vvEPA
          United States
          Environmental Protection
          Agency
           Environmental Monitoring Systems
           Laboratory
           Research Triangle Park NC 2771 1
EPA-600/4-84-041
Apr 1984
          Research and Development
Compendium of
Methods for the
Determination  of
Toxic Organic
Compounds in
Ambient Air

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                                          EPA-600A-8l»-04l
                                          April  1984
 COMPENDIUM OF METHODS FOR THE DETERMINATION
  OF TOXIC ORGANIC COMPOUNDS IN AMBIENT AIR

                     by

                R. M. Riggin
       Battelle-Columbus Laboratories
               505 King Avenue
            Columbus, Ohio  43201
       Contract No. 68-02-3745 (WA-9)
            EPA Project Officer:
                L. J. Purdue
         Quality Assurance Division
 Environmental  Monitoring  Systems  Laboratory
    U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
 ENVIRONMENTAL MONITORING SYSTEM LABORATORY
     OFFICE OF RESEARCH AND DEVELOPMENT
    U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711

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                           Disclaimer
      This report has been reviewed by the Environmental  Monitoring
Systems Laboratory, U.  S.  Environmental Protection Agency, and
approved for publication.   Mention of trade names or commercial
products does not constitute endorsement or recommendation for
use.
                                ii

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                             CONTENTS
                                                            Page

FOREWARD                                                     iv
INTRODUCTION                                                 v
METHODS
     Tenax GC Adsorption                           Method TO-1
     Carbon Molecular Sieve Adsorption             Method TO-2
     Cryogenic Trapping                            Method TO-3
     High Volume Polyurethane Foam Sampling        Method TO-4
     Dinitrophenylhydrazine Liquid Impinger        Method TO-5
     Sampling

APPENDIX A - EPA Method
                                 111

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                            FOREWARD
      Measurement and monitoring research efforts are designed to
anticipate potential environmental  problems, to support regulatory
actions by developing an in-depth understanding of the nature and
processes that impact health and the ecology, to provide innovative
means of monitoring compliance with regulations, and to evaluate the
effectiveness of health and environmental protection efforts through
the monitoring of long-term trends.  The Environmental Monitoring
Systems Laboratory Research Triangle Park, North Carolina, has
responsibility for:  assessment of environmental monitoring
technology and systems; implementation of Agency-wide quality
assurance programs for air pollution measurement systems; and
supplying technical support to other groups in the Agency, including
the Office of Air and Radiation, the Office of Toxic Substances, and
the Office of Enforcement.

      Determination of toxic organic compounds in ambient air is a
complex task, primarily because of the wide variety of compounds of
interest and the lack of standardized sampling and analysis procedures.
This methods compendium has been prepared to provide a standardized
format for such analytical procedures.  A core set of five methods is
presented in the current document.   Addition of specific methods to
the compendium will occur as suitable methods become available.
Additionally, the current methods may be modified from time to time
as advancements are made.
                       Thomas  R.  Mauser,  Ph.D.
                              Director
             Environmental  Monitoring  Systems Laboratory
               Research Triangle Park, North Carolina
                                  iv

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                            INTRODUCTION
   This Methods Compendium has been prepared to provide regional,
state, and local environmental regulatory agencies, as well as other
interested parties, with specific guidance on the determination of
selected toxic organic compounds in ambient air.  Recently, a
Technical Assistance Document (TAD) was published which provided
guidance to such persons (1).  Based on the comments received
concerning the TAD the decision was made to begin preparation of a
Methods Compendium which would provide specific sampling and analysis
procedures, in a standardized format, for selected toxic organic
compounds.
   The current Methods Compendium consists of five procedures which
are considered to be of primary importance in current toxic organic
monitoring efforts.  Additional methods will be placed in the
compendium from time to time, as such methods become available.
The current methods were selected to cover as many compounds as
possible (i.e. multiple analyte methods were selected).  Future
methods are expected to be targeted towards specific compounds, or
small groups of compounds which, for various technical reasons,
cannot be determined by the more general methods.
   Each of the methods writeups is self contained (including pertinent
literature citations) and can be used independent of the remaining
portions of the Methods Compendium.  To the extent possible the
American Society for Testing and Materials (ASTM) standardized format
has been used, since most potential users are familiar with that
format.  Each method has been identified with a revision number and
date, since modifications to the methods may be required in the future.
   Nearly all the methods writeups have some flexibility in the procedure.
Consequently, it is the user's responsibility to prepare certain
standard operating procedures (SOPs) to be employed in that particular
laboratory.  Each method indicates those operations for which SOPs are
required.
   Table 1 summarizes the methods currently in the compendium.  As shown
in Table 1 the first three methods are directed toward volatile nonpolar
compounds.  The user should review the procedures as well  as the back-
ground material provided in the TAD (1) before deciding which of these
methods best meets the requirements of the specific task.
   Table 2 presents a partial listing of toxic organic compounds which
can be determined using the current set of methods in the  compendium.
Additional compounds may be determined by these methods, but the user
must carefully evaluate the applicability of the method before use.

Reference

1.  Riggin, R. M., "Technical Assistance Document for Sampling and
    Analysis of Toxic Organic Compounds in Ambient Air", EPA-600/4-
    83-027, U. S.  Environmental  Protection Agency, Research Triangle
    Park, North Carolina,  1983.

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             TABLE  1.  LIST OF METHODS IN THE COMPENDIUM
Method
Number
     Description
           Types  of
     Compounds  Determined
TO-1
TO-2
TO-3
Tenax GC Adsorption and
GC/MS Analysis
Carbon Molecular Sieve
Adsorption and GC/MS
Analysis
Cryogenic Trapping
and GC/FID or ECD
Analysis.
Volatile, nonpolar organics
(e.g. aromatic hydrocarbons,
chlorinated hydrocarbons)
having boiling points in the
range of 80 to 200°C.

Highly volatile, nonpolar
organics (e.g. vinyl chloride,
vinylidene chloride, benzene,
toluene) having boiling points
in the range of -15 to + 120°C.

Volatile.nonpolar organics having
boiling points in the range of
-10 to + 200°C.
TO-4
TO-5
High volume PUF
Sampling and GC/ECD
Analysis.

Dinitrophenylhydrazine
Liquid Impinger Sampling
and HPLC/UV Analysis.
Organochlorine pesticides and
PCBs
Aldehydes and Ketones

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                       TABLE  2.   LIST  OF  COMPOUNDS OF PRIMARY  INTEREST
         Compound
    Applicable
     Method(s)
                                                                Comments
 Acetaldehyde
 Acrolein
 Acrylonitrile
 Ally!  Chloride

 Benzaldehyde
 Benzene

 Benzyl Chloride

 Carbon Tetrachloride


 Chlorobenzene

 Chloroform
 Chloroprene
  (2-Chloro-l,3-butadiene)

 4,4'-DDE
 4,4'-DDT

 1,4-Dichlorobenzene

 Ethylene dichloride
  (1,2-Dichloroethane)

 Formaldehyde

 Methyl Chloroform
  (1,1,1-Trichloroethane)

 Methylene chloride

 Nitrobenzene

 Perchloroethylene
  (Tetrachloroethylene)

 Polychlorinated biphenyls
  (PCBs)
Propanal
 Toluene
TO-5
TO-5
TO-2, TO-3
TO-2, TO-3

TO-5
TO-1, TO-2, TO-3

TO-1, TO-3

(TO-1?) TO-2, TO-3


TO-1, TO-3

(TO-1?) TO-2, TO-3


TO-1, TO-3


TO-4
TO-4

TO-1, TO-3

(TO-1?) TO-2, TO-3


TO-5

(TO-1?) TO-2, TO-3


TO-2, TO-3

TO-1, TO-3

TO-1, (TO-2?), TO-3


TO-4

TO-5
TO-1, TO-2, TO-3
TO-3 yields better recovery
data than TO-2.

TO-3 yields better recovery
data than TO-2.

TO-3 yields best  recovery data.
Breakthrough volume is very low
using TO-1.
Breakthrough volume is very low
using TO-1.

The applicability of these methods
for chloroprene has not been
documented.
Breakthrough volume very low using
TO-1.
Breakthrough volume very low using
TO-1.
TO-2 performance has not been
documented for this compound.
                                         vii

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                               TABLE  2.   (Continued)
        r       .                 Applicable
	Compound	Methnd(«;)	Comments

Trichloroethylene            TO-1, TO-2, TO-3
Vinyl Chloride               TO-2, TO-3
Vinylidine Chloride          TO-2, TO-3
 (1,1-dichloroethene)

o,m,p-Xylene                 TO-1, TO-3
                                          viii

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                                 METHOD TOT                 Revision  1.0
                                                            April, 1984
     METHOD FOR THE DETERMINATION OF VOLATILE ORGANIC COMPOUNDS
             IN AMBIENT AIR USING TENAX® ADSORPTION AND
            GAS CHROMATOGRAPHY/MASS SPECTROMETRY (GC/MS)

1.    Scope

      1.1   The document describes a generalized protocol for collection
            and determination of certain volatile organic compounds
            which can be captured on Tenax® GC (poly(2,6-Diphenyl
            phenylene oxide)) and determined by thermal desorption
            GC/MS techniques. Specific approaches using these techniques
            are described in the literature (1-3).
      1.2   This protocol is designed to allow some flexibility in order
            to accommodate procedures currently in use.  However, such
            flexibility also results in placement of considerable
            responsibility with the user to document that such procedures
            give acceptable results (i.e. documentation of method performance
            within each laboratory situation is required).  Types of
            documentation required are described elsewhere in this method.
      1.3   Compounds which can be determined  by this method  are  nonpolar
            organics having boiling points in  the range of approximately
            80° -  200°C.   However, not all  compounds falling  into this
            category can  be determined.   Table 1  gives a listing  of
            compounds for which the method has been used.  Other compounds
            may yield  satisfactory results  but validation  by  the  individual
            user is required.

2.    Applicable  Documents

      2.1   ASTM  Standards:

            01356     Definitions of Terms Related to Atmospheric  Sampling
                     and  Analysis.
            E355      Recommended Practice for  Gas Chromatography  Terms and
                     Relationships.

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                               T01-2
      2.3   Other documents:

            Existing procedures (1-3).
            U.S.  EPA Technical Assistance Document (4).

3.    Summary of Protocol

      3.1   Ambient air is drawn  through a cartridge containing ^1-2
            grams of Tenax and certain  volatile organic  compounds are
            trapped on the resin  while  highly volatile organic compounds
            and most inorganic atmospheric constituents  pass through the
            cartridge.  The cartridge is then transferred to the
            laboratory and analyzed.
      3.2   For analysis the cartridge  is placed in a heated chamber and
            purged with an inert  gas.   The inert gas transfers the
            volatile organic compounds  from the cartridge onto a cold trap
            and subsequently onto the front of the GC column which is held
            at low temperature (e.g.  -  70°C).  The GC column temperature is
            then increased (temperature programmed) and  the components
            eluting from the column are  identified  and quantified  by mass
            spectrometry.  Component identification is normally accomplished,
            using a library search routine, on the basis of the GC retention
            time and mass spectral characteristics.  Less sophistacated
            detectors (e.g. electron capture or flame ionization) may be
            used for certain applications but their suitability for a given
            application must be verified by the user.
      3.3   Due to the complexity of ambient air samples only high resolution
            (i.e. capillary) GC techniques are considered to be acceptable
            in this protocol.

4.    Significance

      4.1   Volatile organic compounds  are emitted into  the atmosphere from
            a variety of sources  including industrial and commercial
            facilities, hazardous waste storage facilities, etc.  Many of
            these compounds are toxic;  hence knowledge of the levels of

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                                  TO!-3
            such materials in the ambient atmosphere is required in order
            to determine human health impacts.
      4.2   Conventional air monitoring methods (e.g. for workspace
            monitoring) have relied on carbon adsorption approaches with
            subsequent solvent desorption.   Such techniques allow
            subsequent injection of only a small portion, typically 1-5%
            of the sample onto the GC system.   However, typical
            ambient air concentrations of these compounds require a more
            sensitive approach.  The thermal  desorption process, wherein
            the entire sample is introduced into the analytical  (GC/MS)
            system fulfills this need for enhanced sensitivity.

5.    Definitions

      Definitions used in this document and any user prepared SOPs should
      be consistent with ASTM 01356(6).  All  abbreviations and symbols
      are defined with this document at the point of use.

6.    INTERFERENCES

      6.1   Only compounds having a similar mass spectrum and GC retention
            time compared to the compound of interest will interfere in
            the method.  The most commonly encountered interferences are
            structural isomers.
      6.2   Contamination of the Tenax cartridge with the compound(s)
            of interest is a commonly encountered problem in  the method.
            The user must be extremely careful in the preparation, storage,
            and handling of the cartridges throughout the entire sampling
            and analysis process to minimize  this problem.

 7.    Apparatus

       7.1   Gas Chromatograph/Mass Spectrometry system - should be capable
             of subambient temperature programming.  Unit mass resolution
             or better up to 800 amu.  Capable of scanning 30-440 amu region
             every 0.5-1 second.  Equipped with data system for instrument
             control as well as data acquisition, processing and storage.

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                             TO!-4
7.2   Thermal Desorption Unit - Designed to accommodate Tenax
      cartridges in use.  See Figure 2a or b.
7.3   Sampling System - Capable of accurately and precisely
      drawing an air flow of 10-500 ml/minute through the Tenax
      cartridge.  (See Figure 3a or b.)
7.4   Vacuum oven - connected to water aspirator vacuum supply.
7.5   Stopwatch
7.6   Pyrex disks - for drying Tenax.
7.7   Glass jar - Capped with Teflon-lined screw cap.   For
      storage of purified Tenax.
7.8   Powder funnel - for delivery of  Tenax into cartridges.
7.9   Culture tubes - to hold individual  glass Tenax cartridges.
7.10  Friction top can (paint can)  - to hold clean Tenax cartridges.
7.11  Filter holder - stainless steel  or aluminum (to accommodate
      1  inch diameter filter).   Other  sizes may be used if desired.
      (optional)
7.12  Thermometer - to record ambient  temperature.
7.13  Barometer (optional).
7.14  Dilution bottle - Two-liter with septum cap for standards
      preparation.
7.15  Teflon stirbar - 1 inch long.
7.16  Gas-tight glass syringes with stainless steel  needles -
      10-500 ul for standard injection onto GC/MS system..

7.17  Liquid micro!iter syringes -  5,50 ul for injecting neat
      liquid standards into dilution bottle.
7.18  Oven - 60 + 5°C for equilibrating dilution flasks.
7.19  Magnetic stirrer.
7.20  Heating mantel.
7.21  Variac
7.22  Soxhlet extraction apparatus  and glass thimbles - for purifying
      Tenax.
7.23  Infrared lamp - for drying Tenax.
7.24  GC column - SE-30 or alternative coating, glass capillary or
      fused silica.

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                                  T01-5
      7.25  Psychrometer - to determine ambient relative humidity.
            (optional).

8.    Reagents and Materials

      8.1   Empty Tenax cartridges - glass or stainless steel  (See
            Figure la or b).
      8.2   Tenax 60/80 mesh (2,6-diphenylphenylene oxide polymer),
      8.3   Glasswool - silanized.
      8.4   Acetone - Pesticide quality or equivalent.
      8.5   Methanol - Pesticide quality, or equivalent.
      8.6   Pentane - Pesticide quality or equivalent.
      8.7   Helium - Ultra pure, compressed gas. (99.9999%)
      8.8   Nitrogen - Ultra pure, compressed gas. (99.9999%)
      8.9   Liquid nitrogen.
      8.10  Polyester gloves - for handling glass Tenax cartridges.
      8.11  Glass Fiber Filter - one inch diameter, to fit in  filter holder.
            (optional)
      8.12  Perfluorotributylamine (FC-43).
      8.13  Chemical Standards - Neat compounds of interest.   Highest
            purity available.
      8.14  Granular activated charcoal - for preventing contamination of
            Tenax cartridges during storage.

9.    Cartridge Construction and Preparation

      9.1   Cartridge Design
            9.1.1   Several cartridge designs have been reported in  the
                    literature (1-3).  The most common (1) is  shown  in
                    Figure la.  This design minimizes contact  of the
                    sample with metal surfaces, which can lead to
                    decomposition in certain cases.  However,  a
                    disadvantage of this design is the need  to rigorously
                    avoid contamination of the outside portion of the
                    cartridge since the entire surface is subjected  to the
                    purge gas stream during the desorption porcess.

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                            T01-6
              Clean polyester gloves must be worn at all  times
              when handling such cartridges  and  exposure  of the
              open cartridge to ambient air must be minimized.
      9.1.2   A second common type of design (3) is shown in
              Figure Ib.   While this design  uses a metal  (stainless
              steel) construction, it eliminates the need to avoid
              direct contact with the exterior surface since only
              the interior of the cartridge  is purged.
      9.1.3   The thermal  desorption module  and  sampling  system
              must be selected to be compatible  with the  particular
              cartridge design chosen.   Typical  module designs
              are shown in Figures 2a and b.  These designs are
              suitable for the cartridge designs shown in Figures
              la and Ib,  respectively.

9.2   Tenax Purification
      9.2.1   Prior to use the Tenax resin is subjected to a
              series of solvent extraction and thermal treatment
              steps.  The  operation should be conducted in an area
              where levels of volatile organic compounds  (other than
              the extraction solvents used)  are  minimized.
      9.2.2   All glassware used in Tenax purification as well as
              cartridge materials should be  thoroughly cleaned by
              water rinsing followed by an acetone rinse  and dried
              in an oven  at 250°C.
      9.2.3   Bulk Tenax  is placed in a glass extraction  thimble
              and held in  place with a plug  of clean glasswool.
              The resin is then placed in the soxhlet extraction
              apparatus and extracted sequentially with methanol
              and then pentane for 16-24 hours (each solvent) at
              approximately 6 cycles/hour.  Glasswool for cartidge
              preparation  should be cleaned  in the same manner as
              Tenax.
      9.2.4   The extracted Tenax is immediately placed in an open
              glass dish  and heated under an infrared lamp for two

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                            TO!-7
              hours in a hood.  Care must be exercised to avoid
              over heating of the Tenax by the infrared lamp.
              The Tenax is then placed in a vacuum oven (evacuated
              using a water aspirator) without heating for one hour.
              An inert gas (helium or nitrogen) purge of 2-3
              ml/minute is used to aid in the removal of solvent
              vapors.  The oven temperature is then increased to
              110°C, maintaining inert gas flow and held for one
              hour.  The oven temperature control is then shut
              off and the oven is allowed to cool to room temperature.
              Prior to opening the oven, the oven is slightly
              pressurized with nitrogen to prevent contamination
              with ambient air.  The Tenax is removed from the oven
              and sieved through a 40/60 mesh sieve (acetone rinsed
              and oven dried) into a clean glass vessel.  If the Tenax
              is not to be used immediately for cartridge preparation
              it should be stored in a clean glass jar having a
              Teflon-lined screw cap and placed in a desiccator.

9.3   Cartridge Preparation and Pretreatment
      9.3.1   All  cartridge materials are pre-cleaned as described
              in Section 9.2.2.  If the glass cartridge design shown
              in Figure la is employed all  handling should be
              conducted wearing polyester gloves.
      9.3.2   The  cartridge is packed by placing a 0.5-lcm glass-
              wool  plug in the base of the  cartridge and then
              filling the cartridge to within approximately 1 cm
              of the top.   A 0.5-lcm glasswool  plug is placed in
              the  top of the cartridge.
      9.3.3   The  cartridges are  then thermally conditioned by
              heating for four hours at 270°C under an inert gas
              (helium) purge (100 - 200 ml/min).

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                                  TO!-8
            9.3.4   After the four hour heating period the cartridges
                    are allowed to cool.   Cartridges of the type shown
                    in Figure la are immediately placed (without cooling)
                    in clean culture tubes having Teflon-lined screw caps
                    with a glasswool cushion at both the top and the bottom.
                    Each tube should be shaken to ensure that the cartridge
                    is held firmly in place.  Cartridges of the type shown
                    in Figure Ib are allowed to cool to room temperature under
                    inert gas purge and are then closed with stainless steel
                    plugs.
            9.3.5   The cartridges are  labeled and  placed  in  a tightly
                    sealed metal  can (e.g.  paint can or similar friction
                    top container).  For cartridges  of the  type shown
                    in Figure la the culture tube,  not the cartridge,is
                    labeled.
            9.3.6   Cartridges should be  used for sampling within 2  weeks
                    after preparation and analyzed  within  two weeks  after
                    sampling.  If possible the cartridges  should be  stored
                    at -20°C in a clean freezer (i.e.  no solvent extracts
                    or other sources of volatile organics  contained  in the
                    freezer).

10.    Sampling
      10.1   Flow rate and Total Volume  Selection
            10.1.1   Each compound has a characteristic retention volume
                    (liters of air per  gram of adsorbent)  which must not
                    be exceeded.   Since the retention volume  is a function
                    of temperature, and possibly other sampling variables,
                    one must include an adequate margin of safety to
                    ensure good collection efficiency.  Some  considerations
                    and guidance in this regard are provided  in a recent
                    report (5).  Approximate breakthrough  volumes at 38°C
                    (100°F) in liters/gram of Tenax are provided in  Table 1.
                    These retention volume data are supplied only as rough
                    guidance and are subject to considerable variability,
                    depending on cartridge design as well  as sampling
                    parameters and atmospheric conditions.

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                      T01-9
10.1.2  To calculate the maximum total  volume of air which
        can be sampled use the following equation:

                 VMAX =  vbxw
                       1.5
where

        VMAX is tne calculated maximum total  volume in liters.
        Vfo   is the breakthrough volume for the least retained
             compound of interest (Table 1) in liters per gram
             of Tenax.
        W    is the weight of Tenax in  the cartridge, in grams.

        1.5 is a dimensionless safety factor to allow for
        variability in atmospheric conditions.  This factor
        is appropriate for temperatures in the range of
        25-30°C.  If higher temperatures are encountered the
        factor should be increased (i.e. maximum total  volume
        decreased).
10.1.3  To calculate maximum flow rate  use the following
        equation:
                          V
                   n       MAX v 1000
                   QMAX = -t— x IUUU
where

        QMAX   is *ne calculated maximum flow rate  in milli-
               leters per minute.
        t      is the desired sampling  time in minutes.   Times
               greater than 24 hours (1440 minutes) generally
               are unsuitable because the flow rate required
               is too low to be accurately maintained.
10.1.4  The maximum flow rate QMAX should yield a linear flow
        velocity of 50-500 cm/minute.  Calculate the linear
        velocity corresponding to the maximum flow rate
        using the following equation:
                   B = QMAX
                       irr

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                             T01-10
       where
               B  is the calculated linear flow velocity in
                  centimeters  per minute.
               r  is the internal  radius of the cartridge  in
                  centimeters.
               If B is  greater than 500 centimeters  per  minute
               either the total  sample volume  (VMAX)  should  be
               reduced  or the  sample flow  rate (QMAX)  should  be
               reduced  by increasing the collection  time.   If B  is
               less than 50 centimeters per minute the sampling  rate
               (QMAX) should be  increased  by reducing  the  sampling
               time.  The total  sample value (VMAX)  cannot be
               increased due to  component  breakthrough.
       10.1.4  The flow rate calculated as described  above defines
               the maximum flow rate allowed.   In general, one should
               collect  additional  samples  in parallel, for the same
               time period but at lower flow rates.   This  practice
               yields a measure  of quality control and is  further
               discussed in the  literature (5).   In  general,  flow
               rates 2  to 4 fold lower than the maximum  flow rate
               should be employed for the  parallel samples.   In
               all cases a constant flow rate  should  be  achieved
               for each cartridge since accurate integration  of  the
               analyte  concentration requires  that the flow be
               constant over the sampling  period.

10.2  Sample Collection

       10.2.1  Collection  of an accurately  known volume of air
              is  critical  to the accuracy  of  the results.  For
              this  reason  the use  of mass  flow  controllers,
              rather than  conventional needle  valves  or orifices
              is  highly recommended, especially at low flow
              velocities  (e.g.  less  than  100  milliliters/minute).
              Figure 3a illustrates  a sampling  system utilizing
              mass  flow controllers.  This system readily allows
              for collection  of  parallel  samples.  Figures 3b
              shows a  commercially available  system based on
              needle valve flow controllers.

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                      Toi-n
 10.2.2  Prior to  sample  collection  insure  that  the  sampling
         flow rate has been calibrated  over a  range  including
         the  rate  to  be used  for  sampling,  with  a  "dummy"
         Tenax cartridge  in place.   Generally  calibration
         is accomplished using a  soap bubble flow meter
         or calibrated wet test meter.   The flow calibration
         device is connected  to the  flow exit, assuming
         the  entire flow system is  sealed.   ASTM Method
         D3686 describes an appropriate calibration  scheme,
         not  requiring a sealed flow system downstream
         of the pump.
 10.2.3  The  flow rate should be  checked before  and  after
         each sample  collection.   If the sampling interval
         exceeds four hours the flow rate should be  checked
         at an intermediate point during sampling as well.
         In general,  a rotameter  should be  included, as
         showed in Figure 3b,  to  allow  observation of  the
         sampling flow rate without  disrupting the sampling
         process.
 10.2.4  To collect an air sample the cartridges are removed
         from the sealed container  just prior to initiation
         of the collection process.   If glass cartridges
         (Figure la)  are employed they must be handled
         only with polyester  gloves  and should not contact
         any  other surfaces.
10.2.5   A particulate filter and holder are placed  on
         the  inlet to the cartridges and the exit  end
         of the cartridge is  connected  to the  sampling
         apparatus.   In many  sampling situations the use
         of a filter  is not necessary if only  the  total
         concentration of a component is desired.  Glass
         cartridges of the type shown in Figure  la are
         connected using  teflon ferrules and Swagelok
         (stainless steel  or  teflon)  fittings.   Start  the
         pump and  record  the  following  parameters  on an
         appropriate  data  sheet (Figure 4):  data,  sampling
         location, time,  ambient  temperature,  barometric

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                     T01-12
        pressure,  relative  humidity,  dry gas  meter  reading
        (if applicable)  flow rate,  rotameter  reading  (if
        applicable),  cartridge  number and dry gas meter
        serial  number.
10.2.6  Allow the  sampler to operate  for the  desired  time,
        periodically  recording  the  variables  listed above.
        Check flow rate  at  the  midpoint  of the sampling
        interval  if longer  than four  hours.
        At the end of the sampling  period record the
        parameters listed in 10.2.5 and  check the flow
        rate and  record  the value.   If the flows at the
        beginning  and end of the sampling period differ
        by more than  10% the cartridge should be marked
        as suspect.
10.2.7  Remove the cartridges (one  at a  time) and place
        in the original  container (use gloves for glass
        cartridges).   Seal  the  cartridges or  culture  tubes
        in the friction-top can containing a  layer  of
        charcoal  and  package for immediate shipment to
        the laboratory for  analysis.   Store cartridges
        at reduced temperature  (e.g.  - 20°C)  before analysis
        if possible to maximize storage  stability.
10.2.8  Calculate  and record the average sample rate  for
        each cartridge according to the  following equation:
              Q.   Qi + Q2 + ---QN
               A "        N
where
        Q/\  = Average flow rate in ml/minute.
        Q], 0.2,	QN= Flow rates determined  at
        beginning, end, and immediate  points
        during sampling.

        N   = Number of points averaged.
10.2.9  Calculate and record the total volumetric flow for
        each cartridge using the following equation:
                        1000

-------
                                 T01-13
            where

                    Vm = Total  volume sampled in liters at measured
                         temperature and pressure,
                    T2 = Stop time.
                    T] = Start time.
                    T  = Sampling time = T£ - T],  minutes
            10.2.10 The total volume (Vs) at standard conditions,
                    25°C and 760 rnrnHg, is calculated from the
                    following equation:
                             'm x   76o *   273 + tA
            where

                    P/\ = Average  barometric pressure,  mrnHg
                    t/\ = Average  ambient temperature,  °C.
11.    6C/MS Analysis

      11.1   Instrument Set-up
            11.1.1   Considerable variation from one laboratory to
                    another is expected in terms of instrument configuration.
                    Therefore each laboratory must be responsible
                    for verifying that their particular system yields
                    satisfactory results.   Section 14 discusses specific
                    performance criteria which should be met.
            11.1.2   A block diagram of the typical GC/MS system
                    required for analysis  of Tenax cartridges  is
                    depicted in Figure 5.  The  operation  of such
                    devices is described in  11.2.4.  The thermal
                    desorption module must be designed to accommodate
                    the particular cartridge configuration.  Exposure
                    of the sample to metal surfaces should be
                    minimized and only stainless steel, or nickel metal
                    surfaces  should  be  employed.

-------
                      T01-14
        The volume of tubing and fittings leading from
        the cartridge to the GC column must be minimized
        and all areas must be well-swept by helium carrier
        gas.
11.1.3  The GC column inlet should  be capable  of being
        cooled to -70°C and subsequently increased rapidly
        to approximately 30°C.   This  can be most readily
        accomplished using a GC equipped with  subambient
        cooling capability (liquid  nitrogen) although
        other approaches such as manually cooling the
        inlet of the column in  liquid nitrogen may be
        acceptable.
11.1.4  The specific GC column  and  temperature program
        employed will be dependent  on the specific compounds
        of interest.  Appropriate conditions are described
        in the literature (1-3).  In  general a nonpolar
        stationary phase (e.g.  SE-30, OV-1) temperature
        programmed from 30°C to 200°C at 8°/minute will
        be suitable.  Fused silica  bonded phase columns
        are preferable to glass columns since  they are
        more rugged and  can be inserted directly into
        the MS ion source, thereby  eliminating the need
        for a GC/MS transfer line.
11.1.5  Capillary column dimensions of 0.3 mm  ID and  50
        meters long are generally appropriate  although
        shorter lengths may be  sufficient in many cases.
11.1.6  Prior to instrument calibration or sample analysis
        the GC/MS system is assembled as shown in Figure
        5.  Helium purge flows  (through the cartridge)
        and carrier flow are set at approximately 10 ml/
        minute and 1-2 ml/minute respectively.  If applicable,
        the injector sweep flow is  set at 2-4  ml/minute.

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                           T01-15
      11.1.7  Once the column and other system components are
              assembled and the various flows established the
              column temperature is increased to 250°C for
              approximately four hours (or overnight if desired)
              to condition the column.
      11.1.8  The MS and data system are set according to the
              manufacturer's instructions.   Electron impact
              ionization (70eV) and an electron multiplier gain
              of approximately 5 x 10^ should be employed.
              Once the entire GC/MS system has been setup the
              system is calibrated as described in Section 11.2.
              The user should prepare a detailed standard
              operating procedure (SOP) describing this process
              for the particular instrument being used.

11.2  Instrument Calibration

      11.2.1  Tuning and mass standarization of the MS system
              is performed according to manufacturer's instructions
              and relevant information from the user prepared
              SOP.  Perf1uorotributyl amine  should generally
              be employed  for this purpose.  The material
              is introduced directly into the ion source
              through a molecular leak.  The instrumental
              parameters (e.g. lens voltages, resolution,
              etc.) should be adjusted to give the relative
              ion abundances shown in Table 2 as well  as
              acceptable resolution and peak shape.   If
              these approximate relative abundances cannot
              be achieved, the ion source may require  cleaning
              according to manufacturer's instructions.
              In the event that the user's  instrument  cannot
              achieve these relative ion abundances, but
              is otherwise operating properly, the user
              may adopt another set of relative abundances
              as performance criteria.

-------
                   T01-16
        However,  these alternate  values  must  be  repeatable
        on a day-to-day basis.
11.2.2  After the mass standarization  and  tuning process
        has been  completed and  the  appropriate values
        entered into the data  system the user should
        then calibrate the entire system by introducing
        known quantities of the standard components
        of interest into the system.   Three alternate
        procedures may be employed  for the calibration
        process including 1) direct syringe injection
        of dilute vapor phase  standards, prepared
        in a dilution bottle, onto  the GC  column, 2)
        Injection of dilute vapor phase  standards
        into a carrier gas stream directed through the
        Tenax cartridge, and 3) introduction  of  permeation
        or diffusion tube standards onto a Tenax cartridge.
        The standards preparation procedures  for each
        of these  approaches are described  in  Section
        13.  The  following paragraphs  describe the
        instrument calibration  process for each  of
        these approaches.
11.2.3  If the instrument is to be  calibrated by direct
        injection of a gaseous  standard, a standard
        is prepared in a dilution bottle as described
        in Section 13.1.  The  GC column  is cooled
        to -70°C  (or, alternately,  a portion  of  the
        column inlet is manually cooled  with  liquid
        nitrogen).  The MS and  data system is set
        up for acquisition as  described  in the relevant
        user SOP.  The ionization filament should be turned
        off during the initial  2-3  minutes of the run to
        allow oxygen and other  highly  volatile components
        to elute.  An appropriate volume (less than 1 ml)
        of the gaseous standard is  injected onto the GC
        system using an accurately  calibrated gas tight syringe.

-------
                      T01-17

         The  system  clock  is  started and the column  is
         maintained  at  -70°C  (or  liquid nitrogen  inlet cooling)
         for  2 minutes.  The  column temperature is rapidly
         increased to the  desired  initial  temperature (e.g. 30°C).
         The  temperature program  is started at a  consistent
         time (e.g.  four minutes)  after injection.   Simultaneously
         the  ionization  filament  is  turned on  and data  acquisition
         is initiated.  After the  last component  of  interest has
         eluted  acquisiton is terminated and the  data is processed
         as described in Section  11.2.5.   The standard injection
         process is  repeated  using different standard volumes as
         desired.
11.2.4   If  the  system  is  to be calibrated by  analysis of
         spiked  Tenax cartridges  a set of  cartridges is
         prepared as described in Sections 13.2 or 13.3.
         Prior to analysis the cartridges  are  stored as
         described in  Section 9.3. If  glass cartridges  (Figure  la)
         are  employed  care must be taken  to avoid direct
         contact, as described earlier.   The GC column  is
         cooled  to -70°C,  the collection  loop  is  immersed  in
         liquid  nitrogen  and the  desorption module is
         maintained  at  250°C.  The inlet  valve  is placed  in  the
         desorb  mode and  the standard  cartridge is placed  in
         the  desorption module, making certain  that  no  leakage
         of purge gas  occurs.  The cartridge is purged
         for 10  minutes and then  the  inlet valve  is  placed  in
         the  inject  mode  and the  liquid  nitrogen  source  removed
         from the collection trap.  The  GC column is maintained
         at -70°C for  two minutes and  subsequent  steps  are  as
         described in  11.2.3. After  the  process is complete  the
         cartridge is  removed from the desorption module  and
         stored  for subsequent use as  described in Section  9.3.

-------
                            T01-18
      11.2.5   Data processing for instrument calibration  involves
               determining retention times,  and integrated characteristic
               ion intensities for each of the compounds of interest.
               In addition, for at least one chromatographic run,the
               individual mass spectra should be inspected and
               compared  to reference spectra to ensure  proper
               instrumental  performance.   Since the steps  involved
               in data processing  are highly instrument specific,  the
               user should prepare a SOP describing the process  for
               individual  use.   Overall  performance criteria for
               instrument calibration are provided  in Section 14.   If
               these criteria  are  not achieved the  user should refine
               the instrumental  parameters and/or operating
               procedures to meet  these  criteria.

11.3  Sample Analysis

      11.3.1   The sample analysis process is identical  to that
               described in Section 11.2.4 for the  analysis of standard
               Tenax cartridges.
      11.3.2   Data processing for sample data generally involves
               1) qualitatively determining  the presence or absence
               of each component of interest on the basis  of a set
               of characteristic ions and  the  retention  time using
               a reverse^search software routine,  2) quantification
               of each identified  component  by integrating the intensity
               of a characteristic ion and comparing the value to
               that of the calibration standard, and 3) tentative
               identification  of other components observed using a
               forward  (library)  search  software routine.   As for
               other user specific processes, a SOP should be prepared
               describing the  specific operations for each individual
               laboratory.

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                               TO!-19
12.    Calculations

      12.1   Calibration Response Factors

            12.1.1  Data from calibration standards is used  to calculate
                    a response factor for each component of  interest.
                    Ideally the process involves analysis of at least
                    three calibration levels  of each component during  a
                    given day and determination of the response
                    factor (area/nanogram injected) from the linear
                    least squares fit of a plot of nanograms injected
                    versus area (for the characteristic ion).
                    In  general  quantities of  component greater
                    than 1000 nanograms should not be  injected
                    because of column overloading and/or MS  response
                    non linearity.
            12.1.2  In  practice the  daily routine may  not always
                    allow analysis of three such calibration standards.
                    In  this situation calibration data  from  consecutive
                    days may be pooled  to yield  a response factor,
                    provided that  analysis of  replicate  standards
                    of  the same concentration  are shown  to agree
                   within 20% on  the consecutive days.  One standard
                    concentration, near the midpoint of the  analytical
                    range  of interest,  should  be  chosen  for  injection
                    every  day to determine day-to-day  response
                    reproducibility.
            12.1.3   If  substantial nonlinearity  is  present in
                    the  calibration  curve a nonlinear  least  squares
                    fit  (e.g. quadratic)  should  be  employed.
                    This process involves fitting  the data to
                    the  following  equation:
                          Y  = A +  BX  + CX2
           where
                    Y = peak area
                   X = quantity of component, nanograms
                   A,B, and C are coefficients in the equation

-------
                               TO 1-20
     12.2  Analyte  Concentrations
           12.2.1
           where
           12.2.2
           12.2.3
           where
Analyte quantities on a sample cartridge are calculated
from the following equation:

     YA  = A  +  BXA  + CXA
YA  is the area of the analyte characteristic ion for
    the sample cartridge.
XA  is the calculated quantity of analyte on the sample
    cartridge, in nanograms.
A,B, and C are the coefficients calculated from the
calibration curve described in Section 12.1.3.
If instrumental response is essentially linear over the
concentration range of interest a linear equation
(C=0 in the equation above) can be employed.
Concentration of analyte in the original air sample is
calculated from the following equation:

             r   XA
                    CA  is  the  calculated  concentration  of  analyte  in
                        nanograms  per liter.
                    Vs  and X.  are  as previously defined  in Section
                    10.2.10 and 12.2.1, respectively.
13.    Standard Preparation
      13.1   Direct Injection
            13.1.1  This process  involves  preparation  of  a  dilution
                    bottle containing the  desired  concentrations
                    of compounds  of interest  for direct injection
                    onto the GC/MS system.

-------
                           T01-21
  13.1.2   Fifteen  three-millimeter diameter glass beads
          and  a  one-inch  Teflon  stirbar are placed  in a
          clean  two-liter glass  septum capped bottle and
          the  exact  volume is determined by weighing the
          bottle before and after filling with deionized water.
          The  bottle is then rinsed with acetone and dried at 200°C.
  13.1.3   The  amount of each standard to be injected into the
          vessel is  calculated from the desired injection quantity
          and  volume using the following equation:

                           WT _  -
                           T "vl
      where
               Wj is the total  quantity of analyte to  be injected
                  into the bottle in milligrams
               Wj  is the desired weight of analyte to  be injected
                  onto the GC/MS system or spiked  cartridge  in
                  nanograms
               Vi  is the desired GC/MS or  cartridge injection
                  volume (should not exceed  500)  in microliters.
               VB  is total volume of dilution bottle determined
                  in 13.1.1, in  liters.
        13.1.4 The volume of the neat standard  to  be injected
                  into the dilution  bottle is determined using
                  the following  equation:
                                WT
where
               Vj is the total  volume of neat  liquid  to  be  injected
                  in microliters.
                d is the density of the  neat standard  in  grams per
                  milliliter.

-------
                         T01-22
13.1.6  The bottle is placed in a 60°C oven for at
        least 30 minutes prior to removal of a vapor
        phase standard.
13.1.7  To withdraw a standard for GC/MS injection
        the bottle is removed from the oven and stirred
        for 10-15 seconds.  A suitable gas-tight microber
        syring warmed to 60°C, is inserted through
        the septum cap and pumped three times slowly.
        The appropriate volume of sample (approximately 25%
        larger than the desired injection volume) is drawn
        into the syringe and the volume is adjusted to the
        exact value desired and then immediately injected
        over a 5-10 seconds period onto the GC/MS system as
        described in Section 11.2.3.

13.2  Preparation of  Spiked  Cartridges  by  Vapor  Phase  Injection
      13.2.1  This process involves preparation of a dilution
             bottle containing the desired concentrations
             of  the compound(s) of interest as described
             in  13.1 and injecting the desired volume of
             vapor into a flowing inert gas stream directed
             through a clean Tenax cartridge.
       13.2.2 A helium purge system  is  assembled wherein
             the helium flow 20-30 mL/minute is passed
             through a stainless steel Tee fitted with
             a septum  injector.  The clean Tenax cartridge
             is  connected downstream of the  tee using
             appropriate  Swagelok fittings.  Once the cartridge
              is  placed  in the  flowing  gas  stream the  appropriate
              volume  vapor standard,  in the dilution  bottle,
              is  injected  through  the  septum  as  described  in
              13.1.6.   The  syringe  is  flushed several  times
              by alternately filling the  syringe with carrier
              gas and displacing the contents into  the flow
              stream, without removing the syringe  from the  septum.
              Carrier flow is maintain through the  cartridge for
              approximately 5 minutes after injection.

-------
                                TO!-23

      13.3  Preparation of Spiked Traps Using Permeation or Diffusion
            tubes
            13.3.1  A flowing stream of inert gas containing known
                    amounts of each compound of interest is generated
                    according to ASTM Method 03609(6).  Note that
                    a method of accuracy maintaining temperature
                    within + 0.1°C is required and the system
                    generally must be equilibrated for at least
                    48 hours before use.
            13.3.2  An accurately known volume of the standard
                    gas stream (usually 0.1-1 liter) is drawn
                    through a clean Tenax cartridge using the
                    sampling system described in Section 10.2.1,
                    or a similar system.  However, if mass flow
                    controllers are employed they must be calibrated
                    for the carrier gas used in Section 13.3.1
                    (usually nitrogen).  Use of air as the carrier
                    gas for permeation systems is not recommended,
                    unless the compounds of interest are known
                    to be highly stable in air.
            13.3.3  The spiked cartridges are then stored or immediately
                    analyzed as in Section 11.2.4.

14.   Performance Criteria and Quality Assurance

     This section summarizes quality assurance (QA) measures and
     provides guidance concerning performance criteria which should  be
     achieved within each laboratory.  In many cases the specific
     QA procedures have been described within the appropriate section
     describing the particular activity (e.g. parallel sampling).

-------
                          TO!-24

14.1    Standard Opreating Procedures  (SOPs)
       14.1.1   Each user should generate  SOPs  describing  the
               following activities as  they  are  performed
               in their laboratory:
               1) assembly,  calibration,  and operation  of
                  the sampling system,
               2) preparation, handling and  storage  of  Tenax
                  cartridges,
               3) assembly and operation  of  GC/MS system  including
                  the thermal desorption  apparatus and  data
                  system, and
               4) all aspects of data recording  and  processing.
       14.1.2  SOPs should provide specific  stepwise instructions
               and should be readily  available to, and  understood
               by the laboratory personnel  conducting the
               work.

14.2   Tenax Cartridge Preparation

       14.2.1  Each batch of Tenax cartridges  prepared  (as
               described in Section 9)  should  be checked  for
               contamination by analyzing one  cartridge immediately
               after preparation.  While analysis can be  accomplished
               by GC/MS, many  laboratories may chose to use
               GC/FID due to logistical and cost considerations.
       14.2.2  Analysis  by GC/FID is accomplished as described
               for GC/MS  (Section 11) except for use of FID
               detection.

-------
                          TO!-25

       14.2.3  While acceptance criteria  can vary depending
               on the components of interest, at a minimum
               the clean cartridge should be demonstrated
               to contain less  than one fourth of the  minimum
               level of interest for each component.   For
               most compounds the blank level should be  less
               than 10 nanograms per cartridge in order  to
               be acceptable.  More rigid criteria may be
               adopted, if necessary, within a specific  laboratory.
               If a cartridge does not meet  these acceptance
               criteria the entire lot should be rejected.

14.3   Sample Collection

       14.3.1  During each sampling event at least one clean
               cartridge will accompany the  samples to the
               field and back to the laboratory, without being
               used for sampling, to serve as a field  blank.
               The average amount of material found on the
               field blank cartridge may  be  subtracted from
               the amount found on the actual samples.   However,
               if the blank level is greater than 25%  of the
               sample amount, data for that  component  must
               be identified as suspect.
       14.3.2  During each sampling event at least one set
               of parallel samples (two or more samples  collected
               simultaneously)  will be collected, preferably
               at different flow rates as described in Section
               10.1.  If agreement between parallel samples
               is not generally within +  25/S the user  should
               collect parallel samples on a much more frequent
               basis (perhaps for all sampling points).  If
               a trend of lower apparent  concentrations  with
               increasing flow rate is observed for a  set

-------
                          TOT-26
               of  parallel  samples one should consider using
               a reduced  flow rate and longer sampling interval
               if  possible.   If  this practice does not improve
               the reproducibility further evaluation of the
               method  performance for the compound of interest
               may be  required.
       14.3.3   Backup  cartridges (two cartridges  in  series)
               should  be  collected with each sampling event.
               Backup  cartridges should contain less than
               20% of  the amount of components of interest
               found  in the front cartridges, or  be  equivalent
               to  the  blank cartridge level, whichever is
               greater.   The frequency of use of  backup cartridges
               should  be  increased if increased flow rate
               is  shown to yield reduced component levels
               for parallel sampling.  This practice will
               help to identify  problems arising  from breakthrough
               of  the  component  of interest during sampling.

14.4   GC/MS Analysis

       14.4.1   Performance criteria for MS  tuning and mass
               calibration have  been  discussed  in Section
               11.2 and Table 2. Additional criteria may
               be  used by the laboratory  if desired.  The
               following  sections provide performance guidance
               and suggested criteria for determining the
               acceptability of  the GC/MS system.
       14.4.2  Chromatographic efficiency should  be  evaluated
               using spiked Tenax cartridges  since this  practice
               tests the  entire  system.   In  general  a  reference
               compound such as  perfluorotoluene  should  be
               spiked onto a cartridge  at the  100 nanogram
               level as described in  Section  13.2 or 13.3.
               The cartridge is  then  analyzed  by GC/MS  as

-------
                   T01-27
       described  in Section  11.4.  The perfluorotoluene (or
       other  reference compound) peak is then plotted on an
       expanded time  scale so that its width at 10% of the
       peak can be calculated, as shown in Figure 6.  The
       width  of the peak at  10% height should not exceed
       10  seconds.  More stringent criteria may be required
       for certain applications.  The assymmetry factor
       (See Figure 6) should be between 0.8 and 2.0.  The
       assymmetry factor for any polar or reactive compounds
       should be  determined  using the process described above.
       If  peaks are observed that exceed the peak width or
       assymmetry factor criteria above, one should inspect
       the entire system to determine if unswept zones or
       cold spots are present in any of the fittings and
       is  necessary.  Some laboratories may chose
       to  evaluate column performance separately by
       direct injection  of a test mixture onto the
       GC  column. Suitable  schemes  for column evaluation
       have  been  reported in the  literature (7).
       Such  schemes  cannot be  conducted by placing
       the substances onto Tenax  because many of
       the compounds  (e.g. acids, bases, alcohols)
       contained  in  the  test mix  are not retained,
       or  degrade, on Tenax.
14.4.3 The system detection  limit for each component
        is  calculated  from the  data  obtained for
       calibration standards.   The  detection  limit
        is  defined as

                DL =  A +  3.3S

-------
                   T01-28
where
        DL is the calculated detection limit in
           nanograms  injected.
        A is the intercept calculated in Section
           12.1.1 or  12.1.3.
        S is the standard deviation of replicate
           determinations of the lowest level  standard
           (at least  three such determinations are
           required.
        In general the detection limit should  be 20
        nanograms or  less and for many applications
        detection limits of 1-5 nanograms may be required.
        The lowest level standard should yield a signal
        to noise ratio, from the total ion current response,
        of approximately 5.
14.4.4  The relative  standard deviation for replicate
        analyses of cartridges spiked at approximately
        10 times the  detection limit should be 20%
        or less.  Day to day relative standard deviation
        should be 25% or less.
14.4.5  A useful performance evaluation step is the
        use of an internal standard to track system
        performance.   This is accomplished by spiking
        each cartridge, including blank, sample, and
        calibration cartridges with approximately 100
        nanograms of a compound not generally present
        in ambient air (e.g. perfluorotoluene).  The
        integrated ion intensity for this compound
        helps to identify problems with a specific
        sample.  In general the user should calculate
        the standard deviation of the internal standard
        response for a given set of samples analyzed
        under identical tuning anc1 calibration conditions.
        Any sample giving a value greater than _+ 2
        standard deviations from the mean (calculated

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                              T01-31
  TABLE 1.  RETENTION VOLUME ESTIMATES FOR COMPOUNDS ON TENAX
                                      ESTIMATED RETENTION VOLUME AT
        COMPOUND                      100°F (38°C)-LITERS/GRAM

Benzene                                            19
Toluene                                            97
Ethyl Benzene                                     200
Xylene(s)                                       -v 200
Cumene                                            440
n-Heptane                                          20
1-Heptene                                          40

Chloroform                                          8
Carbon Tetrachloride                                8
1,2-Dichloroethane                                 10
1,1,l-Trichloroethane                               6
Tetrechloroethylene                                80
Trichloroethylene                                  20
1,2-Dichloropropane                                30
1,3-Dichloropropane                                90
Chlorobenzene                                     150
Bromoform                                         100
Ethylene Dibromide                                 60
Bromobenzene                                      300

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                            TO!-32
TABLE 2.  SUGGESTED PERFORMANCE CRITERIA FOR RELATIVE
          ION ABUNDANCES FROM FC-43 MASS CALIBRATION
                                    % RELATIVE
       M/E                           ABUNDANCE

         51                          1.8+0.5

         69                          100

       100                          12.0 + 1.5

       119                          12.0 + 1.5

       131                          35.0 + 3.5

       169                          3.0 + 0.4

       219                          24.0 + 2.5

       264                           3.7 + 0.4

       314                           0.25 + 0.1

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            TO!-29
excluding that particular sample) should be
identified as suspect.   Any marked change in
internal standard response may indicate a need
for instrument recalioration.

-------
                                  T01-30

                                REFERENCES
1.   Krost, K. J., Pellizzari, E.  D.,  Walburn,  S.  6.,  and  Hubbard,  S.  A.,
     "Collection and Analysis of Hazardous Organic Emissions",
     Analytical  Chemistry. 54, 810-817,  1982.

2.   Pellizzari, E.  0.  and Bunch,  J.  E., "Ambient  Air  Carcinogenic  Vapors-
     Improved Sampling  and Analytical  Techniques and Field Studies",
     EPA-600/2-79-081,  U.S.  Environmental  Protection Agency,  Research
     Triangle Park,  North Carolina,  1979.

3.   Kebbekus, B. B. and Bozzelli, J.  W.,  "Collection  and  Analysis  of
     Selected Volatile  Organic Compounds in Ambient Air",  Proc.  Air
     Pollution Control  Assoc., Paper No. 82-65.2.   Air Poll.  Control
     Assoc., Pittsburgh, Pennsylvania, 1982.

4.   Riggin, R.  M.,  "Technical Assistance  Document for Sampling  and
     Analysis of Toxic  Organic Compounds in Ambient Air",  EPA-600/
     4-83-027, U.S.  Environmental  Protection Agency, Research Triangle
     Park, North Carolina, 1983.

5.   Walling, J. F., Berkley, R. E.,  Swanson,  D. H., and Toth, F. J.
     "Sampling Air for  Gaseous Organic Chemical-Applications  to  Tenax",
     EPA-600/7-54-82-059, U.S. Environmental  Protection Agency,  Research
     Triangle Park,  North Carolina,  1982.

6.   Annual Book of ASTM Standards,  Part 11.03, "Atmospheric Analysis",
     American Society for Testing  and  Material,  Philadelphia,
     Pennsylvania.

7.   Grob, K., Jr.,  Grob, 6.,-and  Grob,  K., "Comprehensive Standardized
     Quality Test for Glass Capillary  Columns",  J.  Chromatog., 156,
     1-20, 1978.

-------
                               T01-33
                                         Tenax
                                         ~1.5 Grams (6 cm Bed Depth)
                            • Glass Wool Plugs
                             (0.5 cm Long)
                                      Glass Cartridge
                                      (13.5 mm OD x
                                      100 mm Long)
                                                                 idae  	A
                           .(a) Glass Cartridge
1/2" to
1/8"
Reducing
Union
            Glass Wool
            Plugs
            (0.5 cm Long)
                                          \
1/8" End Cap,
Tenax
~1.5 Grams (7 cm Bed Depth)

         (b)  Metal Cartridge
                                              Metal Cartridge
                                              (12.7 mm OD x
                                              100 mm Long)
                 FIGURE 1.  TENAX CARTRIDGE DESIGNS

-------
                                            T01-34
                            Teflon
                            Compression
                            Seal
                              Purge
                              Gas
                            Cavity for •
                            Tenax
                            Cartridge
                            Latch for
                            Compression
                            Seal
                                                       Effluent to
                                                       6-Port Valve
                                                              To GC/MS
                                             Liquid
                                             Nitrogen
                                             Coolant

                                 (a)  Glass Cartridges (Compression Fit)
Purge
Swagelok
End Fittings
                                           Tenax
                                           Trap
                                      z
Heated
Block
                                              To GC/MS
                                                Vent
                                                                               Liquid
                                                                               Nitrogen
                                                                               Coolant
                                 (b) Metal Cartridges (Swagelok Fittings)
                       FIGURE 2. TENAX CARTRIDGE DESORPTION MODULES

-------
                                           TO!-35
                                                          D
                       Vent
                                                               Couplings
                                                               to Connect
                                                               Tenax
                                                               Cartridges
                                       (a) Mass Flow Control
                         Rotometer
Vent
 Dry
 Test
Meter
                                      V
                                                       Pump
Coupling to
Connect Tenax
Cartridge
                                     Needle
                                     Valve
                                      (b) Needle Valve Control
                      FIGURE 3. TYPICAL SAMPLING SYSTEM CONFIGURATIONS

-------
                                         TOT - 36
                                SAMPLING DATA SHEET
                            (One Sample Per Data Sheet)
PROJECT:

SITE:
DATE(S) SAMPLED:
LOCATION:
TIME PERIOD SAMPLED:

OPERATOR:
INSTRUMENT MODEL N0:_

PUMP SERIAL NO:	

SAMPLING DATA
CALIBRATED BY:
                        Sample Number:
                 Start Time:
 Stop Time:
Time
1.
2.
3.
4.
N.
Dry Gas
Meter
Reading





Rotameter
Reading





Flow
Rate,*Q
ml /Min





Ambient
Temperature
°C





Barometric
Pressure,
mmHg





Relative
Humidity, %





Comments





   Total  Volume  Data**
           Vm = (Final - Initial) Dry Gas Meter Reading, or

              -  Ql + 0.2 + 0.3---QN  x       1	,	
                         R1000 x (Sampling Time  in Minutes)
                                  Liters

                                  Liters
     * Flowrate from rotameter or soap bubble calibrator
       (specify which).
    ** Use data from dry gas meter if available.
                       FIGURE 4.   EXAMPLE SAMPLING DATA SHEET

-------
Purge
Gas
                                TO!-37
         Thermal
         Desorption
         Chamber
                      6-Port High-Temperature
                      Valve
                                   Capillary
                                     Gas
                                Chromatograph
                             Mass
                          Spectrometer
 Data
System
 Carrier
 Gas
      Vent
Freeze Out Loop
              Liquid
              Nitrogen
              Coolant
               FIGURE 5. BLOCK DIAGRAM OF ANALYTICAL SYSTEM

-------
               TO!-38
                          BC
         Asymmetry Factor * —

Example Calculation:

     Peak Height - DE = 100 mm
     10% Peak Height - BD - 10 mm
     Peak Width at 10% Peak Height - AC - 23 mm
         AB • 11  mm
         BC *12 mm
                               12
     Therefore: Asymmetry Factor • — « 1.1
 FIGURE 6.  PEAK ASYMMETRY CALCULATION

-------
                              METHOD T02                 Revision 1.0
                                                         April, 1984

     METHOD FOR THE DETERMINATION OF VOLATILE ORGANIC COMPOUNDS IN
          AMBIENT AIR  BY  CARBON MOLECULAR  SIEVE ADSORPTION AND
          GAS  CHROMATOGRAPHY/MASS  SPECTROMETRY  (GC/MS)
1.    Scope

     1.1   This document describes a procedure for collection and
           determination of selected volatile organic compounds
           which can be captured on carbon molecular sieve (CMS)
           adsorbents and determined by thermal  desorption GC/MS
           techniques.
     1.2   Compounds which can be determined by this method are
           nonpolar and nonreactive organics having boiling points
           in the range -15 to +120°C.   However, not all  compounds
           meeting these criteria can be determined.  Compounds for
           which the performance of the method has been documented
           are listed in Table 1.  The  method may be extended to
           other compounds but additional validation by the user
           is required.  This method has been extensively used in
           a single laboratory.   Consequently, its general applicability
           has not been thoroughly documented.

2.    Applicable Documents

     2.1   ASTM Standards
           D 1356 Definitions of Terms  Related to Atmospheric Sampling
           and Analysis.
           E 355 Recommended Practice for Gas Chromatography Terms
           and Relationships.

     2.2   Other Documents
           Ambient Air Studies (1,2).

           U.S.  EPA Technical  Assistance
           Document (3).

-------
                                 T02-2
3.    Summary of Method

     3.1    Ambient air is drawn through a  cartridge containing ^0.4
           of a carbon molecular sieve (CMS)  adsorbent.   Volatile
           organic compounds are captured  on  the  adsorbent while
           major inorganic atmospheric constituents pass  through
           (or are only partially retained).   After sampling,  the
           cartridge is returned to the laboratory for analysis.
     3.2   Prior to analysis the cartridge is purged with 2-3 liters of
           pure, dry air (in the same direction as sample flow) to
           remove adsorbed moisture.
     3.3   For analysis the cartridge is heated to 350°-400°C, under
           helium purge and the desorbed organic compounds are
           collected in a specially designed  cryogenic trap.   The
           collected organics are then flash evaporated onto a
           capillary column GC/MS system (held at -70°C).  The
           individual components are identified and quantified during
           a temperature programmed chromatographic run.
     3.4   Due to the complexity of ambient air samples,  only high
           resolution (capillary column) GC techniques are
           acceptable for most applications of the method.

4.   Significance

     4.1   Volatile organic compounds are emitted into the atmosphere
           from a variety of sources including industrial and commercial
           facilities, hazardous waste storage and treatment facilities,
           etc.  Many of these compounds are toxic; hence knowledge of
           the concentration of such materials in the ambient atmosphere
           is required in order to determine human health impacts.
     4.2   Traditionally air monitoring methods for volatile organic
           compounds have relied on carbon adsorption followed by
           solvent desorption and GC analysis.  Unfortunately, such
           methods are not  sufficiently sensitive for ambient air
           monitoring, in most cases, because only a  small portion of

-------
                                T02-3

           the  sample  is  injected  onto  the GC system.   Recently on-line
           thermal  desorption methods,  using organic  polymeric adsorbents
           such as  Tenax® GC, have  been  used for ambient air monitoring.
           The  current method uses  CMS  adsorbents  (e.g. Spherocarb®)
           to capture  highly volatile organics  (e.g.  vinyl chloride)
           which are not  collected  on Tenax®.   The  use  of on-line thermal
           desorption  GC/MS yields  a sensitive, specific analysis
           procedure.

5.   Definitions

     Definitions used  in this  document  and any user prepared  SOPs should
     be consistent with ASTM D1356 (4).  All abbreviations and symbols
     are defined with  this document at  the point  of use.

6.   Interferences

     6.1   Only compounds having a mass spectrum  and GC retention
           time similar to the compound of interest will  interfere
           in  the method.  The  most commonly encountered  interferences
           are  structural isomers.
     6.2   Contamination of the CMS cartridge  with the  compound(s)
           of  interest can be  a problem in the  method.  The user  must
           be  careful  in the preparation,  storage,  and  handling of  the
           cartridges  through  the entire process  to minimize  contamination.

-------
                                 T02-4
7.   Apparatus

     7.1   Gas Chromatograph/Mass Spectrometry system - must be capable
           of subambient temperature programming.   Unit mass resolution
           to 800 amu.   Capable of scanning 30-300 amu region every
           0.5-0.8 seconds.   Equipped with data system for instrument
           control as well  as data acquisition, processing and storage.
     7.2   Thermal Desorption Injection Unit - Designed to accommodate
           CMS cartridges in use (See Figure 3) and including cryogenic
           trap (Figure 5)  and injection valve (Carle Model  5621
           or equivalent).
     7.3   Sampling System  - Capable of accurately and precisely
           drawing an air flow of 10-500 ml/minute through the CMS
           cartridge.  (See  Figure 2a or b.)
     7.4   Dewar flasks - 500 mL and 5 liter.
     7.5   Stopwatches.
     7.6   Various pressure  regulators and valves  - for connecting
           compressed gas cylinders to GC/MS system.
     7.7   Calibration gas  - In aluminum cylinder.  Prepared by
           user or vendor.   For GC/MS calibration.
     7.8   High pressure apparatus for preparing calibration gas
           cylinders (if conducted by user).  Alternatively, custom
           prepared gas mixtures can be purchased  from gas supply
           vendors.
     7.9   Friction top can  (e.g. one-gallon paint can) - With layer
           of activated charcoal to hold clean CMS cartridges.
     7.. 10  Thermometer - to  record ambient temperature.
     7.11  Barometer (optional).
     7.12  Dilution bottle - Two-liter with septum cap for standard
           preparation.
     7.13  Teflon stirbar -  1  inch long
     7.14  Gas tight syringes  -  10-500 u.1  for  standard injection  onto
           GC/MS system and  CMS  cartridges.
     7.15  Liquid microliter syringes - 5-50 ul for injecting neat
           liquid  standards into dilution bottle.
     7.16  Oven  -  60 +  5°C for equilibrating dilution bottle.

-------
                                T02-5
     7.17   Magnetic  stirrer.
     7.18   Variable  voltage  transformers  -  (120 V and  1000  VA)  and
           electrical  connectors  (or  temperature controllers) to
           heat  cartridge  and  cryogenic loop.
     7.19   Digital pyrometer - 30  to  500°C  range.
     7.20   Soap  bubble flow  meter  - 1, 10 and  100 mL calibration
           points.
     7.21   Copper  tubing  (1/8  inch) and fittings for gas inlet  lines.
     7.22   GC  column - SE-30 or alternative coating, glass capillary
           or  fused  silica.
     7.23   Psychrometer (optional).
     7.24   Filter  holder  - stainless  steel  or  aluminum (to accommodate
           1 inch  diameter filter).   Other  sizes may be used if
           desired,  (optional)

8.   Reagents  and Materials

     8.1   Empty CMS cartridges - Nickel  or stainless  steel  (See
           Figure 1).
     8.2   CMS Adsorbent, 60/80 mesh- Spherocarb®  from Analabs  Inc.,
           or  equivalent.
     8.3   Glasswool - silanized.
     8.4   Methylene chloride  - pesticide quality,  or  equivalent.
     8.5   Gas purifier cartridge for purge and  GC  carrier  gas
           containing  charcoal, molecular sieves,  and  a  drying
           agent.   Available from various chromatography supply
           houses.
     8.6   Helium -  Ultra pure, (99.9999%)  compressed  gas.
     8.7   Nitrogen  -  Ultra  pure, (99.9999%)  compressed  gas.
     8.8   Liquid nitrogen or  argon (50  liter dewar).
     8.9   Compressed  air, if  required -  for operation of GC  oven
           door.
     8.10  Perfluorotributyl amine (FC-43) for GC/MS calibration.
     8.11   Chemical  Standards  - Neat  compounds of  interest.   Highest
           purity available.

-------
                                 T02-6
9.   Cartridge Construction and Preparation

     9.1   A suitable cartridge design in shown in Figure 1.  Alternate
           designs have been reported (1) and are acceptable, provided
           the user documents their performance.  The design shown in
           Figure 1 has a built-in heater assembly.  Many users may
           choose to replace this heater design with a suitable
           separate heating block or oven to simplify the cartridge
           design.
     9.2   The cartridge is assembled as shown in Figure 1  using
           standard 0.25 inch O.D. tubing (stainless steel  or nickel),
           1/4 inch to 1/8 inch reducing unions, 1/8 inch nuts,
           ferrules, and endcaps.  These parts are rinsed with
           methylene chloride and heated at 250°C for 1 hour prior
           to assembly.
     9.3   The thermocouple bead is fixed to the cartridge body, and
           insulated with a layer of Teflon tape.  The heater wire
           (constructed from a length of thermocouple wire) is wound
           around the length of the cartridge and wrapped with Teflon
           tape to secure the wire in place.  The cartridge is then
           wrapped with woven silica fiber insulation (Zetex  or
           equivalent).  Finally the entire assembly is wrapped with
           fiber glass tape.
     9.4   After assembly one end of the cartridge is marked with
           a serial number to designate the cartridge inlet during
           sample collection.
     9.5   The cartridges are then packed with ^0.4 grams .of CMS
           adsorbent.  Glasswool plugs (MD.5 inches long) are placed
           at each end of the cartridge to hold the adsorbent firmly
           in place.  Care must be taken to insure that no strands
           of glasswool extend outside the tubing, thus causing
           leakage in the compression endfittings.  After loading the
           endfittings (reducing unions and end caps) are tightened
           onto the cartridge.

-------
                         T02-7
9.6   The cartridges are conditioned for initial  use by heating
      at 400°C overnight (at least 16 hours) with a 100 mL/minute
      purge of pure nitrogen.   Reused cartridges  need only to be
      heated for 4 hours and should be reanalyzed before use to
      ensure complete desorption of impurities.
9.7   For cartridge conditioning ultra-pure nitrogen gas is passed
      through a gas purifier to remove oxygen.moisture and organic
      contaminants.  The nitrogen supply is connected to the
      unmarked end of the cartridge and the flow  adjusted to
      ^50 mL/minute using a needle valve.  The gas flow from the
      inlet (marked) end of the cartridge is vented to the atmosphere.
9.8   The cartridge thermocouple lead is connected to a pyrometer
      and the heater lead is connected to a variable voltage
      transformer (Variac) set at 0 V_.  The voltage on the Variac
      is increased to ^15 _V and adjusted over a  3-4 minute period
      to stabilize the cartridge temperature at  380-400°C.
9.9   After 10-16 hours of heating (for new cartridges) the
      Variac is turned off and the cartridge is  allowed to cool
      to ^30°C, under continuing nitrogen flow.
9.10  The exit end of the cartridge is capped and then the entire
      cartridge is removed from the flow line and the other endcap
      immediately installed.  The cartridges are  then placed in  a
      metal friction top (paint) can containing ^2 inches of gran-
      ulated activated charcoal (to prevent contamination of the
      cartridges during storage) in the bottom, beneath a retaining
      screen.   Clean paper tissues (e.g. Kimwipes ) are placed in
      can to avoid damage to the cartridges during shipment.
9.11  Cartridges are stored in the metal can at all times except
      when in use.  Adhesives  initially present  in the cartridge
      insulating materials are "burnt off" during initial condition-
      ing.  Therefore, unconditioned cartridges should not be placed
      in the metal can since they may contaminate the other
      cartridges.
9.12  Cartridges are conditioned within two weeks of use.  A blank
      from each set of cartridges is analyzed prior to use in field

-------
                               T02-8
            sampling.   If an  acceptable  blank  level  is  achieved,  that
            batch of cartridges (including  the cartridge  serving  as  the
            blank) can be used for field sampling.
10.   Sampling
     10.1   Flow Rate and Total  Volume Selection
           10.1.1   Each compound has a  characteristic  retention
                    volume (liters of air per  unit weight of
                    adsorbent).   However, all  of the  compounds  listed
                    in Table  1  have retention  volumes (at 37°C)  in
                    excess of 100 liters/cartridge  (0.4 gram CMS
                    cartridge)  except vinyl  chloride  for  which  the
                    value is  ^30 liters/cartridge.   Consequently, if
                    vinyl chloride or similarly volatile  compounds are
                    of concern the maximum  allowable  sampling volume
                    is approximately 20  liters.  If  such  highly volatile
                    compounds are not of concern, samples as large as
                    100 liters can be collected.
           10.1.2   To calculate the maximum allowable  sampling flow
                    rate the  following equation can  be  used:
                         QMax =
           where
                    QM   is the calculated maximum sampling
                         rate in mL/minute.
                    t    is the desired sampling time in minutes.
                    Vu   is the maximum allowable total  volume
                     Max
                         based on the discussion in 10.1.1.
           10.1.3   For the cartridge design shown in Figure 1
                    should be between 20 and 500 mL/minute.   If
                    lies outside this range the sampling time or total
                    sampling volume must be adjusted so that this
                    criterion is achieved.

-------
                          T02-9
      10.1.4   The flow rate calculated in 10.1.3 defines the
               maximum allowable flow rate.   In general,  the
               user should collect additional  samples  in  parallel,
               at successive 2- to 4-fold lower flow rates.   This
               practice serves as a quality  control  procedure to
               check on component breakthrough and related sampling
               and adsorption problems, and  is further discussed
               in the literature (5).

10.2  Sample Collection

      10.2.1   Collection of an accurately known volume of air
               is critical to the accuracy of the results.   For
               this reason the use of mass flow controllers, rather
               than conventional  needle valves or orifices is highly
               recommended, especially at low flow rates  (e.g. less
               than 100 milliliters/minute).   Figure 2a illustrates
               a sampling system based on mass flow controllers
               which readily allows for collection of  parallel samples.
               Figure 2b shows a commercially available sampling system
               based on needle valve flow controllers.
      10.2.2   Prior to sample collection the sampling flow rate is
               calibrated near the value used for sampling,  with a
               "dummy" CMS cartridge in place.  Generally calibration
               is accomplished using a soap  bubble flow meter or
               calibrated wet test meter connected to  the flow exit,
               assuming the entire flow system is sealed.   ASTM
               Method D 3686 (4)  describes an appropriate calibration
               scheme, not requiring a sealed flow system downstream
               of the pump.
      10.2.3   The flow rate should be checked before  and after  each
               sample collection.   Ideally,  a rotemeter or mass  flow
               meter should be included in the sampling system to
               allow periodic observation of the flow  rate without
               disrupting the sampling process.

-------
                   T02-10

10.2.4   To collect an  air sample  the  cartridges  are removed
         from the sealed container just  prior  to  initiation  of
         the collection process.
10.2.5   The exit (unmarked)  end of the  cartridge  is  connected
         to the sampling apparatus.  The endcap is left on the
         sample inlet and the entire system is leak checked  by
         activating the sampling pump  and  observing  that no flow
         is  obtained  over a 1 minute period.   The sampling
         pump is then shut off.
10.2.6   The endcap is  removed from the  cartridge, a  particulate
         filter and holder are placed  on the inlet end  of  the
         cartridge, and the sampling pump  is started.   In  many
         situations a particulate  filter is not necessary  since
         the compounds  of interest are in  the  vapor  state.   How-
         ever, if,  large  amounts of  particulate matter are
         encountered, the filter may be  useful to  prevent  con-
         tamination of  the cartridge.  The following  parameters
         are recorded on an appropriate  data sheet  (Figure 4):
         date, sampling location,  time,  ambient temperature,
         barometric pressure, relative humidity,  dry gas meter
         reading (if applicable),  flow rate, rotometer  reading
         (if applicable), cartridge number, pump,  and dry  gas
         meter serial number.
10.2.7   The samples are collected for the desired time,
         periodically recording the variables  listed  above.  At
         the end of the sampling period  the parameters  listed
         in 10.2.6 are  recorded and the  flow rate  is  checked.
         If the flows at the beginning and end of  the sampling
         period differ  by more than 10%, the cartridge  should
         be marked as suspect.
10.2.8   The cartridges are removed (one at a  time),  the
         endcaps are replaced, and the cartridges  are placed
         into the original  container.  The friction  top can
         is sealed and  packaged for immediate  shipment  to  the
         analytical laboratory.

-------
                    T02-11

 10.2.9    The  average  sample  rate  is  calculated  and  recorded
          for  each  cartridge  according  to  the  following  equation:
where

          Q^  = Average  flow  rate  in ml/minute.
          Q-,, Qp,...Q.,  =  Flow  rates determined at
          beginning, end, and  immediate  points
          during sampling.

          N = Number of points averaged.

10-2.10   The total volumetric flow is obtained directly  from
          the dry gas meter  or calculated and recorded for
          each cartridge  using the following equation:

                 „  _Tx«A
where
                       TOOTT
         V  = Total volume sampled in liters at measured
              temperature and pressure.
         T  = Sampling time = T9-T,, minutes.
10.2.11  The total volume sampled (Vg) at standard conditions,
         760 mm Hg and 25°C, is calculated from the following
         equation:
                           Pa       298
                  's   'm x 760 x 273 + ta
V. = V.
where
                 Pa = Average barometric pressure, mm Hg
                 ta = Average ambient temperature, °C.

-------
                             T02-12

11.   Sample Analysis

     11.1   Sample Purging

           11.1.1  Prior to analysis  all  samples  are  purged  at room
                   temperature with pure, dry  air or  nitrogen  to remove
                   water vapor.   Purging  is  accomplished  as  described
                   in 9.7 except that the gas  flow is in  the same direction
                   as sample flow (i.e. marked end of cartridge is
                   connected to the flow  system).
           11.1.2  The sample is purged at 500 mL/minute  for 5 minutes.
                   After purging the  endcaps are  immediately replaced.
                   The cartridges are returned to the metal  can or
                   analyzed immediately.
          11:1.3   If very humid air  is being  sampled the purge time
                   may be increased to more  efficiently remove water
                   vapor.  However, the sum  of sample volume and purge
                   volume must be less than  75% of the retention  volume for
                   the most volatile  component of interest.

    11.2  GC/MS Setup

          11.2.1    Considerable variation from one laboratory  to another
                   is expected in terms of instrument configuration.
                   Therefore, each laboratory  must be responsible for
                   verifying that their particular system yields satis-
                   factory results.  Section 14 discusses specific
                   performance criteria which  should  be met.
          11.2.2   A block diagram of the analytical  system  required
                   for analysis  of CMS cartridges  is  depicted  in Figure 3.
                   The thermal  desorption system  must be  designed to
                   accommodate the particular  cartridge configuration.
                   For the CMS cartridge  design shown in  Figure 1, the
                   cartridge heating  is accomplished  as described in  9.8.
                   The use of a  desorption oven, in conjunction  with  a

-------
                     T02-13
        simplier cartridge design is also acceptable.   Exposure
        of the sample to metal  surfaces should be minimized and
        only stainless steel  or nickel  should be employed.
        The volume of tubing  leading from the cartridge to
        the GC column must be minimized and all  areas  must
        be well-swept by helium carrier gas.
11.2.3  The GC column oven must be capable of being cooled  to
        -70°C and subsequently temperature programmed  to 150°C.
11.2.4  The specific GC column and temperature program employed
        will be  dependent on  the compounds of interest.  Appro-
        priate conditions are described in the literature (2).
        In general, a nonpolar stationary phase  (e.g.  SE-30,
        OV-1) temperature programmed from -70 to 150°C at 8°/
        minute will be suitable.  Fused silica,  bonded-phase
        columns  are preferable to glass columns  since  they  are
        more rugged and can be inserted directly into  the MS
        ion source, thereby eliminating the need for a GC/MS
        transfer line.  Fused silica columns  are also  more
        readily  connected to  the GC injection valve (Figure 3).
        A drawback of fused silica, bonded-phase columns is the
        lower capacity compared to coated, glass capillary
        columns.  In most cases the column capacity will be less
        than 1 microgram injected for fused silica columns.
11.2.5  Capillary column dimensions of 0.3 mm ID and 50 meters
        long are generally appropriate although  shorter lengths
        may be sufficient in  many cases.
11.2.6  Prior to instrument calibration or sample analysis  the
        GC/MS system is assembled as shown in Figure 3.  Helium
        purge flow (through the cartridge) and carrier flow are
        set at approximately  50 mL/minute and 2-3 mL/minute
        respectively.  When a cartridge is not in place a union
        is placed in the helium purge line to ensure a continuous
        inert gas flow through the injection  loop.

-------
                           T02-14
      11.2.7   Once the column and other system components are assembled
               and the various flows established the column temperature
               is increased to 250°C for approximately four hours (or
               overnight if desired) to condition the column.
      11.2.8   The MS and data system are set up according to the
               manufacturer's instructions.  Electron impact ionization
               (70eV) and an electron multiplier gain of approximately
                     4
               5 x 10  should be employed.  Once the entire GC/MS
               system has been setup the system is calibrated as described
               in Section 11.3.  The user should prepare a detailed
               standard operating procedure (SOP) describing this process
               for the particular instrument being used.
11.3  GC/MS Calibration
      11.3.1    Tuning and mass  standardization  of  the MS  system is  per-
               formed according to  manufacturer's  instructions
               and relevant  user prepared  SOPs.  Perfluorotributyl amine
               (FC-43) should  generally be employed  as  the  reference
               compound.   The  material  is  introduced directly  into  the
               ion source through a molecular  leak.  The  instrumental
               parameters (e.g., lens  voltages,  resolution,  etc.)
               should be  adjusted to give  the  relative  ion  abundances
               shown in Table  2, as well as acceptable  resolution and
               peak shape.   If these approximate relative abundances
               cannot be  achieved,  the ion source  may require  cleaning
               according  to  manufacturer's instructions.  In the event
               that the user's  instrument  cannot achieve  these  relative
               ion abundances,  but  is  otherwise operating properly,
               the user may  adopt another  set  of relative abundances
               as performance  criteria. However,  these alternate
               values must be  repeatable on a  day-to-day  basis.

-------
                   T02-15

11.3.2   After the mass standardization and tuning process has
         been completed and the appropriate values entered into
         the data system, the user should then calibrate the
         entire GC/MS system by introducing known quantities
         of the components of interest into the system.   Three
         alternate procedures may be employed for the calibra-
         tion process including 1) direct injection of dilute
         vapor phase standards, prepared in a dilution bottle
         or compressed gas cylinder, onto the GC column,
         2) injection of dilute vapor phase standards into a
         flowing inert gas stream directed onto a CMS cartridge,
         and 3) introduction of permeation or diffusion  tube
         standards onto a CMS cartridge.  Direct injection of a
         compressed gas cylinder (aluminum) standard containing
         trace levels of the compounds of interest has been found
         to be the most convenient practice since such standards
         are stable over a several month period.   The standards
         preparation processes for the various approaches  are
         described in Section 13.   The following paragraphs
         describe the instrument calibration process for these
         approaches.
11.3.3   If the system is to be calibrated by direct injection
         of a vapor phase standard, the standard, in either a
         compressed gas cylinder or dilution flask,  is obtained
         as described in Section 13.   The MS and  data system
         are setup for acquisition, but the ionizer filament
         is shut off.  The GC column oven is cooled to -70°C,
         the injection valve is placed in the load mode, and the
         cryogenic loop is immersed in liquid nitrogen or  liquid
         argon.   Liquid argon is required for standards  prepared
         in nitrogen or air, but not for standards prepared in
         helium.   A known volume of the standard  (10-1000  ml)
         is injected through the cryogenic loop at a rate  of
         10-100 mL/minute.

-------
                   T02-16

11.3.4   Immediately after  loading  the  vapor  phase  standard,  the
         injection valve  is placed  in the  inject mode,  the  GC
         program and system clock are started,  and  the  cryogenic
         loop is heated to  60°C  by  applying voltage (15-20  volts)
         to the thermocouple wire heater surrounding  the  loop.
         The voltage is adjusted to maintain  a  loop temperature
         of 60°C.   An automatic  temperature controller  can  be
         used in place of the manual control  system.  After
         elution of unretained components  (<3 minutes after
         injection) the ionizer  filament is turned  on and data
         acquisition is initiated.   The helium  purge  line (set
         at 50 mL/minute) is connected  to  the injection valve
         and the valve is returned  to the  load  mode.  The loop
         temperature is increased to 150°C, with helium purge,
         and held at this temperature until the next  sample is
         to be loaded.
11.3.5   After the last component of interest has eluted,
         acquisition is terminated  and  the data is  processed  as
         described in Section 11.3.8.   The standard injection
         process is repeated using  different  standard concentra-
         tions and/or volumes to cover  the analytical range of
         interest.
11.3.6   If  the system is  to be calibrated by  analysis of
         standard CMS cartridges, a series of cartridges  is
         prepared as described in Sections 13.2 or  13.3.  Prior
         to analysis the  cartridges are stored  (no  longer than
         48 hours) as described  in  Section 9.10.  For analysis
         the injection valve is  placed  in  the load  mode and the
         cryogenic loop is  immersed in  liquid nitrogen  (or
         liquid argon if  desired).   The CMS cartridge is  installed
         in the helium purge line  (set  at  50  mL/minute) so  that
         the helium flow  through the cartridge  is opposite  to
         the direction of sample flow and  the purge gas is
         directed through the cryogenic loop  and vented to  the

-------
                         T02-17

               atmosphere.   The CMS cartridge is heated to 370-400°C
               and maintained at this temperature for 10 minutes (using
               the temperature control  process described in Section 9.8).
               During  the  desorption period, the GC column oven is
               cooled to -70°C and the MS and data system are setup for
               acquisition, but the ionizer filament is turned off.
      11.3.7   At the end of the 10 minute desorption period, the ana-
               lytical process described in Sections 11.3.4 and 11.3.5
               is conducted.  During the GC/MS analysis heating of the
               CMS cartridge is discontinued.  Helium flow is maintained
               through the  CMS cartridge and cryogenic loop until  the
               cartridge has cooled to room temperature.  At that time,
               the cryogenic loop is allowed to cool to room temperature
               and the system is ready for further cartridge analysis.
               Helium flow  is maintained through the cryogenic loop at
               all times, except during the installation or removal of
               a CMS cartridge, to minimize contamination of the loop.
      11.3.8   Data processing for instrument calibration involves
               determining  retention times, and integrated characteristic
               ion intensities for each of the compounds of interest.
               In addition, for at least one chromatographic run,  the
               individual mass spectra should be inspected and compared
               to reference spectra to ensure proper instrumental
               performance.  Since the steps involved in data processing
               are highly instrument specific,.the user should prepare
               a SOP describing the process for individual  use.   Overall
               performance  criteria for instrument calibration are
               provided in  Section 14.   If these criteria are not
               achieved, the user should refine the instrumental
               parameters and/or operating procedures to meet these
               criteria.

11.4  Sample Analysis

      11.4.1   The sample analysis is identical to that described
               in Sections  11.3.6 and 11.3.7 for the analysis of
               standard CMS cartridges.

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                             T02-18

           11.4.2  Data processing for  sample  data  generally  involves
                   1)  qualitatively determining  the presence  or  absence
                   of  each component of interest on the  basis  of a  set
                   of  characteristic ions  and  the retention time using
                   a reversed-search software  routine, 2)  quantification
                   of  each identified component  by  integrating the  intensity
                   of  a characteristic  ion and comparing the  value  to
                   that of the calibration standard,  and 3) tentative
                   identification  of other components observed using a
                   forward (library) search  software  routine.  As for
                   other user specific  processes, a SOP  should be prepared
                   describing the  specific operations for  each individual
                   laboratory.

12.   Calculations

     12.1   Calibration Response Factors
           12.1.1  Data from calibration standards  is used to  calculate a
                   response factor for  each  component of interest.
                   Ideally the process  involves  analysis of at least three
                   calibration levels of each  component  during a given
                   day and determination of the  response factor  (area/
                   nanogram injected) from the linear least squares
                   fit of a plot of nanograms  injected versus  area
                   (for the characteristic ion).  In  general,  quantities
                   of  components greater than  1,000 nanograms  should not
                   be  injected because  of  column overloading  and/or MS
                   response nonlinearity.
           12.1.2  In  practice the daily routine may  not always  allow
                   analysis of three such  calibration standards.  In
                   this situation  calibration  data  from  consecutive days
                   may be pooled to yield  a  response  factor,  provided
                   that analysis of replicate  standards  of the same
                   concentration are shown to  agree within 20% on the
                   consecutive days. In all cases  one given  standard

-------
                       T02-19

             concentration, near the midpoint of the analytical
             range of interest, should be injected at least once
             each day to determine day-to-day precision of response
             factors.

     12.1.3  Since substantial nonlinearity may be present in the
             calibration curve, a nonlinear least squares fit
             (e.g. quadratic) should be employed.  This process
             involves fitting the data to the following equation:
                        Y = A + BX + CX2
     where
             Y = peak area
             X = quantity of component injected nanograms
             A, B, and C are coefficients in the equation.
12.2  Analyte Concentrations

      12.2.1   Analyte quantities  on  a  sample  cartridge  are  calculated
              from the following  equation:

                         YA =  A + BXA  + CX2

      where   Y.  is the area of the  analyte characteristic  ion  for
                the sample cartridge.
              X/\ is the calculated quantity of  analyte  on the sample
                cartridge, in  nanograms.
              A,  B, and C are  the coefficients  calculated from  the
                calibration curve described in  Section  12.1.3.
      12.2.2   If instrumental  response is  essentially linear over the
              concentration range of interest,  a  linear equation
              (C=0 in the equation above)  can be  employed.

-------
                             T02-20

           12.2.3  Concentration  of  analyte  in  the original  air  sample
                   is  calculated  from the  following  equation:
                           C  =XA
                           CA
           where
                   C.  is the calculated  concentration  of  analyte  in  ng/L.

                   Vs and X. are as  previously  defined in Section 10.2.11
                   and 12.2.1,  respectively.
13.   Standard Preparation

     13.1   Standards for Direct Injection

           13.1.1   Standards for direct injection  can  be  prepared in
                   compressed gas cylinders  or in  dilution  vessels.
                   The dilution flask protocol has been described in
                   detail in another method  and is not repeated here (6).
                   For the CMS method where  only volatile compounds
                   (boiling point <120°C)  are of concern, the preparation
                   of dilute standards in  15 liter aluminum compressed
                   gas cylinders has been  found to be  most  convenient.
                   These standards are generally stable over at least a
                   3-4 month period and in some cases  can be purchased
                   from commercial suppliers on a  custom  prepared basis.
           13.1.2  Preparation of compressed gas cylinders  requires
                   working with high pressure tubing and  fittings, thus
                   requiring a user prepared SOP which ensures that
                   adequate safety precautions are taken.  Basically,
                   the preparation process involves injecting a pre-
                   determined amount of neat liquid or gas  into an
                   empty high pressure cylinder of known  volume, using
                   gas flow into the cylinder to complete the transfer.

-------
                              T02-21

                    The cylinder is then pressurized to a given value
                    (500-1000 psi).  The final cylinder pressure must be
                    determined using a high precision gauge after the
                    cylinder has thermally equilibrated for a 1-2 hour
                    period after filling.
            13.1.2  The concentration of components in the cylinder
                    standard should be determined by comparison with
                    National Bureau of Standards reference standards
                    (e.g. SRM 1805-benzene in nitrogen) when available.
            13.1.3  The theoretical concentration (at 25°C and 760 mm
                    pressure) for preparation of cylinder standards
                    can be calculated using the following equation:

                              CT = VI x d   14.7      x 24.4 x 1000
                                   Vc     x Pc + 14>7
            where   CT  is the component concentration, in ng/mL at 25°C
                        and 760 mm Hg pressure.
                    Vj  is the volume of neat liquid component injected,
                        in yL.
                    Vc  is the internal volume of the cylinder,  in  L.
                    d   is the density of the neat liquid component,
                        in g/mL.
                    PC  is the final pressure of the cylinder standards,
                        in pounds per square inch gauge (psig).

13.2   Preparation of  Spiked  Traps  by Vapor Phase  Injection

       This process involves  preparation  of a  dilution  flask
       or compressed gas cylinder containing the desired concentra-
       tions of the compound(s)  of  interest and  injecting  the desired
       volume of vapor into  a  flowing gas  stream which  is  directed
       onto a clean CMS cartridge.   The procedure  is  described  in
       detail  in another method  within the  Compendium (6)  and will  not  be
       repeated here.

-------
                            T02-22

    13.3  Preparation of Spiked Traps Using Permeation or Diffusion Tubes

          13.3.1  A flowing stream of inert gas containing known amounts
                  of each compound of interest is generated according
                  to ASTM Method D3609 (4).  Note that a method of
                  accurately maintaining temperature within +_ 0.1°C is
                  required and the system generally must be equilibrated
                  for at least 48 hours before use.
          13.3.2  An accurately known volume of the standard gas stream
                  (usually 0.1-1 liter) is drawn through a clean CMS
                  cartridge using the sampling system described in
                  Section 10.2.1, or a similar system.  However, if mass
                  flow controllers are employed, they must be calibrated
                  for the carrier gas used in Section 13.3.1 (usually
                  nitrogen).  Use of air as the carrier gas for permeation
                  systems is not recommended, unless the compounds of
                  interest are known to be highly stable in air.
          13.3.3  The spiked traps are then stored or immediately
                  analyzed as in Sections 11.3.6 and 11.3.7.


14.  Performance Criteria and  Quality Assurance

     This section summarizes  the  quality  assurance  (QA)  measures  and
     provides guidance  concerning performance  criteria which  should be
     achieved within each laboratory.   In many cases  the specific QA
     procedures have been described  within the appropriate  section
     describing the  particular activity (e.g.  parallel sampling).

     14.1  Standard  Operating  Procedures  (SOPs)

           14.1.1  Each user should  generate  SOPs describing  the  following
                   activities  as  accomplished  in their laboratory:
                   1) assembly,  calibration and  operation of the  sampling
                   system, 2)  preparation, handling and  storage of CMS
                   cartridges, 3) assembly and operation of GC/MS system
                   including the thermal  desorption apparatus and data
                   system, and 4) all aspects  of data recording and processing

-------
                        T02-23

      14.1.2  SOPs should provide specific stepwise instructions and
              should be readily available to, and understood by the
              laboratory personnel  conducting the work.

14.2  CMS Cartridge Preparation

      14.2.1  Each batch of CMS cartridges,  prepared  as described  in
              Section 9, should be  checked for contamination by
              analyzing one cartridge, immediately after  preparation.
              While analysis can be accomplished by GC/MS,  many
              laboratories may chose to use GC/FID due to logistical
              and cost considerations.
      14.2.2  Analysis by GC/FID is accomplished as described for
              GC/MS (Section 11) except for use of FID detection.
      14.2.3  While acceptance criteria can vary depending  on the
              components of interest, at a minimum the clean
              cartridge should be demonstrated to contain less than
              one-fourth of the minimum level of interest for each
              component.  For most  compounds the blank level should
              be less than 10 nanograms per cartridge in  order to  be
              acceptable.   More rigid criteria may be adopted, if
              necessary, within a specific laboratory. If  a cartridge
              does not meet these acceptance criteria, the  entire  lot
              should be rejected.

14.3  Sample Collection

      14.3.1  During each sampling  event at least one clean cartridge
              will accompany the samples to the field and back to  the
              laboratory,  having been placed in the sampler but  without
              sampling air, to serve as a field blank. The average
              amount of material found on the field blank cartridges
              may be subtracted from the amount found on  the actual
              samples.   However, if the blank level is greater than

-------
                       T02-24

             25% of the sample amount, data for that component
             must be identified as suspect.
     14.3.2  During each sampling event at least one set of
             parallel samples (two or more samples collected
             simultaneously) should be collected, preferably at
             different flow rates as described in Section 10.1.4.
             If agreement between parallel samples is not generally
             within +25% the user should collect parallel samples
             on a much more frequent basis (perhaps for all sampling
             points).  If a trend of lower apparent concentrations
             with increasing flow rate is observed for a set of
             parallel samples one should consider usi/ig a reduced
             sampling rate and longer sampling interval, if possible.
             If this practice does not improve the  reproducibility
             further evaluation of the method performance for the
             compound of interest might be required.
     14.3.3  Backup cartridges (two cartridges in series) should be
             collected with each sampling event.  Backup cartridges
             should contain less than 10% of the amount of components
             of interest found in the front cartridges, or be equiva-
             lent to the blank cartridge level, whichever is greater.

14.4  GC/MS Analysis

      14.4.1   Performance  criteria  for MS  tuning  and  mass  standardiza-
              tion have been discussed in  Section 11.2  and Table  2.
              Additional  criteria can  be  used  by  the  laboratory,
              if desired.   The following  sections provide performance
              guidance and suggested criteria  for determining the
              acceptability of the GC/MS  system.

-------
                  T02-25

14.4.2  Chromatographic efficiency should be evaluated daily
        by the injection of calibration standards.   A reference
        compound(s) should be chosen from the calibration
        standard and plotted on an expanded time scale so that
        its width at 10% of the peak height can be  calculated,
        as shown in Figure 6.  The width of the peak at 10%
        height should not exceed 10 seconds.  More  stringent
        criteria may be required for certain applications.
        The asymmetry factor (see  Figure 6) should  be between
        0.8 and 2.0.  The user should also evaluate chroma-
        tographic performance for any polar or reactive compounds
        of interest, using the process described above.  If peaks
        are observed that exceed the peak width or  asymmetry
        factor criteria above, one should inspect the  entire
        system to determine if unswept zones or cold spots  are
        present in any of the fittings or tubing and/or if
        replacement of the GC column is required.  Some labora-
        tories may chose to evaluate column performance separately
        by direct injection of a test mixture onto  the GC
        column.  Suitable schemes for column evaluation have been
        reported in the literature (7).
14.4.3  The detection limit for each component is calculated
        from the data obtained for calibration standards.   The
        detection limit is defined as
                     DL = A + 3.3S
where
        DL is the calculated detection limit in nanograms
           injected.
        A is the intercept calculated in Section 12.1.3.
        S is the standard deviation of replicate determina-
           tions of the lowest level standard (at least three
           such determinations are required).   The lowest

-------
                       T02-26

              level standard should yield a signal to noise ratio
              (from the total ion current response) of approximately 5.
      14.4.4   The  relative standard deviation for replicate analyses
              of cartridges spiked at approximately 10 times the
              detection limit should be 20% or less.  Day to day
              relative standard deviation for replicate cartridges
              should be 25% or less.
      14.4.5   A useful performance evaluation step is the use of an
              internal standard to track system performance.  This
              is accomplished by spiking each cartridge, including
              blank, sample, and calibration cartridges with approx-
              imately 100 nanograms of a compound not generally
              present is ambient air (e.g. perfluorotoluene).  Spik-
              ing  is readily accomplished using the procedure outlined
              in Section 13.2, using a compressed gas standard.  The
              integrated ion intensity for this compound helps to
              identify problems with a specific sample.  In general
              the  user should calculate the standard deviation of the
              internal standard response for a given set of samples
              analyzed under identical tuning and calibration conditions,
              Any  sample giving a value greater than +_ 2 standard
              deviations from the mean (calculated excluding that
              particular sample) should be identified as suspect.
              Any  marked change in internal standard response may
              indicate a need for instrument recalibration.

14.5  Method  Precision and Recovery

      14.5.1   Recovery and precision data for selected volatile organic
              compounds are  presented  in Table 1.  These data were
              obtained using ambient air, spiked with known amounts
              of  the  compounds  in a dynamic mixing  system  (2).
      14.5.2   The  data in Table 1 indicate that in  general  recoveries
              better  than 75% and precision  (relative standard
              deviations) of 15-20% can be obtained.  However,
              selected compounds  (e.g. carbon tetrachloride and

-------
          T02-27

benzene) will have poorer precision and/or recovery.
The user must check recovery and precision for any
compounds for which quantitative data are  needed.

-------
                               T02-28


                           References
1.  Kebbekus, B.  B.  and J.  W.  Bozzelli.   Collection and Analysis  of
    Selected Volatile Organic  Compounds  in Ambient Air.  Proceedings
    of Air Pollution Control Association, Paper No. 82-65.2,  Air
    Pollution Control Association,  Pittsburgh,  Pennsylvania,  1982.

2.  Riggin R. M.  and L. E.  Slivon.   Determination of Volatile Organic
    Compounds in  Ambient Air Using  Carbon Molecular Sieve Adsorbants,
    Special Report on Contract 68-02-3745 (WA-7), U.S.  Environmental
    Protection Agency, Research Triangle Park,  North Carolina, September,
    1983.

3.  Riggin, R. M., "Technical  Assistance Document for Sampling and
    Analysis of Toxic Organic  Compounds  in Ambient Air",  EPA-600/4-
    83-027, U.S.  Environmental Protection Agency, Research Triangle
    Park, North Carolina, 1983.

4.  Annual Book of ASTM Standards,  Part  11.03,  "Atmospheric Analysis:
    Occupational  Health and Safety", American Society for Testing and
    Materials, 1983.

5.  Walling, J. F., Berkley, R. E., Swanson,  D. H., and Toth, F.  J.
    "Sampling Air for Gaseous  Organic Chemical-Applications to Tenax",
    EPA-600/7-54-82-059, U.S.  Environmental Protection Agency, Research
    Triangle Park, North Carolina,  1982.

6.  This Methods  Compendium -  Tenax Method (TO 1).

7.  Grob, K., Jr., Grob, G., and Grob, K., "Comprehensive Standardized
    Quality Test for Glass  Capillary Columns",  J. Chromatog., 156
    1-20, 1978.

-------
                           TABLE 1.   VOLATILE ORGANIC COMPOUNDS FOR WHICH THE
                                     CMS ADSORPTION METHOD HAS BEEN EVALUATED
Compound
Vinyl Chloride
Acrylonitrile
Vinylidene Chloride
Methylene Chloride
Ally! Chloride
Chloroform
1 ,2-Dichloroethane
1 ,1 ,1-Trichloroethane
Benzene
Carbon Tetrachloride
Tol uene
Retention
Time,/ x
6.3
10.8
10.9
11.3
11.4
13.8
14.5
14.7
15.4
15.5
18.0
Characteristic
Mass Fragment
Used For
Quantification
62
53
96
84
76
83
62
97
78
117
91
Method Performance -Data^ '
Concentration,
ng/L
17
20
36
28
32
89
37
100
15
86
4.1
Percent
Recovery
74
85
94
93
72
91
85
75
140
55
98
Standard
Deviation
19
18
19
16
19
12
11
9.1
37
2.9
5.4
a)  GC conditions as follows:

        Column - Hewlett Packard, crosslinked methyl silicone,
                 0.32 mm ID x 50 mm long, thick film, fused silica.

                 Temperature Program - 70°C for 2 minutes then increased at
                                        8°C/minute to 120°C.

b)  From Reference 2.  For spiked ambient air.
                                                                                                             o
                                                                                                             ro
                                                                                                             ro

-------
                       T02-30
TABLE 2.  SUGGESTED PERFORMANCE CRITERIA FOR RELATIVE
          ION ABUNDANCES FROM FC-43 MASS CALIBRATION
M/E
51
69
100
119
131
169
219
264
314
% Relative
Abundance
1.8 +0.5
100
12.0 + 1.5
12.0 + 1.5
35.0 + 3.5
3.0 + 0.4
24.0 + 2.5
3.7 + 0.4
0.25 + 0.1

-------
                   T02-31
                                  Thormocoupte
                          Zetex
                          Insulation
                         /- Fiberglass
                        / Tape
           nnnun
            1/4" Nut
                                       Thermocouple
                                       Connector
                Heater
                Connector
          Reducing
          Union
• Stainless
Steel Tube
1/4" O.D. x 3" Long
FIGURE 1.  DIAGRAM SHOWING CARBON MOLECULAR SIEVE TRAP (CMS) CONSTRUCTION

-------
                                             T02-32
                                                             Coupling*
                                                             to Connect
                                                             CMS
                                                             Cartridges
                      Vent
                                          Man Flow
                                          Controllers
                                      (a)  Mass Flow Control
                        Rotomttar
Vent


Dry
Test
Meter








^m



mm




rfri
1 — V
Needle
Valve









Pump





1 Connect CMS


                                     (b) Needle Valve Control
                  FIGURE 2.   TYPICAL SAMPLING  SYSTEM  CONFIGURATIONS

-------
                                       T02-33
              Couplings for
              CMS Cartridge
                                       Vent
                                             Heated 6-Port
                                             Injection Valve

                                            .	• Cryogenic Loop (•*• Figure S)
Helium Twik
and Regulator
   Flow
   Control!*™'
           Liquid Nitrogen '
                HwHifn Purge
                From Cooling H
OC Column
  Own
                                       GC Column
                                     Cooling to -70 C

                                  (b) Vaivt-Load Mod*
                                         V*m
                                       OC Column

                                  («) Vilve- Intact Mod*
                    Spectrometer
                                                          Cryogenic Trap
                                                          Held at Liquid N2
                                                          Temperature
                                                             Helium Carrier
                                                             Flow — 2-3 ml/minut*
                      Cryogenic Trap
                      HaMateoC
   FIGURE  3.   GC/MS  ANALYSIS SYSTEM  FOR CMS  CARTRIDGES

-------
                                          T02-3**
                                SAMPLING DATA SHEET
                            (One Sample Per Data Sheet)
PROJECT:_

SITE:
    DATE(S) SAMPLED:
LOCATION:
    TIME PERIOD SAMPLED:

    OPERATOR:
INSTRUMENT MODEL NO:.

PUMP SERIAL NO:	

SAMPLING DATA
    CALIBRATED BY:
                        Sample  Number:_

                 Start Time:
     Stop Time:
Time
1.
2.
3.
4.
N.
Dry Gas
Meter
Reading





Rotameter
Reading





Flow
Rate,*Q
ml/Min





Ambient
Temperature
°C





Barometric
Pressure,
mmHg





Relative
Humidity, %





Comments





   Total Volume Data**
           Vm = (Final  - Initial)  Dry Gas Meter Reading,  or
                    + 0.2 + 0.3...QN
1
                                     1000 x (Sampling Time in Minutes)
Liters

Liters
     * Flowrate from rotameter or soap bubble calibrator
       (specify which).
    ** Use  data from dry gas meter if available.
                      FIGURE 4.  EXAMPLE SAMPLING DATA SHEET

-------
                  T02-35
oc
Oo
oo
DO
OCj
           1/8" to 1/16" Reducing Union
           1/8" Swageiok Nut and Ferrule
Silanized

  Glass

  Wool

1/2" Long
          60/80 Mesh Silanized Glass Beads.
        Stainless Steel

        Tubing

        1/8" O.D. x 0.08" I.D. x 8" Long
oo
30
OC

JDC
30
                                          OO
                                           >o

                                           °0
                                           00
     FIGURE 5.   CRYOGENIC  TRAP DESIGN

-------
             T02-36
                          BC
         Asymmetry Factor • -?-=•
                          AB
Example Calculation:
     Paak Height - DE - 100 mm
     10% Peak Height - BD • 10 mm
     Peak Width at 10% Peak Height - AC - 23 mm
         AB - 11 mm
         BC *12mm
     Therefore: Asymmetry Factor - —
1.1
FIGURE 6. PEAK ASYMMETRY CALCULATION

-------
                                METHOD T03                Revision  1.0
                                                          April,  1984
       METHOD FOR THE DETERMINATION OF VOLATILE ORGANIC COMPOUNDS
       IN AMBIENT AIR USING CRYOGENIC PRECONCENTRATION TECHNIQUES
            AND GAS CHROMATOGRAPHY WITH FLAME IONIZATION AND
                     AND ELECTRON CAPTURE DETECTION
1.     Scope

      1.1   This document describes a method for the determination of
            highly volatile compounds having boiling points in the range
            of -10 to 200°C.
      1.2   The methodology detailed in this document is currently
            employed by numerous laboratories (l-4;8-ll).   Modifications
            to this methodology should be accompanied by appropriate
            documentation of the validity and reliability of these
            changes.

2.     Applicable Documents

      2.1   ASTM Standards

            D1356 Definition of Terms Related to Atmospheric Sampling
            and Analysis
            E 355 Recommended Practice for Gas Chromatography Terms
            and Relationships

      2.2   Other Documents

            Ambient Air Studies (1-4).
            U. S. EPA Technical Assistance Document (5).

3.     Summary of Method

      3.1   Ambient air analyses are performed as follows.   A collection
            trap, as illustrated in Figure 1, is submerged  in either
            liquid oxygen or argon.  Liquid argon is highly recommended
            for use because of the safety hazard associated with liquid

-------
                                T03-2
            oxygen.   With the sampling valve  in  the  fill  position  an
            air sample is then admitted into  the trap  by  a  volume
            measuring apparatus.   In the meantime, the column  oven is
            cooled to a sub-ambient temperature  (-50°C).  Once sample
            collection is completed, the valve is switched  so  that the
            carrier gas sweeps the contents of the trap onto the head of
            the cooled GC column.   Simultaneously, the liquid  cryogen is
            removed and the trap  is heated to assist the  sample transfer
            process.   The GC column is temperature programmed  and  the
            component peaks eluting from the  columns are  identified and
            quantified using flame ionization and/or electron  capture
            detection.  Alternate  detectors  (e.g. photoionization) can  be
            used as appropriate.   An automated system  incorporating
            these various operations as well  as  the  data  processing
            function has been described in the literature (8,9).
      3.2   Due to the complexity  of ambient  air samples, high resolution
            (capillary column) GC  techniques  are recommended.   However,
            when highly selective  detectors  (such as the  electron
            capture detector) are  employed, packed column technology
            without cryogenic temperature programming  can be effectively
            utilized in some cases.

4.    Significance

      4.1   Volatile organic compounds are emitted into the atmosphere
            from a variety of sources including  industrial  and commercial
            facilities, hazardous  waste storage  facilities, etc.  Many
            of these compounds are toxic, hence  knowledge of the levels
            of such materials in  the ambient  atmosphere is  required in
            order to determine human health  impacts.
      4.2   Because these organic  species are present at  ppb levels or
            below, some means of  sample preconcentration  is necessary in
            order to acquire sufficient material for identification and
            quantitation.  The two primary preconcentration techniques
            are cryogenic collection and the  use of  solid adsorbents.
            The method described  herein involves the former technique.

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                               T03-3

5.    Definitions

      Definitions used in this document and any user prepared SOPs should
      be consistent with ASTM Dl356 (6).  All abbreviations and symbols
      are defined within this document at the point of use.

6.    Interferences/Limitations

      6.1   Compounds having similar GC retention times will interfere
            in the method.  Replacing the flame ionization detector
            with more selective detection systems will  help to minimize
            these interferences.  Chlorinated species,  in particular,
            should be determined using the electron capture detector
            to avoid interference from volatile hydrocarbons.
      6.2   An important limitation of the technique is the condensation
            of moisture in the collection trap.   The possibility of
            ice plugging the trap and  stopping the flow is of  concern,
            and water subsequently transferred to the capillary column
            may also result in flow stoppage and cause  deleterious effects
            to certain column materials.   Use of permaselective Nafion®
            tubing in-line before the  cryogenic  trap avoids this problem;
            however, the material  must be used with caution because of
            possible loses of certain  compounds.  Another potential
            problem is contamination from the Nafion ®  tubing.   The
            user should consult the literature (7-12) for details  on the
            use of permeation-type driers.

7.    Apparatus

      7.1   Gas chromatograph/Flame lonization/Electron Capture
            Detection System- must be  capable of subambient temperature
            programming.   A recent publication (8) describes an automated
            GC system in  which the cyrogenic sampling and analysis
            features are  combined.   This  system  allows  simultaneous
            flame ionization and electron  capture  detection.

-------
                                T03-4
      7.2   Six-port sampling  valve  -  modified  to  accept  a  sample
            collection  trap  (Figure  1).
      7.3   Collection  trap  -  20  cm  x  0.2  cm  I.D.  stainless  steel
            tubing packed  with 60/80 mesh  silanized  glass beads  and  sealed
            with  glass  wool.   For the  manual  system  (Section  9.2)  the
            trap  is externally wrapped with 28  gauge (duplex  and
            fiberglass  insulated) type "K" thermocouple wire.  This
            wire,  beaded at  one end, is  connected  to a powerstat
            during the  heating cycle.  A thermocouple is  also attached
            to the trap as shown  in  Figure 1.
      7.4   Powerstat - for  heating  trap.
      7.5   Temperature readout device - for  measuring trap  temperature
            during heating cycle.
      7.6   Glass  dewar flask  - for  holding cryogen.
      7.7   Sample volume  measuring  apparatus - capable of  accurately
            and precisely  measuring  a  total sample volume up  to  500  cc
            at sampling rates  between  10 and  200 cc/minute.   See Section  9.
      7.8   Stopwatch.
      7.9   Dilution container for standards  preparation  -  glass flasks
            or Teflon (Tedlar) bags, .002  inch  film  thickness (see
            Figure 2).
      7.10  Liquid microliter  syringes - 5-50 yl for injecting liquid
            standards into dilution  container.
      7.11  Volumetric  flasks  - various  sizes,  1-10  ml.
      7.12  GC column - Hewlett Packard  50 meter methyl silicone cross-
            linked fused silica column (.3 mm I.D.,  thick film)  or
            equivalent.
      7.13  Mass  flow controller  - 10-200  mL/minute  flow  control range.
      7.14  Permeation  drier - PermaPure® -  Model MD-125F,  or equivalent.
            Alternate designs  described  in the  literature (7-12) may also
            be acceptable.

8.    Reagents and Materials

      8.1   Glass beads -  60/80 mesh,  silanized.

-------
                                T03-5
      8.2   Glasswool  -  silanized.
      8.3   Helium -  zero grade compressed  gas,  99.9999%.
      8.4   Hydrogen  - zero grade  compressed  gas,  99.9999%.
      8.5   Air -  zero grade compressed  gas.
      8.6   Liquid argon (or liquid  oxygen).
      8.7   Liquid nitrogen.
      8.8   SRM 1805  - benzene  in  nitrogen  standard.  Available  from  the
            National  Bureau of  Standards.   Additional such standards  will
            become available in the  future.
      8.9   Chemical  standards  - neat compounds  of  interest, highest
            purity available.

9.     Sampling and Analysis Apparatus

      Two systems  are described below which allow collection of  an
      accurately known volume of air (100-1000 ml)  onto a  cryogenically
      cooled trap.  The  first system (Section 9.1)  is an automated
      device described in the literature (8,9).   The  second system
      (Section 9.2) is a manual device,  also  described  in  the  liter-
      ature (2).

      9.1   The automated sampling and analysis  system  is  shown  in  Figure
            3.  This  system is  composed  of  an automated GC system
            (Hewlett  Packard Model  5880A, Level  4,  or equivalent) and a
            sample collection system (Nutech  Model  320-01, or  equivalent).
            The overall  system  is  described in the  literature  (8).

            9.1.1   The  electronic console  of the  sampling unit  controls
                    the  mechanical  operation  of  the six-port valve  and
                    cryogenic trapping components  as well  as the tempera-
                   tures in each  of the three zones  (sample trap,  transfer
                    line, and valve).

-------
                          T03-6
      9.1,2   The valve (six-port air activated,  Seiscor Model  8
              or equivalent) and transfer line are constantly
              maintained at 120°C.   During sample collection the
              trap temperature is maintained at -160 + 5°C by
              a flow of liquid nitrogen  controlled by a solenoid
              valve.   A cylindrical  250  with heater, held in
              direct contact with the trap,  is used to heat the
              trap to 120°C in 60 seconds or less during the sample
              desorption step.  The  construction  of the sample
              trap is described in Section 7.3.
      9.1.3   The sample flow is controlled  by a  pump/mass flow
              controller assembly, as shown  in Figure 3.   A sample
              flow of 10-100 mL/minute is generally employed,
              depending on  the desired sampling period.   A total
              volume  of 100-1000 ml  is commonly collected.
      9.1.4   In many situations a permaselective drier (e.g.
              Nafion®)  may  be required to remove  moisture from
              the sample.   Such a device is  installed at the sample
              inlet.   Two configurations for such devices are
              available. The first  configuration is the tube  and
              shell  type in which the sample flow tube is surrounded
              by an outer shell through  which a countercurrent  flow
              of clean, dry air is maintained. The dry air stream
              must be free  from contaminants and  its flow rate  should
              be 3-4 times  greater than  the  sample flow to achieve
              effective drying.  A second configuration (7)
              involves  placing a drying  agent, e.g.  magnesium
              carbonate, on the outside  of the sample flow tube.
              This approach eliminates the need  for a source
              of clean  air  in the field.  However, contamination
              from the  drying agent  can  be a problem.

9.2   The manual sampling consists of the sample  volume measuring
      apparatus shown in Figure 4 connected  to the cryogenic trap/
      GC assembly shown in  Figure 1.   The operation of this

-------
                    T03-7

assembly is described below.

9.2.1   Pump-Down Position

        The purpose of the pump-down mode of operation is to
        evacuate the ballast  tank in preparation for col-
        lecting a sample as illustrated in Figure 4.  (While in
        this position, helium can also be utilized to back-
        flush the sample line, trap, etc.  However,  this
        cleaning procedure is not normally needed during  most
        sampling operations).  The pump used for evacuating
        the system should be  capable of attaining 200 torr
        pressure.

9.2.2   Volume Measuring Position

        Once the system has been sufficiently evacuated,
        the 4-way ball valve  is switched to prepare for sample
        collection.  The 3-position valve is used to initiate
        sample flow while the needle valve controls the rate
        of flow.

9.2.3   Sample Volume Calculation

        The volume of air that has passed through the col-
        lection trap corresponds to a known change in pressure
        within the ballast tank (as measured by the Wallace
        Tiernan gauge).  Knowing the volume, pressure change,
        and temperature of the system, the ideal gas law  can
        be used to calculate  the number of moles of air
        sampled.  On a volume basis, this converts to the
        following equation:

                   _  AP      298
                      760    TA+ 273

-------
                               T03-8

                    where

                         Vs  = Volume sampled  at  760  mm Hg  pressure  and
                              25°C.
                         AP  = Change in  pressure within the  ballast tank,
                              mm of Hg.
                         V  = Volume of  ballast  tank and gauge.
                         TA  = Temperature  of  ballast tank, °C.

                    The internal  volume  of the ballast tank  and  gauge
                    can be determined either  by  H20  displacement or by
                    injecting calibrated volumes of  air into the system
                    using large volume syringes, etc.

10.   Sampling and Analysis  Procedure -  Manual Device

      10.1   This procedure assumes  the use of the manual sampling system
            described in Section 9.2
      10.2   Prior to sample  collection,  the entire assembly  should
            be leak-checked.   This  task  is accomplished by sealing
            the sampling inlet line, pumping  the unit down and placing
            the unit in the  flow measuring mode  of operation.  An initial
            reading on the absolute pressure  gauge is taken  and  rechecked
            after 10 minutes.  No apparent change should be  detected.
      10.3   Preparation for  sample  collection is carried out by  switching
            the 6-port valve to the "fill" position  and connecting  the
            heated sample line to the sample  source.  Meanwhile  the
            collection trap  is heated to 150°C (or other appropriate
            temperature). The volume measuring  apparatus  is pumped-down
            and switched to  the flow measuring mode.  The  3-position
            valve is opened  and a known  volume of sample is  then passed
            through the heated sample line.and trap  to purge the
            system.

-------
                                TO 3-9
      10.4  After the system purge is completed,  the  3-position  valve  is
            closed and the corresponding  gauge  pressure  is  recorded.
            The collection trap is then  immersed  into a  dewar  of liquid
            argon (or liquid oxygen)  and  the  3-position  valve  is
            temporarily opened to draw in a  known volume of air, i.e.
            a change in pressure corresponds  to a specific  volume of
            air (see Section 9).  Liquid  nitrogen cannot be used as the
            cryogen since it will also condense oxygen from the  air.
            Liquid oxygen represents  a potential  fire hazard and should
            not be employed unless absolutely necessary.
      10.5  After sample collection is completed, the 6-port valve is
            switched to the inject position,  the  dewar is removed and
            the trap is heated to 150°C  to transfer the  sample components
            to the head of the GC column  which  is initially maintained
            at -50°C.  Temperature programming  is initiated to elute
            the compounds of interest.
      10.6  A GC integrator (or data  system  if  available) is activated
            during the injection cycle to provide component identification
            and quantisation.

11.    Sampling and Analysis Procedure -  Automated Device

      11.1  This procedure assumes the use of the automated system shown
            in Figure 3.  The components  of  this  system  are discussed
            in Section 9.1.
      11.2  Prior to initial sample collection  the entire assembly should
            be leak-checked.  This task   is  completed by sealing the
            sample inlet line and noting  that the flow indication or the
            mass flow controller drops to zero  (less  than 1 mL/minute).
      11.3  The sample trap, valve, and  transfer  line are heated to
            120°C and ambient air is  drawn through the apparatus
            (M50 mL/minute) for a period  of  time  5-10 minutes  to flush
            the system, with the sample  valve in  the  inject position.
            During this time the GC column is maintained at 150°C to
            condition the column.

-------
                               T03-10
      11.4  The sample trap is then cooled to -160 + 5°C using a
            controlled flow of liquid nitrogen.   Once the trap
            temperature has stabilized,sample flow through the
            trap is initiated by placing the valve in the inject
            position and the desired volume of air is collected.
      11.5  During the sample collection period  the GC column is
            stabilized at -50°C to allow for immediate injection
            of the sample after collection.
      11.6  At the end of the collection period  the valve is
            immediately placed in the inject position, and the
            cryogenic trap is rapidly heated to  120°C to desorb
            the components onto GC column.  The  GC temperature
            program and data acquisition are initiated at this
            time.
      11.7  At the desired time the  cryogenic  trap  is  cooled  to  -  160°C,
            the valve  is  returned  to the  collect  position  and  the  next
            sample  collection  is  initiated  (to coincide  with  the completion
            of the  GC  analysis  of  the previous sample).

12.    Calibration Procedure

      Prior to sample  analysis, and  approximately every  4-6  hours  there-
      after, a calibration standard  must be analyzed,  using  the  identical
      procedure employed  for ambient air samples  (either Section 10  or  11).
      This section  describes three alternative approaches for preparing
      suitable standards.

      12.1  Teflon® (on Tedlar®)  Bags

            12.1.1   The bag (nominal size; 20L)  is filled with zero  air
                    and leaked checked.   This can be easily accomplished
                    by placing a  moderate weight (text book) on the
                    inflated bag  and leaving overnight.   No visible  change
                    in bag volume indicates a good seal.  The bag should
                    also be equipped with a quick-connect fitting for
                    sample withdrawal and an insertion port for liquid
                    injections (Figure 2).

-------
                          T03-11

      12.1.2  Before preparing a  standard  mixture,  the  bag  is
              sequentially filled  and  evacuated  with zero air
              (5 times).   After the  5th  filling, a  sample blank
              is obtained  using the  sampling  procedure  outlined
              in Section  10.
      12.1.3  In order  to  prepare  a  standard  mixture, the bag  is
              filled with  a known  volume of zero air.   This  flow
              should be measured  via a calibrated mass  flow
              controller or equivalent flow measuring device.
              A  measured aliquot  of  each analyte of interest is
              injected  into the bag  through the  insertion port
              using  a microliter  syringe.  For those compounds
              with vapor pressures lower than benzene or for strongly
              adsorbed  species, the bag  should be heated
              (60°C)  oven)  during  the  entire  calibration period.
      12.1.4  To withdraw  a  sample for analysis,  the sampling line
              is directly  connected  to the bag.   Quick  connect
              fittings  allow this  hook-up to  be  easily  accomplished
              and also  minimizes bag contamination from labora-
              tory air.  Sample collection is initiated as described
              earlier.

12.2  Glass Flasks

      12.2.1  If a  glass  flask is  employed  (Figure 2)  the exact
              volume is determined by  weighing the  flask before
              and after filling with deionized water.   The flask
              is dried  by  heating  at 200°C.
      12.2.2  To prepare a standard, the dried flask is flushed with
              zero air  until cleaned (i.e. a  blank  run  is made).
              An appropriate aliquot of  each  analyte is injected
              using  the same procedures  as described for preparing
              bag standards.
      12.2.3  To withdraw  a standard for analysis, the GC
              sampling  line is directly  connected to the flask
              and a  sample obtained.   However, because  the flask

-------
                         T03-12

              is a rigid container, it will  not remain at
              atmospheric pressure after sampling has  commenced.
              In order to prevent room air leakage into the flask,
              it is recommended that no more than 10%  of the initial
              volume be exhausted during the calibration period
              (i.e. 200 cc if a 2 liter flask is  used).

12.3  Pressurized Gas Cylinders

      12.3.1   Pressurized gas cylinders containing selected analytes
              at ppb concentrations in air can be prepared  or
              purchased.   A limited number of analytes (e.g.
              benzene, propane) are available from NBS.
      12.3.2   Speciality gas suppliers will  prepare custom  gas
              mixtures, and will  cross reference  the analyte
              concentrations to an NBS standard for an additional
              charge.  In general, the user  should purchase such
              custom mixtures,  rather than attempting  to prepare
              them because of the special  high pressure filling
              apparatus required.  However, the  concentrations should
              be  checked,  either  by the  supplier  or  the  user using
              NBS reference materials.
      12.3.3   Generally,  aluminum cylinders  are suitable since  most
              analytes of potential interest in this method have
              been shown to be  stable for  at least several  months
              in such cylinders.   Regulators constructed of stainless
              steel and Teflon®  (no silicon or neoprene rubber).
      12.3.4   Before use the tank regulator  should be  flushed by
              alternately pressuring with  the tank mixture, closing
              the tank valve, and venting  the regulator contents to
              the atmosphere several  times.
      12.3.5   For calibration a continuous flow of the gas  mixture
              should be maintained through a glass or  Teflon® manifold
              from which the calibration standard is drawn.  To
              generate various  calibration concentrations the

-------
                               T03-13

                    pressurized gas  mixture  can  be  diluted,  as  desired,
                    with zero grade  air using  a  dynamic  dilution  system
                    (e.g.  CSI Model  1700 ).

13.    Calibration Strategy

      13.1   Vapor phase standards can be prepared with either neat
            liquids or diluted liquid mixtures depending upon the
            concentration levels desired.   It  is recommended that benzene,
            also be included in this preparation scheme  so  that flame
            ionization detector response factors, relative  to benzene,
            can be determined for the other  compounds.   The  benzene
            concentration generated  in this  fashion should  be cross-
            checked with an NBS (e.g. SRM 1805)  for accuracy determina-
            tions.
      13.2   Under normal conditions, weekly  multipoint calibrations
            should be conducted.  Each multipoint calibration should
            include a blank run and  four concentration levels for the
            target species.  The generated concentrations should  bracket
            the expected concentration of ambient air samples.
      13.3   A plot of nanograms injected versus  area using  a linear
            least squares fit of the calibration data will yield  the
            following equation:

                               Y = A + BX

            where

                               Y = quantity  of component, nanograms
                               A = intercept
                               B = slope (response  factor)

            If substantial nonlinearity is present  in the calibration
            curve a quadratic fit of the data  can be used:

-------
                              T03-14

                           Y = A +  BX + CX2
            where
                           C = constant

            Alternatively,  a,  stepwise  multilevel calibration scheme
            may be  used  if  more  convenient for the data system in use.


14.    Performance Criteria  and Quality  Assurance

      This section  summarizes the quality assurance  (QA)  measures and
      provides guidance  concerning  performance criteria which should  be
      achieved within each  laboratory.

      14.1  Standard Operating Procedures (SOPs)

            14.1.1   Each user should generate SOPs describing the
                    following activities as  accomplished  in  their
                    laboratories:

                    1)   assembly,  calibration and operation of
                         the sampling system.
                    2)   preparation and handling of calibration
                         standards.
                    3)   assembly,  calibration and operation of the
                         GC/FID system and
                    4)   all aspects of data recording and  processing.

-------
                         T03-15
      14.1.2   SOPs  should  provide  specific  stepwise  instructions
              and should be  readily available to, and understood
              by, the  laboratory personnel  conducting the work.

14.2  Method  Sensitivity,  Precision  and Accuracy

      14.2.1   System sensitivity  (detection limit)  for  each
              component is calculated from the  data obtained  for
              calibration  standards.   The  detection limit  is
              defined  as

                          DL =  A + 3.3S

              where

                          DL =  calculated  detection limit  in
                               nanograms injected.
                          A   =  intercept calculated  in Section 13.
                          S   =  standard deviation of replicate
                               determination of the lowest level
                               standard (at least three  deter-
                               minations are required).

              For many compounds detection  limits of 1  to  5
              nanograms are  found  using the flame ionization
              detection.   Lower detection  limits can be  obtained
              for chlorinated hydrocarbons  using the electron
              capture  detector.
      14.2.2   A precision  of +  5%  (relative standard deviation)
              can be readily achieved at concentrations  10
              times the detection  limit.   Typical performance
              data  are included in Table 1.
      14.2.3   Method accuracy is estimated  to be within  +  10%,
              based on National Bureau of  Standard  calibrated
              mixtures.

-------
                               T03-16


                             REFERENCES


 1.    Holdren,  M.,  Spicer,  C.,  Sticksel, P., Nepsund,  K., Ward, G.,
      and  Smith,  R.,  "Implementation and Analysis of Hydrocarbon
      Grab Samples  from  Cleveland  and  Cincinnati 1981  Ozone Monitoring
      Study",  EPA-905/4-82-001.  U.S.  Environmental Protection Agency,
      Research  Triangle  Park,  North Carolina,1982.

 2.    Westberg, H.,  Rasmussen,  R., and Holdren, M., "Gas Chromatographic
      Analysis  of Ambient Air for  Light Hydrocarbons Using a  Chemically
      Bonded  Stationary  Phase",  Anal.  Chem. 46, 1852-1854, 1974.

 3.    Lonneman, W.  A., "Ozone and  Hydrocarbon Measurements in Recent
      Oxidant Transport  Studies",  in  Int.  Conf. on  Photochemical  Oxidant
      Pollutant and Its  Control  Proceedings, EPA-600/3-77-001a, 1977.

 4.    Singh,  H.,  "Guidance  for the Collection and  Use  of Ambient  Hydrocarbon
      Species Data  in Development  of Ozone Control  Strategies", EPA-450/4-
      80-008.   U.S.  Environmental  Protection Agency, Research Triangle
      Park, North Carolina, 1980.

 5.    Riggin, R.  M., "Technical  Assistance Document for Sampling  and
      Analysis of Toxic  Organic Compounds  in Ambient Air", EPA-600/4-83-027.
      U.S. Environmental Protection Agency, Research Triangle Park,
      North Carolina, 1983.

 6.    Annual  Book of ASTM Standards,  Part  11.03,  "Atmospheric Analysis1,1
      American Society for  Testing and Materials, Philadelphia, Pennsylvania,
      1983.

 7.    Foulger,  B.  E.  and P. G.  Sinamouds,  "Drier for Field Use in the
      Determination of Trace Atmospheric Gases", Anal.  Chem., 51, 1089-1090,
      1979.

 8.    Pheil,  J. D.  and W. A. McClenney, "Reduced Temperature  Preconcentration
      Gas  Chromatographic Analysis of  Ambient Vapor-Phase Organic Compounds:
      System Automation", Anal.  Chem., submitted,  1984.

 9.    Holdren,  M.  W0 W.  A.  McClenney,  and  R. N. Smith  "Reduced Temperature
      Preconcentration and  Gas Chromatographic Analysis of Ambient Vapor-
      Phase Organic Compounds:   System Performance", Anal. Chem.,
      submitted,  1984.

10.    Holdren,  M.,  S. Rust, R.  Smith,  and  J. Koetz, "Evaluation of
      Cryogenic Trapping as a Means for Collecting  Organic Compounds  in
      Ambient Air", Draft Final  Report on  Contract  No.  68-02-3487, 1984.

-------
                               T03-17

                       REFERENCES (Continued)
11.    Cox R.  D.  and R.  E.  Earp,"Determination of Trace Level  Organics
      in Ambient Air by High-Resolution  Gas  Chromatography with
      Simultaneous Photoiom'zation and Flame lonization Detection",
      Anal. Chem. !54, 2265-2270,  1982.

12.    Burns W. F., 0. T.  Tingy, R. C.  Evans  and E.  H.  Bates,
      "Problems  with a  Nafion® Membrane  Dryer for Chromatographic
      Samples",  J. Chrom.  269,  1-9,  1983.

-------
                              T03-18
Sample Volume
Measuring Apparatus
                                           Heated Sample Line
       G.C. Carrier
       Gas
        Variac
     Temperature
      Controller
 Sample Source
                                a. Fill Position
Sample Volume
Measuring Apparatus
                                         Heated Sample Line
Sample Source
       G.C. Carrier
       Gas
  .C. Column
        Variac
     Temperature
      Controller
                              b.  Injection Position

    Figure  1.   Schematic  of Six-Port Valve  Used  for  Sample
                 Collection.

-------
                              T03-19
                                             Septum Seal
                 Glass/Teflon Valve
                                                 \        '
Pin hole Insertion,
Port or Septum
Injection Port
 20 Liter
Teflon Bag
• Quick Connect
 Sampling Port
     Figure 2.   Dilution  Containers  for  Standard Mixtures

-------
     Cryogenic
     Sampling
     Electronics
      Console
 Voltage to Solenoid
Liquid
                                                                    Mass
                                                                    Flow
                                                                 Controller
                      Voltage to
                       Cartridge
                       Heaters
Vent
                                                        Gas Chromatographic System
                             o
                             oo
                              FIGURE 3.  AUTOMATED SAMPLING AND ANALYSIS
                                         SYSTEM FOR CRYOGENIC TRAPPING

-------
                                  T03-21
                            Pump>
                                                  Vent
                                                4 Way Bail Valve          / Shut Off Valve

                                                                  r-4
                                                                             Helium Tank
                                         Needle Valve
                                                  3 Position Valve
                                                     (1) Gas Chromatograph 6-Port Valve
                                                     (2) (Optional 2nd GC System)
                                                     (3) Off
                         (a) Volume Measuring Position
                            Pump,
                                                    Vent
                                                  4 Way Ball Valve

                                Shut Off Valve
                                                                             Helium Tank
          Ballast Tank
Needle Valve
                                                   3 Position Valve
                                                      (1) Gas Chromatograph 6-Port Valve
                                                      (2) (Optional 2nd GC System)
                                                      (3) Off
                                    1   2
                          (b) Pump - Down Position

Figure  4.   Sample Volume  Measuring Apparatus

-------
               TABLE 1.   VOLATILE  ORGANIC  COMPOUNDS  FOR  WHICH  THE  CRYOGENIC  SAMPLING
                         METHOD HAS  BEEN EVALUATED^)
Compound
Vinylidene Chloride
Chloroform
1 ,2-Dichloroethane
Methyl chloroform
Benzene
Trichloroethylene
Tetrachl oroethyl ene
Chlorobenzene
Retention Time,
Minutes(b/
9.26
12.16
12.80
13.00
13.41
14.48
17.37
18.09
Test 1
(4 runs, 200cc
Mean
(ppb)
144
84
44
63
93
84
69
46
samples)
%RSD
4.4
3.8
3.7
4.5
4.0
3.7
3.7
3.3
Test 2
(8 runs, 200-cc
Mean
(ppb)
6.1
3.5
1.9
2.7
3.9
3.5
2.9
1.9
samples)
%RSD
3.9
5.8
5.1
4.9
5.1
4.1
4.3
3.2
a)Recovery efficiencies were 100 + 5% as determined by comparing direct sample loop (5cc)  injections
  with cryogenic collection techniques (using test 1  data).  Data from reference 10.
b)GC conditions as follows:
          Column - Hewlett Packard, crosslinked methyl silicone, 0.32 mm ID x 50 m long,  thick
                   film, fused silica.
          Temperature Program - 50°C for 2 minutes, then increased  at 8°C/minute to 150°C.
                                                                                                           I
                                                                                                           CO
                                                                                                           t-0

-------
                                METHOD T04               Revision 1.0
                                                         April, 1984
        METHOD FOR THE DETERMINATION OF ORGANOCHLORINE PESTICIDES
              AND POLYCHLORINATED BIPHENYLS IN AMBIENT AIR
1.     Scope

       1.1   This document describes a method for determination of a
             variety of organochlorine pesticides and polychlorinated
             biphenyls (PCBs) in ambient air.  Generally, detection
                              3
             limits of >1 ng/m  are achievable using a 24-hour sampling
             period.
       1.2   Specific compounds for which the method has been employed
             are listed in Table 1.  Several references are available
             which provide further details on the development and
             application of the method.  The sample cleanup and analysis
             methods are identical to those described in U. S. EPA Method
             608.  That method is included as Appendix A of this methods
             compendium.

2.     Applicable Documents

       2.1   ASTM Standards
                D1356 Definition of Terms Related to
                Atmospheric Sampling and Analysis (7).
       2.2   Other Documents
                Ambient Air Studies (1-3)
                U.  S. EPA Technical Assistance Document (4).
                U.  S. EPA Method 608 (5).  See Appendix A of  methods
                compendium.

3.      Summary of Method

       3.1   A modified high volume sampler consisting  of a glass
             fiber filter with a polyurethane foam (PUF)  backup
             absorbent cartridge is used to sample ambient air at
             a rate of -^200-280 L/minute.

-------
                                 T04-2
       3.2   The filter and PUF cartridge are placed in clean, sealed
             containers and returned to the laboratory for analysis.
             The PCBs and pesticides are recovered by Soxhlet extraction
             with 5% ether in hexane.
       3.3   The extracts are reduced in volume using Kuderna-Danish (K-D)
             concentration techniques and subjected to column chroma-
             tographic cleanup.
       3.4   The extracts are analyzed for pesticides and PCBs using gas
             chromatography with electron capture detection (GC-ECD), as
             described in U. S. EPA Method 608 (5).
4.     Significance
       4.1   Pesticides, particularly organochlorine pesticides,  are widely
             used in both rural  and urban areas for a variety of  applications.
             PCBs are less widely used, due to extensive restrictions placed
             on their manufacture.  However, human exposure to PCBs
             continues to be a problem because of their presence  in
             various electrical  products.
       4.2   Many pesticides and PCBs  exhibit bioaccumulative,  chronic health
             effects and hence monitoring  ambient air for such  compounds
             is of great importance.
       4.3   The relatively low levels of  such  compounds in  the environment
             requires the use of high  volume sampling techniques  to
             acquire sufficient sample for analysis.   However,  the volatility
             of these compounds prevents efficient collection on  filter
             media.   Consequently, this method utilizes both a  filter and
             a PUF backup cartridge which  provides for efficient  collection
             of most organochlorine pesticides, PCBs, and many other organics
             within  the same volatility range.
5.      Definitions
             Definitions used in this document and any user-prepared SOPs
             should be consistent with ASTM D1356  (7).  All  abbreviations

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                               T04-3

             and symbols are defined within this document at the point of
             use.

6.     Interferences

       6.1   The use of column chromatographic cleanup and selective GC
             detection (GC-ECD) minimizes the risk of interference from
             extraneous organic compounds.   However, the fact that PCBs
             as well as certain organochlorine pesticides (e.g.  toxaphene
             and chlordane) are complex mixtures of individual  compounds
             can cause difficulty in accurately quantifying a particular
             formulation in a multiple component mixture.
       6.2   Contamination of glassware and sampling apparatus  with traces
             of pesticides or PCBs can be a major source of error in the
             method, particularly when sampling near high level  sources
             (e.g.  dumpsites, waste  processing plants,  etc.)  careful  attention
             to cleaning and handling procedures is required in  all  steps
             of the sampling and analysis to minimize this source of error.

7.     Apparatus

       7.1   Hi-Vol Sampler with PDF cartridge - available from  General
             Metal  Works (Model PS-1).  See Figure 1.
       7.2   Sampling Head to contain  glass cartridge with PUF plug - available
             from General  Metal Works.  See Figure 2.
       7.3   Calibration orifice - available from General Metal  Works.
       7.4   Manometer - to use with calibration orifice.
       7.5   Soxhlet extraction system - including Soxhlet extractors
             (500 and 250 ml),  heating mantels, variable voltage trans-
             formers, and cooling water source - for extraction  of PUF
             cartridges before  and after sampling.   Also for extraction of
             filter samples.
       7.6   Vacuum oven connected to water aspirator - for drying
             extracted PUF cartridges.
       7.7   Gas chromatograph  with  electron capture detector -  (consult
             U.  S.  EPA Method 608 for specifications).

-------
                                T04-4
       7.8   Forceps - to handle quartz  fiber  filter  samples.
       7.9   Die - to cut PUF plugs.
       7.10  Various items for extract preparation, cleanup, and analysis
             consult U.  S. EPA Method 608 for  detailed listing.
       7.11  Chromatography column -  2 mm I.D. x 15 cm long - for alumina
             cleanup.

8.     Reagent and Materials

       8.1   Polyurethane foam - 3 inch  thick  sheet stock,  polyether
             type used in furniture upholstering.   Density  0.022 g/cm .
       8.2   Polyester gloves - for handling PUF cartridges and  filters
       8.3   Filters, quartz fiber -  Pallflex  2500 QAST  , or equivalent.

       8.4   Wool felt filter - 4.9 mg/cm2 and 0.6 mm thick.  To fit
             sample head for collection  efficiency studies.  Pre-
             extracted with 5% diethyl  ether in hexane.
       8.5   Hexane - Pesticide or distilled in glass grade.
       8.6   Diethyl ether - preserved with 2% ethanol  - distilled in
             glass grade, or equivalent.
       8.7   Acetone - Pesticide or distilled  in glass  grade.
       8.8   Glass container for PUF  cartridges.
       8.9   Glass petri dish - for shipment of filters  to  and from the
             laboratory.
       8.10  Ice chest - to store samples at M)°C  after  collection.
       8.11  Various materials needed for extract  preparation, cleanup,
             and analysis - consult U.  S. EPA  Method  608 for details
             (Appendix A of this compendium).
       8.12  Alumina - activity grade IV. 100/200 mesh

9.     Assembly and Calibration of Sampling Apparatus

       9.1   Description of Sampling  Apparatus
             9.1.1   The entire sampling system is diagrammed in Figure  1.
                     This sampler was developed by Syracuse University

-------
                        T04-5

              Research Corporation (SURC) under a U. S. EPA
              contract (6) and further modified by Southwest
              Research Institute and the U.  S. EPA.   A unit
              specifically designed for this method  is now commer-
              cially available (Model  PS-1  - General Metal Works,
              Inc., Village of Cleves, Ohio).  The method
              writeup assumes the use  of the commercial device,
              although the earlier modified  device is also con-
              sidered acceptable.
      9.1.2   The sampling module (Figure 2) consists of a glass
              sampling cartridge and an air-tight metal cartridge
              holder.  The PUF plug is retained in the glass
              sampling cartridge.

9.2   Calibration of Sampling System

      9.2.1   The airflow through the  sampling system is monitored
              by a venturi/Manehelic assembly, as shown in Figure 1.
              A  multipoint calibration of the venturi/mag-
              nehelic assembly must be conducted every six months
              using an audit calibration orifice, as described in
              the U. S. EPA High Volume Sampling Method (8).  A
              single point calibration must  be performed before
              and after each sample collection, using the procedure
              described below.
      9.2.2   Prior to calibration a "dummy" PUF cartridge and
              filter are placed in the sampling head and the sampling
              motor  is activated.  The flow  control  valve is
              fully opened and the voltage  variator  is adjusted
              so that  a sample flow rate corresponding to i/110% of
              the desired flow rate is indicated on  the magnehelic
              (based on the previously obtained multipoint cali-
              bration curve).  The motor is  allowed  to warmup
              for VI0 minutes and then the  flow control valve is
              adjusted to achieve the  desired flow rate.   The
              ambient temperature and  barometric pressure should

-------
                                T04-6

                     be recorded on an appropriate data sheet (e.g. Figure 3)
             9.2.3   The calibration orifice is then placed on the sampling
                     head and a manometer is attached to the tap on the
                     calibration orifice.  The sampler is momentarily
                     turned off to set the zero level of the manometer.
                     The sampler is then switched on and the manometer
                     reading is recorded, once a stable reading is
                     achieved.   The sampler is then shut off.
             9.2.4   The calibration curve for the orifice is  used to
                     calculate  sample flow from the data obtained in
                     9.2.3, and the calibration curve for the  venturi/
                     magnehelic assembly is used to calculate  sample
                     flow from  the data obtained in 9.2.2.  The calibra-
                     tion data  should be recorded on an appropriate
                     data sheet (e.g. Figure 3).  If the  two values  do
                     not agree  within 10% the sampler should be inspected
                     for damage, flow blockage,  etc.   If  no obvious  problems
                     are found  the sampler should be recalibrated (multi-
                     point) according to the U.  S.  EPA High Volume
                     Sampling procedure (8).
             9.2.5   A multipoint calibration of the  calibration orifice,
                     against a  primary standard, should be obtained
                     annually.

10.     Preparation of Sampling  (PUF) Cartridges

       10.1   The PUF adsorbent  is a polyether-type  polyurethane foam
             (density No.  3014  or 0.0225 g/cm3).  This type of foam
             is used for furniture upholstery.   It  is white and yellows
             on exposure to light.
       10.2   The PUF inserts are 6.0 cm diameter cylindrical plugs cut
             from 3 inch sheet  stock and should  fit with slight com-
             pression in the glass cartridge, supported by the wire

-------
                              T04-7
            screen.  See Figure 2.  During cutting the die is rotated
            at high speed (e.g. in a drill press) and continuously
            lubricated with water.
      10.3  For initial cleanup the PUF plug is placed in a Soxhlet
            extractor and extracted with acetone for 14-24 hours at
            approximately 4 cycles per hour.  When cartridges are
            reused, 5% diethyl ether in n-hexane can be used as  the
            cleanup solvent.
      10.4  The extracted PUF is placed in a vacuum oven connected
            to a water aspirator and dried at room temperature for
            approximately 2-4 hours (until no solvent odor is detected).
      10.5  The PUF is placed into the glass sampling  cartridge using
            polyester gloves.  The module is wrapped with hexane
            rinsed aluminum foil,  placed in a labeled container
            and tightly sealed.
      10.6  Other adsorbents may be suitable for this method as  indicated
            in the various references (1-3).  If such materials  are
            employed the user must define appropriate preparation
            procedures based on the information contained in these
            references.
      10.7  At least one assembled cartridge from each batch must be
            analyzed, as a laboratory blank, using the procedures
            described in Section 12, before the batch is considered
            acceptable for field use.  A blank level  of <10 ng/plug
            for single compounds is considered to be acceptable.  For
            multiple component mixtures (e.g. Arochlors) the blank level
            should be <100 ng/plug.
11.   Sampling
      11.1   After the sampling system has  been  assembled  and  calibrated
            as described in Section 9 it can  be used  to collect  air
            samples as described below.
      11.2   The samples should be located  in  an unobstructed  area, at
            least two meters from any obstacle  to  air flow.   The
            exhaust hose should be stretched  out in the downwind

-------
                         T04-8
     direction to prevent recycling of air.
11.3 A clean sampling cartridge and quartz fiber filter are removed
     from sealed transport containers and placed in the sampling
     head using forceps and gloved hands.  The head is tightly sealed
     into the sampling system.   The aluminum foil  wrapping is
     placed back in the sealed  container for later use.
11.4 The zero reading of the Magnehelic is checked.  Ambient
     temperature, barometric pressure, elapsed time meter setting,
     sampler serial number, filter number and PUF cartridge number
     are recorded.  A suitable  data sheet is shown in Figure 4.
11.5 The voltage variator and flow control valve are placed at the
     settings used in 9.2.3 and the power switch is turned on.
     The elapsed time meter is  activated and the start time recorded.
     The flow (Magnehelic setting) is adjusted, if necessary using
     the flow control valve.
11.6 The Magnehelic reading is  recorded every six hours during
     the sampling period.  The  calibration curve (Section 9.2.7) is
     used to calculate the flow rate.  Ambient temperature and
     barometric pressure are recorded at the beginning and end of
     the sampling period.
11.7 At the end of the desired  sampling period the power is turned
     off and the filter and PUF cartridges are wrapped with the
     original aluminum foil and placed in sealed, labeled containers
     for transport back to the  laboratory.
11.8 The Magnehelic calibration is checked using the calibration
     orifice as described in Section 9.2.4.   If the calibration
     deviates by more than 10% from the initial reading the flow data
     for that sample must be marked as suspect and the sampler
     should be inspected and/or removed from service.
11.9 At least one field blank will be returned to  the laboratory
     with each group of samples.  A field blank is treated exactly
     as a sample except that no air is drawn through the cartridge.

-------
                              T04-9
      11.10 Samples are stored at ^20°C in an ice chest until receipt at
            the analytical  laboratory,  at which time they are stored
            refrigerated at 4°C.

12.    Sample Preparation and Analysis

      12.1   Sample Preparation

            12.1.1   All  samples  should  be extracted  within 1  week  after
                    collection.
            12.1.2  PDF cartridges  are  removed  from  the sealed  con-
                    container using gloved hands, the aluminum  foil
                    wrapping is  removed,  and  the cartridges  are placed
                    into a  500-mL Soxhlet extraction.  The cartridges are
                    extracted for 14-24 hours at ^4  cycles/hour with 5%
                    diethyl  ether in hexane.  Extracted cartridges can be
                    dried and reused following  the handling  procedures
                    in  Section 10.   The quartz  filter can  be  placed in
                    the  extractor with  the PUF  cartridges.   However, if
                    separate analysis is  desired then  one  can proceed with
                    12.1.3.
            12.1.3  If  separate  analysis  is desired,  quartz  filters are
                    placed  in a  250-mL Soxhlet  extractor  and  extracted
                    for  14-24 hours with  5% diethyl  ether  in  hexane.
            12.1.4  The  extracts are concentrated to  10 ml final
                    volume  using 500-mL Kuderna-Danish concentrators
                    as  described in EPA Method  608 (5), using a hot water
                    bath.   The concentrated extracts  are  stored refrigerated
                    in  sealed 4-dram vials  having teflon-lined  screw-caps
                    until analyzed  or subjected to cleanup.

      12.2   Sample  Cleanup

            12.2.1   If only  organochlorine pesticides and  PCBs  are sought,
                    an alumina cleanup procedure reported  in the literature
                    is appropriate  (1).   Prior  to cleanup  the sample

-------
                                T04-10
                   extract is carefully reduced to 1 ml using a gentle
                   steam of clean nitrogen.
           12.2.2  A glass chromatographic column (2 mm ID x 15 cm long)
                   is packed with alumina, activity grade IV and rinsed
                   with ^20 ml of n-hexane.  The concentrated sample
                   extract (from 12.2.1) is placed on the column and
                   eluted with 10 ml of n-hexane at a rate of 0.5
                   mL/minute.  The eluate volume is adjusted to
                   exactly 10 mL and analyzed as described in 12.3.
           12.2.3  If other pesticides are sought, alternate cleanup
                   procedures (e.g. Florisil) may be required.  Method
                   608 (5) identifies appropriate cleanup procedures.

      12.3 Sample  Analysis

           12.3.1  Sample analysis  is  performed  using GC/ECD  as
                   described  in  EPA Method 608  (5).  The  user  must
                   consult  this  method for detailed  analytical procedures.
           12.3.2  GC  retention  times  and  conditions are  identified
                   in  Table  1 for  the  compounds  of  interest.

13.    GC Calibration

      Appropriate calibration  procedures  are  identified  in EPA Method
      608 (5).

14.    Calculations

      14.1 The total  sample volume (\fn)  is calculated  from the
            periodic  flow readings  (Magnehelic)  taken in Section
            11.6 using the  following equation.
                                Q,  + Qp ... QN    T
                          Mn= —!	-x	
                                         N      1000
            where

-------
                          T04-11

                                          3
               V  = Total sample volume (m ).
               Q,, O-.-.Q^ = Flow rates determined at the
                    beginning, end, and intermediate points during
                    sampling (L/minute).
               N = Number of data points averaged.
               T = Elapsed sampling time (minutes).
14.2  The volume of air sampled can be converted to  standard
      conditions (760 mm Hg pressure and 25°C) using the following
      equation:
                         p
                          A
               V  = V  X
                s    m
                         760    273+tA
      where
               V  = Total  sample volume at 25°C and 760 mm Hg
                               3
                    pressure (m )
               V  = Total  sample flow under ambient conditions (m )
               P^ = Ambient pressure (mm Hg)
              t . = Ambient temperature (°C)

14.3  The concentration of compound in the sample is calculated
      using the  following  equation:
                     A x Vc
               CA =
                     V.XVS
      where
               C.  = Concentration of analyte in the sample,
                        3
                    yg/m
               A  = Calculated amount of material  injected onto
                    the chromatograph based on calibration curve
                    for injected standards  (nanograms)
               V.j  = Volume of extract injected (yL).

-------
                                T04-12

                        V  = Final volume of extract (ml).
                        V  = Total  volume of  air  samples  corrected  to
                         •*                          o
                             standard  conditions  (m ).

14.    Performance Criteria  and  Quality Assurance

      This section summarizes the quality assurance (QA)  measures and
      provides  guidance  concerning  performance  criteria which  should
      be achieved within each laboratory.

      14.1   Standard  Operating  Procedures (SOPs)

            14.1.1  Users should generate SOPs  describing the  follow-
                   ing  activities as  accomplished  in their laboratory:
                   1) assembly, calibration and  operation of  the
                   sampling system, 2) preparation, purification,  storage
                   and  handling of sampling cartridges,  3) assembly,
                   calibration and operation of  the GC/ECD system, and
                   4) all  aspects of  data recording and  processing.
            14.1.2  SOPs  should provide specific  stepwise instructions
                   and  should  be readily available to, and understood
                   by,  the  laboratory  personnel  conducting the work.

      14.2   Process,  Field,  and Solvent Blanks

            14.2.1  One  PUF  cartridge and filter  from each batch of
                   approximately twenty should be  analyzed, without
                   shipment to the field, for the  compounds of
                   interest to serve as a process  blank.
            14.2.2  During each sampling episode  at least one  PUF
                   cartridge and filter should be  shipped to  the field
                   and  returned, without drawing air through  the sampler,
                   to serve as a field blank.
            14.2.3  During the analysis of each batch of samples at
                   least one solvent process blank (all steps conducted
                   but  no PUF cartridge or filter  included) should be

-------
                          T04-13

              carried through the procedure  and  analyzed.
      14.2.4  Blank levels should not exceed ^10 ng/sample  for
              single components  or MOO  ng/sample for  multiple
              component mixtures (e.g. PCBs).

14.3  Collection Efficiency and  Spike Recovery

      14.3.1  Before using the method for  sample analysis each
              laboratory must determine  their collection
              efficiency for the components  of interest.
      14.3.2  The glass fiber filter in  the  sampler  is replaced
              with a hexane-extracted wool felt  filter (weight
                        2
              14.9 mg/cm , 0.6 mm thick).  The filter  is spiked
              with microgram amounts of  the  compounds  of interest
              by dropwise addition of hexane solutions of the
              compounds.   The solvent is allowed to  evaporate
              and filter is placed into  the  sampling system for
              immediate use.
      14.3.3  The sampling system, including a clean PUF cartridge,
              is activated and set at the  desired sampling  flow
              rate.   The sample  flow is monitored for  24 hours.
      14.3.4  The filter and PUF cartridge are then  removed and
              analyzed as described in Section 12.
      14.3.5  A second sample, unspiked  is collected over the
              same time period to account  for any background
              levels of components in the  ambient air  matrix.
      14.3.6  A third PUF cartridge is spiked with the same amounts
              of the compounds used in 14.3. 2 and extracted to
              determine analytical  recovery.
      14.3.7  In general  analytical   recoveries  and  collection
              efficiencies of 75% are considered to  be acceptable
              method performance.

-------
                         T04-14

      14.3.8  Replicate (at least triplicate)  determinations of
              collection efficiency should  be  made.   Relative
              standard deviations for these replicate determinations
              of + 15% or less is considered acceptable  performance.
      14.3.9  Blind spiked samples should be included with sample
              sets periodically,  as a check on analytical  per-
              formance.

14.4  Method Precision and Accuracy

      Typical  method recovery data are shown in Table 1.   Re-
      coveries for the various chlorobiphenyls illustrate  the
      fact that all components of an Arochlor  mixture will  not
      be retained to the same extent.  Recoveries  for tetrachloro-
      biphenyls and above are generally greater than  85% but
      di- and trichloro homologs  may not be recovered quantitatively,

-------
                               T04-15
                             REFERENCES
1.   Lewis, R. G., Brown, A. R., and Jackson, M. D., "Evaluation
     of Polyurethane Foam for Sampling of Pesticides, Polychlorinated
     Biphenyls, and Polychlorinated Naphthalenes in Ambient Air",
     Anal. Chem. 49, 1668-1672, 1977.

2.   Lewis, R. G. and Jackson,  M. D., "Modification and Evaluation
     of a High-Volume Air Sampler for Pesticides and Semi volatile
     Industrial Organic Chemicals", Anal. Chem. j>4, 592-594, 1982.

3.   Lewis, R. G., Jackson, M.  D., and MacLeod, K. E., "Protocol for
     Assessment of Human Exposure to Airborne Pesticides", EPA-600/2-80-
     180, U.S. Environmental Protection Agency, Research Triangle
     Park, NC, 1980.

4.   Riggin, R. M., "Technical  Assistance Document for Sampling and
     Analysis of Toxic Organic  Compounds in Ambient Air", EPA-600/4-
     83-027., U. S. Environmental Protection Agency, Research Triangle
     Park, NC, 1983.

5.   Longbottom, J. E. and Lichtenberg, J. J., "Methods for Organic
     Chemical Analysis of Municipal and Industrial Wastewater",
     EPA-600/4-82-057, U. S. Environmental Protection Agency,
     Cincinnati, OH, 1982.

6.   Bjorkland, J., Compton, B., and Zweig, G., "Development of
     Methods for Collection and Analysis of Airborne Pesticides."
     Reportfor Contract  No. CPA 70-15, National Air Pollution Control
     Association, Durham, NC,  1970.

7.   Annual Book of ASTM Standards, Part 11.03, "Atmospheric Analysis",
     American Society for Testing and Materials, Philadelphia, PA,
     1983.

8.   Reference Method for the  Determination of Suspended  Particulates
     in the Atmosphere (High Volume Method).   Federal  Register,
     Sept. 14, 1972 or 40CFR50 Appendix B.

-------
                                     T04-16


TABLE 1.  SELECTED COMPONENTS DETERMINED USING HI-VOL/PUF SAMPLING PROCEDURE
24-Hour Sampling Efficiency(b)
GC Retention
Compound Time, Minutes'9)
Aldrin 2.4
4,4'-DDE 5.1
4,4'-DDT 9.4
Chlordane (c)
Chlorobiphenyls
4,4' Di-
2,4,5 Tri-
2, 4', 5 Tri-
2,2' ,5,5' Tetra-
2, 2', 4, 5, 5' Penta-
2, 2', 4, 4', 5, 5' Hexa
Air
Concentration
ng/m^
0.3-3.0
0.6-6.0
1.8-18
15-150

2.0-20
0.2-2.0
0.2-2.0
0.2-2.0
0.2-2.0
0.2-2.0
%
Recovery
28
89
83
73

62
36
86
94
92
86
   (a)    Data  from U.S.  EPA  Method  608.   Conditions  are  as  follows:

         Stationary Phase  -  1.5% SP2250/1.95%  SP-2401  on
         Supelcoport (100/120 mesh)  packed  in  1.8  mm long x
         4 mm  ID glass  column.

         Carrier - 5/95  methane/Argon  at  60 mL/Minute

         Column Temperature  - 160°C  except  for PCBs  which are
         determined at  200°C.

   (b)    From  Reference  2.

   (c)    Multiple component  formulation.  See  U.S. EPA Method  608.

-------
                              T04-17
 Magnehehc
   Gauge
  0-100 in.
                   Sampling
                     Head
                 (See Figure 2)
  Exhaust
    Duct
(6 in. xlOft)
                                                      Voltage Variator
                                                      Elapsed Time Meter
      FIGURE 1.  HIGH VOLUME AIR SAMPLER. AVAILABLE
                 FROM GENERAL METAL WORKS (MODEL PS-1)

-------
O


 I
    lU
    tC

-------
   Performed by_
   Date/Time
Calibration Orifice
Manometer S/N 	
S/N
 Ambient Temperature_
Bar.Press.
                                                            Hg
Sampler
S/N
















VaHac
Setting V
















Timer OK?
Yes/Ho
















Calibration Orifice
Data
Manometer,
in. H20
















Flow Rate,
scm /min(a)
















Sampler
Venturi Data
Magnehelic,
in. H20
















Flow Rate
scm/min (b)
















% Difference Between
Calibration and Sample
Venturi Flow Rates
















Comments
















                                                                                                                                                 o
                                                                                                                                                 -C-
                                                                                                                                                  I
(a)  From Calibration Tables  for Calibration Orifice or Venturi Tube
(b)  From Calibration Tables  for Venturi Tube in each H1-Vol  unit.
                                   Date check by
                                             Date
                                   FIGURE 3.   TYPICAL CALIBRATION  SHEET FOR  HIGH  VOLUME SAMPLER

-------
S«mpl*r
S/N




























Sampling Location
1 D




























N«w
FrttM K/t




























PUFCart
No




























Vance
Setting




























Clock Tim*
Stari, hf CDT




























Stop, hf CDT




























Mm Elapsed




























Sampler Timer
Start, mm




























Stop mm




























Mm Elapsed




























Ventur. Rmdmy Tima/Maynat>«4tc in H2O
1




























2




























3




























4




























Ambiant
Temperature, "C
Start




























Stop




























Barometric
Prassurt mm Hg
Start




























Stop




























•=«-"—




























                                                                                                                                                             o
                                                                                                                                                             J^
                                                                                                                                                              I
                                                                                                                                                             NJ
                                                                                                                                                             O
(a) Record iny flvtifonc* of Umpiring with Mmplvr and/or •bnormihtiM in wmplcr op«r«tion, PUF cartridge condition or handling, ate
                                                                             Data Chackad By.
                            FIGURE  4.    TYPICAL SAMPLING DATA FORM FOR HIGH VOLUME PESTICIDE/PCB SAMPLER

-------
                                 METHOD T05              Revision 1.0
                                                         April,  1984
   METHOD FOR THE DETERMINATION OF ALDEHYDES AND KETONES IN AMBIENT AIR
           USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC)

1.      Scope

       1.1   This document describes a method for determination of
             individual aldehydes and ketones in ambient air.   With
             careful attention to reagent purity and other factors
             the method can detect most monofunctional  aldehydes and
             ketones at the 1-2 ppbv level.
       1.2   Specific compounds for which the method has been  employed
             are listed in Table 1.  Several studies have used the
             same basic method, with minor procedural  differences,
             for analysis of ambient air (1-3).

2.      Applicable Documents

       2.1   ASTM Standards:
             D 1356 Definitions of Terms Related to Atmospheric
             Sampling and Analysis (s)

       2.2   Other Documents
             Ambient air studies (1-3).
             U.S. EPA Technical Assistance Document (4)

3.      Summary of Method

       3.1   Ambient air is drawn through a  midget  impinger containing  10 mL
             of 2N^ HC1/0.05% 2,4-dinitrophenylhydrazine (DNPH  reagent)
             and 10 mL of isooctane.   Aldehydes  and ketones  readily
             form stable 2,4-dinitrophenylhydrazones (DNPH derivatives).

-------
                                 T05-2
       3.2   The impinger solution  is placed in a screw-capped vial  having
             a teflon-lined cap and returned to the laboratory for analysis.
             The DNPH derivatives are recovered by removing the isooctane
             layer, extracting the  aqueous layer with 10 ml of 70/30
             hexane/methylene chloride,  and combining the organic
             layers.
       3.3   The combined organic layers are evaporated  to dryness under
             a steam of nitrogen and the residue dissolved in methanol.
       3.4   The DNPH derivatives are determined using reversed phase
             HPLC with an ultraviolet (UV) adsorption detector operated
             at 370 nm.
4.     Significance
       4.1   Aldehydes and ketones are emitted into the atmosphere from
             chemical operations and various combustion sources.   In
             addition, several  of these compounds (e.g. formaldehyde and
             acetaldehyde) are produced by photochemical  degradation
             of other organic compounds.   Many of these compounds are
             acutely toxic and/or carcinogenic, thus requiring their
             determination in ambient air in order to assess human
             health impacts.
       4.2   Conventional  methods for aldehydes and ketones  have  generally
             employed colorimetric techniques wherein only one or  two
             compounds are detected, or the sum of numerous  compounds
             is determined.   The method described herein  provides a
             means for specifically determining a wide variety of aldehydes
             and ketones at typical ambient concentrations.
5.     Definitions
       Definitions used in this document and any user prepared SOPs
       should be consistent with ASTM 01356(5).   All  abbreviations and
       symbols are defined within this document  at the point of use.

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                               T05-3

6.     Interferences

       6.1    The only significant interferences in the method are certain
             isomeric aldehydes or ketones which may be unresolved by
             the HPLC system.  Such interferences can often  be  overcome  by
             altering the separation conditions (e.g.  using alternate
             HPLC columns or mobile phase compositions).
       6.2   Formaldehyde contamination of the DNPH reagent is a
             frequently encountered problem.   The reagent must be
             prepared within 48 hours before  use and must be stored in
             an uncontaminated environment before and after sampling to
             minimize blank problems.  Acetone contamination is
             apparently unavoidable.  Consequently, the method cannot be
             used to accurately measure acetone levels except in highly
             contaminated environments.

7.     Apparatus

       7.1    Isocratic HPLC system-consisting of high pressure
             pump, injection valve, Zorbax ODS column (25 cm x 4.6 mm ID),
             variable wavelength UV detector, and data system or
             stripchart recorded.   See Figure 3.
       7.2   Sampling system-capable of accurately and precisely
             sampling 100-1000 mL/minute of ambient air.   See Figure 1.
       7.3   Stopwatch
       7.4   Friction top metal  can  e.g. one-gallon  (paint can) - to hold
             ONPH reagent and samples
       7.5   Thermometer -  to record ambient  temperature.
       7.6   Barometer (optional)
       7.7   Analytical  balance -  0.1 mg sensitivity
       7.8   Reciprocating  shaker
       7.9   Midget impingers - jet inlet type - 25 mL volume.
       7.10  Ice bath -  for cooling impingers during sampling.

-------
                                T05-4

       7.11  Nitrogen evaporator with heating block - for concentrating
             samples
       7.12  Suction filtration apparatus - for filtering HPLC
             mobile phase.
       7.13  Volumetric flasks - 100 ml and 500 ml.
       7.14  Pipettes - various sizes,  1-10 ml.
       7.15  Helium purge line (optional) - for degassing HPLC
             mobile phase.
       7.16  Erlenmeyer flask, 1-liter  - for preparing HPLC mobile
             phase.
       7.17  Graduated cylinder, 1  liter - for preparing HPLC mobile
             phase.
       7.18  Microliter syringe, 10-25  uL - for HPLC injector.

8.     Reagents and Materials

       8.1    Bottles, 10 oz.  glass,  with teflon-lined screw cap - for
             storing DNPH reagent.
       8.2    Vials, 50 mL,  with teflon-lined screw cap - for holding
             samples and extracts.
       8.3    Disposable pipettes and bulbs.
       8.4    Granular charcoal.
       8.5    Methanol, hexane, methylene chloride, isooctane -  distilled
             in glass or pesticide  grade.
       8.6    2,4-Dinitrophenylhydrazine - highest  purity available
             (20% moisture).
       8.7    Nitrogen, compressed gas cylinder -99.99% purity for
             sample evaporation.
       8.8    Polyester filters, 0.22 ym - Nuclepore or equiv.
       8.9    DNPH derivatives of  the  components of  interest  -
             synthesized from DNPH  and  neat aldehydes according
             to reference (7).  Recrystallized from ethanol before
             use.

-------
                               T05-5

9.     Preparation of DNPH Reagent

       9.1   Each batch of DNPH reagent should be prepared and purified
             within 48 hours of sampling, according to the procedure
             described in this section.
       9.2   Two hundred and fifty milligrams of solid 2,4-dinitro-
             phenylhydrazine and 90 ml of concentrated hydrochloric
             acid are placed into a 500 mL volumetric flask and the
             flask is filled to the mark with reagent water.  The
             flask is then inverted several times or sonified  until  all  of
             the solid material  has dissolved.
       9.3   Approximately 400 mL of the DNPH reagent is placed in a
             16 ounce glass screw-capped bottle having a teflon-lined
             cap.  Approximately 50 ml of a 70/30 (V/V) hexane/methylene
             chloride mixture is added to the bottle and the capped
             bottle is shaken for 15 minutes on a reciprocating shaker.
             The organic layer is then removed and discarded by decanting
             as much as possible and using a disposable pipette to
             remove the remaining organic layer.
       9.4   The DNPH reagent is extracted two more times as described
             in 9.3.  The bottle is then tightly capped, sealed with
             teflon tape, and placed in a friction top can (paint can)
             containing a 1-2 inch layer of granulated charcoal.  The
             bottle is kept in the sealed can prior to use.
       9.5   A portion of the DNPH reagent is analyzed using the
             procedure described in Section 11 prior to use in order to
             ensure that adequate background levels are maintained.

10.     Sampling

       10.1   The sampling  apparatus is  assembled  and  should  be  similar  to
             that shown  in  Figure  1.  EPA Method  6  uses  essentially  the  same
             sampling  system  (8).   All  glassware  (e.g.  impingers,  sampling
             bottles,  etc.) must be thoroughly  rinsed with methanol  and  oven
             dried  before  use.

-------
                       T05-6
10.2  Prior to sample collection the entire assembly (including
      empty sample impingers) is installed and the flow rate
      checked at a value near the desired rate.   In general
      flow rates of 100-1000 mL/minute are useful.   Flow rates
      greater than ^1000 mL/minute should not be  used because
      impinger collection efficiency may decrease.   Generally
      calibration is accomplished using a soap bubble flow
      meter or calibrated wet test meter connected to the flow
      exit, assuming the entire system is sealed.   ASTM Method
      D3686 describes an appropriate calibration  scheme not
      requiring a sealed flow system downstream of the pump.
10.3  Ideally a dry gas meter is included in the  system to record
      total flow.  If a dry gas meter is not available the operator
      must measure and record the sampling flow rate at the
      beginning and end of the sampling period to  determine
      sample volume.  If the sampling period exceeds two hours
      the flow rate should be measured at intermediate points
      during the sampling period.  Ideally a rotameter should be
      included to allow observation  of the flow rate without
      interruption of the sampling process.
10.4  To collect an air sample two clean midget impingers  are
      loaded with 10 ml of purified  DNPH reagent and 10 mL of
      isooctane.  The impingers are  connected in series to
      the sampling system and sample flow is started.   The follow-
      ing parameters are recorded on the data sheet (see Figure 3
      for an example):  date, sampling location, time, ambient
      temperature, barometric pressure (if available), relative
      humidity (if available), dry gas meter reading (if appro-
      priate), flow rate, rotometer  setting, DNPH  reagent batch
      number, and dry gas meter and  pump identification numbers.
10.5  The sampler is allowed to operate for the desired period,
      with periodic recording of the variables listed above.
      The total flow should not exceed %80 liters.  The operator
      must ensure that at least 2-3 ml of isooctane remains  in
      the first impinger at the end of the sampling interval
      (i.e. for high ambient temperatures lower sampling volumes
      may be required).

-------
                       T05-7
10.6  At the end of the  sampling  period  the  parameters listed
      in 10.4 are recorded  and  the  sample  flow is stopped.  If
      a dry gas meter is not  used the  flow rate must be checked
      at the end of the  sampling  interval.   If the flow rate
      at the beginning and  end  of the  sampling period differ
      by more than 15% the  sample should be  marked as suspect.
10.7  Immediately after  sampling  the impingers are removed from
      the sampling system.  The contents of  the first impinger
      are emptied into a clean  50 mL glass vial having a teflon-
      lined screw cap.  The first impinger is then rinsed with
      the contents of the second  (backup)  impinger and the rinse
      solution is added  to  the  vial.   The  vial is then capped,
      sealed with teflon tape and placed in  a friction top can
      containing 1-2 inches of  granular  charcoal.  The samples
      are stored in the  can,  refrigerated  until analysis.
10.8  If a dry gas meter or equivalent total flow indicator is
      not used the average  sample flow rate  must be calculated
      according to the following  equation:

                      Q       QT+QZ-.-.QN
                      A           N
      where

      0. = Average flow  rate  in mL/minute.
      Q,, Qp,...QN= Flow rates determined at the
                     beginning, end, and intermediate
                     points during  sampling.
      N = Number of points  averaged.
10.9  The total flow is  then  calculated  using the following
      equation:
                              1000
                      Vm= Total  volume  sampled  in  liters at measured
                           temperature and  pressure
                      Tp = Stop time
                      T-| = Start  time  (To-T-,  given  in minutes)

-------
                                T05-8

11.     Sample Analysis

       11.1   Sample Preparation

             11.1.1  The samples  are  returned  to  the  laboratory  in
                     50 ml  screw-capped  glass  vials.   To  recover the
                     DNPH derivatives  the  following procedure  is em-
                     ployed.
             11.1.2  The vials  are  shaken  in a  horizontal  position  on
                     a  reciprocating  shaker for 10 minutes.  The vials
                     are then removed  from the  shaker and  the  isooctane
                     layer  is removed  and  placed  in a second clean  50 ml
                     screw-capped glass  vial using a  disposable  pipette.
             11.1.3  The remaining  aqueous layer  is extracted  with  10 ml
                     of 70/30 (V/V) hexane/methylene  chloride  in the
                     same manner  as described  in  11.1.2.   The  organic
                     layer  is removed  and  combined with the isooctane
                     extract.
             11.1.4  The combined organic  extracts are then concentrated
                     to dryness at  40°C  under  a steam of  pure  nitrogen.
                     When the sample  just  reaches dryness  the  vial  is
                     removed  from the  nitrogen  stream and a measured
                     volume (2-5  ml) of methanol is added to the vial.
                     The  vial is  tightly capped and stored refrigerated
                     until analysis.

       11.2   HPLC  Analysis

             11.2.1  The instrument is assembled and  calibrated  as  described
                     in Section 12.   Prior to each analysis the  detector
                     baseline is  checked to ensure stable operation.
             11.2.2  A  5-25 U.L  aliquot of  the  sample,  dissolved  in
                     methanol,is  drawn into a  clean HPLC  injection  syringe.
                     The sample injection  loop  is loaded  and an  injection
                     is made.   The  data  system, if available,  is activated
                     simultaneously with the injection and the point of
                     injection  is marked on the stripchart recorder.

-------
                              T05-9
             11.2.3   After approximately one minute,  the injection valve
                      is returned to "load" position and the syringe and
                      valve are flushed with methanol  in preparation for
                      the next sample analysis.
             11.2.4   After elution of the last  component of interest the
                      acquisition is terminated  and  the  component concen-
                      trations are calculated as described in Section 13.
             11.2.5   After a stable baseline is achieved the system can
                      be used for further sample analyses as described above.
             11.2.6   If the concentration of a  component exceeds the linear
                      range of the instrument the sample should  be  diluted
                      with methanol, or a smaller volume can be  injected
                      onto the HPLC.

12.     HPLC Assembly and Calibration

       12.1  The HPLC system is assembled as shown in  Figure 3.  The
             typical  chromatographic performance and operating para-
             meters are shown in Figure 4.
       12.2  Mobile phase is prepared by mixing  800  mL of methanol  and
             200 mL of reagent water.   This mixture  is filtered  through
             a 0.22 ym polyester membrane filter in  an all  glass and
             teflon suction filtration apparatus.  The filtered  mobile
             phase  is degassed by purging with helium  gas for 10-15
             minutes  (^ 100 mL/minute) or by heating to  'v60°C for 5-10
             minutes  in an Erlenmeyer flask covered  with a  watch glass.  A
             constant back pressure restrictor (^ 50 psi) or short  length
             (6-12  inches) of 0.01  inch I.D.  teflon  tubing  should be
             placed after the detector to further eliminate mobile  phase
             outgassing.
       12.3  The mobile phase is placed in  the HPLC  solvent reservoir  and
             the pump flow is set at 1  mL/minute and allowed to  pump
             for 20-30 minutes prior to the first analysis.   The detector
             is switched on at least 30 minutes  prior  to the first
             analysis and the detector output is displayed  on a  stripchart
             recorder or similar output device at a  sensitivity  of  .008

-------
                        T05-10

      absorbance units full  scale (AUFS).   Once  a  stable  baseline
      is achieved the system is  ready for  calibration.
12.4  Calibration standards  are  prepared in methanol  from the
      solid DNPH derivatives.   Individual  stock  solutions of
      ^ 100 mg/L are prepared  by dissolving 10 mg  of  the  solid
      derivative in 100 mL of  methanol.  These individual  solutions
      are used to prepare calibration standards  containing all  of
      the derivatives of interest at  concentrations of  0.1  - 10 mg/L,
      which spans the concentration of interest  for most  ambient
      air work.
12.5  All calibration runs are performed as described for sample
      analyses in Section 11.   Before initial use  the operator
      should inject a series of  calibration standards (at least
      three levels) spanning the concentration range  of interest.
      Using the  UV detector,  a  linear  response range of  approximately
      0.1 to 10  mg/L should  be achieved, for ^ 10  pL  injection
      volumes.  Linear response  is indicated where a  correlation
      coefficient of a least 0.999 for a linear  least squares
      fit of the data (concentration  versus area response)  is
      obtained.
12.6  Once linear response has been documented an  intermediate
      concentration standard near the anticipated  levels  for each
      component, but at least  10 times the detection  limit, should
      be chosen  for daily calibration. The response  for  the various
      DNPH components should be  within 10% day to  day.  If greater
      variability is observed  more frequent calibration may be
      required to ensure that  valid results are  obtained.
12.7  The response for each  component in the daily calibration
      standard is used to calculate a response factor according
      to the following equation:
                        cc x v
                RF  =	
                  \*
                          Rc

-------
                              T05-11
             where
                       RF  = response factor for the component of
                             interest in nanograms injected/response
                             unit (usually area  counts).
                       C   = concentration of component in the daily
                        t*
                             calibration standard (mg/L).
                       Vj  = volume of calibration standard injected (yL)
                       R   = response for component of interest in
                             calibration standard (area counts).
13.
Calculations
       13.1   The volume of air sampled is often reported uncorrected for
             atmospheric conditions (i.e.  under ambient conditions).
             However,  the value can be adjusted to  standard  conditions
             (25°C and 760 mm pressure) using  the following  equation:
                                          P.        298
                                  Vs= Vm x -£  x
                                         760     273 + T,
             where
                      Vs = total sample volume at 25°C and 760 mm Hg
                           pressure (liters).
                      Vm = total sample volume under ambient conditions
                           (liters).  Calculated in 10.9 or from dry gas
                           meter reading.
                      P/\ = ambient pressure (mmHg).
                      TA = ambient temperature (°C).

      13.2  The concentration of each aldehyde (as the DNPH derivative is
            calculated for each sample using the following equation:

-------
                       T05-12

                  W .  =  RF,,  X R .  X —
                   d      C     d
      where

               W,  =  total  quantity  of  derivative  in  the  sample
               RF  =  response  factor  calculated  in  12.7
               R,  =  response  for  component  in sample  extract
                     (area  counts  or  other response units).
               Vr  =  final  volume  of  sample  extract (ml).
               Vj  =  volume of extract  injected  onto the  HPLC
                     system (ML).
13.3  The concentration  of  aldehyde  in  the original  sample is
      calculated from the  following  equation:
                         W ,          MW,,
                 C = - 9 - x  —2-   X  1000
      where
               CA =  concentration  of aldehyde  in  the  original
                    sample (ng/L).
               V^  or V$   are  as  specified  in Section  13.1.
               MW. and MWd are  the molecular weights  (g/mole)  of
               the aldehyde and  its corresponding DNPH  derivative,
               respectively.
13.4  The aldehyde concentrations  can be converted to ppbv  using
      the following  equation:
                                        24.4
                  C(ppbv) =  C.(ng/L) X -
      where
               C«(ng/L) is calculated using Vs.

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                                 T05-13

14.     Performance Criteria and Quality Assurance

       This section summarizes the quality assurance (QA)  measures  and
       provides guidance concerning performance  criteria which  should
       be achieved within each laboratory.

       14.1  Standard Operating Procedures (SOPs).

             14.1.1   Each user should generate  SOPs describing the
                      following activities as  accomplished in their
                      laboratory:   1)  assembly,  calibration  and operation
                      of the sampling  system,  2)  preparation, purification,
                      storage and  handling of  DNPH  reagent and  samples,  3)
                      assembly, calibration and  operation  of the HPLC
                      system, and  4) all  aspects  of data recording  and
                      processing.
             14.1.2   SOPs should  provide specific  stepwise  instructions
                      and should be readily available to,  and understood
                      by, the laboratory personnel  conducting the work.

       14.2  HPLC System Performance

             14.2.1   The general  appearance of  the HPLC chromatograph
                      should be similar to that  shown in Figure 4.
             14.2.2   The HPLC system  efficiency and peak  asymmetry
                      factor should be determined in the following  manner.
                      A solution of the formaldehyde DNPH  derivative cor-
                      responding to at least 20  times the  detection
                      limit should be  injected with the recorder chart
                      sensitivity  and  speed set  to  yield a peak
                      approximately 75% of full  scale and  1  cm  wide at
                      half height.   The peak asymmetry factor is determined
                      as shown in  Figure 5, and  should be  between
                      0.8 and 1.8.

-------
                        T05-14

      14.2.3   HPLC system efficiency is calculated according to
               the following equation:
                    N = 5.54
               where
                    N = column efficiency,  theoretical  plates
                    tr= retention time of components (seconds)
                    W-j/2 = width of component peak at half height
                        (seconds)
               A column efficiency of >5,000 should be  obtained.
      14.2.4   Precision of response for replicate HPLC injections
               should be ± 10% or less,  day to day, for calibration
               standards.   Precision of retention  times should  be
               ± 2%, on a  given day.
14.3  Process Blanks

      14.3.1    Prior to use a  10 ml  aliquot  of  each  batch  of DNPH
               reagent should  be analyzed  as described  in  Section
               11.   In general,formaldehyde  levels equivalent to
               >5 ng/L in a 60 liter sample  should be achieved
               and  other aldehyde levels should be <1 ng/L.
      14.3.2    At least one field blank  should  be shipped  and
               analyzed with each group  of samples.  The field
               blank is treated identically  to  the samples except
               that no air is  drawn  through  the reagent.   The
               same performance criteria described in 14.3.1
               should be met for process blanks.

-------
                         T05-15
14.4  Method Precision and Accuracy

      14.4.1   Analysis of replicate samples indicates  a  pre-
               cision of + 15-20% relative standard  deviation
               can be readily achieved.   Each laboratory  should
               collect parallel samples  periodically (at  least one
               for each batch of samples)  to document their
               precision in conducting the method.
      14.4.2   Precision for replicate HPLC injections  should
               be + 10% or better, day to  day, for calibration
               standards.
      14.4.3   Method accuracy is difficult to assess because of
               the difficulty in generating accurate gaseous
               standards.   Literature results indicate  (1-3)
               recoveries  of 75% or greater are achieved  for a
               broad range of aldehydes.   Each laboratory should
               periodically collect field  samples wherein the
               impinger solution is spiked with a known quantity
               of the compound of interest, prepared as a dilute
               methanol solution.  Formaldehyde cannot  be spiked
               in this manner and therefore a solution  of the DNPH
               derivative  should be used  for spiking purposes.
       14.4.4    Before  initial  use  of  the  method each laboratory
                should  generate  triplicate  spiked samples at a minimum
                of three concentration levels,  bracketing  the
                range of interest for  each  compound.   Triplicate
                nonspiked  samples  must also  be  processed.    Recover-
                ies  of  >70  +  20%  and blank  levels of  <5 ng/L for
                formaldehyde  and  1  ng/L for  the other compounds
                (assuming  a 60  liter air sample) should be  achieved.

-------
                               T05-16


                             References

(1)   Grosjean,  D.,  Fung,  K.,  and  Atkinson,  R.,  "Measurements  of
     Aldehydes  in  the Air Environment",  Proc. Air  Poll.  Cont.
     Assoc.,  Paper  80-50.4,  1980.

(2)   Grosjean,  D.  and Fung K.,  "Collection  Efficiencies  of  Cartridges
     and Micro-Impingers  for  Sampling  of Aldehydes in  Air as  2,4-
     Dinitrophenylhydrazones",  Anal. Chem.  54,  1221-1224, 1982.

(3)   Grosjean,  D.,  "Formaldehyde  and Other  Carbonyls  in  Los Angeles
     Ambient  Air",  Environ.  Sci.  Techno!. J_6, 254-262,  1982.

(4)   Riggin,  R.  M.,  "Technical  Assistance Document for Sampling  and
     Analysis of Toxic Organic  Compounds in Ambient Air", EPA-600/4-83-027.
     U.S.  Environmental  Protection  Agency,  Research Triangle  Park,
     North Carolina, 1983.

(5)   Annual  Book of  ASTM  Standards, Part 11.03,  "Atmospheric  Analysis",
     American Society for Testing and  Material,  Philadelphia,
     Pennsylvania,  1983.

(6)   Berry,  D.  A.,  Holdren,  M.  W.,  Lyon, T.  F.,  Riggin,  R.  M., and
     Spicer,  C.  W.,  "Turbine  Engine Exhaust Hydrocarbon  Analysis-Interim
     Report  on  Task  1 and 2",  Report on  Contract No.  F-08635-82-C-0131,
     Air Force  Engineering and  Services  Center,  Tyndall  AFB,  Florida,
     1983.

(7)   Shiner,  R., Fuson,  R.,  and Curtin,  D.,  "The Systematic Identification
     of Organic Compounds",  John  Wiley and  Sons, Inc.,  5th  ed. ,  New
     York, 1964.

(8)   "Method  6  Determination  of SOg Emissions from Stationary Sources",
      Federal Register,  Vol.  42., No.  160,  August  1977.

-------
                                   T05-17
   TABLE 1.   ALDEHYDES AND KETONES FOR WHICH THE METHOD HAS BEEN  EVALUATED
Compound
Formaldehyde
Acetaldehyde
Acrolein
Propanal
Acetone
Crotonaldehyde
Isobutyraldehyde
Methyl Ethyl Ketone
Benzaldehyde
Pentanal
o-Tolualdehyde
m-Tolualdehyde
p-Tolualdehyde
Hexanal
Molecular
Derivative
210
224
236
238
238
250
252
252
286
266
300
300
300
280
Weight
Compound
30
44
56
58
58
70
72
72
106
86
120
120
120
100
Typical
Relative
Retention
1.0
1.3
1.6
1.7
1.9(b)
2.3
2.4
2.8
3.2
3.7
4.8
5.1
5.3
5.7
(a)   Using HPLC conditions shown  in  Figure  4.
     Formaldehyde =1.0

(b)   Acetone background levels in the  reagent  prevent its  determination
     in most cases.

-------
                                                                             Silica Gel
                             Rotometer
Vent
 Dry
 Test
Meter
                                            v
                                           Needle
                                            Valve
                                                               Pump
                                                                                                   Sample Impinger	-,
                                                                                                   (DNPH Reagent)   /
                                                                                                                              O
                                                                                                                              in
                                                                                                                               i
                                                                                                                              C»
                                                    FIGURE 1.  TYPICAL SAMPLING SYSTEM

-------
                                         T05-19
                                SAMPLING DATA SHEET
                            (One Sample Per Data Sheet)
PROJECT:

SITE:
                      DATE(S) SAMPLED:
LOCATION:
                      TIME PERIOD SAMPLED:,

                      OPERATOR:
INSTRUMENT MODEL NO:

PUMP SERIAL NO:	

SAMPLING DATA
                      CALIBRATED BY:
                        Sample  Number:

                 Start Time:
                       Stop Time:
Time
1.
2.
3.
4.
N.
Dry Gas
Meter
Reading





Rotameter
Reading





Flow
Rate,*Q
ml /Min





Ambient
Temperature
°C





Barometric
Pressure,
mmHg





Relative
Humidity, %





Comments





   Total Volume Data**
           Vm = (Final  - Initial)  Dry Gas Meter Reading,  or
                         + Q3---Q.N
                  1
Liters

Liters
N
                                     1000 x (Sampling Time in  Minutes)
     * Flowrate from rotameter or soap bubble calibrator
       (specify which).
    ** Use data from dry gas meter if available.
                      FIGURE 2.  EXAMPLE SAMPLING DATA SHEET

-------
                       INJECTION
                         VALVE
                                       COLUMN
 MOBILE
 PHASE
RESERVOIR
VARIABLE
WAVELENGTH
UV
DETECTOR


• •
DATA
SYSTEM

                                                                                       o
                                                                                       en
                                                                                       ro
                                                                                       o
•

I
STRIPCHART
 RECORDER
                          FIGURE 3 TYPICAL HPLC SYSTEM

-------





































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. ll II -_ ^

i r~r i
a
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i i i i
0 4
c
CD 0)
-So ^,
!>N ^- -£•
^ 0 
CO -c-
o +•* *"
"(O +-> O "^ <1)
C 0
o <.
•r— «
Q.
o
L-
Q-

i
(
I

i
Uv,
^o^o §
c . ^ c
| « 1 i
1 *° -c
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c .-
, QJ 0
Q. >,
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1 I 1 I I 1 \ I I I I 1 ^ 1 I 1 ' 1 ' I ' 1 ' ! I 	 1 ! 1 	 1 | I 	 ' T I J t 1 1 I '
0 60 80 10 0 c' 0 14 0 160 18 0 20 0
                                                                    o
                                                                    en
                                                                     i
                                                                    ro
FIGURE 4.   TYPICAL HPLC CHROMATOGRAM

           Column  -  Zorbax  ODS,  250  x  4.6 mm
           Mobile  Phase  - 80/20  Methanol/^O
           Flow  Rate  - 1 rnL/Minuto
           Detector  - UV at  370  nm

-------
              T05-22
         Asymmetry Factor •
BC
AB
Exempt* Calculation:
     Paak Height - OE - 100 mm
     10% Paak Height - BD - 10 mm
     Peak Width at 10% Peak Height - AC - 23 mm
         AB "11 mm
         BC * 12 mm
     Therefore: Asymmetry Factor » — - 1.1
 FIGURE 8. PEAK ASYMMETRY CALCULATION

-------
                         APPENDIX A—EPA METHOD 608
svEPA
                            United States
                            Environmental Protection
                            Agency
                            Environmental Monitoring and
                            Support Laboratory
                            Cincinnati OH 45268
                            Research and Development
Test Method
                            Organochlorine  Pesticides
                            and PCBs  —  Method 608
                            1.  Scope and Application

                            1.1 This method covers the
                            determination of certain organochlorine
                            pesticides and PCBs. The following
                            parameters can be determined by this
                            method:
                           Parameter
                        STORET No.
CAS No.
Aldrin
o-BHC
/J-BHC
d-BHC
y-BHC
Chlordane
4,4 '-ODD
4, 4 '-DDE
4,4 '-DDT
Dieldrin
Endosulfan I
Endosulfan II
Endosulfan sulfate
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Toxaphene
PCB-1016
PCB-1221
PCB-1232
PCB-1242
PCB-1248
PC B- 12 54
PCB-1260
39330
39337
39338
34259
39340
39350
39310
39320
39300
39380
34361
34356
34351
39390
34366
39410
39420
39400
34671
39488
39492
39496
39500
39504
39508
309-00-2
319-84-6
319-85-7
319-86-8
58-89-9
57-74-9
72-54-8
72-55-9
50-29-3
60-57-1
959-98-8
33212-65-9
1031-07-8
72-20-8
7421-93-4
76-44-8
1024-57-3
8001-35-2
12674-11-2
11104-28-2
11141-16-5
53469-21-9
12672-29-6
11097-69-1
11096-82-5
                           1.2  This is a gas chromatographic
                           (GO method applicable to the determi-
                           nation of the compounds listed above
                           in municipal and industrial discharges
                           as provided under 40 CFR 136.1.
                           When this method is used to analyze
                           unfamiliar samples for any or all of the
                           compounds above, compound identifi-
                           cations should be supported by at least
                           one additional qualitative technique.
                           This method describes analytical
                           conditions for a second gas
                           chromatographic column that can be
                           used to confirm measurements made
                           with the primary column. Method 625
                           provides gas chromatograph/mass
                           spectrometer (GC/MS) conditions
                           appropriate for the qualitative and
                           608-1
                   July 1982

-------
 quantitative confirmation of results for
 all of the parameters listed above,
 using the extract produced  by this
 method

 1.3   The method detection limit (MDL,
 defined in Section 14.1 (in for each
 parameter is listed in Table  1 . The MDL
 for a specific wastewater may differ
 from those listed, depending upon the
 nature of interferences in the sample
 matrix.

 1.4   The sample extraction and
 concentration steps in this method are
 essentially the same as in methods
 606, 609, 611  and 61 2. Thus, a
 single sample may be extracted to
 measure the parameters included in the
 scope of each of these methods. When
 cleanup is required, the concentration
 levels must be high enough to permit
 selection of aliquots as necessary to
 apply appropriate cleanup procedures.
 The  analyst is allowed the latitude to
 select gas chromatographic conditions
 appropriate for the simultaneous
 measurement of combinations of these
 parameters.

 1.5   Any modification of this method,
 beyond those expressly permitted,
 shall be considered as major
 modifications subject  to application
 and  approval of alternate test
 procedures under 40 CFR 1 36.4 and
 136.5.

 1.6   This method is restricted to use
 by or under the supervision of analysts
 experienced in the use of gas chroma-
 tography and in the interpretation of
 gas chromatograms.  Each analyst must
 demonstrate the ability to generate
 acceptable results with this method
 using the procedure described in
 Section 8.2.


 2.   Summary of Me'thod

 2.1  A measured volume of sample,
 approximately one-liter, is solvent
 extracted with methylene chloride
 using a separatory funnel. The
 methylene chloride extract is dried and
 exchanged to hexane, during
concentration to a final volume of 10
 ml or less. Gas chromatographic
conditions are described which permit
the separation and measurement of the
parameters in the extract by electron
capture GC(2>.

 2.2   The method provides a Flonsil
 column procedure and elemental sulfur
 removal procedure to aid in the
 elimination of interferences that may
 be encountered.
 3.   Interferences
 3.1   Method interferences may be
 caused by contaminants in solvents,
 reagents, glassware, and other sample
 processing hardware that lead to
 discrete artifacts and/or elevated
 baselines in gas chromatograms. All of
 these materials must be routinely
 demonstrated to be free from inter-
 ferences under  the conditions of the
 analysis by running laboratory reagent
 blanks as described in Section 8 5.

 3.1.1   Glassware must be scrupulously
 cleaned'31. Clean all glassware as soon
 as possible after use by rinsing with the
 last solvent used in it  This should be
 followed by detergent washing with
 hot water, and  rinses with tap water
 and distilled water.  It should then be
 drained dry and heated in a muffle
 furnace at 400  °C for  1 5 to 30
 minutes Some  thermally stable
 materials, such  as PCBs, may not be
 eliminated by this treatment. Solvent
 rinses with acetone and pesticide
 quality hexane may be  substituted for
 the muffle furnace heating. Thorough
 rinsing with such solvents usually
 elmmates PCB interference. Volumetric
 ware should not be  heated in a muffle
 furnace. After drying and cooling,
 glassware should be sealed and stored
 in a clean environment  to prevent any
 accumulation of dust or other
 contaminants Store inverted or capped
 with aluminum foil
 3.1.2   The use of high purity reagents
 and solvents helps to minimize
 interference problems. Purification of
 solvents by distillation in all-glass
 systems may be required.
 3.2   Interferences by  phthalate esters
 can pose a major problem in pesticide
 analysis when using the elution capture
 detector. These compounds generally
 appear in the chromatogram as large
 elutmg peaks, especially in the 1 5 and
 50% fractions from Florisil. Common
 flexible plastics  contain varying
 amounts of phthalates. These phtha-
 lates are easily extracted or leached
from such materials during laboratory
 operations. Cross contamination of
 clean glassware routinely occurs when
 plastics are handled during extraction
 steps, especially when solvent wetted
 surfaces are handled. Interferences
from phthalates can best be minimized
 by avoiding the  use  of  plastics in the
 laboratory. Exhaustive cleanup of
 reagents and glassware may  be
required to eliminate background
phthalate contamination!4.5). The
 interferences from phthalate esters can
be avoided by using a microcoulometric
or electrolytic conductivity detector.
 3.3  Matrix interferences may be
 caused by contaminants that are
 coextracted from the sample The
 extent of matrix interferences will vary
 considerably from source to source,
 depending upon the nature and
 diversity of the industrial complex or
 municipality being sampled. The
 cleanup procedures in Section 1 1 can
 be used to overcome many of these
 interferences,  but unique samples may
 require  additional cleanup approaches
 to achieve the MDL listed in Table 1.

 4.  Safety

 4.1   The toxicity or carcinogenicity of
 each reagent used in this method has
 not been precisely defined; however,
 each chemical compound should be
 treated as a potential health hazard.
 From this viewpoint, exposure to these
 chemicals must be reduced to the
 lowest possible level by whatever
 means available. The laboratory is
 responsible for maintaining a current
 awareness file of OSHA regulations
 regarding the safe handling of the
 chemicals specified  in this method. A
 reference file of material data handling
 sheets should also be made available to
 all personnel involved in the chemical
 analysis. Additional  references to
 laboratory safety are available and
 have been identified16'81 for the
 information of the analyst.

 4.2   The following  parameters
 covered by this method have been
 tentatively classified as known or
 suspected, human or mammalian
 carcinogens: 4,4'-DDT,4,4'-DDD, the
 BHCs, and the PCBs. Primary
 standards of these toxic compounds
 should be prepared in a hood.

5.   Apparatus and Materials

5.1  Sampling equipment, for discrete
or composite sampling.

5.1.1   Grab sample bottle —Amber
glass, one-liter or one-quart volume,
fitted with screw caps lined with
Teflon. Foil may be substituted for
Teflon if the sample  is not corrosive. If
amber bottles are not available, protect
samples from light. The container must
be washed, rinsed with acetone or
methylene chloride, and dried before
use to minimize contamination.

5.1.2   Automatic sampler (optional) —
Must incorporate glass sample
containers for the collection of a mini-
mum of 250 mL. Sample containers
must be kept refrigerated at 4 °C and
protected  from light during compositing.
If the sampler uses a peristaltic pump,
a minimum length of compressible
                                      608 2
                                                                  July 1982

-------
 silicons rubber tubing may be used.
 Before use, however, the compressible
 tubing should be thoroughly rinsed
 with methanol, followed by repeated
 rinsings with distilled water to minimize
 the potential for contamination of the
 sample. An integrating flow meter is
 required to collect flow proportional
 composites.

 5.2   Glassware (All specifications are
 suggested. Catalog numbers are
 included for illustration only).

 5.2.1   Separatory funnel- 2000-mL,
 with Teflon stopcock.

 5.2.2  Drying column —Chroma-
 tographic column approximately 400
 mm long  x  1 9 mm ID, with coarse frit.

 5.2.3  Chromatographic column —
 Pyrex, 400 mm long x 22 mm ID,
 with coarse fritted plate and Teflon
 stopcock  (Kontes K-42054 or
 equivalent).

 5.2.4  Concentrator tube, Kuderna-
 Danish— 10-mL, graduated (Kontes K-
 570050-1 025 or equivalent).  Calibra-
 tion must be  checked at the volumes
 employed in the test. Ground glass
 stopper is used to prevent evaporation
 of extracts.

 5.2.5  Evaporative flask, Kuderna-
 Danish- 500-mL (Kontes K-570001 -
 0500 or equivalent). Attach to
 concentrator tube with springs.

 5.2.6  Snyder column, Kuderna-
 Danish —three-ball macro (Kontes
 K-503000-0121 or equivalent).

 5.2.7  Vials-Amber glass, 10-to
 1 5-ml capacity, with Teflon-lined
 screw cap.

 5.3   Boiling  chips —approximately
 10/40 mesh. Heat to 400 °C for  30
 minutes or Soxhlet extract with
 methylene chloride.

 5.4   Water bath-Heated, with
 concentric ring cover, capable of
 temperature control ( ± 2 °C). The bath
 should be used in a hood.

 5.5  Balance —Analytical, capable of
accurately weighing 0.0001  g.

 5.6  Gas  chromatograph — An
analytical system  complete with gas
chromatograph suitable for on-column
injection and all required accessories
including syringes, analytical columns,
gases, detector, and strip-chart
recorder. A data system is
recommended for measuring peak
areas.

5.5.1  Column 1  — 1.8 m long  x 4
mm ID glass,  packed with 1.5%
 SP-2250/1.95% SP-2401  on
 Supelcoport (100/1 20 mesh) or
 equivalent. Column 1 was used to
 develop the method performance
 statements in Section 14. Guidelines
 for the use of alternate column
 packings are  provided in Section 12.1.

 5.6.2  Column 2-1 .8 m long x 4
 mm ID glass, packed with 3% OV-1  on
 Supelcoport (100/120 meshl or
 equivalent.

 5.6.3  Detector—Electron  capture.
 This detector has proven effective in
 the analysis of wastewaters for the
 parameters listed in the scope, and
 was used to develop the method
 performance  statements in  Section  14.
 Guidelines for the use of alternate
 detectors are provided  in Section 12.1.

 6.   Reagents

 6.1   Reagent water —Reagent water is
 defined as a water in which  an mter-
 ferent is not observed atthe MDL of
 each parameter of interest.

 6.2  Sodium hydroxide solution (1 0
 N)-(ACS). Dissolve 40g NaOH in
 reagent water and dilute to  1 00 ml.

 6.3  Sodium thiosulfate-(ACS).
 Granular
 6.4  Sulfuric acid solution (1 + 1 ) —
 (ACS). Slowly, add 50  mL H2S04 (sp.
 gr. 1.84) to 50 mL of reagent water.

 6.5   Acetone, hexane, isooctane
 (2,2,4-trimethylpentane), methylene
 chloride —Pesticide quality or
 equivalent.
 6.6   Ethyl ether—Pesticide quality or
 equivalent, redistilled in glass if
 necessary.
 5.5.1  Must  be free of peroxides as
 indicated by EM Laboratories Quant
 test strips (Available from Scientific
 Products Co., Cat. No. P1 1 26-8,  and
 others suppliers.)
 6.6.2  Procedures recommended for
 removal of peroxides are provided with
 the test strips. After cleanup, 20 mL
 ethyl alcohol preservative must be
 added to each liter of ether.

 6.7   Sodium sulfate—(ACS) Granular,
 anhydrous. Purify by heating at 400 °C
 for 4 hours in a shallow tray.

 6.8  Florisil-PR grade (60/100
 mesh); purchase activated at 1 250 °F
 and store in dark in glass containers
 with glass stoppers or foil-lined screw
 caps. Before use, activate each batch
at least 1 6 hours at 1 30 °C  in  a foil
covered glass container.

6.9  Mercury —Triple distilled.
 6.10  Copper powder—Activated.

 6.11  Stock standard solutions (1.00
 ^g/^D — Stock standard solutions can
 be prepared from pure standard
 materials or purchased as certified
 solutions.

 6.11.1  Prepare stock standard
 solutions by accurately weighing about
 0.01 00 grams of pure material
 Dissolve the material in isooctane,
 dilute to volume  in a 1 0-mL volumetric
 flask. Larger volumes can be used at
 the convenience of the analyst. If
 compound purity is certified at 96% or
 greater, the weight can be used
 without correction to calculate the
 concentration of the stock standard.
 Commercially prepared stock standards
 can be used at any concentration if
 they are certified by the manufacturer
 or by an independent source.

 6.11.2  Transfer the stock standard
 solutions into Teflon-sealed screw-cap
 bottles  Store at  4 °C and protect from
 light. Stock standard solutions should
 be checked frequently for signs of
 degradation or evaporation, especially
 just prior to preparing calibration
 standards from them. Quality control
 check standards that can be used to
 determine the accuracy of calibration
 standards will be available from the
 U.S. Environmental Protection Agency,
 Environmental Monitoring and Support
 Laboratory, Cincinnati, Ohio 45268.

 6.11.3  Stock standard solutions
 must be replaced after six months, or
 sooner if comparison with check
 standards indicate a problem.

 7.  Calibration

 7.1   Establish gas Chromatographic
 operating parameters which produce
 retention times equivalent to those
 indicated in Table 1. The gas
 Chromatographic system may be
 calibrated using the external standard
 technique (Section 7.2) or the internal
 standard technique (Section 7.3).

 7.2   External standard calibration
 procedure;

 7.2.1  Prepare calibration standards
 at a minimum of  three concentration
 levels for each parameter of interest by
 adding volumes of one or more stock
 standards to a volumetric flask and
 diluting to volume with isooctane. One
 of the external standards should be at a
 concentration near, but above, the
 MDL and the  other concentrations
 should correspond to the expected
 range of concentrations found in real
samples or should define the working
range of the detector.
                                      608-3
                                                                  July 1982

-------
7.2.2  Using injections of 2 to 5 ^L of
each calibration standard, tabulate
peak height or area responses against
the mass injected. The results can be
used to prepare a calibration curve for
each compound. Alternatively, if the
ratio of response to amount injected
(calibration factor) is a constant over
the working range K10% relative
standard deviation, RSD), linearity
through the origin can be assumed and
the average ratio or calibration factor
can be used in place of a calibration
curve.

7.2.3  The working calibration curve
or calibration factor must be verified on
each working day by the measurement
of one or more calibration standards. If
the response for any parameter varies
from the predicted response by more
than ±10%, the test must be repeated
using a fresh calibration standard.
Alternatively, a new calibration curve
or calibration factor must be prepared
for that compound.

7.3  Internal standard  calibration
procedure. To use this approach, the
analyst must select one or more
internal standards that are similar in
analytical behavior to the compounds
of interest. The analyst must further
demonstrate that the measurement of
the internal standard is not  affected by
method or matrix interferences.
Because of these limitations, no
internal standard can be suggested that
is applicable to  all samples.

7.3.1  Prepare calibration  standards
at a minimum of three concentration
levels for each parameter of interest by
adding volumes of one or more stock
standards to a volumetric flask. To
each calibration standard, add a known
constant amount of one or  more
internal standards, and dilute to volume
with isooctane. One of the  standards
should be at a concentration near, but
above, the MDL and the other concen-
trations should  correspond  to the
expected range of concentrations
found in real samples or should define
the working range of the detector.

7.3.2  Using injections of  2 to 5 ^L of
each calibration standard, tabulate
peak height or area responses against
concentration for each compound and
internal standard, and calculate
response factors (RF) for each
compound using equation 1.

      Eq.  1.  RF = (ASC,S)/(AISCS)
where:
   As  = Response for the parameter to
         be measured.
   A1S  = Response for the internal
         standard.
  Cls  = Concentration of the internal
        standard, (^ig/L).
  Cs  = Concentration of the param-
        eter to be measured, (j/g/L).

  If the RF value over the working
range is a constant «1 0% RSD), the
RF can be assumed to be invariant and
the average RF can be used for
calculations. Alternatively, the results
can be used to plot a calibration curve
of response ratios, AS/A1S, vs. RF.

7.3.3  The working calibration curve
or RF must be verified on each working
day by the measurement of one or
more calibration standards. If the
response for any parameter varies from
the predicted response by more than
± 1 0%, the test must be repeated
using  a fresh calibration standard.
Alternatively, a new calibration curve
must be prepared for that compound.
7.4  The cleanup procedure in Section
11  utilizes Flonsil chromatography.
Florisil from different batches or
sources may vary in absorptive
capacity. To standardize the amount of
Florisil which is used, the use of  lauric
acid value'91 is suggested. The refer-
enced procedure determines the
adsorption from hexane solution of
lauric  acid (mg) per gram Florisil. The
amount of Florisil to be used for each
column is calculated by dividing this
factor into 110 and multiplying by 20
g.
7.5   Before using any cleanup
procedure, the analyst must process a
series of calibration  standards through
the procedure to validate elution
patterns and the absence of interfer-
ences from the reagents.

8.   Quality Control
8.1  Each laboratory that uses this
method is required to operate a formal
quality control program. The minimum
requirements of this program consist of
an initial demonstration of laboratory
capability and the analysis of spiked
samples as a continuing check on
performance. The laboratory is required
to maintain performance records to
define the quality of data that is
generated. Ongoing performance
checks must be compared with
established performance criteria  to
determine if the results of analyses are
within accuracy and precision limits
expected of the method.

8.1.1  Before performing any analyses,
the analyst must demonstrate the
ability to generate acceptable accuracy
and precision with this method. This
ability \s established as described in
Section 8.2.
8.1.2  In recognition of the rapid
advances that are occurring in chroma-
tography, the analyst is permitted
certain options to improve the separa-
tions or lower the cost of measurements.
Each time such modifications are made
to the method, the analyst is required
to repeat the procedure in Section 8 2.

8.1.3  The laboratory must spike and
analyze a minimum of 1 0%  of all
samples to monitor continuing labora-
tory performance. This procedure is
described in Section 8.4.

8.2  To  establish the ability to
generate acceptable accuracy and pre-
cision,  the analyst must perform the
following operations.
8.2.1  Select a representative spike
concentration for each compound to be
measured. Using stock standards,
prepare a quality control check sample
concentrate m acetone 1 000 times
more concentrated than the selected
concentrations. Quality control check
sample concentrates, appropriate for
use with  this method, will be available
from the  U.S. Environmental Protection
Agency,  Environmental Monitoring and
Support Laboratory, Cincinnati, Ohio
45268.
5.2.2  Using a pipet, add 1.00 mL of
the check sample concentrate to each
of a minimum of four 1000-mL aliquots
of reagent water. A representative
wastewater may be used in place of
the reagent water, but one or more
additional aliquots must be analyzed to
determine background levels, and the
spike level must exceed twice the
background level for the test to be
valid. Analyze the aliquots according to
the method beginning in Section  1 0.

8.2.3  Calculate the average percent
recovery, (R), and the standard devia-
tion of the percent recovery (s), for the
results. Wastewater background cor-
rections must be made before R and s
calculations are performed.

8.2.4  Using Table 2, note the
average recovery (X) and standard
deviation (p) expected for each method
parameter. Compare these to the cal-
culated values for R and s. If s >  2p or
|X-R| > 2p, review potential  problem
areas and repeat the test.

5.2.5  The U.S. Environmental Pro-
tection Agency plans to establish
performance criteria for R and s based
upon the results of interlaboratory
testing. When they become available,
these criteria must be met before any
samples  may be analyzed.

8.3 The analyst must calculate
method performance criteria and define
                                       608-4
                            July 1982

-------
 the performance of the laboratory for
 each spike concentration and
 parameter being measured.

 8.3.1  Calculate upper and lower
 control limits for method performance:

  Upper Control Limit (UCU = R  + 3s
  Lower Control Limit (LCD = R  - 3s

 where R and s are calculated as in
 Section 8.2.3. The UCL and LCL can
 be used to construct control charts110'
 that are useful  in observing trends in
 performance. The control limits above
 be replaced by  method performance
 criteria as they become available  from
 the U.S. Environmental Protection
 Agency.

 8.3.2  The laboratory must develop
 and maintain separate accuracy
 statements of laboratory performance
 for wastewater samples. An accuracy
 statement for the method is defined as
 R ± s.  The accuracy statement should
 be developed by the analysis of four
 aliquots of wastewater as described in
 Section 8.2.2,  followed by the calcula-
 tion of  R and s. Alternately, the analyst
 may use four wastewater data points
 gathered through the requirement for
 continuing quality control in Section
 8.4. The accuracy statements should
 be updated regularly! 10>.

 8.4.   The laboratory is required to
 collect  a portion of their samples  in
 duplicate to monitor spike recoveries.
 The frequency of spiked sample analysis
 must be at least 10% of all samples or
 one sample per month, whichever is
 greater. One aliquot of the sample must
 be spiked and analyzed as described in
 Section 8.2. If the recovery for a
 particular parameter does not fall
 within the control limits for method
 performance, the results reported for
 that parameter  in all samples processed
 as part of the same set must be quali-
 fied as described in Section 13.5. The
 laboratory should monitor the frequency
 of data so qualified to ensure that it
 remains at or below 5%.

 8.5 Before processing any samples,
 the analyst should demonstrate through
 the analysis of a one-liter aliquot of
 reagent water, that all glassware and
 reagent interferences are under control.
 Each time a set  of samples is extracted
 or there is a change in reagents, a
 laboratory reagent blank should be
 processed as a safeguard against
 laboratory contamination.

 8.6  It  is recommended that the
 laboratory adopt additional quality
assurance practices for use with this
method. The specific practices that are
most productive depend upon the
 needs of the laboratory and the nature
 of the samples. Field duplicates may be
 analyzed to monitor the precision of
 the sampling technique. When doubt
 exists over the identification of a peak
 on the chromatogram, confirmatory
 techniques such as gas chromatography
 with a dissimilar column, specific
 element detector, or mass spectrometer
 must be used. Whenever possible, the
 laboratory should perform analysis of
 standard reference materials and parti-
 cipate in relevant performance
 evaluation studies.

 9.  Sample Collection,
 Preservation, and Handling

 9.1   Grab samples must be collected
 in glass containers. Conventional
 sampling practices'11 > should be
 followed,  except that the bottle must
 not be prewashed with sample before
 collection. Composite samples should
 be collected in refrigerated glass
 containers in accordance with the
 requirements of the program. Automatic
 sampling equipment must be as free as
 possible of Tygon tubing and other
 potential sources  of contamination.

 9.2  The samples must be iced or
 refrigerated  at 4 °C from the time of
 collection until extraction. If the
 samples will not be extracted within
 72 hours of collection, the sample
 should be adjusted to a pH range of
 5.0 to 9.0 with sodium hydroxide or
 sulfuric acid. Record the volume of acid
 or base used. If aldrin is to be
 determined, add sodium thiosulfate
 when residual chlorine is present. U.S.
 Environmental Protection Agency
 methods 330.4 and 330.5 may be
 used to measure chlorine residual112'.
 Field test kits are available for this
 purpose.

 9.3  All samples  must be extracted
 within  7 days and completely analyzed
 within 40  days of extraction'2'.

 10.   Sample Extraction

 10.1   Mark the water meniscus on the
 side of the sample bottle for later deter-
 mination of sample volume. Pour the
 entire sample into  a two-liter separatory
 funnel.

 10.2   Add 60 mL methylene chloride
 to the sample bottle, seal, and shake
 30 seconds to  rinse the inner surface.
 Transfer the solvent to the separatory
 funnel and extract the sample by
 shaking the funnel for two minutes
 with periodic venting to release excess
 pressure. Allow the organic layer to
 separate from the  water phase for a
minimum of 10 minutes. If the emulsion
interface between layers is more than
 one-third the volume of the solvent
 layer, the analyst must employ me-
 chanical techniques to complete the
 phase separation. The optimum tech-
 nique depends upon the sample, but
 may include stirring, filtration of the
 emulsion through glass wool, centrifu-
 gation, or other physical methods.
 Collect the methylene chloride extract
 in a 250-mL Erlenmeyer flask,

 10.3  Add a second 60-mL volume of
 methylene  chloride to the sample bottle
 and repeat  the extraction procedure a
 second time, combining the extracts in
 the Erlenmeyer flask. Perform a third
 extraction in the same manner.

 10.4  Assemble a Kuderna-Danish
 (K-D) concentrator by attaching a
 10-mL concentrator tube to a 500-mL
 evaporative flask. Other concentration
 devices or techniques may be used  in
 place of the Kuderna Danish if the
 requirements of Section 8.2 are met.

 10.5  Pour the combined extract
 through a drying column containing
 about 1 0 cm of anhydrous sodium
 sulfate, and collect the extract in the
 K-D concentrator. Rinse the Erlenmeyer
 flask and column with 20 to 30 mL of
 methylene chloride to complete the
 quantitative transfer.
 10.6   Add one or two clean boiling
 chips to the evaporative flask and
 attach a three-ball Snyder column.
 Prewet the  Snyder column by adding
 about 1 mL methylene chloride to the
 top. Place the K-D apparatus on a hot
 water bath  (60 to 65 °C) so that the
 concentrator tube is partially immersed
 in the hot water and the entire lower
 rounded surface of the flask is bathed
 with hot vapor. Adjust the vertical
 position of the apparatus and the water
 temperature as required to complete
 the concentration in 1 5 to 20 minutes.
 At the proper rate of distillation the
 balJs of the  column will actively chatter
 but the chambers will not flood with
 condensed solvent. When the apparent
 volume of liquid reaches 1 mL, remove
 the K-D apparatus and allow it to dram
 and cool for at least 1 0 minutes.
 10.7   Increase the temperature of the
 hot water bath to about 80 °C.
 Momentarily remove the Snyder
 column, add 50 mL of hexane and a
 new boiling chip and reattach the
 Snyder column. Prewet the column by
 adding about 1 mL of hexane to the
top. Concentrate the solvent extract as
 before. The elapsed time of concentra-
tion should be 5 to 10 minutes. When
the apparent volume of liquid reaches 1
mL, remove the K-D apparatus and
allow it to drain and cool at least 10
minutes.
                                      608-5
                                                                 July 1982

-------
10.8  Remove the Snyder column and
rinse the flask and its lower joint into
the concentrator tube with 1  to 2 mL
of hexane. A 5-mL syringe is recom-
mended for this operation. Stopper the
concentrator tube and store
refrigerated if further processing will
not be performed immediately. If the
extracts will be stored longer than two
days, they should be transferred to
Teflon-sealed screw-cap bottles. If the
sample extract requires no further
cleanup, proceed with gas chromato-
graphic analysis. If the sample requires
cleanup proceed to Section 1 1.

10.9  Determine the original sample
volume by refilling the sample bottle to
the mark and transferring the liquid to a
1 000-mL graduated cylinder. Record
the sample volume to the nearest 5 mL.

11.   Cleanup and Separation

11.1   Cleanup procedures may not be
necessary for a  relatively clean sample
matrix. The cleanup procedures recom-
mended in this method have been used
for the analysis of various clean waters
and industrial effluents. If particular
circumstances demand the use of an
alternative cleanup procedure, the
analyst must  determine the elution
profile and demonstrate that the
recovery of each compound of interest
is no less than 85%. The Flonsil
column allows for a select fractionation
of the compounds and will eliminate
polar materials.  Elemental sulfur
interferes with the electron capture gas
chromatography of certain pesticides,
but can be removed by the techniques
described below.

11.2  Florisil column cleanup:

11.2.1  Add a weight of Florisil
(nominally 21 g) predetermined by cali-
bration (Section 7.4 and 7.5), to a
chromatographic column. Settle the
Florisil by tapping the column. Add
sodium sulfate to the top of the Florisil
to form a layer 1 to 2 cm deep.  Add 60
mL of hexane to wet  and rinse the
sodium sulfate and Florisil. Just prior to
exposure of the sodium sulfate to air,
stop the elution of the hexane by
closing the stopcock  on the chroma-
tography column. Discard the eluate.

11.2.2  Adjust the sample extract
volume to 10 mL with hexane and
transfer it from the K-D concentrator
tube to the Florisil column. Rinse the
tube twice with 1 to  2 mL hexane,
adding each rinse to the column.

11.2.3  Place a 500-mL K-D flask and
clean concentrator tube under the
chromatography column. Drain the
column into the flask until the sodium
sulfate latyer is nearly exposed. Elute
the column with 200 mL of 6% ethyl
ether in hexane (V/V) (Fraction 1) using
a drip rate of about 5 mL/min. Remove
the K-D flask and set aside for later
concentration. Elute the column again,
using 200 mL of 1 5% ethyl ether in
hexane (V/V)(Fraction 2), into a second
K-D flask. Perform the third elution
using 200 mL of 50% ethyl ether in
hexane (V/V)(Fraction 3). The elution
patterns for the pesticides an PCB's are
shown in Table 2.

11.2.4  Concentrate the eluates by
standard K-D techniques (Section
10.6),  substituting hexane for the
glassware rinses and using the water
bath at about 85 °C. Adjust final
volume to 1 0 mL with hexane. Analyze
by gas chromatography.

11.3   Elemental sulfur will usually
elute entirely in Fraction 1 of the Florisil
column cleanup. To remove sulfur
interference from this fraction or the
original extract, pipet 1.00 mL of the
concentrated extract  into a clean con-
centrator tube or Teflon-sealed vial.
Add one to three drops of mercury and
seal'13), Agitate the contents of the
vial for 1 5 to 30 seconds. Prolonged
shaking (two hours) may be required. If
so, this may be accomplished with a
reciprocal shaker. Alternatively,
activated copper powder may be used
for sulfur removal'141. Analyze by gas
chromatography.

12.   Gas Chromatography

12.1   Table 1 summarizes the
recommended operating conditions for
the gas chromatograph. This table
includes retention times and MDL that
were obtained under these conditions.
Examples of the parameter separations
achieved by column 1 are shown in
Figures 1 to 10. Other packed
columns, chromatographic conditions,
or detectors may be used if the
requirements of Section 8.2 are met.
Capillary  (open-tubular) columns may
also be used if the relative standard
deviations of responses for replicate
injections are demonstrated to be less
than 6%  and the requirements of
Section 8.2 are met.

12.2  Calibrate the system daily as
described in Section 7.

12.3  If the internal standard
approach is being used, the internal
standard must be added to the sample
extract and mixed thoroughly
immediately, before injection into the
instrument.

12.4  Inject 2 to 5/A of the sample
extract using the solvent-flush
technique* 15>. Smaller (1 .0 nD volumes
can be injected if automatic devices are
employed. Record the volume injected
to the nearest 0.05 ^L, the total
extract volume, and the resulting peak
size in area or peak height units.

12.5   The width of the retention time
window used to make identifications
should be based upon measurements
of actual retention time variations of
standards over the course of a day.
Three times the standard deviation of a
retention time for a compound can be
used to calculate a suggested window
size; however, the experience of the
analyst should weigh heavily  in the
interpretation of chromatograms.

12.6   If the response for the peak
exceeds the working  range of the
system, dilute the extract and
reanalyze.

12.7   If the measurement of the peak
response is prevented by the  presence
of interferences, further cleanup is
required.

13.   Calculations

13.1   Determine the concentration of
individual compounds in the sample.

13. 1. 1  If the external standard
calibration procedure is used, calculate
the amount of material injected from
the peak response using  the calibration
curve or calibration factor in Section
7.2.2. The concentration in the sample
can be calculated from equation 2:
Eq. 2. Concentration,
                            (A)(Vt)
                            (V)(V >
where:
  A  =  Amount of material injected, in
        nanograms.
  V, =  Volume of extract injected
  V
       Volume of total extract i
  Vs =  Volume of water extracted
        (mL).

 13.1.2   If the internal standard cali-
bration procedure was used, calculate
the concentration in the sample using
the response factor (RF) determined in
Section  7.3.2 and equation 3.

Eq. 3
                         (A.MI,)
Concentration, Mg/L=   (AIS)(RF)(VO)
where:
  As  = Response for the parameter to
        be measured.
  A1S = Response for the internal
        standard.
  ls  = Amount of internal standard
        added to each extract (fig).
        Volum
        liters.
  V0  = Volume of water extracted, in
                                      608-6
                                                                 July 1982

-------
 13.2   When it is apparent that two or
 more PCS (Aroclor) mixtures are
 present, the Webb and McCall
 procedure'16> may be used to identify
 and quantify the Aroclors.

 13.3   For multicomponent mixtures
 (chlordane, toxaphene  and PCBs)
 match retention times of peaks in the
 standards with peaks in the sample.
 Quantitate every identifiable peak
 unless interference with individual
 peaks persist after cleanup. Add peak
 height or peak area of each identified
 peak in the chromatogram. Calculate
 as total response in the sample versus
 total response in the standard.

 13.4   Report results in micrograms
 per liter without correction for recovery
 data. When duplicate and spiked
 samples are analyzed, report all data
 obtained with the sample results.

 13.5  For samples processed as part
 of a set where the  laboratory spiked
 sample  recovery falls outside of the
 control  limits in Section 8.3,  data for
 the affected parameters must be
 labeled  as suspect.

 14.   Method Performance

 14.1  The method detection limit
 (MDL) is defined as the  minimum
 concentration of a substance that can
 be measured and reported  with 99%
 confidence that the value is above
 zero'1'.  The MDL concentration^ listed
 in Table 1 were obtained using reagent
 water' 17>. Similar results were achieved
 using representative wastewaters.

 14.2 This method has been tested
 for linearity of spike recovery from
 reagent water and has been demon-
 strated to be applicable  over the
 concentration range from 4 x MDL up
 to 1000 x MDL with the following
 exceptions: Chlordane recovery at 4 x
 MDL was low (60%); Toxaphene
 recovery was demonstrated linear over
 the range of 10 x MDL to  1000 x
 MDLH7I.

 14.3 In a single laboratory (South-
 west Research Institute), using spiked
 wastewater samples, the average
 recoveries presented in  Table 3 were
 obtained<4>.-Each spiked sample was
 analyzed in triplicate on  two separate
days. The standard deviation of the
percent  recovery is also included in
Table 3.

 14.4  The U.S. Environmental Protec-
tion Agency is in the process of
conducting an interlaboratory method
study to fully define the performance
of this method.
 References

 1  See Appendix A
 2. "Determination of Pesticides and
 PCBs in Industrial and Municipal
 Wastewaters." Report for EPA
 Contract 68-03-2606 In preparation.
 3. ASTM Annual Book of Standards,
 Part 31, D3694, "Standard Practice
 for Preparation of Sample Containers
 and for Preservation,"  American
 Society for Testing and Materials,
 Philadelphia, PA, p. 678, 1980
 4. Giam, D.S.,  Chan H S. and Nef,
 G.S., "Sensitive Method for
 Determination of Phthalate Ester
 Plasticizers in Open-Ocean Biota
 Samples," Ans/ytica/ Chemistry, 47,
 2225, (1975).
 5. Giam, C.S.,  Chan, H.S , "Control of
 Blanks in the Analysis of Phthslates in
 Air and Ocean Biota Samples," U.S.
 National Bureau of Standards. Special
 Publication 442, pp  701 708,1976.
 6. "Carcinogens—Working With
 Carcinogens,"  Department of Health,
 Education, and Welfare, Public Health
 Service. Center for Disease Control,
 National Institute for Occupational
 Safety1 and Health, Publication No.
 77-206, Aug. 19/7
 7. "OSHA Safety and Health
 Standards, General Industry," (29 CFR
 19101, Occupational Safety and
 Health Administration,  OSHA 2206,
 (Revised, January 1976).
 8. "Safety in Academic Chemistry
 Laboratories," American Chemical
 Society Publication, Committee on
 Chemical Safety, 3rd Edition, 1 979.
 9. Mills,  P.A., "Variation of Flonsil
 Activity: Simple Method for Measuring
 Absorbent Capacity and Its Use in
 Standardizing Florisil  Columns,"
 Journal of the Association of Official
 Analytical Chemists,  51, 29 (1968).
 10. "Handbook for AnalyticafQuality
 Control in Water and Wastewatei
 Laboratories," EPA-600/4-79-019,
 U.S. Environmental Protection Agency,
 Environmental Monitoring and Support
 Laboratory, Cincinnati, Ohio 45268,
 March 1979.
 11. ASTM Annual Book of Standards,
 Part 31, D3370, "Standard Practice
 for Sampling Water," American
 Society for Testing and  Materials,
 Philadelphia, PA. p. 76,  1980.
 1 2. "Methods 330.4 (Titrimetric,
 DPD-FAS) and 330 5 (Spectrophoto-
 metnc, DPD) for Chlorine, Total
 Residual," Methods for Chemical
 Analysis of Water and Wastes, EPA
 600-4/79-020, U S Environmental
 Protection Agency, Environmental
 Monitoring and Suppoit  Laboratory,
Cincinnati, Ohio 45268, March 1979.
 1 3. Goerlitz, D.F. and Law, L.M.,
Bulletin for Environmental
Contamination and Toxicology,  6 9
(1971).
 1 4. "Manual of Analytical Methods for
the Analysis of Pesticides in Human
Environmental Samples," U.S. Environ-
mental Protection Agency, Health
Effects Research Laboratory, Research
Triangle Park, N.C., EPA Report
600/8-80-038, Section 1 1,B, p.6.
 1 5  Burke, J.A., "Gas Chromatography
for Pesticide Residue Analysis; Some
Practical Aspects," Journal of the
Association of Official Analytical
Chemists, 48, 1037 (1965).
16. Webb, R.G., and McCall, A.C.,
"Quantitative PCB Standards for
Electron Capture Gas
Chromatography," Journal of
Chromatographtc Science, 11, 366
(1973)
1 7. "Method Detection Limit and
Analytical Curve Studies, EPA Methods
606, 607, and 608," Special letter
report for EPA Contract 68-03-2606.
Environmental Monitoring and Support
Laboratory —Cincinnati, Ohio 45268.
                                     608-7
                                                                July 1982

-------
Table 1. Chromatographic Conditions and Method
Detection Limits
Retention Time Method
Table 2. Distribution of Chlorinated Pesticides and PCBs
into Florisil Column Fractions2
Percent Recovery
(min.) Detection Limit
Parameter
a-BHC
Y-BHC
P-BHC
Heptachlor
6-BHC
A Id r in
Hepachlor epoxide
Endosulfan 1
4, 4 '-DDE
Dieldrin
Endrin
4,4'-DDD
Endosulfan II
4, 4 '-DDT
Endrin aldehyde
Endosulfan sulfate
Chlordane
Toxaphene
PCB-1016
PCB-1221
PCB-1232
PCB-1242
PCB-1248
PCB-1254
PCB-1260
Column 1 conditions:
Column 1
1.35
.70
1.90
2.00
2.15
2.40
3.50
4.50
5.13
5.45
6.55
7.83
8.00
9.40
11.82
14.22
mr
mr
mr
mr
mr
mr
mr
mr
mr
Column 2
1.82
2.13
1.97
3.35
2.20
4.10
5.00
6.20
7.15
7.23
8.10
9.08
8.28
11.75
9.30
10.70
mr
mr
mr
mr
mr
mr
mr
mr
mr
W/L
0.003
0.004
0.006
0.003
0.009
0.004
0.083
0.014
0.004
0.002
0.006
0.011
0.004
0.012
0.023
0.066
0.014
0.24
nd
nd
nd
0.065
nd
nd
nd
Suoelcooort 1 1 00/1 20 mesh) coated

Parameter
Aldrin
a-BHC
P-BHC
6-BHC
y-BHC
Chlordane
4, 4 '-ODD
4, 4 '-DDE
4,4 '-DDT
Dieldrin
Endosulfan 1
Endosulfan
Endosulfan sulfate
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Toxaphene
PCB-1016
PCB-1221
PCB-1232
PCB-1242
PCB-1248
PCB-1254
PCB-1260
Fraction
1
100
100
97
98
100
100
99
98
100
0
37
0
0
4
0
100
WO
96
97
97
95
97
103
90
95
by Fraction
Fraction Fraction
2 3









WO
64
7 91
0 106
96
68 26





4




  with 1.5%SP-2250/1.95%SP-2401 packedina 1.8m
  long x  4 mm ID glass column with 5% Methane/95%
  Argon carrier gas at a flow rate of 60 mL/min. Column
  temperature isothermal at 200 °C, except for PCB-1016
  through  PCB-1248,  which  should be measured at
  160°C.
Column 2 conditions: Supe/coport (100/120 mesh) coated
  with 3% OV-1 in a 1.8 m long x 4 mm ID glass column
  with 5% Methane/95% Argon carrier gas at a flow rate of
  60 mL/min.  Column temperature, isothermal at 200 °C,
  for the pesticides;  140°C for PCB-1221 and  1232;
  170°C for PCB-1016 and 1242 to 1268.
mr — Multiple peak response. See Figures 2 thru 10.
nd — Not determined.
Eluant composition by fraction:
Fraction 1 — 6% ethyl ether in hexane
Fraction 2— 15% ethyl ether in hexane
Fraction 3—50% ethyl ether in hexane
                                    608-8
                                                              July 1982

-------
Table 3. Single Operator Accuracy and Precision
Average Standard Spike Number
Percent Deviation Range of Matrix
Parameter Recovery % (\tg/U Analyses Types
Aldrm 89
a-BHC 89
P-BHC 88
6-BHC 86
y-BHC 97
Chlorane 93
4-4' -ODD 92
4, 4 '-DDE 89
4, 4 '-DDT 92
Dieldrin 95
Endosu/fan I 96
Endosulfan II 97
Endosu/fan su/fate 99
Endrin 95
En drm aldeh yde 87
Heptachlor 88
Heptachlor epoxide 93
Toxaphene 95
PCB-1016 94
PCB-1221 96
PCB-1232 88
PCB-1242 92
PCB-1248 90
PCB-1254 92
PCB-1260 91

Column: 1.5%SP-2250+
2.5 2.0 15 3
2.0 1.0 15 3
1.3 2.0 15 3
3.4 2.0 15 3
3.3 1.0 15 3
4.1 20 21 4
1.9 6.0 15 3
2.2 3.0 15 3
3.2 8.0 15 3
2.8 3.0 15 2
2.9 3.0 12 2
2.4 5.0 14 3
4. 115 153
2.1 5.0 12 2
2.1 12 11 2
3.3 1.0 12 2
1.4 2.0 15 3
3.8 200 18 3
1.8 25 12 2
4.2 55-11O 12 2
2.4 110 12 2
2.0 28-56 12 2
1.6 40 12 2
Column: 1.5%SP-2250+
1.95% SP-2401 on
Supelcoport
Temperature: 200°C.
Detector: Electron capture












,

/
I ,

I / VW/^ *• 	
", J y v s — - — ~^^-~__
ty


• i i i i i i i
3.3 40 18 3 0 4 8 12 16
5-5 80 18 3 Retention time minutes
Figure 2. Gas chromatogram
1.95% SP-2401 on Supelcoport ot *™°r°*n*











I

Temperature: 200° C.
Detector: Electron capture
!t o
"* §•
fa0
2l -2 Q K.
^o 5 u. Q Q
 v--v





S
^w
g
c

£
I

ill!
          4          8         12
            Retention time, minutes
Figure 1.  Gas chromatogram of pesticides.
                                      608-9
July 1982

-------
                     Column: 1.5% SP-2250+
                             1.95% SP-2401 on
                             Supelcoport
                     Temperature: 200°C.
                     Detector: Electron capture
   2      6      10      14     18     22
                Retention time, minutes

Figure 3.  Gas chromatogram of toxaphene
   Column: 1.5% SP-2250+ 1.95% SP-2401 on
           Supelcoport
   Temperature:  160°C.
   Detector: Electron capture
 26
    2        6      10      14      18
             Retention time, minutes

Figure 4.  Gas chromatogram of PCB-1016.

                                   608-10
22
                  Column: 1.5% SP-2250+ 1.95% SP-2401 on
                          Supelcoport
                  Temperature: 160°C.
                  Detector: Electron capture
                  2        6      10      14      18
                             Retention time, minutes

               Figure 6.  Gas chromatogram of PCB-1221.
                Column: 1.5% SP-2250+ 1.95% SP-2401 on
                        Supelcoport
                Temperature: 160°C.
                Detector: Electron capture
    22
                 2      6      10      14      18
                           Retention time, minutes

             Figure 6.  Gas chromatogram of PCB-1232.

                  July 1982
22
24

-------
   Column:  1.5% SP-2250+ 1.95% SP-2401 on
           Supelcoport
   Temperature: 160°C.
   Detector: Electron capture
    2       6      10      14      18
              Retention time, minutes

 Figure 7.   Gas chromatogram of PCB-1242.
22
                 Column:  1.5%SP-2250+ 1.95% SP-2401 on
                         Supelcoport
                 Temperature: 200°C.
                 Detector: Electron capture
                                                             2        6        10       14

                                                                        Retention time, minutes

                                                         Figure 9.  Gas chromatogram of PCB-1254.
                                                      18
     22
   Column: 1.5% SP-2250+ 1.95% SP-2401 on
           Supelcoport
   Temperature:  160°C.
   Detector: Electron capture
   2      6      10     14     18     22
            Retention time, minutes

Figure 8.  Gas chromatcgram of PCB-1248.

                                    608-11
  26
                 Column: 1.5% SP-2250+ 1.95% SP-2401 on
                         Supelcoport
                 Temperature: 200°C.
                 Detector: Electron capture
                 2      6     10     14     18    22
                              Retention time, minutes
              Figure 10.  Gas chromatogram of PCB-1260.
26
                                                              July 1982
                                                                               ' U S GOVERNMENT PRINTING OFFICE 1984 759-102/0944

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