Pesticide profiles : Toxicity, environmental impact and fate - Chapter 1 pot

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Introduction

This book has its genesis in the efforts of a large number of individuals over a
long period of time. It is the outgrowth of an effort started a number of years ago
to provide clearly understandable information about the toxicology and environ-
mental chemistry of pesticides to those who use and may be affected by these
compounds. The people most responsible for these initial activities are Dr. James
Witt and Dr. Frank Dost, both from Oregon State University.
About a decade ago, these pioneers were joined by other scientists at the Uni-
versity of California at Davis, Cornell University, and Michigan State University to
form a consortium known as EXTOXNET. Together this group planned the coordi-
nated production of Pesticide Information Profiles (PIPs) (summarizing environmen-
tal toxicology and chemistry information) and Toxicology Information Briefs (TIBs)
(providing brief overviews of important environmental toxicology and chemistry
concepts). This consortium was able to obtain a small amount of funding that orig-
inated in the U.S. Environmental Protection Agency (Office of Pesticides and Toxic
Substances) and was administered by Extension Service-USDA through the National
Pesticide Applicator Training Program. Combined with large contributions of time
and effort by the participants, these funds were used to produce 100 profiles and
about 15 briefs that were published in 1989.
After a brief hiatus, new funding for this effort was identified in the USDA

National Pesticide Impact Assessment Program and this funding has continued to
the present. Nancy Ragsdale and Dennis Kopp of USDA-NAPIAP have been instru-
mental in supporting this program and facilitating its efforts. With the additional
funding, the original PIPs and TIBs were revised and an additional 85 PIPs and about

5 TIBs were produced. A second collection of materials, called the

Pesticide Information
Notebook,

was published in 1994 with many of the additional PIPs and TIBs included.
Because these materials were produced at four different universities over a long
period of time, and involved a large group of contributors, a number of inconsisten-
cies arose in the information provided and the way this information was described.
This book represents an almost 2-year effort to update and standardize the PIPs and
TIBs and to include additional information so that an even more valuable resource
is the result.
As suggested previously, this book could not have been written without the
essential contributions of faculty, staff, and students at the four universities involved
in EXTOXNET. At the University of California at Davis, the effort is headed by Arthur
Craigmill, with the assistance of Sandy Ogletree and Loreen Kleinschmidt. At Cornell
University, the work is supervised by Don Rutz and William G. Smith, with the
current assistance of Eric Harrington and previous help from Linda A. Seyler. Pre-
vious faculty contributors from Cornell include Kean S. Goh, James W. Gillett, Chris-
topher F. Wilkinson, Barbara Hotchkiss, and Ann T. Lemley. The Oregon State Uni-
versity faculty who have succeeded Jim Witt and Frank Dost are Terry Miller and

© 2000 CRC Press LLC

Jeff Jenkins, and they have been assisted by Pat Thomson. In addition, another faculty

member, Sheldon Wagner, has been a long-term contributor to the effort.
At Michigan State University, the EXTOXNET program is headed by the editor
of this book, Michael Kamrin, and he has been fortunate to have a large number of
talented students contribute their efforts to this project. They include Suanne Miller,
Monica Schmitt, Jon Allan, Susan Pigg, Renee Pionk, and Matthew Moon. However,
the person most responsible for bringing together all the components needed to
produce this book is Bradley Aaron, M.S. In addition, a number of staff at the Institute
for Environmental Toxicology have been instrumental in many tasks required for
the successful completion of this project. They include Mary Robinson, Carole Abel,
Carol Fischer, Darla Conley, Paul Groll, and Richard Davis.
Last, but not least, a large number of scientists in academia and industry volun-
teered their time to review drafts of the PIPs and TIBs, and their comments have
been invaluable in producing an accurate and readable final product. Many of these
scientists are members of the Society for Environmental Toxicology and Chemistry,
which assisted in soliciting a large number of experts as reviewers. Although the
names of the reviewers are not listed here, each of them has the deep gratitude of
the editor and the EXTOXNET members.
In a large project of this kind, it is impossible to identify everyone who has
contributed. The editor hopes that those who have not been mentioned will still take
pride in being associated with this project and in the publication of this volume.

Michael A. Kamrin, Ph.D.

© 2000 CRC Press LLC

The Editor

Michael A. Kamrin, Ph.D., is a Professor in the Institute for
Environmental Toxicology and the Department of Resource
Development at Michigan State University. Dr. Kamrin ob-

tained his training at Cornell University, where he received a
B.A. in Chemistry in 1960, and at Yale University, where he
received an M.S. in Biophysical Chemistry in 1962 and a Ph.D.
degree in Biophysical Chemistry in 1965. He served as an
Assistant Professor at Michigan State University from 1967 to
1972; an Associate Professor from 1972 to 1979; and a Professor
from 1979 to the present. He joined the Institute for Environ-
mental Toxicology in 1982 and the Department of Resource
Development in 1990. Dr. Kamrin was also appointed a Docent at the University of
Turku (Finland) in 1996.
Dr. Kamrin is a member of the American Association for the Advancement of
Science, the Society of Toxicology, the Society of Environmental Toxicology and
Chemistry, the Society for Risk Analysis, the American Chemical Society, and the
honorary society Sigma Xi. He has served as president of the Michigan Chapter of
the Society of Toxicology and the Central Great Lakes Chapter of the Society of
Environmental Toxicology and Chemistry. He received the Public Communications
Award of the Society of Toxicology and the University of Turku (Finland) Memorial
Medal. He has been the recipient of many research and outreach grants from the
U.S. Department of Agriculture, the National Institute of Environmental Health
Sciences, and the U.S. Environmental Protection Agency. Dr. Kamrin is the author
of more than 50 scientific articles and outreach publications on environmental toxi-
cology. He is sole or primary author of two books and co-editor of two other books.
His major interests are risk assessment and risk communication, especially with
respect to environmental contaminants.

© 2000 CRC Press LLC

Contents

Section I: Introduction to pesticide profiles and basic concept papers

1 Introduction and profile description

1.1 Introduction
1.2 Description of profile categories
1.3 Disclaimer

Section II: Pesticide Profiles
2 Pyrethroids and other botanicals

2.1 Class overview and general description
2.2 Individual profiles
2.2.1 Allethrin
2.2.2 Cypermethrin
2.2.3 Esfenvalerate
2.2.4 Flucythrinate
2.2.5 Fluvalinate
2.2.6 Permethrin
2.2.7 Resmethrin
2.2.8 Rotenone
2.2.9 Ryania
References

3 Carbamates

3.1 Class overview and general description
3.2 Individual profiles
3.2.1. Aldicarb
3.2.2 Bendiocarb
3.2.3 Carbaryl
3.2.4 Carbofuran

3.2.5 Chlorprofam
3.2.6 Fenoxycarb
3.2.7 Methomyl
3.2.8 Oxamyl
3.2.9 Propoxur
References

© 2000 CRC Press LLC

4 Thio- and dithiocarbamates

4.1. Class overview and general description
4.2 Individual profiles
4.2.1 Butylate
4.2.2 EPTC
4.2.3 Mancozeb
4.2.4 Maneb
4.2.5 Metiram
4.2.6 Molinate
4.2.7 Thiram
4.2.8 Triallate
4.2.9 Zineb
4.2.10 Ziram
References

5 Organophosphates

5.1 Class overview and general description
5.2 Individual profiles
5.2.1 Azinphos-methyl

5.2.2 Bensulide
5.2.3 Chlorpyrifos
5.2.4 Coumaphos
5.2.5 Diazinon
5.2.6 Dichlorvos (DDVP)
5.2.7 Dimethoate
5.2.8 Disulfoton
5.2.9 Ethion
5.2.10 Fenamiphos
5.2.11 Fenthion
5.2.12 Fonofos
5.2.13 Isofenphos
5.2.14 Malathion
5.2.15 Methidathion
5.2.16 Methyl parathion
5.2.17 Mevinphos
5.2.18 Naled
5.2.19 Phorate
5.2.20 Phosmet
5.2.21 Propetamphos
5.2.22 Temephos
5.2.23 Terbufos
5.2.24 Trichlorfon
References

6 Chlorinated hydrocarbons

6.1 Class overview and general description
6.2 Individual profiles
6.2.1 Chlordane

6.2.2 Chlorobenzilate
6.2.3 Chlorothalonil

© 2000 CRC Press LLC

6.2.4 Dalapon
6.2.5 Dicofol
6.2.6 Dienochlor
6.2.7 Endosulfan
6.2.8 Heptachlor
6.2.9 Hexachlorobenzene
6.2.10 Lindane
6.2.11 Methoxychlor
6.2.12 PCNB (Quintozene)
6.2.13 Pentachlorophenol
References

7 Phenoxy and benzoic acid herbicides

7.1 Class overview and general description
7.2 Individual profiles
7.2.1 2,4-D
7.2.2 2,4-DB
7.2.3 Chloramben
7.2.4 DCPA
7.2.5 Dicamba
7.2.6 Fluazifop-p-butyl
7.2.7 MCPA
7.2.8 Quizalofop-p-ethyl
References

8 Triazines and triazoles

8.1. Class overview and general description
8.2 Individual profiles
8.2.1 Amitrole
8.2.2 Atrazine
8.2.3 Cyanazine
8.2.4 Hexazinone
8.2.5 Metribuzin
8.2.6 Prometryn
8.2.7 Propazine
8.2.8 Simazine
8.2.9 Triadimefon
References

9 Ureas

9.1 Class overview and general description
9.2 Individual profiles
9.2.1 Diflubenzuron
9.2.2 Diuron
9.2.3 Fluometuron
9.2.4 Linuron
9.2.5 Primisulfuron-methyl
9.2.6 Sulfometuron-methyl
9.2.7 Tebuthiuron
References

© 2000 CRC Press LLC

10 Other pesticides

10.1 Chapter overview
10.2 Fungicides
10.2.1 Benomyl
10.2.2 Captan
10.2.3 Carboxin
10.2.4 Copper sulfate
10.2.5 Dinocap
10.2.6 Dodine
10.2.7 Imazalil
10.2.8 Iprodione
10.2.9 Metalaxyl
10.2.10 Thiabendazole
10.2.11 Vinclozolin
10.3 Herbicides
10.3.1 Acifluorfen
10.3.2 Alachlor
10.3.3 Ammonium sulfamate
10.3.4 Bentazon
10.3.5 Bromacil
10.3.6 Bromoxynil
10.3.7 Cacodylic acid
10.3.8 Clomazone
10.3.9 Dinoseb
10.3.10 Diquat dibromide
10.3.11 Glyphosate
10.3.12 Metolachlor
10.3.13 Napropamide

10.3.14 Oryzalin
10.3.15 Oxyfluorfen
10.3.16 Paraquat
10.3.17 Pendimethalin
10.3.18 Picloram
10.3.19 Pronamide
10.3.20 Propanil
10.3.21 Sethoxydim
10.3.22 Terbacil
10.3.23 Triclopyr
10.3.24 Trifluralin
10.4 Insecticides
10.4.1 Abamectin
10.4.2

Bacillus thuringiensis


10.4.3 Hydramethylnon
10.4.4 Methoprene
10.4.5 Sulfuryl fluoride
10.5 Others
10.5.1 4-Aminopyridine
10.5.2 Daminozide
10.5.3 Diphacinone
10.5.4 Ethylene dibromide (dibromoethane)

© 2000 CRC Press LLC

10.5.5 Metaldehyde

10.5.6 Methyl bromide (bromomethane)
10.5.7 Tributyltin (TBT)
10.5.8 Zinc phosphide
References

Section III: Basic concepts in toxicology and environmental chemistry
11 General concepts

11.1 Pesticide regulation
11.2 Pesticide use in the United States
11.3 Dose-response relationships in toxicology
11.4 How much is a part per million?

12 Human health effects

12.1 Risk assessment
12.2 Epidemiology
12.3 Entry and fate of chemicals in humans
12.4 Manifestations of toxic effects
12.5 Toxic effects on the skin
12.6 Effects on the nervous system: cholinesterase inhibition
12.7 Carcinogenicity

13 Ecological and environmental effects

13.1 Movement of pesticides in the environment
13.2 Bioaccumulation
13.3 Ecological effects

Section IV: Appendices

Appendix A: Index of trade names
Appendix B: U.S. system-metric conversions
Appendix C: Glossary

© 2000 CRC Press LLC

Comprehensive Figure List

Chapter 1
There are no figures in Chapter 1.

Chapter 2
2.1 Generic pyrethroid structure
2.2 Allethrin
2.3 Cypermethrin
2.4 Esfenvalerate
2.5 Flucythrinate
2.6 Fluvalinate
2.7 Permethrin
2.8 Resmethrin
2.9 Rotenone
Chapter 3
3.1 Generic carbamate structure
3.2 Aldicarb
3.3 Bendiocarb
3.4 Carbaryl
3.5 Carbofuran
3.6 Chlorpropham
3.7 Fenoxycarb
3.8 Methomyl

3.9 Oxamyl
3.10 Propoxur
Chapter 4
4.1 Generic structures for thiocarbamates (A) and dithiocarbamates (B)
4.2 Butylate
4.3 EPTC
4.4 Mancozeb
4.5 Maneb
4.6 Metiram
4.7 Molinate
4.8 Thiram
4.9 Triallate
4.10 Zineb
4.11 Ziram
Chapter 5
5.1 Generic organophosphate structure
5.2 Azinphos-methyl

© 2000 CRC Press LLC

5.3 Bensulide
5.4 Chlorpyrifos
5.5 Coumaphos
5.6 Diazinon
5.7 Dichlorvos (DDVP)
5.8 Dimethoate
5.9 Disulfoton
5.10 Ethion
5.11 Fenamiphos
5.12 Fenthion

5.13 Fonofos
5.14 Isofenphos
5.15 Malathion
5.16 Methidathion
5.17 Methyl parathion
5.18 Mevinphos
5.19 Naled
5.20 Phorate
5.21 Phosmet
5.22 Propetamphos
5.23 Temephos
5.24 Terbufos
5.25 Trichlorfon
Chapter 6
6.1 Structures of generic dichlorophenylethanes (A) and cyclodienes (B)
6.2 Chlordane
6.3 Chlorobenzilate
6.4 Chlorothalonil
6.5 Dalapon
6.6 Dicofol
6.7 Dienochlor
6.8 Endosulfan
6.9 Heptachlor
6.10 Hexachlorobenzene
6.11 Lindane
6.12 Methoxychlor
6.13 PCNB (Quintozene)
6.14 Pentachlorophenol
Chapter 7
7.1 Generic structures for phenoxy herbicides (A) and

benzoic acid herbicides (B)
7.2 2,4-D
7.3 2,4-DB
7.4 Chloramben
7.5 DCPA
7.6 Dicamba
7.7 Fluazifop-p-butyl
7.8 MCPA
7.9 Quizalofop-p-ethyl

© 2000 CRC Press LLC

Chapter 8
8.1 Generic structures for triazines (A) and triazoles (B)
8.2 Amitrole
8.3 Atrazine
8.4 Cyanazine
8.5 Hexazinone
8.6 Metribuzin
8.7 Prometryn
8.8 Propazine
8.9 Simazine
8.10 Triadimefon
Chapter 9
9.1 Generic structures for phenylurea (A), sulfonylurea (B), and
benzoylphenylurea (C) compounds
9.2 Diflubenzuron
9.3 Diuron
9.4 Fluometuron
9.5 Linuron

9.6 Primisulfuron-methyl
9.7 Sulfometuron-methyl
9.8 Tebuthiuron
Chapter 10
10.1 Benomyl
10.2 Captan
10.3 Carboxin
10.4 Copper sulfate
10.5 Dinocap
10.6 Dodine
10.7 Imazalil
10.8 Iprodione
10.9 Metalaxyl
10.10 Thiabendazole
10.11 Vinclozolin
10.12 Acifluorfen
10.13 Alachlor
10.14 Ammonium sulfamate
10.15 Bentazon
10.16 Bromacil
10.17 Bromoxynil
10.18 Cacodylic acid
10.19 Clomazone
10.20 Dinoseb
10.21 Diquat dibromide
10.22 Glyphosate
10.23 Metolachlor
10.24 Napropamide
10.25 Oryzalin
10.26 Oxyfluorfen

10.27 Paraquat

© 2000 CRC Press LLC

10.28 Pendimethalin
10.29 Picloram
10.30 Pronamide
10.31 Propanil
10.32 Sethoxydim
10.33 Terbacil
10.34 Triclopyr
10.35 Trifluralin
10.36 Abamectin
10.37 Hydramethylnon
10.38 Methoprene
10.39 Sulfuryl fluoride
10.40 4-Aminopyridine
10.41 Daminozide
10.42 Diphacinone
10.43 Ethylene dibromide
10.44 Metaldehyde
10.45 Methyl bromide
10.46 Tributyltin
10.47 Zinc phosphide
Chapter 11
11.1 Dose-response relationships

© 2000 CRC Press LLC

Cumulative Table List

Table 1.1 EPA Toxicity Class and Signal Word in Relation to Acute Toxicity and
Skin/Eye Irritation
Table 1.2 Categories of Ecotoxicity
Table 1.3 Pesticide Persistence in Soils
Table 1.4 Categories of Solubility
Table 2.1 Pyrethroids
Table 3.1 Carbamates
Table 4.1.a Thiocarbamates
Table 4.2.b Dithiocarbamates
Table 5.1 Organophosphates
Table 6.1 Chlorinated Hydrocarbons
Table 7.1 Phenoxy and Benzoic Acids Herbicides
Table 8.1 Triazines and Triazoles
Table 9.1 Examples of Substituted Urea Compounds
Table 11.1 Measurements for Expressing Levels of Contaminants in Food
and Water
Table 11.2 Toxicity Rating Scale and Labeling Requirements for Pesticides
Table 11.3 Metric System Quantities
Table 12.1 General Toxicity Categories
Table 12.2 Plants and Pesticides That May Cause Primary Irritant Dermatitis
Table 12.3 Plants and Pesticides That May Cause Allergic Contact Dermatitis
(ACD)
Table 12.4 Plants and Medications That May Cause Photosensitization
When Ingested
Table 12.5 Plants That Cause Photosensitization by Contact
Table 12.6 Commonly Used Organophosphate (OP) Pesticides
Table 12.7 Commonly Used Carbamate Pesticides
Table 13.1 Pesticide Persistence in Soils

© 2000 CRC Press LLC

Section I
Introduction to pesticide profiles and
basic concept papers

© 2000 CRC Press LLC

chapter one

Introduction and profile
description

1.1Introduction

The purpose of this book is to provide user-friendly summaries of the environ-
mental, toxicological and chemical properties of pesticides for a variety of audiences,
both technical and nontechnical. To accomplish this, data about each active ingredient
have been gathered from a wide variety of sources and are provided to the reader
in each profile in both qualitative and quantitative formats.
To assist the reader in understanding exactly what information is provided in
each subsection of the profile and to appreciate what the quantitative equivalents
are to the qualitative statements in each of these summary documents, a detailed
description of the categories in each profile is provided in the following section of
this chapter. This description should assist the user in interpreting any part of an
individual profile that may not be clear.
The actual experimental results (e.g., specific effects at particular doses) are
presented for those with backgrounds in environmental toxicology and chemistry.
Lay people or those with other backgrounds are provided with general summary
statements regarding potential impacts of the compound on humans, wildlife, and

the environment.
This introductory chapter is followed by the section of the book containing the
pesticide profiles. This second section is divided into chapters containing summaries
of pesticides in the same or similar chemical groups. Thus, all of the organophos-
phates are in the same chapter. The rationale for this is that structural similarities
among members of a given group are usually related to similarities in biological
activity and environmental behavior.
Based on this concept, the beginning of each chapter in this section is devoted
to a general profile describing the common properties of the pesticides in that
chemical class. The purpose of this section is to assist the user in accessing at least
some information about an active ingredient even if the book does not contain a
profile specifically devoted to it. The reader does, however, need to know the chem-
ical group to which the pesticide belongs in order to choose the correct chapter to
examine.
At the end of each profile are sections dealing with physical constants and
exposure guidelines. These will be most useful to those with the relevant background
but not to the lay reader. The physical constants are quantitative descriptors of
properties (e.g., water solubility) that affect the behavior of the compound in both
the inanimate and animate environment. The exposure guidelines can be compared
to measured or calculated environmental exposures to determine if established expo-

© 2000 CRC Press LLC

sure limits have been exceeded. Also, for readers who would like additional infor-
mation, references are provided to support the experimental results, physical con-
stants, and exposure values.
The final chapter in this second part of the book contains profiles for pesticides
that fall into chemical groups in which relatively few members are used as pesticides.
In this chapter, the profiles are divided by how the pesticides are used: e.g., herbicide,
insecticide, etc. Since this chapter does not contain pesticides grouped by class, there

is no generic profile at the beginning of the chapter.
To complement the second part of the book, the third section of this volume
includes short summaries of important environmental toxicology and chemistry
concepts that can be used to better understand different aspects of the pesticide
profiles. For example, toxicological properties such as carcinogenicity and dermal
toxicity are described. As another, a description of the movement of pesticides in the
environment is provided.
The appendices are designed to enhance the value of this volume even further.
The first appendix lists a large number of trade names and the active ingredient(s)
that correspond to each of these products. The list includes trade names that are no
longer used because old products are consistently found in significant quantities on
farms, in business establishments, and in homes. Given the enormous number of
past and present trade names, this is not an exhaustive listing but should contain
the most commonly used products.
The second appendix provides a conversion table so that the readers can visu-
alize how the quantities described in metric units compare to units with which they
may be more familiar. The last appendix is a glossary of terms commonly used
throughout the book. The reader should be able to find the definition of any term
that is new to them in this section of the book.

1.2Description of profile categories

Each profile is divided into the following sections.
Trade or other names
Regulatory status
Introduction
Toxicological effects
Ecological effects
Environmental fate
Physical properties

Exposure guidelines
Basic manufacturer
References
These sections are described in more detail below.

Trade or other names

This section lists the most common trade and other names of products that
contain the pesticide active ingredient.

© 2000 CRC Press LLC

Regulatory status

This section indicates whether the active ingredient is a General Use Pesticide
(GUP) or a Restricted Use Pesticide (RUP) according to U.S. Environmental Protec-
tion Agency (EPA) guidelines, and its EPA toxicity class. According to EPA guide-
lines, GUPs may be sold to the public for general, unrestricted use. RUPs, on the
other hand, are for retail sale to and use by only certified applicators or persons
under their direct supervision. In some cases, all products containing a given active
ingredient are RUPs; in others, only some formulations or products are RUPs, and
the rest are for general use. In cases where one (or more) of the products or formu-
lations containing the pesticide active ingredient is (are) classified as RUP(s), the
active ingredient is generally referred to as a RUP.
The SIGNAL WORD (in capital letters) is also included in this section. The signal
word is based on the EPA toxicity class, and must be included by law on labels for
products containing the active ingredient. The EPA toxicity class is based on the
likely acute toxicity to humans (as determined in animal tests), potential for eye or
skin damage to applicators, ecological effects or potential to contaminate ground or
surface water. Table 1.1 shows the toxicity classes, the corresponding qualitative

descriptors, and the criteria for each class. In certain cases, different products or
formulations containing the same active ingredient will be in different EPA toxicity
classes based on toxicity test results. These differences may be due to the proportion
of the active ingredient in the final product or the type of formulation or product.

Introduction

This section describes the pesticide’s chemical family, its most common applica-
tions and uses, and the formulations in which it is available. Common formulation
types are liquids, wettable powder, emulsifiable concentrates, and dusts. There may
be a brief explanation of how the pesticide works to control the pest, or in what
circumstances it may be applied (e.g., pre- or post-emergence in the case of herbi-

Table 1.1

EPA Toxicity Class and Signal Word in Relation
to Acute Toxicity and Skin/Eye Irritation
EPA
toxicit
class
Toxicity
rating Signal word
Characteristic acute toxicity
in experimental animals

I Highly toxic DANGER —
POISON
Oral LD

50

: 0–50 mg/kg
Dermal LD

50

: 0–200 mg/kg
Inhalation LC

50

: 0–0.2 mg/L
Skin/eye irritation: severe
II Moderately
toxic
WARNING Oral LD

50

: >50–500 mg/kg
Dermal LD

50

: >200–2000 mg/kg
Inhalation LC

50

: >0.2–2.0 mg/L

Skin/eye irritation: moderate
III Slightly
toxic
CAUTION Oral LD

50

: 500–5000 mg/kg
Dermal LD

50

: >2000–20,000 mg/kg
Inhalation LC

50

: >2.0–20 mg/L
Skin/eye irritation: slight
IV Practically
nontoxic
None required Oral LD

50

: >5000 mg/kg
Dermal LD

50

: >20,000 mg/kg
Inhalation LC

50

: >20 mg/L
Skin/eye irritation: none

© 2000 CRC Press LLC

cides). Also contained in this section may be information on the compatibility of the
active ingredient with other pesticides with which it may commonly be mixed. In
general, the information presented pertains to the technical grade of the compound
unless otherwise noted.

Toxicological effects

Acute toxicity

Included in the acute effects section are those effects that have been noted in test
animals or in cases of accidental human exposure. Acute toxic effects are those caused
by exposures over brief periods of time, such as several minutes, hours, or 1 day.
Exposure may occur by the oral route (ingestion), dermal route (skin contact), or
inhalation.
The most commonly used measures of acute ingestion and skin toxicity are the
oral and dermal doses at which 50% of the test animals die within 14 days after
exposure to the test substance. These are also known as the oral median lethal dose
(or oral LD

50

) and the dermal median lethal dose (dermal LD

50

), respectively. This
dose is expressed as the amount of the pesticide active ingredient (or in some cases,
formulated product) applied (in milligrams) per kilogram of test animal body weight.
The acute toxicity via inhalation is assessed as the airborne concentration of the
test substance that is lethal to 50% of the test animals over a specific exposure time
(in many cases, 4 hours). This is often called the median lethal concentration, and is
abbreviated LC

50

. It is expressed in terms of the amount of pesticide or formulation
(in milligrams) in a given volume of air (either in liters, L, or cubic meters, m

3

). It is
important to remember that the LC

50

refers to the airborne concentration of the
substance to which the animal is exposed, not the dose to the animal.

Chronic toxicity

The chronic toxicity section summarizes the data from animal studies of pesticide
effects, as well as data from human epidemiological studies where available. Chronic
effects refer to those effects that occur due to multiple or continuous exposures for
extended periods of time, such as several weeks, months, or years. In many cases,
there will be a long delay (latency period) between the time of the initial exposure(s)
and the onset of health problems. In addition to the general chronic effects identified
in human epidemiology and animal studies, data on reproductive, teratogenic,
mutagenic (and genotoxic), and carcinogenic effects are presented in separate sub-
sections. In the chronic toxicity section, and in all of its subsections, special attention
is paid to the dose levels at which effects were observed in animal studies and their
relevance to human health.

Reproductive effects

This section summarizes the results of studies of the effects of pesticide exposure
on the ability of test animals to successfully produce normal numbers of healthy
offspring. Female and/or male animals are fed a range of doses of the pesticide and
then observations are made to determine whether they are fertile and produce live
offspring, often through several generations.

Teratogenic effects

This section summarizes studies of the effects of pesticide exposure on the
viability and development of test animal offspring. Parent animals receive various

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doses of the pesticide. Their offspring are examined for the presence of structural
birth defects and abnormal development.

Mutagenic effects

This section summarizes the results of tests to examine whether pesticide expo-
sures result in changes in gene structure or function in biological systems. Tests may
be performed on bacteria, isolated animal or human cell cultures, as well as in
experimental animals to determine if the pesticide causes changes in the chemical
structure (mutation) of genetic material (DNA), aberrations in chromosome structure,
alterations in the synthesis and repair of DNA, or proper gene expression.

Carcinogenic effects

This section summarizes results of long-term animal studies, generally extending
over a lifetime, performed to determine the cancer-causing potential of the pesticide.
Effects such as abnormal cell growth, cellular changes related to cancer, and tumor
formation are commonly monitored and reported.

Organ toxicity

This section describes the organs or organ systems that are primarily affected
by chronic exposure to the pesticide.

Fate in humans and animals

The section on the fate of a pesticide in humans or animals includes information
regarding the absorption of the pesticide, its distribution throughout the body, and
how easily it may be degraded and eliminated from the body. Where available, data
are presented on the route(s) of elimination, the biological half-life of the pesticide
(how long it will take for one half the amount present in the system to be degraded
and/or eliminated), and the principal breakdown products of the pesticide.

Ecological effects

Effects on birds

This section summarizes the toxicity of acute oral (single administration) or
subchronic dietary (approximately 8 days) pesticide exposure on birds. Toxicity is
measured by the median lethal oral dose, the oral LD

50

, or the median lethal dietary
concentration, or dietary LC

50

. These refer, respectively, to the dose or concentration
at which 50% of the test birds die. Here again, it is important to remember that the
LD

50

is expressed in terms of the amount of pesticide or formulation per kilogram
of the test bird, whereas the LC

50

represents a concentration, in this case the concen-
tration of the pesticide in the test bird diet. To avoid confusion, the oral LD

50

is
expressed in units of milligrams per kilogram, and the dietary LC

50

is expressed as
parts per million (ppm). The toxicity of pesticide active ingredient is qualitatively
classified according to the toxicity categories shown in Table 1.2.

Effects on aquatic organisms

This section summarizes results of acute toxicity testing on fish and other aquatic
species. Results are reported as the median lethal concentration (LC

50

), or the water
concentration that kills 50% of the exposed individuals (either fish or other aquatic
species) within a specific time period (typically 48 or 96 hours). The toxicity categories

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for aquatic organisms are also included in Table 1.2. The toxicity to fish or other
aquatic organisms may be influenced by factors such as pH, temperature, total
dissolved oxygen, and total water hardness. Where available, the bioconcentration
factor for fish or other aquatic organisms is also included.

Effects on other organisms (non-target species)

Some pesticides, especially if applied incorrectly or at excessive rates, affect
organisms other than the intended pest; these are referred to as non-target species.
In some cases, these species may be economically important (e.g., bees) or ecologi-
cally important (e.g., earthworms or non-target plants). This section summarizes the
results of studies on the effects of the pesticide on these non-target organisms,
especially bees.

Environmental fate

Breakdown in soil and groundwater

This section summarizes the results of studies on pesticide persistence, soil
binding, mobility, and microbial degradation, as well as the potential for pesticides
or harmful degradates to leach into groundwater. Data describing the frequency of
detection and concentration of the pesticide in soil and groundwater samples are
included if available. The soil persistence of the pesticide is qualitatively classified
on the basis of observed field half-life as shown in Table 1.3.
Pesticide behavior in a specific soil/groundwater environment will depend on
many factors, including the soil type, temperature, vapor pressure, the amounts of
sunlight and rain, the water solubility of the pesticide, the type of soil, and the rate
of application. Thus, information presented in each profile should serve as a means
of comparison between pesticides and should not be intrepreted in an absolute
fashion.

Table 1.2

Categories of Ecotoxicity
Toxicity category
Birds acute oral LD

50


(mg/kg)
Bird dietary LC

50


(ppm)
Fish water LC

50


(mg/L)

Very highly toxic <10 <50 <0.1
Highly toxic 10–50 50–500 0.1–1
Moderately toxic >50–500 >500–1000 >1–10
Slightly toxic >500–2000 >1000–5000 >10–100
Practically nontoxic >2000 >5000 >100

Table 1.3

Pesticide Persistence in Soils
Persistence
categories
Time required for 50% of the
applied pesticide to degrade at or

near the soil surface (half-life)
Examples of pesticide classes (there
are several exceptions in each class)

Low persistence Less than 30 days Carbamate and organophosphate
herbicides
Moderate
persistence
30–100 days Triazine, urea, amide, and phenoxy
herbicides
High persistence Greater than 100 days Chlorinated hydrocarbon
insecticides

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Breakdown in water

Information on pesticide behavior in the surface water environment is summa-
rized here. This section describes how easily the pesticide dissolves and by which
pathways it is broken down or eliminated from surface waters. Such factors as water
pH, sunlight, and available oxygen may affect the persistence of the pesticide in
water. If available, this section may include results of studies on the concentrations
of the pesticide found in surface water.

Breakdown in vegetation

This section summarizes data on how various plants take up, distribute, and
process or eliminate the pesticide. For example, the pesticide may damage plant
leaves or stems, or it may be degraded as it travels within the plant.

Physical properties

This section describes the chemical and physical characteristics of the pesticide
active ingredient. This includes the physical appearance of the pure or technical
grade chemical, Chemical Abstracts Service number, molecular weight, solubilities
in water and various other solvents (see Table 1.4), melting point, and vapor pressure.
Also included where available are the octanol–water partition coefficient (K

ow

) and
the soil adsorption coefficient.
The soil adsorption coefficient depends on several soil properties, including
organic matter content, organic matter type, particle size distribution, clay mineral
composition, and pH. Where available, the reported soil adsorption coefficient is the
K

oc

, which takes into account the soil organic matter content. Where this is not
available, the unadjusted observed soil adsorption coefficient, K

d

, is reported. The
values for these variables are experimentally determined, and reported values may
in many cases consist of the most representative value.

Exposure guidelines

The exposure guidelines are the maximum acceptable doses or levels of exposure.
Exposure guidelines have been developed by different agencies and organizations
such as the EPA, the U.S. Occupational Safety and Health Administration (OSHA),
and the American Council of Government Industrial Hygienists (ACGIH).

EPA guidelines and standards

Guidelines developed by the EPA include reference dose (RfD) and the Health
Advisory level (HA). The Reference Dose (RfD) is defined as the dose of the admin-

Table 1.4



Categories of Solubility
Rating Solubility at 20–30

°

C (room temperature)

Insoluble Less than 1 mg/L
Slightly soluble 1–100 mg/L
Soluble 100–10,000 mg/L
Very soluble Greater than 10,000 mg/L

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istered chemical that during an entire lifetime, appears to be without appreciable
risk. RfDs are generally based on data from animal studies that are adjusted for

scientific uncertainties to determine levels which are unlikely to result in harmful
effects in human populations. A margin of safety for both adults and children is built
into these values.
Health Advisory levels (HAs) refer to drinking water contaminant levels that
would not be anticipated to cause adverse health effects over a given exposure
period. A margin of safety to account for scientific uncertainty is built into these
values, again using animal data as a foundation. Drinking water Health Advisory
levels are developed for exposures of 1-day, 10-days, long-term (about 7 years), and
lifetime duration.
Health Advisories do not carry the force of law. In cases where a legally enforce-
able drinking water standard has been established, it is presented in the profile
instead of the HA.
The maximum contaminant level (MCL) is the standard established under the
Safe Drinking Water Act for the maximum permissible level of a contaminant in
drinking water that is delivered to the users of a public water system. In cases where
a contaminant is a known or probable human carcinogen, a zero-tolerance approach
is used, and the MCL is determined by the limitations of quantitative chemical
analysis.

OSHA standards

Under the Occupational Safety and Health Act (OSHAct), OSHA has established
acceptable levels of exposure to airborne contaminants in the workplace environ-
ment. These are known as Permissible Exposure Limits (PELs), which have the force
of law in occupational situations where the OSHAct is applicable. PELs are intended
for application in the occupational environment, and assume that exposure occurs
8 hours a day for 40 hours a week. OSHA PELs are developed using evidence from
human health studies as well as animal studies, allowing for scientific uncertainty.
Where the PEL is not available, the ACGIH Threshold Limit Value (TLV) is
presented.

ACGIH guidelines

The ACGIH has established maximum workplace concentrations of air contam-
inants to which nearly all workers may be repeatedly exposed without adverse effect.
These are known as the ACGIH Threshold Limit Values (TLVs). Like OSHA PELs,
TLVs assume exposure periods of 8 hours within a 40-hour work week. ACGIH also
publishes Short Term Exposure Limits (STELs), to be exceeded not more than four
times in a day, with at least 1 hour between successive excursions.

Other guidelines

A guideline used by both the U.S. Food and Drug Administration and the World
Health Organization is the Acceptable Daily Intake (ADI). The ADI is obtained in a
similar fashion to the RfD using animal study data, and incorporating scientific
uncertainty. There may be some differences between the ADI and RfD because of
the data used and/or the amount of uncertainty that is thought to exist by different
agencies.

Basic manufacturer

The name, address, and phone number of the primary manufacturer of the
pesticide are listed here. The emergency phone number of the primary manufacturer
is included if available. The company listed here may be the firm registered with the
U.S. EPA to process and market the product in the United States and not the actual
producer.

1.3Disclaimer

The information provided in this book does not replace or supersede the infor-

mation on the pesticide product labeling or other regulatory requirements.

© 2000 CRC Press LLC