Principles, Statistics, and Applications

295 Pages·1986·4.68 MB·English

by  Gunter Zweig and Joseph Sherma (Eds.)

Analytical Methods for
PESTICIDES AND
PLANT GROWTH REGULATORS
Edited by
GUNTER ZWEIG and JOSEPH SHERMA
Volume XV
PRINCIPLES, STATISTICS,
AND APPLICATIONS
Volume edited by
GUNTER ZWEIG and JOSEPH SHERMA
Zweig Associates Department of Chemistry
Arlington, Virginia Lafayette College
East on, Pennsylvania
1986
®
ACADEMIC PRESS, INC.
Harcourt Brace Jovanovich, Publishers
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COPYRIGHT © 1986 BY ACADEMIC PRESS, INC.
ALL RIGHTS RESERVED.
NO PART OF THIS PUBLICATION MAY BE REPRODUCED OR
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ACADEMIC PRESS, INC.
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United Kingdom Edition published by
ACADEMIC PRESS INC. (LONDON) LTD.
24-28 Oval Road, London NW1 7DX
Library of Congress Cataloging in Publication Data
(Revised for vols. 14 & 15)
Zweig, Gunter.
Analytical methods for pesticides, plant growth
regulators, and food additives.
Vols. 6- have title: Analytical methods for
pesticides and plant growth regulators.
Vols. 6- edited by G. Zweig and J. Sherma.
Includes bibliographies.
1. Pesticides—Analysis—Collected works. 2. Plant
regulators—Analysis—Collected works. 3. Food
additives—Analysis—Collected works. 4. Feed
additives-Analysis—Collected works. 5. Chemistry,
Analytic-Collected works. I. Sherma, Joseph.
II. Title. III. Title: Analytical methods for
pesticides and plant growth regulators.
SB960.Z9 632'.95 63-16560
ISBN 0-12-784315-9 (v. 15)
PRINTED IN THE UNITED STATES OF AMERICA
86 87 88 89 9 8 7 6 5 4 3 2 1
Preface
Almost a quarter of a century has elapsed between the time the first
volume of this series was published and the appearance of the present
Volumes XIV and XV Volume I of the original "Analytical Methods for
Pesticides, Plant Growth Regulators and Food Additives," which was
shortened to its present title beginning with Volume VI, was intended to
introduce the reader to the principles and general and specific methods of
pesticide analysis. With subsequent volumes, we attempted to stay abreast
of new and improved analytical methods and techniques.
We perceived the need for a comprehensive volume to cover newer
concepts, principles, and applied analytical methods in order to meet the
requirements of the latter part of the 1980s. Academic Press has supported
our efforts throughout this period and encouraged us to undertake this new
task. In fact, one of us (GZ) has had a long and fruitful relationship with
Academic Press, going back to 1951 when it published 'Taper Chro-
matography" by Block, Le Strange, and Zweig as one of the first books on
this subject.
Volume XV covers general principles of pesticide analysis and
application of the techniques that are discussed in Volume XIV In the present
volume, the reader will be introduced to methods dealing with the analysis
of pesticide formulations and residues in biological systems, food, and the
environment.
Chapter 1 is a detailed treatment of government regulations for the safe
use of pesticides and presents a rationale for the need for pesticide analyses.
An updated chapter (Chapter 2) on the statistics of sampling and analyses
includes the application of computers. Most pesticide analysts will un-
doubtedly agree that cleanup is more than half the battle in obtaining accurate
and precise residue data. Cleanup techniques are covered in Chapter 3.
International acceptance and interlaboratory comparisons of pesticide
residue data are becoming increasingly important and are discussed in
Chapter 4.
Part II of the book is a discussion, review, and description of analytical
methods to meet the unique requirements imposed by analyses of active
ingredients in formulations (finished products), pesticide residues in foods
and the environment, and pesticide metabolites in plants and animal tissues
(metabolism studies).
We are fortunate to produce these two volumes with the collaboration
of pesticide experts who are professionally active in their specialties and work
in governmental, academic, and industrial laboratories.
As in previous volumes, we are again inviting our readers to submit to
us their comments and possible errata, which inevitably seem to arise in spite
vu
viii PREFACE
of careful proofing by the authors, editors, and production staff of the
publisher. We also want to invite our readers to suggest topics that should be
covered in subsequent volumes of this series, and most desirably, to
encourage our correspondents to offer their services or nominate one of their
colleagues to join our distinguished group of contributors.
Gunter Zweig
Joseph Sherma
1
U.S. Government Regulation of
Pesticides
DANA PILITT*
U.S. Environmental Protection Agency
Office of Pesticide Programs
Registration Division
Washington, D.C. 20460
I. INTRODUCTION
The increasing dependency of American agriculture upon govern-
mentally regulated pesticides that has occurred since the development of
synthetic organic pesticides presents expanding opportunities and chal-
lenges to the analytical chemist. The chemistry of pesticides has evolved
from a few simple inorganics such as arsenic, lead, fluoride, and some
naturally occuring materials such as pyrethrins and rotenone to the present
vast array of organics whose actions cover the range from broad-spectrum
to highly specific pest control. Concurrently with expansion of new chem-
icals into the environment has arisen increasing public and governmental
interest in the regulation of the pesticide industry. Concerns about pesticide
levels in our food, the leaching of pesticides into our water supply, and
the impact of applied pesticides on wildlife has focused attention on the
much increased role of analytical chemistry in the protection of both public
health and the environment. The formulation chemist's identification and
quantification of each component of the pesticide formulation and deter-
mination ofthat product's chemical and physical properties, plus the an-
alytical chemist's determination of the nature and amount of the residues
that result from applying that pesticide either to food or feed crops, live-
stock animals or farm buildings, or to food handling and processing fa-
cilities, as well as his identification of the metabolites and degradation
products that remain in the environment following that pesticide's use,
serve as the bases for all the toxocological, wildlife safety, and environ-
* This chapter was written by Dana Pilitt in his private capacity. No official support
or endorsement by the Environmental Protection Agency or any other agency of the Federal
Government is intended or should be inferred.
3
ANALYTICAL METHODS FOR PESTICIDES Copyright <r) 1986 by Academic Press, Inc.
AND PLANT GROWTH REGULATORS. VOL. XV All rights of reproduction in any form reserved.
4 DANA PILITT
mental fate studies that support the registration governing the acceptable
uses of each pesticide.
II. LAWS REGULATING PESTICIDES
The three main reasons for any government to regulate the safe use
of pesticides are (1) to protect the general public from exposure to harmful
levels of pesticide residues by ingestion, inhalation, or any other contact;
(2) to protect pesticide applicators and farmworkers from harmful exposure
to pesticides; and (3) to protect the environment from unreasonable adverse
effects due to pesticides (Zweig, 1984). The U.S. Environmental Protection
Agency (EPA) regulates the sale, distribution, and use of pesticides under
the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as
amended. This current pesticide law has evolved through a series of laws
and amendments that reflect the major concerns at the time of their en-
actment. The original Insecticide Act of 1910 regulated the old inorganic
pesticides and placed its emphasis on efficacy concerns and ensuring that
the product met its declared percentages. This was replaced in 1947 by
the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), which
reflected concern over the need to regulate the newly available synthesized
organic compounds. FIFRA was amended in 1959 to include not only
insecticides, fungicides, and rodenticides but also herbicides and plant
growth regulators plus other miscellaneous compounds, all of which would
be classified generically as pesticides (Leng, 1981). These pesticide laws
had been administered by the U.S. Department of Agriculture (USDA).
Public and governmental concern over protecting the environment resulted
in the establishment of the U.S. Environmental Protection Agency in 1970.
Regulation of pesticides was transferred to this new agency from the
USDA. The Federal Environmental Pesticide Control Act of 1972 (orig-
inally known as FEPCA) has been amended several times since then, the
latest being 1978, and today the pesticide law is known as "FIFRA, as
amended."
Supporting the use of pesticides on food crops and animals are tol-
erances and exemptions from tolerances based on residue data required
under the Federal Food, Drug and Cosmetic Act (FFDCA). A tolerance
can be defined as the maximum legal pesticide residue permitted to remain
in or on food. The original FFDCA, enacted in 1938, prohibited the addition
of any quantity of a poisonous or deleterious substance to food unless it
was required or could not be avoided in the production of the food. Under
that law it was not necessary for the pesticide producers to demonstrate
the safety of the food additive, but rather the government had to show
1. GOVERNMENT REGULATION OF PESTICIDES 5
that the substance was deleterious. FFDCA has been amended over the
years to shift the burden of proving safety to the pesticide producers. The
1954 amendment, called the Miller Bill or Public Law 518, dealt with reg-
ulating the safe use of pesticides relative to the production of raw agri-
cultural crops by establishing the need for tolerances under Section 408
of that Bill. The Food Additives Amendment, including the Delaney
Amendment of 1958, extended Federal control over food additives and
those chemicals that have been shown to cause cancer in humans or an-
imals. The types of compounds and additives covered under FFDCA were
expanded further by the 1959 Colley Amendment to include plant growth
regulators, nematicides, and herbicides, and by the 1960 Color Additives
Amendment (Zweig, 1963). The authority to set tolerances was originally
given to the Secretary of Health, Education and Welfare, but it was trans-
ferred to the Administrator of the EPA with the founding of the agency
in 1970.
While most tolerances established under FFDCA are usually to cover
pesticide residues present as a direct result of the intentional use of a
pesticide in this country in accordance with its registration under FIFRA,
tolerances can also be established to cover those residues that may be
present as a result of pesticide application made in a foreign country prior
to import of the food commodity. Tolerance levels (usually parts per mil-
lion, ppm) are established through the EPA, but actual monitoring of the
food supply is accomplished by the Food and Drug Administration (FDA)
and the USDA. The USDA's Food Safety and Inspection Service (FSIS)
enforces the tolerances for residues in meat and poultry under the Federal
Meat Inspection Act and the Poultry Products Inspection Act. Tolerances
for residues in eggs and egg products are enforced by the USDA's Ag-
ricultural Marketing Service (AMS) at establishments having official USDA
egg inspection service and by FDA under the Egg Products Inspection
Act at the remaining locations. All other pesticide tolerances are enforced
by FDA. FDA also sets "action levels" (enforceable residue limits) for
pesticide residues detected in raw agricultural commodities and fish that
are not covered by formal tolerances for cases resulting from inadvertent
exposure (Wolff, 1976). EPA has recently begun to revoke tolerances and
set "action levels" for pesticides whose registered uses on food crops
have been cancelled but whose persistence in the environment still results
in residues present in food.
The users of pesticide products, whether homeowners or large-scale
commercial or agricultural applicators, expect the pesticide product they
are using to actually contain the ingredients in the declared concentration
and assume that if they follow the label directions and precautions, the
application will be made at a correct rate to achieve the claimed control
6 DANA PILITT
but will not result in direct adverse effects to themselves or the plants
and animals they are trying to protect, or result in residues remaining on
crops at harvest that would render them unfit for consumption or sale.
While these are reasonable assumptions, few users fully appreciate the
requirements that must be met before that pesticide product can be legally
sold in this country. Even those deeply involved in certain aspects of the
development of the required supporting data, such as the formulation or
analytical chemist, may not have an overview of the entire registration
process (Fig. 1) or know the place that the individual's input has in the
overall decision-making process that is involed in an initial or amended
Federal pesticide registration.
A. Federal Insecticide, Fungicide, and
Rodenticide Act (FIFRA), as Amended
Registration of pesticide use in the United States is accomplished
under the various sections of FIFRA, as amended. Section 3 pertains to
the usual registration procedures that apply to the majority of pesticides
and uses in this country. If the pesticide or its metabolites can be rea-
sonably expected to leave residues in or on food or feed, then the reg-
istration must be supported by either a tolerance or an exemption from
tolerance under FFDCA. Experimental use of a pesticide, to gather data
necessary to support the Section 3 registration of a new use for an already
registered chemical or of a new chemical that does not have a Federal
pesticide registration, is accomplished under Section 5 of FIFRA. If the
use of the experimental pesticide will involve residues in or on food, and
the crop will not be destroyed after the test or be fed solely to test animals
to obtain other necessary data, then it must be supported by a temporary
tolerance or exemption from tolerance. Federal or state agencies may apply
under Section 18 of FIFRA for a crisis exemption to use a pesticide in a
manner that does not have a federal registration, but use can be only for
a limited period of time and against a specific pest to meet emergency
control needs. Individual states can provide for additional uses that do
not appear on the federally registered pesticide label to meet particular
pest-control needs in their state under the provisions of Section 24 of
FIFRA, as long as a tolerance is already in place to cover resulting res-
idues, if the use involves a food crop.
Each proposed pesticide product to be registered under Section 3 of
FIFRA begins with the product registration kit, currently available from
the Registration Support and Emergency Response Branch, Office of Pes-
ticide Programs, Registration Division of the U.S. EPA.* This kit contains
* 401 M Street, S.W., Washington, D.C. 20460.
> REGULATORY DECISION IF ACCEPTABLE:- Establish Tolerances - Prepare Federal Register Notices - Approve Label IF NOT ACCEPTABLE Registrant May: - Replace Data and/or - Revise Label and/or - Revise Uses and/or - Clarify Uses
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EVIEW OF DATA et Guidelines Support Label?) duct Chemistry idue Chemistry osure Assessment icology logical Effects nds to Agency)
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(M&PrReExToEc sp
SUBMISSION —> PROCESSING ssign File Symbol (Product) ssign Accession # (Data) heck for Completeness oute Data for Review A A (Company Re of the registration process.
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NEW CHEMICAL APPLICATION: Supporting Data - Product Chemis- Toxicology - Environmental - Ecological Eff(Fish & Wildl Tolerance Petiti- Residue Chemis- Special ToxiciData - Fees OLD CHEMICAL APPLICATION: Supporting Data - Product Chemis- Acute Toxicity Data Compensatio- PR Notice 85-3- 40 CFR §152 Subpart E FIG. 1.
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Pesticide AssessmentGuidelines& Part 158 Guidelines

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8 DANA PILITT
copies of FIFRA, pertinent regulations and notices dealing with pesticide
registration data support requirements, a microfiche listing of those who
have submitted pesticide data to the agency, data compensation and ar-
bitration procedures, and pesticide product labeling requirements, as well
as a variety of forms that must be completed for the registration appli-
cation. In addition to the registration kit, registrants who are considering
making their first application for an Experimental Use Permit or a Section
3 registration that will depend upon their own data will find it most ben-
eficial to obtain copies of the Pesticide Assessment Guidelines that pertain
to their individual data or application needs. These documents are avail-
able, for a charge, from the National Technical Information Service
(NTIS).* Since each federally registered pesticide bears an identifying
number consisting of the company number followed by a sequentially as-
signed specific product number, first-time applicants will find a form in
the registration kit that should be submitted to their local EPA Regional
Office for obtaining a unique pesticide company identifying number and
a pesticide-producing establishment number, which must also appear on
each product label to indicate the point of origin for a given batch. Reg-
istrants seeking to initiate field testing of an experimental pesticide will
find an "Application for Experimental Use Permit," EPA form 8570-17,
plus information on applying for an Experimental Use Permit and its as-
sociated temporary tolerance if a food or feed use is involved. Detailed
information on Experimental Use Permits can be found in Part 172 of
Volume 40 of the Code of Federal Regulations (40 CFR), which is available
from the Superintendent of Documents, U.S. Government Printing Office,
Washington, D.C. 20402, and Subdivision I of the Pesticide Assessment
Guidelines, available from NTIS. Registrants who seek to amend a reg-
istration may find themselves facing data support requirements similar to
those required for a new registration. Whether or not support data will
be required can be determined by checking if the proposed amendment
is included in the listing of amendment types that do not require data,
which appears in 40 CFR, Part 152, Subpart E, Section 152.81(b)(4). The
largest percent of the EPA's registration activities involve so-called ume-
too" applications, either for new products that mimic currently registered
products or for amendments to add sites and pests that are declared on
labels of similar products. There are support data requirements for such
applications.
Each federal pesticide product registration must be supported by data
to show that consistent with its benefits, its use will not significantly in-
crease the risk of unreasonable adverse effects to humans or the envi-
* 5285 Port Royal Road, Springfield, Virginia 22161.