1

Table of Contents 

1. Executive summary ................................................................................................................. 2

2. Introduction ............................................................................................................................. 3

3. Use Characterization ............................................................................................................... 4

4. Conclusions from Previous Risk Assessments ....................................................................... 8

a. Ecological Risk Assessment ................................................................................................... 8

b. Drinking Water Exposure Assessments ............................................................................. 10

c. Clean Water Act Programs ................................................................................................ 10

5. Environmental Fate and Transport........................................................................................ 11

6. Receptors............................................................................................................................... 25

a. Ecological Incidents ........................................................................................................... 33

7. Analysis Plan ........................................................................................................................ 34

a. Stressors of Concern .......................................................................................................... 34

b. Measures of Exposure ........................................................................................................ 35

c. Measures of Effect ............................................................................................................. 36

8. Endangered Species Assessments ...................................................................................... 36

9. Endocrine Disruptor Screening Program ........................................................................... 36

10. Preliminary Identification of Data Gaps ........................................................................ 37

11. References .......................................................................................................................... 54

Appendix A ............................................................................................................................... 56
2

1. Executive summary

The Environmental Fate and Effects Division (EFED) has completed the preliminary problem 

formulation for the ecological risk, environmental fate, endangered species, and drinking water 

assessments to be conducted as part of the registration review of three Triclopyr herbicidal active 

ingredients. The problem formulation describes the methods and data EFED plans to use during 

the completion of drinking water and ecological risk assessments in support of registration 

review and provides an overview of the environmental fate, ecological effects, and potential risks 

associated with the use of 3 Triclopyr actives: Triclopyr Acid, Triclopyr Triethylamine salt 

(TEA), and Triclopyr butoxyethyl ester (BEE), as well as uncertainties unique to the risk 

assessment of these herbicides. This document also identifies additional studies that would be 

beneficial to the conduct of an ecological risk assessment. Major findings include the following 

environmental fate and ecological effects data gaps: 

Fate Data Needs (see details in Table 18) 

835.2240 Aqueous photolysis using triclopyr acid and xenon arc lamp 

835.4100 Aerobic soil metabolism using triclopyr TEA and BEE 

835.4200 Anaerobic soil metabolism using triclopyr acid, TEA, and BEE 

835.4300 Aerobic aquatic metabolism using triclopyr BEE and degradate TCP 

835.4400 Anaerobic aquatic metabolism using triclopyr BEE 

850.1730 Fish BCF using triclopyr BEE 

Note: since triclopyr is less persistent than other pyridine herbicides (such as picloram, 

clopyralid, etc.), the compost dissipation study required by other pyridine herbicides is not 

required for triclopyr. If needed, triclopyr PRA will bridge data from the compost studies for 

other pyridine herbicides. 

Ecological Effects Data Needs (see details in Table 19) 

850.2100 Avian oral toxicity –Passerine with Triclopyr Acid 

850.1300 Freshwater Invertebrate Lifecycle study with Triclopyr BEE 

850.1350 Estuarine/Marine Invertebrate Lifecycle with Triclopyr BEE 

Special Study Acute oral toxicity to adult honey bees with Triclopyr Acid (OECD 213) 

Special Study Acute oral toxicity to larval honey bees with Triclopyr Acid (OECD 237) 

Special Study Chronic oral toxicity to larval honey bees with Triclopyr Acid 

Special Study Chronic oral toxicity to adult honey bees with Triclopyr Acid 

Uncertainties Associated with the Current Data Gaps 

Due to the lack of chronic lifecycle testing data with freshwater and estuarine/marine aquatic 

invertebrates, there is uncertainty regarding the risk for these organisms when exposed indirectly 

or directly to Triclopyr BEE products via spray drift. In addition, there has only been a single 

species, the Mallard duck, tested for avian oral toxicity with Triclopyr acid., which is both an 

active ingredient and a major degradation end product of the TEA and BEE active ingredients. 

Currently recommended acute oral toxicity data in 40 CFR Part 158 include a passerine species 

of bird due to their potentially greater exposure (on a per body weight basis) and sensitivity to 
3

pesticides. Triclopyr is a systemic herbicide with potential to be transported to bee hives in 

pollen from treated plants. Therefore, there is uncertainty regarding potential effects to 

developing larvae from feeding on residues in the pollen and nectar from treated crops. In 

addition, Triclopyr may be available to adult honeybees in pollen and nectar for extended periods 

of time but data are lacking on effects to adult bees from acute and chronic oral exposure. For 

chronic oral toxicity testing with honey bee larvae, the OECD has a draft guideline for a chronic 

larval toxicity study that may be utilized. It may be possible to conduct the chronic (repeat-dose) 

study in such a way as to derive both an LD50 (acute endpoint of interest) and a NOAEC (chronic 

endpoint of interest) from a single study. If the chronic larval toxicity study is conducted in such 

a way that it derives both an LD50 and NOAEC, then a separate acute larval toxicity study is not 

needed. All of these honey bee toxicity studies are needed in order to evaluate potential risks to 

bees, per the Agency’s recent guidance for assessing pesticide risks to bees.1

 Then need for any 

higher tier studies with bees (e.g., Tier 2 semi-field or Tier 3 field studies) will be determined 

after review of these Tier 1 studies.

2. Introduction

Triclopyr acid (and its salts and esters) are systemic herbicides within the Pyridine carboxylic 

acid chemical family. They are used on limited numbers of crops including rice, on range and 

pasture land, forests, rights of way and on commercial turf such as golf courses. In addition, 

many multi active products containing Triclopyr active ingredients are used on home lawns. 

Triclopyr products control a number of woody plant and weed species. Triclopyr acid has fewer 

registered products than Triclopyr triethylamine salt (TEA) or Triclopyr butoxyethyl ester 

(BEE). Triclopyr TEA rapidly dissociates in water to the triclopyr acid/anion and a potential 

degradate (triethanolamine). Triclopyr BEE hydrolyzes in the environment to the triclopyr 

acid/anion and a potential degradate (butoxyethanol). Since none of the fate studies had 

monitored the triethanolamine and the butoxyethanol parts, their fate remains unknown. Both 

triethanolamine and butoxyethanol are rapidly dissipated by microbial degradation. Triclopyr 

actives breakdown to 3,5,6-trichloro-2-pyridinol (TCP) and other degradation products. 

As described in Section 5, the major stressors of ecological concern are triclopyr TEA and 

triclopyr BEE, and their degradates (triclopyr acid which is also an active ingredient), TCP, and 

3,5,6-Trichloro-2-methoxypyridine (TMP). 

Triclopyr acid penetrates exposed foliage and is also readily absorbed from soils through plant 

roots. Triclopyr is believed to acidify the cell wall by stimulating the activity of a membranebound ATPase proton pump. In low concentrations, triclopyr and other synthetic auxin type 

herbicides cause uncontrolled cell division and growth resulting in vascular tissue destruction. In 

contrast, with higher concentrations, they may inhibit cell division and growth (HRAC MOA 

Classification for Synthetic Auxins - wssa.net/wp-content/uploads/Herbicide MOA Classification). 

Also, auxin type herbicides may cause chlorosis (yellowing of leaves due to lack of chlorophyll), 

and curling or bending of leaves (known as epinasty).

 

1

http://www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/terrestrial_biology_tech_team/Guidance

AssessingPesticideRisk2Bees.pdf 
4

Triclopyr TEA was first registered in 1979 as an herbicide on non-crop areas and in forestry use 

for the control of broadleaf weeds and woody plants. Triclopyr BEE was subsequently registered 

in 1980 for use on the same sites. Both formulations were registered for use on turf sites in 1984. 

In 1985, triclopyr BEE was registered for use on rangeland and permanent grass pastures. Most 

recently (1995), triclopyr TEA was registered for use on rice to control broadleaf weed species. 

3. Use Characterization

Use Sites 

Registered site uses for Triclopyr products include domestic and commercial turf, Christmas tree 

plantations, numerous aquatic areas for aquatic weed control (canals, ponds, irrigation ditches, 

marshes, wetlands, reservoirs, bayous, lake shore, rivers), rangelands, pastures, industrial and 

agricultural structures and surrounding areas, fencerows, public park, wildlife refuge and forest 

lands, ornamental trees, flowering plants and shrubs, rights of way (rail, utility and road), 

airports, athletic fields, military installations, campgrounds and cabins, driveways, fallow land, 

livestock drinking water, and land enrolled in the Conservation Reserve Program (CRP). 

Agricultural crops mentioned on current product labels include rice, alfalfa, almonds, brazil nut, 

butternut, cashews, filberts, hickory nut, macadamia nut, walnuts, hazelnut, cole crops, field 

corn, sweet corn, popcorn, flax, hickory nut, lentils, mint, oats, onions, potatoes, rapeseed, 

sorghum, soybean, sugar beets, sunflower, wheat (forage), blackberries, wild grapes, citrus trees 

(stump injection), apple trees (bark injection), ornamental trees, and vegetable crops (soil 

treatment). 

Nonagricultural tree control uses include ash, birch, black walnut, douglas fir, elm, English 

walnut, gray birch, orchards as stump injection, sugar maple, sweetgum, white birch, white oak, 

white pine, spruce, red pine, mesquite, aspen, birch, dogwood, hackberry, locust, sassafras, red 

maple, red, white and post oak. 

More detailed usage tables for each active (Acid, TEA, and BEE) are attached as addendums to 

this assessment and are obtained from current Agency use site summaries (Office of Pesticide 

Program Information Network OPPIN). In addition, the Biological Economic Analysis Division 

(BEAD) prepared a detailed chemical Profile for triclopyr products on March 13, 2014, which is 

available in the docket. This profile includes a historical look at usage trends on a variety of use 

sites. 

Application Methods 

Methods of application include aerial (fixed wing, rotary and low volume), tree trunk or stump 

injection, bark treatment, foliar spray, soil injection, and ground application as a granular (TEA). 
5

Current Product Registrations 

The current product list for Triclopyr acid is composed of 8 products. Six of these are technical 

and 2 are products containing from 0.76% to 29.4 % triclopyr acid. 

Triclopyr TEA has 88 active products listed with three pending. Twenty-seven of these products 

contain Triclopyr TEA only. Sixty-two products are mixtures with other herbicides such as 

MCPA, Dicamba, 2,4-D (salts and esters), Clopyralid, Trifluralin, Benfluralin, Quinclorac, 

Picloram, Penoxsulam, Propanil, Glyphosate, and Fluroxypyr. A number of them have less 

Triclopyr TEA than the other components. The maximum percent of Triclopyr TEA active 

appears to be 44.4 % for these products. 

Triclopyr BEE has 49 active registered products listed with 3 pending. Eight of these are 

technical products. Twenty-two products contain Triclopyr BEE only at percentages ranging 

from 13.6 to 83.9 %. Twenty-two of the products are multi-active mixtures with other herbicides 

including 2,4-D BEE and 2-EHE, Fluroxypyr 1-MHE, Clopyralid, Sulfentrazone, Dicamba, 

Penoxulam, and Fenoxyprop p-ethyl. Maximum percent of triclopyr BEE active is 61.6 % with 

one exception, Garlon XRT with 83.9 % Triclopyr BEE. 

Formulation types include soluble concentrates, emulsifiable concentrates, liquids-pressurized, 

granules, wettable powders and pellets. A more detailed table of active products for these three 

actives is included as an addendum to this document. 

Potential Acreage based on Current Crops and Usage Estimates 

Based on USDA 2011 pesticide usage estimates for Triclopyr products a very small percentage 

was used on crops with the exception of rice (5-10% of usage). The major uses would appear to 

be for pasture and hay with minor use in orchards or vineyards. Use has declined from 

1,800,000 lbs in 2000 to about 800,000 lbs in 2011. New pesticide usage estimates are expected 

when the 2012 Census estimates are published. BEAD estimates from 1998 to 2012 that an 

average of 1.3 million pounds of acid equivalent (not products) were applied to about 2.75 

million acres annually if based on average percent crop treated. 

Based on Agency maximum percent crop use estimates for the crops using USDA 2007 

Agricultural Census estimates for crop acreages and using maximum percent crop treated 

estimates, the annual number of acres could potentially exceed 11,000,000 acres on a nationwide 

basis. Major Land Use (MLU) estimates were pasture, grassland, and rangeland. These uses do 

not account for aquatic weed control uses, domestic and commercial turf uses, forestry uses, or 

right of way uses which could add significantly to total potential acreage for Triclopyr use. 
6

Table 1. Screening Level Estimates of Agricultural Uses3 of Triclopyr Case (116001, 116002, 

16004) (Reporting Timeframe: 2004-2011) BEAD report date April 19, 2014. 

Percent Crop Treated Acreage Range

Crop Lbs. A.I2

. Average Maximum USDA total (x percent crop1

)

1 Alfalfa (for hay) <500 <1 <2.5 20,244,497(5,061,124)

2 Apples <500 <1 <2.5 398,770 (9969)

3 Corn <500 <1 <2.5 86,248,542 (2,156,213)

4 Fallow (idle cropland) 5,000 <1 <2.5 2,964,000 (74,000) 

5 Hazelnuts (Filberts) <500 <1 <2.5 34,465 (861)

6 Oranges 10,000 <2.5 5785,856 (39,292)

7 Pasture, Range, Grassland 1,000,000 <2.5 <2.5 614,000,000 (1,535,000)

8 Pecans 6,000 <1 <2.5 581,809 (14,545)

9 Rice (2012-2013 data) 90,000 15 25 2,699,000 (674,750)

10 Wheat (2013-2014 data) 2,000 <1 <2.5 56,160,000 ((1,404,000)

1

 BEAD Maximum percent crop used as acreage multiplication factor for potential acreage 

2All numbers rounded. 

3Does not include non-agricultural uses such as commercial turf, rights of way, aquatic uses etc 

<500 Less than 500 pounds of active ingredient

<2.5 Less than 2.5 percent of crop treated

<1 Less than 1 percent of crop treated

No acreage estimates for non-food uses of Triclopyr products such as golf courses, commercial 

buildings, greenhouses and nurseries, residential uses on lawns, ornamental trees and shrubs, 

right of ways, ditches, forests, public parks and aquatic water bodies such as canals, ponds, lakes 

(including reservoirs), rivers, or wetlands have been compiled at this time. These types of 

estimates are quite difficult to conduct. However, it is assumed that this acreage could 

potentially be substantial. In attempting to determine modeling procedures for golf courses, the 

Agency consulted the Golf 20/20 Industry Report for 2002. There were about 15,827 golf 

courses in the United States as of March 2003. Golf course characteristics information provided by 

the Golf Course Superintendents Association of America indicates that an 18-hole golf facility 

averages about 150-200 acres of total land, including water bodies, hard structures, and out-ofplay areas. A typical urban golf course is only 110-120 acres, and courses in resort areas may be 

170-190 acres (G. Lyman, GCSAA; personal communication 11/19/04). Generally, pesticides 

are not applied to entire golf courses, but rather to some holes and some parts of the course (e.g., 

tees, greens, and/or fairways). Based on a median estimate of 150 acres/course multiplied by 

15,827 total courses and reduced to 50% as potential turf area coverage the total potential 

acreage would be over 1,000,000 acres nationwide.

The U.S. Geological Survey (USGS) pesticide use map shows regional scale patterns in use 

intensity within the United States. The USGS pesticide maps are based on State level estimates 

of pesticide use rates for individual crops, which have been compiled by the National Center for 

Food and Agricultural Policy (NCFAP) for 1995-1998, and on recent Census of Agriculture for 

county crop acreage crop. 
7

USGS Caution regarding maps: The pesticide use maps available from this site show regional-scale patterns of 

use intensity within the United States and are not intended for making local-scale estimates of pesticide use, such as 

for individual counties. The maps are based on state-level estimates of pesticide use rates for individual crops, which 

have been compiled by the National Center for Food and Agricultural Policy (NCFAP) and on the recent Census of 

Agriculture county crop acreage. Key limitations include: (1) state use-coefficients represent an average for the 

entire state and consequently do not reflect the local variability of pesticide management practices found within 

many states and counties, and (2) the county-level acreage are based on the Census of Agriculture and may not 

represent all crop acreage due to Census non-disclosure rules. Please refer to Method for Estimating Pesticide Use 

for a detailed discussion of how the pesticide use data were developed. 

Based on label rates examined during the 2009 Endangered Species Assessment California Redlegged Frog2

, maximum single application rates may range from 0.5 to 20 lbs ai/Acre in noncrop areas. This large range of rates is also applied from 1 to up to 17 times per year with 21 day 

intervals between applications. Use on Rice is much more restricted with an application rate of 

0.38 lbs ai/acre and a maximum of 2 applications per year. Direct application to water bodies is 

dependent on the size of the treated area, but limited to a maximum concentration of 2.5 PPM. 

 

2 http://www.epa.gov/espp/litstatus/effects/redleg-frog/#triclopyr 
8

EFED will use application scenarios that result in maximum exposure scenarios for a given use 

for the risk assessment. Any absence of information on the labels that specifies the maximum 

single application rate, the application interval, the annual maximum rate allowed (lbs ai/year), 

or application method may result in conservative assumptions. 

Based on label rates examined during the 2009 Endangered Species Assessment3, maximum 

single application rates may range from 0.5 to 20 lbs ai/Acre in non-crop areas. This large range 

of rates is also applied from 1 to up to 17 times per year with 21 day intervals between 

applications. Use on rice is much more restricted with an application rate of 0.38 lbs ai/acre and 

a maximum of 2 applications per year. Direct application to water bodies is dependent on the 

size of the treated area, but limited to a maximum concentration of 2.5 ppm. 

EFED will use application scenarios that result in maximum exposure scenarios for a given use 

for the risk assessment. Any absence of information on the labels that specifies the maximum 

single application rate, the application interval, the annual maximum rate allowed (lbs ai/year), 

or application method may result in conservative assumptions. Given the relatively high 

application rates and frequencies of some uses (e.g., non-crop areas), additional information to 

clarify or refine labeled uses would be particularly useful for the forthcoming ecological risk 

assessment. 

4. Conclusions from Previous Risk Assessments

a. Ecological Risk Assessment 

The Agency has conducted multiple ecological risk assessments on Triclopyr actives that serve 

as a basis for this scoping document, including the Reregistration Eligibility Decision (RED) in 

1998 and Label revision assessments for TEA (Garlon 3A) aquatic weed control in 2001. Due to 

the rapid dissociation of Triclopyr TEA to Triclopyr Acid within minutes of entering water, the 

exposure of aquatic life from Triclopyr TEA applications was presumed to essentially involve 

the acid form and it’s degradates. Triclopyr BEE is chronically toxic to fish at low levels 

(affecting growth at 48 ug ai/L and reproductive success at 0.99 ug ai/L (MRID 43230201)). 

Therefore, the potential for short-term exposure to the BEE form and subsequent chronic effects 

was not discounted in these assessments. The primary risk issues that have been identified for 

birds and mammals relate to its use on turf at relatively high rates. Risk quotients for aquatic 

plants also exceeded concern levels for this taxonomic group as well. Areas of concern outlined 

in these assessments are briefly summarized below. 

 

3 http://www.epa.gov/espp/litstatus/effects/redleg-frog/#triclopyr 
9

Table 2. Summary of Acute /Chronic Risk Concerns Identified for Triclopyr Acid in Previous 

Assessments (N.D. = not determined) 

Birds Mammals Terr.

Plants

Terr.

Inverts Fish BCF Aqua.Inverts

Aqua.

Plants

Groundwater 

Contamination Persistence Degradates of Concern

Yes1 Yes N.D. N.D. No Unknown No N.D. Groundwater 

advisory

moderate TCP

1 Acute and chronic risks were only predicted for use rates over 8.0 lbs ai/acre. 

Table 3. Summary of Acute/Chronic Risk Concerns Identified for Triclopyr TEA in Previous 

Assessments 

Birds Mammals Terr.

Plants

Terr.

Inverts Fish BCF Aqua.Inverts

Aqua.

Plants

Groundwater 

Contamination Persistence Degradates of Concern

Yes1 Yes2 Yes3 N.D. No Unknown No Yes3 Groundwater 

advisory

moderate TCP

1 Acute concerns for birds feeding on turf (short grass) at 12 lb acid equivalent/acre (lbs ae/A). Endangered species 

concerns exceeded at 3.1 lb ae/A on short grass. Restricted use at 8 lbs ae/Acre on grasses, small insects and 

broadleaf plants. Chronic risk concerns were exceeded for all use rates on grasses, small insects and broadleaf plants 

and for fruits, pods, seeds and large insects at over 6 lbs ae/acre. 

2 chronic risk concerns for small mammals were exceeded for all use rates greater than 1.5 lbs ae/A (short-grass, 

insects). 

3 Acute risks were predicted for all use rates terrestrial/semi aquatic plants and certain aquatic uses (drainage 

systems) and pasture uses for aquatic plants. 

Endangered species concern levels were exceeded for birds, mammals, aquatic plants and terrestrial plants. 

Table 4. Summary of Acute/Chronic Risk Concerns Identified for Triclopyr BEE in Previous 

Assessments

Birds Mammals Terr.

Plants

Terr.

Inverts Fish BCF Aqua.Inverts

Aqua.

Plants

Groundwater 

Contamination Persistence Degradates of Concern

Yes1 Yes2 Yes3 N.D. Yes4 Unknown Yes5 Yes3 Groundwater 

advisory

moderate TCP

1 Acute avian risk were only predicted for forest and aquatic use at over 8.0 lbs acid equivalent/acre on short 

grasses(non-listed) and/or short and long grasses, broadleaf plants and small insects for listed birds. Chronic avian 

risks were predicted for uses over 1.0 lb ai/A. 

2 chronic risk concerns were exceeded for all use rates greater than 6.0 lbs ae/A (3.1 lb ae/A for endangered 

mammals) on short grass and insects. 

3 Acute risks were predicted for all use rates for terrestrial/semi aquatic plants (from runoff or spray drift) and 

certain direct application uses (drainage systems and pasture/forest uses) for aquatic plants. 

4

 Fish acute concerns exceeded for certain pasture, rangeland, and non-ag right of way uses or use around structures 

or fencerows (rates > 8 lb ai/A). Direct applications to water (forest, drainage systems, or streams and rivers for 

aquatic weed control) exceeded at all rates for these uses. 

5 Invertebrate acute concern levels exceeded for direct applications to water (forest, drainage systems, or streams and 

rivers for aquatic weed control) exceeded at nearly all rates for these uses.

Triclopyr actives were also more recently evaluated for potential effects to the California Red 

Legged Frog (CRLF) in 2009. This assessment addressed a much smaller area deemed to be 

biologically relevant to this particular listed species. The species is endemic to California and 

Baja California (Mexico) and inhabits both coastal and interior mountain ranges. A total of 243 

streams or drainages are believed to be currently occupied by the species, with the greatest 

numbers in Monterey, San Luis Obispo, and Santa Barbara counties (U.S. FWS 1996) in 

California. The following conclusions were made in regard to this species. The Agency made a 
10

May Affect, and Likely to Adversely Affect determination for the CRLF based on the 

direct and indirect effects to the aquatic and terrestrial-phase CRLF from the use of 

triclopyr. Additionally, the Agency determined that there is the potential for modification of 

CRLF designated critical habitat from the use of triclopyr. Alteration of plant communities 

within the potentially exposed critical habitats was considered a major source of impact as well 

as indirect effects due to reduction of prey species. Direct exposure to developing larvae and 

adults from forest use, aquatic vegetation control use, and sod or turf farm use were predicted to 

present potential direct acute and chronic effect concerns for this amphibian. 

In May 2004 the Agency completed an Effects Determination for 3 threatened or endangered 

Pacific anadromous salmon and steelhead trout based on triclopyr BEE uses in California 

forestry applications. That Effects Determination concluded that triclopyr BEE would have no 

effect on 1 Evolutionary Significant Units ESU and was Not Likely to Adversely Affect the other 

2 ESUs from registered uses on Forestry in California. In December 2004 the Agency completed 

an Effects Determination for 26 Evolutionary Significant Units(ESUs) of threatened and 

endangered Pacific anadromous salmon and steelhead based on all registered uses of triclopyr 

BEE in the Pacific Northwest and California, consistent with a court order in WTC v. EPA (Case 

No. 1:04-Cv-00126-Ckk, 2004). The results of that endangered species risk assessment showed 

that the use of triclopyr BEE may affect and was likely to adversely affect 16 ESUs and may affect, 

but is not likely to adversely affect, 10 ESUs of Pacific salmon and steelhead when used according 

to labeled application directions. A full copy of the most recent biological Opinion for Pacific 

salmonids can be accessed at www.epa.gov/oppfead1biop.pdf. 

b. Drinking Water Exposure Assessments 

A drinking water exposure assessment on the use of triclopyr TEA in wetlands and the terrestrial 

uses was completed in 2002. EFED used the FIRST model to predict pesticide concentrations 

from wetlands and terrestrial applications and EDWCs were modeled using a scenario of a 

treated wetland adjacent to a drinking water reservoir. For wetland use, the peak drinking water 

concentration of triclopyr acid is 64 ppb. The resulting chronic concentration (annual average in 

Index Reservoir) is 50 ppb. The peak drinking water concentration of TCP is 11 ppb. The 

resulting chronic concentration (annual average in Index Reservoir) is 8.3 ppb. For terrestrial 

use, the peak (acute) and chronic drinking water concentrations for triclopyr acid are estimated to 

be 507 ppb and 88 ppb, respectively. The peak drinking water concentration of TCP is 105 ppb. 

The resulting chronic concentration of TCP is 32 ppb. 

No drinking water exposure assessment was conducted as part of the RED for triclopyr (acid, 

TEA, and BEE) (USEPA 1998). 

c. Clean Water Act Programs 

Triclopyr acid, Triclopyr TEA, Triclopyr BEE, and the TCP degradate have not been identified 

as a cause of impairment for any water bodies listed as impaired under section 303(d) of the 

Clean Water Act. No Total Maximum Daily Load (TMDL) criteria have been developed for 
11

Triclopyr actives. Aquatic benchmarks have been established for all 3 Triclopyr actives and the 

TCP degradate and are available at 

http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_benchmark.htm. 

Any data submitted or otherwise located as part of the registration review process may be used to 

update aquatic life benchmarks if applicable. 

5. Environmental Fate and Transport

Triclopyr acid has a low vapor pressure (1.3x10-6mm Hg) and is highly soluble (water solubility 

of 440 mg/L). Triclopyr TEA is a non-volatile, very soluble salt (vapor pressure < 1 x 10-8 torr; 

solubility 41.2 wt%). Triclopyr BEE is non-volatile (vapor Pressure 3.6 x 10-6mm Hg) and 

shows relatively low solubility (7.4 ppm). Triclopyr acid is a weak acid which will dissociate 

completely to the triclopyr anion at pHs > 5 (dissociation constant pKa 3). Therefore, triclopyr 

anion will be the dominant moiety present in the environment when products containing either 

triclopyr acid or triclopyr TEA are used. However, triclopyr BEE is anticipated to persist longer 

in the environment than triclopyr TEA. Due to its high log Kow and low water solubility, 

Triclopyr BEE is expected to bioaccumulate in fish. Table 5 lists the basic physical and 

chemical properties of triclopyr acid, TEA and BEE. 

Table 5. Physical and Chemical Properties of Triclopyr (Acid, TEA, and BEE). 

Properties Triclopyr Acid Triclopyr TEA Triclopyr BEE

Water Solubility 

(25o C)1

440 ppm 41.2 wt% 7.4 ppm

Vapor Pressure 

(25o C)1

1.3x10-6torr <1.0x10-8

torr 3.6x10-6torr

Henry’s Law 

constant1

9.7x10-7 atm m3 mol-1

1.2x 10-14 atm m3 mol-1 2.5 x 10-7atm m3 mol-1

Log Kow -0.452 0.093 4.012

pKa2 3.0 Dissociates in one 

minute 4

- -

1. EPA. 2009. Risks of Triclopyr Use to Federally Threatened California Red-legged Frog. 

http://www.epa.gov/oppfead1/endanger/litstatus/effects/redleg-frog/triclopyr/analysis.pdf 

2. USDA. 1996. Selected Commercial Formulations of Triclopyr – Garlon 3A and Garlon 4 Risk Assessment. 

Animal and Plant Health Inspection Service (APHIS). USDA. 

http://www.fs.fed.us/r5/hfqlg/publications/herbicide_info/1996b_triclopyr.pdf 

3. California Department of Pesticide Regulation. 1997. Environmental Fate of Triclopyr. 

http://www.cdpr.ca.gov/docs/emon/pubs/fatememo/triclopyr.pdf 

4. Product chemistry (MRID 43011401). Dissociation of Triclopyr Triethylamine Salt. Dow Chemical U.S.A.

Triclopyr Acid 

Based on laboratory studies, triclopyr acid is stable to hydrolysis (MRID 41879601) and 

anaerobic aquatic metabolism (MRID 151967), and it degrades slowly under aerobic aquatic 

conditions (half-life 142 days; MRID 40479101). Triclopyr acid is a weak acid which will 

dissociate completely to the triclopyr anion at pHs > 5 (dissociation constant pKa 3). Therefore, 

the triclopyr anion will be the predominant moiety present in the environment. The very low 
12

KOW for triclopyr acid indicates that it will not be bioaccumulated in fish tissue. Based on the 

preliminary review of a fish bioaccumulation study (MRID 44015101), this is confirmed 

experimentally. It appears that aqueous photolysis is a predominant degradation mechanism in 

aquatic media. Photodegradation of triclopyr acid was less than 1 day in sterile solutions (either 

exposed to mercury lamp or natural sunlight) and approximately 1 day in natural water (exposed 

to natural sunlight) (MRID 41732201). The major photodegradation products observed were 5-

chloro-3,6-dihydroxy-2-pyridinoloxyacetic acid in sterile solutions and oxamic acid in sterile 

natural river water and buffer solutions. 

In soil, the predominant degradation mechanism for triclopyr acid is biotic metabolism. 

Triclopyr acid degraded in aerobic soil with half-lives of 8 to 18 days to intermediate degradates 

3,5,6-trichloro-2-pyridinol (TCP) and 3,5,6-trichloro-2-methoxypyridine (TMP); the ultimate 

degradate is carbon dioxide (MRID 40346304). TCP was also observed as a minor degradate in 

the aerobic aquatic metabolism study (MRID 40479101). Based on adsorption/desorption 

studies, triclopyr acid and its major degradate TCP, both chemicals are expected to be very 

mobile in soils. Freundlich Kads for triclopyr were 0.165-0.975 mL/g (Koc = 53–134; MRID 

40749801). Koc for TCP is 149 (MRID 42493901). 

Triclopyr TEA 

Triclopyr TEA is a salt which is expected to dissociate rapidly in water to the triclopyr 

acid/anion. In measurements of conductance of a solution of triclopyr TEA in water as a 

function of time, triclopyr TEA was found to be dissolved and dissociated completely to the acid 

within one minute (MRID 43011401). Although the triethylamine portion of the triclopyr 

molecule was not monitored, it is reasonable to believe the other hydrolytic product 

(triethylamine) is formed at the same time. As indicated previously, triclopyr acid is expected to 

dissociate completely at environmentally relevant pH values and exist as the triclopyr anion. 

The primary degradation pathway for triclopyr TEA is dissociation to triclopyr acid and 

presumably to triethylamine, because the latter degradate was not monitored in all available fate 

studies. Triethylamine is then degraded by aerobic microbial processes to CO2 (soil half-life 5.6 

– 13.7 days) (MRID 43837501). It is stable in aquatic conditions in the first 14-18 days and then 

proceeds to rapid degradation (half-life 9.3 days in the system; MRID 43837503). Triethylamine 

is stable to degradation under anaerobic aquatic conditions (half-life > 2 years) (MRID 

43837502). Because of the rapid microbial degradation under aerobic conditions, it is not 

expected that volatilization, photodegradation, or bioaccumulation in fish will contribute 

significantly to the dissipation of triethylamine (Kow = 0.09). Triclopyr TEA degraded with 

half-live of 2.2-7.6 days in the water at two study sites in AR and LA and half-lives of 2.9-7.6 

days in the soil in rice field dissipation studies (MRID 43955901). TCP was detected up to 36 

weeks after treatment in vegetated soil; it represented a considerable amount (0.131 ppm) at 63 

weeks (last test interval) in bare soil. 

Triclopyr BEE

Triclopyr BEE will persist to varying degrees in the environment depending on environmental 

conditions and type of study, with persistence in laboratory studies being shorter than that 
13

observed in field studies. In the laboratory, the primary degradation pathway for triclopyr BEE is 

hydrolysis to triclopyr acid, with hydrolysis occurring more rapidly at higher pHs. Triclopyr 

BEE hydrolyzed quickly to triclopyr acid in non-sterile natural waters (pH 6.7; half-life of 0.5 

days; MRID 134174), but somewhat slower at pH 7 in sterile pure water (half-life of 9 days; 

MRID 134174). It appears that hydrolysis occurred more rapidly at higher pH values (half-life 

of 84.0, 9.0 and 0.3 days at pH 5, 7, and 9, respectively) in sterile pure water. Supplemental 

information indicates that triclopyr BEE degrades to triclopyr acid with a half-life of about three 

hours when applied to silty clay loam, silt loam, and sandy loam soils. 

In the field dissipation studies using triclopyr BEE, triclopyr BEE dissipated much faster in NC 

than in CA (with half-lives of 1.1 days and 39 days, respectively; MRID 43033401, 42730601). 

The variation in half lives could be related to the difference in soil pH (NC site has a soil pH of 

6.3 whereas CA site has a pH of 4.7-5.7). In these studies, concentrations of triclopyr acid, TCP, 

and TMP were not found in soil depths below 15 cm (MRID 42730601) or below 30 cm (MRID 

43033401). In the forestry studies, the dissipation half-lives of triclopyr BEE were 15 days on 

foliage, 24 days in pond sediment, 96 days in soil, and 5 days in pond water (MRID 43011601). 

TCP was generally limited to the upper 30 cm of the soil, with sporadic detections in deeper soil 

depths. These observations appear to indicate that TCP is very persistent and mobile in the field 

and that triclopyr BEE may persist under some environmental conditions. 

Triclopyr acid, triclopyr BEE and triclopyr TEA may produce TCP which is relatively mobile 

and persistent and has the potential to reach groundwater. Triclopyr and TCP do not adsorb to 

soil and sediment particles, and may be transported in surface waters; information from two field 

dissipation studies (MRID 43955901) conducted on rice fields indicate that following application 

of triclopyr TEA, TCP can persist in flood waters. Below is a schematic showing the pathways 

for triclopyr acid, TEA, and BEE, and their degradates in hydrolysis, soil and aquatic 

metabolism. 

Since the butoxyethanol part of triclopyr BEE in all fate studies was not monitored, the 

formation and decline of 2-butoxyethanol in the environment remains unknown. According to 

the fate studies of 2,4-D ester salt, 2-butoxyethanol (the test substance) degrades rapidly by 

microbial processes (aerobic soil and aerobic/anaerobic aquatic systems) to 2-butoxyacetic acid 

(half-lives of 0.9–1.4 hours in soil; half-life of 0.6-3.4 days in a sediment/water mixture) (MRIDs 

43799101, 43799103, and 43799106). The degradate (2-butoxyacetic acid) is more persistent 

under anaerobic aquatic conditions than aerobic aquatic conditions (half-lives of 73.3 and 1.4 

days, respectively) (MRIDs 43799103 and 43799106). It is not expected that volatilization will 

contribute significantly to the dissipation of 2-butoxyethanol. Because of the rapid microbial 

degradation, it is not expected that photodegradation or bioaccumulation in fish will contribute 

significantly to the dissipation of butoxyethanol. 

Stressors of Concern 

For the purposes of the forthcoming preliminary risk assessment in registration review, the 

following stressors were evaluated as possible ecological stressors of concern: triclopyr TEA 

and triclopyr BEE, and their degradates (triclopyr acid which it is also an active ingredient, TCP, 

TMP, 5-chloro-3,6-dihydroxy-2-pyridinyloxyacetic acid, oxamic acid, and (5/6)-chloro-3-
14

hydroxy-s-pyridinone. Triclopyr acid, TCP, and TMP were detected in various laboratory fate 

studies as well as in the field dissipation studies. Although TMP is a minor degradate, it was 

included in the field dissipation studies because it is a residue of potential concern. The other 

three degradates (5-chloro-3,6-dihydroxy-2-pyridinyloxyacetic acid, oxamic acid, and (5/6)-

chloro-3-hydroxy-s-pyridinone) were detected only in the aqueous photolysis studies and their 

concentrations increased with time during the duration of the studies. Based on the low toxicity 

estimated from ECOSAR, these three degradates (5-chloro-3,6-dihydroxy-2-pyridinyloxyacetic 

acid, oxamic acid, and (5/6)-chloro-3-hydroxy-s-pyridinone) will not be included in the 

forthcoming environmental fate and ecological risk assessment. . It should be noted that since 

the triethylamine portion of triclopyr TEA and the butoxyethanol portion of triclopyr BEE were 

not monitored in all fate studies, the fate of these two portions in triclopyr TEA and BEE remains 

unknown. Based on the chemical structures, triethylamine and butoxyethanol could be the 

potential degradates from triclopyr TEA and BEE, respectively. ECOSAR suggests that 

triethylamine and butoxyethanol have low toxicity, and are not included as stressors of concern 

at this time. However, additional assessment of triethylamine and butoxyethanol will be 

performed when those studies recommended for submission based on this Problem Formulation 

become available. Therefore, stressors of concern currently include Triclopyr Acid, TEA, BEE, 

TCP and TMP. The decision to include TCP and TMP were based on recent ECOSAR 

projections of toxicity for degradates as well as data submitted to the Agency for Triclopyr acid, 

BEE, and the TCP degradate. The overall degradation pathway for the three active ingredients is 

provided in Figure 1 and a summary of environmental fate studies is provided in Table 6.
15

Figure 1. Degradation pathways for Triclopyr (Acid, TEA, and BEE) 
16

Table 6. Summary of the fate studies for Triclorpyr (acid, TEA, and BEE) 

OCSPP 

Guideline Data Requirement

Submitted Studies 

(MRID and Test 

Substance)

Study Results and Acceptability

835.2120 Hydrolysis

41879601(acid)

134174 (BEE)

Stable at pHs 5, 7, 9 

(Acceptable)

Degrades to acid (t1/2 = 84.0, 9.0 and 0.3 days in 

sterile pH 5, 7 and 9 solutions; t1/2 = 0.5 days in 

non-sterile natural water) 

(Acceptable)

835.2240 Aqueous photolysis

41732201 (acid)

43007601 (BEE)

Degrades rapidly (t1/2=0.4 days)

(Supplemental)

T1/2 = 6.6 days

(Acceptable)

835.2410 Soil photolysis

41323501 (acid)

44329901(acid)

(Unacceptable)

T1/2=40 days

(Acceptable)

835.4100 Aerobic soil 

metabolism

40346304 (acid)

43837501 (degradate 

triethylamine-HCl from 

TEA)

47293801 (BEE)

T1/2 = 8 and 18 days in two soils

(Acceptable)

T1/2= 5.6 and 13.7 days in two soils

(Acceptable)

Preliminary review suggested that BEE degradates 

rapidly to acid (t1/2= 0.3 and 0.7 days in two soils). 

Acid increased continuously to 83% at end of 9-day 

study (In review). 

835.4200 Anaerobic soil 

metabolism --- ---

835.4300 Aerobic aquatic 

metabolism

40479101 (acid)

43837503 (degradate 

triethylamine-HCl from 

TEA)

T1/2 = 142 days

(Acceptable)

T1/2= 9.3 days

(Acceptable)

835.4400 Anaerobic aquatic 

metabolism

43837502 (degradate 

triethylamine-HCl from

TEA)

151967 (BEE)

T1/2 = 2 years

(Acceptable)

Degrades rapidly to acid in two pH 5.7 and pH 6.3 

soils (t1/2 < 1 day). Acid degrades slowly (t1/2 = 

1,300 days). Soils were amended with ground 

alfalfa (Acceptable)

835.1230

835.1240

Adsorption/ 

desorption 

40749801(acid)

42493901 (TCP)

Koc 53-134 in 4 soils

(Acceptable)

Koc 149 in 4 soils

(Acceptable)

Leaching --- ---

835.1410 Volatility-laboratory --- ---
17

OCSPP 

Guideline Data Requirement

Submitted Studies 

(MRID and Test 

Substance)

Study Results and Acceptability

835.8100 Volatility Field --- --

835.6100 Terrestrial field 

dissipation

43033401 (BEE)

42730601 (BEE)

44030601(acid/TCP/TMP 

storage stability data)

T1/2 = 1.1 days

(Acceptable)

T1/2 = 39 days

(Acceptable)

835.6200 Aquatic Field 

Dissipation

43955901(TEA)

44198101 (TMP storage 

data)

41714304 (TEA)

41714305 (TEA)

44456102 (TEA)

44456103 (TEA)

44456104 (TEA)

44039301(storage 

stability data)

T1/2s are 2.2 and 7.6 days 2 in rice water phase at 

two sites; 2.9 and 7.6 days in rice soil phase at two 

sites (Acceptable)

Supplemental

Supplemental 

Supplemental

Supplemental

Supplemental

Acceptable

835.6300 Forest Field 

Dissipation

43011601 (BEE)

44039301 (storage 

stability data)

Acceptable

850.6100

Analytical method in 

water and sediment 

(ECM/ILV)

44456105

44456106

44456109

44456110

44456111

In review 

In review 

In review 

In review 

In review

850.1730 Fish BCF

44015101 (acid; bluegill)

41714307 (TEA; 

crayfish)

Preliminary review indicates BCF of triclopyr acid

in whole fish is 0.2 whereas BCF of total residues in 

whole fish is 0.8 (In review)

BCF 0.5-1.1 in whole fish

(Unacceptable)
18

a. Transformation Products 

The major organic degradates of triclopyr acid, TEA and BEE in submitted environmental fate 

studies were triclopyr acid, 3,5,6-Trichloro-2-pyridinol (TCP), 3,5,6-Trichloro-2-

methoxypyridine (TMP), 5-chloro-3,6-dihydroxy-2-pyridinyloxyacetic acid, oxamic acid, and 

(5/6)-chloro-3-hydroxy-s-pyridinone. In the field dissipation studies for triclopyr TEA and BEE, 

three degradates (acid, TCP and TMP) were monitored. Since the fate of the triethylamine part 

of the triclopyr TEA molecule and the butoxyethanol of the triclopyr BEE molecule was not 

monitored in all fate studies, the formation of triethylamine and 2-butoxyethanol could not be 

confirmed; however, it is expected to occur (see details in Table 7 below).
19

Table 7. Fate Properties of Triclopyr (Acid), Triclopyr TEA, and Triclopyr BEE and their Environmental Degradates 

Code Name/ 

Synonym Chemical Name Chemical Structure Guideline Number

Ref.

(MRID)

Maximum %AR 

(day)

Final %AR 

(study 

length)

PARENT

Triclopyr 

(Triclopyr acid)

IUPAC: 3,5,6-Trichloro-2-pyridyloxyacetic acid

CAS: 2-[(3,5,6-Trichloro-2-pyridinyl)oxy]acetic acid

CAS No.: 55335-06-3

Formula: C7H4Cl3NO3

MW: 256.5 g/mol

SMILES: OC(=O)COc1nc(Cl)c(Cl)cc1Cl

Triclopyr TEA IUPAC: 2-[(3,5,6-Trichloro-2-pyridyl)oxy]acetic 

acid;triethylammonium

CAS: Triclopyr Triethylamine salt

CAS No.: 57213-69-1

Formula: C13H20Cl3N2O3

MW: 358.6 g/mol

SMILES: 

[H][N+](CC)(CC)CC.c1c(c(nc(c1Cl)Cl)OCC(=O)O)Cl
20

Code Name/ 

Synonym Chemical Name Chemical Structure Guideline Number

Ref.

(MRID)

Maximum %AR 

(day)

Final %AR 

(study 

length)

Triclopyr BEE, 

(Triclopyr 2-

butoxyethyl ester, 

Triclopyr 

butoxyethyl ester]

IUPAC: 2-Butoxyethyl 3,5,6-trichloro-2-

pyridyloxyacetate.

2-Butoxyethyl [(3,5,6-trichloropyridin-2-

yl)oxy]acetate

CAS: 2-Butoxyethyl [(3,5,6-trichloro-2-

pyridinyl)oxy]acetate.

Acetic acid, [(3,5,6-trichloro-2-pyridinyl)oxy)-, 2-

butoxyethyl ester 

CAS No.: 64700-56-7

Formula: C13H16Cl3NO4

MW: 356.6 g/mol

SMILES: 

CCCCOCCOC(=O)COc1nc(Cl)c(Cl)cc1Cl

TRANSFORMATION PRODUCTS

Triclopyr 

(Triclopyr acid)

IUPAC: 3,5,6-Trichloro-2-pyridyloxyacetic acid

CAS: 2-[(3,5,6-Trichloro-2-pyridinyl)oxy]acetic acid

CAS No.: 55335-06-3

Formula: C7H4Cl3NO3

MW: 256.5 g/mol

See above 835.2120 134174

BEE degrades to 

triclopyr acid (54.4% at 

Days 10 at pH 7)

-

N

Cl

Cl

Cl

O

C

H2 O

O

C

H2

C

H2

O

C

H2

C

H2

C

H2

CH3
21

Code Name/ 

Synonym Chemical Name Chemical Structure Guideline Number

Ref.

(MRID)

Maximum %AR 

(day)

Final %AR 

(study 

length)

SMILES: OC(=O)COc1nc(Cl)c(Cl)cc1Cl 

835.4400 151967

BEE rapidly degrades to 

triclopyr acid (100% at 

Day 1)

75% at the end of 

study (365 days)

835.6100 43955901

TEA dissipated in rice 

field with half-life of 12 

days in soil and 8 days in 

flood water. Highest 

conc. (0.3 ppb) in water 

was at Days 29).

835.6200 44456104

TEA dissipated in a pond 

with half-life of 6 days in 

water and 4.4 days in 

sediment. The highest 

conc. of triclopyr acid in 

water was 2.4 ppm at 

Day 0).

TCP IUPAC: 3,5,6-Trichloro-2-pyridinol 

CAS: 3,5,6-Trichloropyridinol 

CAS No.: 6515-38-4

Formula:C

5

H

2Cl3NO

MW: 198.4 g/mol

SMILES: Oc1nc(Cl)c(Cl)cc1Cl 

835.2410 44329901 5.1% (Days 19) under 

natural sunlight in CA

4.6% (Days 31) 

under natural 

sunlight in CA

835.4100 40346304

11% in silt loam (Days 

28)

26% in silty clay loam 

(Days 14)

835.4300 40479101 4% (Days 30)-

835.4400 0015167 26% (Days 365)-

835.6100 42730601

BEE dissipated in the 

field with half-life of two 

weeks. TCP was detected 

only in 0-6” soil.

835.6100 43033401 BEE dissipated in the 

field with half-life of 1.1 
22

Code Name/ 

Synonym Chemical Name Chemical Structure Guideline Number

Ref.

(MRID)

Maximum %AR 

(day)

Final %AR 

(study 

length)

days. TCP was detected 

only in 0-12” soil.

835.6100 43955901

TEA dissipated in rice 

field with half-life of 12 

days in soil and 8 days in 

flood water. Highest 

conc. (0.003 ppb) in 

water was at Days 29.

835.6200 44456104

TEA dissipated in a pond 

with half-life of 6 days in 

water and 4 days in 

sediment. Highest conc. 

(5.5 ppb) in water was at 

Day 0).

850.1710 44015101

Preliminary review 

indicates that triclopyr 

acid (which is the test 

substance) accounted for 

24.2% and TCP 

accounted for 23.6% of 

residues in the Days 7 

whole fish extracts.

TMP IUPAC: 3,5,6-Trichloro-2-methoxypyridine

CAS: Pyridine, 2,3,5-trichloro-6-methoxy- pyridine

Formula: C6H4Cl3NO

MW: 212 g/mol

SMILES: COc1c(cc(c(n1)Cl)Cl)Cl

835.4100 40346304

8% in silty loam (Days 

56)

5% in silty clay loam 

(Days 28)

-

835.6100 42730601

BEE dissipated in the 

field with half-life of two 

weeks. TMP was 

detected only in 0-6” soil.
23

Code Name/ 

Synonym Chemical Name Chemical Structure Guideline Number

Ref.

(MRID)

Maximum %AR 

(day)

Final %AR 

(study 

length)

835.6100 43033401

BEE dissipated in the 

field with half-life of 1.1 

days. TMP was detected 

only in 0-12” soil.

835.6100 43955901

TEA dissipated in rice 

field with half-life of 12 

days in soil and 8 days in 

flood water. Highest 

conc. (0.0004 ppb) in 

water was at Days 29.

835.6200 44456104

TEA dissipated in a pond 

with half-life of 6 days 

in water and 4 days in 

sediment. Highest conc. 

(2.2 ppb) in water was at 

Day 1).

850.1710 44015101

Preliminary review 

indicates that TMP 

accounted for 0.4% of 

residues in the whole 

fish extracts.

5-Chloro-3,6-

dihydroxy-2-

pyridinyloxyacetic 

acid

IUPAC: 2-[(5-chloro-3,6-dihydroxy-2-

pyridyl)oxy]acetic acid

Formula: C7H6ClNO5

MW: 219.57 g/mol

SMILES: c1c(c(nc(c1Cl)O)OCC(=O)O)O 

835.2240 41732201

Continuously increased 

to 38% at the end of 12-

hour study in sterile pH 7 

water (mercury lamp) 

Continuously increased 

to 48% at the end of 13-

hour study in sterile pH 7 

water (natural sunlight)

-
24

Code Name/ 

Synonym Chemical Name Chemical Structure Guideline Number

Ref.

(MRID)

Maximum %AR 

(day)

Final %AR 

(study 

length)

Oxamic acid IUPAC: 2-Amino-2-oxoacetic acid

CAS No.: 471-47-6

Formula: C2H3NO3

MW: 89.05 g/mol

SMILES: O=C(O)C(=O)N

835.2240 41732201

Continuously increased 

to 12% at the end of 24-

hour study in sterile river 

water (mercury lamp) 

Continuously increased 

to 16% at the end of 56-

hour study in sterile river 

water (natural sunlight)

-

(5/6)-Chloro-3-

hydroxy-spyridinone

IUPAC: 5,6-Dichloro-3-hydroxy-3H-pyridin-2-one

Formula: C5H3Cl2NO2

MW: 179.98 g/mol

SMILES: C1=C(C(=NC(=O)C1O)Cl)Cl 835.2240 43007601

Continuously increased 

to 17% at the end of 30-

day study in sterile pH 5 

solution (natural 

sunlight) 

-

Triethylamine IUPAC: N,N-Diethylethanamine

CAS No: 121-44-8

Formula: C6H15N

MW: 101.2 g/mol

SMILES: N(CC)(CC)CC

A potential degradate from TEA. However, none of the fate studies 

monitored the formation and decline of the triethylamine portion in 

triclopyr TEA. Note: Triethylamine is a federal hazardous air pollutant 

(http://www.epa.gov/ttn/atw/188polls.html).

IUPAC: Triethylammonium

Formula: C6H16N

MW: 102.1 g/mol

SMILES: CC[NH+](CC)CC

2-Butoxyethanol IUPAC: 2-Butoxyethanol 

Formula: C6H14O2

MW: 118.2 g/mol 

SMILES: O(CCCC)CCO

A potential degradate from BEE. However, none of the fate studies 

monitored the formation and decline of the butoxyethyl portion in 

triclopyr BEE.
25

6. Receptors

The following summaries are based on the studies submitted by the registrants and reviewed by 

the Agency over a period of 35 years in support of Triclopyr actives. A complete table of all 

submitted aquatic and terrestrial organism toxicity data is included in Tables 17 and 18. 

A. Toxicity Summary for Aquatic Organisms: 

Triclopyr Acid 

Triclopyr acid was classified as practically non-toxic to fish and freshwater crustacean on an acute 

basis (Table 8). A single study for the acid with freshwater algae, Selenastrum capricornutum,

produced a 50% growth reduction effect at 32.5 mg a.i./L (ppm) for the technical a.i. No 

estuarine organism or chronic toxicity data for the acid has been submitted to the Agency. 

Triclopyr TEA 

Triclopyr TEA was classified as practically non-toxic to freshwater and marine fish and crustacea 

on an acute basis (Table 9). Chronic effects to freshwater fish and invertebrate were observed at 

concentrations greater than 100 ppm. Triclopyr TEA is slightly toxic to the marine mollusc 

(eastern oyster). The most sensitive algal species, Anabaena flos-aquae, showed a 50% growth 

reduction at 5.9 ppm. The vascular aquatic plant, Lemna gibba, was less sensitive with and EC50

of 19.5 ppm. 

Triclopyr BEE 

Unlike triclopyr acid and the TEA salt, triclopyr BEE was classified as highly toxic to freshwater 

fish and invertebrates and the marine mollusc (LC50/EC50 levels from 0.35 to 0.45 ppm; Table 

10). The butoxyethyl ester was classified as moderately toxic to the estuarine shrimp. Generally, 

the acute toxicity of triclopyr BEE to aquatic animals is two orders of magnitude greater than that 

observed for triclopyr acid or triclopyr TEA. Freshwater algal growth was 50% reduced at 0.1 

ppm and vascular aquatic plant growth was 50% reduced at 0.88 ppm. Chronic effects to the 

freshwater fish were observed at 0.048 ppm. Chronic aquatic invertebrate data for the BEE have 

not been submitted to the Agency at this time. 

TCP 

The TCP degradate was tested and observed to be more toxic than the acid or TEA, but less toxic 

than triclopyr BEE (Table 11). Test results showed slight toxicity to freshwater and marine fish 

and crustacea. It was observed to be moderately toxic to the marine mollusc (eastern oyster). 

Fifty percent reductions in growth were seen at 2.0 ppm for the freshwater algae, Anabaena flosaquae, and 8.2 ppm for the freshwater vascular plant, Lemna gibba.
26

For reference 45% TEA products contain 32.3% acid equivalent and 44% products contain 31.8% 

acid equivalent. Common Triclopyr BEE products such as Garlon 4 at 61.6 % butoxyethyl ester 

contain 44.3% as acid equivalent. Technical Triclopyr BEE at 98% contains 70.4% acid 

equivalent. All results in following tables are expressed as active ingredient. Since the TEA 

disassociates rapidly to the Acid, the most sensitive toxicity value for either TEA or the Acid will 

be used in the forthcoming aquatic ecological risk assessment triclopyr TEA and the Acid. . For 

aquatic risk assessment of Triclopyr BEE (which is mostly expected via spray drift), the toxicity 

values shown for triclopyr BEE in Table 11 will be used. These toxicity values will be 

supplemented with the receipt of any additional data requested of the registrant. 

Table 8. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for Triclopyr Acid 

Taxonomic 

Group

Study Type Surrogate 

Species

Toxicity Value

In PPM (mg ai/L)

Toxicity 

Classification

Source

Freshwater fish1

Acute

Rainbow Trout,

Oncorhynchus 

mykiss

LC50= 117 PPM

Technical 

Practically 

non-toxic

00049637

acceptable

Chronic 

Rainbow Trout or 

Fathead minnow, 

Pimephales 

promelas

No Data

Freshwater 

invertebrates

Acute Water Flea, 

Daphnia magna

EC50= 132.9 PPM w 

technical

Practically 

non-toxic

40346504

acceptable

Chronic Water Flea,

Daphnia magna No data

Estuarine/

marine fish Acute/Chronic No Data

Estuarine/marine 

mollusc Acute No Data

Estuarine/marine 

crustacean Acute/Chronic No Data

Aquatic plants 

and algae

Vascular Duckweed 

,Lemna gibba No data

Non-vascular

Freshwater algae, 

Selenastrum 

capricornutum

EC50 = 32.5 PPM

NOEC = 7.0 PPM 

with technical

41736303

Supplemental

1 Freshwater fish may be surrogates for aquatic-phase amphibians. 

Table 9. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for Triclopyr TEA 

Taxonomic 

Group

Study 

Type

Surrogate Species Toxicity Value

in PPM (mg ai/L)

Acute

Toxicity 

Classificatio

n

Source

Freshwater fish1

Acute

Rainbow trout, 

Oncorhynchus 

mykiss

LC50 = 240 PPM with 

47.8 % ai

Practically 

non-toxic

00062622

acceptable

Chronic 

Fathead minnow, 

Pimephales 

promelas

28 D Early Life Stage

LOAEC= 162 PPM

NOAEC= 104 PPM

00151958

acceptable
27

Taxonomic 

Group

Study 

Type

Surrogate Species Toxicity Value

in PPM (mg ai/L)

Acute

Toxicity 

Classificatio

n

Source

Estuarine/marine 

fish Acute Inland silverside, Menidia beryllina

LC50 = 130 PPM with 

44.7% ai

Practically 

non-toxic

41633703

acceptable

Freshwater 

invertebrate

Acute Water Flea , 

Daphnia magna

EC50 = 775 PPM with 

64.7% ai

Practically 

non-toxic

00151956

acceptable

Chronic Water Flea , 

Daphnia magna

LOAEC= 149 PPM

NOAEC= 80.7 PPM 

with 44.9% ai

00151959

acceptable

Estuarine/

marine mollusc Acute

Eastern Oyster 

(Crassostrea 

virginica)

Larvae EC50=55.7 

PPM

Spat EC50=58 PPM

with 43.8% ai

Slightly toxic 40346606

acceptable

Estuarine/

marine crustacean

Acute

Grass shrimp, 

Palaemonetes pugio

LC50 = 327 PPM with 

46% ai

Practically 

non-toxic

42646102

acceptable

Chronic No chronic data for 

estuarine crustacea

Aquatic plants 

and algae

NonvascularBluegreen algae ,

Anabaena flos-aquae

EC50 = 5.9 PPM

NOAEC = 2.0 PPM

with 45% ai

41633706

acceptable

Vascular Duckweed, Lemna 

gibba

EC50 = 19.5 PPM with 

45% ai

41633709sup

plemental

1 Freshwater fish may be surrogates for aquatic-phase amphibians. 

2 Toxicity endpoints presented, i.e., NOAEC or EC50, are the only ones available from the study. 

Table 10. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for Triclopyr BEE 

Taxonomic 

Group

Study 

Type

Surrogate Species Toxicity Value

In PPM (mg ai/L)

Acute

Toxicity 

Classificatio

n

Source

Freshwater fish1

Acute

Bluegill sunfish, 

Lepomis 

macrochirus

LC50 = 0.36 PPM

with technical Highly toxic 42917901acceptable

Chronic 

Rainbow trout 

Oncorhynchus 

mykiss

Early Life Stage

LOAEC = 0.048 PPM

NOAEC = 0.026 PPM

43230201

acceptable

Estuarine/marine 

fish Acute Inland silverside, Menidia beryllina

LC50 = 0.45 PPM 

with technical Highly toxic 42053901acceptable

Freshwater 

invertebrates

Acute Water Flea, 

Daphnia magna

EC50 = 1.7 PPM with 

technical

Moderately 

toxic

00151963

supplemental

Acute Water Flea, 

Daphnia magna

EC50 = 0.35 PPM 

with 62.4% ai Highly toxic 43442603acceptable

Chronic Water Flea, 

Daphnia magna No chronic data
28

Taxonomic 

Group

Study 

Type

Surrogate Species Toxicity Value

In PPM (mg ai/L)

Acute

Toxicity 

Classificatio

n

Source

Estuarine/marine 

mollusc Acute

Eastern Oyster 

Crassostrea 

virginica

EC50 = 0.46 PPM

NOAEC < 0.30 PPM with 

technical

Highly toxic 41971602

acceptable

Estuarine/marine 

crustacean

Acute Grass shrimp, 

Palaemonetes pugio

LC50 = 2.48 PPM with 

technical

Moderately 

toxic

41971601

acceptable

Chronic No chronic data

Aquatic plants 

and algae

NonvascularFreshwater diatom, 

Navicula pelliculosa

24 hr EC50 = 0.10 PPM

NOAEC = 0.002 PPM 

with technical

42721102

supplemental

Vascular Duckweed, Lemna 

gibba

EC50 = 0.88 PPM

NOAEC < 0.16 PPM

with technical

42719101

acceptable

1 Freshwater fish may be surrogates for aquatic-phase amphibians. 

Table. 11 Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for TCP Degradate 

Taxonomic 

Group

Study 

Type

Surrogate Species Toxicity Value

In PPM (mg ai/L) of 

TCP Metabolite

Acute

Toxicity 

Classification

Source

Freshwater fish1

Acute

Bluegill sunfish , 

Lepomis 

macrochirus

LC50 = 12.5 PPM Slightly toxic 41829003

acceptable

Chronic 

Early 

Life 

Stage

Rainbow trout 

Oncorhynchus 

mykiss

Submitted data was found 

to be invalid

44997301 

invalid

46033201

supplement

Estuarine/marine 

fish Acute Atlantic silverside, Menidia menidia LC50 = 58.4 PPM Slightly toxic 42245901acceptable

Freshwater 

invertebrates

Acute Water Flea 

Daphnia magna

EC50 = 10.4 PPM Slightly toxic 41829005

acceptable

Chronic Water Flea 

Daphnia magna

In review-study lab 

conclusions:

LOAEC = 0.13 PPM

NOAEC= 0.058 PPM

45861301

Estuarine/

marine mollusc Acute

Eastern Oyster 

Crassostrea 

virginica

EC50 = 9.3 PPM Moderately 

toxic

42245903

acceptable

Estuarine/

marine crustacean

Acute Grass shrimp, 

Palaemonetes pugio

LC50 = 83.0 PPM Slightly toxic 42245902 

acceptable

Chronic No data

Aquatic plants 

and algae

Nonvascular

Bluegreen algae, 

Anabaena flosaquae

EC50 = 2.0 PPM

NOAEC = 0.353 PPM

45312003

acceptable

Vascular Duckweed, Lemna 

gibba

EC50= 8.2 PPM

NOAEC= 1.02 PPM

45312002

acceptable
29

1 Freshwater fish may be surrogates for aquatic-phase amphibians. 

B. Toxicity Summary for Terrestrial Organisms 

Triclopyr Acid 

Triclopyr acid was classified as slightly toxic to birds on an acute oral basis with an observed oral 

LD50 of 1698 mg ai/kg and slightly toxic on a dietary basis with an observed dietary LC50 of 2934 

ppm (Table 12). Chronic effects (eggshell thickness) for the acid were noted at 200 ppm for the 

bobwhite quail. Mammalian studies indicate that Triclopyr is practically non-toxic to the 

laboratory rat with and LD50 of 630 to 729 mg ai/Kg bodyweight. A two generation rat study 

with Triclopyr demonstrated an LEL of 250 mg ai/kg bodyweight/day with effects to litter size, 

bodyweight and reduced survival in F1 and F2 litters. The honeybee was not acutely sensitive 

with a contact LD50 of over 100 ug ai/bee. 

Triclopyr TEA 

Triclopyr TEA was classified as practically non-toxic to birds with an oral LD50 of over 3000 ppm 

and a dietary LC50 of 11,000 ppm (Table 13). No avian reproduction studies were submitted for 

the TEA salt. The TEA salt was also not tested for the honeybee. Small mammal testing with the 

laboratory rat showed the TEA salt to be nearly non-toxic on an acute oral basis with and LD50 of 

1847 mg ai/Kg of bodyweight. Terrestrial plant testing with the TEA 46 % technical showed 

25% effects to vegetative vigor at application rates as low as 0.0076 lbs ai/A (sunflower) to > 0.33 

lbs ai/A for less sensitive species such as corn. Early testing with the Garlon 3A formulation 

produced 50% adverse effect to sensitive plants at 0.029 lb ai/A (tomato and grape) to 0.691 lb 

ai/A for less sensitive species (peanut). 

Triclopyr BEE 

Triclopyr BEE was classified as slightly toxic to birds on an acute oral basis with and LD50 of 735 

mg ai/kg for the Bobwhite quail (Table 14). On an acute dietary basis, triclopyr BEE was 

classified as practically non-toxic to birds, with an LC50 of over 5401 ppm for the Mallard duck. 

Both studies were conducted using the technical grade of triclopyr BEE. No chronic avian studies 

have been submitted for the ester. Triclopyr BEE was found to be nearly non-toxic to the 

laboratory rat with an LD50 of 803 mg ai/Kg of bodyweight. Triclopyr BEE was practically nontoxic to the honeybee with a contact LD50 > 100 ug ai/bee for the technical grade. As might be 

expected, triclopyr BEE as the 62% ai Garlon 4 formulation displays effects to growth of juvenile 

terrestrial plants at very low rates of application ranging from 0.0089 for sunflower to 0.802 lbs 

ai/A for wheat. .

TCP 

The TCP degradate data was based on studies conducted for support of triclopyr as well as 

chlorpyrifos. The TCP degradate was classified as practically non-toxic to birds on an acute oral 

and dietary basis with oral acute toxicity > 2000 mg ai/kg for Bobwhite quail and a dietary 

toxicity LC50 of > 5620 ppm for Mallard duck (Table 15). Tests conducted with the laboratory 
30

rat show low toxicity with an acute oral LD50 of 870 mg ai/Kg Bodyweight. TCP was slightly 

more toxic to the laboratory mouse with and LD50 of 380 mg ai/Kg of BW for male mice. No 

acute honeybee or terrestrial plant toxicity data has been received for TCP. 

For terrestrial risk assessment, the most sensitive of the toxicity values for Triclopyr Acid, TEA, 

or BEE will be used, as shown in Table 12-14. 

Table 12. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Triclopyr Acid 

Taxonomic 

Group

Study 

Type

Surrogate Species Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classification

Source 

Birds1

Acute Mallard duck, Anas 

platyrhynchos

LD50 = 1698 mg ai/kg of 

bodyweight

Slightly toxic 40346401 

acceptable

Sub-acute 

dietary

Bobwhite quail, 

Colinus virginianus

LC50 = 2934 mg ai/Kg 

of diet Slightly toxic 40346403 

acceptable

Chronic Mallard duck, Anas 

platyrhynchos

LOAEL= 200 mg ai/Kg 

of diet NOAEL= 100 

mg ai/Kg of diet

00031250 

acceptable

Mammals

Acute Oral Laboratory rat, 

Rattus norvegicus

LD50 = 630 mg/kg/BW

(females) Category III 00031940

Acute 

Inhalation Laboratory rat No data

Chronic Laboratory rat 

Rattus norvegicus

2 gen reproductive 

LOAEL =250 mg/kg/day

NOAEL= 25 mg/kg/day

Decreased 

litter size, 

body wt, and 

litter survival

43545701

Insects Acute 

contact

Honey bee 

Apis mellifera LD50 > 100 ug ai/bee Practically non-toxic

40356602 

acceptable

Terrestrial plants

Seedling 

Emergence

or 

Vegetative 

Vigor

Dicot No data

Monocot No data

1 Birds represent surrogates for terrestrial-phase amphibians and reptiles. 

Table 13. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Triclopyr TEA1 

Taxonomic 

Group

Study Type Surrogate 

Species

Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classification

Source

Birds1 Acute

Mallard duck, 

Anas 

platyrhynchos

LD50 = 3176 mg ai/kg

Practically 

non-toxic

40346501

acceptable
31

Taxonomic 

Group

Study Type Surrogate 

Species

Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classification

Source

Sub-acute dietary

Bobwhite quail, 

Colinus 

virginianus

LC50 = 11,622 ppm

diet (estimated)

Practically 

non-toxic

40346503

acceptable

Chronic

Bobwhite quail, 

Colinus 

virginianus

No Data

Mammals Acute Oral

Laboratory rat 

(Rattus 

norvegicus)

LD50 = 1847 mg/kg 

(males and females) Category III 41443301

Insects Acute contact Honey bee ,

Apis mellifera No data- see acid

Terrestrial 

plants

Seedling Emergence

With 46.5% Triclopyr 

TEA (33.3% AE 

equivalent)

Dicot –

Sunflower, 

Helianthus annuus

EC25 > 1.0 lb ai/A

NOAEL = 1.0 lb ai/A 43129801

acceptable

Monocot – Corn, 

Zea mays

EC25 > 0.333 lb ai/A

NOAEL < 0.333 lb 

ai/A

43129801

acceptable

Terrestrial 

plants

Vegetative Vigor

With 46.5% Triclopyr 

TEA (33.3% AE 

equivalent)

Dicot –

Sunflower, 

Helianthus annuus

EC25 = 0.0076 lb ai/A

NOAEL = 0.0041 lb 

ai/A

43129801

acceptable

Monocot – Corn, 

Zea mays

EC25 = 0.176 lb ai/A

NOAEL= 0.111 lb 

ai/A

43129801

acceptable

1 TEA Molar equivalent = 1.40 for acid equivalent conversions 

Table 14. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Triclopyr BEE 

Taxonomic 

Group

Study Type Surrogate Species Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classificatio

n

Source

Birds Acute Bobwhite quail,

Colinus virginianus

21 day LD50 = 735

mg/kg Slightly toxic 41902002acceptable

Sub-acute 

dietary

Mallard duck, Anas 

platyrhynchos LC50 > 5401 ppm diet Practically non-toxic

41905501

acceptable

Chronic No data for any species 

submitted
32

Taxonomic 

Group

Study Type Surrogate Species Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classificatio

n

Source

Mammals

Acute Oral Laboratory rat ,

Rattus norvegicus

LD50 =803 mg/kg 

(males and females) Category III 40557004

Chronic Laboratory rat, 

Rattus norvegicus

90 day LOAEL=28 

mg/Kg/day

NOAEL = 7 mg./Kg/day

Insects Acute contact Honey bee 

(Apis mellifera L.)

LD50 > 100 ug ai/bee Practically 

non-toxic

41219109

acceptable

Terrestrial 

plants

Seedling 

Emergence

with 

Garlon 4

Dicot – Alfalfa, 

Medicago sativa EC25 = 0.062 lbs ai/A

NOAEL = N.D.

43650001

acceptable

Monocot – Onion, 

Allium cepa EC25 = 0.0732 lb ai/A

NOAEL=0.003 lb ai/A

43650001

acceptable

Terrestrial 

plants Vegetative 

Vigor with 

Garlon 4

Dicot- Sunflower, 

Helianthus annuus EC25 = 0.0089 lb ai/A

NOAEL=0.004 lb ai/A

43650001

acceptable

Monocot EC25 = 0.0089 lb ai/A

NOAEL< 0.089 lb ai/A

43650001

acceptable

1 Triclopyr BEE has a molar ratio of 1.39 to Triclopyr Acid which can be used to convert to Acid equivalents 

Table 15. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for TCP Degradate 

Taxonomic 

Group

Study Type Surrogate Species Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classification

Source

Birds Acute Bobwhite quail,

Colinus virginianus

14 day LD50 >2000

mg ai/kg bodywt

Practically 

non-toxic

41829001

acceptable

Sub-acute 

dietary

Mallard duck, Anas 

Platyrhynchos

LC50 > 5620mg ai/Kg

diet

Practically 

non-toxic

41829002

acceptable

Chronic No data

Mammals Acute Oral Laboratory rat 

(Rattus norvegicus)

LD50 = 794 mg/kg 

(males) Category III 00064938

Mammals Acute Oral Laboratory mouse LD50 = 380 mg/kg 

(males) Category II 00043243

Insects Acute contact Honey bee 

Apis mellifera L)

No data

Terrestrial 

plants

Seedling 

Emergence

and 

Dicot No data 
33

Taxonomic 

Group

Study Type Surrogate Species Toxicity Value

(all units in terms of 

measured active 

ingredient)

Acute 

Toxicity 

Classification

Source

Vegetative 

Vigor

Monocot –

No data

a. Ecological Incidents 

The Ecological Incident Information System (EIIS) is an OPP database that houses ecological 

incidents that have been reported to the Agency. When available, EIIS includes date and location 

of an incident, type and magnitude of effects observed in various species, use(s) of pesticides 

known or suspected of contributing to the incident, and results of any chemical residue analysis or 

other analyses conducted during incident investigation. EIIS incidents are categorized according 

to the certainty that the incident resulted from pesticide exposure. The Avian Monitoring System 

(AIMS) is a database administered by the American Bird Conservancy that contains publicly 

available data on reported avian incidents involving pesticides. Many of the incidents listed in 

this database are also in the EIIS. 

EFEDs Incident Database had numerous incidents in which Triclopyr acid, TEA, or BEE products 

were applied and implicated in adverse effects. Over 100 incidents involving Triclopyr products 

have been recorded in the EIIS system. Most involved damage to non-target terrestrial and 

aquatic plants and one involved a fish kill near a rice field. Thirty four incidents with TEA 

product applications were recorded in EIIS by the Agency. Many dealt with plant damage in 

conjunction with lawn care products and residential uses while 9 involved uses on rice. Nine 

incidents were recorded for Triclopyr BEE and all involved non-target plant damage. There were 

no incidents with terrestrial wildlife reported. All of these incidents will be further analyzed 

during the Registration Review process. 

Exposure Pathways of Concern 

Triclopyr products may be applied as a foliar spray by aerial or ground application equipment. 

For this reason both spray drift and runoff/erosion may be considered primary routes of exposure. 

Triclopyr products are systemic herbicides and therefore residues are expected to collect in plant 

tissues in leaf, root and stem areas of target plants and non-target plants exposed to drift. 

Degradation to the Triclopyr Acid form or the more persistent TCP degradate in or on plants, 

soils or water receiving runoff or drift can be expected within days. Degradation to the TCP 

degradate in water is rapid. TCP is a persistent degradate.

Major pathways for exposure to non-target organisms are summarized below: 

Terrestrial Organisms 

- Direct exposure to residues during application either dermally or via inhalation 

- Exposure to applied residues on foliar surfaces from dermal contact 

- Systemic adsorption by plants of residues through roots or foliar surfaces 
34

- Dietary exposure through feeding on vegetation or insects that have been exposed during 

application either directly or via off target spray drift. 

- Ingestion of residues through drinking water sources such as puddles, irrigation ditches, canals, 

contaminated irrigation water or dew within or adjacent to the application site. 

Aquatic or Semi Aquatic Organisms 

- Exposure via water which has received direct application (aquatic vegetation control) or from 

spray drift for other uses 

- Dermal exposure from spray drift in littoral areas (semi aquatic plants, amphibians and semi 

aquatic insects, and reptiles) near application sites 

- Exposure to residues resulting from runoff originating on treated areas. Degradates, such as 

TCP, may be the more prevalent constituents of this runoff. 

- Dietary ingestion of aquatic or semi aquatic plant tissues that have systemically adsorbed 

Triclopyr or TCP residues 

- Because this chemical is applied directly to water (TEA) or to bogs, marshes, etc (BEE and 

TEA), drinking water and dermal exposure are likely exposure pathways. 

Triclopyr acid, Triclopyr TEA and Triclopyr BEE are considered non-volatile (see page 11, Table 

5). The STIR (Screening Tool for Inhalation Risk) model has predicted that inhalation is an 

unlikely path for ground application at very high rates on turf. As triclopyr products may be 

applied aerially it would seem likely that exposed organisms could inhale aerial droplets directly. 

The SIP (Screening Imbibition Program) model has predicted drinking water may be a relevant 

exposure pathway for the Acid (major degradate of the TEA and BEE products). 

SIP and STIR are described in detail at: 

http://www.epa.gov/oppefed1/models/terrestrial/index.htm. 

7. Analysis Plan

a. Stressors of Concern 

i. Ecological Risk Assessment 

For the purposes of the forthcoming preliminary ecological risk assessment in registration review, 

the potential stressors of ecological concern are triclopyr TEA and triclopyr BEE, and their 

degradates (triclopyr acid which it is also an active ingredient, TCP, TMP, 5-chloro-3,6-

dihydroxy-2-pyridinyloxyacetic acid, oxamic acid, and (5/6)-chloro-3-hydroxy-spyridinone). Triclopyr acid, TCP, and TMP were detected in various laboratory fate studies as 

well as in the field dissipation studies. Although TMP is a minor degradate, it was detected in 

many field dissipation studies. The other three degradates (5-chloro-3,6-dihydroxy-2-

pyridinyloxyacetic acid, oxamic acid, and (5/6)-chloro-3-hydroxy-s-pyridinone) were detected in 

the aqueous photolysis studies and their concentrations increased with time during the duration of 

the studies. 
35

Based on ECOSAR toxicity predictions the TMP degradate (3,5,6-Trichloro-2-methoxypyridine)

and the potential degradate, Triethylamine, are predicted to display toxicity to aquatic organisms. 

The photolytic degradates (5-chloro-3,6-dihydroxy-2-pyridinyloxyacetic acid, oxamic acid and 

(5/6)-chloro-3-hydroxy-s-pyridinone)), and the potential degradates (Triethylammonium and 

butoxyethanol) are predicted to display low toxicity to aquatic organisms. A comparison table of 

ECOSAR predicted aquatic toxicity is included in the Appendix B. 

Therefore, the stressors of concern for terrestrial and aquatic organisms are Triclopyr acid, 

Triclopyr TEA, Triclopyr BEE, TCP and TMP. Submitted ecological studies indicate that 

Triclopyr BEE is substantially more toxic to aquatic organisms than the salt, amine, and acid 

forms. Consequently, Triclopyr BEE will be considered separately for aquatic organisms, as has 

been indicated for 2,4-D, a herbicide with similar acid, amine, and ester forms.4 For terrestrial 

scenarios, the most sensitive endpoint, regardless of the triclopyr form (ester, salt, acid) will be 

used in the risk assessment. 

ii. Drinking Water 

When EFED receives the fate studies for triclopyr acid, TEA, and BEE as requested in this PF, a 

ROCKS meeting and an updated drinking water assessment may be needed as part of the 

Registration Review process. If a new drinking water assessment is needed, EFED will include 

the recently revised percentage crop area (PCA) factors as well as the newly-developed PRZMGW and SWCC models to determine EDWCs in groundwater and surface water. 

b. Measures of Exposure 

Estimates of Triclopyr residue levels on terrestrial surfaces will be produced through use of 

TREX modeling and actual foliar surface dissipation data for the Acid and the TEA, and 

independently the BEE if available. 

Estimates of surface and groundwater monitoring exposure levels will be modeled using the latest 

SWCC modeling for scenarios determined to be of the highest concern. PFAM modeling will be 

utilized for Rice uses. Groundwater exposure potential will be modeled using the latest version of 

the PRZM-GW models. Monitoring programs will also be consulted for data regarding TCP or 

TMP detections in surface or groundwater. 

EFED will use standard available models to evaluate potential exposures to aquatic and terrestrial 

organisms as described at http://www.epa.gov/pesticides/science/models_db.htm. In addition, EFAST and any additional available exposure models may be used to assess use in drains, drain 

lines, irrigation supply systems, waste water systems, sewage systems, sewer lines, and storm 

sewers. E-FAST is described in detail at http://www.epa.gov/oppt/exposure/pubs/efast.htm. 

i. Available Monitoring Data 

 

4 http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0330-0025 
36

The Agency is aware of monitoring conducted by federal and state agencies and this source of 

exposure data will be considered in the assessment to the extent that data on Triclopyr and TCP 

are available. The California Department of Pesticide Regulation (CDPR) has been collecting 

surface water data on triclopyr for many years. Samples were taken in six California counties 

from March 1993 to March 2006. Out of 583 samples, 102 samples contained triclopyr. Other 

new sources of federal or state monitoring data will be researched during the registration review 

process. 

c. Measures of Effect 

Toxicity data presented in Section 3 of this problem formulation will be used to calculate risk 

quotients. Any additional information submitted by the registrant or found in the open literature 

prior to conduct of the risk assessment will also be considered. The open literature studies are 

identified using EPA’s ECOTOXicology database (ECOTOX) (USEPA, 2007c), which employs 

a literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants, and 

wildlife. The evaluation of both sources of data can also provide insight into the direct and 

indirect effects of pesticides on biotic communities from loss of species that are sensitive to the 

chemicals and from changes in structure and functional characteristics of the affected 

communities. For the purposes of deriving risk estimates, the most sensitive endpoint among the 

stressors of concern will be used. For aquatic animals, this will generally be triclopyr BEE. 

8. Endangered Species Assessments 

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the 

Agency will evaluate risks to federally listed threatened and/or endangered (listed) species from 

all registered uses of triclopyr Acid, Triclopyr TEA salt and Triclopyr BEE acid during 

registration review. The process for evaluating potential risks to listed species is further described 

at http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm. and also in the appendices of 

this document. 

9. Endocrine Disruptor Screening Program 

Triclopyr actives are not among the group of 58 pesticide active ingredients on the initial list to be 

screened under the EDSP. Under FFDCA sec. 408(p) the Agency must screen all pesticide 

chemicals. Accordingly, EPA anticipates issuing future EDSP test orders/data call-ins for all 

pesticide active ingredients. Additional details are provided in the appendices of this document. 

For further information on the status of the EDSP, the policies and procedures, the list of 67 

chemicals (actives and inerts), the test guidelines and the Tier 1 screening battery, please visit our 

website: http://www.epa.gov/endo/. 
37

10. Preliminary Identification of Data Gaps 

a. Environmental Fate

Table 16 identifies environmental fate studies that offer data for each guideline requirement, as 

well as study classifications and whether or not further data are needed to support the risk 

assessment. Since the triethylamine part of triclopyr TEA in all available fate studies was not 

monitored, the potential formation and decline of triethylamine is unknown. Although 2-

butoxyethanol could be a potential degradate, none of the fate studies had monitored the fate of 

the butoxyethyl part of triclopyr BEE. Therefore, the Agency recommends the registrant also 

investigates the fate of the triethylamine part in TEA and the butoxyethyl part in BEE in the fate 

studies required in Table 16. For example, the registrant should use triethylamine labeled TEA 

and butoxyethyl labeled BEE in two anaerobic soils. 

Table 16. Submitted Environmental Fate Data for Triclopyr (acid, TEA, and BEE)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies (MRID

and Test 

Substance)

Study Results and 

Acceptability

Are Data 

Needed to 

Conduct 

Risk 

Assessment

Type of Data Required and 

Test Substance

835.2120 Hydrolysis

41879601(acid)

134174 (BEE)

Stable at pHs 5, 7, 9 

(Acceptable)

Degrades to acid (t1/2 

= 84, 9 and 0.3 days

in sterile pH 5, 7 and 

9 solutions; t1/2 = 

0.5 days in nonsterile natural water) 

(Acceptable)

No

N/A

835.2240 Aqueous 

photolysis

41732201 (acid)

43007601 (BEE)

Degradates rapidly 

(t1/2=0.4 days)

(Supplemental)

T1/2 = 6.6 days

(Acceptable)

Yes

Mercury light was used in 

41732201. A new study using 

triclopyr acid and xenon arc 

light is needed.

835.2410 Soil photolysis

41323501 (acid)

44329901(acid)

(Unacceptable)

T1/2=40 days

(Acceptable)

No N/A
38

Table 16. Submitted Environmental Fate Data for Triclopyr (acid, TEA, and BEE)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies (MRID

and Test 

Substance)

Study Results and 

Acceptability

Are Data 

Needed to 

Conduct 

Risk 

Assessment

Type of Data Required and 

Test Substance

835.4100 Aerobic soil 

metabolism

40346304 (acid)

43837501 

(degradate 

triethylamine-HCl 

from TEA)

47293801 (BEE)

T1/2 = 8 and 18 days 

in two soils

(Acceptable)

T1/2= 5.6 and 13.7 

days in two soils

(Acceptable)

Preliminary review 

suggested that BEE 

degradates rapidly to 

acid (t1/2= 0.3 and 

0.7 days in two soils). 

Acid increased 

continuously to 83% 

at end of 9-day study 

(In review). 

Yes

A new study using triethylamine 

labeled TEA and two soils is 

needed. 

A new study using butoxyethyl 

labeled BEE and two soils is 

needed.

835.4200 Anaerobic soil 

metabolism No data No data Yes

New studies using triclopyr

acid , TEA, and BEE in two 

soils are needed (see labeling 

requirements in the aerobic soil 

metabolism section above for 

TEA and BEE)

835.4300 Aerobic aquatic 

metabolism

40479101 (acid)

43837503 

(degradate 

triethylamine-HCl 

from TEA)

T1/2 = 142 days

(Acceptable)

T1/2= 9.3 days

(Acceptable)

Yes

A new study using butoxyethyl 

labeled BEE and two water 

sediment systems is needed.

A study using TCP as the test 

substance that was required in 

the RED is needed.

835.4400 Anaerobic 

aquatic 

metabolism

43837502 

(degradate 

triethylamine-HCl 

from TEA)

151967 (BEE)

T1/2 = 2 years

(Acceptable)

Degrades rapidly to 

acid in two pH 5.7 

and pH 6.3 soils 

(t1/2< 1 day). Acid 

degrades slowly (t1/2 

= 1,300 days). Soils 

were amended with 

ground alfalfa.

(Supplemental)

Yes

A new study using butoxyethyl 

labeled BEE in one neutral or 

alkaline water/sediment system 

is needed. Note – adding 

ground alfalfa to the test system 

is not recommended.
39

Table 16. Submitted Environmental Fate Data for Triclopyr (acid, TEA, and BEE)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies (MRID

and Test 

Substance)

Study Results and 

Acceptability

Are Data 

Needed to 

Conduct 

Risk 

Assessment

Type of Data Required and 

Test Substance

835.1230

835.1240

Adsorption/ 

desorption 

40749801(acid)

42493901 (TCP)

Koc 53-134 in 4 soils

(Acceptable)

Koc 149 in 4 soils

(Acceptable)

No N/A

Leaching --- ---

No N/A

835.1410 Volatilitylaboratory --- --- No N/A

835.8100 Volatility Field --- --- No N/A

835.6100 Terrestrial field 

dissipation

43033401 (BEE)

42730601 (BEE)

44030601(acid/

TCP/TMP storage 

stability data)

T1/2 = 1.1 days

(Acceptable)

T1/2 = 39 days

(Acceptable)

No N/A

835.6200 Aquatic Field 

Dissipation

43955901(TEA)

44198101 (TMP 

storage stability 

data)

41714304 (TEA)

41714305 (TEA)

44456102 (TEA)

44456103 (TEA)

44456104 (TEA)

44039301(storage 

stability data)

T1/2 are 2.2 and 7.6 

days 2 in rice water 

phase at two sites; 2.9 

and 7.6 in rice soil 

phase at two sites

(Acceptable)

T1/2 in water are 0.5-

7.9 days 

(Supplemental)

T1/2 in sediment are 

4.4-6.7days 

(Supplemental)

Stable (Acceptable)

No N/A

835.6300 Forest Field 

Dissipation

43011601 (BEE)

44039301 

(storage stability 

data)

Stable (Acceptable)

No N/A
40

Table 16. Submitted Environmental Fate Data for Triclopyr (acid, TEA, and BEE)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies (MRID

and Test 

Substance)

Study Results and 

Acceptability

Are Data 

Needed to 

Conduct 

Risk 

Assessment

Type of Data Required and 

Test Substance

850.6100 Analytical 

method in 

water, soil, and 

sediment 

(ECM/ILV)

44456105

44456106

44456109

44456110

44456111

In review 

In review 

In review 

In review 

In review

No N/A

850.1730 Fish BCF

44015101 (acid; 

bluegill)

41714307 (TEA; 

crayfish)

Preliminary review 

indicates BCF of 

triclopyr in whole 

fish is 0.2 whereas 

BCF of total residues 

in whole fish is 0.8. 

(In review)

BCF 0.5-1.1 in whole 

fish

(Unacceptable)

Yes

The TEA fish study is waived 

due to low Kow 

A fish study using butoxyethyl 

labeled BEE is needed due to its 

high Kow (Log Kow=4) and 

low water solubility (7.4 ppm at 

25o C)

N/A Compost 

Dissipation No data N/A No

Since triclopyr is less persistent 

than other pyridine herbicides 

(such as picloram, clopyralid, 

etc.), the compost dissipation 

study is not required. If needed, 

triclopyr PRA will bridge data 

from the compost studies 

required for other pyridine 

herbicides. 
41

Ecological Effects 

Table 17 and 18 identify ecological effects studies by MRID that offer data for each guideline 

requirement, as well as study classifications and whether or not further data are needed in order to 

support a particular guideline for risk assessment. Although the ecotoxicity database is not 

complete for each of the active ingredients (Triclopyr acid, TEA, BEE), EFED will bridge 

toxicity data across the three active ingredients where applicable. In some cases, conservative 

assumptions (using the most toxic active ingredient) will be used. This will reduced the need for 

extensive ecotoxicity testing on each of the active ingredients. Rationale for the additional data 

requested is presented below the tables. 

For the major degradate TCP, acute toxicity data are available for birds, laboratory mammals, 

freshwater fish, freshwater invertebrates and aquatic plants. This data is sufficient for the 

registration review risk assessment for triclopyr active ingredients. 

For reference 45% TEA products contain 32.3% acid equivalent and 44% products contain 31.8% 

acid equivalent. Common Triclopyr BEE products such as Garlon 4 at 61.6 % butoxyethyl ester 

contain 44.3% as acid equivalent. 

Table 17. Submitted Aquatic Ecological Effects Data for triclopyr Acid, TEA salt, BEE, and TCP 

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

850.1010 Acute FW 

Invertebrate 

40346504

Water flea, 

Daphnia magna

99.5% 

Technical 

acid

Acceptable

EC50= 132.9 

PPM1

No N.A.

00151959

Water flea, Daphnia 

magna

44.9 % TEA Acceptable

EC50=1496 

ppm

No N.A.

00159956

Water flea, 

Daphnia magna

64.7 % TEA Acceptable

EC50 = 775 

PPM

No N.A.

00151963

Water flea, 

Daphnia magna

96.4 % 

Technical 

BEE 

Supplemental

EC50 = 1.7 

PPM

No N.A.

00151965

Water flea, 

Daphnia magna

96.4 % 

Technical 

BEE

Acceptable

EC50=12 

PPM

No N.A.

43442603

Water flea, 

Daphnia magna

62.3% 

Garlon 4 

TEP

Acceptable

EC50 = 0.35 

PPM 

No N.A.

41205408

Water flea, 

Daphnia magna

TCP 

Degradate

Report ES83L 1978

No N.A.

41829005

Water flea, 

Daphnia magna

99.9 % TCP 

Degradate

Acceptable

EC50 = 10.4 

PPM

No N.A.
42

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

850.1025 Acute 

estuarine 

mollusc 

42646101 

Oyster spat, 

Crassostrea 

virginica

46% TEA Acceptable

Formulated

EC50=58 

PPM

No N.A.

00062623

40346606 

Oyster spat, 

Crassostrea 

virginica

43.8 % TEA Acceptable 

Larvae EC50

= 55.7 PPM

Spat 

EC50=58 

PPM

No N.A.

41971602

Oyster spat, 

Crassostrea 

virginica

96.1 % BEE 

technical

Acceptable

EC50 = 0.46 

PPM

No N.A.

41969903 

Oyster spat, 

Crassostrea 

virginica

62.9 % 

Garlon 4 

Acceptable

EC50 =0.32 

PPM

No N.A.

42245903

Oyster spat, 

Crassostrea 

virginica

99.9% TCP 

Degradate

Acceptable

EC50 = 9.3 

PPM

No N.A.

850.1035 Acute 

Estuarine

/Marine 

Crustacea 

00062623

40346406 

Pink shrimp, 

Penaeus duorarum

43.8 % TEA Supplemental

LC50 = 895 

PPM

No N.A.

00062623

40346406 

Fiddler crab, Uca 

pugilator

43.8 % TEA Supplemental

EC50 > 1000 

PPM

No N.A.

42646102 

Grass shrimp, 

Palaemonetes 

pugio

46 % TEA Acceptable

LC50 = 327

PPM

No N.A.

41971601 

Grass shrimp, 

Palaemonetes 

pugio

96.1 % BEE 

technical

Acceptable

LC50 = 2.48 

PPM

No N.A.

41969902 

Grass shrimp, 

Palaemonetes 

pugio

62.4 % 

Garlon 4

Acceptable

LC50 = 1.7 

PPM

No N.A.

42245902

Grass shrimp, 

Palaemonetes 

pugio

99.9% TCP 

Degradate

Acceptable

EC50 = 83 

PPM

No N.A.
43

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

 

850.1075

Freshwater 

Fish Acute

00049637

Rainbow trout, 

Oncorhynchus 

mykiss and Bluegill 

sunfish, Lepomis 

macrochirus

Technical 

acid

Acceptable

LC50 = 148 

PPM –

Bluegill

And 117 

PPM for 

Rainbow 

trout

No N.A.

40098001

Rainbow trout, 

Oncorhynchus 

mykiss and Bluegill 

sunfish, Lepomis 

macrochirus

43.5 % acid 

formulation

Supplemental

LC50 > 100 

PPM both 

species

No N.A.

00151956

Fathead minnow, 

Pimephales 

promelas Rainbow 

trout, Oncorhynchus 

mykiss and Bluegill 

sunfish, Lepomis 

macrochirus

64.7 % TEA Supplemental

LC50s = 891 

PPM 

Bluegill,

947 PPM 

Fathead 

minnow, and

552 PPM 

Rainbow 

trout

No N.A.

00151958

Fathead minnow, 

Pimephales 

promelas

44.9 % TEA Supplemental

LC50 = 279 

PPM

No N.A.

00062622

Bluegill sunfish, 

Lepomis 

macrochirus

47.8 % TEA Acceptable

LC50 = 240 

PPM

No N.A.

00151963

Fathead minnow, 

Pimephales 

promelas

BEE 

technical

Supplemental

LC50 =2.4 

PPM

No N.A.

00151965

Fathead minnow, 

Pimephales 

promelas

BEE 

Technical

Supplemental

LC50 = 2.31 

PPM

No N.A.

41736304

Coho salmon (fry 

and fingerling), 

Oncorhynchus 

kisutch

99 % BEE 

technical

Supplemental 

data

Not 

conducted to 

guideline 

standards

No N.A.
44

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

41971603

Rainbow trout, 

Oncorhynchus 

mykiss

62.9 % 

Garlon 4

Supplemental

LC50 < 2.7 

PPM

No N.A.

41971604

Bluegill sunfish, 

Lepomis 

macrochirus

62.9 % 

Garlon 4

Supplemental

LC50 = 1.3 

PPM

No N.A.

42884501

Rainbow trout, 

Oncorhynchus 

mykiss

97 % BEE 

technical

Acceptable

LC50 =0.65 

PPM

No N.A.

42917901

Bluegill sunfish, 

Lepomis 

macrochirus

97 % BEE 

technical

Acceptable

LC50 = 0.36 

PPM

No N.A.

43442601

Bluegill sunfish, 

Lepomis 

macrochirus

62 % Garlon 

4

Acceptable

LC50 = 0.44 

PPM

No N.A.

43442602

Rainbow trout, 

Oncorhynchus 

mykiss

62 % Garlon 

4

Acceptable

LC50 = 0.98 

PPM

No N.A.

ACC 229783

Rainbow trout, 

Oncorhynchus 

mykiss and Bluegill 

sunfish, Lepomis 

macrochirus

42 % TEA 

and BEE 

formulation

Acceptable

LC50 = 1.46 

PPM for 

Bluegill and 

1.29 PPM for 

Rainbow 

trout

No N.A.

41205402

Rainbow trout, 

Oncorhynchus 

mykiss and Bluegill 

sunfish, Lepomis 

macrochirus

TCP 

Degradate

Supplemental 

information

No N.A.

41829003

Bluegill sunfish, 

Lepomis 

macrochirus

99.9 % TCP 

Degradate

Acceptable

LC50 = 12.5 

PPM

No N.A.

41829004

Rainbow trout, 

Oncorhynchus 

mykiss

99.9 % TCP 

Degradate

Acceptable

LC50 = 12.6 

PPM

No N.A.
45

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

44585404

Pacific salmonseveral species

Garlon 3A, 

Garlon 4, 

BEE, TCP 

and TMP 

Degradates

Open lit 

supplemental 

data

No N.A.

00028766

Rainbow trout, 

Oncorhynchus 

mykiss, Bluegill 

sunfish, Lepomis 

macrochirus and 

Goldfish, Carassius 

auratus

TCP 

degradate

Not useableincompleteNo N.A.

850.1075 Estuarine/

Marine Fish 

Acute 

41633703

Inland silverside, 

Menidia beryllina

44.7 % TEA Acceptable

LC50 = 130 

PPM

No N.A.

41969901

Inland silverside, 

Menidia beryllina

62.9 % 

Garlon 4

Acceptable

LC50 = 0.45 

PPM 

No N.A.

42053901

Inland silverside, 

Menidia beryllina

96.1% BEE 

technical

Acceptable

LC50 = 0.76 

PPM

No N.A.

42245901

Atlantic silverside, 

Menidia menidia

99.9 % TCP 

Degradate

Acceptable

LC50 = 58.4 

PPM

No N.A.

850.1400 Fish Early 

Life Stage 

00151958

Fathead minnow, 

Pimephales 

promelas

44.9 % TEA Acceptable

LOAEC= 

162 PPM

NOAEC= 

104 PPM

No N.A.

43230201

Rainbow trout, 

Oncorhynchus 

mykiss

97% BEE 

Technical

Acceptable

LOAEC = 

0.048 PPM

NOAEC = 

0.026 PPM

No N.A.

44997301 and 

46033201 amended

Rainbow trout, 

Oncorhynchus 

mykiss

99.7% TCP 

Degradate

Unacceptable Yes further data 

needed with 

TCP 

degradate
46

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

850.1300 Freshwater 

Aquatic 

Invertebrate 

Chronic 

00151959

Waterflea, Daphnia 

magna

44.9 % TEA Acceptable

LOAEC= 

149 PPM

NOAEC= 

80.7 PPM

No N.A.

45861301

Waterflea, Daphnia 

magna

TCP 

Degradate

In review Yes*

Waterflea, Daphnia 

magna

Triclopyr 

BEE

No data Yes Data needed 

with Triclopyr 

BEE technical

850.1350 Estuarine/

Marine 

Invertebrate 

Lifecycle 

Toxicity

No data BEE 

technical

No data Yes Data needed 

with Mysid 

and Triclopyr 

BEE 

technical

850.4400 Aquatic 

Plant 

Vascular

41633709

Duckweed, Lemna 

gibba

45 % TEA Supplemental

EC50 = 19.5

PPM

No N.A.

41736302

Duckweed, Lemna 

gibba

45 % TEA 

Garlon 3

Acceptable

EC50 = 24.4 

PPM

No N.A.

42719101

Duckweed, Lemna 

gibba

97 % BEE 

technical

Acceptable

EC50 = 0.88 

PPM

No N.A.

43230310

Duckweed, Lemna 

gibba

Access BEE 

9%/

Picloram 

IOE 4.7% 

mix

Acceptable

EC50 = 99.8 

PPM

No Considered a 

Picloram 

product

45312002

Duckweed, Lemna 

gibba

99.7 % TCP 

Degradate AcceptableE

C50 = 8.2 

PPM

No

850.5400 Aquatic 

Plant NonVascular

41736303

Green algae, 

Selenastrum 

capricornutum

98.8% 

Technical 

acid

Supplemental

EC50 = 32.5 

PPM

NOEC = 7.0 

PPM

No N.A.

41633705

Green algae, 

Selenastrum 

capricornutum

45 % TEA Acceptable 

EC50 = 39.1 

PPM

No N.A.

41633704

Green algae, 

Selenastrum 

capricornutum

61.3 % BEE 

Garlon 4

Acceptable

EC50 = 5.6 

PPM

No N.A.
47

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

42645901

Green algae, 

Selenastrum 

capricornutum

Access 

=Triclopyr 

BEE 9%/

Picloram 

IOE 4.7% 

mix

Supplemental

EC50 = 4.86 

PPM

No Considered a 

Picloram 

product

45312001

Green algae, 

Selenastrum 

capricornutum

99% TCP 

Degradate

Acceptable

EC50 = 2.9

PPM

No

45312003

Bluegreen algae, 

Anabaena flosaquae

99% TCP 

degradate

Acceptable

EC50 = 2.0 

PPM

No

42721101

Bluegreen algae, 

Anabaena flosaquae

97% 

Technical 

BEE

Supplemental

EC50 = 1.97 

PPM

No N.A.

41633706

Bluegreen algae, 

Anabaena flosaquae

45 %TEA Acceptable

EC50 = 5.9 

PPM

No N.A.

43230307

Bluegreen algae, 

Anabaena flosaquae

Access = 

BEE 9%

Picloram 

IOE 4.7% 

Not

Acceptable

No Considered a 

Picloram 

product

41633708

Freshwater diatom, 

Navicula pelliculosa

45 % TEA Acceptable

EC50 = 15.3 

PPM

No N.A.

42721102

Freshwater diatom, 

Navicula pelliculosa

97% 

Technical 

BEE

Supplemental

24 hr EC50 = 

0.10 PPM

No N.A.

43230301

Freshwater diatom, 

Navicula pelliculosa

Access 

=Triclopyr 

BEE 

9%/Picloram 

IOE 4.7% 

Not 

Acceptable

No Considered a 

Picloram 

product

41633707

Marine diatom, 

Skeletonema 

costatum

45 % TEA Supplemental

EC50 = 14.9 

PPM

No N.A.

42721103

Marine diatom, 

Skeletonema 

costatum

97% 

Technical 

BEE

Supplemental

EC50 = 1.17 

PPM

No N.A.
48

OSCSPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classification 

and Results

Data Needed 

to Conduct 

Assessment?

Type of 

Data 

required

43230304

Marine diatom, 

Skeletonema 

costatum

Access 

=Triclopyr 

BEE 9%/

Picloram 

IOE 4.7% 

mix

Not 

acceptable

No Considered a 

Picloram 

product

1PPM = mg ai/L 

* considered a data gap pending review of the submitted study. 

Table 18. Submitted Terrestrial Ecological Effects Data for Triclopyr Acid, TEA, BEE and TCP 

OSCPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classifications

and results

Further 

Data 

Needed?

Type of Data 

Required

850.2100 Avian Oral 

Acute

40346401 Mallard 

duck, Anas 

platyrhynchos

Technical 

acid

Acceptable

LD50=1698 Mg 

ai/Kg bw

No N.A.

00134178 Mallard 

duck, Anas 

platyrhynchos

64.7 TEA Supplemental

LD50=3175 Mg 

ai/Kg bw

No N.A.

40346501 Mallard 

duck, Anas 

platyrhynchos

64.7 TEA Acceptable

LD50=3176 Mg 

ai/Kg bw

No N.A.

41902002

Bobwhite quail, 

Colinus virginianus

96.1 % 

BEE 

technical

Acceptable

LD50=735

No N.A.

41902003 

Bobwhite quail, 

Colinus virginianus

62.9 % 

Garlon 4

Acceptable

LD50=849.2

No N.A.

41829001 

Bobwhite quail, 

Colinus virginianus

TCP 

Degradate

Acceptable

LD50 > 2000 

mg ai/Kg

No N.A.

00028759

Domestic chicken

TCP 

Degradate 

Supplemental 

LD50 > 1000 

Mg si/Kg

No N.A.

Passerine Species Triclopyr 

Acid

No Data Yes An acute, oral 

toxicity study 

with a passerine 

species is 

requested with 

Triclopyr Acid

850.2300 Avian Acute 

Dietary 

00031249 Mallard 

duck, Anas 

platyrhynchos

99 % 

Technical 

acid

Acceptable

LC50 >5620 

PPM

No N.A.

40346403

Bobwhite quail, 

Colinus virginianus

Technical 

acid

Acceptable

LC50 = 2934 

PPM

No N.A.
49

OSCPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classifications

and results

Further 

Data 

Needed?

Type of Data 

Required

00049638 Coturnix 

quail, Coturnix 

coturnix

TEA 

technical

Supplemental

LC50 = 3272 

PPM

No N.A.

40346502 Mallard 

duck, Anas 

platyrhynchos

64.7% 

TEA

Acceptable

LC50 >10,000

PPM

No N.A.

40346503

Bobwhite quail, 

Colinus virginianus

64.7 % 

TEA

Acceptable

LC50 >10,000 

PPM

No N.A.

00134179 Mallard 

duck, Anas 

platyrhynchos

93 % BEE 

technical

Acceptable 

LC50 >10,000 

PPM

No N.A.

00134180

Bobwhite quail, 

Colinus virginianus

93 % BEE 

technical

Acceptable

LC50= 9026 

PPM

No N.A.

41905501

Bobwhite quail, 

Colinus virginianus

96.1% 

BEE 

technical

Acceptable

LC50 =5401 

PPM

No N.A.

41905502 Mallard 

duck, Anas 

platyrhynchos

96.1 % 

BEE 

technical

Acceptable

LC50>5401 

PPM

No N.A.

41829002 Mallard 

duck, Anas 

platyrhynchos

TCP 

degradate

Supplemental

LC50 > 5620 

PPM

No N.A.

850.2300 Avian 

Reproduction 

00031250 Mallard 

duck, Anas 

platyrhynchos

99% 

Technical 

acid

Acceptable

LOAEL=200 

PPM

No N.A.

00031251

Bobwhite quail, 

Colinus virginianus

99% 

Technical 

acid

Supplemental

LOAEL>500 

PPM

No N.A.

 

850.3020

Honeybee 

Acute

40356602 Honeybee, 

Apis mellifera

99.2% 

Technical 

acid

Acceptable

>100 ug ai/bee

No N.A.

41219109 Honeybee, 

Apis mellifera

97.7% 

Technical 

BEE

Acceptable

> 100 ug ai/bee

No N.A.

42625901 Honeybee, 

Apis mellifera

Access = 

BEE 9% 

Picloram 

EHE 4.7% 

Acceptable

>25 ug 

form./bee

No Considered a 

Picloram 

product

 

850.3030

Honeybee 

Residues on 

Foliage

N.A. N.A. No data No N.A.

NonGuidelineHoneybee 

Oral Acute

N.A. N.A. No data Yes 48 hour 

honeybee oral 
50

OSCPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classifications

and results

Further 

Data 

Needed?

Type of Data 

Required

NonGuidelineHoneybee 

Chronic 

Oral 

Toxicity Test

N.A. N.A. No data Yes 10 day oral 

honeybee 

exposure

NonGuidelineHoneybee 

Larvae 

Chronic 

Toxicity

N.A. N.A. No data Yes 21 day chronic 

exposure test

850.3040, 

OECD 75

Higher Tier 

Bee Studies *

N.A. N.A. No data, Conditionally 

Required

residue and/or 

colony-level 

effects studies

850.4400 Terrestrial 

Plants Tier I 

Seedling 

Emergence

41734301 Ten 

Species Tier I 

Seedling Emergence

63.7 % 

BEE

Acceptable 

EC25 < 9.0 lb 

ai/A all species

No N.A.

41734301 Ten 

Species Tier I 

Seedling Emergence

45.2 % 

TEA

Acceptable

EC25 < 8.0 lb 

ai/A all species

No N.A.

41296501

Species Tier I 

Seedling Emergence

Access 9% 

Triclopyr 

BEE with 

4.7% 

Picloram

Supplemental

Drybean EC25 

= 0.000004 lb 

ai/A

No Considered a 

Picloram 

product

850.4450 Terrestrial 

Plants Tier 

I Vegetative 

Vigor

41784401 Ten 

Species Tier I 

Vegetative Vigor

45.2 % 

TEA

Acceptable

EC25<9.0 lb 

ai/A all species

No N.A.

41734301 Ten 

Species Tier I 

Vegetative Vigor

63.7 % 

BEE

Acceptable

EC25<8.0 lb 

ai/A all species

No N.A.

41296501

Species Tier I 

Vegetative Vigor

Access 9% 

Triclopyr 

BEE with 

4.7% 

Picloram

Supplemental

Soybean EC25 

= 0.0002 lb 

ai/A

No Considered a 

Picloram 

product

850.4400 Terrestrial 

Plants Tier 

II Seedling 

Emergence

43129801 Ten 

Species Tier II 

Seedling Emergence

46.5 % 

TEA salt

Acceptable

Corn 

EC25>0.333 lb 

ai/A

No N.A.

43276601 Tier II 

Seedling Emergence

Access 9% 

Triclopyr 

BEE with 

4.7% 

Picloram

Acceptable

Lima bean 

EC25 0.00042 

lb ai/A

No Considered a 

Picloram 

product
51

OSCPP 

Guideline

Data 

Requirement Submitted Studies 

(MRID)

Test 

Material

Study 

Classifications

and results

Further 

Data 

Needed?

Type of Data 

Required

43650001 Ten 

Species Tier II 

Seedling Emergence

62.2% 

Garlon 4

Triclopyr 

BEE

Acceptable

Alfalfa 

EC25=0.062 lb 

ai/A

No N.A.

850.4150 Terrestrial 

Plants Tier 

II Vegetative 

Vigor

43129801 Ten 

Species Tier II 

Vegetative Vigor

46.5 % 

TEA salt

Acceptable

Sunflower 

EC25 = 0.0076 

lb ai/A

No N.A.

43650001 Ten 

Species Tier II 

Vegetative Vigor

62.2% 

Garlon 4

Triclopyr 

BEE

Acceptable

Sunflower 

EC25 =0.0089 

lb ai/A

No N.A.

NonGuideline

ACC 235248 Tier III 

Veg vigor- foliar 

application-in field

Garlon 3A Acceptable No Field Studyuseable 

information

* Pending the results of laboratory studies on individual bees (Tier 1), additional data may be requested to 

address exposure and effects at the colony level, per USEPA’s bee risk assessment guidance (USEPA 2014). 
52

Data Needed for Complete Assessment of Triclopyr Actives and Uses 

Guideline Number: 850.1300

Study Title: Chronic Toxicity to Freshwater Invertebrate using Triclopyr BEE technical

Rationale for Requiring the Data

Based on acute toxicity values to aquatic invertebrates, Triclopyr BEE is by far the most toxic 

form of the triclopyr active ingredients. Although BEE is expected to hydrolyze to triclopyr acid

in pH 7 water (t1/2 = 9 days), this time is considered sufficient to elicit chronic effects on 

aquatic invertebrates. Also, multiple applications are permitted on current labels. Therefore, 

since BEE is highly toxic to the water flea, Daphnia magna, and is expected to be transported 

directly to water via spray drift, a study is required to determine the chronic toxicity of BEE to 

freshwater aquatic invertebrates..

Practical Utility of the Data

How will the data be used? The data will be used to characterize the potential chronic risk for triclopyr 

BEE products.

How could the data change the Agency’s decision or impact the Agency’s future decision-making? 

The data could be used in quantitative risk assessment and thus may change the conclusions of 

that assessment. It could change the general conclusions of the qualitative characterization of 

risks to freshwater invertebrates, including endangered species.

Guideline Number: 850.1300

Study Title: Chronic Toxicity to Estuarine/Marine Invertebrate using Triclopyr BEE technical

Rationale for Requiring the Data

Based on acute toxicity values to aquatic invertebrates, Triclopyr BEE is by far the most toxic 

form of the triclopyr active ingredients. Although BEE is expected to degrade to triclopyr acid 

relatively rapidly (t1/2 < 9 days at pH 7), this time is considered sufficient to elicit chronic 

effects on aquatic invertebrates. Also, multiple applications are permitted on current labels. 

Based on acute toxicity values which classify the Butoxyethyl ester as highly toxic to the Grass 

shrimp, Palaemonetes pugio, uncertainties exist regarding the potential environmental exposure 

time for this active in higher pH marine water, and the use as a direct application near potentially 

sensitive estuarine aquatic habitats.

Practical Utility of the Data

How will the data be used? The data will be used to characterize the potential chronic risk for Triclopyr 

BEE products

How could the data change the Agency’s decision or impact the Agency’s future decision-making? 

The data could be used in quantitative risk assessment and thus may change the conclusions of 

that assessment. It could change the general conclusions of the qualitative characterization of 

risks to estuarine marine invertebrate crustacea.
53

Guideline Number 

Honeybee Larval Chronic Toxicity Testing with Triclopyr Acid technical

Rationale for Requiring the Data

The USEPA has recently developed guidance for assessing pesticide risks to bees (5).Based on 

the systemic mode of action of triclopyr products, potential to accumulate in pollen, extensive 

outdoor end uses use patterns, and expectation that the TEA and BEE products will eventually 

degrade to the Acid this study is requested. 

Practical Utility of the Data

How will the data be used? This data will be used to further characterize the risk to developing 

honeybees from the acid as an active and also as a major degradate when used in terrestrial 

environments such as forest lands, pastures, rights of way and commercial turf. 

How could the data change the Agency’s decision or impact the Agency’s future decision-making? 

The data could be used in quantitative risk assessment and thus may change the conclusions of 

that assessment. It could change the general conclusions of the qualitative characterization of 

acute risks to honeybee larvae from transport of triclopyr residues to the hive when used as 

currently labeled for vegetation control.

Guideline Number 

Honeybee Acute Oral Toxicity Testing with Triclopyr Acid technical

Rationale for Requiring the Data

Based on the systemic mode of action of triclopyr products, potential to accumulate in pollen, 

extensive outdoor end uses use patterns, and expectation that the TEA and BEE products will 

degrade to the Acid this study is requested with the technical acid.. 

Practical Utility of the Data

How will the data be used? This data will be used to further characterize the risk to honeybees 

from oral ingestion of the acid as an active and also as a major degradate when used in terrestrial 

environments such as forest lands, pastures, rights of way and commercial turf. 

How could the data change the Agency’s decision or impact the Agency’s future decision-making? 

The data could be used in quantitative risk assessment and thus may change the conclusions of 

that assessment. It could change the general conclusions of the qualitative characterization of 

acute risks to honeybee from oral ingestion of residues in pollen.

 

5

http://www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/terrestrial_biology_tech_team/GuidanceA

ssessingPesticideRisk2Bees.pdf 
54

Guideline Number 

Honeybee 10 Day Chronic Adult Oral Toxicity Testing with Triclopyr Acid technical

Rationale for Requiring the Data

The USEPA has recently developed guidance for assessing pesticide risks to bees. Based on the 

systemic mode of action of triclopyr products, potential to accumulate in pollen, extensive 

outdoor end uses use patterns, and expectation that the TEA and BEE products will degrade to 

the Acid this study is requested with the technical acid. 

Practical Utility of the Data

How will the data be used? This data will be used to further characterize the potential chronic risk 

to adult honeybees from the acid as an active and also as a major degradate when used in 

terrestrial environments such as forest lands, pastures, rights of way and commercial turf. 

How could the data change the Agency’s decision or impact the Agency’s future decision-making? 

The data could be used in quantitative risk assessment and thus may change the conclusions of 

that assessment. It could change the general conclusions of the qualitative characterization of 

chronic risks to honeybee adults from long term exposure to residues when used as currently 

labeled for vegetation control.

Guideline Number 850.2100

Avian Oral Toxicity test with passerine species using BEE technical

Rationale for Requiring the Data

A second species test for the Triclopyr BEE technical is requested based on outdoor end uses use 

patterns and expectation that acute exposure to BEE may occur and the somewhat greater acute 

toxicity of BEE vs. Triclopyr acid/TEA to birds. For outdoor uses FIFRA recommends that 

two species be tested. Therefore, an acute, oral study with a passerine species is requested.

Practical Utility of the Data

How will the data be used? This data will be used to further characterize the risk of the BEE as an 

active and also the Acid as a major degradate resulting from uses in terrestrial environments 

such as forest lands, pastures, rights of way and commercial turf.

How could the data change the Agency’s decision or impact the Agency’s future decision-making? 

The data could be used in quantitative risk assessment and thus may change the conclusions of 

that assessment. It could change the general conclusions of the qualitative characterization of 

acute risks to birds from ingestion of triclopyr when used at high rates currently permitted for 

turf uses.

11. References 

Below are some common references.... 

Jones, R.D. et al., 2000. Guidance for use of the Index Reservoir and Percent Crop Area Factor in 

Drinking Water Assessments (March 21, 2000). Office of Pesticide Programs, 

Environmental Fate and Effects Division, U.S. Environmental Protection Agency. 

Arlington, VA. 
55

USEPA. 1999. Guidance for Use of the Index Reservoir in Drinking Water Exposure 

Assessments. Arlington, VA. 

USEPA. 2000. Drinking Water Screening Level Assessment. Part A: Applying a Percent Crop 

Area Adjustment to Tier II Surface Water Model Estimates for Pesticide Drinking Water 

Exposure Assessments. FQPA Science Policy Document .Public Comment Draft 

September 1, 2000. Federal Register: October 11, 2000 (volume 65, number 197). 

Electronic copy available at http://www.epa.gov/pesticides/trac/science/ . 

USEPA. 2009. Guidance for Selecting Input Parameters in Modeling the Environmental Fate and 

Transport of Pesticides, Version 2.1. Office of Pesticide Programs, Environmental Fate 

and Effects Division, U.S. Environmental Protection Agency. Arlington, VA. 

U.S. EPA. 2012. Guidance for Residues of Concern in Ecological Risk Assessment. Office of 

Pesticide Programs, Environmental Fate and Effects Division, U.S. Environmental 

Protection Agency. Arlington, VA. 

U.S. EPA. 2003. Use of Regional Percent Crop Area Factors in Refined Drinking Water 

Assessments. US EPA Office of Pesticide Programs (OPP), Environmental Fate and 

Effects Division (EFED), Water Quality Technical Team (WQTT). Arlington, VA 

USEPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide 

Programs. United States Environmental Protection Agency (USEPA). Environmental 

Fate and Effects Division. Office of Pesticide Programs. Available at 

http://www.epa.gov/espp/consultation/ecorisk-overview.pdf. 

U.S. EPA. 2012. Approval of PRZM-GW for Use in Drinking Water Exposure Assessments. 

Office of Pesticide Programs, Environmental Fate and Effects Division, U.S. Environmental 

Protection Agency. Arlington, VA. 

U.S. EPA. 2014. Implementation of the Surface Water Concentration Calculator for Use in 

EFED. Office of Pesticide Programs, Environmental Fate and Effects Division, U.S. 

Environmental Protection Agency. Arlington, VA. 
56

Appendix A 

116001 (Triclopyr Acid) /116002 (Triclopyr TEA) /116004 (Triclopyr 

BEE) Fate-Chemistry Combined Bibliography 

161-1 Hydrolysis 

MRID Citation Reference

41879601 Cleveland, C.; Holbrook, D. (1991) A Hydrolysis Study of Triclopyr: Lab Project Number: 

ENV91023. Unpublished study prepared by DowElanco, North American Environ. Chem. 

Lab. 40 p. 

134174

Bidlack, H. (1978) The Hydrolysis of Triclopyr EB Ester in Buffered Deionized Water 

Natural Water and Selected Soils: GH-C 1106. (Unpublished study received Nov 13, 1979 

under 464-554; submit- ted by Dow Chemical U.S.A., Midland, MI; CDL:241362-A) 

161-2 Photodegradation-water 

MRID Citation Reference

41732201

Woodburn, K.; Batzer, F.; White, F.; et al. (1990) The Aqueous Photolysis of Triclopyr: 

Lab Project Number: GH-C 2434. Unpub- lished study prepared by DowElanco. 133 p. 

43007601 Havens, P.; Shepler, K. (1993) Photodegradation of (carbon 14)-Triclopyr Butoxyethyl 

Ester in a Buffered Aqueous Solution at pH 5 by Natural Sunlight: Lab Project Number: 

330W-1: 330W: ENV91090. Unpublished study prepared by PTRL West, Inc. and 

DowElanco, N. American Environmental Chem. Lab. 103 p. 

161-3 Photodegradation-soil 

MRID Citation Reference

41323501 Woodburn, K.; McGovern, P.; Shepler, K.; et al. (1989) Photodegra- dation of Triclopyr 

on Soil by Natural Sunlight: Project Number: GH/C/2250. Unpublished study prepared 

by Dow Chemical U.S.A. 85 p. 
57

44329901

Concha, M.; Kennard, L. (1997) Photodegradation of (2,6-(carbon 14))Triclopyr in/on 

Soil by Natural Sunlight: (Final Report): Lab Project Number: 647W-1: 647W: ENV 

97064. Unpublished study prepared by PTRL West, Inc. 110 p. 

162-1 Aerobic soil metabolism 

MRID Citation Reference

40346304

Acc 

229781

Laskowski, D.; Comeaux, L.; Bidlack, H. (1977) Aerobic Soil Decomposition of [carbon 

14]-Labeled 3,5,6-Trichloro-2-methopyridine: Laboratory ID: GHC-964. Unpublished study 

prepared by Dow Chemical. 50 p. 

43837501 Merritt, D. (1995) Aerobic Soil Metabolism of (carbon 14)-Triethylamine: Lab Project 

Number: ENV94074. Unpublished study prepared by DowElanco's North American 

Environmental Chemistry Lab. 126 p. 

47293801 Yoder, R. (2007) Degradation of Triclopyr BEE in Two US Soils under Aerobic Conditions. 

Project Number: 060080. Unpublished study prepared by Dow Agrosciences LLC. 56 p.

162-2 Anaerobic soil metab. 

MRID Citation Reference

151967 Laskowski, D.; Bidlack, H. (1984) Anaerobic Degradation of Triclo- pyr Butoxyethyl Ester: 

GH-C 1697. Unpublished study prepared by Dow Chemical U.S.A. 40 P. 

162-3 Anaerobic aquatic metabolism 

MRID Citation Reference

43837502 Wolt, J. (1995) Anaerobic Aquatic Metabolism of (carbon 14)-Triethylamine: Lab Project 

Number: ENV94086. Unpublished study prepared by DowElanco's North American 

Environmental Chemistry Lab. 102 p. 

151967 Laskowski, D.; Bidlack, H. (1984) Anaerobic Degradation of Triclopyr Butoxyethyl Ester: 

GH-C 1697. Unpublished study prepared by Dow Chemical U.S.A. 40 P.

162-4 Aerobic aquatic metabolism 

MRID Citation Reference
58

40479101 Cranor, W. and K.B. Woodburn (1987) Aerobic Aquatic Metabolism of ?Carbon 14|-

Triclopyr: 35651. Unpublished study prepared by Analytical Bio-Chemistry Laboratories, 

Inc. 48 p. 

43837503 Merritt, D. (1995) Aerobic Aquatic Metabolism of (carbon 14)-Triethylamine: Lab Project 

Number: ENV94073. Unpublished study prepared by DowElanco's North American 

Environmental Chemistry Lab. 100 p. 

163-1 Leaching/adsorption/desorption 

MRID Citation Reference

40749801 Woodburn, K.; Fontaine, D.; Richards, J. (1988) A Soil Adsorption/ Desorption Study of 

Triclopyr: Project ID: GHC-2017. Unpublish- ed study prepared by Dow Chemical U.S.A. 

62 p. 

164-1 Terrestrial field dissipation 

MRID Citation Reference

42730601 Buttler, I.; Roberts, L.; Siders, L.; et al. (1993) Non-Crop Right-of-Way Terrestrial 

Dissipation of Triclopyr in California: Lab Project Number: ENV91019. Unpublished study 

prepared by DowElanco and A&L Great Lakes Labs. 228 p. 

43033401 Petty, D.; Gardner, R. (1993) Right-Of-Way Terrestrial Dissipation of Triclopyr in North 

Carolina: Lab Project Number: ENV92049. Unpublished study prepared by DowElanco 

Chemistry Lab. 125 p.

43955901 Poletika, N.; Phillips, A. (1996) Field Dissipation of Triclopyr in Southern U.S. Rice 

Culture: Lab Project Number: ENV94015. Unpublished study prepared by A&L Great 

Lakes Laboratories, Inc.; North American Environmental Chemistry Laboratory, 

DowElanco; and Mid-South Weed Scientists, Inc. 429 p. 

164-2 Aquatic field dissipation 

MRID Citation Reference

41714305 Woodburn, K. (1989) The Aquatic Dissipation of Triclopyr in Banks Lake, Washington: 

Lab Project Number: GH-C 2211: 1645-87-0070. Unpublished study prepared by Dow 

Chemical U.S.A., Ricerca, Inc. and A&L Great Lakes Laboratories. 163 p. 

41714304 Woodburn, K. (1989) The Aquatic Dissipation of Triclopyr in Lake Seminole, Georgia: Lab 

Project Number: GH-C 2093. Unpublished study prepared by Dow Chemical U.S.A. 76 p. 

Actually TEA was applied, but degraded to acid.

44456102 Houtman, B.; Foster, D.; Getsinger, K. et al. (1997) Aquatic Dissipation of Triclopyr in 

Lake Minnetonka, Minnesota: Lab Project Number: ENV94001: CMXX-94-0380: 13939. 

Unpublished study prepared by DowElanco, Braun Intertec and The Dow Chemical Co. 527 

p. {OPPTS 860.1400} 
59

44456103 Foster, D.; Getsinger, K.; Petty, D. (1997) The Aquatic Dissipation of Triclopyr in a WholePond Treatment: Lab Project Number: ENV95012. Unpublished study prepared by 

DowElanco, ABC Labs. and A&L Great Lakes Lab. 306 p. {OPPTS 860.1400} 

44456104 Houtman, B.; Foster, D.; Getsinger, K. et al. (1997) Triclopyr Dissipation and the Formation 

and Decline of its TMP and TCP Metabolites in an Aquatic Environment: Lab Project 

Number: ENV96052: DE-05-96. Unpublished study prepared by DowElanco, A&L Great 

Lakes Labs., Inc. and Enviro-Bio-Tech, Ltd. 259 p. {OPPTS 860.1400} 

44198101 Phillips, A.; Poletika, N.; Lindsay, D. (1996) Frozen Storage Stability of 3,5,6-Trichloro-2-

Methoxypyridine in Soil Stored in Acetate Liners: Lab Project Number: ENV94015.01. 

Unpublished study prepared by DowElanco. 44 p.

164-3 Forest field dissipation 

MRID Citation Reference

44039301 Gardner, R. (1996) Response to EPA Review of Triclopyr Terrestrial and Forestry Field 

Dissipation Studies: "Non-Crop Right-of-way Terrestrial Dissipation of Triclopyr in 

California:" MRID 42730601: and "The Dissipation and Movement of Triclopyr in a 

Northern USA Forest System:" MRID 43011601: Lab Project Number: GH-C 4074: 

RES94045/RES94046/RES94154. Unpublished study prepared by DowElanco's Global 

Environmental Chemistry Lab. 22 p. 

43011601 Cryer, S.; Cooley, T.; Schuster, L. et al. (1993) The Dissipation and Movement of Triclopyr 

in a Northern USA Forest Site Preparation Ecosystem: Lab Project Number: ENV91087: 

PM91-2502. Unpublished study prepared by Pan-Agricultural Labs, Inc. 555 p. 

92189037 Fontaine, D. (1990) Dow Chemical U S A Phase 3 Summary of MRID 41445001. 

41445001 Fontaine, D. (1990) Dow Chemical U S A Dispersal and Degradation of Triclopyr within a 

Canadian Boreal Forest Ecosystem following an Aerial Application of Garlon 4: Project ID. 

GH-C2314. Prepared by DOW CHEMICAL U S A. 12 p.

92189038 Havens, P. (1990) Dow Chemical U S A Phase 3 Summary of MRID 41353201. 

Determination of Residues in a Forest Ecosystem Resulting from the Aerial Application of 

Garlon 4 Herbicide: Project ID: GH-C2283. Prepared by DOWELANCO. 15 p. 

44039301 Gardner, R. (1996) Response to EPA Review of Triclopyr Terrestrial and Forestry Field 

Dissipation Studies: "Non-Crop Right-of-way Terrestrial Dissipation of Triclopyr in 

California:" MRID 42730601: and "The Dissipation and Movement of Triclopyr in a 

Northern USA Forest System:" MRID 43011601: Lab Project Number: GH-C 4074: 

RES94045/RES94046/RES94154. Unpublished study prepared by DowElanco's Global 

Environmental Chemistry Lab. 22 p.

44039302 Havens, P. (1995) Response to EPA Review EFGWB#92-0111: "Dispersal and Degradation 

of Triclopyr within a Canadian Boreal Forest Ecosystem Following an Aerial Application of 

Garlon 4:" MRID 41445001: Lab Project Number: GH-C 2314A. Unpublished study 

prepared by DowElanco Environmental Fate Lab. 15 p. 

165-4 Bioaccumulation in fish 

MRID Citation Reference
60

44015101 Rick, D.; Kirk, H.; Fontaine, D.; et al. (1996) The Nature of Triclopyr Residues in the 

Bluegill, Lepomis macrochirus Rafinesque: Lab Project Number: DECO-ES-2761. 

Unpublished study prepared by The Dow Chemical Co. 64 p. 

42090415 Woodburn, K. (1991) Response to Phase 3 Submission on Triethyl- ammonium 

Triclopyr...?Bioaccumulation in Fish|. Unpublished study prepared by Dow Chemical Co., 

Environmental Tox & Chem Res. Lab. 11 p. 

Analytical Methods 

44456105 Olberding, E. (1997) Validation Report for the Determination of Residues of Triclopyr, 

3,5,6-Trichloro-2-pyridinol, and 2-Methoxy-3,5,6-trichloropyridine in Water by Capillary 

Gas Chromatography with Mass Selective Detection: Lab Project Number: RES94075: 

GRM 95.18. Unpublished study prepared by DowElanco. 58 p. 

44456106 Young, D.; Mihaliak, C. (1997) Validation Report for the Determination of Residues of 

Triclopyr and Trichloropyridinol in Water by Immunoassay: Lab Project Number: 

RES94069: GRM 95. 11. Unpublished study prepared by DowElanco. 50 p. {OPPTS 

850.7100} 

44456109 Harris, E. (1997) Independent Laboratory Validation of Method GRM 95.18--

Determination of Residues of Triclopyr, 3,5,6-Trichloro-2-pyridinol, and 2-Methoxy-3,5,6-

trichloropyridine in Water by Capillary Gas Chromatography with Mass Selective 

Detection: Lab Project Number: QMAP97002: GRM 95.18. Unpublished study prepared 

by Quality Management and Analytical Services, Inc. and DowElanco. 93 p. {OPPTS 

850.7100} 

44456110 Emery, M. (1997) Independent Laboratory Validation of Method GRM 95.11--

Determination of Residues of Triclopyr and Trichloropyridinol in Water Using Magnetic 

Particle-Based Immunoassay Test Kits: Lab Project Number: 06-9708I: GRM 95. 11: 

RES94069. Unpublished study prepared by Minnesota Valley Testing Labs., Inc (MVTL) 

and DowElanco. 65 p. {OPPTS 850.7100} 

44456111 Frederick, P. (1997) Independent Laboratory Validation of Method GRM 95.19--

Determination of Residues of Triclopyr, 3,5,6-Trichloro-2-pyridinol, and 2-Methoxy-3,5,6-

trichloropyridine in Sediment and Soil by Capillary Gas Chromatography with Mass 

Selective Detection: Lab Project Number: CSA05287: GRM 95.19. Unpublished study 

prepared by Central States Analytical and DowElanco. 117 p. {OPPTS 850.7100} 

44456107 Olberding, E.; Foster, D.; McNett, D. (1997) Validation Report for the Determination of 

Residues of Triclopyr, 3,5,6-Trichloro-2-pyridinol, and 2-Methoxy-3,5,6-trichloropyridine 

in Sediment and Soil by Capillary Gas Chromatography with Mass Selective Detection: 

Lab Project Number: RES94145: GRM 95.19. Unpublished study prepared by DowElanco 

and The Dow Chemical Co. 68 p. 

Other 

Studies 

The following fate studies (2-butoxyethanol and TCP) are not listed in the 

bibliography of Trichlopyr. They were submitted to other chemicals.

43799101 Batzer, F.R. 1995. Aerobic Soil metabolism of 14C-2-Butoxyethanol. Laboratory Study 

ID ENV94094. Unpublished study performed and submitted by DowElanco, Indianapolis, 

IN. (Submitted to 2,4-D, butoxyethyl ester; PC Code 030052) 
61

43799103 Batzer, F. (1995) Anaerobic Aquatic Metabolism of (Carbon 14)-2- Butoxyethanol: Lab 

Project Number: ENV94096. Unpublished study prepared by DowElanco North American 

Environmental Chemistry Lab. 88 p. (Submitted to 2,4-D, butoxyethyl ester; PC Code 

030052)

43799106 Batzer, F. (1995) Aerobic Aquatic Metabolism of (Carbon 14)-2- Butoxyethanol: Lab 

Project Number: ENV94096. Unpublished study prepared by DowElanco North American 

Environmental Chemistry Lab. 88 p. (Submitted to 2,4-D, butoxyethyl ester; PC Code 

030052)

43509201 Shepler, K.; Racke, K.; Concha, M. (1994) Photodegradation of 3,5,6-Trichloro-2-

Pyridinol on Soil by Natural Sunlight: Lab Project Numbers: 455W-1: 455W: ENV94027. 

Unpublished study prepared by PTRL West, Inc. 101 p. (Submitted to PC Code 206900 

(2(1H)-pyridinon, 3,5,6-trichloro)) 

42144912

Cranor, W. (1990) Aerobic Soil Metabolism of ?carbon 14| TCP: Lab Project Number: 

36641. Unpublished study prepared by Analytical Bio-Chemistry Labs, Inc. 44 p. 

(Submitted to PC Code 059101 (chlorpyrifos))

42493901 Racke, K.; Lubinski, R. (1992) Sorption of 3,5,6-Trichloro-2-Pyridinol in Four Soils: Lab 

Project Number: ENV91081. Unpublished study prepared by DowElnco. 44 p. (Submitted 

to PC Code 059101 (chlorpyrifos) and PC Code 206900 (2(1H)-pyridinon, 3,5,6-

trichloro))
62

Eco Effects Bibliographies 

PC Codes 116001, 116002, 116004, 2069000- Triclopyr Acid, TEA, BEE and TCP 

degradate Combined 

Ecoeffects 

71-1 850.2100 Avian Single Dose Oral Toxicity 

MRID Citation Reference

Triclopyr Acid studies

40346401 Wildlife International Ltd. (1976) Acute Oral LD50--Mallard Duck Triclopyr 

Technical Final Report: Project No. 103-156. Unpublished study. 11 p. 

TEA Salt studies

134178 Fink, R.; Beavers, J.; Brown, R. (1978) Acute Oral LD50--Mallard Duck: Triclopyrethylene Glycol Butyl Ether Ester: Project No. 103-175. Final rept. (Unpublished 

study received Nov 13, 1979 under 464-554; prepared by Wildlife International Ltd. 

and Washington College, submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:241360-B) PDF 2045559

40346501 Wildlife International Ltd. (1978) Acute Oral LD50--Mallard Duck TriclopyrTriethylamine Salt: Final Report: Project No. 103-174. Unpublished study. 14 p. 

Triclopyr TEA salt= 116002 PDF 2045568

Triclopyr BEE Studies

41902001 Ormand, J.; Bell, C. (1991) Triclopyr Bee: Stability in Prepared Game Bird Starter 

Ration: Lab Project Number: ES-DR-0133-7242-6. Unpublished study prepared by 

Dow Chemical Co. 14 p. Stability in feed see 4192002-2003

41902002 Campbell,S.; Lynn,S. (1991) Triclopyr Bee: An Acute Oral Toxicity Study With the 

Northern Bobwhite: Lab Project Number: ES-DR- 0133-7242-9. Unpublished study 

prepared by Dow Chemical Co. 25 p. 2022125

41902003 Campbell,S.; Lynn,S. (1991) Garlon 4 Herbicide: An Acute Oral Toxicity Study With 

the Northern Bobwhite: Lab Project Number: ES- DR-0224-6186-8. Unpublished 

study prepared by Wildlife International LTD. 22 p. Garlon 4 is Triclopyr BEE. 

2022102

71-2 850.2200 Avian Dietary Toxicity 

MRID Citation Reference

Triclopyr Acid studies

31249 or 134177 Beavers, J.B.; Fink, R.; Brown, R.; et al. (1979) Final Report: Eight-Day Dietary 

LC50--Mallard Duck: Project No. 103-193. (Un- published study received Apr 29, 

1980 under 464-546; prepared by Wildlife International, Ltd. in cooperation with 

Washington College, submitted by Dow Chemical U.S.A., Midland, Mich.; CDL: 

242368-B) 2035109
63

40346403 Wildlife International Ltd. (1976) Eight Day Dietary LC50--Bobwhite Quail 

Triclopyr Technical Final Report: Project No. 103-155. Unpublished study. 11 p. 

Triclopyr TEA Salt Studies

40346502 Wildlife International Ltd. (1977) Eight-day Dietary LC50-Mallard Duck, TriclopyrTriethylamine Salt: Final Report: Project No. 103-171. Unpublished study. 13 p. 

2045569

40346503 Wildlife International Ltd. (1977) Eight-day Dietary LC50-Bobwhite quail TriclopyrTriethylamine Salt: Final Report: Project No. 103-170. Unpublished study. 14 p. 

2045570

42090404 Mayes, M. (1991) Response to Phase 3 Submission on Triethylammonium 

Triclopyr.... ?Acute Avian Dietary LC50 Test--Quail|: Lab Project Number: GHRC 

130. Unpublished study prepared by Dow Chemical Co., Tox & Chem Res. Lab. 4 p. 

Study response for project GHRC 130.

Triclopyr BEE Studies

41905501 Lynn, G.; Smith, G.; Grimes, J. (1991) Triclopyr Bee: A Dietary LC50 Study with the 

Northern Bobwhite: Lab Project Number: ES-DR-0133-7242-10. Unpublished study 

prepared by Wildlife International LTD. 22 p. PDF 2022122

41905502 Lynn, S.; Smith, G.; Grimes, J. (1991) Triclopyr Bee: A Dietary LC50 Study With the 

Mallard: Lab Project No: ES-DR-0133-7242-11. Unpublished study prepared by 

Wildlife International LTD. 21 p. PDF 2022122

134179 Fink, R.; Beavers, J.; Brown, R. (1977) Eight-day Dietary LC50-- Mallard Duck: 

Triclopyr-ethylene Glycol Butyl Ether Ester: Project No. 103-173. Final rept. 

(Unpublished study received Nov 13, 1979 under 464-554; prepared by Wildlife 

International Ltd. and Washington College, submitted by Dow Chemical U.S.A., 

Mid- land, MI; CDL:241360-C) PDF 2022124

134180 Fink, R.; Beavers, J.; Brown, R. (1978) Eight-day Dietary LC50-- Bobwhite Quail: 

Triclopyr-ethylene Glycol Butyl Ether Ester: Project No. 103-172. Final rept. 

(unpublished study received Nov 13, 1979 under 464-554; prepared by Wildlife 

International Ltd. and Washington College, submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:241360-D) PDF 2022123 

71-4 850.2300 Avian Reproduction 

MRID Citation Reference

Triclopyr Acid

31250

DOWCO 

233

Beavers, J.B.; Fink, R.; Grimes, J.; et al. (1980) Final Report: One-Generation Reproduction 

Study--Mallard Duck: Project No. 103-192. (Unpublished study received Apr 29, 1980 

under 464-546; prepared by Wildlife International, Ltd., submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:242368-C) PDF 2035112

31251

DOWCO 

233

Beavers, J.B.; Fink, R.; Grimes, J.; et al. (1979) Final Report: One-Generation Reproduction 

Study--Bobwhite Quail: Project No. 103-191. (Unpublished study received Apr 29, 1980 
64

under 434-546; prepared by Wildlife International, Ltd., submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:242368-D) PDFs 2035110 2035111

92189005 Mayes, M. (1990) Dow Chemical U S A Phase 3 Summary of MRID 00031251. Onegeneration Reproduction Study - Bobwhite Quail: Dowco 233; Final Report: Project ID: 

103-191. Prepared by Wildlife International Ltd.. 13 p. 

92189006 Mayes, M. (1990) Dow Chemical U S A Phase 3 Summary of MRID 00031250. Onegeneration Reproduction Study - Mallard Duck Dowco 233; Final Report: Project ID: 103-

174. Prepared by Wildlife International Ltd.. 14 p. 

Triclopyr TEA Salt Studies

42090406 Mayes, M. (1991) Response to Phase 3 Submission on Triethylammonium Triclopyr.... 

?Avian Reproduction Test--Mallard|: Lab Project Number: GHRC 161. Unpublished study 

prepared by Dow Chemical Co., Environmental Tox & Chem Res. Lab. 39 p. DOW 

Response

72-1 850.1075 Acute Toxicity to Freshwater Fish 

MRID Citation Reference

Triclopyr Acid studies

62622

(found in 

116002)

Batchelder, T.L. (1973) Acute Fish Toxicity of Dowco 233 ... and Two Derivatives. 

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44585404 Wan, M.; Moul, D.; Watts, R. (1987) Acute toxicity to juvenile pacific salmonids of 

Garlon 3A, Garlon 4, triclopyr, triclopyr ester, and their transformation products: 

3,5,6-trichloro-2-pyridinol and 2-methoxy-3,5,6-trichloropyridine. Bulletin of 

Environmental Contamination and Toxicology 39:721-728. Open lit ECOTOX 

reference 12605

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151956

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42090408 

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151958 Mayes, M.; Dill, D.; Mandoza, C.; et al. (1983) The Acute and Chronic Toxicity of 

Triclopyr (...) Triethylamine Salt Solution to Fathead Minnows (...): ES-582. 

Unpublished study prepared by Environmental Sciences Research, Dow Chemical 

U.S.A. 18 p. PDF 2045561

151964 Batchelder, T. (1975) Environmental Analysis and Special Fish Toxi- cities of Two 

Triclopyr Formulations. Unpublished study pre- pared by Dow Chemical Co. 20 p. 

41714301 Barron, M.; Ball, T. (1989) Garlon 3A Herbicide: Evaluation of the Toxicity to the 

Channel Catfish (Ictalurus punctatus): Lab Pro- ject Number: ES-DR-0121-6064-8: 

ES-2097. Unpublished study pre- pared by The Dow Chemical Co. 15 p. PDF 

2045578
65

44585404 Wan, M.; Moul, D.; Watts, R. (1987) Acute toxicity to juvenile pacific salmonids of 

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3,5,6-trichloro-2-pyridinol and 2-methoxy-3,5,6-trichloropyridine. Bulletin of 

Environmental Contamination and Toxicology 39:721-728. OPEN LIT

92189007 Mayes, M. (1990) Dow Chemical U S A Phase 3 Summary of MRID 00151956. 

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92189008 Mayes, M. (1990) Dow Chemical U S A Phase 3 Summary of MRID 00151956. 

Toxicity of Triclopyr, Triethylamine Salt to Freshwater Organisms: Project ID. ES199. Prepared by DOW CHEMICAL U S A 10 p. Registrant summary

48939402 Wemhoner, U. (2006) GF-1883 - Acute Toxicity to Rainbow Trout (Oncorhynchus 

mykiss) Under Flow-Through Conditions. Project Number: 060394/OCR, 

1072/010/108. Unpublished study prepared by Springborn Smithers Laboratories 

(Europe). 55p. Triclopyr TEA + Aminopyralid TIPA salt- 005209 In Review

Triclopyr BEE Studies

151962

ACC 259512

Ross, D.; Pell, I. (1981) The Acute Toxicity of Garlon 4E to Rain- bow Trout (...): 

Report No. DWC 336 (a)/81750. Unpublished study prepared by Huntingdon 

Research Centre. 15 p. 

151963

ACC 259512

Milazzo, D.; Batchelder, T. (1981) Evaluation of Garlon 4 Formu- lation in the 

Aquatic Environment: Report No. ES-426. Unpub- lished study prepared by Dow 

Chemical U.S.A. 21 p. PDF 2022115

151965 Milazzo, D.; Batchelder, T. (1981) Environmental Screening of Chemicals: Garlon 4 

Triclopyr EB Ester: Report No. ES-427. Un- published study prepared by Dow 

Chemical U.S.A. 26 p. PDF 2022115

41714302 McCall, P. (1987) Simulation of the Aquatic Fate of Triclopyr Butoxyethyl Ester and 

Its Expected Impact on Aquatic Species: Lab Project Number: GH-C 1916. 

Unpublished study prepared by Dow Chemical Co. U.S.A. 30 p. PDF 2022099

41928901 Gorzinski, S.; Lehr, K.; Piasecki, D. et al (1991) Triclopyr Bee: Static Acute 96-Hour 

Toxicity to the Bluegill, Lepomis macrochirus Rafinesque: Lab Project Number: ESDR-0133-7242-8. Unpublished study prepared by Dow Chemical Co. 35 p. PDF 

2022106

41928902 Gorzinski, S.; Lehr, K.; Piasecki, D. et al. (1991) Triclopyr Bee: Static Acute 96-Hour 

Toxicity to the Rainbow Trout, Oncorhynchus mykiss Walbaum: Lab Project 

Number: ES-DR-0133-7242-7. Unpublished study prepared by Dow Chemical Co. 33 

p. PDF 2022107

41971603 Gorzinski, S.; Lehr, K.; Piasecki, D.; et al. (1991) Garlon 4 Herbicide: Static Acute 

96-Hour Toxicity to the Rainbow Trout, Oncorhynchus mykiss Walbaum: Lab 

Project Number: ES-DR-022406168-4. Unpublished study prepared by DowElanco. 

33 p. PDF 2022114

41971604 Gorzinski, S.; Lehr, K.; Piasecki, D.; et al. (1991) Garlon 4 Herbicide: Static Acute 

96-Hour Toxicity to the Bluegill, Lepomis macrochirus Rafinesque: Lab Project 

Number: ES-DR-022406186-3. Unpublished study prepared by DowElanco. 33 p. 

PDF 2022113

42884501 Woodburn, K.; Rick, D.; Kirk, H. (1993) Triclopyr Bee: Acute 96-Hour FlowThrough Toxicity to the Rainbow Trout, Oncorhynchus mykiss Walbaum: Lab 

Project Number: DECO-ES-2619. Unpublished study prepared by The Environmental 

Toxicology & Chemistry Research Lab., Dow Chemical Co. 31 p. PDF 2022126
66

42917901 Woodburn, K.; Hugo, J.; Kirk, H. (1993) Triclopyr BEE: Acute 96-Hour FlowThrough Toxicity to the Bluegill, Lepomis macrochirus Rafinesque: Lab Project 

Number: DECO-ES-2620. Unpublished study prepared by The Environmental 

Toxicology & Chemistry Research Lab. 31 p. PDF 2022127

43442601 Weinberg, J.; Hugo, J.; Miller, J. (1994) Evaluation of the Acute Toxicity of Garlon 4 

Herbicide to the Bluegill, Lepomis macrochirus Rafinesque: Lab Project Number: 

DECO-ES-2854. Unpublished study prepared by The Dow Chemical Co. 25 p. PDF 

2022131

43442602 Weinberg, J.; Hugo, J.; Miller, J. (1994) Evaluation of the Acute Toxicity of Garlon 4 

Herbicide to the Rainbow Trout, Oncorhynchus mykiss Walbaum: Lab Project 

Number: DECO-ES-2853. Unpublished study prepared by The Dow Chemical Co. 25 

p. PDF 2022130

134181

ACC 259511

McCarty, W.; Alexander, H. (1978) Toxicity of Triclopyr, Ethylene Glycol Butyl 

Ether Ester to Freshwater Organisms. (Unpublished study received Nov 13, 1979 

under 464-554; submitted by Dow Chemical U.S.A., Midland, MI; CDL:241360-E) 

41971603 Gorzinski, S.; Lehr, K.; Piasecki, D.; et al. (1991) Garlon 4 Herbicide: Static Acute 

96-Hour Toxicity to the Rainbow Trout, Oncorhynchus mykiss Walbaum: Lab 

Project Number: ES-DR-022406168-4. Unpublished study prepared by DowElanco. 

33 p. PDF 2022214

41971604 Gorzinski, S.; Lehr, K.; Piasecki, D.; et al. (1991) Garlon 4 Herbicide: Static Acute 

96-Hour Toxicity to the Bluegill, Lepomis macrochirus Rafinesque: Lab Project 

Number: ES-DR-022406186-3. Unpublished study prepared by DowElanco. 33 p. 

PDF 2022113

44585404 Wan, M.; Moul, D.; Watts, R. (1987) Acute toxicity to juvenile pacific salmonids of 

Garlon 3A, Garlon 4, triclopyr, triclopyr ester, and their transformation products: 

3,5,6-trichloro-2-pyridinol and 2-methoxy-3,5,6-trichloropyridine. Bulletin of 

Environmental Contamination and Toxicology 39:721-728. OPEN LIT

TCP Degradate Studies

44585404 Wan, M.; Moul, D.; Watts, R. (1987) Acute toxicity to juvenile pacific salmonid of 

Garlon 3A, Garlon 4, triclopyr, triclopyr ester, and their transformation products: 

3,5,6-trichloro-2-pyridinol and 2-methoxy-3,5,6-trichloropyridine. Bulletin of 

Environmental Contamination and Toxicology 39:721-728. Open Lit

72-2 850.1010 Acute Toxicity to Freshwater Invertebrates 

MRID Citation Reference

Triclopyr Acid studies

40346405 Batchelder, T.; McCarty, W. (1977) Static Acute Toxicity of Triclopyr to Daphnia 

magna, Letter Report ES-37L, Enviromental (sic) Sciences Research. Unpublished 

study prepared by Dow Chemical Co. 3 p. Letter re 403465804

40346504

(Found in 

116002)

McCarty, W.; Batchelder, T. (1977) Toxicity of Triclopyr to Daphnids. 

Environmental Sciences Research,, DOW Chemical. Unpublished study prepared by 

Dow Chemical. 8 p. ACC 234248 PDF 2035114

Triclopyr TEA Salt Studies
67

151956 McCarty, W.; Alexander, H. (1978) Toxicity of Triclopyr, Triethyl- amine Salt to 

Freshwater Organisms: ES-199. Unpublished study prepared by Environmental 

Research Lab., Dow Chemical U.S.A. 14 p. PDF 2045560

151959 Gersich, F.; Mandoza, C.; Hopkins, D.; et al. (1982) The Acute and Chronic 

Toxicity of Triclopyr (...) Triethylamine Salt Solution to Daphnia magna Straus: 

ES-583. Unpublished study prepared by Environmental Sciences Research, Dow 

Chemical U.S.A. 19 p. PDF 2045562

151960 Gersich, F.; Hopkins, D.; Milazzo, D. (1985) The Development of Flow-through 

Acute and Chronic Test Methods for Daphnia magna Straus: ES-756. Unpublished 

study prepared by Dow Chemical U.S.A. 20 p. Test Methods

41736301 Barron, M.; Mayes, M.; Ball, T. (1989) Garlon 3A Herbicide Evaluation of The 

Toxicity to The Crayfish: Lab Project Number: ES-DR- 0121-6064-78. Unpublished 

study prepared by The Dow Chemical Co. 15 p. PDF 2045580

92189009 Mayes, M. (1990) Dow Chemical U S A Phase 3 Summary of MRID 00151956. 

Toxicity of Triclopyr, Triethylamine Salt to Freshwater Organisms: Project ID: ES199. Prepared by Dow Chemical Co.. 10 p. 

42090409 Mayes, M. (1991) Response to Phase 3 Submission on Triethylammonium 

Triclopyr... ?Acute Toxicity Test for Freshwater Invertebrate|: Lab Project Number: 

ES-199. Unpublished study prepared by Dow Chemical Co., Environmental Tox & 

Chem Res. Lab. 7 p. 

Triclopyr BEE Studies

151963 Milazzo, D.; Batchelder, T. (1981) Evaluation of Garlon 4 Formulation in the Aquatic 

Environment: Report No. ES-426. Unpublished study prepared by Dow Chemical 

U.S.A. 21 p. PDF 2022116

151965

ACC 259512

Milazzo, D.; Batchelder, T. (1981) Environmental Screening of Chemicals: Garlon 4 

Triclopyr EB Ester: Report No. ES-427. Un- published study prepared by Dow 

Chemical U.S.A. 26 p. PDF 2022115

43442603 Weinberg, J.; Hugo, J.; Massaro, L. et al. (1994) Evaluation of the Acute Toxicity of 

Garlon 4 Herbicide to the Daphnid, Daphnia magna Straus: Lab Project Number: 

DECO-ES-2855. Unpublished study prepared by The Dow Chemical Co. 25 p. PDF 

2022129

72-3 850.1025, 850.1035, or 850.1075 

Acute Toxicity to Estuarine/Marine Organisms 

MRID Citation Reference

Triclopyr Acid studies

None submitted

Triclopyr TEA Salt Studies

62623 or 

40346406

Heitmuller, T. (1975) Acute Toxicity of M-3724 to Larvae of the Eastern Oyster 

(Crassostrea virginica), Pink Shrimp (Penaeus duorarum), and Fiddler Crabs (Uca 

pugilator). (Unpublished study received Nov 4, 1975 under 464-EX-46; pre- pared by 
68

Bionomics, EG&G, Inc., submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:233134-H) PDF 2045563

40346406 Bionomics--EG&G, Inc. (1975) Acute Toxicity of M-3724 to Larvae of the Eastern 

Oyster (Crassostrea virginica), Pink Shrimp (Penaeus duorarum), and Fiddler Crabs 

(UCA pugilator). Unpublished study. 11 p. PDFs 2045563, 2045564, 2045565, 

2045566

41633703 Ward, T.; Boeri, R. (1989) Acute Flow-through Toxicity of Triclopyr TEA Sala to the 

Tidewater Silverside, Menidia beryllina: Lab Project Number: 8990/D. Unpublished 

study prepared by Resource Analysts, Inc. 26 p. PDF 2045571

42646101 Ward, T.; Kowalski, P.; Boeri, R. (1993) Acute Flow-Through Mollusc Shell 

Deposition Test with Triclopyr TEA Salt: Lab Project Number: 51-DO: ES-2498. 

Unpublished study prepared by T. R. Wilbury Labs., Inc. 24 p. PDF 2045584

42646102 Ward, T.; Kowalski, P.; Boeri, R. (1992) Acute Toxicity of Triclopyr TEA Salt to the 

Grass Shrimp, Palaemonetes pugio: Lab Project Number: 50-DO: ES-2497. 

Unpublished study prepared by T. R. Wilbury Labs., Inc. 25 p. PDF 2045585

Triclopyr BEE Studies

41971601 Ward, T.; Boeri, R. (1991) Triclopyr Bee: Acute Flow-Through Toxic- ity to the 

Grass Shrimp, palaemonetes pugio: Lab Project Number: ES-DR-0133-7242-12. 

Unpublished study prepared by Resource Ana- lysts, Inc. 27 p. PDF 2022109

41971602 Ward, T.; Boeri, R. (1991) Triclopyr Bee: Acute Flow-Through Shell Deposition Test 

with the Eastern Oyster, Crassostrea virginica: Lab Project Number: ES-DR-0133-

7242-14. Unpublished study prep- ared by Resource Analysts, Inc. 25 p. PDF 

2022110

41969901 Ward, T.; Boeri, R. (1991) Garlon 4 Herbicide: Acute Flow-through Toxicity to the 

Tidewater Silverside, Menidia beryllina: Lab Project Number: ES-DR-0224-6186-6. 

Unpublished study prepared by Resource Analysts, Inc. 26 p. PDF 2022105

41969902 Ward, T.; Boeri, R. (1991) Garlon 4 Herbicide: Acute Flow-through Toxicity to Grass 

Shrimp, pugio: Lab Project No: ES-DR-0224- 6186. Unpublished study prepared by 

Resource Analysts, Inc. 27 p. PDF 2022108

42948001 Alexander, H. (1993) Supplemental to MRID No. 41969902--Garlon 4 Herbicide: 

Acute Flow-through Toxicity to Grass Shrimp Palaemonetes pugio: Lab Project 

Number: MWM093093. Unpublished study prepared by Dow Chemical Co., 

Environmental Tox. & Chem. Research Lab and DowElanco. 14 p. Supplement

41969903 Ward, T.; Boeri, R. (1991) Garlon 4 Herbicide: Acute Flow-through Shell Deposition 

Test with the Eastern Oyster, Crassostrea virginica: Lab Project Number: ES-DR0224-6186-7. Unpublished study prepared by Resource Analysts, Inc. 26 p. PDF 

2022111

41971601 Ward, T.; Boeri, R. (1991) Triclopyr Bee: Acute Flow-Through Toxic- ity to the 

Grass Shrimp, palaemonetes pugio: Lab Project Number: ES-DR-0133-7242-12. 

Unpublished study prepared by Resource Ana- lysts, Inc. 27 p. PDF 2022109

41971602 Ward, T.; Boeri, R. (1991) Triclopyr Bee: Acute Flow-Through Shell Deposition Test 

with the Eastern Oyster, Crassostrea virginica: Lab Project Number: ES-DR-0133-

7242-14. Unpublished study prep- ared by Resource Analysts, Inc. 25 p. PDF 

2022110

42053901 Ward, T.; Boeri, R. (1991) Triclopyr BEE: Acute Flow-Through Toxic- ity to the 

Tidewater Silverside, Menidia beryllina: Lab Project Number: ES-DR-0133-7242-13. 
69

Unpublished study prepared by EnviroSystems Division & Resource Analysts, Inc. 

26 p. PDF 2022121

TCP Degradate

42245901 Graves, W.; Smith, G. (1991) 3,5,6-Trichloro-2-Pyridinol: A 96-Hour Flow-through 

Acute Toxicity Test with the Atlantic Silverside (Menidia menidia): Amended 

Report: Lab Project Number: 103A-101A: ES-DR-0037-0423-9. Unpublished study 

prepared by Wildlife International Ltd. 48 p Amended report 2066446 in PC 

059101

72-4 850.1400 850.1300 

Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study 

MRID Citation Reference

Triclopyr Acid

No Data

Triclopyr TEA Salt Studies

46269 Swabey, Y.H.; Schenk, C.F. (1963) Report on Algicides and Aquatic Herbicides. 

(Ontario, Water Resources Commission, Laboratory Division, Biology Branch, 

unpublished study; CDL:107773-B) 

49637

ACC 259511 and 

259512

Batchelder, T.L. (1973) Acute Fish Toxicity of Dowco 233 (3,5,6- Trichloro-2-

pyridyloxyacetic acid) and Two Derivatives ?sic|: Report WCL--73014. (Unpublished 

study received Feb 26, 1974 under unknown admin. no.; submitted by Dow Chemical 

U.S.A.; Midland, Mich.; CDL:222240-E) PDF 2045521 pg 11

151958 Mayes, M.; Dill, D.; Mandoza, C.; et al. (1983) The Acute and Chronic Toxicity of 

Triclopyr (...) Triethylamine Salt Solution to Fathead Minnows (...): ES-582. 

Unpublished study prepared by Environmental Sciences Research, Dow Chemical 

U.S.A. 18 p. ACC 259511 PDF 2045561

151959 Gersich, F.; Mandoza, C.; Hopkins, D.; et al. (1982) The Acute and Chronic Toxicity 

of Triclopyr (...) Triethylamine Salt Solution to Daphnia magna Straus: ES-583. 

Unpublished study prepared by Environmental Sciences Research, Dow Chemical 

U.S.A. 19 p. ACC 259511 PDF 2045562

151960

ACC 259511

Gersich, F.; Hopkins, D.; Milazzo, D. (1985) The Development of Flow-through 

Acute and Chronic Test Methods for Daphnia magna Straus: ES-756. Unpublished 

study prepared by Dow Chemical U.S.A. 20 p. Methods development

42090410 Mayes, M. (1991) Response to Phase 3 Submssion on Triethylammonium 

Triclopyr...?Fish Early Life-Stage Test--Fathead Minnow|: Lab Project Number: ES582. Unpublished study prepared by Dow Chemical Co., Environmental Tox and 

Chem Res. Lab. 45 p. 

42090411 Mayes, M. (1991) Response to Phase 3 Submission on Triethylammonium 

Trichlopyr...?Invertebrate Life-Cycle Test (Daphnia)|: Lab Project Number: ES-583. 
70

Unpublished study prepared by Dow Chemical Co., Environmental Tox & Chem 

Research Lab. 18 p. 

43230201 Weinberg, J.; Hugo, J.; Martin, M.; et al. (1994) Evaluation of the Toxicity of 

Triclopyr Butoxyethyl Ester to the Early Life Stages of the Rainbow Trout, 

Oncorhynchus mykiss Walbaum: Lab Project Number: DR/0133/7242: 

DECO/ES/2699. Unpublished study prepared by The Environmental Toxicology & 

Chemistry Research Lab. 47 p. PDF 2022128

41736304 Barron, M.; Mayes, M.; Murphy, P.; et al. (1989) Pharmacokinetics And Metabolism 

of Triclopyr Butoxyethyl Ester In Coho Salmon: Lab Project Number: ES-DR-0133-

7242-5: ES-1082. Unpublished Study prepared by The Dow Chemical Co. 31 p. 

TCP Degradate Studies

44997301

(found in 

116002) 

Marino, T.; Gilles, M.; Rick, D. et al. (1999) Evaluation of the Toxicity of 3,5,6-

Trichloro-2-Pyridinol (TCP) to the Early Life Stages of the Rainbow Trout, 

Oncorhynchus mykiss Walbaum: Lab Project Number: 991173. Unpublished study 

prepared by The Dow Chemical Co. 56 p. PDF 2045587 invalidated

46033201 Marino, T.; McClymont, E.; Hales, C.; et. al. (2003) Revised Report for 3,5,6-

Trichloro-2-Pyridinol (TCP): Evaluation of the Toxicity to the Early Life Stages of 

the Rainbow Trout, Oncorhynchus mykiss Walbaum. Project Number: 011150, 

011150R. Unpublished study prepared by The Dow Chemical Co. 69 p. See 

44997301

45861301 Machado, M. (2003) Triclopyr Metabolite 3,5,6-TCP--Full Life-Cycle Toxicity Test 

with Water Fleas, Daphnia magna, under Static-Renewal Conditions: Lab Project 

Number: 12550.6286: 021300. Unpublished study prepared by Springborn Smithers 

Laboratories. 66 p. 

72-7 Simulated or Actual Field Testing 

MRID Citation Reference

Triclopyr BEE Study

151961 Washburn & Gillis Associates Ltd. (1983) Assessment of the Effects of the Herbicide 

Garlon 4 on Aquatic Fauna [Including Methods for Analysis of Soils and Water]. 

Unpublished study. 88 p. ACC 259512

122-1 850.4400 and 850.4150 

Seedling Emergence and Vegetative Vigor Tier 1 

MRID Citation Reference

Triclopyr Acid – No data

Triclopyr TEA Salt Studies

41784401 Weseloh, J.; Stockdale, G. (1990) A Study to Determine the Effects of Triclopyr on 

Vegetative Vigor: Lab Project Number: GH-P 1474. Unpublished study prepared by 
71

DowElanco/Midland Field Research Station. 47 p. TEA Salt at 9.0 Lbs ae per Acre PDF 

2022103

42908301 Weseloh, J. (1993) Supplemental Information for MRID 41734301: A Study to 

Determine the Effects of Triclopyr on Seed Germination and Seedling Emergence: Lab 

Project Number: MLJ083093. Unpublished study prepared by DowElanco. 11 p. 

41734301 Weseloh, J.; Stockdale, G. (1990) A Study to Determine the Effects of Triclopyr on Seed 

Germination and Seedling Emergence: Lab Project Number: GH-P 1475: 90032. 

Unpublished study prepared by DowElanco. 55 p. TEA Salt at 9.0 Lbs ae per Acre PDF 

2022101

Triclopyr BEE Studies

41734301 Weseloh, J.; Stockdale, G. (1990) A Study to Determine the Effects of Triclopyr on Seed 

Germination and Seedling Emergence: Lab Project Number: GH-P 1475: 90032. 

Unpublished study prepared by DowElanco. 55 p. . Triclopyr BEE at 8.0 Lbs ae per Acre 

PDF 2022101

41784401 Weseloh, J.; Stockdale, G. (1990) A Study to Determine the Effects of Triclopyr on 

Vegetative Vigor: Lab Project Number: GH-P 1474. Unpublished study prepared by 

DowElanco/Midland Field Research Station. 47 p. Applied Triclopyr BEE at 8.0 Lbs ae 

per Acre PDF 2022103

123-1 850.4400 and 850.4150 

Seed germination/seedling emergence and vegetative vigor 

MRID Citation Reference

Triclopyr TEA Salt Studies

43129801 Schwab, D. (1993) Evaluating the Effects of Triclopyr TEA on the Germination, 

Emergence, and Vegetative Vigor of Non-Target Terrestrial Plants: Final Report: Lab 

Project Number: 40874. Unpublished study prepared by ABC Lab., Inc. 168 p. PDF 

2045586

40346508 Smith, L.; Geronimo, J. (1977) Response of Seven Crops to Six Auxin-like 

Herbicides. Unpublished study prepared by Dow Chemi- cal. 29 p. PDF 2045591

Triclopyr BEE Study

43650001 Schwab, D. (1995) Evaluating the Effects of Triclopyr BEE on the Seedling 

Emergence and Vegetative Vigor of Non-Target Terrestrial Plants: Lab Project 

Numbers: 41964: RES94090. Unpublished study prepared by ABC Labs., Inc. 152 p. 

PDF 2022132

123-2 850.4400 and 850.5400 Aquatic plant growth 

MRID Citation Reference

Triclopyr Acid Study
72

41736303 Cowgill, U.; Milazzo, D. (1989) Triclopyr Acid: Evaluation of The Five Day Toxicity 

to The Green Alga Selenastrum Capricornutum: Lab Project Number: ES-DR-0040-

8195-8: ES-2047. Unpublished Study prepared by The Dow Chemical Co. 15 p. PDF 

2035116

Triclopyr TEA Salt Studies

41633705 Dill, D.; Milazzo, D. (1987) Triclopyr Triethylamine Salt: Evalua- tion of the 

Toxicity to a Freshwater Green Alga, Selenastrum Ca- pricornutum Printz: Lab 

Project Number: ES/DR/0287/8071/2. Un- published study prepared by The Dow 

Chemical Co. 16 p. PDF 2045573

41633706 Hughes, J. (1987) Triclopyr Triethylamine Salt: the Toxicity to An- abaena flosaquae: Lab Project Number: 0460/02/1100/1. Unpub- lished study prepared by 

Malcolm Pirnie, Inc. 25 p. PDF 2045574

41633707 Cowgill, U.; Milazzo, D. (1987) Triclopyr Triethylamine Salt: The Five Day Toxicity 

of Skeletonema Costatum Grev. Cleve Bacillari- ophyceae, Clone Skel, A Marine 

Diatom: Lab Project Number: ES/ dr/0287/8071/3. Unpublished study prepared by 

The Dow Chemical Company. 18 p. PDF 2045575

41633708 Hughes, J. (1987) Triclopyr Triethylamine Salt: The Toxicity to Navicula pelliculosa: 

Lab Project Number: 0460/02/1100/2. Un- published study prepared by Malcolm 

Pirnie, Inc. 24 p. PDF 2045576

41633709 Cowgill, U.; Milazzo, D. (1987) Triclopyr Triethylamine Salt: The Fourteen-Day 

Toxicity to Lemna Gibba L. G-3 Duckweed: Lab Pro- ject Number: 

ES/DR/0287/8071/1. Unpublished study prepared by The Dow Chemical Company. 

19 p. PDF 2045577

41736302 Cowgill, U.; Milazzo, D.; Landenberger, B. (1988) A Comparison of the Effect of 

Triclopyr Triethylamine Salt (Garlon 3A) on Two Species of Duckweed Examined 

For Seven-Day and Fourteen Day Period: Lab Project Number: ES-DR-0003-7070-2. 

Unpublished study prepared by Dow Chemical Co. 49 p. PDF 2045581

42090413 Mayes, M. (1991) Response to Phase 3 Submission on Triethylammonium 

Triclopyr...?Growth and Reproduction of Aquatic Plants Tier 2: Lemna gibba|: Lab 

Project Number: ES-970. Unpublished study prepared by Dow Chemical Co., 

Environmental Tox & Chem Res. Lab. 21 p. 

42090414 Mayes, M. (1991) Response to Phase 3 Submission on Triethylammonium 

Triclopyr...?Growth and Reproduction of Aquatic Plants Tier 2: Skeletonema 

costatum|: Lab Project Number: ES-971. Unpublished study prepared by Dow 

Chemical Co., Environmental Tox & Chem. Res. Lab. 11 p. 

48939403 Wemhoner, U. (2006) GF-1883 - Growth Inhibition Test with Freshwater Diatom 

(Navicula pelliculosa). Project Number: 060393/OCR, 1072/010/440. Unpublished 

study prepared by Springborn Smithers Laboratories (Europe). 71p.

Triclopyr BEE Studies

41633704 Cowgill, U.; Milazzo, D. (1989) GARLON 4 Herbicide: Evaluation of the Five Day 

Toxicity to the Green Alga Selenastrum Capricornu- tum: Lab Project Number: 

ES/DR/0224/6186/1. Unpublished study prepared by The Dow Chemical company. 

18 p. PDF 2022097 or 2045572

42090422 Mayes, M. (1991) Response to Phase 3 Submission on Butoxyethyl Triclopyr...?Growth and Reproduction of Aquatic Plants Tier 2: Selenaestrum 

capricornutum|. Unpublished study prepared by Dow Chemical Co., Environmental 

Tox & Chem Res. Lab. 16 p. 
73

42719101 Milazzo, D.; Servinski, M.; Weinberg, J.; et al. (1993) Triclopyr Butoxyethyl Ester: 

Toxicity to the Aquatic Plant, Duckweed, Lemna gibba L. G-3: Lab Project Number: 

ES-2592: DECO-ES-2592. Unpublished study prepared by The Dow Chemical Co. 

38 p. PDF 2022120

42721101 Hughes, J.; Alexander, M. (1993) The Toxicity of Triclopyr Butoxyethyl Ester 

(Triclopyr BEE) to Anabaena flos-aquae: Lab Project Number: ES-DR-0133-7242: 

ES-2529. Unpublished study prepared by Malcolm Pirnie, Inc. 37 p. PDF 2022118

42721102 Hughes, J.; Alexander, M. (1993) The Toxicity of Triclopyr Butoxyethyl Ester 

(Triclopyr BEE) to Navicula pelliculosa: Lab Project Number: ES-DR-0133-7242: 

ES-2530. Unpublished study prepared by Malcolm Pirnie, Inc. 37 p. PDF 2022118

42721103 Hughes, J.; Alexander, M. (1993) The Toxicity of Triclopyr Butoxyethyl Ester 

(Triclopyr BEE) to Skeletonema costatum: Lab Project Number: ES-DR-0133-7242: 

ES-2531. Unpublished study prepared by Malcolm Pirnie, Inc. 38 p. PDF 2022119

42645901 Hughes, J.; Williams, T. (1993) The Toxicity of Access Herbicide Formulation to 

Selenastrum capricornutum: Lab Project Number: ES-2587: B460-152-1. 

Unpublished study prepared by Malcolm Pirnie, Inc. 35 p. PDF 2039127

43230301 Ward, T.; Kowalski, P.; Boeri, R. (1994) Access Herbicide: Toxicity to the 

Freshwater Diatom, Navicula pelliculosa: Lab Project Number: 430/DO: ES/2766. 

Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 25 p. Triclopyr 

BEE/Picloram EHE PDF 2039127

43230304 Ward, T.; Kowalski, P.; Boeri, R. (1994) Access Herbicide: Toxicity to the Marine 

Diatom, Skeletonema costatum: Lab Project Number: 431/DO: ES/2767. 

Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 25 p. PDF 2001400

43230307 Boeri, R.; Kowalski, P.; Ward, T. (1994) Access Herbicide: Toxicity to the 

Freshwater Blue-Green Alga, Anabaena flos-aquae: Lab Project Number: 432/DO: 

ES/2768. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 25 p. PDF 

2039125

43230310 Milazzo, D.; Kirk, H.; Humbert, L.; et al. (1994) The Toxicity of Access Herbicide 

Formulation to the Aquatic Plant, Duckweed, Lemna gibba L.G-3: Lab Project 

Number: DECO/ES/2762. Unpublished study prepared by The Environmental 

Toxicology & Chemistry Research Lab. 33 p. PDF 2039124

TCP Degradate Studies

45312001 Kirk, H.; Gilles, M.; Hugo, J. et al. (1999) Effect of 3,5,6-Trichloro-2-Pyridinol 

(TCP) on the Growth of the Freshwater Green Alga, Selenastrum capricornutum, 

PRINTZ: Lab Project Number: 991194. Unpublished study prepared by The Dow 

Chemical Company. 43 p. PDF 2082443

45312002 Kirk, H.; Gilles, M.; McClymont, E. et al. (2000) 3,5,6-Trichloro-2-Pyridinol (TCP): 

Growth Inhibition Test with the Freshwater Aquatic Plant, Duckweed, Lemma gibba 

L. G-3: Lab Project Number: 001148. Unpublished study prepared by The Dow 

Chemical Company. 39 p. PDF 208244

45312003 Kirk, H.; Gilles, M.; McClymont, E. et al. (2000) 3,5,6-Trichloro-2-Pyridinol (TCP): 

Growth Inhibition Test with the Bluegreen Alga, Anabaena flos-aquae: Lab Project 

Number: 001149. Unpublished study prepared by The Dow Chemical Compamy. 38 

p. PDF 2082445
74

141-1 850.3020 Honey bee acute contact 

MRID Citation Reference

Triclopyr Acid Studies

40356602 Dingledine, J. (1985) Triclopyr Acid: An Acute Contact Toxicity Study with Honey Bees: 

Final Report: Laboratory Project ID 103-239. Unpublished study prepared by Wildlife 

International, Ltd. 14 p. PDF 2035115

Triclopyr TEA Salt 

No data

Triclopyr BEE Studies

41219109 Dingledine, J. (1985) Triclopyr BE Ester: An Acute Contact Toxicity Study with Honey 

Bees: Final Report: Project Study ID: 103-240. Unpublished study prepared by Wildlife 

International Ltd. 15 p. PDF 2022104

42625901 Hoxter, K.; Bernard, W.; Smith, G. (1992) Access Herbicide: An Acute Contact Toxicity 

Study with the Honey Bee: Lab Project Number: ES-2602: 103-389. Unpublished study 

prepared by Wildlife International Ltd. 20 p. PDF 2039123

NON Guideline Selections 

MRID Citation Reference

151964 Batchelder, T. (1975) Environmental Analysis and Special Fish Toxicities of Two Triclopyr 

Formulations. Unpublished study pre- pared by Dow Chemical Co. 20 p. ACC 259512

42305500

42305501

Texas Dept. of Agriculture (1992) Submission of a Report of the Investigation of a 

Complaint of Adverse Effects of Garlon 3A and Rodeo on Horses and Property in 

Accordance with FIFRA 6(a)2 Requirements. Transmittal of 1 study. Incident Report

151957 Batchelder, T.; Milazzo, D. (1981) Evaluation of Garlon 3A Herbi- cide in the Aquatic 

Environment: ES-362. Unpublished study pre- pared by Environmental Sciences Research 

Laboratory, Dow Chemi- cal U.S.A. 46 p. General summary

42411805 Woodburn, K. (1992) Fish Metabolism Study on Triclopyr Requested by EPA for Aquatic 

Registration: Lab Project Number: KBW-792. Unpublished study prepared by DowElanco. 

5 p. 

43474200 DowElanco (1994) Submission of DERBI Numbers for Adverse Effect Incidents in Support 

of FIFRA 6(a)(2) for Chlorpyrifos and Other Chemicals. Transmittal of 1 Study. 

44292003 Wolt, J.; Weglarz, T.; Wright, J.; et al. (1997) Triclopyr Non-Target Plant Risk Assessment: 

Lab Project Number: GH-C 4357. Unpublished study prepared by DowElanco. 95 p. 

44385901 Eisenbrandt, D.; Nolan, R.; McMaster, S. et al. (1997) Triclopyr: An Assessment of 

Common Mechanism of Toxicity: Lab Project Number: HET K-042085-097. Unpublished 

study prepared by The Dow Chemical Co. 15 p. 

44015101

44456102

44456103

44456104

44456108

44456112

45170901

Triclopyr in Fish and Shellfish: Evaluation of

Residue Data and Analytical Methods.

HED Studies listed on FOIA website
75

47164601 Moore, D.; Breton, R.; Rodney, S.; et al. (2007) Generic Problem Formulation for 

California Red-Legged Frog. Project Number: 89320, 05232007. Unpublished study 

prepared by Cantox Environmental Inc. 87 p. Registrant assessment

47164602 Holmes, C.; Vamshi, R. (2007) Data and Methodology Used for Spatial Analysis of 

California Red Legged Frog Observations and Proximate Land Cover Characteristics. 

Project Number: 3152007, WEI/252/03. Unpublished study prepared by Waterborne 

Environmental, Inc. (WEI). 19 p. ESA report from consulting firm

47164600 Croplife America (2007) Submission of Environmental Fate and Exposure and Risk Data in 

Support of the Preservation of the California Red Legged Frog. Transmittal of 2 Studies.

Registrant assessment

48216801 Patterson, B. (2010) Co-Occurrence of 2,4-D and Triclopyr in Water Monitoring Samples 

within Threatened and Endangered Salmonid: Evolutionarily Significant Units. Project 

Number: 102388/F. Unpublished study prepared by Stone Environmental, Inc. 70 p.

48216802 Patterson, B. (2010) Land Cover Characterization and Water Monitoring Data Summaries 

for Triclopyr Butoxyethyl Ester Within Threatened or Endangered Salmonid Evolutionarily 

Significant Units. Project Number: 102388/G. Unpublished study prepared by Stone 

Environmental, Inc. 112 p.

48304701 Gelis, C. (2008) (Green S): Measurement of Ground Contamination Underneath Brushwood 

Canopies: Final Report. Project Number: DOW/GRE/07001. Unpublished study prepared 

by ADME Bioanalyses. 170 p.
76

 Appendix B 

Comparison Table Eco effect data to ECOSAR predicted endpoints 

Acute Toxicity Actual in bold (when available) and ECOSAR Predicted in parenthesis 

Test Material FW Fish 96 Hr Daphnid 48 hr Aquatic Algae 96 hr

Triclopyr Acid 117 ppm( 18.34 ppm) 132.9 ppm(13.0 ppm) 32.5 ppm ( 38.4 ppm)

Triclopyr BEE 0.36 ppm (3.18 ppm) 0.35 ppm (5.33 ppm) 24hr=0.1 ppm (1.65 ppm)

TCP Degradate 12.5 ppm (5.9 ppm) 10.4 ppm (2.7 ppm) 2.0 ppm (11.6 ppm)

ECOSAR Predictions - No actual data available

TMP Degradate 1.02 ppm 0.81 ppm 9.7 ppm 

Photo Degradate

5,6-Dichloro-3-

hydroxy-3Hpyridin-2-one

1634 ppm 1164 ppm 1002 ppm

Photo Degradate 

(5/6)-Chloro-3-

hydroxy-spyridinone

1634 ppm 1164 ppm 1002 ppm

Oxamic acid 6.53x105 ppm 2.47 x 10 5ppm 34313 ppm

Triethylamine 40.6 ppm 4.58 ppm 4.23 ppm

Triethylammonium 70483 ppm 29630 ppm 6368 ppm

Butoxyethanol 1889 ppm 935 ppm 403 ppm

Chronic Toxicity Actual (when available) and ECOSAR Predicted in parenthesis 

Test Material Fish Chronic Daphnia Chronic

Triclopyr Acid No data (3.335 ppm) No data (0.408 ppm)

Triclopyr BEE 0.026 ppm (0.157 pm) No data (2.0 ppm)

TCP Degradate Invalid (0.69 ppm) 2.7 ppm (0.53 ppm)

TMP Degradate No data (0.098 ppm) No data (0.018 ppm)

Photo Degradate 5,6-

Dichloro-3-hydroxy-3Hpyridin-2-one

No data (2457 ppm) No data (0.69 ppm)

Photo Degradate (5/6)-

Chloro-3-hydroxy-spyridinone

No data (2427 ppm) No data (0.69 ppm)

Oxamic acid No data ( 39529 ppm) No data (7778 ppm)

Triethylamine No data (2.8 ppm) No data (0.36 ppm)

Triethylammonium No data (4832 ppm) No data (1251 ppm)

Butoxyethanol No data (157.3 ppm) No data (63 ppm)

Chemical : ECOSAR Class Selected for Each Test Material 

Triclopyr Acid: Halopyridines – acid 

Triclopyr BEE: Esters 

TCP degradate: Phenols 

TMP degradate: Halopyridines 
77

Photo-degradates 1 and 2 : 5,6-Dichloro-3-hydroxy-3H-pyridin-2-one and (5/6)-Chloro-3-

hydroxy-s-pyridinone: Vinyl/Allyl Halides 

Oxamic acid ,Triethylammonium and Butoxyethanol degradates : Neutral Organics 

Triethylamine: Aliphatic amines 
78

Appendix C

Pending and Active Registrations For 

116001 / 55335-06-3 / Triclopyr Acid

Registration 

#

Registration Name Compa

ny # Company Name Current 

Status % of Active Ingredient

Products containing Triclopyr Acid Only

1812-ULG STRADA 

HERBICIDE 1812 GRIFFIN L.L.C. Pending 44.4% Triclopyr acid

5905-580 TRYCERA 5905 HELENA 

CHEMICAL CO Active 29.4% Triclopyr acid

35935-55

NUFARM 

TRICLOPYR ACID 

TECHNICAL

35935 NUFARM LIMITED Active 98% Triclopyr acid

42750-123 TRICLOPYR TGAI 42750 ALBAUGH INC Active 98% Triclopyr acid

42750-191 TRICLOPYR TGAI II 42750 ALBAUGH INC Active 98% Triclopyr acid

42750-197 TRICLOPYR TGAI 

III 42750 ALBAUGH INC Active 98% Triclopyr acid

62719-533 TRICLOPYR ACID 

TECHNICAL 62719 DOW AGROSCIENCES Active 98.8% Triclopyr acid

83558-29 TRICLOPYR 

TECHNICAL (ACID) 83558

CELSIUS 

PROPERTY B.V., 

AMSTERDAM NL

Active 98% Triclopyr acid

62719-EUP8

62719 DOW 

AGROSCIENCES Active 44.4% Triclopyr acid

Products with Mixtures of 2 or More Active Ingredients

None 

Located

Total =8 Products * Does not include Special State Registrations
79

Pending and Active Registrations For 

116002 / 57213-69-1 / Triclopyr, triethylamine salt 

Registration 

#

Registration Name

Com

pany 

#

Company 

Name Status % of Active Ingredient

Products containing Triclopyr Triethylamine salt only

228-520 TRICLOPYR 3 

HERBICIDE 228

NUFARM 

AMERICAS, 

INC.

Active 44.4% Triclopyr TEA

228-597 NUP-07333 

HERBICIDE 228

NUFARM 

AMERICAS, 

INC.

Active 14% Triclopyr TEA

239-2491

ORTHO BRUSH-BGON BRUSH 

KILLER

239 THE SCOTTS 

COMPANY Active 8% Triclopyr TEA

239-2587

BRUSH-B-GON 

POISON IVY & 

POISON OAK 

KILLER

239 THE SCOTTS 

COMPANY Active 0.7% Triclopyr TEA

802-594

LILLY MILLER 

BLACKBERRY &

BRUSH KILLER

802 LILLY MILLER 

BRANDS Active 8% Triclopyr TEA

802-596

LILLY/MILLER 

READY-TO-USE 

BLACKBERRY & 

BRUSH KILLER

802 LILLY MILLER 

BRANDS Active 0.75% Triclopyr TEA

8959-56 NAVITROL 

LANDSCAPE 8959 APPLIED 

BIOCHEMISTS Active 44.4% Triclopyr TEA

42750-127 TRICLOPYR 44% 

TEA IVM 42750 ALBAUGH INC Active 44.4% Triclopyr TEA

42750-128 TRICLOPYR 44% 

TEA RICE 42750 ALBAUGH INC Active 44.4% Triclopyr TEA

42750-200

TRICLOPYR 44% 

TEA MUP 

HERBICIDE

42750 ALBAUGH INC Active 44.4% Triclopyr TEA

42750-243 TRICLOPYR 8.8% 42750 ALBAUGH INC Active 8.8% Triclopyr TEA

53883-216 TRICLOPYR 8.8% 

HERBICIDE 53883

CONTROL 

SOLUTIONS, 

INC.

Active 8.8% Triclopyr TEA

62719-37 GARLON 3A 62719

DOW 

AGROSCIENCE

S LLC

Active, 44.4% Triclopyr TEA
80

62719-53

TRICLOPYR, 

TRIETHYLAMINE 

SALT SOLUTION

62719

DOW 

AGROSCIENCE

S LLC

Active 44.4% Triclopyr TEA

62719-187 RENOVATE 

HERBICIDE 62719

DOW 

AGROSCIENCE

S LLC

Active 44.4% Triclopyr TEA

62719-215 GRANDSTAND R 62719

DOW 

AGROSCIENCE

S LLC

Active 44.4% Triclopyr TEA

62719-226 DOWELANCO 

BRUSH AND WEED 62719

DOW 

AGROSCIENCE

S LLC

Active 8.8% Triclopyr TEA

62719-257 TURFLON AMINE 62719

DOW 

AGROSCIENCE

S LLC

Active 44.4% Triclopyr TEA

62719-338 CROSSBOW SF 62719

DOW 

AGROSCIENCE

S LLC

Active 44.4% Triclopyr TEA

66222-152 TRICLOPYR 3 SL 66222

MAKHTESHI

M AGAN OF 

N. AMERICA, 

INC.

Active 44.4% Triclopyr TEA

67690-42 RENOVATE 

GRANULAR 67690 SEPRO 

CORPORATION Active 14% Triclopyr TEA

70506-228 TRIKE 70506

UNITED 

PHOSPHORUS, 

INC

Active 44.4% Triclopyr TEA

70506-265 KRAKEN 70506

UNITED 

PHOSPHORUS, 

INC

Active 44.4% Triclopyr TEA

72155-19

TRICLOPYR 8.8% 

CONCENTRATE 

HERBICIDE

72155 BAYER 

ADVANCED

Active

8.8% Triclopyr TEA

72155-22 TRICLOPYR 0.8% 

RTU 72155 BAYER 

ADVANCED

Active 0.8% Triclopyr TEA

81927-13 ALLIGARE 

TRICLOPYR 3 81927 ALLIGARE, LLC Active 44.4% Triclopyr TEA

83558-28 TRICLOPYR TEA 

MC 83558

CELSIUS 

PROPERTY 

B.V., 

AMSTERDAM 

(NL) 

Active

44.4% Triclopyr TEA

Multi Active Formulated Products with Triclopyr TEA

228-313

HORSEPOWER 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active 49% MCPA DMA

5.59 % Triclopyr TEA

4.8% Dicamba TEA
81

228-316

TURFLON II 

AMINE 228

NUFARM 

AMERICAS, 

INC.

Active 34.2 % 2,4-D

15.2% Triclopyr TEA

228-324

RIVERDALE 

SWEET SIXTEEN 

XL WEED AND 

FEED WITH 

HORSEPOWER

228

NUFARM 

AMERICAS, 

INC.

Active

1.6% MCPA DMA salt 

0.184 % Triclopyr TEA

0.16 % Dicamba DMA salt

228-325

RIVERDALE 

SWEET SIXTEEN 

WEED AND FEED 

WITH 

HORSEPOWER

228

NUFARM 

AMERICAS, 

INC.

Active

1.1% MCPA

0.12 % Triclopyr TEA

0.11% Dicamba

228-326 HORSEPOWER 

WEED AND FEED 228

NUFARM 

AMERICAS, 

INC.

Active 0.093 % Triclopyr TEA

0.8 % MCPA

0.08 % Dicamba

228-327

RIVERDALE 

HORSEPOWER L.A. 

WEED AND FEED

228

NUFARM 

AMERICAS, 

INC.

Active 0.08 % Triclopyr TEA

0.7 % MCPA 

0.07 % Dicamba

228-328

HORSEPOWER 

GRANULAR WEED 

KILLER

228

NUFARM 

AMERICAS, 

INC.

Active 1.1 % MCPA DMA

0.12 % Triclopyr TEA

0.11 Dicamba DMA

228-334

RIVERDALE 

HORSEPOWER 

LAWN WEED 

KILLER

228

NUFARM 

AMERICAS, 

INC.

Active 13.7% MCPA DMA

1.56 % Triclopyr TEA

1.3 % Dicamba DMA

228-335

RIVERDALE 

HORSEPOWER 8000 

LAWN WEED 

KILLER

228

NUFARM 

AMERICAS, 

INC.

Active 10.97% MCPA DMA 

1.25% Triclopyr TEA 

1.08% Dicamba DMA

228-336

HORSEPOWER 

SPOT WEED 

KILLER

228

NUFARM 

AMERICAS, 

INC.

Active

0.74 % MCPA DMA 

0.084% Triclopyr TEA 

0.07% Dicamba DMA

228-355

RIVERDALE 

ENTERPRISE 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active

56.9% 2,4-D TIPA 

5.37% Triclopyr TEA 

3.8% Dicamba TEA

228-356

DTDA/DMA-TEADMA SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active

37.3% 2,4-D TIPA 

5.42% Triclopyr TEA 

4.7% Dicamba 

228-GAG

RIVERDALE TSC 

PREMIUMLAWN 

WEED KILLER

228

NUFARM 

AMERICAS, 

INC.

Pending 

11.36 % 2,4-D TIPA 

0.84% Triclopyr TEA 

0.3 %Clopyralid 
82

228-371

RIVERDALE MTCA 

PREMIUM 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active

37.9% MCPA DMA

3.8 %Triclopyr TEA 

1.3 %Clopyralid

228-GOE

RIVERDALE 

TURFLON II IVM 

AMINE

228

NUFARM 

AMERICAS, 

INC.

Pending 

34.2 % 2,4-D DMA 

15.2% Triclopyr TEA 

228-402

RIVERDALE 

SWEET SIXTEEN 

WEED AND FEED 

WITH DTDA

228

NUFARM 

AMERICAS, 

INC.

Active

2.0% 2,4-D TIPA salt 

0.251% Triclopyr TEA 

0.09% Dicamba 

228-403

RIVERDALE DTDA 

GRANULAR WEED 

KILLER

228

NUFARM 

AMERICAS, 

INC.

Active 2.0% 2,4-D TIPA salt 

0.251% Triclopyr TEA 

0.09% Dicamba 

228-404

RIVERDATE DTDA 

12800 LAWN WEED 

KILLER

228

NUFARM 

AMERICAS, 

INC.

Active 20.16% 2,4-D TIPA salt 

1.93% Triclopyr TEA 

1.38% Dicamba 

228-405 DTDA 10000 LAWN 

WEED KILLER 228

NUFARM 

AMERICAS, 

INC.

Active 16.2 % 2,4-D TIPA salt 

1.51% Triclopyr TEA 

1.08 %Dicamba 

228-406

RIVERDALE DTDA 

8000 LAWN WEED 

KILLER 

228

NUFARM 

AMERICAS, 

INC.

Active 12.9% 2,4-D TIPA salt 

1.2% Triclopyr TEA 

0.09% Dicamba 

228-407 DTDA SPOT WEED 

KILLER 228

NUFARM 

AMERICAS, 

INC.

Active 1.23% 2,4-D TIPA salt 

0.11 % Triclopyr TEA 

0.08% Dicamba 

228-411

RIVERDALE WILPOWER 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active 46.9% MCPA DMA 

10.68% Triclopyr TEA 

9.12 % 2,4-DP-p DMA 

228-418 RIVERDALE 

MOMENTUM FX 228

NUFARM 

AMERICAS, 

INC.

Active 44.2% 2,4-D TIPA salt

3.31% Triclopyr TEA 

8.52% Fluroxypyr 1 methyl 

heptyl ester 

228-422

RIVERDALE 

BATTLESHIP 2 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active 37.48% MCPA DMA 

3.45% Triclopyr TEA 

8.9% Fluroxypyr 1 methyl 

heptyl ester

228-424 HORSEPOWER 

CONCENTRATE 228

NUFARM 

AMERICAS, 

INC.

Active 13.7% MCPA DMA 

1.56% Triclopyr TEA 

1.35% Dicamba DMA 
83

228-447 MOMENTUM FX2 

HERBICIDE 228

NUFARM 

AMERICAS, 

INC.

Active 44.2 % 2,4 D TIPA 

3.86%Triclopyr TEA 

4.2 % Fluroxypyr 1-

methylheptyl ester 

228-453

BATTLESHIP 3 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active 37.8% MCPA DMA 

4.07% Triclopyr TEA 

4.45% Fluroxypyr 1-

methylheptyl ester

228-564 BRAZEN 

HERBICIDE 228

NUFARM 

AMERICAS, 

INC.

Active 33 % Triclopyr TEA 

12.1% Clopyralid MEA salt

228-568 BRAZEN SF 

HERBICIDE 228

NUFARM 

AMERICAS, 

INC.

Active 33% Triclopyr TEA 

12.1% Clopyralid

228-590

4-SPEED XT 

SELECTIVE 

HERBICIDE

228

NUFARM 

AMERICAS, 

INC.

Active 41.2% 2,4-D EHE

4.81% Triclopyr TEA 

3.46% Dicamba

0.067% Pyaflufen ethyl

352-ITU DUPONT INVORA 

HERBICIDE 352

E. I. DU PONT 

DE NEMOURS 

AND 

COMPANY 

(S300/419)

Pending 20.4% Triclopyr TEA 

10.8% Aminocyclopyr TEA

961-390

LEBANON LAWN 

FERTILIZER 

CONTAINS 

CONFRONT AND 

TEAM

961

LEBANON 

SEABOARD 

CORPORATIO

N

Active 0.5%Triclopyr TEA 

0.43% Trifluralin/

0.82% Benfluralin/

0.18% Clopyralid TEA

961-391

LEBANON TURF 

FERTILIZER WITH 

CONFRONT AND 

TEAM 

961

LEBANON 

SEABOARD 

CORPORATIO

N

Active 0.5% Triclopyr TEA 

0.43% Trifluralin/

0.82% Benfluralin/

0.18% Clopyralid TEA

961-395 CONFRONT III + 

FERTILIZER 961

LEBANON 

SEABOARD 

CORPORATIO

N

Active 1.0 % 2,4-D DMA 

0.303% Triclopyr TEA 

0.20% Fluoroxypyr MHE/

961-406 CONFRONT* IV + 

FERTILIZER 961

LEBANON 

SEABOARD 

CORPORATIO

N

Active

0.303% Triclopyr TEA 

0.17 % Fluoroxypyr MHE/

0.82 % 2,4-D DMA

0.14 % Dithiopyr

2217-921 EH-1467 

HERBICIDE 2217 PBI/GORDON 

CORP

Active 30.8 % 2,4-D DEA 

7.28% Triclopyr TEA 

2.48 % Dicamba DMA
84

0.6% Sulfentrazone

2217-949 EH-1491 

HERBICIDE 2217 PBI/GORDON 

CORP

Active 30.8 % 2,4-D DEA

7.28% Triclopyr TEA 

2.48% Dicamba DMA

2217-950 EH-1492 

HERBICIDE 2217 PBI/GORDON 

CORP

Active 16.5 % 2,4-DP DEA salt

7.81% Triclopyr TEA 

1.4 % Dicamba DMA

34704-930 CHASER 2 AMINE 34704

LOVELAND 

PRODUCTS, 

INC.

Active 34.2 % 2,4-D DMA salt 

15.2% Triclopyr TEA 

34704-958 TAILSPIN 34704

LOVELAND 

PRODUCTS, 

INC.

Active 16.1% Triclopyr TEA 

5.6 %Fluroxypyr 1-MHE

42750-125

TRICLOPYR TEA + 

CLOPYRALID TEA 

R&P

42750 ALBAUGH 

INC

Active 33% Triclopyr TEA 

12.1% Clopyralid 

Triethanolamine

53883-332 QUALI-PRO 2TQ 53883

CONTROL 

SOLUTIONS, 

INC.

Active 38 % 2,4-D DMA

10.7% Triclopyr TEA 

3.3% Quinclorac

58501-2

WEEDEX 

DANDELION STICK 58501 TERAGRO 

INC.

Active 4.5 % 2,4-D DMA

2% Triclopyr TEA 

62719-92 CONFRONT 62719

DOW 

AGROSCIENC

ES LLC

Active 33% Triclopyr TEA 

12.1%Clopyralid 

triethanolamine

62719-217 XRM-5202 62719

DOW 

AGROSCIENC

ES LLC

Active 50.7 % 2,4-D TIPA

3.8% Triclopyr TEA 

1.3 % Clopyralid

62719-232 CONFRONT* F 62719

DOW 

AGROSCIENC

ES LLC

Active 33% Triclopyr TEA 

12.1% Clopyralid

62719-262

TURF FERTILIZER 

CONTAINS 

CONFRONT 62719

DOW 

AGROSCIENC

ES LLC

Active 0.5% Triclopyr TEA 

0.18% Clopyralid

62719-337 REDEEM R & P 62719

DOW 

AGROSCIENC

ES LLC

Active 33% Triclopyr TEA 

12.1% Clopyralid

62719-511 GARLON EV 62719

DOW 

AGROSCIENC

ES LLC

Active

16.1% Triclopyr TEA 

5.6% Fluroxypyr 1 

methylheptyl ester

62719-528 GF-1249 62719

DOW 

AGROSCIENC

ES LLC

Active 22.2 %Triclopyr TEA 

4.0% Picloram potassium
85

62719-572

MILESTONE VM 

PLUS 62719

DOW 

AGROSCIENC

ES LLC

Active 16.2% Triclopyr TEA 

2.22% Aminopyralid TIPA

62719-599 GF-2121 62719

DOW 

AGROSCIENC

ES LLC

Active

44.2 % 2,4-D TIPA 

3.86% Triclopyr TEA 

4.2% Fluroxypyr 1 

methylheptyl ester

62719-610 Grasp Xtra 62719

DOW 

AGROSCIENC

ES LLC

Active 23.0% Triclopyr TEA 

2.77% Penoxsulam

67690-50 SP1037 67690

SEPRO 

CORPORATIO

N

Active 14 % 2,4-D DMA 

4.0%Triclopyr TEA 

71085-29 RICEPYR 71085 RICECO LLC Active

36.5 % Propanil 

3.8% Triclopyr TEA 

71995-36

MON 78783 

HERBICIDE 71995 MONSANTO 

COMPANY Active

1.0 % Glyphosate IPA 

0.1 %Triclopyr TEA 

71995-37 MON 78736 

HERBICIDE 71995 MONSANTO 

COMPANY Active

18 %Glyphosate IPA 

2.0% Triclopyr TEA 

71995-41

RD 1645 

HERBICIDE 71995 MONSANTO 

COMPANY Active

1.2 % 2,4-D TIPA 

0.112% Triclopyr TEA 

0.08% Dicamba

71995-42

RD 1644 

HERBICIDE 71995 MONSANTO 

COMPANY Active

16.19 % 2,4-D TIPA 

1.51% Triclopyr TEA 

1.08% Dicamba

71995-48

RD 1662 

HERBICIDE 71995 MONSANTO 

COMPANY Active

2.0% Nonanoic acid/

1.0% Glyphosate 

Isopropylammonium

0.1% Triclopyr TEA 

71995-50

RD 1689 

HERBICIDE 71995 MONSANTO 

COMPANY Active

18% Glyphosate 

Isopropylammonium 

2.0% Triclopyr TEA 

1.0% Diquat

81927-30

ALLIGARE 

PRESCOTT 

HERBICIDE 81927 ALLIGARE, 

LLC Active 33% Triclopyr TEA 

12.1% Clopyralid TEA

Total =92 Products * Does not include Special State Registrations
86

Pending and Active Product Registrations For 

116004 / 64700-56-7 / Triclopyr, butoxyethyl ester

Registration 

#

Registration Name Comp

any #

Company Name Status % of Active Ingredient

Products Containing Only Triclopyr BEE

228-517 TAHOE 4E 228 NUFARM 

AMERICAS, INC. Active 61.6% Triclopyr BEE

228-521

RELEGATE 

SELECTIVE 

HERBICIDE

228 NUFARM 

AMERICAS, INC. Active 61.6% Triclopyr BEE

228-552 RELEGATE RTU 

HERBICIDE 228 NUFARM 

AMERICAS, INC. Active 13.6% Triclopyr BEE

17545-8 TURFLON ESTER 17545

BRANDT 

CONSOLIDATED, 

INC.

Active

60.45% Triclopyr BEE

35935-56

NURFARM 

TRICLOPYR BEE 

TECHNICAL

35935 NUFARM LIMITED

Active

98% Triclopyr BEE

42750-126 TRICLOPYR 4E 42750 ALBAUGH INC Active 61.6% Triclopyr BEE

42750-129 TRICLOPYR 61% BEE 

R&P 42750 ALBAUGH INC Active 61.6% Triclopyr BEE

42750-173 TRICLOPYR 13.6% BEE 42750 ALBAUGH INC Active 13.6% Triclopyr BEE

42750-174 TRICLOPYR BEE 

TECHNICAL 42750 ALBAUGH INC Active 98% Triclopyr BEE

42750-198 TRICLOPYR 61% BEE 

TURF 42750 ALBAUGH INC Active 61.6% Triclopyr BEE

51036-GIU Triclopyr 96% Ester 

Technical 51036 BASF SPARKS LLC Pending 96% Triclopyr BEE

51036-UEG TRICLOPYR 98% 

ESTER TECHNICAL 51036 BASF SPARKS LLC Pending 97.5% Triclopyr BEE

62719-40 GARLON 4 62719

DOW 

AGROSCIENCES 

LLC

Active 61.6% Triclopyr BEE

62719-70 REMEDY 62719

DOW 

AGROSCIENCES 

LLC

Active

61.6% Triclopyr BEE

62719-87

TRICLOPYR 

BUTOXYETHYL 

ESTER

62719

DOW 

AGROSCIENCES 

LLC

Active

96.3% Triclopyr BEE
87

62719-176 PATHFINDER II 62719

DOW 

AGROSCIENCES 

LLC

Active

13.6% Triclopyr BEE

62719-251 TURFLON ESTER F 62719

DOW 

AGROSCIENCES 

LLC

Active 61.6% Triclopyr BEE

62719-258 TURFLON ESTER 62719

DOW 

AGROSCIENCES 

LLC

Active

61.6% Triclopyr BEE

62719-527 GF-1529 62719

DOW 

AGROSCIENCES 

LLC

Active

60.45% Triclopyr BEE

62719-552 REMEDY ULTRA 62719

DOW 

AGROSCIENCES 

LLC

Active

60.45% Triclopyr BEE

62719-553 GARLON XRT 62719

DOW 

AGROSCIENCES 

LLC

Active

83.9% Triclopyr BEE

62719-566 TURFLON ESTER 

ULTRA 62719

DOW 

AGROSCIENCES 

LLC

Active

60.45% Triclopyr BEE

66222-153 TRICLOPYR 4 66222

MAKHTESHIM 

AGAN OF NORTH 

AMERICA, INC.

Active

61.6% Triclopyr BEE

69361-35 TRICLO 4 SPECIALTY 

HERBICIDE 69361 REPAR CORP Active 61.6% Triclopyr BEE

69361-34

TRICLOPYR 

BUTOXYETHYL 

ESTER TECHNICAL

69361 REPAR CORP

Active

98% Triclopyr BEE

70506-EL

TRICLOPYR 

BUTOXYETHYL 

ESTER TECHNICAL

70506 UNITED 

PHOSPHORUS, INC Pending 98.5% Triclopyr BEE

74779-8

RTSA IVM SPECIALTY 

HERBICIDE 74779

RAINBOW 

TREECARE 

SCIENTIFIC 

ADVANCEMENTS

Active

61.6% Triclopyr BEE

81927-11 ALLIGARE 

TRICLOPYR 4 81927 ALLIGARE, LLC 

Active 61.6% Triclopyr BEE

81927-33

ALLIGARE 

TRICLOPYR RTU 

HERBICIDE

81927 ALLIGARE, LLC 

Active

13.6% Triclopyr BEE

81927-48 ALLIGARE 

TRICLOPYR 4E 81927 ALLIGARE, LLC 

Active 61.6% Triclopyr BEE

83558-30 TRICLOPYR 

TECHNICAL (BEE) 83558

CELSIUS 

PROPERTY B.V., 

AMSTERDAM (NL) 

Active

98% Triclopyr BEE
88

Multi Active Formulated Products with Triclopyr BEE

228-317

COOL POWER 

SELECTIVE 

HERBICIDE

228 NUFARM 

AMERICAS, INC. Active

56% MCPA 2-EHE

5% Triclopyr BEE

3.6 % Dicamba

228-395 PROGENY HERBICIDE 228 NUFARM 

AMERICAS, INC. Active

56% MCPA 2-EHE

5% Triclopyr BEE

3.6 % Dicamba 

228-565 CANDOR HERBICIDE 228 NUFARM 

AMERICAS, INC. Active

34.4 % 2,4-D BEE 16.5 

% Triclopyr BEE

228-716 NUP-11032 HERBICIDE 228 NUFARM 

AMERICAS, INC. Active

5.0% Dicamba 

0.76% Triclopyr BEE

0.55% Fenoxyprop p 

ethyl

961-394

LEBANON FERTILIZER 

PLUS CONFRONT TR 

BRAND HERBICIDE

961

LEBANON 

SEABOARD 

CORPORATION

Active 0.4 % Triclopyr BEE

0.829 % 2,4-D BEE

2217-920 EH-1466 HERBICIDE 2217 PBI/GORDON CORP Active

31.8% 2,4-D 2-EHE

8.4 % Triclopyr BEE

0.73% Sulfentrazone

2.43% Dicamba

2217-951 EH-1493 HERBICIDE 2217 PBI/GORDON CORP Active

31.8% 2,4-D, 2-EHE

8.4 % Triclopyr BEE

2.43% Dicamba

2217-952 EH-1494 HERBICIDE 2217 PBI/GORDON CORP Active

16% 2,4-D 2-EHE

8.4 % Triclopyr BEE

1.2% Dicamba

2217-965 EH-1515 HERBICIDE 2217 PBI/GORDON CORP Active

55.5 % MCPA, 2-EHE

4.95% Triclopyr BEE

3.64% Dicamba

2217-966 EH-1514 HERBICIDE 2217 PBI/GORDON CORP Active

54.7 % MCPA, 2-EHE

9.3% Triclopyr BEE

3.6% Dicamba

2217-974 EH 1520 HERBICIDE 2217 PBI/GORDON CORP Active

30% 2,4-D 2-EHE

7.73% Triclopyr BEE

0.66% Sulfentrazone

2.8% Dicamba DMA

0.77% Penoxsulam

2217-975 EH 1528 HERBICIDE 2217 PBI/GORDON CORP Active 30% 2,4-D 2-EHE

3.89 Triclopyr BEE
89

0.67% Sulfentrazone

2.25% Dicamba

2217-976 EH 1527 HERBICIDE 2217 PBI/GORDON CORP

Active 29.3% 2,4-D 2-EHE

7.72% Triclopyr BEE

0.66% Sulfentrazone

2.22% Dicamba

34704-928 CHASER TURF 

HERBICIDE 34704 LOVELAND

PRODUCTS, INC.

Active 34.4 % 2,4-D BEE 16.5% 

Triclopyr BEE

42750-124 TRICLOPYR BEE + 2,4-

D BEE 42750 ALBAUGH INC

Active 34.4 % 2,4-D BEE 16.5% 

Triclopyr BEE

62719-67 TURFLON D 62719

DOW 

AGROSCIENCES 

LLC

Active 34.4 % 2,4-D BEE 16.5% 

Triclopyr BEE

62719-260 CROSSBOW 62719

DOW 

AGROSCIENCES 

LLC

Active 34.4 % 2,4-D BEE 16.5% 

Triclopyr BEE

62719-477 PASTUREGARD 62719

DOW 

AGROSCIENCES 

LLC

Active 25% Triclopyr BEE

8.6% Fluroxypyr 1-MHE

62719-637 PASTUREGARD HL 62719

DOW 

AGROSCIENCES 

LLC

Active 45.07% Triclopyr BEE

15.56% Fluroxypyr 1-

MHE

66222-222

QUALI-PRO 2-D 

HERBICIDE

Mixture

66222

MAKHTESHIM 

AGAN OF NORTH 

AMERICA, INC.

Active 33% Triclopyr BEE 

12 % Clopyralid TEA

81927-29 ALLIGARE EVERETT 

HERBICIDE 81927 ALLIGARE, LLC Active 34.4 % 2,4-D BEE 16.5% Triclopyr BEE

Total Products = 49 excluding Special State Exemption Registrations Three products are pending.
90

Appendix D 

Approved Site/Pest Information For 

Triclopyr acid, Triclopyr triethylamine salt and Triclopyr Butoxyethyl ester 

Site Information 

Site 

Code Site Name Actives

660000101 AGRICULTURAL (NONCROP AREAS) (FOLIAR TREATMENT) TEA

660002503 AGRICULTURAL (NONCROP AREAS) (STUMP TREATMENT) BEE only

610005901 AGRICULTURAL BUILDINGS (OUTDOOR) TEA and BEE

670010102 AIRPORTS (FOLIAR TREATMENT) TEA and BEE

670010204 AIRPORTS (SOIL TREATMENT) BEE only

350160106 ALDER (FOLIAR TREATMENT) TEA

230010106 ALFALFA (FOLIAR TREATMENT) TEA

030010206 ALMONDS (SOIL TREATMENT) TEA

330130106 ANNUAL BLUEGRASS (FOLIAR TREATMENT) Acid, TEA

330130101 ANNUAL BLUEGRASS (ORNAMENTAL TURF) (FOLIAR TREATMENT) TEA

330140103 ANNUAL RYEGRASS (FOLIAR TREATMENT) TEA

630010024 APARTMENTS (INDOOR) BEE only

040012401 APPLES (BASAL BARK TREATMENT) BEE Only

650000001 AQUATIC AREAS Acid, TEA

650006201 AQUATIC AREAS (SHORELINES) (SURROUNDING VEGETATION) (FOLIAR 

TREATMENT)

Acid, TEA

650006201 AQUATIC AREAS (SHORELINES) (SURROUNDING VEGETATION) (FOLIAR 

TREATMENT)

Acid, TEA

650006104 AQUATIC AREAS (WATER TREATMENT) TEA

650002302 AQUATIC VEGETATION (INJECTION TREATMENT) TEA

350220106 ASH (FOLIAR TREATMENT) TEA

350230107 ASPEN (BARK TREATMENT) BEE only

160020106 ASPARAGUS (FOLIAR TREATMENT) TEA

770000005 ATHLETIC FACILITIES TEA

670020107 ATHLETIC FIELDS (FOLIAR TREATMENT) TEA

330150-

BAHIAGRASS (athletic fields, cemeteries, dormant, golf courses, sod farms, rights of 

way, lawns, ornamental turf, parks, soil treatment

BEE and TEA

330150106 BAHIAGRASS (FOLIAR TREATMENT) Acid, TEA

240010106 BARLEY (FOLIAR TREATMENT) TEA

660020107 BARRIER STRIPS (FOLIAR TREATMENT) TEA

650316103 BAYOUS (SLOW FLOWING) (WATER TREATMENT) TEA
91

150010108 BEANS (DRY) (FOLIAR TREATMENT) TEA

030130201 BEECH NUT (SOIL TREATMENT) TEA

330160000

series

BENTGRASS, (soil, foliar, athletic fields, bowling greens, cemeteries, golf courses, 

sod farms, lawns, ornamental turf, parks)

BEE and TEA

330160106 BENTGRASS (FOLIAR TREATMENT) Acid and TEA

330170001 BERMUDAGRASS (soil, foliar, athletic fields, bowling greens, cemeteries, golf 

courses, sod farms, lawns, ornamental turf, parks)

TEA

330170106 BERMUDAGRASS (FOLIAR TREATMENT) Acid and TEA

350280106 BIRCH (foliar(TEA) or bark treatment (BEE)) BEE and TEA 

010020111 BLACKBERRIES (Bark treatment) BEE ONLY

351500103 BLACKJACK OAK (FOLIAR TREATMENT) BEE only

030120201 BLACK WALNUT (SOIL TREATMENT) TEA

330190001

series

BLUEGRASS (soil, foliar, athletic fields, bowling greens, cemeteries, golf courses, 

sod farms, lawns, ornamental turf, parks)

BEE and TEA

650336111 BOG LAKES (WATER TREATMENT) TEA

030020201 BRAZIL NUT (SOIL TREATMENT) TEA

330200106 BUFFALOGRASS (FOLIAR TREATMENT) Acid, BEE and TEA

330200110

series

BUFFALOGRASS (soil, foliar, athletic fields, bowling greens, cemeteries, golf 

courses, sod farms, lawns, ornamental turf, parks)

TEA

670030102 BUILDING FOUNDATIONS ( foliar treatment , soil treatment, non-agricultural) ( TEA

030100201 BUTTERNUTS (SOIL TREATMENT) TEA

630010006 CABINS (OUTDOOR) TEA

670020105 CAMP AREAS (FOLIAR TREATMENT) TEA

670020205 CAMP AREAS (SOIL TREATMENT) TEA

670020005 CAMP SITES TEA

650136110 CANALS Acid and TEA

650136109 CANALS (slow flowing, standing) TEA

030030201 CASHEWS (SOIL TREATMENT) TEA

330230106 CENTIPEDEGRASS (soil, foliar, athletic fields, bowling greens, cemeteries, golf 

courses, sod farms, lawns, ornamental turf, parks)

Acid, BEE and TEA

030040201 CHESTNUTS (SOIL TREATMENT) TEA

300050-

series

CHRISTMAS TREE PLANTINGS ( foliar treatment, soil treatment, stump 

treatments)

Acid and TEA

300050-

series

CHRISTMAS TREE PLANTINGS ( foliar treatment, soil treatment, stump 

treatments, frill treatment, injection)

TEA

020002501 CITRUS TREES (STUMP TREATMENT) BEE only

130040106 COLE CROPS (FOLIAR TREATMENT) TEA

770005914 COMMERCIAL/INSTITUTIONAL/INDUSTRIAL AREAS (OUTDOOR) TEA
92

300040001 CONIFER RELEASE (foliar, frill, injection, soil treatment, stump treatment) TEA

300040106 CONIFER RELEASE (foliar treatment only) Acid, BEE and TEA

300020202 CONIFER PLANTINGS (SOIL TREATMENT) BEE and TEA

660020109 CONSERVATION RESERVE PROGRAM LAND (soil and foliar treatment) Acid, TEA and BEE

280060106 CORN (FIELD) (foliar, seed, soil treatment) TEA

150040106 CORN (POP) (FOLIAR TREATMENT) TEA

150050106 CORN (SWEET) (FOLIAR TREATMENT) TEA

650130001 DITCH BANKS (foliar treatment) Acid, TEA and BEE

650130102 DITCH BANKS (foliar, frill, injection and stump treatments) TEA and BEE

650226201 DITCHES Acid, TEA, and BEE

350430107 DOGWOOD (BARK TREATMENT) BEE only

630030003 DOMESTIC DWELLINGS (OUTDOOR) TEA and BEE

350440106 DOUGLAS-FIR (foliar, dormant, forest, soil treatment) TEA

650130101 DRAINAGE DITCH BANKS (foliar, shoreline, slow-flowing, water treatment) TEA

670110002 DRIVEWAYS (foliar and soil treatment) TEA

350490107 ELM (bark treatment, cuttings, injection ) TEA

030090206 ENGLISH WALNUTS (soil treatment) TEA

660020105 FALLOW LAND (foliar and soil treatment) TEA

610005902 FARM BUILDINGS (OUTDOOR) Acid , TEA and BEE

660000105 FARM FUEL STORAGE AREAS (FOLIAR TREATMENT) TEA

660000102 FARM YARDS (FOLIAR TREATMENT) Acid, TEA and BEE

660000202 FARM YARDS (Soil, stump, dormant, basal bark treatment) BEE only

660010101 FENCE ROWS (FOLIAR TREATMENT) TEA

680090001 FENCEROWS (Foliar, Frill, nonagricultural, injection, soil treatment, stump 

treatment)

TEA

680090101 FENCEROWS (foliar treatment only) Acid, TEA and BEE

680090002 FENCES TEA

330310000 FESCUE (athletic fields, cemeteries, golf courses, sod farms, rights of way, lawns, 

ornamental turf, parks, soil treatment)

BEE and TEA

330310106 FESCUE (foliar treatment, chewings) Acid and TEA

330450106 FESCUE (CREEPING RED) ( golf courses, sod farms, lawns, ornamental turf, parks, 

soil treatment, foliar treatment)

TEA

330451602 FESCUE (CREEPING RED) (foliar treatment) Acid and TEA

030050206 FILBERTS (SOIL TREATMENT) TEA

331130111 FINE FESCUE (FOLIAR TREATMENT) Acid, BEE, TEA

350510106 FIR (foliar or soil treatment in forest ) BEE and TEA (forest)

280090106 FLAX (FOLIAR TREATMENT) TEA
93

650380101 FLOOD PLAIN (DRY) (FOLIAR TREATMENT) TEA ad BEE

650386116 FLOOD PLAINS (WATER TREATMENT) TEA

300000106 FOREST LANDS (foliar treatment) Acid, BEE and TEA

300002401 FOREST LANDS (BASAL BARK TREATMENT) Acid and TEA

300000103 FOREST LANDS (dormant, frill, injection, stump treatments) TEA

300040107 FOREST MANAGEMENT AREAS (foliar, frill, injection, stump treatments) Acid, BEE (Basal bark)

and TEA

300000107 FOREST TREES ( frill, injection, stump treatments, hardwoods) BEE and TEA

220000107 GRASSES (FORAGE) (FOLIAR TREATMENT) TEA

220000106 GRASSES (HAY) (FOLIAR TREATMENT) TEA

220000108 GRASSES (SILAGE) (FOLIAR TREATMENT) TEA

352400101 GRAY BIRCH (FOLIAR TREATMENT) TEA

670040109 GUARDRAILS (FOLIAR TREATMENT) TEA

350670105 HACKBERRY (BARK TREATMENT) BEE only

HARDWOODS (basal bark and stump treatment) BEE only

680090102 HEDGEROWS (FOLIAR TREATMENT) TEA

350690106 HICKORY (FOLIAR TREATMENT) TEA

030060201 HICKORY NUTS (SOIL TREATMENT) TEA

630030030 HOMES (OUTDOOR) TEA

630030031 HOMES (YARDS) (OUTDOOR) TEA

650316101 IMPOUNDED WATER TEA

670090103 INDUSTRIAL AREAS (OUTDOOR) (FOLIAR TREATMENT) TEA

670090101 INDUSTRIAL SITES (foliar (TEA and BEE) frill, stump, tree injection treatments) Acid, TEA and BEE 

650216202 IRRIGATION DITCH BANKS TEA

650216101 IRRIGATION CANALS Acid and TEA

650216102 IRRIGATION DITCHES TEA

650216109 IRRIGATION SUPPLY SYSTEMS (WATER TREATMENT) Acid, TEA, and BEE

330340106 KENTUCKY BLUEGRASS (FOLIAR TREATMENT) Acid, BEE, and TEA

KENTUCKY BLUEGRASS (sod farms) BEE

330340126 KENTUCKY BLUEGRASS FESCUE (athletic fields, cemeteries, golf courses, sod 

farms, rights of way, lawns, ornamental turf, parks, soil, and seed treatment)

TEA

330350201 KIKUYUGRASS (ORNAMENTAL TURF) (SOIL TREATMENT) TEA

650316201 LAKES (shoreline) Acid and TEA

650316104 LAKES (slow flowing, and standing as water treatment)) TEA

150110106 LENTILS (FOLIAR TREATMENT) TEA

650146102 LIVESTOCK DRINKING WATER Acid and TEA
94

350770106 LOCUST (FOLIAR TREATMENT and Dormant) BEE only

670090104 LUMBER YARDS (foliar or soil treatment (BEE only)) TEA and BEE

030070206 MACADAMIA NUTS (SOIL TREATMENT) TEA

650330101 MARSH/SWAMP (surrounding vegetation foliar treatment) Acid, TEA, and BEE

650336204 MARSHES (surface, surrounding vegetation, water treatment) TEA

342520000 MESQUITE (bark treatment) BEE only

670000105 MILITARY INSTALLATIONS (OUTDOOR) (FOLIAR TREATMENT) TEA and BEE

280120106 MINT (FOLIAR TREATMENT) TEA

680050000 NON-AGRICULTURAL AREAS (PUBLIC HEALTH) TEA

680050002 NONAGRICULTURAL AREAS (WILDLIFE REFUGE) TEA

670000004 NONCROP AREAS (dormant, foliar, injection stump treatments) Acid , BEE and TEA

670000101 NONCROP AREAS (Frill, soil, wild host plant treatments) TEA and BEE

670000102 NONGRAZING AREAS (FOLIAR TREATMENT) Acid and TEA

240030106 OATS (FOLIAR TREATMENT) TEA

140110107 ONIONS (FOLIAR TREATMENT) TEA

280362501 ORCHARDS (STUMP TREATMENT) TEA

350000000 ORNAMENTAL AND/OR SHADE TREES (ALL OR UNSPECIFIED) TEA

310030208 ORNAMENTAL FLOWERING PLANTS (BEDDING) (SOIL TREATMENT) TEA

310000101 ORNAMENTAL HERBACEOUS PLANTS (FOLIAR TREATMENT) TEA

330100107 ORNAMENTAL LAWNS (foliar treatment) Acid and TEA

330100207 ORNAMENTAL LAWNS (soil and foliar treatment) TEA

320000208 ORNAMENTAL PLANTS (soil treatment) BEE, TEA

350000107 ORNAMENTAL TREES (soil, plant bed, stump, basal bark, and foliar treatment) TEA

350002502 ORNAMENTAL TREES (stump, trunk and foliar treatment) Acid and TEA

330080207

ORNAMENTAL TURF FESCUE (athletic fields, cemeteries, golf courses, sod farms, 

rights of way, lawns, ornamental turf, parks, industrial, recreation areas as soil and 

foliar treatment and also as a seed treatment)

TEA

330080113 ORNAMENTAL TURF (commercial and golf course as foliar treatment) Acid, BEE and TEA

330081601 ORNAMENTAL TURF (sod farms) Acid, BEE and TEA

320010105 ORNAMENTAL WOODY PLANTS (bark, foliar, stump treatment) Acid, BEE and TEA

320012302 ORNAMENTAL WOODY PLANTS (injection treatment) TEA

340040108 ORNAMENTAL WOODY SHRUBS (foliar and soil treatment and plant beds) TEA

670110106 PARKING AREAS (FOLIAR TREATMENT) TEA

670020012 PARKS (soil treatment) TEA

670020103 PARKS (FOLIAR TREATMENT) BEE only
95

220250101

PASTURES (bahiagrass, Bermuda grass, bluegrass, fescue, orchardgrass, ryegrass, 

timothy, wheatgrass in pastures as foliar or frill treatment and as a stump or tree 

injection treatment)

TEA, BEE 

220130106 PASTURES (grass as foliar treatment) Acid and TEA

670120002 PATHS (foliar and soil treatment) TEA

630030012 PATIOS (soil and foliar treatment) TEA

280160106 PEAS (FOLIAR TREATMENT) TEA

030088106 PECANS (SOIL FUMIGATION) TEA

331160102 PERENNIAL BLUEGRASS (foliar treatment) Acid and TEA

220350101 PERENNIAL RYEGRASS (for forage-foliar treatment) TEA

670090118 PETROLEUM PUMPING STATION (FOLIAR TREATMENT) TEA

670090117 PETROLEUM TANK FARM (FOLIAR TREATMENT) TEA

301030102 PINE and RED PINE (FOREST) (FOLIAR TREATMENT) BEE and TEA

030110201 PISTACHIO NUTS (SOIL TREATMENT) TEA

640020006 POLES/POSTS TEA

650316117 PONDS (SLOW FLOWING) (WATER TREATMENT) TEA

650316118 PONDS (STANDING) (WATER TREATMENT) TEA

650316209 PONDS (SURROUNDING VEGETATION) Acid and TEA

650316110 PONDS (WATER TREATMENT) TEA

352560103 POST OAK (FOLIAR TREATMENT) BEE only

140130106 POTATOES (FOLIAR TREATMENT) TEA

140130406 POTATOES (SEED CROP FOLIAR TREATMENT) TEA

670050102 RAILROADS (FOLIAR TREATMENT) TEA and BEE

280450106 RANGELAND (FOLIAR TREATMENT) Acid and TEA

280452301 RANGELAND (Frill, foliar, stump, tree injection, and soil treatments) TEA, BEE

270170101 RAPESEED (OIL CROP) (FOLIAR TREATMENT) TEA

670020101 RECREATIONAL AREAS outdoor (foliar and soil treatment) TEA and BEE

650316128 RECREATIONAL WATERS (WATER TREATMENT) Acid and TEA

330450107 RED FESCUE (FOLIAR TREATMENT) BEE and TEA

330451601 RED FESCUE (GROWN FOR SOD) BEE and TEA

352040102 RED MAPLE (FOLIAR (TEA) or BARK (BEE) TREATMENT) TEA and BEE

350910101 RED OAK (FOLIAR (TEA) or BARK (BEE) TREATMENT) TEA and BEE

351060107 RED PINE (FOLIAR TREATMENT) BEE and TEA

301030102 RED PINE (FOREST) (FOLIAR TREATMENT) BEE and TEA

650006103 RESERVOIR WATER (UNSPECIFIED AND BANKS) Acid and TEA

680020103 RESIDENTIAL AREAS (foliar and injection treatments) TEA
96

240040106 RICE (FOLIAR TREATMENT) Acid and TEA

240040206 RICE- dry seeded, Ratoon , Beds, Water treatments ) TEA

240040108 RICE (WATER SEEDED) (foliar treatment) Acid and TEA

240040202 RICE (WATER SEEDED) (soil treatment) TEA

670130301 RIGHT-OF-WAYS communication and highway, (water, foliar, frill injection 

treatments, stump injection (BEE))

TEA and BEE

670060104 RIGHTS-OF-WAY communication and highway, (water, foliar, injection treatments) Acid, TEA and BEE 

670060006 RIGHTS-OF-WAY (PIPELINE) TEA

670060105 RIGHTS-OF-WAY (PIPELINE) (FOLIAR TREATMENT) Acid, TEA and BEE

670062304 RIGHTS-OF-WAY (PIPELINE) (FRILL TREATMENT) TEA

670062504 RIGHTS-OF-WAY (PIPELINE) (STUMP TREATMENT) Acid and TEA

670062307 RIGHTS-OF-WAY (PIPELINE) (TREE INJECTION TREATMENT) TEA

670060103 RIGHTS-OF-WAY (POWER LINES) (FOLIAR TREATMENT) Acid and TEA

670062303 RIGHTS-OF-WAY (POWER LINES) (Frill, Stump, Tree injection treatment) TEA

670050101 RIGHTS-OF-WAY (RAILROAD) (FOLIAR TREATMENT) Acid, BEE and TEA

670052301 RIGHTS-OF-WAY (RAILROAD) (FRILL TREATMENT) TEA

670052302 RIGHTS-OF-WAY (RAILROAD) (INJECTION TREATMENT) TEA

670052501 RIGHTS-OF-WAY (RAILROAD) (STUMP TREATMENT) TEA

670132501 RIGHTS-OF-WAY (STUMP TREATMENT) Acid and TEA

670060114 RIGHTS-OF-WAY (UTILITY) (FOLIAR TREATMENT) Acid, TEA and BEE

670062301 RIGHTS-OF-WAY (UTILITY) (FRILL TREATMENT) TEA

670062501 RIGHTS-OF-WAY (UTILITY) (STUMP TREATMENT) TEA

670062306 RIGHTS-OF-WAY (UTILITY) (TREE INJECTION TREATMENT) TEA

650326109 RIVERS (SLOW FLOWING) (WATER TREATMENT) TEA

650326101 RIVERS (WATER TREATMENT) TEA

650136102 ROADSIDE DITCHES TEA

670040102 ROADSIDES (FOLIAR TREATMENT) Acid, TEA and BEE

670042302 ROADSIDES (Frill, Injection, soil, stump treatment) TEA and BEE

240050106 RYE (FOLIAR TREATMENT) TEA

330490000

RYEGRASS (athletic fields, cemeteries, golf courses, sod farms, rights of way, lawns, 

ornamental turf, parks, industrial, recreation areas as soil and foliar treatment and also 

as a seed treatment)

BEE and TEA

330490108 RYEGRASS (ORNAMENTAL TURF) (FOLIAR TREATMENT) Acid and TEA

330430106 RYEGRASS (PERENNIAL) (FOLIAR TREATMENT) Acid and TEA

270080106 SAFFLOWER (FOLIAR TREATMENT) TEA

351110106 SASSAFRAS (FOLIAR and Dormant TREATMENT) BEE only

330980102 SEASHORE PASPALUM (ORNAMENTAL TURF) (FOLIAR TREATMENT) BEE and TEA
97

330310127

SHEEP FESCUE (athletic fields, cemeteries, golf courses, sod farms, rights of way, 

lawns, ornamental turf, parks, industrial, recreation areas as soil and foliar treatment 

and also as a seed treatment)

TEA

330310113 SHEEP FESCUE (FOLIAR TREATMENT) Acid and TEA

670110009 SIDEWALKS TEA

670110104 SIDEWALKS (FOLIAR TREATMENT) TEA

240060107 SORGHUM (GRAIN) (FOLIAR TREATMENT) TEA

240060103 SORGHUM (MILO) (FOLIAR TREATMENT) TEA

280230106 SOYBEANS (FOLIAR TREATMENT) TEA

351160105 SPRUCE (FOLIAR TREATMENT) BEE and TEA

300640101 SPRUCE (FOREST) (FOLIAR TREATMENT) TEA

300640201 SPRUCE (FOREST) (SOIL TREATMENT) BEE and TEA

330500108 ST. AUGUSTINEGRASS (Foliar treatment on lawns and sod farms and foliar or soil 

treatment on ornamental turf)

TEA

650336105 STANDING WATER TEA

650336106 STANDING WATER (MARGINS) TEA

770040003 STORAGE AREAS TEA

670090102 STORAGE YARDS (foliar, frill, stump, and tree injection treatments) TEA

010160106 STRAWBERRIES (FOLIAR TREATMENT) TEA

650326110 STREAMS (SLOW FLOWING) (WATER TREATMENT) TEA

650326104 STREAMS (WATER TREATMENT) TEA

300002501 STUMPS TEA

280200106 SUGAR BEETS (FOLIAR TREATMENT) TEA

351170106 SUGAR MAPLE (FOLIAR TREATMENT) TEA

342750101 SUMAC (foliar and Dormant Treatment) BEE only

270110102 SUNFLOWER (FOLIAR TREATMENT) TEA

650336205 SWAMPS (foliar and water treatment) TEA

650336206 SWAMPS/MARSHES/BOGS/STANDING WATER (VEGETATION) (FOLIAR 

TREATMENT)

TEA

351180106 SWEETGUM (FOLIAR TREATMENT) TEA

330310116

TALL FESCUE (athletic fields, cemeteries, golf courses, sod farms, rights of way, 

lawns, ornamental turf, parks, industrial, recreation areas as soil and foliar treatment 

and also as a seed treatment)

Acid and TEA 

330511601 TALL FESCUE (GROWN FOR SOD) BEE

330510103 TALL FESCUE (LAWNS) (FOLIAR TREATMENT) BEE

330510102 TALL FESCUE (ORNAMENTAL TURF) (FOLIAR TREATMENT) Acid, BEE and TEA

670090107 TANK FARMS (foliar treatment and soil treatment (BEE only)) TEA and BEE

670120005 TRAILS TEA
98

670120105 TRAILS (Foliar or Stump treatment) TEA

670060101 UTILITY (RIGHTS-OF-WAY) (FOLIAR TREATMENT) TEA

680020004 VACANT LOTS TEA

670000103 VACANT LOTS (FOLIAR TREATMENT) TEA

280240206 VEGETABLE CROPS (SOIL TREATMENT) BEE only

670120107 WALKS (BRICK) (FOLIAR TREATMENT) TEA

670120109 WALKS (foliar or soil treatment) TEA

680000102 WASTELAND (FOLIAR TREATMENT) TEA

650156104 WATER (POTABLE) TEA

650336202 WETLANDS Acid and TEA

650336202 WETLANDS (STUMP TREATMENT) Acid ONLY

650336202 WETLANDS (TREE INJECTION TREATMENT) Acid ONLY

220070106 WHEAT (FORAGE) (FOLIAR TREATMENT) TEA

352480102 WHITE BIRCH (FOLIAR TREATMENT) TEA

352300101 WHITE OAK (FOLIAR (TEA) or BARK (BEE) TREATMENT) TEA and BEE

351260106 WHITE PINE (FOLIAR TREATMENT) TEA

301350101 WHITE PINE (FOREST) (Foliar or Soil TREATMENT) TEA and BEE

010140103 WILD GRAPES (FOLIAR TREATMENT) BEE Only

640020025 WOOD FENCE POSTS TEA

010140103 WILD GRAPES (FOLIAR TREATMENT) BEE ONLY

680010102 WOODLAND AREAS (FOLIAR TREATMENT) TEA

343880104 YAUPON tree (bark treatment) BEE only

341430000 YUCCA BEE only

330560000 ZOYSIAGRASS (soil and foliar treatments, athletic fields, cemeteries, golf courses, 

sod farms, lawns, ornamental turf, parks)

TEA and BEE

330560109 ZOYSIAGRASS (foliar treatment lawns and ornamental lawns) Acid and TEA
99

Appendix D 

Endangered Species 

Based on this screening-level assessment, there are potential risks of direct effects to 

listed taxa from the use of Triclopyr TEA and Triclopyr BEE on some of their registered 

use sites. Listed species of these taxa may also be affected through indirect effects 

because of the potential direct effects on listed and non-listed species. Potential direct 

effects on listed species from the use of Triclopyr products may be associated with 

modification of primary constituent elements of designated critical habitats, where such 

designations have been made. However, at this current stage of the Registration Review 

process, it is premature to make effects determinations for listed species until further 

refinements are conducted. To make effects determinations for individual species, useful 

refinements may include analyses of 1) more detailed, species-specific ecological and 

biological data; 2) more detailed and accurate information on Triclopyr use patterns; and 

3) sub-county level spatial proximity data for the co-occurrence of potential effects areas 

and listed species and any designated critical habitat. Examples of such refinements are 

described below. 

EFED is currently developing tools that are expected to further refine the assessment and 

are designed to support effects determinations for individual federally listed species and 

their designated critical habitats (where applicable). Scientific information obtained from 

the U.S. Fish & Wildlife Service (USFWS), the National Marine Fisheries Service 

(NMFS), and other reliable sources is being collated by EFED to address all currently 

listed species. The information will be stored in an Office of Pesticide Programs 

Pesticide Registration Information SysteM (PRISM) knowledgebase. The listed species 

knowledgebase will consist of an information repository that houses biological and 

behavioral information relevant to individual species (e.g., habitat, diet, and life history, 

including specific temporal and spatial associations) and a document repository that 

contains supporting documents (e.g., USFWS recovery plans) and electronic information 

(e.g., GIS data files). For terrestrial taxa, the biological information relevant to risk 

quotient (RQ) calculations (e.g., diet and body weight) will be used to parameterize 

exposure estimates to derive species-specific RQs using a method consistent with 

currently used methods in the T-REX and T-HERPS models. 

Refinements may also include more detailed analyses of the registered uses and their use 

patterns that result in LOC exceedances for federally listed species in the screening-level 

assessment. The analyses may include more information on where, when, and how 

Triclopyr is used on all use sites. Actual usage data (when available) and national landcover datasets that indicate potential use sites [e.g., national land cover dataset (NLCD), 

crop data layer (CDL)] may be used to support a more refined analysis of where triclopyr 

products are reasonably expected to be used. Similarly, refinements for the timing of 

applications and how triclopyr products are used may be based on the analysis of 

additional usage data, beyond what were available at the time of the screening-level 

assessment, and a more in-depth exploration of agronomic practices. 

The U.S. Environmental Protection Agency, along with the U.S. Department of 

Agriculture (USDA), the U.S. Fish and Wildlife Service (FWS), and the National Marine 
100

Fisheries Service (NMFS), have announced the availability of a report developed by the 

National Academy of Sciences’ National Research Council outlining recommendations 

on specific scientific and technical issues related to the development of endangered and 

threatened species risk assessments for pesticides that are compliant with the Endangered 

Species Act (ESA) and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). 

The EPA, USDA, FWS and NMFS asked the NRC to consider a range of scientific and 

technical issues including: 

• identifying best available scientific data and information; 

• considering sub-lethal, indirect and cumulative effects; 

• assessing the effects of chemical mixtures and inert ingredients; 

• analyzing the effects of pesticide use through the use of models; 

• incorporating uncertainties into the evaluations; and 

• using geospatial information and datasets that can be employed by the agencies in 

the course of these assessments. 

After reviewing the NRC’s recommendations on these scientific and technical issues, the 

EPA and its federal partners will determine how these recommendations can be 

implemented and incorporated into the scientific approaches for developing listed species 

risk assessments. It is anticipated that any draft guidance and/or science policies 

developed by EPA and its federal partners as a result of the NAS recommendations 

would be released for public comment prior to implementation. 

The refinements based on individual species data; additional, detailed usage information, 

when available; and further recommendations from the NRC report are expected to help 

to more accurately identify potential areas of effect and to better inform effects and 

habitat determinations for listed species and any designated critical habitats. For 

example, if Triclopyr is used when a particular species of concern is not present (e.g., it is 

migratory) or is not co-located in space, then risk of potential direct effects to the species 

may often be precluded. If LOCs are still exceeded for monocots, mammals, freshwater 

invertebrates, estuarine/marine invertebrates, and freshwater fish after conducting the 

refined analyses, further analyses of the potential spatial and temporal co-occurrence of 

listed species of concern (and any designated critical habitat) may be conducted. The 

extent of possible refinement in the analyses of spatial/temporal co-occurrence will 

largely depend on the scale and quality of the available sub-county level use site (e.g., 

NLCD, CDL) and species location data. 

APPENDIX E 

ENDOCRINE DISRUPTOR SCREENING PROGRAM: 

As required under FFDCA section 408(p), EPA has developed the Endocrine Disruptor 

Screening Program (EDSP) to determine whether certain substances (including pesticide 

active and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a “naturally occurring estrogen, or other such endocrine effects as the 

Administrator may designate.” The EDSP employs a two-tiered approach to making the 

statutorily required determinations. Tier 1 consists of a battery of 11 screening assays to 

identify the potential of a chemical substance to interact with the estrogen, androgen, or 

thyroid (E, A, or T) hormonal systems. Chemicals that go through Tier 1 screening and 
101

are found to have the potential to interact with E, A, or T hormonal systems will proceed 

to the next stage of the EDSP where EPA will determine which, if any, of the Tier 2 tests 

are necessary based on the available data. Tier 2 testing is designed to identify any 

adverse endocrine related effects caused by the substance, and establish a dose-response 

relationship between the dose and the E, A, or T effect. 

Between October 2009 and February 2010, EPA issued test orders/data call-ins for the 

first group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert 

ingredients. This list of chemicals was selected based on the potential for human 

exposure through pathways such as food and water, residential activity, and certain postapplication agricultural scenarios. This list should not be construed as a list of known or 

likely endocrine disruptors. 

Triclopyr is not on List 2. List 2 represents the next set of chemicals for which EPA 

intends to issue test orders/data call-ins in the near future. “ For further information on 

the status of the EDSP, the policies and procedures, the lists of chemicals, future lists, the 

test guidelines and the Tier 1 screening battery, please visit our website.6

 

6 http://www.epa.gov/endo/

Welcome to the EFED 

Screening Tool for Inhalation Risk

This tool is designed to provide the risk assessor with a rapid method for determining 

the potential

significance of the inhalation exposure route to birds and mammals in a risk 

assessment.

Input

Application and Chemical Information

Enter Chemical Name Triclopyr Acid

Enter Chemical Use Turf

Is the Application a Spray? (enter y or n) y

If Spray What Type (enter ground or air) ground

Enter Chemical Molecular Weight (g/mole) 256.5

Enter Chemical Vapor Pressure (mmHg) 1.30E-06

Enter Application Rate (lb a.i./acre) 12

Toxicity Properties

Bird
102

 

Enter Lowest Bird Oral LD50 (mg/kg bw) 1698

Enter Mineau Scaling Factor 1.15

Enter Tested Bird Weight (kg) 1.58

Mammal

Enter Lowest Rat Oral LD50 (mg/kg bw) 630

Enter Lowest Rat Inhalation LC50 (mg/L) 2.6

Duration of Rat Inhalation Study (hrs) 4

Enter Rat Weight (kg) 0.35

Output

Results Avian (0.020 kg )

Maximum Vapor Concentration in Air at Saturation mg/m3) 1.79E-02

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.26E-03

Adjusted Inhalation LD50 2.82E+01

Ratio of Vapor Dose to Adjusted Inhalation LD50 8.01E-05 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 1.27E+00

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD50 4.50E-02 Exposure not Likely Significant

Results Mammalian (0.015 kg )

Maximum Vapor Concentration in Air at Saturation (mg/m3) 1.79E-02

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.84E-03

Adjusted Inhalation LD50 1.55E+02

Ratio of Vapor Dose to Adjusted Inhalation LD50 1.83E-05 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 1.59E+00

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD50 1.03E-02 Exposure not Likely Significant

 SIPS Model 

Table 1. Inputs

Parameter Value

Chemical name Triclopyr Acid

Solubility (in water at 25oC; mg/L) 440

Mammalian LD50 (mg/kg-bw) 630

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian species

Mammalian NOAEL (mg/kg-bw) 25

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian species

Avian LD50 (mg/kg-bw) 1698

Avian test species mallard duck

Body weight (g) of "other" avian species

Mineau scaling factor 1.15
103

 

Mallard NOAEC (mg/kg-diet) 100

Bobwhite quail NOAEC (mg/kg-diet) 500

NOAEC (mg/kg-diet) for other bird species

Body weight (g) of other avian species

NOAEC (mg/kg-diet) for 2nd other bird species

Body weight (g) of 2nd other avian species

Table 2. Mammalian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 75.6800 75.6800

Adjusted toxicity value (mg/kg-bw) 484.5712 19.2290

Ratio of exposure to toxicity 0.1562 3.9357

Conclusion*

Exposure through drinking 

water alone is a potential 

concern for mammals

Exposure through drinking 

water alone is a potential 

concern for mammals

Table 3. Avian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 356.4000 356.4000

Adjusted toxicity value (mg/kg-bw) 881.6447 4.9613

Ratio of exposure to acute toxicity 0.4042 71.8366

Conclusion*

Exposure through drinking 

water alone is a potential 

concern for birds

Exposure through drinking 

water alone is a potential 

concern for birds

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when aggregated with other 

routes (i.e., diet, inhalation, dermal), pesticide exposure through drinking water may contribute to a total exposure that has potential for effects

to non-target animals.