NEIC
I
EPA-330/9-79-001
PESTICIDE PRODUCT LABORATORY PROCEDURES MANUAL
July 1980
National Enforcement Investigations Center. Denver
.S. Environmental Protection Agency
Office of Enforcement
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF ENFORCEMENT
EPA-330/9-79-001
PESTICIDE PRODUCT LABORATORY PROCEDURES MANUAL
July 1980
Dean F. Hill
This manual was prepared by Dean F. Hill of NEIC in cooperation
with the Pesticides and Toxic Substances Enforcement Division,
Office of Enforcement; and the Technical Services Division,
Office of Toxic Substances.
NATIONAL ENFORCEMENT INVESTIGATIONS CENTER
Denver, Colorado
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I
FOREWORD
This manual is the culmination of several years of work and many
years of experience. The procedures set forth address those areas
which playa large part in the overall quality assurance effort in
the pesticide formulation enforcement laboratory. Safety and health
will eventually be addressed also, although technically not directly
related to quality assurance. Specific methodology is also not cov-
ered, primarily because of the other resources available and due to
the wide range of chemicals and products involved. The NEIC Pesticide
Formulation Methods Index should serve as an additional useful resource
in the methods area.
The NEIC Pesticide Product Laboratory Procedures Manual is ob-
viously incomplete, Chapters IX, XI, and XII not being fully ready
yet. These sections and any revisions for other chapters will be
automatically sent to all holders of this manual.
Any suggestions for changes, additions, or deletions are very
welcome and should be forwarded to:
Dean F. Hill
Pesticide Product Program Coordinator
EPA. Office of Enforcement
National Enforcement Investigations Center
Bldg. 53. Box 25227. DFC
Denver, CO 80225
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VII
VIII
XII
CONTENTS
I
INTRODUCTION. .
. .. .. .. . . . . .
. .. . . .. .. .. ..
.. .. .. . .
II
III
QUALITY ASSURANCE
SAMPLE COLLECTION
.. .. .. .. ..
. . .. .. .. .. .. .
.. .. .. .. . ..
.. .. .. .. .. .. ..
.. . .. . .
.. .. .. .. .. .. .. .. .. .. .. . .
IV
CHAIN OF CUSTODY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . .
SAMPLE CUSTODIAN. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RECEIPT OF SAMPLES AT THE LABORATORY. . . . . . . . . . . . . . . . . . .
HISTORY OF OFFICIAL SAMPLE FORM. . . . . . . . . . . . . . . . . . . . . .
STORAGE BEFORE ANALYSIS. . . . . . . . . . . . . . . . . . . . . . . . . .
HANDLING OF THE SAMPLE DURING ANALYSIS. . . . . . . . . . . . . . . . . .
STORAGE AFTER ANALYSIS. . . . . . . . . . . . . . . . . . . . . .
SAMPLE SOLUTIONS AND STANDARDS. . . . . . . . . . . . . . . . . . . . . .
SAMPLE RECORDS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SAMPLE ANAL YS IS. . . . . . . . . . . . . . . . . . .
SCOPE OF ANALYSIS. . . . . . . . . . . . . . . . . . . . . . . . .
STATUS OF CHEMICAL METHODS. . . . . . . . . . . . . . . . . . . . . . . .
ASSAY OF SAMPLES. . . . . . . . . . . . . . . . . . . . . . . . .
OEFECTIVE SAMPLES. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECK ANALYSIS. . . . . . . . . . . . . . . . . . . . . .
FINAL REPORT. . . . . . . . . . . . . . . . . . . . . . . . . . .
ANALYSIS BY TECHNICIANS. . . . . . . . . . . . . . . . . . . . . . . . . .
V
VI
RECORD KEEPING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ANALYTICAL NOTES AND OBSERVATIONS. . . . . . . . . . . . .
1-1
II-I
111-1
IV-l
IV-l
IV-2
IV-2
IV-3
IV-6
IV-7
IV-9
IV-9
IV-I0
V-I
V-I
V-2
V-3
V-4
V-7
V-8
V-8
VI-l
VI-l
VI-2
REPORTING RESULTS. . . . . . . . . . . . . . . . . . . . . VII-l
GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . VII-l
LA8 WORK COPY. . . . . . . . . . . . . . . . . . . . . . . VII-l
TYPING OF THE MANIFOLD. . . . . . . . . . . . . . . . . . . . . . . . . . VII-2
COMPLETION OF REPORT OF ANALYSIS FORM. . . . . . . . . . . . . . . VII-2
SCREENING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VIII-1
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VIII-l
CHLORINATED HYDROCARBON SCREENING. . . . . . . . . . . . . . . . . . . . . VIII-1
ORGANOPHOSPHATE SCREENING. . . . . . . . . . . . . . . . . . . . . VIII-3
SCREENING FOR OTHER CLASSES OF PESTICIDES. . . . . . . . . . . . . VIII-5
IX
LABORATORY INSTRUMENTATION. . . . . . . . . . . . . . . . . . . . . . . . . .
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . .
ANALYTICAL BALANCE . . . . . . . . . . . . . . . . . . . . . . . .
TOP-LOADING 8ALANCE I . . . . . . . . . . . . . . . . . . . . . . .
TOP-LOADING BALANCE II (Optional) . . . . . . . . . . . . . . . . . . . . .
pH/MILLIVOLT METER. . . . . . . . . . . . . . . . . . . . . . . .
INFRARED SPECTROPHOTOMETER. . . . . . . . . . . . . . . . . . . . . . . .
UNTRA-VIOLET/VISIBLE SPECTROPHOTOMETER. . . . . . . . . . . . . .
GAS CHROMATOGRAPH. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HIGH-PERFORMANCE LIQUID CHROMATOGRAPH. . . . . . . . . . .
CHROMATOGRAPHIC DATA HANDLING. . . . . . . . . . . . . . . . . . .
REFERENCE STANDARDS. . . . . . . . . . . . . . . . . . . . . . . . .
INTRODUCTION. . . . . . . . . . . . . . . . . . . .
SOURCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REPLACEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
X
XI
REFERENCE SAMPLES. . .
.. . .. . .. ..
.. .. .. .. .. ..
.. .. .. .. .. . .. .. .. .. .. . . . ..
SAFETY AND HEALTH
.. . .. .. . ..
.. . .. .. .. ..
. . . . .. .. .. .. .. ..
APPENDICES
A HISTORY OF OFFICIAL PRODUCT
B OFFICIAL SEAL
C LABORATORY VERIFICATION GUIDELINES
D REPORT OF ANALYSIS
E CONTAMINANT SCREENING GUIDELINES
F INSTRUMENT AUDITS
IX-1
IX-l
IX-l
IX-2
IX-3
IX-3
IX-6
IX-I0
IX-13
IX-26
IX-34
X-l
X-l
X-l
X-5
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.
INTRODUCTION
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1-1
I.
INTRODUCTION
A State or EPA pest i ci de product 1 aboratory is primarily an en-
forcement unit responsible for analyzing pesticide formulations (and
related materials) under the authority of the Federal Insecticide,
Fungicide and Rodenticide Act (FIFRA), as amended, or a corresponding
State law. State personnel also perform inspection and analytical
services under delegated authority of FIFRA, as amended.
Pesticides are defined in FlFRA to include preparations intended
for use as insect i ci des, fungi ci des,
rOdenticides, herbicides,
nema-
tocides,
antimicrobial
repellents,
animal and
agents, amphibian/reptile/fish poisons and
invertebrate repe 11 ents, plant growth regu 1 a-
and plant dessicants. Pesticide formulations
tors, plant defo 1 i ants
are derived from almost 1,000 different registered active ingredients
in a wide variety of combinations. Pesticide formulations also exist
in many application forms such as emulsifiable concentrates, wettable
powders, dusts, pressurized containers, baits, encapsulations, suspen-
sions, and ready-to-use impregnated plastics.
In addition, there is
now a trend towards sampling and analysis of use-dilution (or tank-mix)
materials in connection with use investigations.
Potential violations deriving from laboratory analytical find-
i ngs i nc 1 ude defi c i enc i es , over- formu 1 at ions and cros s:"contami nat ions.
Related physical measurements such as net contents, flammability and
emulsifiability may also result in enforcement actions. A product
that is chemically deficient will result usually in partial or total
inefficacy. Also, a definite health hazard may also result from a
chemical deficiency, as in the case of germicides, sanitizers and
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1-2
disinfectants,
institutions.
particularly those used in hospitals and other public
Over-formulations and cross-contaminations, in addition
to contributing to an unnecessary environmental burden, may also:
(1) create a potential applicator hazard by exceeding the label safety
category, (2) give rise to illegal crop or other commodity residues,
(3) give rise to adverse toxicity effects for formulations applied
directly on animals and fowl, and (4) lead to phytotoxicity among
desirable plant species. Undue flammability, particularly with re-
spect to pressuri zed contai ners, can create an obvi ous safety hazard.
Poor emulsification and other mixing problems, usually related to the
inert ingredients in a pesticide formulation, can lead to efficacy
and application problems.
Analytical testing is performed to determine whether an offi-
cially sampled pesticide formulation is correctly labeled, i.e., to
determi ne if the actual contents are descri bed by the active i ngre-
dient statement. Therefore, the label claims will be the basis for
the 1 aboratory to i ni t i ate ana lys is. The exception woul d be when
suspected pesticides arrive at the laboratory with a missing, or ob-
viously wrong, active ingredient statement. In such cases, the labora-
tory supervisor will have to determine the analytical level of effort
based on the merits of the case.
Among the 1 ega 1 actions (state and federal) that can occur as a
result of laboratory findings are: (1) stop-sale, (2) recall, (3)
seizure, (4) civil action, (5) criminal action, and (6) cancellation
and/or suspension or registration.
Thus it is i mperat i ve that all 1 aboratory operating procedures
and methodology be val i d from both asci ent ifi c and 1 ega 1 poi nt of
view. All results and conclusions must not only be accurate, but
defensible in a court of law. A single procedural or analytical
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1-3
error uncovered duri n9 the deve 1 opment or concl us i on of any enforce-
ment action can severely erode the credi bi 1 i ty of
The entire 1 aboratory staff must make every effort
tablished quality assurance criteria.
any 1 aboratory.
to adhere to es-
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,
QUALITY ASSURANCE
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II-I
II.
QUALITY ASSURANCE
The primary purpose of qual ity assurance in any enforcement ana-
lytical program is to assure a maximum degree of accuracy and defensi-
bility of data. This means not only providing certainty that analyti-
cal results are reliable, but also that criteria for chain of custody,
record keeping, reporting and sampling are considered as integral parts
of the overall quality assurance effort.
Quality assurance from a pesticide product analytical standpoint
can best be maintained by adherence to certain procedural standards
and participation in the analysis of inter-laboratory reference samples.
Adherence to procedural standards is critical, particularly with respect
to potential chemically violative products, because it is the analytical
results for these samples that are likely to be contested. The guide-
lines and criteria as spelled out in this document, if followed rigor-
ously in day-to-day practice, should establish a high degree of scien-
tific and legal credibility for any laboratory.
Inherent in any meani ngful qual i ty assurance program is the con-
tinued need for upgrading of per.sonnel, methods, instrumentation and
even the qual i ty assurance program i tse 1 f. Methods development and
collaboration should be continuously supported and encouraged. Methods
are needed that are specific, efficient and broadly applicable to
di fferent formul at i on types and mi xtures. Upgradi ng of methods to
higher status for inclusion in published works such as: J.A.O.A.C or
the EPA Manual of Analysis for Pesticides and Devices, and eventually,
following collaborative testing, to the A.O.A.C. Methods of Analysis
itself, is of utmost importance si nce the burden of proof can be sub-
stantially lessened. Attained experience and training are, of course,
basic to any quality assurance effort.
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.
11-2
Finally, the Quality Assurance Program itself must be flexible
enough so that adjustments can be made for new needs and correction
of shortcomings.
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SAMPLE COLLECTION
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111-1
III.
SAMPLE COLLECTION
Pesticide product sample collection for EPA and State laboratories
is normally not performed by analytical personnel; official samples are
collected, documented,
inspectional staffs.
and transferred to the laboratory by trained
Most formulation samples will derive from Producer Establishment
Inspections (PEl's) or the market place (wholesale or retail). However,
samples can also be collected at ports-of-entry, points of application,
and points of shipment.
Gui dance for co 11 ect ion, documentation, and shi pment for products
collected under the authority of FIFRA, as amended, is presented in detail
in Chapter 12 of the EPA Pesticides Inspection Manual. The single-most
important piece of documentation for each sample is the Collection Report
(CR), as it contains or references all the specific background information.
The EPA CR's are numbered consecutively on a nationwide basis, thus pre-
cluding any chance of duplication.
Any observed sample problems relating to collection, such as container
leakage, inadequate quantity, inadequate labeling, improper shipping, and
so forth, should be brought to the attenti~n of the laboratory supervisor
who should notify the inspector or the supervisory inspector of the problem.
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CHAIN OF CUSTODY
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j
IV-l
IV.
CHAIN OF CUSTODY
INTRODUCTION
Any official pesticide product sample has the potential of being
used as evidence in a legal proceeding. It is important that strict
custody criteria be adopted and followed by all state and EPA labora-
tories acting in an enforcement capacity. This applies from the moment
a sample is collected until its final disposition. Even products that
appear to be "chemically satisfactory" may have labeling, efficacy or
other deficiencies that could lead to enforcement actions.
This document will address Chain of Custody only from the time of
receipt at the laboratory. If it appears to the laboratory staff that
custody has been broken or improperly maintained during the inspectional
phase, then such deficiencies should be brought to the attention of the
laboratory supervisor, who will decide what action to take regarding
analysis of the questionable sample(s). The supervisor should also no-
tify the appropriate inspectional staff of the problem.
Chain-of-Custody procedures are necessary to ensure that the product
collected has not been tampered with in the event of any subsequent legal
action. Although actual tampering is very unlikely under most circum-
stances, it is very important, from a legal standpoint, to preclude any
doubt whatsoever regarding sample integrity.
The legal requirement
documentation and physical
ments are set forth in the
for Chain of Custody consists of two aspects:
sample security. Criteria for these two ele-
following sections.
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III
IV-2
SAMPLE CUSTODIAN
If possible, one person (and an alternate) in the laboratory should
be designated as Sample Custodian. This person may be a professional or
non-professional depending on the the size and operations of each indivi-
dual laboratory. This designated individual must be fully aware of the
custody requirements and potential hazard of pesticide formulations.
The Sample Custodian is responsible for officially receiving samples
into the laboratory and for proper storage before and after analysis.
The Samp 1 e Custodi an may also perform other re 1 ated duties such as
sample delivery within the laboratory, preparation of documentation
folders, maintenance of logbooks, disposal, and so forth.
RECEIPT OF SAMPLES AT THE LABORATORY
Upon receipt of officially collected pesticide samples, either from
a freight agency, U.S. Mail, inspector or other source, the shipping or
outer containers should be inspected as to their overall condition. Any
leakage or other evidence of dam~ge should be brought to the attention
of the supervisor. The supervisor will report such conditions to the
appropriate inspectiona1 staff and make a decision regarding analysis or
sample disposition based on the degree of damage and importance of the
sample.
Any Freight Bills, Bills of Lading, or other documentation related
to the incom~ng shipment should be initialed and dated by the Sample
Custodian. Such shipping documentation may represent a large number of
samples, thus a sheet of paper can be attached to the Freight Bill list-
ing all sample numbers in that shipment. This information should then
be retained in a secured laboratory file for future reference.
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IV-3
HISTORY OF OFFICIAL SAMPLE FORM
For those pesticide formulations that are collected under the au-
thority of FIFRA. as amended. a single "History of Official Sample. EPA
Form 3540-17(12-73)" should be initiated for each sample. For those
samples collected under state authority. but for which legal action may
eventually be taken by EPA. the state should employ the EPA form or a
State counterpart conforming to EPA Regional requirements. This form
documents the passage of the sample from its receipt into the laboratory
until its final disposition. Whenever an official seal is broken. or
the sample transferred between analysts or storage locations. it is man-
datory that such action be documented on the History of Official Sample
or its equivalent.
Items 1 to 14 (1st column) on the History of Official Sample are
to be handwritten in neatly by the Sample Custodian upon receipt of an
official sample into the laboratory (see Appendix A for examples). The
specific items should be completed as follows:
Item 1.
Item 2.
Item 3.
Item 4.
Item 5.
Item 6.
Official Sample Identification Number. Not a special
laboratory identification number. which sHould be placed
in the margin of the form. if necessary.
Complete EPA Registration No.. including state and distri-
butor1s designation, if applicable. Insert a dash if no
EPA Registration Number. State Registration Numbers should
be clearly identified as such on state custody forms.
Name of Product. Include Company name if part of the
title. If title is unreasonably long. write out the first
five words followed by three dots. If several sizes of
the same product have been collected as separate sample
numbers. parenthesize the size after the title.
Laboratory location or designation.
Date received at the laboratory.
Name of person receiving sample into the laboratory
(Usually Sample Custodian or alternate).
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Item 7.
Item 8.
Item 9.
Item 10.
IV-4
Name or title of person making delivery, e.g., IIU.P.S.
Delivery Personll, IIMailpersonll, etc. If individual's
name is known, particularly if local staff, then write
in his or her name. Would be actual person making pick-up,
if received directly from freight or Post Office.
Name of commercial carrier, U.S. Postal Service or IIby handll
if brought directly to the laboratory by inspector or other
staff person.
If sample condition appears to be satisfactory, that is, no
apparent leaking, broken or disfigured containers, then
write "OK. II If sample exhibits leakage, damage, etc., then
indicate as such and elaborate, if necessary, in Item 26,
Remarks.
The condition of the official seal should be noted. If
filled out correctly and intact, write "OK.II If the seal
is broken, missing or incompletely filled out, indicate
as such, and elaborate, if necessary in Item 26.
Any noteworthy observations regarding sample or seal condition should
be brought to the attention of the supervisor who will determine the dis-
position of the sample.
Item 11.
Item 12.
Item 13.
Item 14.
Person's name who sealed sample.
Date sample was sealed. If other evidence indicates that
this date is wrong, append the designation II(SIC)II.
Should reflect the number of individually sealed plastic
outer bags and the number of subsamples within each bag,
e.g. 111 x 211, 112 X 411 or 112 x 2 + 1 xlII.
Should designate the shelf and/or cabinet where the sample
is stored prior to analysis. If given directly to the an-
alyst, write IIGiven to (name).11
The analyst who performs the initial analysis should fill
15 to 19 upon receipt of the sample from storage or the Sample
Items 20 to 24 are completed after analysis has been finished.
out Items
Custodian.
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IV-5
Items 15 - 24 are completed as follows:
Item 15.
Item 16.
Item 17.
Item 18.
Item 1 9.
Item 20.
Item 21.
Item 22.
Item 23.
Item 24.
Name of the person who assigns the sample to the analyst
(usually the supervisor), senior chemist, or the analyst.
Name of analyst.
Person who delivered sample from storage.
Date delivered to analyst.
Total number of subsample containers received.
the same as the total in Item 13.
Usually
Number of subsamp1es actually analyzed (including physical
analysis).
Date seal broken by analyst.
Date resealed by analyst.
Name of individual (usually the analyst) who reseals
the sample.
Storage shelf location.
Whenever the sample is reassigned to another analyst for check or
additional analysis within the laboratory, then the second person will
fill out Items 15 to 24 in the second column in similar fashion.
Like-
wise, the third column or even additional sheets are used if necessary,
to document every sample transfer within the laboratory. If more than
one History of Official Sample is needed for an official sample, only
the headings (Items 1 to 3) need to be completed with the word
"(continued)" appended to the Sample Number.
Whenever a sample or a portion of it is transferred to another lab-
oratory for chemical, physical or biological testing, then a note is
made in Item 26. Remarks, under the Release Date regarding: (1) To
whom the sample is being sent,
(2) Why the sample is being sent, i.e.
"Check Analysis", "Special Request", etc., (3) Date the sample is sent,
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.
IV-6
(4) Mode of transportation of sample, and (6) Initials of person who
prepared the sample for shipment.
The original, or a photocopy of the History of Official Sample,
should be forwarded to the receiving laboratory along with the remainder
of the sample documentation and analytical results. The receiving lab-
oratory will then fill out the second column, starting with Item 4, simi-
lar to the first column. This process continues for each laboratory
that handles the sample.
00 not leave any spaces blank up to the point where the last Item
is completed. Insert a dash or IINAII if necessary. to indicate that such
a space was not overlooked.
STORAGE BEFORE ANALYSIS
Unless given directly to the analyst. official samples are stored
in a locked sample cabinet or room, on the shelf noted in Item 14 of the
History of Official Sample. Keys to the general sample storage area
should be accountable and limited only to those persons directly concerned
with handling the sample. i.e., the Sample Custodian, Laboratory Supervisor
and certain analytical staff. If there are no unsealed samples in the
storage area. it may be left unlocked for convenience purposes during
working hours. If unsealed samples are being kept in the general stor-
age area for any reason. then the cabinet or closet must be kept locked
at all times except for adding or removing samples. If any keys are
lost or unaccounted for. then the lock must be changed and new keys issued.
If it is anticipated that rodenticides or molluscide baits will be
tested for efficacy upon completion of chemical analysis, then a separate
/
locked storage cabi net must be provi ded. Separate storage for these
materials will minimize the possibility of contamination by foreign chemi-
cal odors deriving from stored pesticides. Contamination of this nature
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IV-7
can affect the acceptability of the bait material by rodents or molluscs
during subsequent efficacy testing.
HANDLING OF THE SAMPLE DURING ANALYSIS
When the analyst receives an official sample, Items 15 to 19 and 21
on the History of Official Sample are completed as described previously,
and any internal laboratory logbooks or records are completed as neces-
sary. The inspector's seal is broken by tearing, and then initialed and
dated (see Appendix B). If possible, the plastic bag enclosing the sample
should be opened in such a way as to preserve reuse of the bag after
analysis is completed. If it is necessary to cut or tear the bag open,
then it should be retained and stored with the remainder of the sample.
Any observed discrepancies regarding the seal, sample identification or
sample condition, not previously noted by the Sample Custodian, should
be described, initialed and dated in the Remarks Section of the History
of Official Sample and brought to the attention of the supervisor.
The broken and initialed seal should be removed, if possible, from
the plastic bag and taped to the sample container, avoiding the conceal-
ment of any label wordi"ng. If the broken seal cannot be conveniently
removed without tearing to pieces, the broken seal can be left attached
to the neck of the plastic bag. In any event, all broken seals are to
be retained with the original sampl~.
During the time that the sample is unsealed and undergoing analy-
sis, it is very important that the sample be kept in a locked cabinet or
room for which only a restricted number of personnel have access. When
unsealed, the sample should be kept locked up at all times, except when
actually being handled.
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1M
IV-8
When the original analysis is complete, the analyst officially re-
seals the samples in an inverted* polyethylene bag using a new seal. The
EPA seal should be completed as shown in Appendix B. Any State seal
should be completed according to local custom, but should contain at a
minimum the analyst's name, title and date.
The use of polyethylene bags is preferable to direct sealing of
bottles, jars and other containers. Their use should also be encouraged
by inspectional staff. A sample enclosed in an officially sealed
inverted polyethylene bag presents a defensible item of evidence; the
sample cannot be reached without breaking either the seal or the bag.
With the bag inverted, the heat seal normally at the bottom of the bag,
will be enclosed as an additional measure of security. The use of clear
plastic bags assures that the label and container markings can be ob-
served without breaking open the bag each time.
Another advantage of polyethylene bags is that if a bottle or jar
is leaking, or is accidentally broken, the bag will usually contain the
bulk of pesticide until it can be safely disposed of. Undesirable odors
often associated with pesticide samples are also minimized. Clear poly-
ethylene bags are available in a wide variety of widths, lengths and
thicknesses, but 611, 911 and 1211 x 3611 have been found to be the most
useful. A 4 mil thickness. is adeq~te to provide protection without being
difficult to knot. Large clear trash bags are also desirable to have
on hand if retail-size fertilizer/pesticide combinations are expected to
be received for analysis.
The top of the bag can be knotted, folded and/or taped in a wide
variety of ways, the critical factor being that the sample should not be
attainable except by tearing or cutting the seal or bag. If it is neces-
sary to use several bags for multiple samples, then the seals should be
identical for each. Large fertilizer bags. may be officially sealed, if
~'r
Turned inside-out.
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.
IV-9
large clean plastic bags are not available, by placing four identical
seals over each of the four corners of the bag so as to cover the ends
of all draw strings.
Whenever a check or additional analysis is completed, or the plas-
tic bag has been opened for any reason, the sample is then rebagged,
resealed, stored and recorded just as performed for the original analy-
sis.
STORAGE AFTER ANALYSIS
The sealed samples, after completion of analysis, are placed in a
secured, well-ventilated sample storage area as designated in Item 24 on
the History of Official Sample. All bags, container parts, sprayers,
trays, caps or other remains of the original sample are to be retained
and sealed. The general storage location for completed samples may be
the same as that for incoming samples, as long as the two areas are seg-
regated. Bait samples should be stored separately from other pesticides
if efficacy testing is anticipated.
All official samples should be retained until notified by the appro-
priate legal or inspectional personnel that the case is no longer active,
i.e., placed in Permanent Abeyance (PAid).
SAMPLE SOLUTIONS AND STANDARDS
For the same reason that unsealed samples must be maintained under
strictest security while in the analyst's custody, prepared sample and
associated standard solutions should also be secured when not in actual
use. From a legal point of view, these solutions are just as susceptible
to tampering as the sample itself. This requirement is critical during
the analysis of potentially violative formulations, as the laboratory
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.
IV-IO
will likely be legally accountable for the analyses of these samples.
Any solutions prepared for future analysis must be stored in the analyst's
locked cabinet or other secure area. Such containers should be clearly
identified as to contents and date prepared.
If it is necessary to leave a digestion or other mixture in a hood
or unlocked refrigerator overnight, a completed official seal should be
placed across the closed hood sash or door, then broken, initialed and
dated upon reopening. This seal should be identified as "laboratory
use II in the margin and retained with the other sample seals. The infor-
mation regarding the sample and standard solution integrity should be
recorded on the worksheet.
Analytical and technical pesticide standards, both bulk and working
solutions should be kept secured along with any primary reagent standards.
Reagents,
storage in
solvents, reagent solutions, titrant, etc. may be kept in general
the laboratory (assuming adequate safety precautions are taken)
appropriate reagent blanks and titrant restandardizations are
during the confirmation of any potentially violative sample
as long as
performed
results.
SAMPLE RECORDS
All records relating to any active official pesticide sample are to
be handled essentially as confidential information: before, during and
following analysis. Sample documentation and active laboratory records
should be secured in a locked desk drawer or file cabinet when not in
use. Sample records, including worksheets, graphs, notebooks, chromato-
grams, notes and other material should also be locked up when not in
use.
It is up to laboratory custom as to the extent of record copies
that need to be retained for any active official sample after the
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;
.
;'
IV-II
analytical report is finished. It is critical, however, that all original
laboratory data including worksheets, notes, chromatograms, graphs, and
the related material be retained, along with the handwritten master copy
of the Report of Analysis (or the State equivalent). It has been found
useful to also keep a copy of the typed Report of Analysis, History of
Official Sample and Collection Report for all samples, and in addition,
a copy of the label and pertinent supplementary documentation for poten-
tially violative samples.
When notified of final disposition, or a Permanent Abeyance notice
is received by the laboratory, the physical sample may be disposed of,
and the records placed in a general file for future technical reference.
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1&
SAMPLE ANALYSIS
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./
V-I
v.
SAMPLE ANALYSIS
SCOPE OF ANALYSIS
The bas i c task of the 1 aboratory is to
label claim (or Registration disclosure) for
tion accurately describes the material actually
determi ne whether the
any submitted formula-
in the container.
It is not necessary, and may even be impossible with current
methodology, to analyze for all active ingredients in every pesticide
formulation. Active ingredients that appear to be present more for
their solvent or diluent properties than for their pesticidal activity
normally need not be determined, e.g.. petroleum distillates, alcohols,
mineral oil, silica gel, and diatomaceous earth. Soaps, detergents,
essential oils, creosote, complexing agents and polybutanes are examples
of other active ingredients not ordinarily analyzed.
A qualitative test for the active ingredient(s) may be all that
can be accomp 1 i shed for some products such as low-percentage active
ingredient bait materials and complex disinfectants. With such formu-
lations, it is often difficult to substantiate beyond a reasonable
doubt any deficiency or overformulation because of the methodology
1 imitat ions. An efficacy test is usually more meani ngful for these
types of formulations.
Certain types of pesticide products are more effectively analyzed
for their inert ingredients, e.g., pine oil-soap mixtures, creosotes
and coal tar derivatives. Water and alcohol are the usual inert ingre-
dients in such products, and can be determined easily by distillation.
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V-2
Adherents and asphalt sprays are examples of products for whi ch
no chemical analyses are performed.
STATUS OF CHEMICAL METHODS
A 1 though there is no offi ci a 1 ranki ng of methods in
analysis of pesticide products, the current edition (and
of the Official Methods of the Association of Official
--
EPA for the
supplements)
Analytical
Chemists (AOAC)
is genera lly accepted as contai ni ng the most val i d
methods from asci ent ifi c and enforcement vi ewpoi nt. The procedures
have been tested coll aborat ively between 1 aboratories, and thei r sta-
tistical reliability has been confirmed. These methods are termed
"Official" and should be employed, whenever possible, when confirming
potentially violative samples. It should also be kept in mind, however,
that a particular AOAC method may not be applicable to all types and
combinations of formulations for a particular pesticide, and that
complete extraction should also be verified, if necessary.
The next most authoritative source of pesticide formulation methods
are those in the EPA "Chemist's Manual II , i.e., the Manual of Chemical
Methods for Pesticides and Devices.
The methods given in this manual
and not 1 isted as "Tentative" may be considered "Standard. II
Standard
methods have proven reliable through wide use by regulatory analysts
over the years, but have not necessarily been subjected to interlabora-
tory collaborative testing. Other methods that may also be considered
as Standard for pesticide formulation analysis are those adopted by
other authoritative testing groups such as ASTM, AWPA, CIPAC (except
joint AOAC - CIPAC methods) and NBS. Applicable methods given in
Scott IS. Rosi n, U. S. Pharmacopei a, National Formul ary and recogni zed
scientific journals (such as J.A.O.A.C.), may also be considered as
Standard.
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...
V-3
All
other available methods
shoul d be
considered Tentative.
These
include
experimental,
industrial
and hoc methods,
Tentative
methods in the EPA Chemist's Manual, and methods in Zweig.
ASSAY OF SAMPLES
Initial Analysis of Routine Samples
Samples are selected by the supervisor or analyst with regard to
expediting special or priority cases, maximizing efficiency and mini-
mi zi ng the average turn-around-time. The average process time for
routine samples should be less than 30 days, whereas priority samples
should be analyzed as soon as possible. Several laboratory practices
which support these requirements are: (1) scheduling the analyst to
begin samples requiring long digestions and extractions and during
these operati ons completing sampl es whi ch requi re close attention.
(2) assigning to one analyst all samples containing the same ingredient,
and (3) screening as many samples as possible for cross-contamination
at one time.
The initial determination of an ingredient or combination of
ingredients for a routine sample should be made by the most expedi-
tious specific method available that can be expected to yield a re-
liable result. Thus, generally a non-AOAC procedure will be under-
taken for most organic pesticides, i.e., gas or liquid chromatography
using normal laboratory columns and conditions. Chromatography is
rapid and specific, but there are few collaborated methods employing
these techniques.
If more than one batch or code number is i ndi cated as bei ng rep-
resented for a single official sample, either from the container or
the Collection Report, or there are other apparent label or physical
differences between containers, then representative portions from
each should be analyzed.
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V-4
When the sample results for the initial analysis are satisfac-
tory wi th respect to the Laboratory Verifi cat ion Gui de 1 i nes (see
Appendix C) the final report is written up according to established
procedures. It is a good practice, however, to verify with a dupli-
cate analysis, results that are border1ine, i.e., fall within 20% of
the percentage limits of the Laboratory Verification Guidelines.
DEFECTIVE SAMPLES
Initial Results
If the results obtained upon first analysis indicate a potentially
violative sample according to the Laboratory Verification Guidelines
criteria, confirmatory procedures must be initiated. Each of the
additional analyses performed by the original analyst to verify his
or her original result (which indicated a defective sample) are termed
"confirmatory analyses," in order to differentiate such work from
"check analyses," which represents work accomplished by a second analyst.
If the initial method employed by an analyst for a defective
sample is not Official or Standard, the analyst should confirm the
original result by reanalyzing according to a more established method,
if available. This analysis should be performed in true duplicate.
A true duplicate analysis represents two separate determinations by
exactly the same method, but utilizing two separate sample charges
and standard solutions (if applicable). In addition, if more than
one uni tis avail ab 1 e for the sample, then at 1 east one other con-
tainer (preferably from a different case) should be analyzed. Separate
batch or lot numbers should be handled as completely independent samples.
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V-5
When a titration is performed as the confirmatory or check analysis
of a potentially violative sample, a restandardization of the titrant
should also be performed in conjunction with the analysis. If a diges-
tion,
preci pitat i on or other chemi ca 1 reaction is carri ed out as part
of a wet chemical technique, then a reagent blank must be performed
and recorded.
If an AOAC or Standard Method is used initially for the assay of
a defective sample, and there were no indications of interference or
other analytical problems, then the initial result should be confirmed
by repeating the ana lys is us i ng a new sample charge and, if app 1 i cab 1 e,
a new standard solution. The considerations previously mentioned
regarding batch codes, multiple units, restandardization and reagent
blanks still apply. When incomplete extraction is suspected to be a
cause of low results for a sample using an Official or Standard pro-
cedure, the results should be verified by either lengthening the extrac-
tion time, significantly modifying the sample/solvent ratio or employing
successive extractions. Soxhlet extraction or use of more polar solvents
may also be used for verifi cat i on of complete extraction, but extreme
care must be taken to avoid thermal decomposition or co-extraction of
normally insoluble inerts.
Overformulations using any technique, particularly chromatographic
or spectrophotometri c methods, should always be verifi ed for absence
of potent i a 1 interferences by use of alternate methodo logy, or at a
minimum using two significantly different GLC columns or HPLC conditions.
Apparent overformulate~ quarternary ammonium chlorides, as analyzed
by the AOAC chloride titration should also be confirmed using the
Epton, ferricyanide or other specific method, due to the possible
presence of free chloride.
Results for potentially violative samples using a Standard method
(no applicable AOAC procedure) should be verified by an alternate
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!
V-6
Standard method,
if available and applicable.
The alternate method
should be distinctly different from the first, such as IR and GLC, UV
and gravimetric, or HPLC and GLC, and not simply a variation in detec-
tor, column or solvent.
If only Tentative (including in-house or ad-hoc) methodology is
available for a particular formulation, at least two, or if possible,
three entire ly different procedures are necessary for confi rmat ion.
Consideration must also be given to extraction, calibration, specifi-
city and spiked sample recovery for all such cases, in addition to
the need for dup 1 i cate ana lys is by at 1 east one of the methods. Also
at least two units should be analyzed, if available. It may be neces-
sary to employ an elemental analysis to confirm violative samples in
such cases, although normally such methods are discouraged due to
lack of specificity. Supervisory discretion should be utilized when
determining whether to declare a sample as volative using a single
non-Official or non-Standard method.
Supervisory discretion and scientific judgement will also have
to be exercised when results do not agree between units or. when results
between different methods fail to agree.
For all suspect violative samples where multiple active ingredients
are present, and the methodology employed is not specifically applicable
to such mi xtures, then potential interferences shoul d be pos i t i ve ly
ruled out or shown to have a negligible effect on results. This can
be done by means of spiked samples, independent blanks using the co-
ingredient(s) or by reference to previously developed information.
In any case where a single result appears to be anomalous, and
probably due to some 1 aboratory error, then the resul t shoul d not be
reported. However, a note should be added to the worksheet data stating
"Not Reported, II along wi th a bri ef reason if one is known or suspected.
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V-7
The analytical report is completed and submitted to the super-
visor when all analyses (including screening for cross-contaminants)
are completed for a potentially violative sample, and the results are
cons i dered to be in good agreement. If the 1 aboratory is us i ng the
EPA Report of Analysis form, the upper part of Item 11, Results of
Analysis, should be left blank to be completed by the supervisor after
the check analysis is performed.
The supervisor should review the initial results and Chain of
Custody to this point and assign the sample to a second chemist for
check analysis. If the laboratory has only one chemist experienced
in pesticide product analysis, it may be necessary to have the check
analysis performed in another laboratory. In any event, whether the
sample is assigned to a second chemist within or outside the laboratory,
strict custody is to be maintained.
CHECK ANALYSIS
All potentially violative samples, as determined by the original
analyst's results and the Laboratory Verification Guidelines, are to
be further verified by a "check analysis" performed by a second exper-
ienced chemist. The check analysis precludes any possible error or
personal bias in laboratory procedures, methods, observations, or
calculations.
Prior to starting actual analysis, the check analyst should check
all the calculations of the original analyst and make a note of this
by writing "checked" along with initials and date by each result on
the worksheet. Oi scovered errors shoul d be corrected by the or; gi na 1
analyst along with initials and date.
The check analysis is usually just a single result obtained on a
single container of the suspect product. The method employed mayor
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loa
v-a
may not be the same as that used by the original analyst; however, if
an Official or Standard method is available, but not employed by the
first analyst for some reason, then it definitely should be used,
preferably in true duplicate. Titrants, standard solutions and other
prepared reagents used by the initial analyst are not to be used by
the check analyst. Independent restandardizations and reagent blanks
are also performed, if applicable.
In all cases where different containers yield substantially dif-
ferent (but verifiable) results, a check analysis should be performed
on each.
In the event of a discrepancy between the second analyst and
original analyst, the check analyst should first repeat his or her
work to rule out possible laboratory error. If at this point the
discrepancy still stands, the supervisor will have to use his or her
discretion to resolve the difference.
FINAL REPORT
When the check analysis is completed and the results are in agree-
ment with those' of the original analyst, the sample is resealed and
stored. The supervisor will then verify the check analyst's calcu-
lations, review the work in general to make sure the methodology was
appropriate, and summarize the findings. On EPA Reports of Analysis,
Items (top portion) 12 and 11 are completed as described in Section
VII. The report is then ready for typing.
ANALYSIS BY TECHNICIANS
when:
Initial results developed by non-professionals are defensible
(1) the individual has had at least 1 year's experience in the
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.
V-g
particular type of analysis being cons.idered, (2) the individual works
under the technical supervision of a chemist, and (3) all of the Chain
of Custody and confirmation criteria as previously spelled out have
been met.
I f these conditions are not met, the techni ci an, upon di scovery
of a potentially violative sample, should officially turn the sample
over to a chemist or more experienced technician for completing the
initial analysis.
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.
RECORD KEEPING
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'"
VI-l
VI.
RECORD KEEPING
INTRODUCTION
It is imperative that detailed and specific notes be made re-
garding all sample analyses, manipulations and observations. This
requirement is significant because many litigated cases do not reach
the hearing or trial stage until long after the analysis has been
performed, in some cases up to several years. Sufficient detail should
be provided to enable not only oneself, but others to reconstruct any
analysis step-by-step. Detailed notes not only serve litigation pur-
poses, but will also assist in resolving disputed analyses, and provide
specific methodology for future similar types of samples.
It is recommended that all analytical work, graphs, charts, notes,
etc., be retained in a general laboratory locked file cabinet by sample
number. This is not to say that each analyst should not keep a notebook
or logbook, but the file system will assure that all primary information
regarding a particular sample is in one location, Le., it is not
spread through a single analyst's. notebook or through several analysts'
notebooks. There is also less chance of loss.
If EPA Report of Ana 1 ys is, 3540- 5 (Rev. 5-76) is used, deta il ed
i nformat ion concerni ng ana lyses and observations shoul d be kept on
the back of the
used as long as
The face needs to
Lab Work Copy. As many sheets as necessary can be
they are identified by sample number and analyst.
be completed for only one sheet, however. Differ-
ent sheets
numbered.
should follow in chronological order and be sequentially
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VI-2
If laboratory notebooks are used, they should be of the "two-page"
carbon or pressure-sensitive paper type. The originals are then re-
moved from the notebook for retention with the laboratory records.
ANALYTICAL NOTES AND OBSERVATIONS
other
Careful notes should be made of the physical state, color, and
pertinent observations regarding the sample, particularly if
there
is phase
separation,
emulsification,
non-uniformity,
or other
irregularities.
The preparation of the product for analysis should be accurately
documented as to how and when (date) the material was mixed, subsampled,
and treated. If the sample was ground, sieved, homogenized, filtered,
or otherwise manipulated, give an accurate description of the amount
of subsamp 1 e, the techni que used, and the duration of the act i vi ty.
Also note any related observations, such as color, odor, or temperature
change. All net contents measurements shoul d be recorded in detai 1.
If it is necessary to determine non-volatiles for a pressurized con-
tainer, note the temperature and time of heating or standing, and
whether any spraying or spillage of non-propellants occurred.
Each method of analysis used should be referenced, and specific
notes made of any variations. Note should be made of all manipula-
t ions, reagents, and observations when the method used is not refer-
enced. Each laboratory operation should be accurately documented as
to date performed, particularly when an analysis or several analyses
of a sample extend beyond one day. Time of starting and stopping
shoul d be recorded for all ope rat ions where duration is a factor,
such as extractions,
and derivations.
separations,
centrifugations,
co lor formations,
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VI-3
Photographs should be taken, if possible, of any obvious physical
abnormality, such as poor applicator or container design, extreme
non-uniformity, layering and so forth, particularly if the condition
could result in adverse safety, health, or environmental effects.
Photographs or good photo copi es
thin-layer chromatographic plates
All photocopi es shoul d be mounted
should also be made of developed
incases of cross-contami nat ion.
on heavy paper and identified as to
sample number, date, analyst, and subject matter.
Custody information and storage location should be documented if
sample and/or standard solutions are stored overnight.
Reference standard information, including source, purity, and
age should be recorded along with appropriate weighing and dilution
data. If a reference standard is used that was prepared at an earl i er
date, then the original weighing and dilution data should be referenced.
All
instrumental
conditions should be recorded either on the
worksheet or on an appropri ate chart, graph or pri ntout. All graphs,
charts, and pri ntouts shoul d be i dent i fi ed by sample number, date,
analyst and determination number.
Gas chromatography data should be recorded for each analysis at
least to the following extent:
1. Gas Chromatograph
- Make, model and detector.
Include designation if more
than one of same model is
avail ab 1 e
2.
Column
- Source and/or date prepared
- Length, I.D., O.D. and compo-
sition
- Packing (%, type and source)
3. Conditions
- Temperature of oven, injection
port, detector, transfer lines,
etc.
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..
;'
4. Injection
5. Response
6. Internal Standard (if used)
7. Any conditioning or calibration
8. Recorder
..
VI-4
Flow rates, composition and puri-
ty of carrier, detector and
purge gases
- Electrometer conditions such as
range, attenuation, voltage, amper-
age, etc.
Amount injected and size of syringe
Digital integration (incl. make,
model, slope sensitivity and other
pertinent parameters) planimeter,
peak height, cut and weigh, etc.
Identification, source and con-
centration
Make, model, range and speed
HPLC data to be retained for each analysis should include at least
the following:
1. Liquid chromatograph
2. Detector
3. Column
4. Mobile phase
5. Injector
6. Temperature
7. Sample handling
Make, model, type and lab
designation
Make, model, type and wave-
length
Source and/or date prepared
Length, 1.0., 0.0. and compo-
sition
Packing (type, source and par-
ticle size)
Pre-column, if applicable
Isocratic or gradient?
Name and % of each solvent
Degassed? Filtered?
Type, make and model
Amount injected
Type of control and temperature
Filtration? Pore-size of filter
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*
VI-5
8. Response measurement
- Digital integration (incl. make,
model and settings) planimeter,
peak height, etc.
9. Recorder
- Make, model, range and speed
10. Internal standard
- Identification, source and
concentration
Spectrophotometric data should be retained to the extent called for
on the specific charts, along with any additional information as may be
relevant to the measurement.
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I
REPORTING RESULTS
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VII-l
VII.
REPORTING RESULTS
INTRODUCTION
Analytical results generated under the authority of FIFRA, as
amended, should be reported using EPA Form 3540-5 (Rev. 5-76) or State
I
equivalent as agreed to under the grant requirements.
The EPA Report of Analysis consists of a six page manifold, broken
down as follows:
l.
2.
Sample Record Copy
Establishment Copy
Regional Office Copy
Laboratory Copy
Biological Lab Copy
Lab Work Copy
3.
4.
5.
6.
LAB WORK COPY
The Lab Work Copy is composed of heavy card stock and shoul d be
removed from the manifold prior to analysis. A group of cards can be
removed and given to each analyst and the cardless manifolds forwarded
to the typist.
The reverse side of the Lab Work Copy can be used for recording
of all laboratory data as spelled out in Section VI. Upon completion
of analysis, the front side of the Lab Work Copy should be filled out
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VII-2
by the analyst for use as the typist's master. When the typing is
normally performed outside of the laboratory, a photocopy should be
submitted for typing to minimize the chance of losing the original.
TYPING OF THE MANIFOLD
Typing should be performed on those manifolds from which the Lab
Work Copy has been removed. The Estab 1 i shment Copy is fo 1 ded in half
by inserting the bottom half under the top half so that only about 1
3/4" is exposed under Item 11. This will allow for further elaboration
of results and comments on the in-house copies without carrying over
this information, either in print or impression, to the Establishment
Copy. Another a 1 ternat i ve is for the typi st to tear out the Estab-
lishment Copy after completion of the first part of Item 11.
Thus Item 11 of the Report of Analysis is subdivided into two
sections, the bottom half of which is meant for in-house (State or
EPA) use.
If it is necessary to prepare typewritten drafts, then blank
manifolds may be torn apart and the pages used individually, except
for the Establishment Copy.
COMPLETION OF REPORT OF ANALYSIS FORM
The analyst should complete the front of the Lab Work Copy except
for Items 12, 13, 14 and 15 (see examples in Appendix D). The Supervisor's
Summary in Item 11 for those samples that are potentially violative
or otherwise noteworthy should also be left blank. Any items that
are in doubt or unknown should be left blank and brought to the attention
of the supervisor.
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VIl-3
As much information as possible should be obtained from the
actual product label rather than relying on information in the Collec-
tion Report, since the latter may contain typographical errors.
1.
Sample No. - The official sample number.
2.
Date Collected - Date on official seal.
3.
Region - EPA Region in which the sample was collected.
4.
EPA Reg. No. - The EPA Registration Number on the label
itself, and should include the entire number including
state designation (usually several letters), if any, and
distributor designation. For example, the number could
be 356-7," 11356-7-AAII or 11356-7-AA-6798l." If no EPA
Reg. No. insert a dash.
5.
Establishment No. - The producing plant Establishment
Number given on the label or container. This designa-
tion is a number followed by the state initials, followed
by another number, e.g. 356-CA-l. The Establishment No.
may not be directly discernable, i.e. it may be stamped
on the bottom of the container or otherwise given as a
perforated (or hand-marked) code. If there is no EPA
Est. No. on the label or elsewhere on the container, in-
sert a dash.
6.
Description of Sample - Consists of two parts separated
by a semicolon or slash mark. The first part should be a
physical description of the exterior sample and the second
should describe the physical appearance of the actual pesti-
cide material. Examples are given as follows:
2 x 1 lb. cardboard canisters/tan dust
4 x 12 fl. oz. pressurized containers/yellow liquid
1 x 1 gal. plastic jug/blue liquid
2 x 1 pt. subsamples in glass bottles/amber liquid
1 x 4 lb. cardboard carton/brown pellets
7.
Name and Address - Name, title and address given on the
Receipt for Sample, if available. If the information is
not clearly identifiable from the Receipt for Sample,
Collection Report or other documentation, it should be left
blank to be completed by the inspectional office.
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...
VII-4
8.
Product Name - Should be relatively short, yet yield enough infor-
mation to clearly identify the product. The Company name should
be included if it is an obvious part of the title. If more than
one report is being prepared to reflect different size containers
of the same product, the respective sizes should be appended to
the product name in parentheses.
9.
Lot or Code Number(s) - As given on the actual product, if present,
otherwise as noted on the Collection Report for codes from shipping
containers. Insert a dash if no code or batch numbers.
10.
Name and Address of Producer - Actual producer or formulator of
the product if not the same firm given for Item 7. This will
require completion for non-PEl samples, such as those deriving
from market surveillance, use/misuse, import, experimental-use
and accident investigations. This information should include
firm name, city, state and zip code if possible. If this item
is the same as Item 7, then insert a dash or the words "Same as
above."
11.
Results of Analysis
a.
Upper Portion
(1)
For Chemically Satisfactory Samples
Within the upper 1 3/4" of this Item, the statement
"This sample has been analyzed and been found to be
chemically satisfactory" can be made (see Appendix D).
For those samples which have been analyzed and been
found not to be particularly satisfactory, but for
which no action should be taken due to sampling diffi-
culties, poor methodology, borderline results or for
some other reason, simply designate as "Passed."
As an alternative, give a short summary of the results
found as described below for chemically unsatisfactory
samp 1 es.
(2)
For Chemically Unsatisfactory Samples
Provide a brief summary of results, including method,
ingredient and amount found. Quote the method reference
only if AOAC, EPA or other recognized method source.
In recording the amount found for deficiencies give
only the highest average for all the work performed.
If two or more methods were used and the results were
comparable, then the highest result (or highest average)
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j
b.
V!I-5
should be reported for each method. For overformu1ations
and cross-contaminations. report the lowest result or
average for each method.
Lower Portion
(1)
General
On the lower portion of Section 11. the laboratory
work is summarized in more detail. whether the sample
is analytically satisfactory or not. Information is
included concerning net contents. screening and any
other pertinent information along with a more detailed
summary of the analytical results than that given in
the upper portion (see examples in Appendix D).
The lower section should be headed by the analyst's
name and the date reported.
(2)
Chemical Names
The chemical names employed in the report should be as
listed on the label unless: (1) there is an obvious
misspelling. (2) an ingredient is discovered that is
not listed. or (3) the label makes no claim as to active
ingredient(s). In all of the aforementioned cases.
quote the prime referenced name listed in Acceptable
Common Names and Chemical Names for the Ingredient
Statement on Pesticide Labels, 3rd Edition (EPA-540/4-
75-011, Dec. 1975). The common or official name of
any pesticide is preferable if listed on the label.
(3)
Methods Reporting
When reporting analytical methods. give a brief de-
scriptive title of the technique and a reference source
or number. e.g.:
Malathion (Colorimetric; AOAC 6.336)
Total phosphorus (Gravimetric; EPA-1)
Ch1orpyrifos [GLC; J.A.O.A.C. 56. 1094 (1973)
Pyro1an (GLC; Zweig VI. p. 471)
Sodium Hydroxide (Titration; Rosin-5. p. 404)
If modifications were made to the referenced methods,
append the abbreviation IImodll after the reference, and
describe the modification as a brief note only for
those samples that are potentially violative. Always
fully describe any method modifications in the laboratory
notes.
-------
VII-6
When a method used has no immediate reference, or has
been adapted for a particular sample, describe the
method in brief, but sufficient, detail so that
another chemist reviewing the report can understand
the essential steps of the method.
For GLC analysis, describe the column,
ture and internal standard (if used).
zation should also be noted. Examples
follows:
oven tempera-
Any deriviti-
are given as
Malathion (GLC; 3% OV-l @ 180°)
p-Dichlorobenzene (GLC; 3% XE-60 @ 100°, I.S.-DDVP)
2,4-Dichlorophenoxyacetic acid (GLC; 3% OV-17 @ 170°
as methyl ester)
HPLC analyses, not referenced elsewhere, should be de-
scribed by the column, eluant and detector wave-length,
e. g.:
o-Benzyl-p-chlorophenol (HPLC; ~ Bondapak C18 CH30H/
0.0025M H3P04- 65/35 @ 238nm)
Thiram (HPLC; ~ Bondapak C18. CH3CN/H20-55/45 @ 280 nm)
For spectrophotometric methods not given elsewhere, the
wavelength and solvent should be reported, e.g.:
Phenothiazine (IR; 1300 cm-1 in CS2)
2-(Naphthyloxy)acetic acid (UV; 272 nm in H20)
Dimethoate (NIR; 2930 nm in CHC13)
Derived methodology for potentially violative samples,
should be further described in a note, giving such infor-
mation as extraction conditions, clean-up, cell thickness,
type of detector etc.'
(4)
Analytical Data
When a quantitative analysis is performed, the actual
percentage of ingredient found should be reported. If
more than one analysis by a single method on a single
container is performed, and the results are comparable,
the average should be reported in addition to the
individual results. Results by different methods or on
different containers should not be averaged.
-------
""
VII-7
When different containers are analyzed the results
should be identified as sub 1, sub 2, etc. If the
inspector has not marked the submitted samples as such,
the analyst should mark each sub sample appropriately
along with his initials and date.
When a semi-quantitative analysis is performed (e.g.
TLC) give the interpreted result preceded by the desig-
nation "Est". TLC results are considered to normally
reflect a precision of %20%.
For qualitative tests, simply specify "Present" or
"None Detected" as appropriate. When no ingredient is
detected, the detection limit should be determined and
given in a note.
Net contents, if estimated, should be reported as "satis-
factory" or reported as given on the label. If a defi-
ciency in net contents is detected, then the average of
all containers should be reported under the "Found"
column, and the individual weights listed below. The
tare weight(s) should also be listed and identified.
Cross-contamination screening results for which no
contaminants are discovered can be reported as:
"Screening (TLC; CL & P):
Satisfactory"
If contaminants are detected and confirmed, write "(name
of contaminant) detected" along with the other qualitative
and quantitative results as described earlier. In
such cases write "No claim" under the "Claim" column.
(5)
Notes
Any notes' regarding the description of the sample,
analysis, label, etc. made by the analyst should be
made in Item 11, if possible. Such notes should be
followed by the analyst's initials to indicate they
are his or her remarks, and should be hand initialed
on the final typed copies. The analyst's notes should
represent observations only, and not conclusions.
-------
VII-8
c.
Reporting of Check Analysis
If a check analysis or any other additional work is per-
formed on a sample by a second analyst, the results should
be headed by the designation "Check Analysis" or "Additional
Analysis," followed by the analyst's name and date reported.
The results should be reported according to the previously
described format, except that the "Claim" can be omitted
if stated previously in the report (see example in Appendix D).
The check or additional analysis can be reported on the same
page as the original analysis if there is enough room without
crowding. For most samples, however, a second manifold is
used, in which case only Item 1 need be filled out, followed
by the word "(continued)." Items 2 through 10 can be left
blank and the results reported in Item 11. The Establishment
Copy should be discarded before typing, as it is not necessary
if all the Establishment Copy information is on the first
manifold.
d.
Supervisor's Comments and Summary
Usually Item 12 is reserved for remarks or a summary made
by the laboratory supervisor. Statements made by the super-
visor should reflect or be based on observations and data
of the analyst.
The supervisor should provide a brief statement summarizing
the laboratory results for every potentially violative sample.
The relative percentage deficiency or overformulation is stated
so as to minimize the degree of variation from the label claims,
i.e. to give the producer the benefit of the doubt. Cross-con-
tamination should be summarized by quoting the lowest result
found along with the identity and means of confirmation.
Typical summarizing statements are as follows:
1.
Product is 11% deficient in malathion content.
2.
Product is 30% overformu1ated with respect to
thiram content.
3.
Product contains 0.2% parathion not declared on the
label. Confirmation by GLC (two different columns)
and TLC (two different eluting solvents).
4.
Product is 11% deficient in net contents for two
containers.
-------
.
VII-9
5.
Sub 1 is 15% deficient in toxaphene, sub 2 is 25%
deficient. No apparent difference in lot numbers
or physical appearance.
6.
Product is at least 16% deficient in meta1dehyde.
Some variation in results due to non-uniformity
of sample.
Any noteworthy conclusions based on the physical observations
(whether sample is chemically violative or not) should also be
stated, e.g.:
1.
Strong odor indicates decomposition has occurred.
2.
Product emulsifies poorly which could affect effi-
ciency.
3.
Non-homogeneity of sample may result in poor appli-
cation.
4.
Improper design of applicator may lead to undue human
exposure.
Likewise, any conclusions based on the chemical results should
also be summarized, e.g.:
1.
Product appears to be 9% deficient in malathion
content, but cannot confirm due to interferences.
2.
Although 7 to 11% deficient in 2,4-dichlorophenoxy
acetic acid, product is considered passed due to
non-uniformity of sample.
3.
Product appears to be 35% overformulated, however,
considered passed since interferences cannot be
definitely ruled out.
4.
Product consists of two phases, the top phase being
10% deficient in malathion, the bottom phase 14%
high in malathion. Malathion content of well mixed
sample (no emulsification noted) yields a chemically
satisfactory result for the sample as whole. No
directions for shaking or mixing noted on the label.
The supervisor1s name should be typed in Item 13 and the
name of the laboratory in Item 14.
-------
*
VII-IO
e.
Typing the Analytical Report
After the supervisor has added his or her comments and
reviewed the analyst1s portion of the report, it should
be typed.
When the typewritten manifold is received from the
typist, it is proofread through Item 11 by the analyst,
then initialed and dated, if correct, after his or her
name. Any notes or comments should also be initialed
by the analyst. The check analyst, if applicable, should
check his or her typed portion and initial accordingly.
Minor typographical errors in the bottom half of the report
for chemically non-violative samples can be neatly erased
or corrected by hand. Any errors in the top half of the
report of any sample (i.e. that part that is sent to the
establishment) or any errors at all in reports for poten-
tially violative samples should be carefully corrected on
the typewriter or the report should be retyped. The en-
tire report for potentially violative samples should be
very neat, showing no erasures, smudges or obvious correc-
tions. .
The supervisor then proofreads his or her remarks and scans
the entire report for overall neatness and correctness.
The supervisor should then sign in Item 13 and date stamp
all copies. The jacket cover and History of Official Sample
can also be dated at this time.
f.
Final Disposition of Report
The manifold is then torn apart and the copies distri-
buted as follows:
1.
The Sample Record Copy, Regional Office Copy and
Biological Lab Copy should be punched to fit the
sample jacket and inserted on top just above the
History of Official Sample.
2.
The Establishment Copy should be paper-clipped inside
the left-front cover of the jacket.
3.
The Laboratory Copy should be retained in the labora-
tory and stapled together with the Lab Work Copy, a
copy of the History of Official Sample, a copy of
the Co11ecton Report and any other notes, charts,
graphs, etc. related to the sample. Copies of any
correspondence related to the laboratory handling
of the sample should also be retained.
-------
VII-ll
The sample jacket should then be returned to the designated
Inspectional or Compliance Office, or if arrangements have
been previously made, to some other Regional or Headquarters
uni t.
g.
Labeling
A label review must be performed as part of the
investigation for every sample collected under
the authority of FIFRA, as amended. Thus the
laboratory may have occasion to prepare review
copies of the product label for inclusion on the
jacket. The following is provided as guidance
for proper label submission.
If the inspector submits a label obtained from a
label bin at a producer establishment, and the
label matches exactly that on the product (except
for code numbers or net contents), then this label
will be adequate for submission with the jacket.
When the label differs, or the inspector's identifi-
cation is incomplete or lacking, another copy of
original label should be prepared from the container(s)
and properly identified. Code number and net
contents differences should be noted (with initials
and date) on the margins of the photocopy or photo-
graph, or in a note attached to the mounting paper.
Identification consists of sample number, date,
and initials of the preparer somewhere on the
label or copy surface so as not to cover up any
wording.
Labeling may be submitted either as an original,
as photographs, as a photocopy, as a typed copy,
or a hand-written copy.
(1)
If an original label from a container is
submitted, a copy should be made to replace
the original on the container. If metal,
cans have to be cut up for submission due to
poor printing contrast, the corners should
be rounded and the edges covered with heavy
tape. If there is an odor associated with
the label that can't be removed, the label(s)
should be inserted in a transparent polyethylene
bag and sealed with tape. All parts and
panels should have their location on the
original container indicated, such as "top,"
"right side," "front," etc.
-------
IIiI
VII -12
(2)
Photocopies and photographs may be submitted as
long as all portions of the label are legible.
Small or difficult to reproduce areas may be typed
out separately or filled in by hand and initialed.
The "Danger" warnings, skull and crossbones and
background are to be identified as to their color
for all Class "B" poisons.
It may be necessary to prepare a good photocopy
by cutting up the legible portions of several
photocopies and taping them together.
All photographs and photocopies should be mounted
with tape or staples to a sheet of heavy construc-
tion paper.
Each photograph or photocopy is to be identified
by ID number, date and analyst's initials.
a.
Suitable photographs may be obtained
with a Polaroid or other equivalent
instant camera using black and white or
color film. A close-up lens can be
used for smaller print, whereas a por-
trait lens can be used for larger print.
b.
In order to photocopy round contain-
ers a photocopier with a movable
table and fixed light source is
necessary. Apeco, Saxon and Savin
each manufacture models with this
feature. Round container copies
can usually be suitably prepared
by hand rolling or with the aid of
a ruler.
(3)
If it is impossible to submit an original, because
of very poor printing contrast, (e.g., silk-screened
glass jug), a typed or handwritten copy may be
submitted as long as it is properly identified.
Originals or copies of all inserts, advertising
literature and other related material asssociated
with the product should be identified and included
as part of the labeling.
-------
~
VII-13
When the labels are different for different size
containers (except for the size designation) or
different subsamp1es, all of the different labels
or copies should be submitted.
The nine basic components which should be present
on every product label are: (1) brand name, (2)
active ingredient statement, (3) precautionary
statement, (4) manufacturer's or distributor's
name and address, (5) directions for use, (6) net
contents, (7) assigned EPA Registration Number,
(8) Establishment Registration Number and (9) use
classification.
-------
. II
SCREENING
-------
VIII-l
VII 1.
SCREENING
INTRODUCTION
EPA Headquarters gui dance wi th respect to screeni ng for cross-
contami nat ion is reproduced in Appendi x E and shoul d be accepted as
the overall criteria by which to develop and maintain a screening
program. The following information is provided as supplementary
material to assist in the accomplishment of the screening function.
CHLORINATED HYDROCARBON SCREENING
Although AOAG 6.026 should be used to verify the presence of any
suspect chl ori nated hydrocarbon contami nat ion, it is preferable to
use commercially prepared TLC plates for day-to-day routine screening.
Aluminum oxide sheets (0.2 mm) of thin aluminum are available from
several suppliers (EM, Brinkman or Eastman). The fluorescent indi-
cator normally present does not affect the chromatography or detec-
tion and occasionally contributes to sample information. These sheets
can be easily cut into the desired size with shears or a paper cutter
to minimize waste.
Commerci alp 1 ates, after e 1 ut ion, are sprayed with a fresh 0.2%
silver nitrate solution in methanol, allowed to dry 5 to 10 minutes
and then exposed for at 1 east 1 hour under intense short-wave UV.
Observation should be made every 15 minutes.
Once identity of a cross-contaminant has been established, a
semi-quantitative estimate can be obtained from the spot intensity by
app lyi ng enough different standards amounts to bracket the sample
concentration.
-------
VIII-2
Among the chlorinated hydrocarbons that can easily be detected
and identified by TLC are: aldrin, dieldrin, heptachlor, chlordane,
(tech. and AG), toxaphene, DOT, TOE, Perthane, SHC, gamma SHC, endrin,
Ke 1 thane, Oactha 1, hexach 1 orobenzene, PCNS, ch 1 ortha 1 onil, erbon and
p-dichlorobenzene. Spots at or near the origin should be followed up
for suspect phenoxy herbicides.
Gas chromotography should be used, if possible, for both qualita-
tive and quantitative verification. If specific AOAC or standard
methods are applicable, they should be used, i.e., when the cross-con-
taminant is present in significant quantity or is the only ingredient
present. Since most of the technical chlorinated hydrocarbons consist
of several i somers or rel ated compounds, i dent ifi cat ion can usually
be definitely established by means of comparison of retention values
on at least two substantially different TLC solvents systems plus one
GLC column, or one TLC system and two different GLC columns. Several
alternate TLC solvent systems are given in AOAC 6.027(b).
A gas chromatograph equipped with a Coulson or Hall electrolytic
conduct i vi ty conductor and a vent i ng valve wi 11 produce a spec ifi c
response to ch 1 ori nated hydrocarbons in the presence of other non-
chlorinated pesticides. Solvent and major ingredient peaks should be
vented, if possible, to minimize contamination of the cell water. A
3% OV-l column operated at 1800 to 2100 will be adequate for most
situations. 3% XE-60 (OV-225) and 3% Carbowax 20M are also recommended
for confirmation purposes. A flame-ionization detector will generally
be adequate for analysis of contaminants present at greater than 0.1.%.
An electron-capture (EC) detector can also be used for chlorinated
hydrocarbon contami nant ana lys is. However, one must be very careful
in the interpretation of results, as the EC detector is not as speci-
fic and is more sensitive than the electrolytic conductivity detectors.
-------
VIII-3
For products formulated with technical chlordane or toxaphene,
TLC screening will normally only serve to confirm the identity of the
active ingredient, rather than provide any useful information regarding
contamination. However, the screening is still considered meaningful
since non-specific total chlorine assays are often employed for these
products.
Addit i ona 1 TLC 501 vent systems and re 1 at i ve retention data for
most chlorinated hydrocarbons can be found in the EPA Manual of Chemical
Methods for Pesticides and Devices and Volume VII of Analytical Methods
for Pesticides and Plant Growth Regulators by Sherma and Zweig. Likewise,
additional GLC data relative to contaminant identification and veri fica-
tion can be found in Volume VI of Analytical Methods for Pesticides
and Plant Growth Regulators.
ORGANOPHOSPHATE SCREENING
Screeni ng for organophosphates can be accompl i shed by several
techniques. In addition to the methods outlined in AOAC 29.022 (for
res i dues) and in the EPA Chemi st IS Manual, one may also emp 1 oy the
method recommended by McDaniel (NEIC-TLC-l) and adapted from J.O.A.C.
49 1171 (1966). Toluene should be substituted for benzene to minimize
the health hazard.
Pre-coated silica-gel plates with fluorescent indicator (EM
Silica Gel 60, F-254, 0.2 mm or equivalent) on aluminum or plastic
sheets are preferable to laboratory prepared plates. They are more
uniform and can be cut to different sizes as needed.
Parathion, methyl
phorate, ethion, EPN,
parathion, disulfoton, malathion, diazinon,
fenthion, coumophos and trithion all can be
detected wi th the referenced TLC systems.
A suspected spot noted at
the origin, when using benzene or toluene as eluting solvent, should
-------
VIII-4
be further investigated due to the possible presence of TEPP, dibrom,
dimethoate or mevinphos. Ethyl acetate is considered a good secondary
solvent for eluting organophosphate spots off of the origin. Elemental
sulfur will also show up as a spot in most of the described systems
at Rf = 0.8 or greater.
Gas chromatography using a thermionic or flame-photometric (FPD)
detector can be used as an organophosphate screeni ng procedure of
individual samples in addition to providing quantitation and qualita-
tive confirmation. Screening by GLC is not advisable for products
formu1 ated wi th organophosphates since the detector cou1 d become over-
loaded and contaminated.
A 3% OV-l co1 umn operated at 1800 is recommended for screeni ng,
using a 1-3 micro-liter injections. The sample is prepared by ex-
tracting 0.5 grams of sample with acetone. The range and attenuation
are adjusted to give 50% full scale deflection upon the injection of
1 nanogram of a typi ca 1 organophosphate such as parathi on. Any sample
peaks not present in the technical ingredient standard(s) giving at
least 50% deflection indicate possible contamination. This response
wi 11 represent a contami nat ion 1 eve 1 of about 0.01% for most organo-
phosphates of concern.
For qualitative confirmation, the parameters given above will
normally be adequate for most organophosphates. However, for quanti-
tat i ve purposes, the sample and standard concentrations must be ad-
justed to within 5% of each other to minimize non-linearity errors.
Positive confirmation for organophosphates is generally more
difficult than with chlorinated hydrocarbons, since most technical
materials consist of a single major compound. Thus, two distinct TLC
systems and two GLC columns should yield matched retention values to
-------
.
VIII-5
assure identification.
If identification
is in any way in doubt,
further confirmation should be obtained by other means such as IR or
mass spectroscopy.
If the contaminant is present at levels greater than 0.1%, an-
alysis can usually be accomplished by FID.
The EPA Chemist's Manual and Volumes VI and VII of Analytical
Methods for Pesticides and Plant Growth Regulators by Zweig and Sherma
list retention data for many TLC and GLC systems.
SCREENING FOR OTHER CLASSES OF PESTICIDES
At present there are no routine methods currently in use for
screening of other c1a~ses of pesticides. If such is desired, different
TLC systems are described by class in Volume VII of the previously
mentioned reference for: carbamates, triazine herbicides, nitrophenols,
substituted ureas and uracils, dithiocarbamates and phenoxyherbicides.
-------
.
INSTRUMENTATION
-------
IX-1
IX.
LABORATORY INSTRUMENTATION
INTRODUCTION
The pesticide product laboratory should maintain, at a mini-
mum. the following equipment in order to adequately respond to the
expected sampl e vari ety and to fully take advantage of contemporary
technical innovations. Quality assurance considerations dictate
that each laboratory be able to apply sta'te-of-the-art methodology--
which in today.s terms means full capability for gas chromatographic
and liquid chromatographic analysis. The quantities of each item
and different combinations available for balances, spectrophoto-
meters and chromatographs wi 11 be contingent on the number of an-
alysts, space allocation, fund availability. and overall sample
composition.
ANALYTICAL BALANCE
1.
Specifications - Single pan (mechanical or digital)
Precision: % 0.05 mg
Capacity: 160 to 200 grams
2.
Maintenance and Calibration
The balance shoul d be located as 1 eve 1 as poss i b 1 e in a
draft-free area on a heavy shockproof, braced tabl e or
bench top to minimize external interferences. Spills
should be cleaned up immediately, and the balance and
surrounding area cleaned up in general after each use.
Weights should not be left on the knife edge when the
balance is not in use, nor should the balance be set in
-------
II
IX-2
the "read" position before having located the final "rough
adjust" position. Weight adjusting knobs should be turned
slowly. The balance should be cleaned thoroughly and
calibrated at least annually (or as needed) by a factory
representative or authorized agent. The accuracy should
al so be checked every three months, or more often, if
necessary, by laboratory staff using NBS Class S cali-
brated wei ghts. A log book shoul d be retai ned for re-
cording of all maintenance and calibrations.
3.
Use
The analytical balance is used for all sample and stand-
ard weighings up to 10 grams. It will also be employed
for all other preparations where accuracy is necessary,
such as primary standard and titrating solutions.
TOP-LOADING BALANCE I
1.
Specifications - Mechanical or digital
Precision:
Capacity:
:t 0.005 gr.
1200 gr. (Tare optional)
2.
Maintenance and Calibration
Generally,
balance.
the same as
given above for the analytical
3.
Use
The top-loading balance should be used for analytical
wei ghi ngs over 10 grams and for net contents determi na-
tions within its capacity. This balance can also be
used for the preparati on of most 1 aboratory reagent so-
lutions.
-------
IX-3
TOP-LOADING BALANCE II (Optional)
1.
Specifications - Mechanical or digital, readable to
1 gram.
Precision:
Capacity:
:t 0.5 gram
3 kg (tare optional)
2.
Maintenance and Calibration
Same
as
given
previously
for the analytical
balance.
IOLM
standard
weights
are
satisfactory for calibration
above 200 grams.
3.
Use
Used for determination of net contents when gross weight
is over 1 kg.
Note:
Satisfactory digital top-loading balances are also
available that combine features of the high and low
loading balances described above.
pH/MILLIVOLT METER
1.
Speci fi cat ions Range: 0-14 pH uni ts or :t 1500 mv, accu-
racy: :t 0.01 pH unit or :t 1 mv, (:t 2000 mv range and
:t 0.1 mv accuracy, if specific ion analysis is to be per-
formed). The meter should accomodate common electrode
jacks and have temperature compensation capability.
Electrodes necessary for analysis of pesticide formula-
tion include the following: (1) standard calomel fiber
junction with saturated potassium chloride electrolyte,
(2) glass electrode (Fisher 13-639-3 or equivalent),
-------
IX-4
(3) silver billet (Corning 476065
combination pH/reference electrode.
(platinum. Orion 96-78 or equivalent).
or equivalent).
(5) combination
(4)
redox
Automatic titrating units are available that are also
satisfactory for routine laboratory use. These instru-
ments (Fisher. Mettler. and Brinkmann. and others) are
ava il ab 1 e with different degrees of automation from end-
point detection to automatic sample switching. The most
desirable feature of automatic titrators is the synchro-
nous recorder opt ion.
of the ~itration curve.
which will yield a permanent record
The acquisition of the automated titrator unit should be
cons i de red by those 1 aboratori es performi ng a hi gh volume
of titration samples; i.e.. at least SO/month. The ti-
trator unit will also serve as a routine pH meter. if
necessary.
2.
Maintenance and Calibration
The meter and electrodes
should be maintained according
to the manufacturer's recommendations.
Normally. the glass electrode and silver billet will be
left attached to the instrument as the chloride determin-
ation will be the most prevalent use.
These two e 1 ec-
trodes should be left standing in clean distilled water.
Periodically buff the silver billet tip with steel wool
to enhance response.
Titration curves should actually be plotted for suspected
violative samples and during reagent standardizations to
verify end-point consistency. In most routine cases.
-------
IX-S
however, the determi nat i on can be performed by t i trat i ng
in progressively smaller millivolt increments to a pre-
determined end-point value.
Buffers of pH = 3, 7, 10 should also be maintained for
purposes of accuracy
certain colorimetric
in pH measurements,
particularly for
determinations,
extraction steps and
HPLC mobile
as critical
phase adjustment. Exact
for pH or mv titrations,
calibration
is not
since
usually detec-
tion of the pH change at the end-point is all that is
important.
Combination pH and redox electrodes are more convenient
to use, and are just as accurate as dual electrode systems,
when these type of measurements and/or titrations need to
be performed.
3.
Use
As mentioned above, the pH/mi 11 i vo 1 t meter wi 11 most often
be used for the potent i ometri c determi nat i on of chl ori de
or bromide.
The hal ide
anion
may derive directly, as with the deter-
mination of quaternary ammonium compounds, or indirectly
after reduction of an organohalide with sodium, sodium
biphenyl,
Parr bomb or lime fusion.
The chi ef i nterfer-
ence will be sulfur or sulfide, which must be oxidized
to sulfate with hydrogen peroxide before halide titra-
tion can be accomplished. In most cases, chloride and
bromide can be determined individually in the presence
of each other by carefully plotting mv vs. volume. How-
ever, neither ion should be present in great excess over
-------
IX-6
the other, or on 1 y tota 1 ha 1 i de can be determi ned. The
resulting curve should be similiar to the illustrated in
Fi gure IX-I.
The pH meter will also be used for acid-base and redox
titrations.
Although
chromatic
chemical
indicators
are
specified in many written methods and will serve for
most general acid-base titrations, a potentiometric plot
should be accomplished whenever the solution being ti-
trated is suspected of bei ng buffered, or thought to con-
tain different species than claimed. A potentiometric
titration will be particularly useful in titrating two
or more speci es in a mi xture of di fferi ng pka or pkb
values; i.e., phosphoric acid in the presence of a min-
eral acid such as HCl [see Figure IX-2].
Specific ion electrodes have yet to find extensive use
in pesticide formulation analysis, however, this should
not preclude their use on an experimental basis.
INFRARED SPECTROPHOTOMETER
1.
Specifications
A research spectrophotometer is
pesticide formulation analysis.
not necessary for routine
However,
the
instrument
should be of double-beam/optical
nu 11 des i gn wi th grating
_1
optics and wavelength range of 4000 to 400 cm Ordinate
repeatability should be at least 1% of full scale with an
accuracy of f: 1% fu 11 scale. The chart paper gri d wi dth
(ordinate) should be at least 15 cm wide to ensure accurate
absorbance readi ngs to three s i gnifi cant fi gures. Ordi nate
and abscissa expansion are desirable, but not necessary op-
tions.
-------
~
I
I
I
I
I
I
I
I
I
I
A 15
mv
A = vol. eq. to Br-
C-A = vol. f::q. to Cl-
IX-7
Figure IX-l.
VolUlI1l! AgN03
Titration of Br- and Cl- with AgN03
[)
Voluille NaOH
Titration of HCl and H3P04 with NaOH
C-B = Vol. eq. to Hl04/3
C-B = B-A (calculated)
A = Vol. eq. to HCl
pH
A
,
.I
~
j
I
Figure IX-2.
C
-------
iI
IX-8
Matched potassium bromide cells should be available in
0.1, 0.2, 0.5, and 1.0 mm thicknesses. Potassium bromide
pellet apparatus (press, die, holder, etc.) may prove
useful on occasion for qualitative confirmation purposes.
2.
Maintenance and Calibration
Maintenance
and
routine
operation
should
be
performed
according to the manufacturer's recommendations.
Wavelength calibration should be checked at least once
every three months by means of a polystyrene film. Re-
producibility should be verified, at least for all poten-
tially violative samples analyzed by infrared, by repeating
the spec ifi ed wave 1 ength scan in dup 1 i cate for both the
sample and standard. The gain, slit program, sensitivity
and scanni ng speed are to be adj usted accordi ng to the
purpose of the particular scan; i. e., whether quantita-
tive or qualitative.
The cells should be stored, when not in use, in a desic-
cator cabinet with indicating silica gel. Moisture con-
tact with the cell surfaces is to be minimized with respect
to handling, quality of solvents used and exposure of the
cells to the atmosphere. After rinsing with solvent, the
cells should be dried by use of drying tube and vacuum line.
Care should be taken to prevent solvent from contacting
the rubber gasket that bi nds the celli n the holder. The
cells should be replaced when permanently fogged to the
point resolution is intolerable or transmission for the
blank cell(s) is less than 90%.
-------
IX-9
3.
Use
Many Official, Standard and other methods are available
utilizing IR techniques. For single component dusts, wet-
table powders and granules, IR is one of the most precise
methods available from a quantitative standpoint. The
relative precision for most tested IR methods is on the
order of i: 1%.
Infrared spectroscopy can also be utilized
to assay some
quite 1 imited
and pest i ci de
emulsifiable concentrates,
but
its
use is
for the ana lys is of low percentage
mi xtures.
liquids
Generally, for powder and granules, a single shake-out
for an hour fo 11 owed by fi 1 trat i on or centri fugat i on wi 11
prepare the sample for analysis. For liquid formulations,
an attempt is usually made to evaporate off as much so 1-
vent as possible by heating on a steam bath with a current
of air
prior to dilution; however, care must be taken to
that no active i ngredi ent is lost through evapor-
or decomposition. Chloroform and carbon disulfide
ensure
ation
have found the wi dest usage as tR solvents for quanti ta-
tive purposes, although acetonitrile, carbon tetrachloride
and acetone are also used for the extraction step and as
the spectrophotometric solvent. Carbon disulfide, how-
ever, is a very poor extracting solvent, so that extrac-
tion usually must be carried out with acetone or a carbon
disulfide-acetone (9:1 V/V) mixture. The extract is then
evaporated prior to redilution with carbon disulfide for IR
measurement.
-------
IX-I0
It
is desirable
to match the absorbance of the samp 1 e
and standard as closely as possible to minimize non-
linearity effects, although most written methods have
been verified for adherence to Beer's Law.
One must be
very cautious of dev i at ions from 1 i neari ty in regi ons of
the spectra where hydrogen or other i ntermo 1 ecul ar bond-
ing occurs, particularly in the near infrared.
ULTRA-VIOLET/VISIBLE SPECTROPHOTOMETER
1.
Specifi cat ions
Double beam, single monochromator, ratio and energy re-
cording.
Wavelength range:
Resolution:
190-3500 for UV/Vis./NIR
190-900 for UV/Vis.
0.2 mu at 220 nm
Photometric reproducibility:
0.5% Transmission
Wavelength accuracy:
0.4 nm, 1.5 nm, and 8 nm in the
UV, visible and near infrared,
respectively.
Variable scanning speeds:
1.8 to 1800 nm/min. depending
on range
Oridinate and Abscissa expansion:
optional
Source:
H2 discharge for measurements to 400 nm; Tungsten
filament for 360 nm and above.
Detector:
Photomultiplier for use to 700 nm
Lead sulfide cell for use above 360 nm
One cm matched
infrared
s il i ca cells can be used for
practically all routine determinations. Standard silica
ce 11 s shoul d be used when measuri ng absorption below 220
millimicrons.
0.1 cm silica cells may also be useful on
occasion but are not necessary.
-------
IX-ll
2.
Maintenance and Calibration
Ma i ntenance and ca 1i brat ion s hou 1 d be performed accord i ng
to the Operator's Manual. The wavelength and response for
a standard holmium oxide filter should be checked at
1 east once every 3 months or whenever there is doubt re-
garding instrument performance. Annual cleaning and cal-
ibration by a factory representative is also recommended.
Reproducibility should be checked in duplicate for all
potentially violative samples. and for all measurements
taken in the near infrared. The hydrogen di scharge 1 amp
shoul d not be 1 eft on any longer than necessary. as it
has a limited life span and is expensive to replace.
Every precaution should be taken when cleaning and han-
dling of the silica cells. Fingerprints. dust. deposits.
and moisture on the cell windows are to be avoided. For
cleaning purposes the cells should be rinsed with water
and methanol
and air-dried.
Acetone
should
be avoi ded
as any trace wi 11
strongly absorb in the UV Regi on.
If
enough sample or standard solution is available. the sample
cell may be prepared for individual measurements during an
analytical run by rinsing and discarding with solution to
be measured three times prior to filling the cell for anal-
ysis. In such cases it is preferable to start with the
weakest solution in a series and progress to the strongest.
3.
Use
There are several pesticide formulation methods available
ut il i zing the UV Regi on. fewer procedures that uti 1i ze the
visible region. and very few utilizing the near infrared
region. The accuracy and precision deteriorate as one
-------
IX-12
goes from UV to NIR, although the spectra become more
specific. Many compounds (both pesticides and inerts)
absorb in the UV region, thus any spectrophotometric re-
sults obtained should be carefully interpreted.
In the visible region, the results are generally more
specifi c but care must be taken to match sample and stand-
ard in absorption intensity or prepare a full calibration
curve; even though the concentration response curve may
be linear, it does not always pass through the origin.
One must be extremely careful in making measurements in
the near infrared; this is a relatively unstable spectro-
photometric region from both an instrumental and molecular
standpoint. If there is any. doubt concerning the analyt-
ical results, another analysis should be performed using
the infrared spectrophotometer or another method.
The response curve for most compounds in the near IR re-
gion is non-linear, or at best, linear over only a very
limited concentration range. Thus either the standard
and sample should be matched within 3% of each other, or
a complete calibration curve should be prepared.
Also,
since
most of the measurements made in the NIR
re-
gion result from the presence of an N-H moiety within the
molecule, as is the case with carbamates, co-extratives
will
due
have an unpredi ctab 1 e effect on the band i ntens i ty
to hydrogen bonding and other intermolecular forces.
If this situation appears to be the case, determinations
shoul d be made at two concentration 1 eve 1 s and the resul ts
compared.
I f there are
significant differences
between
the two results, an alternate procedure should be attempted.
-------
IX-13
For most spectrophotometric analyses, the following
ment parameters (or equivelent) wi 11 be optimum for
tative determinations in the UV region:
instru-
quanti-
Sensitivity:
Time constant:
Scanning speed:
Range:
Source:
Detector:
Scale expansion:
10
0.2
36 nm/minute
0-1% T; 0-IA
Hydrogen lamp
Photomultiplier Ix
Ix
The instrument shoul d be adjusted for 100% T at the wave-
1 ength of interest wi th reference so 1 vent in both cell s,
and for 0% T with the sample shutter beam closed. The ad-
justments should be repeated if a different (more sensi-
tive) range is going to be used. After the zero and 100% T
have been adjusted in the transmittance mode, the unit may
be switched to the absorbance mode. Usually, for UV deter-
mi nat ions, the absorpt ion is meas ured from 360 to 190 nm.
This serves as an indication if any interferences are pre-
sent and also allows determination of a good base point.
For use in the vi sib 1 e range the above settings shoul d be
retained, however, a tungsten source should be used instead
of hydrogen 1 amp and a scanni ng speed of 360 nm/mi n em-
ployed. The peak of interest should be scanned for at
1 east 100 mu on each side to verify that the measurement is
being taken at the maximum absorption point and not on an-
other peak shoulder. For use in the near infrared, the
tungsten lamp and lead sulfide detector cell should be
used.
GAS CHROMATOGRAPH
A gas chromatograph is an absolute necessity in the pesticide
formulation analytical laboratory. Although there are many
-------
IX-14
limitations to the technique and a lack of official methods
ut i 1 i zing gas chromatography, there are too many occas ions where
it offers the only specific and/or rapid method available.
The bas i c requi rements for the ana lys is of a pest i ci de by gas
chromatography are for the compound of interest to be somewhat
volatile and thermally stable.
1.
Specifi cat ions
There are many commercial gas chromatograph models avail-
able offering a wide selection of detection systems, column
configuration, programming capabilities, and data systems.
The basic considerations when making a selection, however,
are (1)
adaptability to
di fferent detector systems,
(2)
overall system response and reproducibility, (3) simplicity
of operation, (4) ease and availabil ity of maintenance and
serv ice, and (5) adapt i on to data systems and auto sam-
plers.
A research-ori ented instrument is not requi red for most
analytical needs, but at least one temperature programming
unit should be available in the laboratory. The column
oven should be stable to :t 0.2°C, and is a much more
critical factor than the absolute temperature itself,
although the latter figure should not vary by more than 5°C
from its true value. Electrometer and recorder (1 mv)
response should not vary by more than :t 0.5% each.
The following detectors are recommended for the pesticide
formulation laboratory as part of the overall gas chromatog-
raphic capability:
-------
IX-IS
(a)
Flame Ionization Detector (FID)
The flame ionization detector is currently the most
useful gas chromatographic detector to have available
in the pesticide formulation laboratory for routine
quantitative analysis. Its main features are: good
sensitivity, non-selectivity (responds to all com-
pounds except inorganic gases and water), and wide
linearity range. The FID is relatively insensitive to
minor thermal and flow fluctuations. The primary
disadvantages are that it destroys the sample compo-
nents duri ng detection, and that it requi res two ad-
ditional gases in addition to carrier. Nitrogen or
helium can be used as carrier.
A FID system should be maintained that is capable of
being used as either a dual flame ionization unit or
as two independent
wi 11 be rather rare
detectors. Dual flame operation
in the pesticide formulation lab-
distinctly different types of
oratory,
thus
two
columns can be maintained ready for use on each side
of the FID.
The dual-flame capability will only be
high sensitivity or the temperature
If two columns are to be used simulta-
required
for
programming.
neously,
however,
two separate el ectrometers
and re-
cording channels will be necessary.
A lthough not speci fi ca lly des i gned for thi s use, the
flame photometric detector can also be used as a flame
ionization detector.
However,
the
fl ame wi 11
be a
reducing flame rather than oxidizing, resulting in
less overall sensitivity and reduced linear range. A
solvent valve may be necessary for such usage, as any
injections over 1 microliter may extinguish the flame.
-------
IX-I6
Gases for FID operation are specified as 'follows:
Air
Best quality medical breathing air or
compressed air, both with filter-
driers. Compressed air may prove
to be unsatisfactory at very high
sensitivities, however.
Hydrogren --
Prepurified with filter-drier.
Carri er
99.99% helium or pre-purified nitrogen,
both with filter-driers.
(b)
Thermal Conductivity Detector (TCD)
If a flame 'ionization detector is not available for
quantitative analysis in the formulations laboratory,
the second choi ce is a thermal conduct i vi ty (or hot
wi re) detector. An advantage of the TCD is that it is
non-destructive; components may be collected from the
exit port for further analysis. The TCD is also
rather inexpensive and requires only carrier gas for
operation. Unfortunately, the recommended carrier gas
is helium, which is expensive and difficult to obtain
in some locations. The disadvantages of the TCD are
its lack of sensitivity and its relatively large re-
sponse to minor temperature and flow variations.
The TCD should be protected with an over-heating or
high-resistance switch to protect the detector from
damage at high temperatures, particularly. in the
presence of oxygen or highly-oxygenated compounds. A
TCD of low fi 1 ament channe 1 des i gn is also preferab 1 e
to minimize loss of resolution in the detector. This
-------
IX-17
will allow the use of 3.5 mm 1.D. columns at rela-
tively low flow rates.
Carrier
drier.
gas should be 99.99% helium with a filter
Pre-purifi ed hydrogen has also been used as
for the TCD, but is not recommended from a
carrier
safety standpoint.
(c)
Flame Photometric Detector (FPD)
The flame photometric detector (Me1par or Bendix) is
also a useful addition to the gas chromatographic
system in the pest i ci de product 1 aboratory. The de-
tector is specific for compounds containing either
sulfur or phosphorus dependi ng on the i nsta 11 ed fil-
ter. Although not used routinely for quantitative
purposes. the FPD is i nva 1 uab 1 e for cross contami na-
tion screening and for verifying the identity and
concentration of cross-contaminants.
There
is an occasional
use for the FPD for routine
samp 1 e assays when it is des i rab 1 e to selectively de-
tect an organophosphate or sulfur containing pesticide
in the presence of oi 1 s or other i nterferi ng materi a 1 s
without resorting to clean-up procedures.
If possible, both phosphorus and sulfur filters should
be mounted in separate photomultiplier tubes with dual
electrometer and recorder channels. The two detector
signals can then be monitored simultaneously.
Extreme caution should be taken if quantitative an-
alysis is being performed in the sulfur mode. Sulfur
response is 1 ogari thmi c rather 1 i near, so that it wi 11
-------
I X -18
be necessary to prepare a calibration curve or to
assure that sample and standard response are matched
within 2% of each other.
The FPD may be equi pped wi th a valve on the co 1 umn
exit to vent solvents and unwanted material.
The gases required for FPD operation are identical to
those for FID. except that oxygen may be needed for
fuel support. U.S.P. Oxygen with a filter drier per-
forms satisfactorily. Newer models do not require
oxygen.
(d)
Electrolytic Conductivity Detector
The pesticide formulation analytical laboratory should
also have available a gas chromatographic detector
specific for halogen response. Of the available de-
tectors that serve this purpose. microcoulometric.
electron capture ~nd electrolytic
electrolytic conductivity detector
the overall need.
conductivity.
the
(Ha 11 )
best fill s
Results from the electrolytic conductivity detector
are relatively easy to interpret and use of the de-
tector does not requ ire an NRC 1 i cense.
The electro-
lytic conductivity detector will be primarily used for
screening and verifying halogenated cross-contaminants.
Although the electrolytic conductivity detector is not
as sensitive as the electron-capture. this is not
particularly a drawback in formulation analysis. as
rare ly is there any interest in components present at
less than 50 ppm (0.005%).
-------
IX-19
The electrolytic detector can be modified to serve as
a ni trogen specifi c detector by the insertion of an
activated nickel wire and strontium hydroxide plug in
the quartz. tube.
Newer vers ions are equi pped wi th a
nickel combustion tube.
The electrolytic conductivity detection system should
be equi pped wi th a valve so that so 1 vents and other
undes i rab 1 eel uants can be vented to the atmosphere.
thus minimizing contamination of the cell solution.
On older model Coulson type detectors. by-pass carrier
gas should be available directly to the valve and
adjusted such that the flow rate through the cell is
not disturbed significantly when in the vent mode.
otherwise the siphon may be lost.
(e)
Miscellaneous Detectors
Other detectors that may fi nd occas i ona 1
use in the
e1ectron-
pesticide
analytical
1 aboratory
are
the
capture.
mJcrocou10metric
and thermionic
(or a 1 ka 1 i-
bead) detectors.
The electron capture (either Tritium or Nickel-63) or
microcou1metric (Dohrmann) could. if necessary. sub-
stitute for the electrolytic conductivity detector. as
all three are halogen specific. although e1ectron-
capture wi 11 a 1 so respond to many other atoms and
groups. The alkali bead detector can substitute for
either the flame-photometric (phosphorus mode) and/or
the electrolytic conductivity (nitrogen mode).
Specific information on the use. maintenance and
calibration of electron-capture and micro-cou10metric
detectors should be obtained from the manufacturer(s).
-------
IX-20
2.
Maintenance and Calibration
Mai ntenance of the gas chromatograph is too 1 engthy and
sophisticated to treat adequately here.
The Operator IS Manual for most instruments
maintenance and trouble shooting in some
resources in this field include:
treat preventive
deta il .
Other
(a)
EPA Manual of Analytical Quality Control for
Pesticides in Human and Environmental Media;
published
Research
by the Health Effects
Research
Laboratory,
Triangle Park, NC, 27711, and
(b)
Chromatographic Systems/Maintenance and Trouble
Shooting, Walker, J. Q. et al, Academic Press, N. Y.
1972.
The principal criteria as to whether or not the gas chro-
matograph is operating satisfactorily are the peak shape
and reproducibility of retention time and response. Ex-
cessive noise,
poor response,
and large so 1 vent peaks are
also causes for concern.
The gas chromatograph should be periodically checked
against a mixture of known compounds using a standardized
set of instrument parameters. A recommended audit pro-
cedure for the FID, FPD, NPD, and microconductimetric de-
tectors is given in Appendix F.
3.
Columns
The basic column inventory for pesticide formulation an-
alysis should include the following:
-------
IX-21
(a)
3% OV-1 (or eq.) on Chrom WHP 80/100 (glass)
2 m x 3.5 mm
(b)
3% OV-210 (or eq). or Chrom WHP 80/100 (glass)
2 m x 3.5 mm
(c)
3% OV-225 (or eq.) on Chrom WHP 80/100 (glass)
2 m x 3.5 mm
(d)
3% Carbowax 20M (or eq.) on Chrom WHP 80/100 (glass)
2 m x 3.5 mm
The fo 11 owi ng co 1 umns wi 11 also fi nd occas i ona 1 use in the
formulation laboratory.
(a)
(b)
3% OV-17 on Chrom WHP 80/100 (glass) 2 m x 3.5 mm
Poropak Q. or Chromosorb 101 80/100 (glass) 2 m x 3.5 m
Although many other columns are listed in the pesticide
formulation literature, usually one of the above columns
will be equivalent.
The OV and SP phases are qui te su-
perior, from a thermal stability and consistency standpoint,
to the older phases listed in the literature.
It is recommended that the columns 1 i sted in II Report of the
Committee on Gas Chromatography of Pesticide Formulations"
[J.A.O.A.C. 50,420, (1976)] be employed to the degree
possible whenever developing new methodology.
Co 1 umns prepared for formul at i on use shoul d never be em-
ployed for residue analysi s due to possibi 1 ity of contam-
ination.
Stainless steel may be employed for the formulation analysis
of many pest i ci des, but boros i 1 i cate gl ass is preferred,
and is not that much more expensive for the advantages
-------
IX-22
gained. Glass is more inert, can easily be adapted for
on- co 1 umn injection, and is 1 ess 1 i ke ly to cause support
fragmentation. It is also easier to observe voids and
deterioration with glass columns. Bending of stainless
steel columns after packing can crush support material and
expose active sites which can lead to severe tailing
problems even on new columns.
All columns should be conditioned and operated according to
standard gas chromatographic technique. One must be cau-
t i ous when ra is i ng the co 1 umn oven temperature so as not
to exceed the temperature maximum of other columns in the
oven: The outside of the column oven should be clearly
marked as to what columns are on each injection port and
the date they were installed.
It is recommended that each laboratory buy pre-coated
column packings in a fairly large quantity (i.e., 50 grams)
to save time and eliminate variability from column to
co 1 umn. App 1 i ed Sci ence, Anal abs, Supe 1 co, and A 1 tech all
sell most standard packings that are needed for pesticide
product work. Speci a 1 ty columns and new packi ngs can be
prepared in the laboratory, however, using fluidizer,
rotary evaporation, or other standard technique.
A column should be abandoned and repacked when evidence of
deterioration appears such
severe tailing. Generally,
improved chromatography in
while.
as non-reproducibility and
silylating techniques have not
such cases so as to be worth-
4.
Typical Analysis
(a)
External Standard Method - A typical routine external
-------
IX-23
standard
tography,
described
quantitative determination by gas chroma-
ut il i zi ng the FID, may be accompl i shed as
be 1 ow.
Approximately 25 mg of standard (ca. 1 drop for
liquids) should be weighed out to the nearest tenth of
a milligram in a 25 ml volumetric flask, dissolved in,
and diluted to volume with acetone or other suitable
solvent. This will yield a final
tration of ca. 1 mg/ml.
standard
concen-
Enough sample (according to the label claim) should be
weighed out so as to match the standard concentration
as closely as possible for a 25 ml final volume.
Liquids may be diluted directly in a volumetric flask.
$01 ids shoul d be shaken out for at 1 east one hour on a
reciprocating shaker or ultra-sonicated for 20 min.
after addition of 25 ml of acetone by pipet. A 50 ml
screw-top erlenmeyer flask with a Poly-seal cap is
recommended. After shaking or ultra-sonicating, the
extracted material should be filtered (avoiding evap-
oration) or centrifuged for several minutes to yield
clear supernatant. One of the columns listed earlier
should be selected for analysis, usually either the 3%
OV-1 or 3% OV-225. accordi ng to the nature of the
material being analyzed. The column oven temperature
should be adjusted to give elution of the desired
component in 4 to 5 mi nutes, if poss i b 1 e. Many pes-
ticides elute satisfactorily in the temperature range
180 to 220°C. If a specific or appropriate method is
not available, the relative retention times for many
pesticides can be found in the following references:
-------
IX-24
(1)
Analytical Methods for Pesticides and Plant
Growth Regulations, Vol. VI Gas Chromatographic
Analysis, Ed. by G. Zweig, Academic Press N.Y.
(2)
EPA Manual of Quality Control for Pesticides in
Human and Environmental Media, published by the
Health Effects Laboratory Research Laboratory,
Research Triangle Park, N.C. 27711.
(3)
FDA Pesticide Analytical Manual,
U.S. Dept. HEW, Food and Drug
published
by
Administration,
Appendix to Volumne I, Transmittal 79-1.
The injection port temperature is maintained at least
10°C, but not more than 25°C, above the co 1 umn oven
temperature. The FID temperature should be adjusted to
230 to 250°C. The carrier flow should be between 50
and 70 ml/min for ~-in column, hydrogen at about 40
ml/min and air at 350 to 400 ml/min. Three micro-
liters should be injected (by total injection tech-
nique) for both sample and standard. If the response
of the sample is significantly different (>5%) from
the standard, the sample (if apparently over-formulated)
or standard (if apparently deficient) should be di-
luted to establish a more equivalent response, rather
than the varying injection volume or attenuation. A
calibration curve may also be established by injecting
3 1J1 of various concentrations, which should include
at least one value on either side of the sample re-
sponse.
The input/output (or range/attenuation) should be ad-
justed to give 50 to 70% full scale recorder response.
Standard and sample should be injected alternately
-------
'"
IX-25
until each pair reproduce to within % 2% of each other.
The
output or attenuation should be used to adjust
recorder
response, if necessary, rather than the input
or range adjustment.
The retention times of sample and standard should also
be compared, and if there is any doubt as to thei r not
being identical, a spiked sample should be injected.
Two peaks or a visible shoulder will indicate that the
compounds are different.
Peak areas or peak heights should be averaged for the
samp 1 e and standard, and the percent active i ngredi ent
calculated as follows:
Response
sample
Response
standard
conc.
standard
conc.
sample
x % purity of std. = % active
i ngred.
x
(b)
Internal Standard Method
A typical internal standard analysis may be accom-
plished in a similar manner by adding an identical
amount of a previously prepared internal standard
solution to both sample and standard.
For 1 iquids,
10 ml
of i nterna 1
standard solution is
added to sample and standard previously weighed out in
a 25 ml volumetric flask; the solutions are then di-
luted
to
the mark
for GC
analysis.
The internal
standard generally needs to be in a more concentrated
form to account for this dilution.
For dusts, powders and granul es, the i nterna 1 standard
solution is used as the extracting solvent. In this
-------
..
IX-26
case, the standard for the assayed ingredient should
be diluted by pipet in a screw-top flask to minimize
volumetric error that would occur by diluting lito
volume" in a volumetric flask.
The i nterna 1 standard response shoul d be wi thi n :t 1.%
for sample and standard, or else the sample/standard
should be reprepared and/or the sample should be
checked for an internal standard co-eluter. In the
latter case,
a different internal
standard shoul d be
selected or an external standard method employed.
It
is
recommended
that
a
non-pest i ci de
internal
standard be selected when developing new methodology.
This
wi 11
minimize
cross
contaminant
interference,
minimize handling of concentrated toxic pesticides and
save valuable standard material. Some typical reten-
tion times for suggested internal standards are given
in Table IX-I.
The percent active ingredient for an internal standard
method can be manually calculated as follows:
Adjusted sample response = sample response x
internal std.
response
(standard)
internal std.
response (sample)
Adjusted sample response
Standard response
conc. std
x x % purity of std. =
conc. sample % active ingred.
HIGH-PERFORMANCE LIQUID CHROMATOGRAPH
Although high-performance liquid chromatography (HPLC) is a
relatively new quantitative technique, many published methods for
-------
Tab 1 e I X-l IX- 27
tION-PESTICIDE INTERNAL STANDARD RETENTION TH1ES
Column: 3~ OV-1 on Chrom HHP 8011 nn 6 I X 4 rrm ID (glass)
Carrier: N2-6n m1/min.
1400C 160"C l!)O<'C 20ncc
RT RRT* RT RRT* RT RRT* RT RRT*
p-Bromopheno1 1.2 0.08
Biphenyl 1. 85 0.12 0.9 0.10
Dimethyl Phthalate 2.45 0.16 1.2 n.13 n.7 0.16
Diethy1 Phthalate 4.7 0.30 2.0 0.22 1."15 0.24
Benzophenone 5.4 0.35 2.4 0.27 1.25 0.29
Dipropyl Phthalate 9.0 0.45 3.4 0.44 1.7 .0.47 0.9 0.50
Benzyl Benzoate 9.9 0.63 4.0 0.44 2.1) 0.47 1.1 0.51
Aldrin 15.65 1.00 9.0 1.00 4.3 1.")0 2.15 1.00
[I i isobutyl Phthalate 16.15 1.03 6.05 0.67 2.7 0.63 1.4 0.65
Dibuty1 Phthalate 8.7 0.97 3.7 0.86 1.8 0.84
Triphenylmethane . 9.8 1.09 4.35 1. 01 2.2 1.02
Di pen ty1 Phthalate 18.7 2.08 7.3 1. 70 3.3 1. 53
Dipheny1 Phthalate 21.6 6.00 8.4 4.67
Diocty1 Phthalate 11. 9 5.53
Column: 3% OV-225 on Supe1coport rJ/100 6' x 4 mm 1D (glass)
RT RRT* RT RRr* RT RRT* RT RRT*
p-Bromopheno1 6.2 0.31 2.6 0.33 1.3 0.34 0.7 0.39
Biphenyl 2.2 0.11 1.0 0.13 0.6 0.16
[)imethyl Phthalate 6.6 0.33 2.75 0.34 1.4 0.37 0.7 0.39
[)iethy1 Phthalate 10.8 0.54 4.3 0.54 2.0 0.53 1.0 0.56
Benzophenone 11.6 0.58 4.8 0.60 2.3 0.61 1.1 0.61
Benzyl Benzoate 19.3 0.97 7.4 0.93 3.3 0.87 1.6 0.89
l\ldrin 20.0 1.00 8.0 1. 00 3.8 1. no 1.8 LOt)
Di i sobu ty1 Phtha 1 ate 28.7 1.44 10.1 1.26 4.2 1.11 1.8 1.0'1
Oipropy1 Phthalate 22.3 1. 12 8.1 1.01 3.4 0.89 1.6 0.89
Oibutyl Phthalate 16.0 2.0 6.3 1.66 2.7 1. 50
.riphenylmethane 14.13 1.135 6.1 1.61 2.7 1. 50
[);pentyl Phthalate 32.4 4.05 11.135 3.12 4.75 2.64
Diocty1 Phthalate 36.4 9.513 12.8 7.11
-------
IX-28
formulation analysis are now available. HPLC appears to be the
dominant trend in the field of formulation analysis and most new
methodology utilizes the technique. HPLC has the advantage over
GC in that non-volatile compounds lend themselves to direct an-
alysis (without derivatization) and that thermally labile com-
pounds can be easily chromatographed. The disadvantages are
high cost, non-uniformity of column technology and large amounts
of spent solvents to dispose of. HPLC still finds only limited
use in the residue area due to detector limitations.
1.
5pecifi cat ions
A full purpose liquid chromatograph for the formulation
laboratory should be equipped for dual solvent gradient
operation. With the wide variation in columns available,
particularly reverse phases, the gradient capability will
help considerably in establishing the ideal mobile phase
compos it ion. 501 vent compos it i on will often need to be
varied from that given in referenced methods, particularly
when the column is not exactly the same as that specified.
The gradient should be capable of reproducing retention
times to within 1% for like injections so that analyses can
be conducted directly in the gradient mode.
The 1 iquid chromatograph should be equipped with either a
fixed-loop injector or autosampler for maximum reproduc-
ibility of injection for formulation analysis. With form-
ulation analyses, it is usually very easy to adjust sample
and/or standard concentration to adapt to a 5 or 10 micro-
1 iter loop. If both residue and formulation analyses are
to be performed on the same instrument, it will probably be
more pract i ca 1 to utili ze a syri nge or some other vari ab 1 e
type i nj ector.
-------
IX-29
The chromatograph should also be equipped with a variable
wavelength UV detector. The variable wavelength option
will allow for maximum sensitivity and for "tuning out" of
potential interferences. A continuous (200 to 700 nm)
wavelength detector is ideal, but the multiple wavelength
type with 30 nm interval filters will also be satisfactory
for most cases. The detector should produce minimal drift
in the i socrat i c mode. and possess a 104 1 i near dynami c
range wi th 1 or 10 mV recorder output. The refractive index
detector has not found wide use in the pesticide formu-
lation laboratory.
A column oven or water-jacket is recommended whenever there
is appreciable variation in ambient temperature or there
are instrument heating effects. Column temperature regu-
1 at ion is also necessary for worki ng wi th i on-exchange and
gel exclusion packings. The solvent-flow rate should be
adjustable to at least 0.1 ml/min and be capable of pro-
ducing at least 5 ml/min with analytical grade columns and
15 ml/min for preparative grade columns.
2.
Maintenance and Calibration
Preventive maintenance trouble shooting should be performed
according to the manufacturer's recommendations. The most
important maintenance requi rements are 1 ubri cat i on of mech-
anical parts and periodic replacement or cleaning of the
in-line filters. The loop injector will also require pe-
riodical adjustment to prevent leakage due to wear.
Corrosive mobile phase such as acids and bases should not
be allowed to stand on the instrument when not in use.
-------
IX-3D
Aci di c and bas i c mobil e phases can hasten deteri orat i on of
analytical reverse phase columns and stainless steel lines
if allowed to sit in contact for extended periods of time.
Care must also be taken when us i ng reverse phase columns to
avoid precipitating any of the sample ingredients, as com-
pounds of interest may be lost or the column can become
plugged. When changi ng from one solvent to another that is
immiscible with the first, an intermediate solvent should
first be flushed through the system to eliminate the last
traces of the initial solvent. Acetone and p-dioxane are
considered good solvents for this purpose.
A calibration mixture should be established for each column
that can be analyzed peri odi ca lly or whenever mal funct ion
is suspected. A suggested phthalate mixture and HPLC con-
ditions for a C18 Bondapak (Waters) are given in Appendix
F, Tab 1 eLl nject i on of such a ca 1 i brat ion mi xture will
assure proper response and separation when actual samples
are analyzed. Such cali brat ion injections shoul d be re-
corded in the instrument logbook.
3.
Typical Analysis
In practice, a typical HPLC analysis will closely parallel
a gas chromatographic
analysis.
There are two distinct
differences, however, that must be kept in mi nd, (1) to
improve GC separation, a change is generally made in the
column and/or temperature, whereas in most cases during
1 i quid chromatography a change wi 11 be made in the mobil e
phase. A column change is generally a last resort. (2)
The UV detector response for HPLC wi 11 vary considerably
from compound to compound, whereas, response wi th the GC/
FID system, there is relatively little response change from
compound to compound.
-------
IX-31
A good introduction to HPLC analysis of pesticides (both
formulations and residues) can be found in:
Analytical Methods for Pesticides and Plant Growth
Regulators, Vol. VII, Ed. by G. Zweig and J. Sherma,
Academic Press, N.Y.
With few exceptions, most pesticide formulation methods
today are being carried out on reverse phase micropartic-
ulate columns. These columns offer good resolution for a
wi de range of polar and non-polar compounds. Aci di c and
basic pesticides can be analyzed in most cases directly by
extraction and/or dilution using a paired ion in the mobile
phase.
As in GC, the i nterna 1 standard method shoul d be utili zed
whenever app 1 i cab 1 e although wi th loop injectors, the need
is minimized. Also it is desirable to use non-pesticide
internal standards; however, such compounds with known re-
tention values for HPLC are not as available as for GC.
Thus, it may take cons i derab le scouting to come up wi th a
good non-pesticide internal standard for a lot of pesti-
cides. Some suggested non-pesticide internal standards are
given in Table IX-2.
Norma l1y, the i nterna 1 standard can be made up in concen-
trated form in either the particular mobile phase to be
used or one of the make-up solvents. Identical amounts of
internal standard can then be added to both standard sample
extract (or dilution) as done for GLC.
Extraction of active
ingredients from solid matrices usually is
shake-out and/or ultrasonic treatment with
effected by
one of the
mobile phase solvents, or at a minimum a solvent that is
miscible in the mobile phase and of low UV absorptivity at
-------
IX-32
Table IX-2
HPLC INTERNAL STANDARDS
RETENTION TIMES IN MINUTES
REVERSE PHASE MEOH/H20 VARIAN 5000 ON MCH-10 @ 2m1/m;n 254 nm
Internal % Mohi1e Phase as MeOH/HzO
Std. 100/0 85/1~ 75/25 65/35 60/40 50/50 40/60 25175
Phenol 1.40 1.60 1. 70 2.18 2.95 4.15 7.48
Dimethyl
Phthalate 1.57 1. 70 2.10 2.70 3.10 5.30 11 . 50
Acetophenone 1.65 1.83 2.20 2.90 3.30 5.05 9.40
p-Bromopheno1 1.50 1. 71 2.25 3.20 3.83 6.75 13.61
Diethy1
Phthalate 1.60 1.95 2.60 4.35 5.50 12.30
Benzophenone 1.80 2.25 ' 3.45 6.50 8.80 20.90
Benzyl
Benzoate 1.90 2.70 4.95 11 .83 17.75
Biphenyl 1. 91 2.95 5.80 13.35 19.70
Diisobuty1-
phthalate 1.60 2.70 5.80 17.38 29.15
Dibutyl
Phthalate 1.81 2.94 6.30 19.45 33.5
Tripheny1-
methane 1.90 4.40 10.45 39.7
D;pentyl
Phthalate 1. 95 3.85 11 .95
m-Diphenoxy-
benzene 2.05 4.35 12.60
Diocty1
Phthalate 2.33 12.6
-------
IX-33
the analytical wavelength. If relatively
bases are necessary for extraction, then
centrifuged extract shoul d be neutral i zed
tion.
strong aci ds or
the fi 1 tered or
pri or to i njec-
For all extraction solutions, it is a good idea to filter
the sample through at least a 0.2 IJ filter prior to in-
jection to minimize clogging of the column (and pre-column
filter). Metricel (Gelman) filters (0.2 micron) or equiv-
alent work very well with most organic solvents;
they are
available to fit a 13 mm Swinny adaptor for quick filtra-
tion with a syringe.
The working range for most pesticides is in the 0.5 to 2
mg/ml which will generally yield mid-range 0.5 to 1.0 at-
tenuation (aufs) for a 10 IJ injection. For baits, plant
growth regul at ions and other low percentage formul at ions,
it may be necessary to go to a lower concentration and/or
increase sensitivity. The flow rate normally runs from 0.5
to 2.0 ml/min.
The wavelength ideally shoul d be adjusted
to an absorption peak for maximum sensitivity, reproduc-
ibility and specificity.
"End absorption", i. e., 220 nm or
lower may be necessary for some poorly absorbing material.
Most contemporary HPLC instruments will allow acceptable
quant i tat i ve ana 1 yses to be performed in the i socrat i c mode
by mixing solvent in situ, rather than having to pre-mix
solvents. Most instruments are also now capable of giving
good reproducible results in the gradient mode, however,
the analyst should be certain of obtaining at least as good
precision in the gradient mode as expected isocratically.
Standard and sample should be injected alternately until
duplicate injections reproduce to within z 1% for loop
-------
IX-34
injectors or % 2% for syringe injectors. Auto-injected
samples and standards should reproduce to within % 1%.
Response values for each of the two valid sample and
standard injections should be averaged and the percent
active ingredient calculated as given for GC analysis.
CHROMATOGRAPHIC DATA HANDLING
Various
techniques are available to measure
peak area from
the gas or 1 i qui d chromatograph.
as follows:
These techniques are
summarized
1.
Planimetry
The pl animeter is a mechani cal instrument used to measure
the area of any irregular shape. A baseline is extrap-
olated under the peak and the pointer, which attached to a
movable arm, is used to carefully trace the area of in-
terest. As the poi nter traverses the peak or peaks, a di al
and verni er drum wi 11 rotate. The difference between the
initial and final readings on the scales gives the area of
the peak( s). The method is somewhat t i me-consumi ng and can
yi e 1 d as much as % 5% error for small peaks. Reproduc-
ibility between analysts is poor. Precision can be im-
proved by tracing several times and taking an average.
This method is useful for measuring total response for
compounds such as chlordane, and toxaphene,
tronic integrator is not available.
if an elec-
2.
Height x Width and Half-Height
Si nce normal peaks approximate a tri angl e, one can approx-
imate the area by multiplying peak height by the width at
-------
IX-35
the half-height. The baseline needs to be extrapolated.
Thi s method is not very good for peaks that s i gnifi cant ly
tail, are poorly resolved, or are rider peaks. For good
gaussian-shaped peaks, this method is fast and simple. If
half-height widths are. identical for sample and standard,
thei r peak hei ght alone can be used.
be improved by increasing chart speed.
Width measurement can
3.
Triangulation
For gaussian-shaped peaks, the area of the triangle formed
by the baseline and tangents at the inflection points is
equa 1 to hei ght x 1/2 base wi dth. Thi s method is more t i me-
consuming than height x width at half-height, but is as
accurate if peak shape allows significant measurements.
4.
Cut and Weigh
Peak areas are measured by cutting out the chromatographic
peak and weighing on an analytical balance. An extrap-
olated baseline is required. Thickness and moisture con-
tent of paper must be constant. This method is time-
consuming and destroys the chromatogram (unless photocopies
are cut up), but is fairly precise.
5.
Disc Integrator
Thi s type of integrator operates from the output of the re-
corder-servo system, and is also coupled to the chart move-
ment. The area of a gi ven peak is proport i ona 1 to the
product of these two parameters and is obtained by counting
the total number of oscillations, which are recorded di-
rectly on the chart paper.
Extrapolated baselines must be
corrected for by proportional readings on either side of
-------
IX-36
the peak. One can obtain high precision and accuracy for
well-resolved peaks, but the technique is somewhat time-
consuming. Good reproducibility can be obtained between
analysts.
6.
Electronic Integrator/Computer
The chromatograph i c signa 1 is fed into a vo 1 tage to fre-
quency converter (or an analog to digital converter) which
generates
an output pul se rate proportional
to the peak
area. Thi s method is very preci se, qui ck, and accurate.
Generally no attenuation is needed, as lIoff-scaleli peaks
can be accurately measured. This technique also ties in
effectively with data storage capability. The technique
requires relatively expensive equipment and a high degree of
operator skill. It is recommended that the integrator stop-
and-start be refl ected by markers on the chromatogram so as
to be able to "see" what is being integrated. It is also
important to know what kind of baseline the integrator is
using for any given peak.
Integrators vary from very simple lIadd-onli modules that
simply yield an area measurement to those that will cal-
cul ate answers accordi ng to pre-programmed methods. Data
systems are available today that will also store peak in-
formation for recalculation or other future manipulation(s).
If BASIC capability is available, one can program standard
deviation and/or deviation from label claim. Printer-
plotters are also now available that combine
integrator and programming modes all in one module.
recorder,
Table IX-3 shows the precision expected out of the various
integration techniques.
-------
IX-37
Table IX-3
PRECISION OF VARIOUS INTEGRATION TECHNIQUES
Type
Precision
Height times half-height 3%
Triangulation 4%
Cut and Weigh 2%
Planimeter 4%
@ 1.%
DISC Integrator
Electronic Integrator 0.5%
Computer 0.5% and better
Peak Height 1-4%
-------
REFERENCE STANDARDS
-------
X-I
x.
REFERENCE STANDARDS
INTRODUCTION
Analytical reference standards should be maintained at the labo-
ratory for all normally encountered pesticides. It is also desirable,
but not necessary, to maintain standards of as many inert ingredients,
decomposition products and by-products as possible.
Both analytical and technical grades (if different) of pesticide
standards should be retained. Analytical grade standards of known
purity will be required for most assay procedures, whereas technical
grade material will be necessary for cross-contamination screening
purposes. The technical grade standard will usually allow identifi-
cation of normal by-products so that they won't be mistaken for cross-
contami nants.
SOURCES
Possible sources of pesticide standards and related materials
include the following:
1.
U.S. Environmental Protection Agency
Office of Toxic Substances, OPP Benefits & Field Studies
Division, CBIB Chemistry Laboratory, Bldg. 306, ARC-East
Beltsville, MD 20705 (P.rimarily for formulation analysis)
2. Qual ity .Assurance Section Analytical Chemistry Branch,
ETD/HERL (MD-69) U.S. Environmental Protection Agency
Research Triangle Park, NC 27711 (Primarily for residue
analysis, catalog available)
-------
X-2
3.
Basic manufacturers.
4.
Private commercial sources Chem Service, Applied Science,
Po 1 y Sc i ence, Nanogen and chemi ca 1 reagent sources (Eastman,
Baker, etc.)
The EPA Beltsville Chemistry Laboratory should be considered as
the primary source for technical and analytical standards for pesti-
cide formulation analysis. Many of their standards have been indepen-
dently assayed, either by differential scanning calorimetry or by
assay against other reliable primary standards. Quantities are usually
adequate for formulation analysis, although some standards are always
in short supply. There is no charge for their service.
The EPA Triangle Park (RTP) primarily
metabolite standards for residue analysis.
but the standards are quite reliable.
free of charge.
provides pesticide and related
Quantities are very limited,
All standards are provided
Standards from the basic manufacturer are usually reliable, how-
ever, quality assurance considerations dictate that their purity should
be confirmed, whenever possible, by independent assay, normally against
EPA Beltsville or RTP standards.
their materials free of charge.
Most companies provide standards of
Standards from commercial supply houses should only be obtained
as a last resort, and used with a great deal of care. These standards
should be independently assayed whenever possible. Shelf stocks of
these materials should be replaced when other sources become available.
Technical material is often sold as analytical grade. The cost of
standards from these sources can be exorbitant. However, commercial
sources may be the only recourse for some chemicals.
-------
X-3
Storage
All technical and analytical standards should be retained under
custody conditions as done for official samples, i.e. under lock and
key with controlled access.
Standards shoul d be i nventori ed by card fi 1 e or log book showi ng
compound, type, source, date of acqui sit ion, puri ty, date of puri ty
determination and any other significant information regarding the
standard.
Organophosphates and other labile/volatile standards should be
kept refri gerated (2-4°C). The refri gerator can be equipped with a
hasp and padlock or special locking device. The refrigerator may
also be placed in a controlled access storage area. Other pesticides
may be kept in refri gerator, if space permi ts, or kept at ambi ent
temperature. Freezing should be discouraged due to condensation and
frost problems.
Even upon refri gerat ion, however,
standards shoul d
be allowed to equilibrate to ambient temperature before opening the
container to minimize condensation.
Non-refrigerated standard storage areas should be directly vented.
A storage cabinet with a duct to an external blower provides an adequate-
ly ventilated storage area. Most cabinets can also be easily locked
for custody purposes.
Diluted analytical standards propared for quantitative analysis
should be retained for no longer than 1 month. Qualitative technical
standards prepared primarily for TLC cross-contamination screening (1
and 10 mg/~l in acetone) can be kept for up to one year unless decompo-
sition is evident. Both quantitative and qualitative solutions can
be stored at ambient temperature.
-------
X-4
Any retained diluted standards should be labeled as to ingredient,
solvent, concentration, and date of preparation. Fresh standard solutions
are always to be prepared when verifying results on potentially violative
samples.
REPLACEMENT
Organophosphates and other 1 abi 1 e compounds shoul d be replaced
or reassayed every two years, unless prior decomposition is evident.
Other pesticides can be kept for up to 4 years before replacement or
reassay. If reassay indicates decompositon of more than 2% relative
then the standard should be replaced.
Table X-l contains a list of 50 common pesticides that are recom-
mended for replacement every 2 or 4 years according to type. Any
other routinely used pesticide standard should also be replaced or
reassayed in this time period. Other less commonly encountered chemi-
cals are to be replaced or reassayed only on verifying results for a
defective samples.
-------
II
X-5
Table
X-I
Pest i ci de
Reference
Standards
1. p-tert-Amylphenol 26. Malathion
2. Atrazine 27. MCPA
3. o-Benzyl-p-chlorophenol 28. Mecroprop
4. Bromaci 1 29. Methyl Parathion
5. Captan 30. Mevinphos
6. Carbaryl 31. MGK-264
7. Carbofuran 32. Monuron
8. Chlordane 33. Naled
9. Ch 1 orpyri fos 34. Paraquat
10. Crotoxyphos 35. Parathion
11. 2,4-D 36. Pentachlorophenol
12. 2,4-D, butoxyethanol ester 37. o-Phenylphenol
13. Dacthal 38. Piperonyl Butoxide
14. Diazinon 39. Propoxur
15. Dicamba 40. Pyrethrins
16. Dichlorvos 41. Resmethrin
17. Dicofol 42. Ronnel
18. Dimethoate 43. Rotenone
19. Dinocap 44. Silvex
20. Diphacinone 45. Strychnine
21. Disulfoton 46. 2,4,5-T
22. Endrin 47. Toxaphene
23. EPN 48. Trichlorofon
24. Heptachlor 49. Trifluralin
25. Lindane 50. Warfarin
-------
APPENDIX A
HISTORY OF OFFICIAL PRODUCT
-------
I. $AMPLE: NIJ"'H<:R 2. "!:.(,ISTRII TION NUMB;::F,
HISTORY OF OFFICIAL SAMPLE -LODOO/ 75''2.0-313
3. PRODUCT
Ply - A~ 411
, f
4. LABORIITORY J:> t 11 " e Y"
S. DATE RECEIVEO ,.. , .. , ,
6. RECEIVEO BY So.l lJ t. P e..1 ,,'a..
7. RECEIVEO FROM ~""O""'" F"'.",,,,,,,,,,
.Dtl. ~.IYIS C'-
, p~ tl~lJ- .
B. SENT VIA C r'O""'"
,
9. SAMPLE CONOITION Ole
10. CONOITION OF SEALS ~J,j
11. SEALED BY f> b~feW\ h Fns be.e
12. OATE SEALEO «;"11- (.c,
,13. PIECES RECEIVEO I \£ \
14. PLACE STOREO S-l
I A\u~~ (;tt. Jk
. 15. ASSIGNEO BY
I
16. ASSIGNEO TO (~ Q.l+~" $~t\
17. OELIVEREO BY fA A.\ Tc. V' ~~-tt
lB. OATE OELIVEREO ~-'-~la
19.NUMBER SUBS RECEIVEO \
20. SUBS ANALYZEO (
21. OATE SEAL. BROKEN Co-t~-~(.
22. OATE RESEAL.EO (.-l \.. '- (,
n. RESEALEO BY l)~\\-~ ~ CA-H-
24. PLACE STORED 4-lf--
.ZS. OATE JACKET SENT OUT
26. REMARKS
,
EPA Form 3S40.17 (12'73~
A-l
REPLACES PR FOF:" 1-136 WHICH IS OBSOL.ETE.
-------
1. SAMPLE NUMBER 123~'~~": 19BfR
HISTORY OF OFFICIAL SAMPLE ""'()Ol
3. PRODUCT l~st,l,'1l
tJ,pt o",t
4. LABORATORY ~4" Fy~....t t~c.c C ~ V'V ~If,t
S. DATE RECEIVED 1- 1- ., 7 1-1."'17
6. RECEIVED BY C'6.~" KfJ'- /1. ~ t,J.}(
7. RECEIVED FROM LIQ'IJ ,) 1)'1 cL l/, ~ S, be.1. I....s 4\Ift.
, . ,). ;.S,
8. SENT VIA J I...,. A.
9. SAMPLE CONDITION '.,fa t>\<.
L ee.. /:" N,
10. CONDITION OF SEALS O/<. 0"
11. SEALED BY LJavL (J ."J Df.~~\ S~l!.
, ,
12. DATE SEALED 1- i.-, '1 ;-/1"'1
I 3. PIECES RECEIVED "')('1 I~ 4-
14. PLACE STORED ~-J (;,.,0" -1; ~£,p
, S. ASSIGNED BY f('\"IM4 L4wr."~ 1=l.1( U\(.A ~ Vp.C8 A,iJ. ,vi InfdJ..~'
16. ASSIGNED TO tJf; I D;, I Jr'"/'". ~ t~...~\ ~ ~,,~ " 'j
17. DELIVERED BY l~fj c.,'\.vl ~ " '1
CI"..1c.
18. DATE DELIVERED '7 - 7~ , '1 ; .., ~ -") 7 1-"')."')7
1 9. NUMBER SUBS REC EIVED +- 4- f
20. SUBS ANALYZED ;l I :;..
21. DATE SEAL BROKEN ., - 1\\ -1) 7-1 ,.., 7 7 .. ).. 'V1 ,
22. DATE RESEALED 1-,4"" ,- I 7 .. ., 7 r-~''''7
23. RESEALED BY ~fl'l Oif{J.~'.... 1)t."~;S rh.".u5 ,(,U ~t'J A"f~,,'
24. PLACE STORED ~ -~ ,-~ jr
2S. DATE JACKET SENT OUT 7- 11, "r7 ,- f-71
26. REMARKS C\\"~""";i 7..1.a-' 7
YU.. I.J.lJ'i4 ""$
EU.~ 1"~1
~,
~ C>~~ SA""'ita. \ l"'~"~ k T. \ \Ma SA c...e, ~.
A-2
EPA Form 3540.17 (12-73!
REPLACES PR FO~M 1.136 WHICH. IS OBSOLETE.
-------
APPENDIX B
OFFICIAL SEAL
-------
~ction 12: Sampling
3. Sealing of Sample
a. Preparing Sample
B-1
All official samples shall be sealed with official EPA
seals. Other samples should also be sealed when it is
likely that they will be used directly as evidence.
Samples may best be sealed by placing in an inverted
plastic bag. tying a knot and turning the excess amount
of bag back over the knot and taping the excess bag below
the knot. Bulk samples should be placed in glass or metal
containers before being sealed in plastic bags. The seal
is then placed just below the knot in such a manner that
it cannot be slipped over. It is important that the sample's
label may be read without opening the sealed unit. If more
than one glass unit is to be sealed in the same bag. it will
be necessary to adequately wrap with packing material all
but one unit in order to prevent breakage. If samples are
'wrapped before sealing in such a manner as to hide the
label. it will be necessary to identify the samples as
instructed in Section l2Gl for bulk samples.
Preparing Seal - EPA Form 7500-2
b.
Pesticide samples will be sealed with EPA Form 7500-2.
This seal will be co~pleted as shown below:
I
iii
...
I
:.'"
a: a:
0-
",N
,
:g
......
~ij;\
L~.( ~~
UNITED HATES
ENVIRONMENTAL PROTECTION AGENCY'
, OFFICIAL SAMPLE SEAL
,"" e4:... e /." M rJ
(1) Insert sample number
(2) Insert date sealed. Use figures. month. day.
year.
(3) Print location of collector IS station.
(4) Signature of person sealing sample.
.
(5) Print name (same as signature) and title of
sealer.
(6) When seal is broken for any purpose. initial here
and enter the date broken. Submit broken seal
with sample records.
jUne 1976
TN 76-1
24
Pesticides Inspection Manual
-------
APPENDIX C
LABORATORY VERIFICATION GUIDELINES
-------
C-l
LABORATORY VERIFICATION GUIDELINES
CHEMICAL DEFICIENCY
The following criteria should be used by the initial analyst to
determine whether to follow up with confirmation analysis after the
first result is obtained, and to determine if a check analysis is re-
quired by a second analyst.
Active Ingredient Label Claim
Minimum Content
Less than 0.51%
0.51 - 1.00%
1.01 - 5.00%
5.01 - 9.99%
10.00 - 50.00%
50.01 - 100%
80% of label claim
85%
90%
92%
94%
96%
A sample result outside these guidelines is not decisive if it
appears that there may have been uncertainties either in the sampling
or analysis of any material. In such cases, the supervisor will decide
whether or not a sample will pass. The allowable deviation below the
label claim for several special cases is given below:
1.
Fertilizer/pesticide mixtures, pressed blocks and non-uniform
baits.
Active Ingredient Content Claimed
Minimum Content
Les s than 1. 26%
1. 26 - 5. 00%
over 5.00%
67% of label claim
80%
85%
-------
C-2
2.
Rotenone, pyrethrin and other natural product formulations.
D
Active Ingredient Content Claimed
Minimum Content
Less than 0.51%
0.51 - 1.25%
over 1. 25%
70% of label claim
80% of label claim
85% of label claim
OVERFORMULATION
The overformulation limit depends on the original label claim,
as follows:
Active Ingredient Content Claimed
Maximum Content
Less than 0.51%
0.51 - 5.00%
5.01 - 10.00%
10.01 - 50.00%
50.01 - 100%
150% of
140% of
130% of
125% of
115% of
label
label
label
label
label
claim
claim
claim
claim
claim
Any overformulation should be verified if any of the following
situations are determined to apply:
a.
An illegal residue would result if used according to direc-
tions.
b.
An additional hazard to the applicator or user would result
because of increased toxicity.
c.
If the product contains label claims 40% sodium fluoride,
Z% sodium arsenite or 1.5% arsenic trioxide, and is in-
tended for household use, then the active ingredient con-
tent should not exceed the label claim by more than 10%
relative.
d.
Overformu1ationwould result in damage to non-target or-
ganisms or the environment (for instance, lawn products
overformulated with herbicides that may damage lawn grass).
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C-3
(NOTE)
Some products are intentionally overformulated at the time of
production because of restrictive shelf-life. This is considered to
be a permissible manufacturing process within certain limits.
Sodium
hypochlorite solutions. DDVP sugarbaits and zinc phosphide prepara-
tions are some typical formulations of this type. If there is any
doubt as to what action to take or not to take in such a situation.
guidance should be obtained from the Region EPA Office or the National
Enforcement Investigations Center Laboratory.
CROSS-CONTAMINATION
The following paragraph is extracted from Appendix F. Contaminant
Screening Guidelines. prepared by PTSED.
liThe presence of any pesticide other than what is declared on
the label and present in quantities equal to or greater than
.05%; however. highly toxic material* (e.g. endrin or sulfotepp)
if present in an amount equal to or greater than .Or%. and unde-
clared herbicides which may cause plant damage at a level greater
than .00r% would be considered contaminants. II
These guidelines should be followed in deciding whether or not
to confirm and check any suspect contaminants.
All cross-contaminants that have been cancelled or suspended
should be reported. such as DOT. aldin. dieldrin. heptachlor and chlor-
dane. 2.4.5-T or silvex. if present at greater than 0.0r%.
*
Highly toxic materials are those materials classified as Toxicity
Category I by the proposed Section 3 guidelines.
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APPENDIX D
REPORT OF ANALYSIS
-------
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ENVI'10NMENTAL PROTECTION AGENCY
I. S.\ ~., p:..... r "J,J.
152088
2. OA' r COLLEC TED
8-15-78
3. REG I 0 ~J
f:ASHlr~G r .'~I. rJ.C. .~'.,. .
4
4. EPA REG. NO.
777 -888
REPORT OF ANALYSIS
5. ESTABLISHMENT NO.
-
6. DESCRIPTION OF SAMPLE
1-1 Gallon metal can; colorless liquid
-.... -----..
7. NAME AND ADDRESS OF ESTABLISHMENT WHE"1E SAMPLE WAS (:.>LLECTED(f/1c1/1(I~ ZIT' coue)
8. PRODUCT NAME
I
-,
Perf Turf
S. Smith, Manager
Magic Pesticides Inc.
88 Bugsa Way
St. Louis, MO
32210
9. LOT OR CODE NUMBER(S)
.
L
.J
B2435-9
~ME AND ADDRESS OF PRODUCER (If dif/erent from 7 above)
-
11. RESULTS OF ANALYSIS
Sample was analyzed and found to be chemically satisfactory.
Analyst:
pf
Delbert Portnoy
9-1-78
Claim
Found
Cadmium (AA; EPA-l)
Screened (TLC; Cl & p):
12.3%
12.6%
Satisfactory
12. LABORATORY COMMENTS
No EPA Est. No. on label or elsewhere on container.
sG
SG
13. SIGNATURE OF LAB Sl{PERVISOR
~~ C~ ~'\
EPA Form 3540-5 Rev. 5-76) '-:J
Sylvia Ginsburg
14. LABORATORY
Bay' St. Louis
15. 0 ATE
9-3-78
SAMPLE RECORD COPY
PREVIOUS EDITIONS ARE OBSOLETE.
-------
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1. SAMPL~ tJ:).
144999
L. DATE COLLECTED
10-10-77
UNITED STATES
::NVIRONMENTAL PROTECTION AGENCY
V:ASHlf4G'r')N, C'.C. ;:'":460
3. REGION
5
4. EI'A REC.. NO.
l3566-78-AA
REPORT OF ANALYSIS
5. ESTABLISHMENT NO.
l3566-0H-l
6. DESCRIPTION OF SAMPLE
1-1 pint bottle of subsample; clear liquid
.. - ----..--
7. NAME AND ADDRESS OF ESTABLISHMENT WHERE SAMPLE WAS .- )LLE::T~D(/IIc1l1de ZIP code)
8. PRODUCT NAME
I
Bill Lipservice, Manager
Babe Ruthless & Co.
800 Seymore Street
Kalmazoo, MI 47880
-,
Fungaway
9. LOT OR CODE NUMBER(S)
.
-
L
.J
.
10. NAME AND ADDRESS OF PRODUCER (If dillerent (rom 7 above)
Armstrong & Doolittle, Cleveland, OH
11. RESULTS OF ANALYSIS
Passed
Analyst:
r;;
Gerald Booth
10-19-77
Claim
Found
2,2-Methylenebis (4-chlorophenol)
(IR; NEIC-563-l)
1.45%
1.2%
Screening (TLC; Cl & P):
Satisfactory
12. LABORATORY COMMENTS
Considered chemically satisfactory for this type of sample. DFJ1'~
13. SIGNATURE OF LI'g SUPERVISOR
\
~ ..>'-..,.,.......;...~ -'} J ,.tv--> -...
E PA Form 3540.5 (Rev. 5.761
Dennis F. Johnson
14. LABORATORY
New York
15. DATE
10-20-77
SAMPLE RECORD COpy
PREVIOUS ~DITtONS ARE OBSOLETE.
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I. ;AMPL' 'JO.
131311
2. D.,TO: COLLECTED
10-27-76
1/" to. S HI'; '"; ~ 'J: ~ I. r.. C":. ;:: 4 -;'"
3. REGION
8
.t. E '" A REG. NO.
7890-33-AA
,
REPORT OF ANAL YS.IS
S. ESTARLI::;HMENT NO.
-
6. DE,SCRIPTION OF SAMPLE
1 - 1 Gallon plastic jug; blue liquid
~- ---
7. N/\ME AND ADDRESS OF ESTABLISHMENT WHERE SAMPLE WAS ':OLLECTED(lllcl",lc 7.lP cod,')
8. PRODUCT NAME
r
Archimedes O'Toole, Vice-President
Alchemist Corp. of America
222 Turngold Way
Boulder, CO 81334
-,
Germigone
9. LOT OR CODE NUMBER(S)
.
L
.J
L61067
10. NAME AND ADDRESS OF PRODUCER (H diffcrenl (rom 7 above)
-
11. ~:ESULTSOF ANALYSIS
Method
Titration (AOAC 6.377)
Ingredient
n-Alkyl(50%C14' 40%C12, 10%C16)
dimethyl benzyl ammonium
chloride
Found
3.1%
Analyst:
~f,!?
Edwa rd R. Green
11-5-76
Net Contents (Est.)
n-Alkyl(*) dimethyl benzyl ammonium
chloride (Titr'n; AOAC 6.377)
Claim Found
1 Gal. 1 Gal.
7% 3.06%
3.08%
3.1 % Avg.
* 50%C14' 40%C12' 10%C16
12. l.ABORATORY COMMENTS
Product is 56% deficient in n-alkyl (50%C14' 40%C12' 10%C16)
dimethyl benzyl ammonium chloride content, based on total chloride. DFH~'
13. SICNATURE OF LAB SUPERV,IWR I ~~
D~ t. \~
Daniel F. Hall
14. LABORATORY
Denver
IS. DATE
11-17-76
SAMPLE RECORD COpy
E PA form 3540-5 (Rev. 5.76)
PREVIOUS EDITIONS 4RE OBSOLETE.
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ENVIRONMENTAL PROTECTION AGENCY
'/:ASHrrJST'J~J, D.C. ;H'4"=C
I. S<\MPL<:: N:=;. ::. DATE COLLECTED
131311 (Continuej)
3. REGION
4. EPA REG. NO.
REPORT OF ANALYSIS
5. ESTABLISHMENT NO.
6. DESCRIPTION OF SAMPLE
7. NAME AND ADDRESS OF ESTABLISHMENT WHERE SAMPLE WAS C.)LLECTEDllllcillrI~ ZIP ,',"/e)
B. PRODUCT NAME
r
-,
9. LOT OR CODE NUMoaER(S)
L
J
10. NAME AND ADDRESS OF PRODUCER III rIilferenl [rom 7 abo,'e)
11. RESULTS OF ANALYSIS
Check Analysis:
n-Alky1 (50%C14' 40%C1Z' 10%C16) dimethyl benzyl
ammonium chloride (Titration; AOAC 6.377): 3.07%,3.09%
Avg.: 3.1%
Jr
Arthur Brown
11-16-76
12. LABORATORY COMMENTS
13. SIGNATURE OF LAB SUPERVISOR
,>,~.;jJ, F. li-~
Daniel F. Hall
14. LABORATORY
Denver
1 5. 0 ATE
11-17-76
SAMPLE RECORD COpy
EPA Form 3540-5 (Rev, 5-76)
PREVIOUS EDITIONS ARE OBSOLETE.
-------
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113172
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3. F!E~j:ON
10
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2, DA 0": ':OLLECTl'D
4-29-75
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r; 'JVIRONMENTAL PPOTEC 'IOIJ AGEIJCY
<'1. EPA. REG. ~JO,
1683- 111-AA
REPORT OF ANALYSIS
5, ESTABLlSI'MF.IJT NO.
1683-0R-2
6. DE~;CRIPTION OtO SAMPLE
1 - 1/2 Pint bottle of subsamp1e; amber liquid
7. NAME AND ADDRESS OF ESTABLISHMENT WHERE SAMPLE WAS r.aLLECTED(lnclllde ZIP ,"nde)
B. PRODUCT NAME
I
Idaho Tree Service
56 Ballantine Road
Boise, 10 88333
'l
Power lindane Spray
9. LOT OR CODE NUMBER(SI
.
-
L
J
10. Nil ME AND ADDRESS OF PRODUCER (II dilIerentIrom? above)
Power Chemical CO., Portland, OR
11. RI~SULTS OF ANALYSIS
Method of Analysis
GlC
GlC
Ingredient Found
lindane 42.1%
DOT 0.1%
Analyst:
tL-S
Haze 1 Smith
5-14-75
Claim
Found
lindane (GlC; 10% OV-1 @ 190°)
DOT (GlC; 10% OV-1 @ 2200)
40%
No Claim
42.1%
0.11%
0.12%
0.1%
0.1%
detected.
Avg.
Screening (TlC-Cl; AOAC 6.026): DOT detected - Ca.
(TlC-P): No. organophosphate contamination
Note: Presence of DOT confirmed on additional GlC column (3% XE-pO
@ 1800) and one additional TlC system (CHC13 on A1203) HS ~
12. LABORATOHY COMMENTS
Product contains 0.1% DOT not declared on the label. Confirmation
is by three GlC systems and two TLC systems. DFHyl-)\.
13. SIGNATURE OF LAB SUPERVISOR
::)~~-.t ').h-d.~
EPA Form 3540-5 (Rev. 5-76)
Darlene F. Horton
14. LABORATORY
New York
I 5. 0 ATE
5-20-75
Si-\MFlE RECORD COpy
PREVIOUS EC,ITIONS ARE OBSOLETE.
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APPENDIX E
CONTAMINANT SCREENING GUIDELINES
-------
CONTAMINANT SCREENING GUIDELINES
Prepared by:
Scientific Support Branch
Pesticides and Toxic Substances
Enforcement Division
February 1977
-------
:.
"
Contaminant Screening Guidel ines -
E-2
Purpose
Pursuant to Section 23(a) of the Federal Insecticide, Fungicide,
and Rodenticide Act, as amended 1n 1972 and 1975, the Assistant Admin-
istrator for Enforcement gave notice, publishe~ in 41 FR 32778 (Thursday
August 5, 1976), that the Environment,~l P,rotection Agency '"''auld be
implementing a pesticides enforcement'grant-in-aid program, for fiscal
year 1977, to certaip1State lead agencies whose responsibility is to
enforce State pesticide laws. Included in the grant contract 1s a
clause which requires that State participants in the pesticides enforce-
ment program screen pesticide formulations for contaminants. It is
therefore the intent of this document: ' .
, Q!11ectives
, 1)
1)
To provide the participating States the necessary
. guidelines to screen for contam; nants.
To provide guidelines which non-participating States
may adopt in order to enhance their pesticides enforce-
ment p~09ram. '
2)
2)
To ensure that contaminated products having the potential
for hazardous contact with man, domestic animals, and the
environment are routinely screened to help eliminate incidents.
~1ch may jeopardize public safety; ,
To enhance the pesticides enforcement program by detecting
contaminants that would otherwis~ go unnoticed;
3)
To provide guidelines which are designed to alert
responsible State lab supervisors to potential problems and to
allow them to proceed on each contamination case based on
their judgment as to residues, exposure and handling hazards.
Background
A basic concern of FIFRA, as amended, is to ensure that pesticides
registered for use within the United States perform their functions
without causing undue hazards to wan and the environment. Numerous
provisions within FIFRA and its regulations have been created to allow
for this compatibility. One such provision is paragraph 162.10(g)(5) of
FIFRA Section 3 Regulations which requires that pesticides contain as
precise as possible those percentages of ingredients that are repre-
sented on the product label. If the product does not meet th~se speci-
fications, it is said to be adulterated, and its resultant quality may
be such as to render it ineffective, unsafe, and I;InacLeptabl eo'
-------
-2-
E-3
EPA labs routinely screen certain pesticides for contamination
in an effort to minimize any deleterious impact on man or the environ-
ment. One EPA lab has reported that 5X of all pesticide samples analyzed
at any given time are contaminated. If these pesticides go unscreened.
contaminants go undetected and the concomitant enforcement actions
(i.e.. Notice of Warning. Civil Complaint. Criminal Prosecution. Stop'
Sale. and/or Recall) are not taken. The dividend from. screening for
contaminants out~~igh the minimal amounts of time. cost. and equipment
expended and the results are vital to a good enforcement program.
Discussion and Definition of Contamination
For the purpose of these guidelines. contamination does not include
impurities that arise from reacticns that occur during the manufacture
of a product. Sources of contamination in pesticides may originate from
such activities as failure to clean equipment between production runs
and the reuse of inadequately cleaned or uncleaned pesticide containers.
Based on practical reasons i.e.. time. cost. and resources. the
following definiticn has been used for establishing that point at which
the analytical chemist sho~ld run further analysis to identify and
quantify the contaminant:
The presence of any pesticide other than what is declared
on the label and present in quantities equal to or greater
than .05%; however. highly toxic material* (e.g. endrin or
su1fotepp) if present in an amount equal to or greater than
.01%. and undeclared herbicides which ~ay cause plant damage
at a level greater than .001% would be considered contaminants.
. Requirements
1)
Products to screen.
a.
Those pesticides intended for use on agricultural'
commodities (before or after shipment to the public
market place) which will be used for human or animal
consuwption.
b. Those pesticides used for home gardening.
c. Those pesticides used to control pests on pets.
*
Highly toxic materials are those materials classified as Toxicity
Category I by the proposed Section 3 guidelines.
-------
.
E-4
d.
Those pesticides use~ in or around the home. . (Not
to include disinfectants such as quaternary compounds,
bleaches and swimming pool treatments). "
e.
",
Those pesticide5 used io processing plants and'
institutions. " '.
f. . Those pesticides used on humans.
Contaminant detection.
"2)"
a.
The presence of a contaminant should be determined"
based on the definitions given in these guidelines.
If the contaminant is significant, its identity and
percentage should be determined based on standard
analytical methods, i.e., gas'chrom3.tography, rrass
spectrometry, etc.
" "
. b.
.3}
Thin layer Chromatography (TlC) methods to screen for the .
presence of contaminants. (TLC will not detect all contaminants
. that may be rresent bu tis adequa te for rout; ne screen i ng . )
a.
. TLC for organophosphorus pesticides - AOAC 29.022. "
TLC for chlor~nated hydrocarbon pesticides - AOAC 6.030.
b.
c.
TLC section'wi"thin U.S. EPA l'.anual of Chemical r'~ethods
" "for Pesticides and Devices.
d.
Other methods approved by EPA.
If the method of analysis used in determining the product formu-
"'1ation reveals contaminants (e.g. gas chrom3.tography), then the analyst
:need not use any of the TLC methods. . . "
4)
Materials and Equipment to use in determining the presence
. of a contami nant.
B.. " Technical grade stc.ndards and not analyti:nl gr.3.de
. standards need to be used for comparison purposes.
. b.
Pre-coated plates are generally available from most
chemical supply houses and rr~y be used ir.stead of
homemade plates.
For chlorinated pesticides: refer to AOAC-6.026-6.029.
c.
-------
E-S
d.
For organophosphorus pesticides: refer to AOAC-6.026-
6.29.
Refer to TLC section \'lithin U.S. EPA .Hanual of Chemical.
Methods for Pesticides and Devices.. .
Report of Analysis. .
e.
5)
. The results of the c~ntaminant screening and. the identity and
percentage of each contaminant, if determined, should be reported on the
standard EPA. Sample Summary Analytical Report (EPA Fonn 8500-4).
. Note: It is generally not necessary to screen for inorganic contaminants.
However, if the analyst suspects inorganic contamination, then atomic
abS01"ption spectroscopy shou1d be used to search fer the !i.ost probable
contaminants, i.e., arsenic, lead, and cadmium. .
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APPENDIX F
INSTRUMENT AUDITS
-------
F -1
INSTRUMENT AUDITS
In order to ascertain the operational status of the gas chroma-
tographic and liquid chromatographic systems (instruments, columns,
and detectors) used for analytical quanti tat ion , the following audits
should be performed once/week or whenever instrument malfunction is
suspected.
Suggested Gas and Liquid Chromatographic parameters are given in
Tables 1 and 2. Specific parameters will have to be established
according to available instrumentation.
Once equilibrated, 2 ~l of the appropriate test standards (e.g.
Hall Cell, FID, FPD-NPD) are injected. The components of the
test standards are listed in Table 3.
All audit results should be recorded and filed in the instrument
log book and compared to previous test standard injections. The
retention times and sensitivities should be within 5% of the
original recorded value. If the results fall below these
limits, several more injections should be made by the analyst
until the values fall within the limits. Quantitative analyses
should not be performed on the instrument if it fails to meet
the audit limits. If, after three injections, the values still
do not fall within the specified limits, the analyst should as-
certain the problem and/or consult with the supervisor prior to
continuing on with analysis.
-------
Table 1
GAS CHROMATOGRAPHIC PARAMETERS
Col. Attn. Temp. Flow
Detec- Column Col. Flow Temp Input Recor- Inj. Detec- Air H2 Inj. Vol. Comments
tor No. N2 °C der °C tor
FID-1 3% Carbo- 4 4x40 200°C 10 28 225 300 0.8 30 2 ul
wax 20M
FID-2 3% OV-l 2 3x40 20o/min 10 28 225 300 0.8 30 2 ul
150(2a)~210(2a)
FID-A 3% XE-60 8 20x69 30o/min 100 23 250 250 Pre-set 2 ul
150(2a)~200(4a)
FID-B 3% OV-1 7 30x69 300min 100 22 250 250 Pre-set 2 ul Sp 1 it 1: 1
150(2a)~210(2a)
NDP 3% OV-1 . 7 15x69 190 10 27 250 250 Pre-set 2 ul Sp 1 it 1: 1
FPD 3% OV-1 2 6x40 190 104 (1)256 225 200 125 70 2 ul Bucking=6
Ch. =Ph. (2) 64
Ch.=S.
Hall 3% OV-1 1 5x40 200 10 28 225 860 50 2 ul
Cell
FIDs 1 & 2 on MT-222
FIDs A & B on PE Sigma 1
a Hold Time (min.)
"
I
N
-------
"-
II
F-3
Table 2
LIQUID CHROMATOGRAPHIC PARAMETERS
HPLC Conditions
Column: ~ Bondapak C1S (Waters)
Col. Temp. = 28°C
Flow: 2.0 ml/min
Reservoirs: A = H20 B = CHaCN
AUFS = 0.2 Attn. = 2
A = 254 nm
Gradient Profile
Time Code Value
.0 Flow 2.0
.0 % B 60
2.5 % B 60
3.0 % B 100
7.0 % B 100
-------
F-4
Table 3
TEST STANDARDS
Component Approx. Cone.
(Accurately Weighed)
FID Test Std. Dimethyl Phthalate 1 mg/ml
Diethyl Phthalate 1 mg/ml
Dibutyl Phthalate 1 mg/ml
Hall Cell Gamma-SHC 10 ug/ml
Test Std. Aldrin 10 ug/ml
FPD-NPD Diazinon 10 ug/ml
Test Std. Parathion 10 ug/ml
Methyl Parathion 10 ug/m 1
HPLC Dimethyl Phthalate 1 mg/ml
Test Std. Diethyl Phthalate 1 mg/ml
Dibutyl Phthalate 1 mg/ml
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