly when followed by a number
D
avg
cm
cm0
spell out
°9
dia (in figures and tables only)
Eq
Fig.
ft
gal
g
g/L
h
PH
in.
ID (in figures and tables only)
kg
log
log e or In
L
max
m
ug
uL
P
meq
mg
mL
mm
mm Hg
ms
mV
min
min
spell out
mol
spell
out
MPN
nm
N
No.D
43
-------
ortho
outside diameter
page
pages
para
parts per billion
parts per million
per
percent
pico (prefix)
pound
quart
reference
second
specific gravity
micrometer
volt
volume (of a publication)
watt
year
o ;
OD (in figures and tables only)
P-
pp.:
P '
ppb:
ppm;
usej the diagonal line in expressions
with unit symbols
P !
Ib
qi
Refi
s
sp gr
ym
V !
VolP
i
w
spe;ll out
44
-------
APPENDIX C: Journal Abbreviations
References to journals should be abbreviated according to the recommendations
in IS04-1972(E) and 833-1974(E) (see Format for Documentation). The follow-
ing list gives abbreviations for journals frequently cited in American
Chemical Society publications. Note that one-word titles are not abbreviated
(Chemistry, Nature, Science).
Ace. Chem. Res.
Acta Crystallogr., Sect. A
Acta Crystal!ogr., Sect. B
Adv. Chem. Ser.
AIChE J.
AIChE Symp. Serv.
Anal. Biochem.
Anal. Chem.
Anal. Chim. Acta
Anal. Lett.
Angew. Chem.
Ann. Chim. (Paris)
Antimicrob. Agents Chemother.
Appl. Environ. Microbiol.
Appl. Microbiol.
Appl. Opt.
Appl. Phys. Lett.
Appl. Polym. Symp.
Appl. Spectrosc.
Arch. Biochem. Biophys.
Aust. J. Chem.
Bacteriol. Proc.
Bacteriol. Rev.
Ber. Bunsenges. Phys. Chem.
Biochem. Biophys. Res. Commun.
Biol. Abstr.
Biochemistry
Biochem. 0.
Biochim. Biophys. Acta
Biochimie
Biofizika
Biokhimiya
Biopolymers
Bull. Chem. Soc. Opn.
Bull. Soc. Chim. Belg.
Bull. Soc. Chim. Fr.
Cancer Chemother. Rep., Part 1
Cancer Res.
Can. J. Biochem.
Can. J. Chem.
Can. J. Microbiol.
Carbohydr. Res.
Chem. Ber.
Chem. Biol. Interact
Chem. Eng. News
Chem. Eng. (N.Y.)
Chem. Ind. (London)
Chem. Ing.-Tech.
Chemistry
Chem. Lett.
Chem. Li sty
Chemotherapy (Tokyo)
Chem. Pharm. Bull.
Chem. Phys.
Chem. Phys. Lett.
CHEMTECH
Chem.-Ztg.
Chim. Ind. (Milan)
Clin. Chem. (Winston-Salem, N.C.)
Cold Spring Harbor Symp. Quant. Biol
Collect. Czech. Chem. Commun.
C.R. Acad. Sci., Ser. B
Dokl. Akad. Nauk SSSR
Electrochim. Acta
Endocrinology
Environ. Sci. Technol.
Eur. J. Biochem.
Exp. Cell Res.
Experientia
Faraday Discuss. Chem. Soc.
FEBS Lett.
Fed. Proc., Fed. Am. Soc. Exp. Biol.
Gazz. Chim. Ital.
Helv. Chim. Acta
Hoppe-Seyler's Z. Physiol. Chem.
Ind. Eng. Chem. Fund am.
Ind. Eng. Chem. Process Des. Dev.
Ind. Eng. Chem. Prod. Res. Dev.
IEEE J. Quantum Electron.
Inorg. Chem.
45
-------
Inorg. Chim. Acta
Inorg. Nucl. Chem. Lett.
Int. 0. Chem. Kinet.
Int. 0. Mass Spectrom. Ion Phys.
Int. 0. Quantum Chem.
Isr. 0. Chem.
Izv. Akad. Nauk SSSR, Ser. Khim
0. Agric. Food Chem.
J. Am. Chem. Soc.
J. Am. Oil Chem. Soc.
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