&EPA
United States
Environmental Protection
Agency
Office of Chemical Safety
and Pollution Prevention
(7101)
EPA712-C-001
January 2012
       Ecological Effects
       Test Guidelines

       OCSPP 850.6100:
       Environmental
       Chemistry Methods
       and Associated
       Independent
       Laboratory Validation

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                                     NOTICE

     This guideline is one of a series of test guidelines established by the United States
Environmental Protection Agency's Office of Chemical Safety and Pollution Prevention
(OCSPP) for use in testing pesticides and chemical substances to develop data for
submission to the Agency under the Toxic Substances Control Act (TSCA) (15 U.S.C. 2601,
et seq.), the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) (7 U.S.C. 136, et
seq.), and section 408 of the Federal Food, Drug and Cosmetic (FFDCA) (21 U.S.C. 346a).
Prior to April 22, 2010, OCSPP was known as the Office of Prevention, Pesticides and Toxic
Substances (OPPTS). To distinguish these guidelines from guidelines issued by other
organizations, the numbering convention adopted in 1994 specifically included OPPTS as
part of the guideline's number. Any test guidelines developed after April 22, 2010 will use
the new acronym (OCSPP)  in their title.

     The OCSPP harmonized test guidelines serve as a compendium of accepted scientific
methodologies and protocols that are intended to provide data to inform regulatory decisions
under TSCA, FIFRA, and/or FFDCA. This document provides guidance for conducting the
test, and is also  used  by EPA, the public, and the companies that are subject to data
submission requirements under TSCA, FIFRA, and/or the FFDCA.  As a guidance
document, these guidelines are not binding on either EPA or any outside parties, and the
EPA may depart from the guidelines where circumstances warrant and without prior notice.
At places in this  guidance, the Agency uses the word "should."  In this guidance, the use of
"should" with regard to an action means that the action is recommended rather than
mandatory. The procedures contained in this guideline are strongly recommended for
generating the data that are the subject of the guideline, but EPA recognizes that departures
may be appropriate in specific situations. You may propose alternatives to the
recommendations described in these guidelines, and the Agency will assess them for
appropriateness on a  case-by-case basis.

     For additional information about these test guidelines and to access these guidelines
electronically, please go to http://www.epa.qov/ocspp and select "Test Methods &
Guidelines" on the left side navigation menu.  You may also access the guidelines in
http://www.regulations.gov grouped by Series under Docket ID #s: EPA-HQ-OPPT-2009-
0150 through EPA-HQ-OPPT-2009-0159, and EPA-HQ-OPPT-2009-0576.

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OCSPP 850.6100: Environmental chemistry methods and associated independent
laboratory validation.

(a) Scope—

       (1) Applicability. This guideline is intended to be used to help develop data to submit to
       EPA under the Toxic Substances Control Act (TSCA) (15  U.S.C.  2601,  et seq.), the
       Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (7 U.S.C.  136, et seq.), and
       the Federal Food, Drug, and Cosmetic Act (FFDCA) (21 U.S.C. 346a).

       (2) [Reserved]

(b) Purpose. This guideline is intended to  provide guidance on demonstrating the performance
of environmental chemistry methods (ECMs)  used in field  dissipation  and ground  water
monitoring studies under the OCSPP 835 Environmental Fate Test Guidelines, or used in field
studies of terrestrial and aquatic organisms  and plants under the OCSPP 850 Ecological Effects
Test Guidelines.  In addition guidance is provided on the conduct and performance of an ECM's
associated  independent laboratory  validation (ILV).   When reporting  an ECM  and its
performance to the Agency in support of study results, registrants are required under 40 CFR
Part 158 to provide to the Agency an ILV of the ECM(s) used to generate the laboratory and/or
field residue data. An ILV is a part of a process to verify that a submitted ECM is suitable for its
intended purpose and will be able to generate laboratory and/or field residue  data when used
routinely that are accurate and precise at the set reportable residue range. This includes all single
or  multianalyte  methods   for  identification  and  quantification of the  parent  compound,
lexicologically significant metabolites and degradates in each environmental matrix sampled in
the specific guideline study.

(c) General considerations.

       (1) Registrant(s) provide to the Agency a report of a finalized ECM with appropriate
       revisions  or  changes recommended by an independent  laboratory based on their ILV
       along with the laboratory or field residue study results.

       (2) Registrants need to use  an independent laboratory to validate the environmental
       chemistry methods  used to  generate  laboratory and/or  field  residue data.    If  that
       laboratory is located in the registrant's  organization, or is in anyway  associated with the
       development of the original ECM, the same people, equipment, instruments,  and supplies
       (i.e., glassware, solvents,  reagents,  standard reference  materials, etc.) should  not be
       utilized to validate the ECM.  The Agency does not expect the registrant to synthesize or
       purchase  another  lot of authentic  analytical grade standard  but it  does expect the
       independent  laboratory would need to use a new aliquot of that standard to  prepare
       spiking solutions for the ILV in order for the results to be meaningful.

       (3) If the  methods to be used to generate study data use conventional gas chromatography
       (GC), liquid chromatography (LC), etc., confirmatory methods  include using a mass
       spectrometer (MS)  in conjunction with the method (e.g., GC/MS, LC/MS) or a  second
       column or other suitable procedures.  It is not necessary  typically  to perform  another
       confirmatory procedure  where  GC/MS and  LC/MS  methods are used as  the primary

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       method(s) to generate study data.

       (4) Regulatory chemists should be able to validate practical and rapid analytical methods
       using  a set  of samples in twenty-four hours (e.g., three eight-hour working days);
       however, the Agency recognizes that methods may require additional time.

       (5) Performance data submitted  to the  Agency  should demonstrate that  an adequate
       number of samples for each test level were extracted, cleaned up,  and analyzed. Each set
       should have an appropriate number of samples with quality control samples intermingled.
       This  data should  support the limit  of detection (LOD) or the  method detection  limit
       (MDL), the established limit of quantitation (LOQ), and the precision and  accuracy for
       each ECM.

(d) Environmental chemistry method—

       (1) Method Details.

              (i) The ECM should be clearly written with complete analytical methods that
              describe the exact procedure, materials, and equipment in sufficient detail to be
              used by laboratory chemists  to review the ECM and its  associated  ILV results.
              All environmental chemistry methods should be stamped non-confidential.

              (ii) Analytical environmental chemistry methods  used should be practical, and be
              able to quantitate analytes in the study matrix (or  matrices) at the  data  quality
              objective(s) set for the laboratory or field  residue study.  Equipment used to
              perform the method(s) should be commercially available in the United States.

              (iii) The analytical methods should meet  acceptable performance  objectives
              described in paragraph (d)(2) of this guideline.

              (iv) During the Agency evaluation of an ECM  or ECMs, the registrant may be
              requested to supply to the Agency an active ingredient analytical grade standard
              and/or lexicologically significant metabolite(s) and degradate(s) to  the Agency.
              In addition stable derivative(s) that were used to identify and quantitate the target
              analytes may also be requested to support the evaluation of the ECM and ILV by
              the Agency.

       (2) Data quality objectives.

              (i) The mean  recovery at each spiking level, at or above the LOQ,  should lie
              between 70 and  120%  of  the  known quantity  of  the pesticide/metabolite/
              degradate spiked into the matrix blanks during the method validation.

              (ii) The relative standard deviation (RSD) of replicate measurements of recoveries
              should not  exceed the target level of plus or minus 20%.

              (iii) The Agency recognizes  that some  methods may not be able to meet these
              precision objectives.  The Agency will review the results of those methods to


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              determine their significance on the acceptability of the ECM. Methods will not be
              rejected outright for failure to comply with each and every aspect of the data
              quality objectives but will be reviewed on a case-by-case basis to determine their
              suitability by science reviewers and chemists in the Agency.

              (iv) For an acceptable ECM, reported sample values should not be  corrected for
              recoveries.

(e) Independent laboratory validation procedures—

       (1) Independent laboratory.

              (i) Validation of the ECM is conducted by a laboratory operating independently
              from that of the  originator of the method.  The independent laboratory conducting
              the validation may be privately  or publicly owned and under certain conditions
              may belong  to  the same  organization as the originating laboratory  or  in the
              registrant's own organization.

              (ii)  The originating   and validation  laboratories  may  belong to  the same
              organization,  but in  order for  the  validation to be independent  the  analysts,
              equipment, instruments, and supplies (e.g., glassware, solvents, reagents, standard
              reference materials)  should  be distinct  and operate  separately  and without
              collusion for the  validation.    Furthermore,  the personnel  conducting  the
              independent  validation should not report to the same  study  director  who was
              involved in developing the original method or who may have used the method to
              develop data for laboratory field studies  to  support pesticide registration or
              reregi strati on actions.  For  the validation  to  be independent, the  laboratory
              chemists chosen to conduct the ILV would be expected to be unfamiliar with the
              method  both in its  development and subsequent use  in  analyzing samples
              collected from field studies.  These individuals, however, should be trained and
              experienced pesticide residue chemists.

              (iii) ILV trials are conducted under FIFRA GLP (40 CFR Part 160).   Alternatively
              ILV trials conducted  under OECD Principles of Good Laboratory Practice are
              also considered in compliance with FIFRA GLP.

       (2) Test substance.  An aliquot of the test substance used in the method  development
       should be used to prepare spiking solutions for the ILV aliquot of that standard in order to
       prepare spiking solutions for the ILV.

       (3) Test matrix.

              (i) To  assess  the ECM, the ILV test includes normal test conditions which include
              the presence  of other compounds expected to be present. Matrix or matrices (e.g.,
              soil, water, plant or animal tissue) to be sampled as part of the laboratory  and/or
              field study to generate residue data should be identified and/or supplied to the
              independent  lab by the registrant.  Chemists at the independent lab should use
              these samples to prepare matrix spikes for the validation study.

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       (ii) An ILV is conducted for each ECM for a given sample matrix for each parent
       compound, significant metabolites, and/or degradates.  A method used for more
       than  one  study should meet the same  performance standards as the original
       method. For a given sample matrix, the registrant should select the most difficult
       analytical  sample condition from the study (e.g., high organic content versus low
       organic content in  a soil matrix) to analyze from the study to demonstrate how
       well the method performs.

       (iii) It is recommended that the registrant or their representative keep a reasonable
       amount of each solid matrix tested from a site for two years after registration,
       reregi strati on, or until the Agency has completed its evaluation of the studies.

(4) Environmental chemistry methods.

       (i) The ECMs  given to the independent laboratory should be the same ones that
       were used or to be used by the registrant to generate laboratory and/or field study
       residue data.  For the ILV, the laboratory conducting the ILV uses the methods
       exactly as they are written  by the registrant or its method development laboratory
       and should only contact the registrant or developer to clarify minor deficiencies in
       the methods. For example, if the characteristics of the clean up column were not
       adequately described in a method, the  independent laboratory  should contact the
       registrant or developer for clarification  prior to running the first sample set of ILV
       samples (see paragraph (e)(5)(i)(A) of this guideline).

       (ii)  The  laboratory conducting the ILV trial  may contact the developers or
       previous  users of the method prior to running the first set of samples, but all
       communications should be logged and reported to the Agency documenting that
       such communication did not compromise the independent evaluation.  The ILV
       itself is likely to be invalid  if anyone  from the  petitioner,  developer,  or any
       previous users  are allowed to visit the laboratory during the ILV trial to observe,
       offer help, or assist the chemists or technicians.

(5) ILV. The  independent laboratory establishes the relationship between the instrument
responses and  concentrations of analytes and verifies that matrix control  samples are free
of interferences  at the appropriate retention time, wavelength  or detector setting.  All
quality control conditions should be satisfied in order to demonstrate  that the method is
under control and before the independent laboratory analyzes any performance samples
to be reported to  the Agency.  Any contact with the registrant  or developers during the
establishment  of the  method  should be documented in writing  in the final report
submitted by the independent laboratory.  This should be conducted following FIFRA
GLP (40 CFR Part 160) or alternatively conducted following OECD Principles of GLP,
which are considered in compliance with FIFRA GLP.

       (i) Performance samples—

              (A) Sample sets.  A maximum of three sample  sets  are used by an
              independent laboratory to validate  the  method  as written.  A complete
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sample set consists at a minimum of a reagent blank, two unspiked matrix
control  samples,  five matrix  control samples  spiked  at  the  LOQ and
another five matrix  control  samples  spiked  at  ten times  the  LOQ
(lOxLOQ) for each distinct matrix.  A complete set may include more than
thirteen samples depending on the number of reagent, unspiked and spiked
matrix control  samples.   It may  be necessary, however,  to divide  a
complete set into two subsets for efficient handling.  Each subset should
contain a  reagent blank,  two unspiked matrix control samples, and five
matrix control samples spiked  at the  LOQ or  lOxLOQ. The independent
laboratory will  use  the predetermined values from the registrant for the
LOQ and lOxLOQ to establish  appropriate spiking levels.

(B) Validation.

       (1) A successful ILV includes performance data on at least one
       complete set of samples  that meets those data quality  objectives
       described in  paragraph (d)(2) of this guideline.

             (a) Data from matrix control samples (blanks) are not used
             to  correct values  from  spiked  matrix   controls  for
             recoveries.

             (b) Interferences  with peak areas that  are less than 50
             percent (%) at the MDL  or  LOD,  are considered  not
             significant.

       (2) If the performance data on the first set of samples at any of the
       spiking  levels are  unsuccessful,  the independent laboratory may
       contact the registrant  or developer to clarify the directions given in
       the method.  Any contact with the registrant or developers during
       the method validation should be documented in writing in the final
       report submitted by the independent laboratory.

       (3) If the independent laboratory cannot generate performance data
       that is similar to the  registrant's or developer's after running the
       second sample  set, the independent laboratory may contact the
       registrant, developer,  or other  users of the method to further clarify
       the directions given in the method.  All communications should be
       recorded.

       (4) If the independent laboratory cannot generate performance data
       that is similar to the registrant's or developer's after the third set,
       the method  should be  failed and a report  sent to the registrant
       explaining why the method  failed.   The registrant should then
       decide whether to  repeat the  independent laboratory validation at
       another laboratory, further develop the method, or withdraw it.
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                           (5) Any significant changes that are made to the  method by the
                           chemists at the  independent lab  should be incorporated into the
                           original  method and  reported  in writing  immediately to the
                           registrant.  If those changes impact the performance of the original
                           method, such as its precision, accuracy or limit of quantitation, the
                           registrant should report those changes to the Agency. The revised
                           or  rewritten  method,  performance  data,  chromatograms  and
                           computations from all sets and/or subsets are sent to the registrant.
                           The registrant, with the assistance of the IL, will  decide how to
                           present that information to the Agency.

              (ii) ILV report to registrant.  The independent laboratory should prepare a well
              documented laboratory report and send it to the registrant as the ILV of the ECM
              and that report with appropriate changes by the registrant is then submitted to the
              Agency with the laboratory or  field study.  The Agency highly recommends that
              the ILV report follow the format in paragraph (f) of this guideline.

                     (A)  The independent laboratory should  submit performance data to the
                     registrant demonstrating that an adequate number of samples for  each test
                     level were extracted,  cleaned up,  and  analyzed.  Each set  should have an
                     appropriate number of spiked matrix control samples with  method control
                     and matrix control samples intermingled.

                     (B)  Results reported should include:

                           (1) Results of each performance sample set — LOD or the MDL,
                           the established LOQ, and accuracy and precision measured.

                           (2) The mean and individual  values for recoveries  and  standard
                           deviations  for the pesticide  parent, lexicologically  significant
                           metabolites and/or degradates in fortified matrix control samples at
                           each spiking level.

                           (3) The confidence intervals  (95 or 99%)  for  the  true average
                           recoveries at each spiking level.

                           (4) Individual values for recoveries at each spiking level.

                     (C) Any matrix or solvent effects that result in signal enhancement,
                     masking or suppression and the impact those effects have on the test
                     results is described.

(f) Reporting and reporting format. Information to be supplied in the report for each ECM for
a given matrix includes the information items listed in paragraphs (f)(l) through (f)(10) of this
guideline. Paragraphs (f)(l) through (f)(10) are also the recommended reporting format to aid
the applicant/registrant in generating reports which are compatible with the Agency's review
process.  Recommend for the ILV report that the IL also follow this reporting format, excluding
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information in paragraph (f)(7)(ix) and with modifications applicable to the IL, for submittal to
the registrant.

       (1) Title/cover page.

       (2) Certification.

              (i) For each ECM, the identification of those laboratories that  developed the data
              submitted to the Agency. For each ECM ILV, the identification of the laboratory
              that conducted the ILV and a statement that the  laboratory was requested to
              perform the ILV for the registrant.

              (ii) Certification of authenticity by the Study Director and Lead Chemist for the
              laboratory  that developed  the  method  (including  signature,  typed name,  title,
              affiliation, address, telephone number, and date).

              (iii) Statement of adherence  to the FIFRA GLP (40  CFR  part  160) or OECD
              Principles of Good Laboratory Practice, as appropriate.

              (iv) Statement of claims for non-confidentiality and that the method contains no
              trade secrets or proprietary data.

       (3) Table of contents.

       (4) Summary. Provide  a brief description of paragraphs (f)(6)(ii) and (f)(6)(iii) of this
       guideline.

       (5) Materials—

              (i) Equipment. A list and description of equipment used.

              (ii) Reagents and standards.

                     (A) List and describe the  source, purity and stability of analytical  grade
                     standards.

                     (B) Describe the source and preparation of reagents.

              (iii) Safety and Health.

                     (A) Provide material safety data sheets (MSDS).

                     (B) Describe any special precautions that need to be taken with standards,
                     solvents  or reagents and  any  procedural steps that  require special
                     precautions to avoid safety or health hazards.

       (6) Methods.

              (i) Principles of the analytical methods.


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(ii)  Analytical  procedures.    Describe  the  analytical  procedure(s)  for  an
environmental matrix in a detailed step wise fashion:

       (A) Sample matrix.  Identify the  source of the sample and characterize the
       sample  matrix.  For  example, characterization of a soil  sample might
       include  a description of its textural class and percent organic matter, and
       characterization  of a water sample might include pH, turbidity,  specific
       conductance, etc.

       (B) Preparation of samples.

       (C) Extraction.  Demonstrate efficiency in specific soil samples from field
       sites.

       (D) Fortifications.  Describe fortifications used during method validation
       runs.

       (E) Clean-up.

       (F) Derivization  (if any).

(iii) Instrumentation.

       (A) Description  of the instruction including make and model, type and
       specificity  of detector(s), column(s) (packing materials, size),  carrier
       gas(es), etc.

       (B) Operating   conditions of the  instruments including flow  rate(s),
       temperature(s), voltage, etc.

       (C) Calibration procedures (frequency and stability).

(iv)  Potential interference(s).  Describe the effects of the following on signal
enhancement,  masking  or  suppression  of signal and their impact on  the test
results:

       (A) Sample matrices.

       (B) The use of other pesticides on the test site.

       (C) Solvents.

       (D) Lab ware.

(v) Confirmatory techniques.  Describe confirmatory techniques (i.e., GC/MS,
LC/MS, second column, etc)

(vi)  Time required for analysis.   Give the time required to take  one sample set
completely through the analytical  procedure,  including  sample  preparation,

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       extraction, cleanup, derivatization, and determination steps. Identify those steps
       that could significantly increase the time required to complete the method.

       (vii) Modifications  or potential problems.  Specify any allowable variances and
       describe  any unique steps where  little  variation is allowed  in the method.
       Describe any potential problems and/or  modifications that were made to  the
       analytical procedures.

       (viii) Methods of calculation.  Describe calculations in a step wise fashion for a
       specific individually spiked  matrix control  sample  at the LOQ which would
       include the raw data of the analysis,  calibration factors, calibration curves with the
       raw  data of all  of the  standards  used to generate the  curve for the parent
       compound, metabolites, and degradates, etc. with the calculations used to generate
       the final concentration and recovery of the spiked matrix control sample.

       (ix)    Copies    of   chromatograms/spectra.        Representative    sample
       chromatograms/spectra should be submitted  for each analyte measured in each
       matrix at all spiking levels, including method and matrix blanks.  In addition,
       chromatograms/spectra  with the  highest levels  of background and  poorest
       resolution and  copies  of the chromatograms/spectra for the  standards  used to
       quantitate the analyte(s) in the representative matrix are submitted in the report to
       the Agency.  Also recommend  submitting  a set of representative  sequential
       chromatograms.  Analyte peaks of interest should be correctly  labeled to show
       appropriate retention times, peak areas, and heights on each chromatogram.

       (x) Other.  Describe any and all additional information  the registrant considers
       appropriate  and relevant to provide a complete  and thorough description of the
       soil and water method.

(7) Results/Discussion.

       (i) Method validation results (include tables of test levels and results of analysis).

       (ii) Accuracy (mean, range of recoveries, standard  deviations and confidence
       limits for specific concentration levels, such as the LOQ or IQxLOQ).

       (iii)) Precision.  Provide the RSD at  each specific concentration level.

       (iv) Limit of detection. Provide a clearly written explanation of how this value is
       calculated and cite the reference.

       (v) Limit of quantitation. Provide a clearly written explanation of how this value
       is calculated and cite the reference.

       (vi) Ruggedness testing (if performed).

       (vii) Discussion of selectivity and specificity of method.
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              (viii) Limitations.

              (ix) Interference/calibration.

              (x) Independent laboratory validation.

       (8)  Conclusion.   Discuss  applicability  of the  ECM  for measuring specific  test
       compound(s) in the  study matrix or  various  matrices,  ranges,  expected recoveries,
       interference(s), etc.

       (9) Tables/Figures.

       (10) References.

(g) References. The following reference should be consulted for additional background material
on this test guideline.

       (1)  Organization for Economic  Cooperation  and Development,  1998.    Series  on
       Principles  of Good  Laboratory  Practice  and Compliance Monitoring  No.  1  OECD
       Principles  of Good Laboratory Practice, ENV/MC/CHEMC(98)17, Revised in 1997.
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