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GLYPHOSATE REREGISTRATION ELIGIBILITY TEAM

Office of Pesticide Programs:

Special Review and Reregistration Division

Eric Feris .................................................. Reregistration Branch

Health Effects Division

Jane Smith ........................................ Chemical Coordination Branch

Krystyna Locke .............................................. Toxicology Branch I

Jeff Evans ........................... Occupational and Residential Exposure Branch

Randolph Perfetti ......................... Chemistry Branch - Reregistration Support

Biological and Economic Analysis Division

James G. Saulmon ..................................... Biological Analysis Branch

Eric Maurer ........................................... Economic Analysis Branch 

Environmental Fate and Effects Division

Candace Brassard ..................................... Ecological Effects Branch

Kevin Poff ............................. Environmental Fate and Groundwater Branch

Bernice Slutsky ............................ Science Analysis and Coordination Staff

Registration Division

Mark Perry .......................................... Registration Support Branch

Karen P. Hicks ....................................... Fungicide-Herbicide Branch

Policy and Special Projects Staff

Jean Frane ............................. Food Safety & Regulation Tracking Section

Office of General Counsel:

Pesticides and Toxic Substances Division

Debra Burton ................................................. Pesticides Branch

Office of Compliance Monitoring:

Policy and Grants Division

Beverly Updike ................................... FIFRA Policy & Analysis Branch
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TABLE OF CONTENTS

GLOSSARY OF TERMS AND ABBREVIATIONS .......................... vi

EXECUTIVE SUMMARY .................................................. viii

I. INTRODUCTION ..................................................... 1

II. CASE OVERVIEW ................................................... 2

A. Chemical Overview ............................................... 2

B. Use Profile ....................................................... 2

C. Estimated Usage of Pesticide ..................................... 7

D. Data Requirements ............................................... 9

E. Regulatory History ............................................... 9

III. SCIENCE ASSESSMENT ........................................... 9

A. Product Chemistry ............................................... 9

B. Human Health Assessment ....................................... 10

1. Toxicology Assessment ....................................... 10

a. Acute Toxicity ......................................... 10

b. Subchronic Toxicity .................................... 11

c. Chronic Toxicity ....................................... 12

d. Carcinogenicity ........................................ 13

e. Developmental Toxicity ................................. 15
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f. Reproductive Toxicity ................................... 16

g. Mutagenicity .......................................... 17

h. Metabolism ........................................... 17

i. Neurotoxicity .......................................... 18

j. Other Toxicological Endpoints ........................... 19

k. Reference Dose ....................................... 19

2. Exposure Assessment ........................................ 20

a. Dietary Exposure ...................................... 20

b. Occupational and Residential ............................ 21

3. Risk Assessment ............................................ 23

a. Dietary ............................................... 23

b. Occupational and Residential ............................ 24

c. Dietary Exposure References ............................ 24

C. Environmental Assessment ....................................... 30

1. Environmental Fate .......................................... 30

a. Environmental Fate and Transport ........................ 30

b. Environmental Fate and Groundwater Assessment .......... 37

2. Ecological Effects ........................................... 37

a. Ecological Hazard ..................................... 37

b. Ecological Effects Risk Assessment ...................... 53

IV. RISK MANAGEMENT AND REREGISTRATION DECISION ........ 57
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A. Determination of Eligibility ........................................ 57

1. Eligibility Decision ........................................... 57

2. Eligible and Ineligible Uses ................................... 58

B. Regulatory Position .............................................. 58

1. Tolerance Re-assessment .................................... 58

2. Labeling Rationale ........................................... 70

3. Endangered Species Statement ............................... 70

V. ACTIONS REQUIRED BY REGISTRANTS.......................... 70

A. Manufacturing-Use Products ...................................... 70

1. Additional Generic Data Requirements .......................... 70

2. Labeling Requirements for Manufacturing-Use Products ........... 71

B. End-Use Products ................................................ 71

1. Additional Product-Specific Data Requirements .................. 71

2. Labeling Requirements for End-Use Products .................... 72

a. Nonaquatic ........................................... 72

b. Aquatic .............................................. 72

C. Existing Stocks .................................................. 74

VI. APPENDICES ........................................................ 74

Appendix A - Use Patterns Subject to Reregistration

Appendix B - Table of the Generic Data Requirements and Studies Used to Make the

Reregistration Decision
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Appendix C - Citations Considered to be Part of the Data Base Supporting the

Reregistration of Glyphosate

Appendix D - List of Available Related Documents

Appendix E - Pesticide Reregistration Handbook

Appendix F - Generic and Product-Specific Data Call-In 

! Attachment 1 - Chemical Status Sheet

! Attachment 2 - Generic Data Call-In and Product Specific Data Call-In Response

Forms with Instructions

! Attachment 3 - Generic Data Call-In and Product Specific Data Call-In

Requirements Status and Registrants' Response Forms with

Instructions

! Attachment 4 - EPA Grouping of End Use Products for Meeting Acute Toxicology

Data Requirements. 

! Attachment 5 - EPA Acceptance Criteria

! Attachment 6 - List of all Registrant(s) sent this Data Call-In

! Attachment 7 - Cost Share/Data Compensation Forms
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GLOSSARY OF TERMS AND ABBREVIATIONS

a.i. Active Ingredient

CAS Chemical Abstracts Service

CFR Code of Federal Regulations

CSF Confidential Statement of Formula

EEC Estimated Environmental Concentration. The estimated pesticide concentration

in an environment, such as a terrestrial ecosystem.

EP End-Use Product

EPA U.S. Environmental Protection Agency

FIFRA Federal Insecticide, Fungicide, and Rodenticide Act

FFDCA Federal Food, Drug, and Cosmetic Act

FR Federal Register

HDT Highest Dose Tested

LC50 Median Lethal Concentration. A statistically derived concentration of a

substance that can be expected to cause death in 50% of test animals. It is

usually expressed as the weight of substance per weight or volume of water or

feed, e.g., mg/l or ppm.

LD50 Median Lethal Dose. A statistically derived single dose that can be expected to

cause death in 50% of the test animals when administered by the route

indicated (oral or dermal). It is expressed as a weight of substance per unit

weight of animal, e.g., mg/kg.

LDlo Lethal Dose-low. Lowest Dose at which lethality occurs

LEL Lowest Effect Level
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MATC Maximum Allowable Toxicant Concentration: A range at which the pesticide

causes no effect (NOEL) and the lowest dose at which an effect was observed

(LOEL).

MP Manufacturing-Use Product

MPI Maximum Permissible Intake

MRID Master Record Identification (number). EPA's system of recording and tracking

studies submitted.

N/A Not Applicable

NPDES National Pollutant Discharge Elimination System

NOEL No Observed Effect Level

OPP Office of Pesticide Programs

PADI Provisional Acceptable Daily Intake

ppm Parts Per Million

REI Restricted Entry Interval

RfD Reference Dose

RS Registration Standard

TD Toxic Dose. The dose at which a substance produces a toxic effect.

 

TC Toxic Concentration. The dose at which a substance produces a toxic effect. 

TMRC Theoretical Maximum Residue Contribution.

WPS Worker Protection Standard
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EXECUTIVE SUMMARY

This document addresses the reregistration eligibility of the pesticide glyphosate. 

There are 63 glyphosate-containing products registered for use in the United States. The

isopropylamine salt of glyphosate, the active ingredient in 53 of these registrations, is used as

a herbicide to control a number of broadleaf weeds and grasses. The principal food use sites

include corn, wheat, sorghum, citrus and stone fruits, potatoes and onions, asparagus, coffee,

peanuts, and pineapples. There are also a number of non-food use sites including

ornamental, turf, forestry, and industrial rights-of-way. Two registrations contain the sodium

salt of glyphosate and are used in sugarcane fields. In addition there are seven

herbicide/plant regulation products containing the monoammonium salt of glyphosate which

were registered subsequent to the development of List A and are not a subject of this RED. 

Except where explicitly noted otherwise, the term "glyphosate," when used in this document,

refers to either the technical acid or the isoproplyamine and sodium salts of glyphosate. 

However, the monoammonium salt is included in the tolerance expression. Available data

have been sufficient to allow re-assessment of existing tolerances, which includes the

monoammonium salt of glyphosate.

In June 1986, the Agency issued the document "Registration Standard for Pesticide

Products Containing Glyphosate as the Active Ingredient" (NTIS #PB87-103214). The

Registration Standard required scientific studies in the areas of phytotoxicity, environmental

fate, toxicology, product chemistry, and residue chemistry. With the exception of a few waived

studies, all of the data required have been submitted. After completing its review for

reregistration, the Agency now concludes that the data base on glyphosate is substantially

complete. 

Based on the results of its reregistration review, EPA has concluded that all registered

uses of glyphosate are eligible for reregistration. The Agency has classified glyphosate as a

Group E carcinogen (signifies evidence of non-carcinogenicity in humans). A Reference

Dose of 2 mg/kg/day has been recommended. This proposal is based on a maternal NOEL

of 175 mg/kg/day from a rabbit developmental toxicity study and an uncertainty factor of 100. 

The dietary risk assessment is based on a worst-case scenario, assuming treatment of 100%

of acreage and highest legal residue values which likely result in an overestimation of

exposure and risk. Even with these values, however, dietary exposure is expected to be

minimal. There are 85 tolerances established for various crops and crop groups as well as

Federal Food, Drug, and Cosmetic Act §409 tolerances for processed food and animal feed

and animal tolerances. A re-assessment of tolerances is included in this document and there

are no major changes in the previously-established tolerances. Studies show that glyphosate

is no more than slightly toxic to birds and is practically non-toxic to fish and honeybees. 

However, a toxic inert in glyphosate end use products necessitates the labelling of some
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products "toxic to fish" since some glyphosate products are applied directly to aquatic

environments. 

The Agency does have concerns regarding the potential hazard to endangered plant

species and the Houston toad. However, the Agency is not requiring any modification of use

or label changes in this document. A Federal Register Notice on the Endangered Species

Protection Plan and subsequent guidance to registrants will impose appropriate exposure

mitigation measures for areas where endangered plant species and the Houston toad may be

encountered. In addition, there have been a number of reported incidents of spray drift

damage to non-target crops. Spray drift studies are required as is a Tier II Vegetative Vigor

study. These studies are not part of the target data base for reregistration of glyphosate. 

Before reregistering each product, the Agency is requiring that product specific data in

the areas of product chemistry and acute toxicology, revised Confidential Statements of

Formula, and revised labeling be submitted within eight (8) months of the issuance of this

document. In an effort to reduce the time, resources, and number of animals needed to fulfill

the acute toxicology data requirements for glyphosate-containing end use products, the

Agency has "batched" products considered to be similar with respect to acute toxicity testing

requirements. After reviewing these data and the revised labels, the Agency will determine

whether to re-register a product based on whether or not that product meets the requirements

in Section 3(c)(5) of FIFRA. End use products containing glyphosate in combination with

other active ingredients will not be re-registered until the Reregistration Eligibility Decisions

for all active ingredients contained in that product are issued and all the active ingredients

contained in the product are also eligible for reregistration. However, product specific data for

these products are being called in at this time.
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1

 EPA's reviews of data on the set of registered uses considered for EPA's analysis may be obtained from the OPP Public 

Field Operations Division (H7506C), Office of Pesticide Programs, EPA, Washington, DC 20460.

1

I. INTRODUCTION

In 1988, the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) was

amended to accelerate the reregistration of products with active ingredients registered

prior to November 1, 1984. The amended Act provides a schedule for the reregistration

process to be completed in nine years. There are five phases to the reregistration

process. The first four phases of the process focus on identification of data requirements

to support the reregistration of an active ingredient and the generation and submission of

data to fulfill the requirements. The fifth phase is a review by the U.S. Environmental

Protection Agency (referred to as "the Agency") of all data submitted to support

reregistration.

FIFRA Section 4(g)(2)(A) states that in Phase 5 "the Administrator shall determine

whether pesticides containing such active ingredient are eligible for registration" before

calling in data on products and either re-registering products or taking "other appropriate

regulatory action." Thus, reregistration involves a thorough review of the scientific data

base underlying a pesticide's registration. The purpose of the Agency's review is to

reassess the potential hazards arising from the currently registered uses of the pesticide;

to determine the need for additional data on health and environmental effects; and to

determine whether the pesticide meets the "no unreasonable adverse effects" criterion of

FIFRA.

This document presents the Agency's decision regarding the reregistration

eligibility of the registered uses of the isopropylamine salt and the sodium salt formulations

of glyphosate. Except where explicitly noted otherwise, the term "glyphosate," when used

in this document, refers to either the technical acid or the isoproplyamine and sodium salts

of glyphosate but does not cover the monoammonium salt products since the compound

was not included in the Federal Register publication of List A. The document consists of

six sections. Section I is the introduction. Section II describes glyphosate, its uses, data

requirements and regulatory history. Section III discusses the human health and

environmental assessment based on the data available to the Agency. Section IV

presents the reregistration decision for glyphosate. Section V discusses the reregistration

requirements for glyphosate. Finally, Section VI is the Appendices which support this

Reregistration Eligibility Document. Additional details concerning the Agency's review of

applicable data are available on request.1
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II. CASE OVERVIEW

A. Chemical Overview

The following active ingredient(s) are covered by this Reregistration

Eligibility Document:

Common Name: glyphosate

Chemical Name: N-phosphonomethyl glycine

CAS Registry Number: 38641-94-0

OPP Chemical Codes: 103601 (isopropylamine salt)

103603 (sodium salt)

Empirical Formula: C3H8NO5P

Trade Names: Roundup, Rodeo, Shackle

Basic Manufacturer: Monsanto Company

800 N. Lindbergh Blvd.

St. Louis, MO 63167

B. Use Profile

The following is information on the current registered uses with an overview

of use sites and application methods. A detailed table of the uses of glyphosate

is given in Appendix A.

Chemical: glyphosate, isopropylamine salt (103601)

Type of Chemical: herbicide

Mechanism of Action: not known at this time, but it appears to inhibit the

aromatic amino acid biosynthesis pathway and may

inhibit or repress chlorismate mutase and/or

prephenate hydratase.
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Use groups and sites:

AQUATIC FOOD CROP: 

agricultural drainage systems, irrigation systems, lakes/ponds/reservoirs (with

human or wildlife use), streams/rivers/channeled water. 

AQUATIC NON-FOOD INDUSTRIAL:

aquatic areas/water, drainage systems, sewage systems.

AQUATIC NON-FOOD OUTDOOR:

aquatic areas/water

FORESTRY:

conifer release, forest plantings (reforestation programs), forest trees (all or

unspecified). 

GREENHOUSE FOOD CROP:

greenhouses-in use.

INDOOR NON-FOOD:

greenhouse-empty.

OUTDOOR RESIDENTIAL:

household/domestic dwellings outdoor premises.

TERRESTIAL FEED CROP:

alfalfa, barley, beans, buckwheat, corn, grass forage/fodder/hay, lentils, millet

(proso), nongrass forage/fodder/straw/hay, oats, pastures, rye, sorghum, wheat.

TERRESTRIAL FOOD CROP:

acerola (West Indies Cherry), apricot, artichoke (Jerusalem), asparagus, atemoya,

avocado, banana, beech nut, beets, blackberry, blueberry, boysenberry, brazil nut,

breadfruit (breadnut), broccoli, brussels sprouts, butternut, cabbage, cabbage

(Chinese), carambola (jalea), carrot (including tops), cashew, cauliflower, celery,

chard (swiss), cherimoya, cherry, chestnut, chicory, cocoa, coffee, collards,

cranberry, cress (water), cucumber, currant, date, dewberry, eggfruit tree (canistel),

eggplant, elderberry, endive (escarole), fig, filbert (hazelnut), garlic, gooseberry,

gourds, groundcherry (strawberry tomato/tomatillo), guava, hickory nut, horseradish,

huckleberry, jaboticaba, jackfruit, kale, kitembilla (ceylon gooseberry), kiwi fruit,

kohlrabi, leek, lettuce, litchi nut, loganberry, longan, loquat, macadamia nut
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(bushnut), mamey (mammee apple), mango, marmaladebox (genipapo), mayhaw

(hawthorn), melons, melons (cantaloupe), melons (honeydew), melons (mango),

melons (musk), melons (water), melons winter

(casaba/crenshaw/honeydew/persian), mustard, nectarine, okra, olive, onion,

papaya, parsley, passion fruit, peach, pear, pecan, pepper, persimmon, pistachio,

plantain, plum, pomegranate, prune, pumpkin, quince, radish, raspberry (black,

red), rhubarb, rutabaga, sapodilla, sapota (white), soursop, spinach, squash

(summer), squash (winter), sugar apple (custard apple), sweet potato, tamarind,

taro, tea, walnut (English/black), yam.

TERRESTRIAL FOOD + FEED CROP:

agricultural fallow/idleland, almond, apple, barley, beans, beets (unspecified),

buckwheat, calamondin, citron (citrus), citrus hybrids other than tangelo, corn

(unspecified), corn (field), cotton (unspecified), grapefruit, grapes, kumquat, lemon,

lentils, lime, millet proso (broomcorn), mustard, oats, orange, parsnip, peanuts

(unspecified), peas (unspecified), pineapple, potato (white/irish), pummelo

(shaddock), rape, rice, rice (wild), rye, sorghum, soybeans (unspecified), sugar

beet, sugarcane, tangelo, tangerines, tomato, triticale, turnip, wheat.

TERRESTRIAL + GREENHOUSE NON-FOOD CROP:

ornamental and/or shade trees, ornamental woody shrubs and vines.

TERRESTRIAL NON-FOOD CROP:

agricultural fallow/idleland, agricultural rights-of-way/fencerows/hedgerows,

agricultural uncultivated areas, airports/landing fields, christmas tree plantations,

golf course turf, industrial areas (outdoor), nonagricultural outdoor

buildings/structures, nonagricultural rights-of-way/fencerows/hedgerows,

nonagricultural uncultivated areas/soils, ornamental and/or shade trees, ornamental

lawns and turf, ornamental woody shubs and vines, paths/patios, paved areas

(private roads/sidewalks), recreational areas, urban areas.

TERRESTRIAL NON-FOOD+OUTDOOR RESIDENTIAL:

ornamental and/or shade trees, ornamental herbaceous plants, ornamental lawns

and turf, ornamental woody shubs and vines.
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Pests: many broadleaf and grass weeds

Formulation types registered:

SINGLE ACTIVE INGREDIENT:

Form Not Identified/Liquid

53.50 % glyphosate, isopropylamine salt

41.00 % glyphosate, isopropylamine salt

Form Not Identified/Solid

76.00 % glyphosate, isopropylamine salt

Liquid-Ready to Use

19.70 % glyphosate, isopropylamine salt

18.30 % glyphosate, isopropylamine salt

15.80 % glyphosate, isopropylamine salt

 1.00 % glyphosate, isopropylamine salt

 0.96 % glyphosate, isopropylamine salt

 0.50 % glyphosate, isopropylamine salt

Manufacturing Use

94.00 % glyphosate, isopropylamine salt

Pelleted/Tableted

83.50 % glyphosate, isopropylamine salt

60.00 % glyphosate, isopropylamine salt

Pressurized Liquid

 0.96 % glyphosate, isopropylamine salt

 0.75 % glyphosate, isopropylamine salt

Soluble Concentrate/Liquid

62.00 % glyphosate, isopropylamine salt

53.80 % glyphosate, isopropylamine salt

41.50 % glyphosate, isopropylamine salt

41.00 % glyphosate, isopropylamine salt

28.60 % glyphosate, isopropylamine salt

25.10 % glyphosate, isopropylamine salt

18.00 % glyphosate, isopropylamine salt

10.00 % glyphosate, isopropylamine salt

 8.20 % glyphosate, isopropylamine salt

 7.00 % glyphosate, isopropylamine salt

 5.00 % glyphosate, isopropylamine salt

Soluble Concentrate/Solid

93.96 % glyphosate, isopropylamine salt
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MULTIPLE ACTIVE INGREDIENT:

Liquid-Ready to Use 

12.40 % glyphosate, isopropylamine salt + 1 other A.I.

 7.70 % glyphosate, isopropylamine salt + 1 other A.I.

 0.50 % glyphosate, isopropylamine salt + 1 other A.I.

 0.25 % glyphosate, isopropylamine salt + 1 other A.I.

Soluble Concentrate/Liquid

16.50 % glyphosate, isopropylamine salt + 1 other A.I.

14.80 % glyphosate, isopropylamine salt + 1 other A.I.

13.30 % glyphosate, isopropylamine salt + 1 other A.I.

12.90 % glyphosate, isopropylamine salt + 1 other A.I.

Methods and rates of application (Given in maximum active (acid equivalent (ae))

rates, except as otherwise noted):

Broadcast or spray; for example as needed: 

Form Not Identified/Liquid - rates were not specified in

Appendix A dated 8/12/93;

Form Not Identified/Solid - rates were not specified in

Appendix A dated 8/12/93;

Liquid-Ready to Use - applied at rate of 3.08 lb ae/A;

Pelleted/Tableted - applied as a spot treatment, for example from a hand held

sprayer;

Pressurized Liquid - applied as a spot treatment, for example from an aerosol can;

Soluble Concentrate/Liquid - applied at rate of 7.5 lb ae/A;

Soluble Concentrate/Solid - applied at rates of 0.09 gal ae/A;

Chemical: glyphosate, sodium salt (103603)

Type of Chemical: plant regulator

Mechanism of Action: modifies plant growth; hastens fruit ripening
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Use Groups and Sites:

TERRESTRIAL FOOD + FEED CROP:

peanuts (unspecified); sugarcane

Formulation Types Registered:

SINGLE ACTIVE INGREDIENT:

soluble concentrate/solid

75.0% glyphosate, sodium salt

Methods and Rates of Application:

soluble concentrate/solid - applied as ground spray at peanut bloom stage at

0.0375 lb a.i./A in 10 gal water;

soluble concentrate/solid - applied as aerial spray at sugarcane ratoon stage at

0.525 lb a.i./A in 5 gal water.

Use Limitations:

sugarcane - 21 days preharvest interval; peanuts - 84 days preharvest interval. Do

not apply this product through any type of irrigation system.

C. Estimated Usage of Pesticide

This section summarizes the best estimates available for the pesticide uses

of glyphosate. These estimates are derived from a variety of published and

proprietary sources available to the Agency. The data, reported on an aggregate

and site (crop) basis, reflect annual fluctuations in use patterns as well as the

variability in using data from various information sources.

The table below summarizes glyphosate useage by site.

Glyphosate Usage

Site Multiple Acres

Treated (x1000)

Pounds AI

(x1000)

non-ag areas unknown 3000-7000

almonds 350-390 500-550
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apples 75-275 65-200

barley 550-600 275-325

cherries 15-95 20-125

corn, field 1,300-1,700 1,100-1,200

cotton 300-1,000 225-375

hay/pasture 3,000-3,500 1,500-1,700

dry edible beans/peas 50 20

grapefruit 70-140 183-375

grapes 45-550 25-265

lemons 5-75 10-70

other ag sites 3,000-3,500 1,000-1,500

oranges 300-600 650-1,300

peaches 10-150 10-110

peanuts 10-30 5-10

pears 15-50 15-65

pecans 5-300 5-150

plums/prunes 5-80 5-40

rice 30-55 25-30

sorghum 450-550 100-150

soybeans 2,600-4,800 2,200-2,400

spring wheat 200-225 50-60

sugarcane 10-70 5-35

potatoes 20-40 25-30

sunflowers 60-70 25-40

sweet corn 10-30 5-15

tomatoes 30-40 15-30

green beans/peas 20-40 5-20

walnuts 150-175 100-125

winter wheat 350-1,150 250-450
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TOTAL 12,985-20,280 11,398-18,745

In a typical year between 1989 and 1991, approximately 13-20 million acre

treatments were made with 18.7 million pounds active ingredient. Hay/pasture

(20%), soybeans (20%), field corn (9%), and other agricultural areas (20%)

comprise 71% of the total acreage treated with glyphosate. Non-agricultural areas

(33%), soybeans (15%), hay/pasture (11%), and corn (8%) comprise 67% of the

total pounds of active ingredient applied. 

D. Data Requirements

Data required in the June 1986 Registration Standard for glyphosate include

studies on product chemistry, ecological effects, environmental fate, toxicology, and

residue chemistry. These data were required to support the uses listed in the

Registration Standard. Appendix B includes all data requirements identified by the

Agency for currently registered uses needed to support reregistration.

E. Regulatory History

Glyphosate is registered in the United States for use as a herbicide. The

June 1986 Registration Standard evaluated the studies currently on file at the

Agency and required submission of further data. This Reregistration Eligibility

Document reflects an assessment of all data which were submitted in response to

the Registration Standard.

III. SCIENCE ASSESSMENT

A. Product Chemistry
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Empirical Formula: C3H8NO5P

Molecular Weight: 169.07

CAS Registry No.: 38641-94-0

Shaughnessy No.: 103601 (isopropylamine salt, IPA)

103603 (sodium salt)

The glyphosate (N-phosphonomethyl glycine) salts are nonselective

herbicides and plant growth regulators. The technical isopropylamine salt (IPA) is

a white crystalline solid with a melting point of 200EC and a bulk density of 1.74

lb/ft3. It is 1% soluble in water at 25EC and insoluble in ethanol, acetone, or

benzene. The technical sodium salt is a white crystalline solid which decomposes

at 140EC with a bulk density of 30 lb/ft3.

B. Human Health Assessment

1. Toxicology Assessment

The toxicological data base on glyphosate is adequate and will

support reregistration eligibility.

a. Acute Toxicity

The table below summarizes the toxicity results and

categories for technical grade glyphosate. The acute inhalation

study was waived by the Agency since glyphosate technical is a

nonvolatile solid and adequate inhalation studies were conducted on

the end-use product formulations.

Acute Toxicity

Test Result Category

Acute Oral (rat) (1) > 4320 mg/kg III

Acute Dermal (rabbit)(1) > 2 g/kg III

Acute Inhalation (1) Not Required N/A

 1 - MRID 00067039

The following table is derived from MPs considered

toxicologically similar to glyphosate technical.
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Acute Toxicity

Test Result Category

Eye Irritation (1) mild irritation, clears in 7

days

III

Dermal Irritation (2) slight irritation IV

Skin Sensitization (3) negative N/A

 1 - MRID 41400603

 2 - MRID 41400604

 3 - MRIDs 00137137, 00137138, 00137139, 00137140

Other studies submitted to the Agency give similar results.

They are acceptable for reregistration (MRIDs 41400601, and

41400602)

b. Subchronic Toxicity

In a 90-day feeding study Sprague-Dawley rats were fed diets

containing 0, 1000, 5000 or 20000 ppm of glyphosate for three

months. These doses were equivalent to 0, 63, 317 and 1267

mg/kg/day, respectively (males) and 0, 84, 404 and 1623 mg/kg/day,

respectively (females). The following findings were regarded as

possibly treatment-related: (1) increased serum phosphorus and

potassium in all treated groups, males and females; (2) increased

serum glucose in the mid-dose and high-dose males; (3) increased

blood urea nitrogen (BUN) and serum alkaline phosphatase in the

high-dose males; and (4) occurrence of pancreatic lesions in the

high-dose males (pancreas was not examined in the low-dose and

mid-dose groups). Based on these findings, the systemic NOEL is

< 1000 ppm (not determined definitively) for both sexes. (MRIDs

40559401, and 00093879)

In a second 90-day feeding study CD-1 mice were fed diets

containing 0, 250, 500 or 2500 mg/kg/day of glyphosate for three

months. Body weight gains of the high-dose males and females

were about 24% and 18% lower, respectively, than those of the

controls. Body weight gains of the low-dose and mid-dose groups

were comparable to those of the controls. Based on the reduced
GLYPHOSATE RED

September 1993

12

body weight gains in both sexes, the NOEL for systemic toxicity is

500 mg/kg and the LOEL is 2500 mg/kg. (MRID 00036803)

In a 21-day dermal study glyphosate was applied to the skin

of New Zealand white rabbits using 10 rabbits/sex/dose (5 with intact

and 5 with abraded skin). The levels of glyphosate tested were 10,

1000 or 5000 mg/kg/day. The rabbits were exposed for three

consecutive weeks, 6 hours/day, 5 days/week. Treatment-related

effects observed only in the high dose groups included: (1) very

slight erythema and edema in intact and abraded skin of both sexes;

(2) decreased food consumption in males; and (3) decreased

serum lactic dehydrogenase in both sexes. Based on these effects,

the NOEL for males and females is 1000 mg/kg/day and the LOEL

is 5000 mg/kg/day. (MRID 00098460)

The required 90-day feeding study in dogs is satisfied by the

one-year dog feeding study. (MRID 00153374)

c. Chronic Toxicity

A chronic feeding/carcinogenicity study was conducted using

male and female Sprague-Dawley rats which were fed diets

containing 0, 30, 100 or 300 ppm of glyphosate for 26 months.

These levels were equivalent to 0, 3, 10 and 31 mg of

glyphosate/kg/day, respectively, for the males and 0, 3, 11 and 34

mg of glyphosate/kg/day, respectively, for the females. There were

no effects based on any of the parameters examined (toxic signs,

mortality, body weights, food consumption, hematology, clinical

chemistry, urinalysis, organ weights and organ/tissue pathology).

Therefore, the NOEL for systemic toxicity is $ 300 ppm (HDT; males:

31 mg/kg/day and females: 34 mg/kg/day). (MRID 00093879)

A second chronic feeding/carcinogenicity study was

conducted using male and female Sprague-Dawley rats which were

fed diets containing 0, 2000, 8000 or 20000 ppm of glyphosate for

2 years. These levels were equivalent to 0, 89, 362 or 940

mg/kg/day, respectively, for the males and 0, 113, 457 or 1183

mg/kg/day, respectively, for the females. Treatment-related effects

observed only in the high-dose group included: (1) In the females:

decreased body weight gains; and (2) In the males: increased

incidence of cataracts and lens abnormalities, decreased urinary
GLYPHOSATE RED

September 1993

13

pH, increased absolute liver weight and increased liver weight/brain

weight ratio (relative liver weight). No significant systemic effects

were observed in the low-dose and mid-dose male and female

groups. Therefore, the NOEL for systemic toxicity is 8000 ppm

(males: 362 mg/kg/day and females: 457 mg/kg/day) and the LOEL

is 20000 ppm (HDT; males: 940 mg/kg/day and females: 1183

mg/kg/day). (MRID 41643801)

A chronic study was conducted using male and female

beagle dogs which were given glyphosate in gelatin capsules

containing 0, 20, 100 or 500 mg/kg/day for one year. There were no

effects based on all parameters examined, in all groups. Therefore,

the NOEL for systemic toxicity is $ 500 mg/kg/day, for both sexes.

(MRID 00153374)

d. Carcinogenicity

A chronic feeding/carcinogenicity study was conducted using

Sprague-Dawley rats which were fed diets containing glyphosate

(males: 0, 3, 10 or 31 mg/kg/day and females: 0, 3, 11 or 34

mg/kg/day) for 26 months. The following findings were observed in

the high-dose groups when compared with the concurrent controls:

(1) increased incidence of thyroid C-cell carcinomas in females; and

(2) increased incidence of interstitial cell (Leydig cell) testicular

tumors. However, the Agency concluded that these neoplasms were

not treatment-related and glyphosate was not considered to be

carcinogenic in this study because the incidence of thyroid

carcinomas was not statistically significant and the incidence of

testicular tumors was within the historical incidence. The Agency

also concluded that this study was not conducted at high enough

dose levels for an adequate negative carcinogenicity. (MRID

00093879)

A chronic feeding/carcinogenicity study was conducted using

Sprague-Dawley rats fed diets containing glyphosate (males: 0, 89,

362 or 940 mg/kg/day and females: 0, 113, 457 or 1183 mg/kg/day)

for 2 years. The study showed a slightly increased incidence of (1)

pancreatic islet cells adenomas in the low-dose and high-dose

males; (2) hepatocellular (liver) adenomas in the low-dose and highdose males; and (3) thyroid C-cells adenomas in the mid-dose and

high-dose males and females. The Agency concluded that these
GLYPHOSATE RED

September 1993

14

adenomas were not treatment-related and glyphosate was not

considered to be carcinogenic in this study. With respect to

pancreatic islet cells adenomas, there was no statistically significant

positive dose-related trend in their occurrence; there was no

progression to carcinomas; and the incidence of pancreatic

hyperplasia (non-neoplastic lesion) was not dose-related. With

respect to hepatocellular adenomas, the increased incidence of

these neoplasms was not statistically significant in comparison with

the controls; the incidence was within the historical control range;

there was no progression to carcinomas; and the incidence of

hyperplasia was not compound-related. With respect to thyroid Ccell adenomas, there was no statistically significant dose-related

trend in their occurrence; the increased incidence was not

statistically significant; there was no progression to carcinomas; and

there was no significant dose-related increase in severity or

incidence of hyperplasia in either sex. (MRID 41643801)

A carcinogenicity study in mice was conducted with CD-1

mice fed diets containing 0, 150, 750 or 4500 mg/kg/day of

glyphosate for 18 months. No effects were observed in the low-dose

and mid-dose groups. The following findings were observed in the

high-dose group: (1) decreased body weight gain in males and

females; (2) increased incidence of hepatocellular hypertrophy,

hepatocellular necrosis and interstitial nephritis in males; (3)

increased incidence of proximal tubule epithelial basophilia and

hypertrophy in females; and (4) slightly increased incidence of renal

tubular adenomas, a rare tumor, in males. Based on these effects,

the systemic NOEL and LOEL were 750 mg/kg/day and 4500

mg/kg/day, respectively. The Agency concluded that the occurrence

of these adenomas was spontaneous rather than compound-induced

because the incidence of renal tubular adenomas in males was not

statistically significant when compared with the concurrent controls.

An independent group of pathologists and biometricians also

conducted extensive evaluations of these adenomas and reached

the same conclusion. Therefore, glyphosate was not considered to

be carcinogenic in this study. (MRIDs 00130406, and 00150564)

On June 26, 1991, the Agency classified glyphosate in Group

E (evidence of non-carcinogenicity for humans), based on a lack of

convincing evidence of carcinogenicity in adequate studies with two

animal species, rat and mouse.
GLYPHOSATE RED

September 1993

15

e. Developmental Toxicity

A developmental toxicity study was conducted with pregnant

Charles River COBS CD rats which were administered 0, 300, 1000

or 3500 mg/kg/day of glyphosate by gavage during gestation days

6 through 19. Treatment-related effects observed only in the highdose dams included: (1) diarrhea; (2) decreased mean body weight

gain; (3) breathing rattles; (4) inactivity; (5) red matter around the

nose and mouth, and on forelimbs and dorsal head; (6) decreases

in total implantations/dam and inviable fetuses/dam; and (7) deaths

(6/25 or 24% of the group). Treatment-related developmental effects

observed only in the high-dose group included: (1) increased

number of litters and fetuses with unossified sternebrae; and (2)

decreased mean fetal body weights. Therefore, the NOEL and

LOEL for maternal toxicity are 1000 mg/kg/day and 3500 mg/kg/day,

respectively. The NOEL and LOEL for developmental toxicity are

1000 mg/kg/day and 3500 mg/kg/day, respectively. (MRID

00046362)

In a second study, pregnant Dutch Belted rabbits were

administered 0, 75, 175 or 350 mg/kg/day of glyphosate by gavage

during gestation days 6 through 27. Treatment-related findings were

observed only in the high-dose group and included: (1) diarrhea; (2)

nasal discharge; and (3) death (10/16 or 62.5% of does died by

gestation day 21). Developmental toxicity was not observed at any

dose tested. Therefore, the NOEL and LOEL for maternal toxicity

are 175 mg/kg/day and 350 mg/kg/day, respectively. The NOEL for

developmental toxicity is $ 175 mg/kg/day. Due to high maternal

mortality at the 350 mg/kg/day dose level, too few litters (only 6) were

available to assess adequately developmental toxicity at that level.

(MRID 00046363)

f. Reproductive Toxicity

A reproduction study was conducted with male and female

Sprague-Dawley rats which were administered 0, 3, 10 or 30

mg/kg/day of glyphosate continuously in the diet for three successive

generations. The only effect observed was an increased incidence

of focal tubular dilation of the kidney (both unilateral and bilateral

combined) in the high-dose male F3b pups. Therefore, the NOEL for

systemic and reproductive toxicity is $ 30 mg/kg/day (HDT). The
GLYPHOSATE RED

September 1993

16

NOEL and LOEL for developmental toxicity are 10 mg/kg/day and

30 mg/kg/day, respectively. (MRID 00105995)

Another reproduction study was conducted with SpragueDawley rats which were administered 0, 100, 500 or 1500

mg/kg/day of glyphosate continuously in the diet for two successive

generations. Treatment-related effects observed only in the highdose group included: (1) soft stools, very frequent, in the Fo and F1

males and females; (2) decreased food consumption and body

weight gain of the Fo and F1 males and females during the growth

(premating) period; and (3) decreased body weight gain of the F1a,

F2a and F2b male and female pups during the second and third

weeks of lactation. Focal tubular dilation of the kidneys, observed

in the previous study (00105995), was not observed at any dose

level in this study. Based on the above findings, the systemic NOEL

and LOEL are 10000 ppm (500 mg/kg/day) and 30000 ppm (1500

mg/kg/day), respectively. The reproductive NOEL is 30000 ppm

(1500 mg/kg/day; HDT); and the developmental NOEL and LOEL

are 10000 ppm (500 mg/kg/day) and 30000 ppm (1500 mg/kg/day),

respectively. (MRID 41621501)

Since the focal tubular dilation of the kidneys was not

observed at the 1500 mg/kg/day level (HDT) in the 2-generation rat

reproduction study but was observed at the 30 mg/kg/day level

(HDT) in the 3-generation rat reproduction study (00105995), the

Agency concluded that the latter was a spurious rather than

glyphosate-related effect.
GLYPHOSATE RED

September 1993

17

g. Mutagenicity

A Gene mutation assay in an Ames Test was conducted

using glyphosate, both with and without metabolic activation. The

strains of Salmonella typhimurium used were TA98, TA100,

TA1535 and TA1537. No increases in reverse mutations were

observed at any concentration. (MRID 00078620)

A gene mutation assay in mammalian cells was conducted

using glyphosate in the Chinese hamster ovary (CHO)

cells/hypoxanthine - guanine -phosphoribosyl transferase (HGPRT)

assay, with and without metabolic activation. No mutagenic

response was observed either with or without metabolic activation

up to the limit of cytotoxicity (10 mg/Ml). (MRID 00132681)

A Structural Chromosomal Aberration Assay was conducted

using a single dose of glyphosate administered intraperitoneally

(i.p.) to male and female Sprague-Dawley rats. The dose used was

1 g/kg of body weight and the bone marrow cells were examined for

clastogenic (chromosome-damaging) effect. No significant

clastogenic effects were observed. (MRID 00132683)

In a fourth study, glyphosate was tested in two assays: the

rec-assay using B. subtilis H17 (rec+) and M45 (rec-); and the

reverse mutation assays using E. coli WP2 hcr and Salmonella

typhimurium strains TA98, TA100, TA1535, TA1537 and TA1538,

with and without metabolic activation. No increases in mutations

were observed in either study. (MRID 00078619)

h. Metabolism

Two metabolism studies with rats are available. In the first

study, single or repeated doses of radiolabeled 14C-glyphosate were

administered orally to male and female Sprague-Dawley rats.

Following a single oral dose of 14C-glyphosate, 30 to 36% of the

dose was absorbed and less than 0.27% of the dose was eliminated

as CO2. Ninety-seven point five percent of the administered dose

was excreted in the urine and feces as the parent compound,

glyphosate. Amino methyl phosphonic acid (AMPA) was the only

metabolite found in urine (0.2-0.3% of the administered dose) and

feces (0.2-0.4% of the administered dose). Less than 1.0% of the
GLYPHOSATE RED

September 1993

18

absorbed dose remained in tissues and organs, primarily in bone

tissue. Repeated dosing at 10 mg/kg did not significantly change

the metabolism, distribution or excretion of glyphosate. (MRIDs

40767101, and 40767102)

In a second study, male and female Sprague-Dawley rats

received single intraperitoneal injections of radiolabeled 14Cglyphosate. The dose level of glyphosate used for male and female

rats was 1150 mg/kg. Blood samples were collected 0.25, 0.50, 1,

2, 4, 6 and 10 hours after injection. Femoral bone marrow samples

were collected from one third of the male and female rats sacrificed

at 0.5, 4, or 10 hours after injection. Thirty minutes after injection of

glyphosate, the concentration of radioactivity in the bone marrow of

male and female rats was equivalent to 0.0044% and 0.0072%,

respectively, of the administered dose. Assuming first order

kinetics, the decrease in radioactivity in bone marrow occurred with

a half-life of 7.6 and 4.2 hours for males and females, respectively.

Similarly, the half-lives of the radioactivity in plasma were

approximately 1 hour for both sexes. These findings indicate that

very little glyphosate reaches bone marrow, that it is rapidly

eliminated from bone marrow and that it is even more rapidly

eliminated from plasma. (MRID 00132685)

i. Neurotoxicity

The acute and 90-day neurotoxicity screening battery in the

rat (guidelines 81-8-SS, 82-7) is not being required since there was

no evidence of neurotoxicity seen in any of the existing studies at

very high doses and this chemical lacks a leaving group; therefore,

it would not seem likely to inhibit esterases (the presumptive

neurotoxic mechanism of concern for all organophosphates). 
GLYPHOSATE RED

September 1993

19

j. Other Toxicological Endpoints

A dermal penetration study (guideline 85-2) with technical

grade glyphosate is not being required because there are no

toxicological endpoints to indicate this study is necessary.

Domestic Animal Safety Studies (86-1) are not being

required for the use patterns of glyphosate (a plant growth regulator

and herbicide).

Technical grade glyphosate contains N-nitrosoglyphosate

(NNG) as a contaminant. Carcinogenicity testing of nitroso

contaminants is normally required only in those cases in which the

level of nitroso compounds exceeds 1.0 ppm. Analyses showed that

greater than 92% of the individual technical glyphosate samples

contained less than 1.0 ppm NNG. The Agency concluded that the

NNG content of glyphosate was not toxicologically significant. 

 

k. Reference Dose

On August 27, 1992, the Agency's Office of Pesticide

Programs Reference Dose (RfD) Peer Review Committee

recommended that the RfD for glyphosate be established at 2

mg/kg/day. This value was based on the maternal NOEL of 175

mg/kg/day from the rabbit developmental toxicity study (00046363)

and an uncertainty factor (UF) of 100. This RfD has not yet been

confirmed by the Agency RfD Work Group.

In September of 1986, the Joint Food and Agricultural

Organization of the United Nations (FAO)/World Health Organization

(WHO) on Pesticides Residues [JMPR] proposed an Allowable

Daily Intake (ADI) of 0.3 mg/kg body weight for glyphosate per se.

The ADI was based on a 26-month feeding study in the rat yielding

a NOEL of > 31 mg/kg body weight per day and and uncertainty

factor of 100. The Agency places more importance on the

developmental rabbit study since no effect was observed in the 26-

month study whereas maternal mortality was observed in the

developmental rabbit study in the high dose group. JMPR
GLYPHOSATE RED

September 1993

20

acknowledged that there is no effect at the highest dose tested in the

26-month rat study.

2. Exposure Assessment

a. Dietary Exposure

The qualitative nature of the residue in plants is adequately

understood. Studies with a variety of plants including corn, cotton,

soybeans, and wheat indicate that the uptake of glyphosate or its

metabolite, aminomethyl phosphonic acid (AMPA), from soil is

limited. The material which is taken up is readily translocated.

Foliarly applied glyphosate is readily absorbed and translocated

throughout the trees or vines to the fruit of apples, coffee, dwarf citrus

(calamondin), pears and grapes. Metabolism via N-methylation

yields N-methylated glycines and phosphonic acids. For the most

part, the ratio of glyphosate to AMPA is 9 to 1 but can approach 1 to

1 in a few cases (e.g., soybeans and carrots). Much of the residue

data for crops reflects a detectable residue of parent (0.05 - 0.15

ppm) along with residues below the level of detection (<0.05 ppm)

of AMPA. The terminal residue to be regulated in plants is

glyphosate per se.

The qualitative nature of the residue in animals is adequately

understood. Studies with lactating goats and laying hens fed a

mixture of glyphosate and AMPA indicate that the primary route of

elimination was by excretion (urine and feces). These results are

consistent with metabolism studies in rats, rabbits, and cows. The

terminal residues in eggs, milk, and animal tissues are glyphosate

and its metabolite AMPA; there was no evidence of further

metabolism. The terminal residue to be regulated in livestock is

glyphosate per se.

An adequate enforcement method is available for analysis of

residues of glyphosate and its metabolite AMPA in or on plant

commodities and in water. This method utilizes GLC (Method I of

PAM Vol. II; limit of detection is 0.05 ppm). For enforcement of

tolerances in animal commodities, an HPLC method with

fluorescence detection is available; the reported limits of detection

are 0.01 ppm for glyphosate and 0.012 ppm for AMPA.
GLYPHOSATE RED

September 1993

21

The available storage stability data indicate that residues of

glyphosate and its metabolite AMPA are stable under frozen storage

conditions (-20EC): in or on plant commodities for a period of 1

year, in animal commodities for 2 years, and in water for 1 year. No

additional storage stability data are needed. 

All data requirements for magnitude of the residue in plants

have been evaluated and deemed adequate. Additional potato

processing data are being generated. All data requirements for

magnitude of the residue in plants as a result of irrigation with

glyphosate-treated water have also been submitted and are

adequate to support registered use and applicable tolerances. No

additional data are required for magnitude of the residue in animals,

potable water, and fish. A list of residue chemistry study references

is provided on page 24.

b. Occupational and Residential

Occupational and residential exposure can be expected

based on the currently registered uses of products containing

glyphosate. However, due to the low toxicity (acute category III) of

glyphosate and the lack of other toxicological concerns (i.e

carcinogenicity) occupational and residential exposure data are not

required. Glyphosate is a non-selective herbicide applied to

terrestrial food and non-food crops, turf, greenhouse crops, and noncrop areas where total vegetation control is desired. Glyphosate,

when applied at lower rates, is also a plant growth regulator.

Although glyphosate meets the Agency's exposure criteria for

post-application/reentry and/or mixer/loader/applicator exposure

monitoring data, glyphosate does not meet the Agency's toxicity

criteria for these data requirements. Acute oral and dermal toxicity

data for the technical material are in Toxicity Category III and IV. In

addition, glyphosate is poorly absorbed dermally. The acute

inhalation toxicity study for the technical material was waived

because glyphosate is non-volatile and because there were

adequate inhalation studies with end-use products showing low

toxicity. Therefore, occupational and residential exposure data are

not required to support the reregistration of glyphosate. (For these
GLYPHOSATE RED

September 1993

22

same reasons, these data were not required in the 1986

Registration Standard.)

The following information is product-specific related, but is

presented here for informational purposes. Some glyphosate enduse products are in Toxicity Category I and II based on primary eye

irritation or dermal irritation. In California, where physicians are

required to report pesticide poisonings, glyphosate was ranked third

out of the 25 leading causes of illnesses or injury due to pesticides

used between 1980 and 1984. These mixer/loader/applicator

reported incidents consisted of eye and skin irritation. In reports

issued by California since then (1987 and 1988), glyphosate

continued to be a leading cause of illnesses or injuries (primarily eye

and skin irritation). In the 1986 Registration Standard, the Agency

recommended personal protective equipment, including protective

eyewear for mixer/loader/applicators using end-use products that

could cause eye or skin irritation. At that time, it was determined that

mixer/loaders were at risk of eye or skin injury from splashes during

mixing and loading. The Agency did not require personal protective

equipment for users of "homeowner" products (containing up to 10%

glyphosate) because of the low concentration of glyphosate and

because the products are "ready-to-use", requiring no mixing;

therefore, the potential for eye or dermal exposure is minimized.

The Agency, at this time, is not adding any additional

personal protective equipment requirements to the labels of end-use

products; however, any existing personal protective equipment on

those labels must be retained.

The Worker Protection Standard (WPS) for Agricultural

Pesticides -- 40 CFR Parts 156 and 170 -- established an interim

restricted entry interval (REI) of 12 hours for glyphosate because the

acute toxicity categories of glyphosate for acute dermal toxicity, skin

irritation potential, and eye irritation potential are Toxicity Category

III or IV. The Agency has determined that the 12-hour REI for all

WPS sites should be retained as a prudent measure to mitigate risk

to workers entering treated areas after application. Furthermore,

given the known irritation-effects concerns for glyphosate, the

Agency considers the additional protections offered by the

requirements in the WPS essential to its decision that a 12-hour REI

for this chemical will offer sufficient risk mitigation to workers.
GLYPHOSATE RED

September 1993

23

Therefore, during the REI the Agency will allow workers to enter

areas treated with glyphosate during the REI only in the few narrow

exceptions allowed in the WPS.

The Agency has determined that, at this time, the entry

restrictions discussed in this section need not apply to uses of

glyphosate ouside the scope of the Worker Protection Standard for

Agricultural Chemicals, including out-of-scope commercial uses and

homeowner uses. The predicted frequency, duration, and degree of

exposure due to post-application as the result of such uses should

not warrant the risk mitigation measures being required for persons

engaged in the production of agricultural plants for commercial or

research purposes.

3. Risk Assessment

a. Dietary

The chronic dietary risk analysis used tolerance level

residues and assumed all acreage, of the crops considered, was

treated with glyphosate to estimate the Theoretical Maximum

Residue Contribution (TMRC) for the overall U.S. population and 22

population subgroups. These exposures (TMRCs) were then

compared to the RfD for glyphosate to estimate chronic dietary risk.

The calculated TMRC for the overall U.S. population from

food uses of glyphosate is 0.025 mg/kg bwt/day, which represents

1.2% of the RfD. The subgroup most highly exposed, non-nursing

infants less than one year old, has a TMRC of 0.058 mg/kg bwt/day,

or 2.9% of the RfD. Over one third of the dietary exposure and risk

from glyphosate is due to the proposed tolerances on wheat.

This analysis was meant to be a "worst case" scenario of

risk. The inclusion of recommended tolerances for reregistration as

well as tolerances recommended for revocation; the use of the

highest existing, pending, or recommended residue value for each

commodity; and the assumptions of tolerance level residues and

treatment of 100 percent of the crops for every commodity

considered result in an overestimation of exposure and risk values

for glyphosate (though there is some underestimation due to the lack

of consumption information for some of the commodities to which
GLYPHOSATE RED

September 1993

24

glyphosate is expected to be applied). Nonetheless, given the risk

values arrived at by this analysis, EPA concludes that the chronic

dietary risk posed by this pesticide on these food uses is minimal.

b. Occupational and Residential

As discussed above in the occupational exposure

assessment, exposure to humans from proper application of

glyphosate to terrestrial food and non-food crops as well as

greenhouses, turf, and non-crop areas can result in injury (primarily

eye and skin irritation) from splashes during mixing and loading. The

Agency continues to recommend protective clothing (including

protective eye wear) for mixer/loader/applicators using end-use

products that may be in toxicity category I or II for primary eye and

dermal irritation.

c. Dietary Exposure References 

This table references the residue data used to support the

reregistration of glyphosate and includes the commodities eligible

for reregistration.

 Guideline/Commodity References 1

§171-4 (a): Plant Metabolism 00038771, 00039141, 00051983, 00065753, 00108097,

00108129, 00108133, 00108140, 00108151, 00111945

§171-4 (b): Animal Metabolism 00094971, 00108098, 00108099, 00108100, 00108101,

00108116, 00108099, 00108200, 40541301-40541304

§171-4 (c) and (d): Residue Analytical Methods 00028853, 00036222, 00036223, 00036231, 00037688,

00038770, 00038979, 00044423, 00051982, 00053002,

00053005, 00060108, 00061559, 00063714, 00065751,

00065752, 00067425, 00076805, 00078823, 00078824,

00108133, 00108144, 00108149, 00108151, 00108175,

00108176, 00108186, 00108231, 00111945, 00111949,

00122715, 00159419, 00164729, 40502601, 40541304

§171-4 (e): Storage Stability 00039142, 00040083, 00051980, 00053002, 00061553,

00061555, 00108129, 00108132, 40502605, 40532004,

41940701
GLYPHOSATE RED

September 1993

 Guideline/Commodity References 1

25

§171-4 (k) (l): Magnitude of the Residue in Plants

Root and Tuber Vegetables Group

 - Artichokes, Jerusalem N/A

 - Beets, garden 00108159

 - Carrots 00108159

 - Chicory N/A

 - Horseradish N/A

 - Parsnips N/A

 - Potatoes 00108151, 41947001

 

 - Radish 00108159

 - Rutabagas N/A

 - Salsify N/A

 - Sugar beets 00039381, 00108151

 

 - Sweet potato 00108151

 - Turnips 40835201

Leaves of Root and Tuber

 Vegetables Group

 - Beets, greens N/A

 - Chicory leaves N/A

 - Sugar beet tops 00039381, 00108151

 - Turnip tops 40835201

Bulb Vegetables Group

 - Garlic N/A

 - Onions (green and dry bulb) 40783101

Leafy Vegetables (except Brassica)

 Group

 - Celery N/A

 - Lettuce (head and leaf) 00108159

 - Spinach N/A
GLYPHOSATE RED

September 1993

 Guideline/Commodity References 1

26

Brassica Leafy Vegetables Group

 - Broccoli 40802801, 40802801

 - Cabbage 00108159

 - Cauliflower N/A

 - Kale N/A

 - Mustard greens 40802801, 40802801

Legume Vegetables

 (Succulent/Dried) Group

 - Beans (succulent and dried) 00108159

 - Lentils 00108159

 - Peas (succulent and dried) 00108159

 - Soybeans 00015759, 00015760, 00015761, 00015762, 00015763,

00015764, 00015765, 00015766, 00015767, 00024503,

00033954, 00038908, 00040084, 00061555, 00108153,

00108203

 (processed commodities) 00061555, 00108153, 00156793

Foliage of Legume Vegetables

 (Succulent/Dried) Group

 - Bean vines and hay 00108159

 - Lentil forage and hay 00108159

 - Pea vines and straw

 - Soybean forage and hay 00015759, 00015760, 00015761, 00015762, 00015763,

00015764, 00015765, 00015766, 00015767, 00033954,

00038908, 00040084, 00061555, 00108153, 00108203

Fruiting Vegetables Group

Cucurbit Vegetables Group

Citrus Fruits Group 00039142

 (processed commodities) 40159401

Pome Fruits Group 00108129

Stone Fruits Group 00111949
GLYPHOSATE RED

September 1993

 Guideline/Commodity References 1

27

 - Plums (fresh prunes) 00111949

 

Small Fruits and Berries Group

 - Blackberries

 - Blueberries

 - Cranberries 00053002

 - Grapes 00038770, 00108132

 (processed commodities) 40785303

 - Raspberries

Tree Nuts Group 00111945

 - Almond hulls 00111945

Cereal Grains Group

 - Barley 00038908, 00040087, 00044422, 00108203

 (processed commodities) N/A

 - Corn (field and fresh) 00023336, 00023512, 00037687, 00038908, 00040085,

00048284, 00108203, 40502602

 (processed commodities) 40502604, 41478101

 - Oats 00038908, 00040087, 00044422, 00108203

 (processed commodities) N/A

 - Rice 00038908, 00040087, 00044422

 (processed commodities) N/A

 - Rye N/A

 (processed commodities) N/A

 - Sorghum 00038908, 00040087, 00044422, 00108203, 00109271,

40502601

 (processed commodities) 40502603

 - Wheat 00038908, 00040086, 00044426, 00108203, 00122715,

41484301

 (processed commodities) 00150835

Forage, Fodder, and Straw of Cereal Grains Group

 - Barley forage, hay, and straw 00038908, 00040087, 00044422, 00108203
GLYPHOSATE RED

September 1993

 Guideline/Commodity References 1

28

 - Corn forage and fodder 00023336, 00023512, 00037687, 00038908, 00040085,

00048284, 00108203, 40502602

 - Oat forage, hay, and straw 00038908, 00040087, 00044422, 00108203

 - Rice straw 00038908, 00040087, 00044422

 - Rye forage and straw N/A

 - Sorghum forage and fodder 00038908, 00040087, 00044422, 00108203, 00109271,

40502601

 - Wheat forage and straw 00038908, 00040086, 00044426, 00108203, 00122715

Grass Forage, Fodder, and Hay

 Group

00076805, 00108147

Non-grass Animal Feeds (forage,

 fodder, straw, and hay) Group

00076805, 00108147

 - Alfalfa seed 40541304

Miscellaneous Commodities

 - Acerola

 - Atemoya

 - Asparagus 00108144, 40642401

 - Avocados 00108149

 - Bananas 00108175

 - Breadfruit 40149401

 - Canistel 40149401

 - Carambola

 - Cherimoya

 - Cocoa beans

 - Coconut

 - Coffee beans 00051980, 00051981

 - Cotton 00060103, 00061553, 00108176, 00108153, 00108203

 (processed commodities) 00061553, 00108176, 00108153

 - Dates 40149401

 - Figs

 - Genip

 - Guavas 00059050

 - Jaboticaba 40149401

 - Jackfruit 40149401
GLYPHOSATE RED

September 1993

 Guideline/Commodity References 1

29

 - Kiwi fruit

 - Litchi Nut (Lychee)

 - Longan

 - Mamey Sapote

 (Mammee Apple)

 - Mangoes 40580401

 - Okra N/A

 - Olives 00108175, 42398401

 (processed commodities) 00108175, 42398401

 - Palm oil

 - Papayas 00063713

 - Passion Fruit

 - Peanuts 00144341, 00028852

 (processed commodities) 00144341, 00028852

 - Persimmons 40149401

 - Pineapple N/A

 - Pistachio 00111945

 - Sapodilla

 - Sapote (black and white) 40149401

 - Soursop 40149401

 - Sugar apple

 - Sugarcane 00108140

 (processed commodities) 00108168

 - Tamarind 40149401

 - Tea 00078823, 00078824

 - Watercress N/A

§171-4 (h): Magnitude of the

 Residue in Plants Resulting from

 the Use of Irrigation Water

00039381, 40541305

§171-4 (j): Magnitude of the Residue in Meat, Milk, Poultry,

 and Eggs

00108115, 40532001-03

§171-4 (g): Magnitude of the

 Residue in Fish

00036229, 00076491, 00154311, 00155120
GLYPHOSATE RED

September 1993

 Guideline/Commodity References 1

30

§171-4 (f): Nature and Magnitude

 the Residue in Drinking and

 Irrigation Water

00039377, 00039381, 00077227, 00077228, 00077229,

00077230, 00077231, 00077232, 00077233, 00077234,

00077235, 00077236, 00077237, 00077238, 00077301,

00108173, 

§171-4 (i): Magnitude of the 

 Residue in Food Handling

 Establishment

§171-5: Reduction of Residues

1 N/A means not available by MRID number. Those guidelines/commodities which do not list a MRID reference

number, additional reference information can be provided from Table A in the Product and Residue Chemistry

Chapters by R.B. Perfetti, Chemistry Branch Reregistration Support (CBRS# 10665) in the Health Effects Division

dated 10/27/92 through FOI.

C. Environmental Assessment

1. Environmental Fate 

a. Environmental Fate and Transport

(1) Hydrolysis 

Glyphosate is stable at pH 3, 6, 9 at 5 and 35EC.

(Accession 00108192)

(2) Photodegradation in Water 

Glyphosate is stable to photodegradation in pH 5, 7,

and 9 buffered solutions under natural sunlight. (MRID

41689101)

(3) Photodegradation on Soil 

Glyphosate is stable to photodegradation on soil.

(MRID 41335101)

(4) Aerobic Soil Metabolism 
GLYPHOSATE RED

September 1993

31

Data indicate half-life values of 1.85 and 2.06 days in

Kickapoo sandy loam and Dupo silt loam respectively.

Aminomethyl phosphonic acid (AMPA) was the major

degradate. (MRID 42372501)

(5) Anaerobic Aquatic Metabolism 

Glyphosate has a half-life of 8.1 days in anaerobic

(flooded plus nitrogen atmosphere) silty clay loam sediment.

AMPA was the major degradate. (MRID 42372502)

(6) Aerobic Aquatic Metabolism 

Glyphosate has a half-life of 7 days in flooded silty clay

loam sediment that was incubated in the dark at 24.6 ± 0.57

C for 30 days. AMPA was the major degradate. (MRID

42372503)

(7) Leaching/Adsorption/Desorption 

Kd values of 62, 90, 70, 22, and 175 were reported for

Drummer silty clay loam, Ray silt, Spinks sandy loam,

Lintonia sandy loam, and Cattail Swamp sediment

respectively. After (aged) leaching 7 soils with 20" of water,

the recovered radioactivity in the soils was 93-100% of the

applied material. (Accessions 00108192, 00076493,

00108140)

(8) Terrestrial Field Dissipation

The Agency has received an interim report on a

terrestrial field dissipation study in progress by Monsanto

Company. (MRID 42607501) 

This report contains data from eight different field

sites. Some of the data from the individual field sites are

deficient; however, the Agency may use the data from the

eight field sites together to satisfy the terrestrial field

dissipation 164-1 data requirement.
GLYPHOSATE RED

September 1993

32

The interim report results from the first 12 months of

bareground field dissipation trials from eight sites show that

the median half-life (DT50) for glyphosate applied at maximum

annual use rates (7.95 lb a.e./acre, 10.7 lb a.i./acre) was 13.9

days with a range of 2.6 (Texas) to 140.6 (Iowa) days.

Acceptable aerobic soil, aerobic aquatic and anaerobic

aquatic metabolism studies demonstrate that under those

conditions at 25EC in the laboratory glyphosate degrades

rapidly with half-lives of approximately 2, 7 and 8 days

respectively. The reported half-lives (DT50) from the field

studies conducted in the coldest climates, ie. Minnesota, New

York and Iowa, were the longest at 28.7, 127.8, and 140.6

days respectively indicating that glyphosate residues in the

field are somewhat more persistent in cooler climates as

opposed to milder ones (Georgia, California, Arizona, Ohio,

and Texas).

 

Glyphosate (as well as AMPA) was shown to remain

predominantly in the 0-6 inch soil layer throughout the

duration of the study at all field sites. Iowa was the individual

test site to have average glyphosate residues, at all sampling

times, greater than 0.01 ppm in the 6-12 inch depth. There

were a number of detections from 0.01 to 0.09 ppm in the 6-

12 inch layer in Minnesota, New York and Texas, and

glyphosate was detected at generally <0.05 ppm at the other

5 field sites (6-12 inch depth). 

Glyphosate was detected at three different sites below

12 inches. In California, at 0 DAT, average glyphosate

residues were 0.21 ppm and 0.10 ppm in the 12-18 and 18-

24 inch soil horizons respectively. Soil core contamination

was attributed to these detections since movement of

residues to this depth on the first day of sampling is unlikely.

 In Arizona at 21 DAT the average glyphosate residues were

0.06, in the 18-24 inch soil layer. There were no glyphosate

residues in the 6-12 or 12-18 inch soil layer in Arizona on 21

DAT and in subsequent samples below 12 inches which may

indicate a problem with sampling technique. In Iowa at 190

DAT the average glyphosate residues were 0.05 ppm in the

12-18 inch soil layer. Since there were no glyphosate

residues detected in the 6-12 inch soil layer at 190 DAT, and
GLYPHOSATE RED

September 1993

33

the lack of a significant amount of rainfall between sampling

intervals in combination with the amount of time between

sampling intervals and the high adsorptive characteristics of

glyphosate give an indication that there may have been a

problem with sampling technique.

AMPA was also shown to remain predominantly in the

0-6 inch soil layer. AMPA was found at every test site on Day

0 samples indicating the rapid degradation of parent

glyphosate. The AMPA levels generally reached a maximum

between day 14 and day 30. Where the field half-lives were

longer (Iowa, Minnesota, New York), the maximum average

AMPA levels occurred between 62 and 95 DAT. The

maximum average AMPA levels found in the 0-6 inch soil

layer were 0.6 ppm and occurred in Ohio and Georgia at 21

DAT and 61 DAT respectively. The AMPA levels at those

sites had decreased to 0.12 and 0.44 ppm at 12 months after

treatment. 

In all samples but three, AMPA residue levels were

<0.05 ppm in the 6-12 inch soil layer. In New York at 14 and

30 DAT average residues were detected at 0.06 ppm. In

Iowa at the 92 DAT sample average AMPA residues were

0.08 ppm. Iowa and New York also exhibited 50%

dissipation times of 140.6 and 127.8 days respectively. 

AMPA levels were detected at 0.06 ppm in the 18-24

inch soil layer on 21 DAT in Arizona and 0.04 and 0.03 ppm

in the 12-18 inch soil layer at 90 and 180 DAT respectively in

New York.

A final report on the terrestrial field dissipation study

showed the median half-life (DT50) (of eight sites) of AMPA

was 240 days with a range of 119 (Ohio) to 958 (California)

days. The half-lives for the dissipation of AMPA for seven of

the eight test sites were:

! Arizona 142 days

! California 958 days

! Georgia 896 days

! Minnesota 302 days
GLYPHOSATE RED

September 1993

34

! New York 240 days

! Ohio 119 days

! Texas 131 days

Iowa was not calculated because recharging of AMPA

residues was greater than degradation. AMPA was shown

to remain predominantly in the 0-6 inch soil layer throughout

the duration of the study at all eight field sites. AMPA was

detected three times (at a concentration greater than 0.05

ppm) at depths greater than 12 inches. The three detections

were attributed to contamination during sampling rather than

vertical mobility. 

(9) Aquatic Field Dissipation 

Glyphosate dissipated from water (irrigation source)

with a calculated half-life of 7.5 days and 120 days from the

sediment of the farm pond in Missouri. (MRID 40881601)

In Michigan, Georgia and Oregon pond and stream

water, the maximum glyphosate concentrations were

measured immediately posttreatment and dissipated rapidly.

Glyphosate accumulated in the pond sediment, and to a

lesser extent in the stream sediments; glyphosate was

present in pond sediment at $1 ppm in Michigan and Oregon

at approximately 1 year posttreatment. (MRID 41552801)

(10) Forestry Dissipation

When aerially applied at 3.75 lb/A to forested sites in

Michigan, Oregon, and Georgia, glyphosate averaged 652-

1273 ppm in tree foliage immediately posttreatment. It then

declined rapidly with half-lives of <1 day at the Michigan and

Georgia sites and <14 days at the Oregon site.

The forestry dissipation study results demonstrate that

when used under normal silviculture practices according to

label directions, the maximum combined glyphosate and

AMPA residue level in soil is less than 5 ppm. Glyphosate

and AMPA residues in soil dissipate with time. The average

half-life for the dissipation of glyphosate was 100 days, and
GLYPHOSATE RED

September 1993

35

ranged from 35 to 158 days. The average half-life for the

dissipation of AMPA was 118 days, and ranged from 71

days to 165 days. (MRID 41552801)

(11) Accumulation in Confined Rotational Crops

Glyphosate residues (expressed as fresh weight)

accumulated in lettuce, carrots, and barley planted 30, 119,

and 364 days after sandy loam soil was treated with

glyphosate at 3.71 lb ai/A. Accumulation decreased as the

length of the rotation increased. In crops planted at 30 days,

posttreatment, [14C]residues at harvest were 0.097 ppm in

lettuce, 0.051 and 0.037 ppm in carrot tops and roots,

respectively, and 0.188 and 0.175 ppm in barley grain and

straw, respectively. In immature lettuce harvested at 40 and

60 days postplanting, [14C]residues were 0.108 and 0.048

ppm, respectively. In crops planted at 119 days

posttreatment, [14C]residues at harvest were 0.037 ppm in

lettuce, 0.028 and 0.017 ppm in carrot tops and roots,

respectively, and 0.078 and 0.056 ppm in barley grain and

straw, respectively. In immature lettuce harvested at 28 and

48 days postplanting, [14C]residues were 0.059 and 0.055

ppm, respectively. In crops planted at 364 days

posttreatment, [14C]residues at harvest were 0.028 ppm in

lettuce, 0.018 and 0.0096 ppm in carrot tops and roots,

respectively, and 0.047 and 0.061 ppm in barley grain and

straw, respectively. In immature lettuce harvested at 35 and

61 days postplanting, [14C]residues were 0.057 and 0.043

ppm, respectively; in barley forage harvested at 48 days

postplanting, [14C]residues were 0.056 ppm. (MRID

41543201 and 41543202)

(12) Accumulation in Irrigated Crops

Alfalfa, corn (grain and forage), grass (fescue or

sudan) and lettuce were irrigated five to eight times during

the 1987 growing season with glyphosate treated water

containing a maximum of 21.3 ppm (on treatment day then fell

to 0.46 ppm by 1 day after treatment) of glyphosate.

Residues in the sediment beneath the treated water reached

a maximum of 3.5 ppm at 14 days after treatment. Residues
GLYPHOSATE RED

September 1993

36

of glyphosate in the sprinkler water at the pond site were the

highest 7 days after treatment at 0.12 ppm. One lettuce

sample from the Missouri location (the pond site) at 29 days

after treatment (of water source) and 5 irrigation events was

found to contain 0.06 ppm glyphosate. (MRID 40541305)

(13) Bioaccumulation in Fish 

Maximum bioconcentration factors were 0.38X for

edible tissues, 0.63X for nonedible tissues, and 0.52X for

whole fish. (MRID 41228301)
GLYPHOSATE RED

September 1993

37

(14) Laboratory and Field Volatility

The requirement of these studies was waived based

on the low vapor pressure of glyphosate.

b. Environmental Fate and Groundwater Assessment

In general, the available field and laboratory data indicate

glyphosate adsorbs strongly to soil and would not be expected to

move vertically below the 6 inch soil layer. Based on unaged batch

equilibrium studies glyphosate and glyphosate residues are

expected to be immobile with Kd(ads) values ranging from 62 to 175.

The mechanism of adsorption is unclear; however, it is speculated

that it may be associated with vacant phosphate sorption sites or

high levels of metallic soil cations. The data indicate that chemical

and photochemical decomposition is not a significant pathway of

degradation of glyphosate in soil and water. However, glyphosate

is readily degraded by soil microbes to aminomethyl phosphonic

acid (AMPA), which is degraded to CO2, although at a slower rate

than parent glyphosate. Even though glyphosate is highly water

soluble it appears that parent glyphosate and AMPA have a low

potential to move to ground-water due to their strong adsorptive

characteristics demonstrated in the laboratory and field studies.

However, glyphosate does have the potential to contaminate surface

waters due to its aquatic use patterns and erosion via transport of

residues adsorbed to soil particles suspended in runoff water. If

glyphosate were to reach surface water it would be resistant to

hydrolysis and aqueous photolysis.

Based on the low vapor pressure of glyphosate, volatilization

from soils will not be an important dissipation mechanism. The low

octanol/water coefficient suggests that glyphosate will have a low

tendency to accumulate in fish.

2. Ecological Effects

a. Ecological Hazard
GLYPHOSATE RED

September 1993

38

(1) Effects to Nontarget Birds

 To establish the toxicity of glyphosate to birds, tests

were required using the technical grade material.

(a) Avian Single-Dose Oral LD50 - Technical 

Acute Oral Toxicity Findings

Species % AI LD50 (95% CL) Conclusions

Bobwhite

quail

83% > 2000 mg/kg practically non-toxic to upland game birds

One avian single-dose oral study on either a waterfowl species (preferably mallard duck) or an upland

species (preferably bobwhite quail) was required. These data indicate that technical glyphosate is

practically non-toxic to an upland bird species on an acute oral basis. The guideline requirement for an

avian acute oral study is fulfilled. (Study ID 234395)

(b) Avian Dietary - Technical

Avian Subacute Dietary Toxicity Findings

Species % AI Reproductive

Impairment

Conclusions

Mallard duck 98.5%

Tech

> 4640 ppm no more than slightly toxic to upland game birds and

waterfowl

Bobwhite

quail

98.% Tech > 4640 ppm

Two subacute dietary studies, one study on a species of waterfowl (preferably mallard duck) and one on

an upland game bird species (preferably a bobwhite quail), were required. These data indicate that the

technical glyphosate is no more than slightly toxic to birds on a dietary basis. The guideline requirement

is fulfilled for both studies. (Study IDs 94171 and 00086492)
GLYPHOSATE RED

September 1993

39

(c) Avian Reproduction

Avian Reproduction Findings

Species % AI Reproductive

Impairment

Conclusions

Mallard duck 83% 

Tech

No effects up to 1000

ppm

not expected to cause reproductive impairment

Mallard duck 90.4% 

Tech

No effects up to 30

ppm

Bobwhite

quail

83%

Tech

No effects up to 1000

ppm

An avian reproduction test was required to support registration of the end-use products of glyphosate

since the following guideline criteria have been exceeded. The labeling for several use patterns contains

directions for use under which birds may be subject to repeated exposure to glyphosate. The labeling

allows repeat application for certain uses, such as alfalfa, barley, oats, apples, cherries, and oranges.

These data indicate that technical glyphosate is not expected to cause reproductive impairment. The

guideline requirements for an avian reproduction study on both upland game bird and waterfowl are

fulfilled. (Study IDs 235924, 00036328, and 235924)

(d) Summary of Findings

Glyphosate is practically non-toxic to bobwhite

quail on the basis of acute oral toxicity. An LD50

greater than 2000 mg/kg was determined for

bobwhite quail given a single oral dose of technical

glyphosate. Studies indicate that the 8-day dietary

LC50 of the chemical is greater than 4000 ppm for

both mallard ducks and bobwhite quail. These data

indicate that the chemical is slightly toxic to birds.

Avian reproduction studies indicate reproductive

impairment would not be expected at a dietary level of

up to 1000 ppm. The available acute toxicity data do

not indicate a requirement of precautionary labeling

for birds on products containing glyphosate.
GLYPHOSATE RED

September 1993

40

(2) Effects on Non-Target Fish

(a) Acute Toxicity to Freshwater Fish

Acute Toxicity to Freshwater Fish Findings

Species % AI 48-hr LC50

(95%CL)

Conclusions

Bluegill sunfish 96.5% > 24 mg/l ranges in toxicity from slightly non-toxic to practically non-toxic

to both cold water and warm water fish

Fathead

Minnow

87.3% 84.9 mg/l

(72.9-99.3) 

Bluegill sunfish 83% 120 mg/l (111-

130)

Rainbow Trout 83% 86 mg/l (70-

106)

Rainbow Trout 96.7% 140 mg/l (120-

170)

Fathead

minnow

96.7% 97 mg/l (79-

120)

Channel catfish 96.7% 130 mg/l (110-

160)

Bluegill sunfish 96.7% 140 mg/l (110-

160)

The minimum data required for establishing the acute toxicity of glyphosate to freshwater fish are the

results of two 96-hour studies with the technical grade product. One study was to be performed on a cold

water fish species (preferably rainbow trout) and one study was to be performed using a warm water

species (preferably bluegill sunfish). The results of these eight studies indicate that technical glyphosate

is slightly to practically nontoxic to both cold water and warm water fish. The guidelines requirement

for acute toxicity testing of the technical on freshwater fish is fulfilled. (Study IDs 00108112, 00108171,

234395, 097661, and 249160) 
GLYPHOSATE RED

September 1993

41

(b) Chronic Toxicity to Freshwater Fish

Chronic Toxicity to Freshwater Fish Findings

Species % AI Results Conclusions

Fathead

Minnow

87.3%

tech

MATC > 25.7 mg/l no effects at or below this level

Due to the aquatic use of the chemical, its presence in water is likely to be continuous or recurrent

regardless of toxicity; therefore, chronic testing was required. This fish full life cycle study satisfies

the generic guideline requirement for chronic freshwater fish testing. (Study ID 00108171)

Acute Toxicity to Freshwater Fish

Findings from Studies using Formulated Products

Species % AI

(IPA salt)

96-hr LC50

(95% CL)

Conclusions

Bluegill

sunfish

41.8% 5.8 mg/l (4.4-8.3) ranges in toxicity from moderately toxic to practically nontoxic to both warmwater and coldwater fish

Rainbow

Trout

41.8% 8.2 mg/l (6.4-9.0)

Channel

catfish

41.36% 16 mg/l (9.4-26)

Rainbow

Trout

41.36 11 mg/l (8.7-14)

Bluegill

sunfish

41.36% 14 mg/l (8.7-24)

Fathead

Minnow

41.36% 9.4 mg/l (5.6-16)

Rainbow

Trout

62.4% >1000 mg/l

Bluegill

sunfish

62.4% >1000 mg/l

Rainbow

Trout

*41.2% +

15.3 "AA"

surfactant

120 mg/l (56-180)
GLYPHOSATE RED

September 1993

Acute Toxicity to Freshwater Fish

Findings from Studies using Formulated Products

42

Rainbow

Trout

*40.7% +

15% "W"

surfactant

150 mg/l (100-

320)

Bluegill

sunfish

*40.7% +

15% "W"

surfactant

>100 mg/l

Bluegill

sunfish

*41.2% +

15.3%

"AA"

surfactant

>180 mg/l

Rainbow

Trout

7.03% +

0.5% "X77"

240 mg/l (180-320

mg/l)

Bluegill

sunfish

7.03%+

0.5% "X77"

830 mg/l (620-

1600)

Rainbow

Trout

51% 8.3 mg/l (7.0-9.9)

Fathead

minnows

41% 2.3 mg/l (1.9-2.8)

Rainbow

Trout

41% 9.0 mg/l (7.5-11)

Bluegill

sunfish

41% 4.3 mg/l (3.4-5.5)

Channel

catfish

41% 13 mg/l (11-16)

Bluegill

sunfish

41% 5 mg/l (3.8-6.6)

Rainbow

Trout

41% 1.3 mg/l (1.1-16)

Testing of an end-use product is required if the pesticide will be introduced directly into an aquatic

environment when used as directed by the label. Drainage systems would be included in such a category.

Therefore, formulated product testing was required. According to the surfactant selected, the formulated

product toxicity ranges from moderately toxic to practically non-toxic. (Study ID 249159, 00070894,
GLYPHOSATE RED

September 1993

43

00070895, 00070897, 00070896, 00078661, 00078662, 00078658, 00078655, 00078656, 00078659,

00078664, 00078665, 249160)

Surfactant Test Findings

Species % AI 96-hour LC50

(95% CL)

Conclusions

Fathead

minnow

MONO818

Tech 100%

1.0 mg/l (1.2-

1.7)

ranges in toxicity from highly toxic to slightly toxic to warmwater

and coldwater fish

Rainbow

trout

MONO818

Tech 100%

2.0 mg/l (1.5-

2.7)

Rainbow

Trout

MONO818 0.65 mg/l (.54-

.78)

Channel

Catfish

MONO8l8

Tech 100%

13 mg/l (10-17)

Bluegill

sunfish

MONO8l8

Tech 100%

3.0 (2.5-3.7)

Bluegill

sunfish

MONO818

Tech 100%

1 mg/l (.72-1.4)

Testing of the surfactant may be required under unusual circumstances. When inerts are likely to be

toxic, testing can be required. These data indicate that MONO818 ranges from moderately toxic to very

highly toxic to both cold and warm water fish after 96 hour exposure. (Study ID 249160) 

(c) Summary of Findings

Three tests on warm water species, one

bluegill and two with fathead minnow, produced the

96-hour LC50s of 120 ppm, 84.9 ppm, and 97 ppm,

respectively (McAllister and Forbis 1978, ID #234395;

EG & G Bionomics 1975, ID #00108171 and Folmar,

Sanders, and Julin 1979, ID #249160). Two rainbow

trout 96-hour LC50s provided values of 86 ppm and

140 ppm. Based on these tests, technical glyphosate

ranges from slightly to practically non-toxic to

freshwater fish species.

Surfactant testing was performed with both

cold water and warm water fish. In this case, the initial

formulation demonstrated an application rate much
GLYPHOSATE RED

September 1993

44

lower than technical glyphosate. The LC50 for rainbow

trout was 1.3 mg/l or moderately toxic. The surfactant

(MON0818) when tested alone produced an LC5 0

value of 0.65 mg/l for rainbow trout indicating a highly

toxic category (Folmar et al. 1979, ID #249160). In

contrast, the formulation of 41.2 percent

isopropylamine salt and 15.3 percent "AA" surfactant

provided a rainbow trout LC50 of 120 mg/l, indicating

a practically non-toxic compound (Thompson and

Griffen 1980, ID #00078658). Bluegill are in the same

category of toxicity with an even higher LC50 of greater

than 180 mg/l (Thompson and Griffen 1980, ID

#00078659). The bluegill and rainbow trout were

similar in sensitivity to the formulation containing the

"W" surfactant with LC50 values of 150 and >100 mg/l,

respectively. Also, neither rainbow trout (LC50 240

mg/l) nor bluegill (LC50 830 mg/l) were very sensitive

to the x-77(.5) surfactant and glyphosate(7.03%). 

The surfactant MON0818 has been tested

separately, producing an LC50 of 13 mg/l on

Chironomous indicating it is a slightly toxic material.

For fish, the catfish appears to be the most tolerant

with an LC50 value of 13 mg/l, and rainbow trout the

most sensitive with an LC50 value of 0.65 mg/l. Based

upon available data products containing MONO8l8

must include the statement, "This pesticide is toxic to

fish."
GLYPHOSATE RED

September 1993

45

(3) Effects on Aquatic Invertebrates

(a) Acute Toxicity to Freshwater Invertebrates

Acute Toxicity to Freshwater Invertebrates Findings

Species % AI 48-hr LC50 (ppm) Conclusions

Daphnia magna 83% tech 780 ranges in toxicity from slightly toxic to

practically non-toxic to freshwater invertebrates

Chironomus

plumosus

96.7%

tech

55 (31-97) 

The minimum data requirement to establish the acute toxicity of glyphosate to freshwater invertebrates

is a 48-hour acute study using the technical material. Test organisms should be first instar Daphnia

magna or early instar amphipods, stone flies or mayflies. The results of these studies indicate that

technical glyphosate is slightly toxic to Chironomus plumosus and is practically non toxic to Daphnia

magna. The guideline requirement for acute testing on a freshwater invertebrate has been fulfilled.

(Study ID 00108172, and 249160)

(b) Chronic Toxicity to Freshwater Invertebrates

Chronic Toxicity to Freshwater Invertebrates Findings

Species % AI Results Conclusions

Daphnia magna 99.7%

tech

MATC > 50 -<

96 mg/L 

caused reduced reproductive capacity

Due to the aquatic use of the chemical its presence in water is likely to be continuous or recurrent

regardless of toxicity; therefore, chronic testing was required. This study satisfies the guideline

requirement for chronic freshwater invertebrate testing. (Study ID 249160) 

Acute Toxicity to Freshwater Invertebrates

Findings from Studies using Formulated Products

Species % AI

(IPA salt)

48-hr LC50

(ppm)

Conclusions

Daphnia magna 62.4% 869 (703-

1019)

ranges in toxicity from moderately toxic to practically non-toxic

to freshwater invertebrates
GLYPHOSATE RED

September 1993

Acute Toxicity to Freshwater Invertebrates

Findings from Studies using Formulated Products

46

Daphnia magna 7.03% +

X-77

surfactant

@0.5%

>1000

Daphnia magna 41.2% +

"AA"

surfactant

@ 15.3%

310 (250-

400)

Daphnia magna 40.7%

MON2139

+ 15%

"W"

surfactant

72 (62-83)

Daphnia magna 41% 3 (2.6-3.4)

Gammarus

pseudolimnaeus

41% 62 (40-98)

Chironomus

plumosus

41% 18 (9.4-32)

Daphnia pulex 51% MON

2139

242(224-

261.5)

Daphnia magna 41.36% 5.3 (4.4-6.3)

Gammarus

pseudolimnaeus

41.83% 41.9 (30.7-

62)

Other

results

Ephemerella

walkeri

41% Mayfly

nymphs

avoided

glyphosate

at

concentratio

ns of 10

mg/L but

not at 1.0

mg/l.
GLYPHOSATE RED

September 1993

Acute Toxicity to Freshwater Invertebrates

Findings from Studies using Formulated Products

47

Chironomus

plumosus

41% Significant

increases in

stream drift

of midge

larvae was

observed

after the 2.0

mg/l, but

not at the

0.02 or 0.2

mg/l level.

Testing of an end-use product is required if the pesticide will be introduced directly into an aquatic

environment when used as directed by the label. Drainage systems (wet and dry) would be included in

such a category. Therefore, formulated product testing was required. According to the surfactant

selected, the formulated product toxicity ranges from moderately toxic to practically non-toxic. (Study

ID 00078663, 00078666, 00078660, 00078657, 249160, 00108109, 00070893, and 249159)

Surfactant Test Findings

Species % AI 48-hr LC50

(95%CL)

Conclusions

Daphnia

magna

100%

MONO818

surfactant

13 mg/L 

(7.1-24) 

slightly toxic to freshwater invertebrates

Testing of the surfactant may be required under unusual circumstances. One test on the surfactant was

received and determined as acceptable for use in a risk assessment. (Study ID 249160) 

(d) Summary of Findings

A 48-hour LC50 of 780 ppm (mg/l) was found

for Daphnia magna exposed to technical glyphosate

(McAllister and Forbis 1978, ID #00108172). The

results of this study indicate that the chemical is

practically non-toxic to aquatic invertebrates.

In addition to these acute studies, a fish lifecycle study indicates technical glyphosate has a
GLYPHOSATE RED

September 1993

48

MATC greater than 25.7 ppm. No effect was

observed at the highest level tested. A Daphnia

magna life cycle study with an MATC of >50 - <96

ppm reported reduced reproductive capacity, the

most sensitive parameter.

The available acute toxicity data indicate that

precautionary labeling for freshwater intervertebrates

is not required for products containing glyphosate.

In order to determine the effect of the three

surfactants ("W", "AA", and "X-77") on invertebrates,

additional Daphnia studies were conducted. The 7.03

percent isopropylamine salt of glyphosate with a

surfactant at 0.5 percent identified as X-77 resulted in

an LC50 of greater than 1000 mg/l or practically nontoxic category for Daphnia. The second combination

was 41.2 percent isopropylamine and 15.3 percent of

a surfactant identified as "AA." This LC50 was 310

ppm which would indicate it is practically non-toxic to

Daphnia. The third combination consisted of 40.7

percent isopropylamine and 15 percent of a surfactant

identified as "W." The resultant LC50 of 72 ppm

reveals that this material is slightly toxic to Daphnia.

A glyphosate formulation was tested several

times with different invertebrates. The LC50 values

ranged from 3 mg/l for Daphnia to 62 mg/l for

Gammarus indicating a moderately toxic material for

Daphnia and no more than slightly toxic for

Gammarus.

(4) Effects on Marine/Estuarine Organisms
GLYPHOSATE RED

September 1993

49

(a) Acute Toxicity

Acute toxicity testing for estuarine and marine

organisms on technical glyphosate is required. The

guidelines require estuarine and marine studies when

exposure of such waters is likely. Crops, such as

cotton, corn, sugarcane, turf, citrus, berries, forestry,

sorghum, watermelon, etc. would allow this type of

exposure to occur.

Acute toxicity testing for estuarine and marine

organisms on formulated glyphosate may be required

when exposure to estuarine and marine water is

expected. The use in drainage systems (wet or dry)

would allow this type of exposure. Minimum

requirements are results from testing the technical on

one estuarine fish (96 hrs LC50) and either a 48 hrs

oyster larvae study or a 96 hrs shell deposition study.

Again, since there is such an extensive data set for

this chemical, the Agency can determine that

glyphosate demonstrates low toxicity to fish and

oyster species, and therefore is waiving the marine

fish and oyster acute toxicity studies on the formulated

product. 

Acute Toxicity to Estuarine and Marine Organisms Findings

Species % AI Results Conclusions

Grass shrimp 96.7%

tech

LC50 281 ppm

(207-381)

ranges in toxicity from slightly to practically non-toxic to

marine organisms

Fiddler crab 96.7%

tech

LC50 934 ppm

(555-1570)

Atlantic oyster 96.7%

tech

TL50 > 10 mg/L

for 48 hours

These data on marine/estuarine species are acceptable for use in a risk assessment. These data indicate

that technical glyphosate is practically non-toxic to grass shrimp, fiddler crab, and slightly toxic to the

Atlantic oyster. Acute toxicity testing on an estuarine fish species is normally required. However, since

there is such an extensive data set for this chemical, the Agency can determine that glyphosate
GLYPHOSATE RED

September 1993

50

demonstrates low toxicity to fish species, and therefore is waiving the marine fish acute toxicity study.

(Study ID 00108110, and 00108111)

(b) Summary of Findings

A series of studies were performed on marine/

estuarine species. A 96-hour LC50 of 281 ppm was

determined for grass shrimp (Palaemonetas

vulgaris). In a study on fiddler crabs (Uca pugilator),

it was determined that the 96-hour LC50 is 934 ppm

glyphosate. Both of these studies indicate technical

glyphosate is practically non-toxic to grass shrimp and

fiddler crabs. An embryo-larvae 48-hour TL50 for

Atlantic oyster greater than 10 ppm indicating

glyphosate is slightly toxic.

(5) Effects on Non-Target Insects

(a) Acute Toxicity Testing

Acute Toxicity to Honeybees Data

Species AI % Results Conclusions

Honeybee 

acute oral 

tech*CP67573 oral LD50 >

100μg/bee

practically non-toxic to honeybees on an acute oral and

acute contact basis

Honeybee

acute oral 

36 % MON2139 oral LD50 >

100μg/bee 

Honeybee 

acute contact

tech*CP67573 contact LD50 >

100μg/bee

Honeybee

acute contact

36 % MON2139 contact LD50 >

100μg/bee

* - The percentage of active ingredient used was not reported.

The guidelines require acute toxicity testing to honeybees on the technical when a herbicide is registered

as a general use herbicide. Given the multitude of use patterns for which this chemical is registered,

acute honeybee toxicity studies are required. Based on these data, glyphosate (CP67573) is considered

practically nontoxic on the basis of acute contact toxicity, as well as on acute oral toxicity. These data

satisfy guideline requirements for nontarget insect studies when glyphosate is used as a general use

herbicide. (Fiche No. 00026489) 
GLYPHOSATE RED

September 1993

51

(b) Summary of Findings

Four studies were conducted, two on technical

glyphosate and two on the formulation MON2139,

consisting of 36 % active ingredient. Results from the

honeybee acute oral toxicity study indicates both

technical and formulated glyphosate are practically

nontoxic to the honey bee with LD50 values greater

than 100 μg/bee. Results from the honeybee acute

contact toxicity study indicates both technical and

formulated glyphosate are practically nontoxic to the

honey bee with LD50 values greater than 100 μg/bee.

(6) Effects to Non-Target Plants

When a herbicide is applied as a terrestrial nonfood

use, aquatic nonfood use, or as a forestry use, Tier I

nontarget phytotoxicity studies are required in order to

evaluate the effects of the herbicide on nontarget plants. 

(a) Phytotoxicity Testing

Effects on Non-Target Plant Findings

Species %AI Results

Selenastrum

capricornutum

96.6 4 day EC50 = 12.5

mg/l

Navicula

pelliculosa

96.6 4 Day EC50 = 39.9

mg/l 

Skeletonema

costatum

96.6 4 day EC50 = 0.85

mg/l

Anabaena flosaquae96.6 4 day EC50 = 11.7

mg/l 

Lemna gibba 96.6 7 day EC50 = 21.5

mg/l

Based on the results of the preceding studies, the data indicates that the 4 day EC50 ranged from 0.85 mg/l

to 39.9 mg/l for four aquatic plant species, and a 7 day EC50 of 21.5 mg/l for one aquatic species. Based
GLYPHOSATE RED

September 1993

52

on the data submitted, the requirements for Tier I and Tier II Aquatic Plant Growth Studies (122-2 and

123-2) have been fulfilled. 

A seed germination/seedling emergence study was conducted (MRID 40159301) on isopropylamine salt

of glyphosate CP-70139 (Tech) 50% acid basis. The results indicate that CP-70139 applied at a rate up

to 10.0 lb ai/A resulted in <25 % effect on the spectrum of monocots and dicots tested. Based on the

results of this study, Tier I data requirements for seed germination/seedling emergence guideline

reference 122-1 have been satisfied. (MRIDs 40236901, 40236902, 40236903, 40236934, and

40236905) 

(b) Summary of Findings

Based on the results of the aquatic plant growth

studies which were conducted on 5 species, the data

indicates that the 4 day EC50 ranged from 0.85 mg/l to

39.9 mg/l for four aquatic plant species, and a 7 day

EC50 of 21.5 mg/l for one aquatic species. 

A seed germination/seedling emergence study

was conducted on isopropylamine salt of glyphosate

CP-70139 (Tech) 50% acid basis. The results

indicate that CP-70139 applied at a rate up to 10.0 lb

ai/A resulted in <25 % effect on the spectrum of

monocots and dicots tested.

Based on the use patterns, the method of

application, and the chemical properties of

glyphosate, additional studies are required to

evaluate the effects on nontarget plants. The

recommended labels do not preclude off-target

movement of glyphosate by drift. Nor do they address

the potential off-target movement via terrestrial plants

as well as aquatic plants. Therefore, the Agency is

requiring terrestrial plant test data to assess potential

risk to nontarget plants. The data required are the

Tier II Vegetative Vigor Guideline Reference No. 123-

1. In addition, droplet size spectrum (201-1) and drift

field evaluation (202-1) data are required.

These three guideline studies, Vegetative

Vigor, Droplet Size Spectrum, and Drift Field

Evaluation are not considered part of the target data

base for reregistration. These data do not affect the
GLYPHOSATE RED

September 1993

53

reregistration eligibility of glyphosate. If, upon review

of the data from these studies, modification in use

practices and/or precautionary measures are

necessary, the Agency will require all registrants to

make label changes as appropriate.

b. Ecological Effects Risk Assessment

Based on the current data, it has been determined that effects

to birds, mammals, fish and invertebrates are minimal. Under certain

use conditions, glyphosate is expected to cause adverse effects to

nontarget aquatic plants. Additional data are needed in order to fully

evaluate the effects of glyphosate on nontarget terrestrial plants. This

includes results from vegetative vigor testing (123-1), droplet size

spectrum (201-1). In addition, the drift field evaluation (202-1) study

must be submitted and reviewed. Risk reduction measures cannot

be recommended until data are submitted and evaluated. 

(1) Non-Endangered Species

(a) Terrestrial Species

The acute oral LD50 found for bobwhite quail

dosed with technical glyphosate is greater than 3851

mg/kg. This indicates that the chemical is practically

non-toxic to an upland game species. On a dietary

basis, the available data indicate that, at most,

technical glyphosate is slightly toxic to both mallards

and bobwhite (LC50 > 4640). The articles of Hoerger

and Kenaga (1972) and Kenaga (1973) were

consulted in order to estimate the maximum

concentration of glyphosate which may occur at the

highest application rate for such sites as, cotton and

corn. The following chart addresses the major

vegetation categories upon which fauna are expected

to feed.

Feed Category Concentrations (ppm)

@ 5.0625 lbs ai/A

Short grass 1215
GLYPHOSATE RED

September 1993

54

Long grass 557

Leafy crops 632

Forage; small insects 294

Pods; large insects 61

Fruit 35

Comparing these residues to the dietary data for both

bobwhite and mallards (LC50 > 4640; 1/5th the LC50 > 928), higher

use rates may produce potentially toxic residues on short grass only

(assuming the LC50 is just over > 4640). Wildlife ingesting

significant amounts of insects, pods and/or fruits should not be

affected by single applications.

Directions for some of the use patterns do indicate that

applications can be repeated. Multiple treatments could potentially

increase residues on dietary items within an extended time period.

Also, the available information suggest that glyphosate is relatively

persistent. The half-life in soil is as high as 90.2 days. However,

avian reproduction studies demonstrated no adverse effects at the

highest level tested, 1000 parts per million. Similarly, 90-day dietary

studies with dogs and rats indicate no significant abnormalities when

the maximum level tested is 2000 parts per million. Based on this,

minimal risk is expected.
GLYPHOSATE RED

September 1993

55

(b) Aquatic Species

Aquatic organisms do not appear to be

sensitive to technical glyphosate. The most sensitive

aquatic invertebrate tested is Chironomus plumosus

with a 48-hr LC50 of 55 ppm which is very near to the

lower limit of the Daphnia chronic MATC of 50 mg/l.

The most sensitive fish species are fathead minnow

and rainbow trout which have 96-hour LC50s of 84.9

and 86 mg/l. Chronic testing for the technical with

fathead minnow provided an MATC of > 25.7 mg/l.

Based on the toxicity and the various EEC's the

Agency has determined technical glyphosate should

not cause acute or chronic adverse effects to aquatic

environments. Therefore, minimal risk is expected to

aquatic organisms from the technical glyphosate.

(c) Terrestrial Plants and Aquatic Macrophytes

A seed germination/seedling emergence study

was conducted on isopropylamine salt of glyphosate

CP-70139 (Tech) 50% acid basis. The results

indicate that CP-70139 applied at a rate up to 10.0 lb

ai/A resulted in <25 % effect on the spectrum of

monocots and dicots tested. Considering the use

patterns that are terrestrial food crop and non-food

crop the above EEC's were considered for evaluating

the effects to nontarget plants. The highest exposure

of 0.404 lb a.i. (from aerial application, mist blower

and sprinkler irrigation) is well below the 10.0 lb a.i./A

rate which resulted in < 25 % effect on the monocots

and dicots tested. Therefore, it has been determined

that the use of glyphosate is not expected to cause

adverse effects on seed germination/seedling

emergence with the various registered use patterns.

(MRID 40159301) 

No vegetative vigor (123-1) plant studies have

been conducted. Based on the use patterns, the

method of application and the chemical properties of
GLYPHOSATE RED

September 1993

56

glyphosate, additional studies are required to

evaluate these effects on nontarget terrestrial plants.

The recommended labeling precautions do not

preclude off-target movement of glyphosate by drift.

To assess potential risk to terrestrial plants the

Agency is requiring additional terrestrial plant test

data, including results from vegetative vigor testing,

droplet size spectrum testing and drift field evaluation.

These data are not part of the target data base for

reregistration. Risk reduction measures cannot be

recommended until data are submitted and evaluated.

If, upon review of the data from these studies,

modification in use practices and/or precautionary

measures are necessary, the Agency will require all

registrants to make label changes as appropriate.

The aquatic EEC from direct application of

3.72 ppm was used to estimate exposure. Based on

the results of the aquatic macrophyte toxicity data, the

4 day EC50 was reported to be as low as 0.85 ppm

indicating that there may be adverse effects to

nontarget aquatic plant species. 

(2) Endangered Species

Based on the toxicity data and the estimated

exposure, it is not expected that endangered terrestrial or

aquatic organisms will be affected from the use of glyphosate

on the registered uses since the EEC's are well below the

endangered species criteria (birds= 1/10 LC50, aquatic

organisms= 1/20 LC50). However, many endangered plants

may be at risk from the use of glyphosate on the registered

use patterns. In addition, as discussed in the 1986

Glyphosate Registration Standard, it was determined that

based on habitat, the Houston Toad may be at risk from the

use of glyphosate on alfalfa.

IV. RISK MANAGEMENT AND REREGISTRATION DECISION

A. Determination of Eligibility
GLYPHOSATE RED

September 1993

57

Section 4(g)(2)(A) of FIFRA calls for the Agency to determine, after

submission of relevant data concerning an active ingredient, whether products

containing the active ingredients are eligible for reregistration. The Agency has

previously identified and required the submission of the generic (i.e. active

ingredient specific) data required to support reregistration of products containing

glyphosate active ingredients. The Agency has completed its review of these

generic data, and has determined that the data are sufficient to support

reregistration of all products containing the isopropylamine and sodium salts of

glyphosate. Appendix B identifies the generic data requirements that the Agency

reviewed as part of its determination of reregistration eligibility of glyphosate, and

lists the submitted studies that the Agency found acceptable.

The data identified in Appendix B were sufficient to allow the Agency to

assess the registered uses of glyphosate and to determine that glyphosate can be

used without resulting in unreasonable adverse effects to man and the environment.

The Agency therefore finds that all products containing glyphosate as the active

ingredients are eligible for reregistration. The reregistration of particular products

is addressed in Section V of this document. 

The Agency made its reregistration eligibility determination based upon the

target data base required for reregistration, the current guidelines for conducting

acceptable studies to generate such data and the data identified in Appendix B.

Although the Agency has found that all uses of glyphosate (isopropylamine and

sodium salt formulations) are eligible for reregistration, it should be understood that

the Agency may take appropriate regulatory action, and/or require the submission

of additional data to support the registration of products containing glyphosate, if

new information comes to the Agency's attention or if the data requirements for

registration (or the guidelines for generating such data) change.

1. Eligibility Decision

Based on the reviews of the generic data for the active ingredient

glyphosate, the Agency has sufficient information on the health effects of

glyphosate and on its potential for causing adverse effects in fish and

wildlife and the environment. The Agency concludes that products

containing glyphosate for all uses are eligible for reregistration. 

The Agency has determined that glyphosate products, labeled and

used as specified in this Reregistration Eligibility Document, will not pose

unreasonable risks or adverse effects to humans or the environment.
GLYPHOSATE RED

September 1993

58

2. Eligible and Ineligible Uses 

The Agency has determined that all uses of glyphosate are eligible

for reregistration.

B. Regulatory Position

The following is a summary of the regulatory positions and rationales for

glyphosate. Where labeling revisions are imposed, specific language is set forth

in Section V of this document.

1. Tolerance Re-assessment

The Agency has determined that aminomethyl phosphonic acid

(AMPA), the metabolite of glyphosate, no longer needs to be regulated and

therefore this compound will be dropped from the tolerance expression.

Also, although the monoammonium salt of glyphosate is not subject to

reregistration, the available data are to allow re-assessment of existing

tolerances for residues resulting from the application of the monoammonium

salt of glyphosate.

Tolerances Listed Under 40 CFR §180.364(a):

The tolerances listed in 40 CFR §180.364(a) are for the combined

residues of glyphosate and its metabolite AMPA resulting from application

of the isopropylamine salt of glyphosate and/or the monoammonium salt of

glyphosate.

Sufficient data are available to ascertain the adequacy of the

established tolerances listed in 40 CFR §180.364(a) for: acerola; alfalfa,

forage, seed, and hay; almonds, hulls; artichokes, Jerusalem; asparagus;

atemoya; avocados; Bahiagrass; bananas; beets, garden, roots;

Bermudagrass; bluegrass; Brassica leafy vegetables group; bromegrass;

bulb vegetables group; carambola; carrots; cereal grains group; citrus fruits

group; coffee beans, green; clover; cotton forage; cotton hay; cottonseed;

cranberries; cucurbit vegetables group; fescue; figs; foliage of legume

vegetables group; fruiting vegetables group; grapes; grass forage, fodder,

and hay group; guavas; horseradish; kiwifruit; leafy vegetables group;

leaves of the root and tuber vegetables group; legume vegetables group;

longan fruit; lychee; mangoes; non-grass animal feeds group, forage and

hay; orchardgrass; papayas; parsnips; passion fruit; peanuts; peanuts,
GLYPHOSATE RED

September 1993

59

vines; pineapple; pistachio; pome fruits group; radishes; rutabagas;

ryegrass; sapodilla; sapote; small fruits and berries group; soybeans;

soybean, forage; stone fruits group; sugar apple; sugar beets; sweet

potatoes; timothy; tree nuts group; turnip roots; wheatgrass; and yams.

Certain commodity definitions of the above tolerances are not in

accordance with the definitions listed in Table II of Subdivision O; see the

tolerance re-assessment table on page 63 for modifications in commodity

definitions.

The established crop group tolerances for the now-obsolete "seed

and pod vegetables" (0.2 ppm) and "seed and pod vegetables, forage and

hay" (0.2 ppm) are inappropriate and are to be replaced with "legume

vegetables group (except soybeans)" and "legume vegetables group,

foliage of (except soybean forage and hay)," respectively. Soybeans must

be excluded from the crop group tolerances because the use pattern for

soybeans is different from other legume vegetables, and the established

tolerance for soybeans and soybean forage and hay differ by a factor >5x

from other legume vegetables. To achieve compatibility with Codex MRLs

for selected commodities, the following actions must be taken (see the table

on page 68): (i) increase U.S. tolerance for legume vegetables group

(except soybeans) from 0.2 ppm to 5 ppm; and (ii) increase U.S. tolerance

for soybean hay from 15 ppm to 20 ppm.

The individual tolerances for cranberries (0.2 ppm) and grapes (0.2

ppm) should be revoked since these fruits are covered by the crop group

tolerance (0.2 ppm) for small fruits and berries. The tolerance for cotton hay

is to be revoked since this is not a raw agricultural commodity of cotton.
GLYPHOSATE RED

September 1993

60

Tolerances for wheat, grain and wheat, straw at 4 and 85 ppm,

respectively, have been proposed (PP0F3865/FAP2H5635). When these

tolerances have been established, the tolerances for the cereal grains group

and the cereal grains group, forage, fodder, and straw should be modified

to "cereal grains group (except wheat)" and "cereal grains group, forage,

fodder, and straw (except wheat straw)", respectively. To achieve

compatibility with the Codex MRL for wheat grain, the U.S. tolerance should

be established at 5 ppm (see the table on page 68).

The existing and conflicting tolerances for alfalfa (200 ppm), alfalfa

fresh and hay (0.2 ppm), clover (200 ppm), and forage legumes (except

soybeans and peanuts; 0.4 ppm) should be deleted. Concomitant with the

deletion of these tolerances, a tolerance of 100 ppm for residues in or on

the non-grass animal feeds group, forage and hay, is to be established.

The available data from alfalfa, lespedeza, and trefoil will support this crop

group tolerance.

The established tolerances for "forage grasses" (0.2 ppm), "grasses,

forage" (0.2 ppm), Bahiagrass (200 ppm), Bermudagrass (200 ppm),

bluegrass (200 ppm), bromegrass (200 ppm), fescue (200 ppm),

orchardgrass (200 ppm), ryegrass (200 ppm), timothy (200 ppm), and

wheatgrass (200 ppm) is to be deleted. Concomitant with the deletion of

these tolerances, a tolerance for residues in on or on the grass forage,

fodder, and hay group is to be established at 100 ppm. The available data

indicate that following registered use, residues in or on the grass forage,

fodder, and hay group will not exceed 100 ppm.

Individual tolerances exist for residues in or on salsify and the

following tropical/subtropical crops: breadfruit; canistel; cherimoya; cocoa

beans; coconut; dates; genip; jaboticaba; jackfruit; persimmons; sapote

(black and white); soursop; and tamarind. There are currently no registered

uses of glyphosate on these crop sites. These tolerances will be revoked.

A tolerance of 200 ppm has recently been established for residues

in or on soybean straw (FR 42701, 9/16/92). However, this tolerance is to

be revoked since this is not a raw agricultural commodity of soybeans. The

tolerance for soybeans, hay should be raised to cover this desiccant use.

The expression negligible residues (N) should be deleted. For a

complete listing of appropriate commodity definition changes and

recommendations, see the table on page 63.
GLYPHOSATE RED

September 1993

61

Tolerances Listed Under 40 CFR §180.364(b):

The tolerances listed in 40 CFR §180.364(b) are for the combined

residues of glyphosate and its metabolite AMPA resulting from application

of the glyphosate isopropylamine salt and/or glyphosate monoammonium

salt for herbicidal and plant growth regulator purposes and/or the sodium

sesqui salt for plant regulator purposes.

Sufficient data are available to ascertain the adequacy of the

established tolerances listed in 40 CFR §180.364(b) for: liver and kidney

of cattle, goats, hogs, horses, poultry, and sheep; peanuts; peanuts, hay;

peanuts, hulls; sugarcane; fish; and shellfish. See the table on page 63 for

modifications in commodity definitions.

Tolerances Listed Under 40 CFR §180.364(c):

The tolerances listed in 40 CFR §180.364(c) are for the combined

residues of glyphosate and its metabolite AMPA resulting from the use of

irrigation water containing residues of 0.5 ppm following applications on or

around aquatic sites, and are established at 0.1 ppm. The Agency's Office

of Water has established a maximum contaminant level (MCL) of 0.7 ppm

for glyphosate per se in drinking water (FR Notice: Vol. 57, No. 138, page

31776, dated July 17, 1992).

Sufficient data are available to ascertain the established tolerances

listed in 40 CFR §180.364(c) for the crop groupings Brassica leafy

vegetables group; bulb vegetables group; cereal grains group; citrus fruits

group; cucurbit vegetables group; foliage of legume vegetables group;

forage, fodder, and straw of the cereal grains group; fruiting vegetables

group; grass forage, fodder and hay group; leafy vegetables group; leaves

of the root and tuber vegetables group; legume vegetables group; nongrass animal feeds group, forage and hay; pome fruits group; root and tuber

vegetables group; stone fruits group; tree nuts group; and the individual

commodities avocados, cottonseed, and hops. See the table on page 63

for modifications in commodity definitions.

Tolerances Listed Under 40 CFR §185.3500:

The tolerances listed in 40 CFR §185.3500(1) are for the combined

residues of glyphosate and its metabolite AMPA resulting from the
GLYPHOSATE RED

September 1993

62

application of the glyphosate for herbicidal purposes and/or the sodium

sesqui salt for plant regulator purposes.

Sufficient data are available to ascertain the adequacy of the

established food additive tolerances listed in 40 CFR §185.3500(1) for

sugarcane, molasses. See the table on page 63 for modifications in

commodity definitions.

The tolerances listed in 40 CFR §185.3500(2) are for the combined

residues of glyphosate and its metabolite AMPA resulting from the

application of the isopropylamine salt of glyphosate for herbicidal purposes.

Sufficient data are available to ascertain the adequacy of the

established food additive tolerances listed in 40 CFR §185.3500(2) for

olives (imported), palm oil, dried tea and instant tea. See the table on page

63 for modifications in commodity definitions.

A 12-ppm food additive tolerance for wheat milling fractions (except

flour) has been proposed (FAP2H5635). To achieve compatibility with the

Codex MRL for wheat bran, unprocessed, the U.S. tolerance should be

established at 40 ppm (see the table on page 68).

Tolerances Listed Under 40 CFR §186.3500:

The tolerances listed in 40 CFR §186.3500(a) are for the combined

residues of glyphosate and its metabolite AMPA.

Sufficient data are available to ascertain the adequacy of the

established feed additive tolerances listed in 40 CFR §186.3500(a) for

dried citrus pulp and soybean hulls. See the table on page 63 for

modifications in commodity definitions.

A tolerance has recently been established at 1.0 ppm for the

combined residues of glyphosate and AMPA in citrus, molasses (FR

42701, 9/16/92).

Existing tolerances of glyphosate are currently established in the Title

40 of the Code of Federal Regulations, §180.364. The reassessment of the

established tolerances is set forth in the Tolerance Reassessment Table as

follows.
GLYPHOSATE RED

September 1993

63

Commodity Current Tolerance 1

(ppm)

Tolerance 2

Reassessment (ppm)

Comment/Correct Commodity

Definition

Tolerances listed under 180.364(a):

Acerola 0.2

Alfalfa

Alfalfa, fresh and hay

Clover

Forage legumes (except

 soybeans and peanuts)

200.0

0.2

200.0

0.4

Revoke and establish at

100

Non-grass animal feeds

 group, forage and hay

Almond hulls 1 Almonds, hulls

Artichokes, Jerusalem 0.2

Asparagus 0.5

Atemoya 0.2

Avocados 0.2

Bahiagrass

Bermudagrass

Bluegrass

Bromegrass

Fescue

Forage grasses

Grasses, forage

Orchardgrass

Ryegrass

Timothy

Wheatgrass

200.0

200.0

200.0

200.0

200.0

0.2

0.2

200.0

200.0

200.0

200.0

Revoke and establish at

100

Grass forage, fodder, and

 hay group

Bananas 0.2

Beets 0.2 Beets, garden, roots

Beets, sugar 0.2 Sugar beets

Breadfruit 0.2 Revoke No registered uses

Canistel 0.2 Revoke No registered uses

Carambola 0.2

Carrots 0.2

Cherimoya 0.2 Revoke No registered uses

Chicory 0.2 Chicory, roots

Citrus fruits 0.2 Citrus fruits group

Cocoa beans 0.2 Revoke No registered uses

Coconut 0.1 Revoke No registered uses

Coffee beans 1 Coffee beans, green

Cotton, forage 15
GLYPHOSATE RED

September 1993

Commodity Current Tolerance 1

(ppm)

Tolerance 2

Reassessment (ppm)

Comment/Correct Commodity

Definition

64

Cotton, hay 15 Revoke Not in Table II, Subdivision O,

PAG

Cottonseed 15

Cranberries 0.2 Revoke Covered under small fruits

 and berries group

Dates 0.2 Revoke No registered uses

Figs 0.2

Forage grasses

Grasses, forage

0.2

0.2

0.2 Forage, fodder, and straw of

 cereal grains group

 (except wheat straw)

Fruits, small and berries 0.2 Small fruits and berries

 group

Genip 0.2 Revoke No registered uses

Grain crops 0.1 Cereal grains group (except

 wheat)

Grapes 0.2 Revoke Covered under small fruits

 and berries group

Guavas 0.2

Horseradish 0.2

Jaboticaba 0.2 Revoke No registered uses

Jackfruit 0.2 Revoke No registered uses

Kiwifruit 0.2 0.1 see Codex Harmonization 

Table

Leafy vegetables 0.2 Leafy vegetables (except

 Brassica) group

and

Leaves of root and tuber

 vegetables group

Longan 0.2 Longan fruit

Lychee 0.2

Mamy sapote 0.2 Sapote

Mangoes 0.2

Nuts 0.2 Tree nuts group

Olives 0.2

Papayas 0.2

Parsnips 0.2 Parsnips, roots

Passion fruit 0.2

Peanut, forage 0.5 Peanuts, vines

Persimmons 0.2 Revoke No registered uses
GLYPHOSATE RED

September 1993

Commodity Current Tolerance 1

(ppm)

Tolerance 2

Reassessment (ppm)

Comment/Correct Commodity

Definition

65

Pineapple 0.1 Pineapples

Pistachio nuts 0.2 Pistachios

Pome fruits 0.2 Pome fruits group

Potatoes 0.2

Radishes 0.2 Radishes, root

Rutabagas 0.2 Rutabagas, root

Salsify 0.2 Revoke No registered uses

Sapodilla 0.2

Sapote, black 0.2 Revoke No registered uses

Sapote, white 0.2 Revoke No registered uses

Seed and pod vegetables 0.2 5 see Codex harmonization

Table;

Legume vegetables group

 (except soybeans)

Seed and pod vegetables,

 forage

Seed and pod vegetables,

 hay

0.2

0.2

0.2 Foliage of legume

 vegetables group (except

 soybean forage and hay)

Soursop 0.2 Revoke No registered uses

Soybeans 20

Soybeans, forage 15

Soybeans, hay 15 200 Raised to cover desiccant use. 

Soybeans, straw 200 Revoke Not in Table II, Subdivision O,

PAG

Stone fruit 0.2 Stone fruits group

Sugar apple 0.2

Sweet potatoes 0.2

Tamarind 0.2 Revoke No registered uses

Turnips 0.2 Turnips, roots

Vegetables, bulb 0.2 Bulb vegetables group

Vegetables, cucurbit 0.5 Cucurbit vegetables group

Vegetables, fruiting (except

 cucurbits) group

0.1 Fruiting vegetables group

Vegetables, leafy, Brassica

 (cole)

0.2 Brassica leafy

 vegetables group

Yams 0.2

Wheat, grain N/A 5.0 see Codex harmonization Table

Wheat, straw N/A 85 (proposed)
GLYPHOSATE RED

September 1993

Commodity Current Tolerance 1

(ppm)

Tolerance 2

Reassessment (ppm)

Comment/Correct Commodity

Definition

66

Tolerances listed under 40 CFR §180.364(b):

Cattle, kidney 0.5 2.0 see Codex harmonization Table

Cattle, liver 0.5 2.0 see Codex harmonization 

Table

Fish 0.25

Goats, kidney 0.5

Goats, liver 0.5

Hogs, kidney 0.5 1.0 see Codex harmonization Table

Hogs, liver 0.5 1.0 see Codex harmonization 

Table

Horses, kidney 0.5

Horses, liver 0.5

Peanuts 0.1

Peanut, hay 0.5 Peanuts, hay

Peanut, hulls 0.5 Peanuts, hulls

Poultry, kidney 0.5

Poultry, liver 0.5

Sheep, kidney 0.5

Sheep, liver 0.5

Shellfish 3.0

Sugarcane 2.0

Tolerances listed under 40 CFR 180.364(c):

Avocados 0.1

Citrus 0.1 Citrus fruits group

Cottonseed 0.1

Cucurbits 0.1 Cucurbit vegetables group

Forage grasses 0.1 Grass forage, fodder, and

 hay group

Forage legumes 0.1 Non-grass animal feeds

 group, forage and hay

Fruiting vegetables 0.1 Fruiting vegetables group

Grain crops 0.1 Cereal grains group

and

Forage, fodder, and straw of

 cereal grains group

Hops 0.1
GLYPHOSATE RED

September 1993

Commodity Current Tolerance 1

(ppm)

Tolerance 2

Reassessment (ppm)

Comment/Correct Commodity

Definition

67

Leafy vegetables 0.1 Leafy vegetables (except

 Brassica) group

and

Brassica (cole) leafy

 vegetables group

Nuts 0.1 Tree nuts group

Pome fruits 0.1 Pome fruits group

Root crop vegetables 0.1 Root and tuber vegetables

 group

and

Leaves of root and tuber

 vegetables group

and

Bulb vegetables group

Seed and pod vegetables 0.1 Legume vegetables group

and

Foliage of legume

 vegetables group

Stone fruit 0.1 Stone fruits group

Tolerances listed under 40 CFR §185.3500(a)(1):

Molasses, sugarcane 30.0 Sugarcane, molasses

Tolerances listed under 40 CFR §185.3500(a)(2):

Oil, palm 0.1 Palm oil, refined

Olives, imported 0.1

Tea, dried 1.0

Tea, instant 7.0 Revoke Not in Table II, Subdivision O,

PAG

Wheat milling fractions

 (except flour)

N/A 40 see Codex harmonization Table 

Tolerances listed under 40 CFR §186.3500(a):

Citrus, pulp, dried 1.0

Citrus molasses 1.0 Citrus, molasses

Soybean hulls 100 Soybeans, hulls

1 Tolerances are for the combined residues of glyphosate and its metabolite AMPA.

2 Tolerances are now for glyphosate per se.
68

CODEX HARMONIZATION TABLE

Several maximum residue limits (MRLs) for glyphosate have been

established by Codex in various commodities. The Codex MRLs (currently

expressed in terms of glyphosate per se) and applicable U.S. tolerances

(expressed in terms of the combined residues of glyphosate and its

metabolite AMPA) are listed in the table below. The Agency has

determined that AMPA no longer needs to be regulated and therefore will

be deleted from the tolerance expression. Based on this determination, the

expression of the U.S. tolerances and the Codex MRLs will be harmonized,

and both will now be expressed in terms of glyphosate per se.

Codex MRLs and applicable U.S. tolerances. Recommendations for

compatibility are based on conclusions following reassessments of U.S.

tolerances (see Tolerance Reassessment Table, above).

Commodity MRL (Step)

 (mg/kg)

U.S. Tolerance

(ppm)

Recommendation

Barley 20 (CXL) 0.1 (Cereal grains group, except wheat)

Beans (dry) 2 (CXL) 0.2 (Legume vegetables group, except

soybeans)

Cattle meat 0.1

(CXL)

Cattle milk 0.1

(CXL)

Cattle, edible offal 2 (CXL) 0.5 (Cattle, liver & kidney) increase U.S. tolerances

Cottonseed 0.5

(CXL)

15

Eggs 0.1

(CXL)

Hay or fodder (dry) of grasses 50 (CXL) 100 (Grass forage, fodder, and hay

group)

Kiwifruit 0.1

(CXL)

0.2 decrease U.S. tolerance

Maize 0.1

(CXL)

0.1 

Oats 20 (CXL) 0.1 (Cereal grains group, except wheat)

Peas (dry) 5 (CXL) 0.2 (Legume vegetables group, except

soybeans)

increase U.S. tolerance

Pig meat 0.1

(CXL)

Pig, edible offal 1 (CXL) 0.5 (Hogs, liver & kidney) increase U.S. tolerances

Poultry meat 0.1

(CXL)

Rape seed 10 (CXL)

Rice 0.1

(CXL)

0.1 (Cereal grains group, except wheat)
Commodity MRL (Step)

 (mg/kg)

U.S. Tolerance

(ppm)

Recommendation

69

Sorghum 0.1

(CXL)

0.1 (Cereal grains group, except wheat)

Soya bean fodder 20 (Step 8) 15 (Soybeans, hay)

Soya bean forage (green) 5 (Step 8) 15 (Soybeans, forage)

Soya bean (dry) 5 (Step 8) 20 (Soybeans)

Soya bean (immature seeds) 0.2

(CXL)

Straw and fodder (dry) of cereal grains 100 (CXL) 0.2 (Forage, fodder, and straw of cereal

grains group, except wheat straw)

Sweet corn (corn-on-the-cob) 0.1

(CXL)

0.1 (Cereal grains group, except wheat)

Wheat 5 (CXL) 4 (proposed) increase U.S. tolerance

proposal

Wheat bran, unprocessed 40 (Step 6) 12 (proposed) increase U.S. tolerance

proposal

Wheat flour 0.5

(Step 8)

Wheat whole meal 5 (Step 8) 12 (proposed)

The following conclusions can be made regarding efforts to harmonize the U.S.

tolerances with the Codex MRLs:

Ë Compatibility between the U.S. tolerances and permanent Codex MRLs

exists in or on: corn (field and sweet); rice; and sorghum.

Ë The levels of U.S. tolerances should be increased, toxicological and

DRES considerations permitting, to achieve compatibility with the Codex

MRLs in or on the following commodities: (i) liver and kidney of cattle

(from 0.5 to 2.0 ppm); (ii) liver and kidney of hogs (from 0.5 to 1.0 ppm);

and (iii) legume vegetables group (except soybeans) (from 0.2 to 5 ppm);

Ë The level of the U.S. tolerance should be decreased to achieve

compatibility with the Codex MRLs in or on kiwifruit (from 0.2 to 0.1 ppm).

Ë The U.S. tolerances in or on the following commodities were based on

registered use patterns in the U.S. and cannot be lowered to achieve

compatibility with the Codex MRLs: (i) grass forage, fodder, and hay

group; (ii) soybeans; and (iii) soybeans, forage.

Ë Wheat grain and wheat bran tolerances of 4 and 12 ppm, respectively,

have been proposed. To achieve compatibility with Codex, these

tolerance levels should be increased, toxicological and DRES

considerations permitting, to 5 and 40 ppm, respectively. 
70

Ë Wide differences (>5x) exist between the U.S. tolerances and permanent

Codex MRLs in or on the following commodities: barley; beans (dry);

soybeans, hay; cottonseed; oats; forage, fodder, and straw of cereal

grains. The decision to harmonize residue levels in or on these

commodities cannot be made at this time. 

Ë No questions of compatibility exist with respect to commodities where: (i)

no Codex MRLs have been established, but U.S. tolerances exist; and (ii)

Codex MRLs have been established, but U.S. tolerances do not exist.

2. Labeling Rationale

While studies show that glyphosate is no more than slightly toxic to birds and is

practically non-toxic to fish and honeybees, a toxic inert in glyphosate end use

products necessitates the labelling of some products "toxic to fish" since some

glyphosate products are applied directly to aquatic environments. 

3. Endangered Species Statement

The Agency does have concerns regarding exposure of endangered plant

species to glyphosate. In the June 1986 Registration Standard, the Agency

discussed consultations with the US Fish and Wildlife Service (FWS) on hazards to

crops, rangeland, silvicultural sites, and the Houston toad which may result from the

use of glyphosate. Because a jeopardy opinion resulted from these consultations, the

agency imposed endangered species labeling requirements in the Registration

Standard to mitigate the risk to endangered species. Since that time, additional plant

species have been added to the list of endangered species. At the present time,

EPA is working with the FWS and other federal and state agencies to develop a

program to avoid jeopardizing the continued existence of all listed species by the use

of pesticides. When the Endangered Species Protection Program is implemented

and subsequent guidance is given, endangered species labeling amendments may

be required on affected end-use products. Labeling statements for end use products

will likely refer users to county specific bulletins specifying detailed limitations on use

to protect endangered species.

V. ACTIONS REQUIRED BY REGISTRANTS

This section specifies the data requirements and responses necessary for the reregistration

of both manufacturing-use and end-use products.

A. Manufacturing-Use Products

1. Additional Generic Data Requirements
71

The generic data base supporting the reregistration of glyphosate for the above

eligible uses has been reviewed and determined to be substantially complete. The

Agency will be calling in data on processed potatoes in a separate DCI. However, the

following additional generic data are required at this time. These additional generic

data are not part of the target data base for glyphosate and do not affect the

reregistration eligibility of glyphosate. (See Appendices for the Generic Data Call-In

Notice.)

Name of Study Guideline Number

Tier II Vegetative Vigor 123-1

Droplet Size Spectrum 201-1

Drift Field Evaluation 202-1

 

2. Labeling Requirements for Manufacturing-Use Products

Effluent Discharge Labeling Statement

All manufacturing-use or end-use products that may be contained in an effluent

discharged to the waters of the United States or municipal sewer systems must bear the

following revised effluent discharge labeling statement.

"Do not discharge effluent containing this product into lakes, streams, ponds,

estuaries, oceans or other waters unless in accordance with the requirements of a National

Pollutant Discharge Elimination System (NPDES) permit and the permitting authority has

been notified in writing prior to discharge. Do not discharge effluent containing this product

to sewer systems without previously notifying the local sewage treatment plant authority. For

guidance contact your State Water Board or Regional Office of the EPA."

All affected products distributed or sold by registrants and distributors (supplemental

registrants) must bear the above labeling by October 1, 1995. All products distributed or

sold by persons other than registrants or supplemental registrants after October 1, 1997

must bear the correct labeling. Refer to PR Notice 93-10 or 40 CFR 152.46(a)(1) for

additional information.

B. End-Use Products

1. Additional Product-Specific Data Requirements

Section 4(g)(2)B) of FIFRA calls for the Agency to obtain any needed productspecific data regarding the pesticide after a determination of eligibility has been
72

made. The product specific data requirements are listed in Appendix G, the Product

Specific Data Call-In Notice.

Registrants must review previous data submissions to ensure that they meet

current EPA acceptance criteria (Appendix F; Attachment E) and if not, commit to

conduct new studies. If a registrant believes that previously submitted data meet

current testing standards, then study MRID numbers should be cited according to the

instructions in the Requirement Status and Registrants Response Form provided for

each product.

2. Labeling Requirements for End-Use Products

The labels and labeling of all products must comply with EPA's current

regulations and requirements as specified in 40 CFR §156.10 and other applicable

documents. Please follow the instructions in the Pesticide Reregistration Handbook

with respect to labels and labeling. Furthermore, the following additional labeling must

be present on glyphosate end-use product labels.

a. Nonaquatic

"Do not apply directly to water, to areas where surface water is present or

to intertidal areas below the mean high water mark. Do not contaminate water

when disposing of equipment washwaters and rinsate."

b. Aquatic

"Do not contaminate water when disposing of equipment washwaters and

rinsate. Treatment of aquatic weeds can result in oxygen loss from

decomposition for dead plants. This loss can cause fish kills."

c. Worker Protection Standard 

Compliance

Any product whose labeling reasonably permits use in the commercial or

research production of an agricultural plant on any farm, forest, nursery, or

greenhouse must comply with the labeling requirements of PR Notice 93-7,

"Labeling Revisions Required by the Worker Protection Standard (WPS), and

PR Notice 93-11, "Supplemental Guidance for PR Notice 93-7," which reflect

the requirements of EPA's labeling regulations for worker protection statements

(40 CFR part 156, subpart K). These labeling revisions are necessary to

implement the Worker Protection Standard for Agricultural Pesticides (40 CFR

Part 170) and must be completed in accordance with, and within the deadlines
73

specified in, PR Notices 93-7 and 93-11. Unless otherwise specifically directed

in this RED, all statements required by PR Notices 93-7 and 93-11 are to be on

the product labeling exactly as instructed in those notices.

After April 21, 1994, except as otherwise provided in PR Notices 93-7 and

93-11, all products within the scope of those notices must bear WPS PR-Noticecomplying labeling when they are distributed or sold by the primary registrant or

any supplementally registered distributor. 

After October 23, 1995, except as otherwise provided in PR Notices 93-7

and 93-11, all products within the scope of those notices must bear WPS PRNotice-complying labeling when they are distributed or sold by any person.

Personal Protective Equipment 

Do not add any additional personal protective equipment requirements to

the labels of glyphosate end-use products, however, any existing personal

protective equipment on those labels must be retained.

Entry Restrictions

Products not Primarily Intended for Home Use 

Uses Within the Scope of the WPS: A 12-hour restricted entry interval (REI)

is required for all uses within the scope of the WPS (see PR Notice 93-7) on all

end-use products, except those intended primarily for home use (see tests in PR

Notice 93-7 and 93-11). This REI should be inserted into the standardized REI

statement required by PR Notice 93-7. The personal protective equipment for

early entry should be the PPE required for applicators of glyphosate, except any

applicator requirement for an apron or respirator is waived. This PPE should

be inserted into the standardized early entry PPE statement required by PR

Notice 93-7." 

Sole-active-ingredient end-use products that contain glyphosate must be

revised to adopt the entry restrictions set forth in this section. Any conflicting

entry restrictions on their current labeling must be removed. 

Multiple-active-ingredient end-use products that contain glyphosate must

compare the entry restrictions set forth in this section to the entry restrictions on

their current labeling and retain the more protective. A specific time-period in

hours or days is considered more protective than "sprays have dried" or "dusts

have settled."
74

Uses Not Within the Scope of the WPS: Do not add any additional entry

restrictions for uses not within the scope of the WPS, however, any entry

restrictions on the current product labeling for those uses must be retained. 

Products Primarily Intended for Home Use: For products primarily intended

for home use (see tests in PR Notice 93-7 and 93-11), do not add any additional

entry restrictions for such products, however, any entry restrictions on the current

product labeling must be retained. 

C. Existing Stocks

Registrants may generally distribute and sell products bearing old labels/labeling

for 26 months from the date of the issuance of this RED. Persons other than the

registrant may generally distribute or sell such products for 50 months from the date

of the issuance of this RED. However, existing stocks time frames will be established

case-by-case, depending on the number of products involved, the number of label

changes, and other factors. Refer to "Existing Stocks of Pesticide Products; State of

Policy"; Federal Register, Volume 56, No. 123, June 26, 1991.

The Agency has determined that registrants may distribute and sell glyphosate

products bearing old labels/labeling for 26 months from the date of issuance of this

RED. Persons other than registrants may distribute or sell such products for 50

months from the date of issuance of this RED.

VI. APPENDICES
75

1. Bolded references were reviewed on 4/26/90. Unbolded references were reviewed in the Residue Chemistry

Science Chapter of the Reregistration Standard dated 7/15/85. Otherwise, references were reviewed as noted.