Page 3 of 111

Table of Contents

1. Executive summary................................................................................................................. 4

2. Introduction............................................................................................................................. 7

3. Use Characterization............................................................................................................... 8

4. Conclusions from Previous Risk Assessments..................................................................... 11

4.1. Ecological Risk Assessment ................................................................................................. 11

4.2. Drinking Water Exposure Assessments......................................................................... 12

4.3. Clean Water Act Programs............................................................................................. 13

5. Environmental Fate and Transport........................................................................................ 13

6. Receptors............................................................................................................................... 17

6.1. Effects to Aquatic Organisms ........................................................................................ 17

6.2. Effects to Terrestrial Organisms .................................................................................... 22

6.3. Ecological Incidents....................................................................................................... 27

7. Exposure Pathways of Concern ............................................................................................ 31

8. Analysis Plan ........................................................................................................................ 32

8.1. Stressors of Concern....................................................................................................... 32

8.2. Measures of Exposure .................................................................................................... 33

8.3. Measures of Effect ......................................................................................................... 35

9. Endangered Species Assessments...................................................................................... 35

10. Endocrine Disruptor Screening Program ....................................................................... 36

11. Preliminary Identification of Data Gaps ........................................................................ 37

11.1. Environmental Fate..................................................................................................... 37

11.2. Effects......................................................................................................................... 39

12. References............................................................................................................................. 43

Appendix A- OPPIN Bibliography........................................................................................... 45

Appendix B: Toxicity Comparison for Picloram Potassium Salt, 2,4-D TIPA Salt and 

Formulations Containing Both Picloram TIPA Salt and 2,4-D TIPA Salt............................. 100

Appendix C: Summary Data for Picloram Related Incidents (PC Codes 005101, 005102, 

005104) ................................................................................................................................... 102

Appendix D- SIP and STIR Outputs........................................................................................... 108
Page 4 of 111

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 picloram. This action includes 

triisopropanolamine picloram (TIPA-salt), potassium picloram (K-salt), and picloram acid 

(picloram). Isooctyl/ethylhexyl picloram is not included in this action as there are no current 

registrations for the active ingredient. The problem formulation describes the methods planned 

to be used 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 picloram as well as uncertainties unique to the risk 

assessment of picloram. 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 data gaps exist for picloram: 

• Adsorption/Desorption (OCSPP Guideline 835.1230): Accurate quantification of 

sorption coefficients is highly important for a compound with high expected mobility. 

Current reported estimates are derived from Footprint, a database associated with the 

European Food Safety Administration for which the supporting data are not available.

• Prospective Groundwater Study (OCSPP Guideline 835.7100): The leaching of 

picloram to groundwater and the subsequent use of that groundwater is a complete 

exposure pathway with effects to non-target plants and five reported incidents. The 

veracity of these incidents is confirmed by comparing a screening level groundwater 

concentration from PRZM-GW of 0.421 mg a.e./L to the most sensitive available 

terrestrial plant endpoint (vegetative vigor tomato NOAEC = 0.00016 lb a.e./ac) . Less 

than 1/500th of an inch of irrigation water would be required to reach this endpoint. 

Furthermore, less than one inch of irrigation water would be required to reach the vast 

majority of reported terrestrial plant endpoints. A prospective groundwater study 

performed in an area representative of typical picloram use conditions would allow for 

better characterization of expected groundwater concentrations and may demonstrate 

potential mitigations such as well setback distances or minimum well depths. Terrestrial 

field dissipation studies only characterize dissipation up to 60 inches below the surface 

and cannot effectively inform these mitigation decisions. 

• Environmental Chemistry Methods and Independent Laboratory Validation on 

Soil, Water, and Compost (OCSPP Guideline 850.6100): Pending review of 

environmental chemistry methods on soil and water (MRIDs 45366 and 69078), the data 

is requested. Data is also requested for environmental chemistry methods on compost 

and independent laboratory validation of soil, water, and compost. For compost, methods 

should be derived that can be used with equipment found in state laboratories and use 

laboratory standards that can be readily obtained. LOQs for ECMs need to be low 

enough to detect residues that could cause a risk concern (i.e. need to be below the most 

sensitive toxicity endpoints reported in this document).

• Dissipation study in compost (Non-Guideline): The application of picloram to 

vegetative matter that is subsequently used as compost or animal feed has been found to 

retain picloram residues and affect non-target plants (see Section 6.3). This route of 
Page 5 of 111

exposure is common across the picolinc acid herbicides (aminopyralid, clopyralid, and 

picloram). A study is requested to demonstrate the rates of degradation and leaching in 

vegetative and manure composts. The study will be used to characterize this risk from 

picloram residues in compost and may demonstrate potential mitigations such as compost 

holding times. It is requested that a study protocol is submitted for review before the 

study is conducted. Through the SFIREG Pesticides Operations & Management 

committee on September 16, 2013, it was made known that Dow AgroSciences is

developing a molecular imprinted polymer for solid phase extraction that could be used 

for detecting picloram in compost. It was expected that a method could be released to 

state laboratories by April 2014. A compost dissipation study would be instrumental in 

interpreting the monitoring data that will become available after this method is 

disseminated. 

The following ecological data gaps exist for picloram:

• Estuarine/Marine Invertebrate Chronic Toxicity Study (OCSPP Guideline 

850.1350): Picloram has outdoor uses that may result in exposure to estuarine/marine 

invertebrates. In the absence of data EPA will use an acute to chronic ratio (ACR) for the 

freshwater invertebrate and apply that to the lower bound of the acute estuarine/marine 

data to estimate a chronic endpoint for the estuarine/marine invertebrate. Although 

according to CFR 158 the lack of this study is considered a data gap, the utility of a new 

estuarine/marine invertebrate life cycle study for the risk assessment is considered low

given the predicted difference between the exposure estimates from the RED and the 

toxicity estimate derived using the ACR approach in this document. Therefore, a new 

estuarine/marine invertebrate life cycle test is not requested.

• Estuarine/Marine Fish Early-Life Stage Toxicity Study (OCSPP Guideline 

850.1400): An estuarine/marine fish early life-stage test using the TGAI has not been 

submitted, since it was not considered to be necessary based on previous risk assessments 

for picloram. In the absence of data EPA will use an ACR from the rainbow trout acute 

and chronic data with picloram acid and apply that to the acute estuarine/marine data 

point values to estimate a chronic endpoint for saltwater fish. Although according to 

CFR 158 the lack of this study is considered a data gap, the utility of a new 

estuarine/marine fish ELS study for the risk assessment is considered low at this time, 

given the predicted difference between the exposure estimates from the RED and the 

toxicity estimate derived using the ACR approach in this document. Therefore, a new 

saltwater early life stage toxicity test is not requested.

• Algal Toxicity Study (OCSPP Guideline 850.4500). No data is available for the 

estuarine/marine diatom for picloram acid or the TIPA or potassium salts. Since the 

freshwater diatom was the most sensitive taxa tested for the TIPA salt, a study on 

estuarine/marine diatoms is required for this ai. A new study is not required for the acid 

or potassium salt.
Page 6 of 111

• Acute Avian Oral Toxicity Study (OCSPP Guideline 850.2100): No data is available 

for passerine species, which may be more sensitive than the tested mallard and bobwhite 

species. Although the LD50 and LC50 data for the mallard and bobwhite were all 

nondefinitive (“greater than”) values, there were sublethal effects in the acute oral 

mallard study with picloram acid and treatment related mortalities in the acute dietary 

bobwhite study with picloram potassium salt. Therefore, a passerine study is required 

using either the acid or the potassium salt. A protocol should be submitted to the 

Agency, prior to study initiation. 

• Chronic Avian Reproduction Study (OCSPP Guideline 850.2300): No data is 

available for chronic effects to birds from picloram use. Therefore, a chronic study is 

required using either picloram acid or the potassium salt. Although the LD50 and LC50

data for the mallard and bobwhite were all nondefinitive (“greater than”) values, there 

were sublethal effects in the acute oral mallard study with picloram acid and treatment 

related mortalities in the acute dietary bobwhite study with picloram potassium salt. 

Since the dietary study exposure is more similar to a chronic exposure than the acute oral 

study exposure, it is recommended that the chronic study be conducted with the 

bobwhite. 

• Terrestrial Plant Seedling Emergence and Vegetative Vigor Tier II Studies (OCSPP 

Guidelines 850.4100 and 850.4150): A previously submitted study (MRID 41296501) 

used to support the registration of the TIPA salt was downgraded to supplemental--

qualitative. Therefore, no quantitatively acceptable data is available for picloram’s effect 

to terrestrial plants from the TIPA salt formulation. The most sensitive species (for 

dicots: tomato, drybean and soybean. For monocots: onion and wheat) as indicated in the 

currently available data should be tested with the TIPA salt formulation.

• Data Gaps for products containing picloram combined with other herbicides

A number of end-use products contain picloram in combination with another 

herbicide (i.e. 2,4-D, dicamba, fluroxypyr and/or triclopyr). Since these products 

are labeled for aerial application, there exists the potential for spray drift to nontarget plants. Therefore, these data are needed to conduct a risk assessment:

• Terrestrial plant vegetative vigor (850.4150) and seedling emergence (850.4100) 

tests using the most sensitive dicot and monocot species: tomato, drybean, 

soybean, onion and wheat using TEP.

The preceding studies with TEP are a subset of what is required to support the existing

use pattern according to the 40 CFR Part 158 and were identified because they resulted in 

the most sensitive endpoints for picloram and terrestrial plants appeared to be more 

sensitive to a multi ai formulation containing picloram TIPA salt and 2,4-D TIPA salt 

than to either a.i. alone (using picloram K salt as a surrogate for the picloram TIPA salt 

and 2,4-D DMA salt as a surrogate for 2,4-D TIPA salt due to a lack of terrestrial plant 

data on formulations containing only one TIPA salt). For the preceding studies where 

EFED is requesting data on TEP, data are needed on a representative product that 

contains both picloram and the additional ai(s). When there are multiple products with 

dual active ingredients, as is the case for the picloram and 2,4-D a.i.’s, the representative 

TEP used is normally the product with the highest percentages of active ingredient and/or

is expected to result in the highest toxicity. 

Major uncertainties:
Page 7 of 111

Major toxicological data gaps primarily affect the risk assessment for direct effects to aquatic 

and terrestrial plants, as these taxa were the main risk concerns previously identified for this 

chemical and quantitatively acceptable data is missing, especially for the picloram TIPA salt 

formulation’s effects to terrestrial plants. Spray drift damage to non-target plants from picloram 

formulations is of particular concern for this chemical. In addition to the lack of information for 

effects of the picloram TIPA salt formulation (usually co-formulated with the 2,4-D TIPA salt), 

there is also a lack of toxicity information for formulations with multiple a.i.’s, especially where 

those formulations may be applied aerially. Multiple a.i. formulations other than those with 2,4-

D that are applied aerially and have higher potential for spray drift damage to non-target 

organisms include those with picloram TIPA salt and dicamba (e.g. Trooper Extra, PD-2, Grazon 

PD2), picloram TIPA salt and fluroxypyr 1-methylheptyl ester (e.g. Trooper Pro, Surmount), 

picloram K salt and triclopyr (e.g. GF-1249). The absence of information on picloram TIPA 

salt’s (as well as the multiple a.i.formulations’) toxicity to plants prohibits quantitative 

assessment of the potential risk to nontarget plants posed by the application of these products. 

A significant uncertainty regarding environmental fate is picloram’s behavior in compost. 

Degradation and dissipation processes differ in compost as compared to guideline environmental 

fate studies. An improved environmental chemistry method and a compost dissipation study are 

needed to better characterize this pathway. The absence of information on the persistence of 

picloram residues in composted plant material or animal manure prohibits a quantitative 

assessment of the potential risk to nontarget taxa posed by the application of composted material 

containing these residues. Without information on the fate of picloram residues in these media, 

the risk assessment will only be able to qualitatively address risk to nontarget taxa where plants 

from treated areas or manure from animals fed on treated plants is used.

2. Introduction

Picloram is a systemic herbicide that acts as a plant growth regulator by mimicking naturally 

occurring plant growth hormones called auxins. Tomlin (2004) indicates that it has effects on 

broad-leaf plants, but not grasses, with the exception of some seedlings. Picloram disrupts 

normal plant growth by binding to molecules that are normally used as receptors by auxins. 

Because picloram is more persistent in plants than auxins, the binding causes abnormal growth 

and leads to plant death (Tu et al., 2001). Picloram and other herbicides in the pyridine 

carboxylic acid chemical family (e.g., clopyralid and aminopyralid) can act at multiple sites in a 

plant and disrupt hormone balance and protein synthesis, the metabolic pathways that affect plant 

growth. Picloram and other members of the pyridine carboxylic acid family are systemic and can 

move in both the xylem and the phloem to areas of new plant growth (meristematic tissues). 

Picloram uptake is primarily through the foliage, but root uptake is possible. 

The use information presented in this problem formulation was obtained from the tables in the 

EFED Label Data Report dated 7/18/2013, from BEAD’s Chemical Profile for Registration 

Review (USEPA, 2013), and from various evaluated labels. There are currently 9 Section 3 

registered products for picloram acid, 15 Section 3 registered products for picloram 
Page 8 of 111

triisopropanolamine salt, and 10 Section 3 registered products for picloram potassium salt. 

There are no Special Local Needs (SLN) registrations for picloram.

The following labeling statements appear on all picloram labels to avoid contamination of

compost, aquatic environments and drinking water from use on agricultural products. Label 

language was determined to be necessary due to composting and irrigation water incidents.

ENVIRONMENTAL HAZARD STATEMENTS 

This pesticide is toxic to some plants at very low concentrations. Non-target plants may 

be adversely affected if pesticide is allowed to drift from areas of application. Do not 

apply directly to water, or to areas where surface water is present, or to intertidal areas 

below the mean high water mark. Do not contaminate water when disposing of 

equipment washwaters. Do not contaminate water used for irrigation or domestic 

purposes by cleaning of equipment or disposal of wastes or rinsate. Do not allow 

runoff or spray to contaminate wells, irrigation ditches or any body of water used for 

irrigation or domestic purposes. Do not make application when circumstances favor 

movement from treatment site. 

This chemical is known to leach through soil into groundwater under certain conditions 

as a result of agricultural use. Use of this chemical in areas where soils are permeable, 

particularly where the water table is shallow, may result in groundwater contamination. 

This chemical can contaminate surface water through spray drift. Under some conditions, 

picloram may also have a high potential for runoff into surface water (primarily via 

dissolution in runoff water), for several months post-application. These include poorly 

draining or wet soils with readily visible slopes toward adjacent surface waters,

frequently flooded areas, areas over-laying extremely shallow groundwater, areas with infield canals or ditches that drain to surface water, areas not separated from adjacent 

surface waters with vegetative filterstrips, and areas over-laying tile drainage systems that 

drain to surface water.

3. Use Characterization

Picloram is a systemic herbicide used for control of woody plants and a wide range of broadleaf

weeds in range management programs. It is registered for use on agricultural crop soils for the 

following: barley, fallow, oats, wheat, pastureland, and forestry. It is also registered for use on 

conservation reserve program land, non-agricultural sites, rights-of-way, industrial sites, storage 

yards, fencerows, industrial storage areas, and hedgerows. Picloram is formulated as 

emulsifiable, soluble concentrate, and as a solution-ready-to-use. Picloram can be applied by 

broadcast, spot treatment as foliar (leaf), bare soil spray, as a basal bark treatment, and/or by air 

as broadcast spray. The chemical profile produced by BEAD, located in the docket, lists the use 

patterns of maximum exposures for the current uses of picloram. The most dominant use is on 

pastureland representing 98% of usage between 1998 and 2011. From 2007-2011, the annual 
Page 9 of 111

total agricultural usage averaged approximately 810,000 pounds acid equivalent (lbs a.e.) for 5.3 

million acres. On average, the states with the most agricultural usage in terms of pounds a.e. 

applied are Texas (26%), Oklahoma (12%), and Arkansas (10%), and the top states in terms of 

the total area treated are Texas (31 %), same percentage for Oklahoma (12%), and Arkansas 

(9%). Usage information for non-agricultural uses is not reported. The absence of this information is 

a significant uncertainty especially considering the broad spectrum of non-agricultural uses.

Labels for use in forests, conifers, and rooftops do not specify maximum seasonal application 

rates or a maximum number of applications per year. A forest dissipation study indicates an 

exposed soil dissipation half-life of 34 days, therefore applications of picloram several times per 

year would not be unreasonable. Without clarification of the labels or details on usage in forests 

and conifers, conservative assumptions will be made. Conservative assumptions will also be 

made for number of roof top applications per year in the absence of usage information or 

clarification of the labels. All broadcast applied uses may be applied aerially.

The following tables summarize use patterns for picloram acid (PC code 005101; MW: 241.5 

g/mol ), the TIPA-salt of picloram (PC code 005102; MW: 432.6 g/mol), and the K-salt of 

picloram (PC code 005104; MW: 280.6 g/mol). Though these are three distinct chemical 

moieties, they will be assessed together using the acid equivalence (a.e.) method. That is, only 

the picloram acid component will be assessed and the application rates of the TIPA-salt and the 

K-salt will be adjusted to account for only picloram acid. For instance the 1.939 lbs a.i./acre

maximum application rate for the TIPA salt will be converted to 1.085 lbs a.e./acre because only 

56% of the a.i. constitutes the a.e. in the case of the TIPA salt (241.5 g*mol-1/432.6 g*mol-1= 

56%).

Table 1. Label use information for picloram acid (PC Code 005101)

Use Site

Formula

tion 

Type

Max Rate (lbs 

a.e./Acre)

Max. 

No. of 

Apps 

per 

Year

Min. 

App. 

Interval

Application 

Methods Comments 

Single Annual

AGRICULTURAL 

FALLOW/IDLELAND 

/ CONSERVATION 

RESERVE

SC/L 0.514 1.932 NS 30 days Broadcast Preplant/Postplant

CONIFERS 

(PLANTATIONS/NU

RSERIES) SC/L 1.932 NS NS NS

Frill, Girdle, 

Stump, 

Broadcast, 

Band, High 

volume spray, 

Tree injection

FOREST TREES 

(ALL OR 

UNSPECIFIED) SC/L 1.932 NS NS 1 year

Frill, Girdle, 

Stump, 

Broadcast, 

Band, High 

volume spray, 

Tree injection

NONAGRICULTUR

AL UNCULTIVATED 

AREAS/SOILS SC/L 1.932 1.932 1 NS Broadcast

PASTURES SC/L 1.027 1.932 NS 30 day

Broadcast; 

high volume 

dilute spray

Preplant/Postplant

RANGELAND SC/L 1.027 1.932 NS 30 day

Broadcast; 

high volume 

dilute spray

Preplant/Postplant

SC- Suspended Concentrate
Page 10 of 111

L-Liquid 

NS-Not Specified

Table 2. Label use information for TIPA-salt of picloram (PC Code 005102)

Use Site

Formula

tion 

Type

Maximum Rate (lbs 

a.e./Acre)

Max. 

No. of 

Apps/

Year

Min. 

App. 

Inter

val

Application 

Methods Comments 

Single Annual

AGRICULTU

RAL 

FALLOW/IDL

ELAND / 

CONSERVAT

ION 

RESERVE

EC/SC/L 0.282 1.105 NS NS

Broadcast, 

Spot 

treatment, 

high volume 

spray

Preplant/Postplant

CONIFERS 

(PLANTATIO

NS/NURSERI

ES)

SC/L 1.082 NS NS NS Band 

treatment Thinning

FOREST 

TREES (ALL 

OR 

UNSPECIFIE

D)

RTU/SC/

L

1.082

2.064 

lbs/100 gal

1.133 NS 1 year

Frill, Girdle, 

Stump, 

Broadcast, 

High volume 

spray

NONAGRICU

LTURAL 

UNCULTIVAT

ED 

AREAS/SOIL

S

RTU/EC/

SC/L

1.938

2.064

lbs/100 gal

1.133 NS 1 year

Frill, Girdle, 

Stump, 

Broadcast, 

High volume 

spray

Restricted from 

Nassau and Suffolk 

Counties, New York

PASTURE

S SC/L/EC

0.565

1.334 lb 

a.i./100 

gallons

1.105 NS 30 

day

Broadcast; 

high volume 

dilute spray, 

spot treatment

Preplant/Postplant

RANGELA

ND SC/L/EC

0.565

1.334 lbs 

/100 gal

1.105 NS 30 

day

Broadcast; 

high volume 

dilute spray, 

spot treatment

Preplant/Postplant

ROOFS EC

0.665

2.23 lb / 100 

gal

NS NS NS

Broadcast, 

high volume 

spray

Weed 

postemergence

RTU – Ready to use

EC – Emulsifiable Concentrate

SC- Suspended Concentrate

L- Liquid 

NS-Not Specified

Table 3. Label use information for K-salt of picloram (PC Code 005104)

Use Site

Formula

tion 

Type

Max Rate (lbs a.e./Acre) Max. 

No. of 

Apps 

per 

Year

Min. 

App. 

Interv

al

Application 

Methods Comments 

Single Annual

AGRICULTU

RAL 

FALLOW/IDL

ELAND / 

CONSERVAT

ION 

RESERVE

EC/SC/L 1.029 NS NS 30 days Spot treatment

FOREST 

TREES (ALL 

OR 

UNSPECIFIE

D)

EC/SC/L 1.029 NS NS NS Broadcast

NONAGRICU

LTURAL 

UNCULTIVAT

EC/SC/L 1.029 1.029 NS NS Broadcast, 

Spot 

Restricted from 

Nassau and Suffolk 
Page 11 of 111

Use Site

Formula

tion 

Type

Max Rate (lbs a.e./Acre) Max. 

No. of 

Apps 

per 

Year

Min. 

App. 

Interv

al

Application 

Methods Comments 

Single Annual

ED 

AREAS/SOIL

S

treatment, 

high volume 

spray

Counties, New York

PASTURE

S EC/SC/L 1.029 1.029 NS NS

Broadcast, 

Spot 

treatment, 

high volume 

spray

RANGELA

ND EC/SC/L 1.029 1.029 NS NS

Broadcast, 

Spot 

treatment, 

high volume 

spray

RTU – Ready to use

EC – Emulsifiable Concentrate

SC- Suspended Concentrate

L- Liquid 

NS-Not Specified

4. Conclusions from Previous Risk Assessments

4.1. Ecological Risk Assessment 

The last ecological risk assessment conducted on picloram and its associated salts was the 1995 

RED (USEPA, 1995). The RED raised concerns for picloram’s risk of contamination of ground 

and surface water and damage to terrestrial nontarget plants adjacent to areas of application via 

runoff and drift and possibly from more distant areas where groundwater is used for irrigation 

water or discharged into surface water. 10 states had reported picloram detections in 

groundwater at the time of this risk assessment. Risks were not assessed quantitatively for 

nontarget organisms exposed via irrigation water.

In March 1985, the Agency issued a Registration Standard for picloram. This

document required additional data and imposed a maximum level of hexachlorobenzene (HCB)

in the technical product of 200 ppm. It also required testing for nitrosoamines. The sole

registrant of picloram has complied with these requirements; no nitrosoamines were detected

in picloram products (< 1 ppm) and the level of HCB, an impurity that results from the

manufacturing process, has been certified to be less than 100 ppm. The picloram Final

Reregistration Standard and Tolerance Reassessment (FRSTR) was issued 5/18/88.

Picloram and its two salts (as well as its ester, for which there currently are no active 

registrations) were considered to be similar to each other in their biological and chemical 

characteristics in the environment and were not distinguished in the fate review. The assessment 

noted the following data gaps for the TIPA and potassium salts: acute data for estuarine/marine 

fish, Tier 2 terrestrial seedling emergence and vegetative vigor for sensitive crops that had been 

reported in recent incident reports including for watermelon, tobacco, potato, pasture, tomato, 
Page 12 of 111

bell pepper, and hay, Tier 2 aquatic plant toxicity studies and for the TIPA salt only, and a 

freshwater fish early life stage study. The requested Tier 2 terrestrial plant toxicity studies on 

sensitive crops reported in incident reports were not submitted.

For aquatic animals, the RED determined that the endangered species LOC was exceeded for 

freshwater fish when the potassium salt was applied without incorporation and for 

estuarine/marine invertebrates when the TIPA salt was applied aerially (Table 4). For terrestrial 

animals, the mammalian listed species LOC was exceeded for both the TIPA and potassium salts 

regardless of application method. The listed and non-listed terrestrial plant LOCs were 

exceeded for all application types and a.i.’s. The maximum EEC determined in the assessment 

was approximately 800 ppb for a ground application of picloram TIPA salt applied at 2.2 lbs 

ai/A without incorporation and with a shallow (6 inch deep) receiving body.

Table 4. Exceedances of the LOC from Picloram RED

Species Risk

Listed Non-listed

Freshwater Fish1 Yes3 No

Freshwater Invertebrates No No

Estuarine/marine Fish1 Yes3 No

Estuarine/marine Inverts Yes4 No

Aquatic Plants (vascular & nonvascular) No No

Mammals Yes No

Birds2 No No

Terrestrial Invertebrates No No

Terrestrial Plants Yes Yes 1

Fish are considered surrogates for aquatic-phase amphibians 2

Birds are considered surrogates for reptiles and terrestrial-phase amphibians 3

Levels of concern were exceeded for endangered fish species for the potassium salt administered by ground 

application without incorporation only.

4

Levels of concern were exceeded for endangered estuarine/marine invertebrates only for the TIPA salt applied 

aerially.

4.2. Drinking Water Exposure Assessments

Characterization of drinking water exposure from surface water was addressed in the 1995 RED:

“Picloram has high potential to contaminate surface water by runoff from use areas. 

Regardless of the original chemical form, substantial quantities of the anion will be 

available for runoff for several months following application, considering its persistence 

in the environment. As indicated leaching will be the major route of dissipation from soil. 

Picloram that leaches into ground water may contaminate surface water in places where 

ground water discharges into surface water.”

Characterization of drinking water exposure from groundwater was also addressed in the 1995 

RED:

“Considering the widespread use of picloram and the detections in many states, the 

Agency is concerned about degradation of water quality in picloram use areas. Despite a 
Page 13 of 111

specialized use pattern, eventual contamination of ground water is virtually certain in 

areas where residues persist in the overlying soil. Once in ground water, the chemical is 

unlikely to degrade even over a period of several years.”

A drinking water assessment will be needed for registration review that addresses picloram acid 

and the impurity, HCB. 

4.3. Clean Water Act Programs

Picloram is not 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 picloram. Aquatic benchmarks have been established for picloram 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

Picloram acid and its salts, triisopropanolamine picloram (TIPA-salt) and potassium picloram 

(K-salt), are highly mobile and persistent in the environment in the form of the single chemical 

moiety, picloram. Picloram is prone to runoff and leaching with numerous monitoring detections 

in surface water and groundwater. The TIPA-salt and K-salt dissociate readily to picloram acid 

and the acid is present in its anionic form at environmental pH (pKa = 2.3).

Table 5. Chemical Structures Relevant to this Assessment

TIPA-salt of picloram

K-salt of picloram
Page 14 of 111

Picloram acid

Picloram is highly hydrophilic and non-volatile with aqueous solubility of 430 ppm, Henry’s law 

constant of 3.0x10-12 atm-m3/mol, and a log octanol-to-water partitioning coefficient of -1.92. 

Picloram acid is highly mobile with an estimated organic carbon adsorption coefficient of 7.2 

L/kgo.c. and highly persistent to metabolism with aerobic soil metabolism half lives ranging from 

167 days to 513 days in seven soils based on single first order kinetics. Current NAFTA 

degradation kinetics procedures will be used to estimate half-lives and subsequent input 

parameters in the registration review risk assessment. Picloram is stable to other forms of 

metabolism and hydrolysis. The only significant form of degradation for picloram is aqueous 

photolysis with a half-life of 16 days at pH 5. Major metabolites from aqueous photolysis 

include oxamic acid and 3-oxo-beta-alanine. Though not analyzed in terrestrial field dissipation 

studies, these degradates are not thought to persist in the environment as dissipation half-lives of 

the parent are significantly longer than the aqueous photolysis half-life of the parent (i.e., the 

aqueous photolysis pathway is not significant in the environment). Terrestrial field dissipation 

half-lives average 140 days on bare ground and 211 days on grass with picloram consistently 

leaching to the deepest sampled horizons in each study (36 to 60 inches). 

Chemicals in the pyridine carboxylic acid family such as picloram have been associated with 

incidents involving exposure and effects from compost and manure with undegraded residues. 

Due to the prevalence of use of picloram on materials commonly used for compost and animal

feed and the highly persistent nature of the compound, compost and manure represent complete 

exposure pathways to terrestrial plants. Chemicals in this family, including picloram, have also 

been associated with incidents involving exposure and effects from irrigation water with 

undegraded residues (see Section 6.3). Due to the highly persistent nature of the compound in 

water, irrigation water using contaminated surface or ground water also represents a complete 

exposure pathway to terrestrial plants.

Table 6. Chemical Properties and Environmental Fate Parameters of Picloram Acid

Parameter Value Description Source

Selected Physical/Chemical Parameters

Molecular mass (molecular 

formula)

241.5 g/mol 

432.6 g/mol

280.6 g/mol

Picloram acid

TIPA

K-salt

Picloram RED

Log dissociation constant (pKa) 2.3 Strong acid; Anionic 

form at environmental 

pH

Footprint1: 

Accessed 9/26/13
Page 15 of 111

Parameter Value Description Source

Vapor pressure (25°C) 6.3*10-7 torr Non-volatile MRID 45645503

Aqueous solubility (25°C) 430 ppm

218 ppm

Picloram acid

TIPA salt

Moderately soluble

Picloram RED

MRID 45787203

Henry’s Law Constant (25°C) 3.0x10-12 atm-m3/mol Non-volatile Footprint1

: 

Accessed 9/16/13

Log octanol-to-water partition 

coefficient

(log KOW)

-1.92 Hydrophilic Footprint1

: 

Accessed 9/16/13

Persistence

Hydrolysis half-life (20°C) Stable Footprint1: 

Accessed 9/16/13

Aqueous photolysis half-life 16 day UV-filtered Xenon arc 

lamp used, 25°C, pH 5

MRID 46027501

Aerobic soil metabolism halflife (25°C)383 days (loamy sand)

513 days (sandy loam)

171 days (silt loam)

167 days (loam)

429 days (loam)

412 days (clay)

190 days (silt loam)

Single first order 

estimates

Input parameter = 402 

days (USEPA, 2002a)

MRID 128976

Anaerobic soil metabolism halflife (25°C)Stable MRID128976

Anaerobic aquatic metabolism 

half-life (25°C)

Stable MRID128976

Mobility

Freundlich soil-water partition 

coefficients (KF); organic 

carbon-normalized Freundlich 

coefficients (KFOC)

0.14 L/kg;

7.2 L/kgOC

Highly Mobile Footprint1

: 

Accessed 9/16/13

Field Dissipation
Page 16 of 111

Parameter Value Description Source

Terrestrial field dissipation halflife; field coverCalifornia

278 days; bareground

135 days; grass plot

---

North Carolina

108 days; bareground

104 days; grass plot

---

Montana

256 days ± 37 days from 

4 tests; grass and 

herbaceous groundcover

---

Texas

34 days; bareground

MRID 42579002

---

MRID 42579001

---

MRID 42535302

MRID 42558302

---

MRID 40059801

Forest dissipation half-life Washington

123 days; bareground

34 days; unexposed soil

MRID 42579003

1 - http://sitem.herts.ac.uk/aeru/footprint/index2.htm

An aerobic aquatic metabolism study has not been submitted but it is not expected to impact

risk conclusions in the registration review risk assessment given current aquatic toxicity data.

PRZM/EXAMs was run assuming an aerobic aquatic metabolism of 100 days, 429 days, and 

stability (Table 7). The use scenario assumed was 1.9 kg a.i./ha with 1 application.

Table 7. EECs Demonstrating Impact of Aerobic Aquatic Metabolism Data

Aerobic Aquatic Metabolism 1 in 10 year peak, 21-day and 60-day 

EEC range in μg/L

Stable with KOC of 13 49-51

Stable with KOC of 0 52-55

429 days KOC of 13 12-15

100 days KOC of 13 3-7

The low toxicity endpoints and LOCs to consider for water are acute 96-hr LC50 of 5.5 mg/L for 

fish (5500 μg/L x LOC 0.05 = 275 μg/L), 2.61 mg/L for plants (2610 μg/L x LOC 1 = 2610

μg/L), and a NOAEC for fish of 0.55mg/L (550 μg/L LOC=1). These results indicate that 

whether aerobic aquatic metabolism is considered stable or within the range that might be 

observed based on aerobic soil metabolism data, the risk assessment will not be affected given 

current data. The submission of more sensitive aquatic toxicity data may introduce an endpoint 

that would be impacted by aerobic aquatic metabolism data. However, the new data would need 

to be at least 5x more sensitive than any currently available data in order for risk conclusions to 

be impacted by aerobic aquatic metabolism data.
Page 17 of 111

6. Receptors

Tables 8 through 13 provide a summary of the aquatic and terrestrial taxonomic groups, 

and the most sensitive surrogate species tested to characterize the potential acute and 

chronic ecological effects of picloram and its associated salts. In addition, the tables 

provide a preliminary overview of the potential acute toxicity of picloram and its 

associated salts by providing the acute toxicity classifications. Toxicity endpoint values 

for the TIPA and K salts have been converted to picloram acid equivalents to facilitate 

comparison between the different forms and these values will be used in the risk 

assessment. Based on the available ecotoxicity information, picloram and its associated 

salts are slightly to moderately acutely toxic to estuarine/marine and freshwater fish and 

slightly toxic to practically non-toxic to freshwater and estuarine/marine invertebrates.

For aquatic plants, the TIPA salt appears to be more toxic to vascular plants than to nonvascular plants, but for the potassium salt, the most sensitive aquatic plant taxa were 

freshwater diatoms. For terrestrial animals, the available data indicate that picloram and 

its associated salts are practically non-toxic to all taxa. As expected for an herbicide, 

picloram’s end-use products appear particularly toxic to terrestrial plants. Additional 

detail is included in the following tables. No information is available on the toxicity of 

the major metabolites oxamic acid and 3-oxo-beta-alanine. However, as described above 

in Section 5, these degradates are not expected to persist in the environment. 

6.1. Effects to Aquatic Organisms

Table 8. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for Picloram acid 

(PC Code 005101)

Taxonomic 

Group

Study 

Type

TGAI/

TEP

%ai

Surrogate Species

Toxicity Value

(95% Confidence 

Interval)

Acute Toxicity 

Classification Source

Freshwater fish1

Acute TGAI

92.9%

Rainbow trout

Oncorhynchus mykiss

96-hr LC50 = 5.5 mg 

ae/L (5.2—5.8)

Nominal

Moderately 

toxic

MRID 

00112016

Chronic 

(Early 

LifeStage)

TGAI

93.8%

Rainbow trout

Oncorhynchus mykiss

60-D NOAEC =

0.55 mg a.i./L

LOAEC = 0.88 mg 

ae./L

Endpoint:

Length & Weight

N/A MRID

00151784

Freshwater 

invertebrates Acute TGAI

90%

Water Flea 

(Daphnia magna)

48-hr EC50 = 34.4 

mg ae/L

(31.0—37.8) 

Nominal

Slightly toxic

MRID 

00141979
Page 18 of 111

Taxonomic 

Group

Study 

Type

TGAI/

TEP

%ai

Surrogate Species

Toxicity Value

(95% Confidence 

Interval)

Acute Toxicity 

Classification Source

Chronic TGAI

90%

Water Flea 

(Daphnia magna)

21-D NOAEC = 11.8 

mg ae/L

LOAEC = 18.1 mg 

ae/L

Endpoint: Mean 

brood size/adult & 

total young/adult

Mean-Measured

N/A

MRID 

00151783

Estuarine/marine 

fish

Acute -- No Data No Data N/A --

Chronic -- No Data No Data N/A --

Estuarine/marine 

invertebrates

Acute -- No Data No Data N/A --

Chronic -- No Data No Data N/A --

Acute -- No Data No Data N/A --

Aquatic plants 

and algae

Vascular -- No Data No Data N/A --

NonvascularTGAI

93.4%

Green Algae

Pseudokirchneriella 

subcapitata

96-Hr EC50 = 34.9 

mg ae/L (33.1—

36.9)

NOAEC = 18 mg 

ae/L

Nominal

N/A MRID 

00155937

1 Freshwater fish are surrogates for aquatic-phase amphibians.

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

TIPA salt (PC Code 005102)

Taxonomic 

Group

Study 

Type

TGAI/TE

P

%

Picloram 

ai

Surrogate Species

Toxicity Value

(95% Confidence 

Interval)

Acute 

Toxicity 

Classificati

on

Source

Freshwater fish1

Acute -- No Data No Data N/A --

Chronic 

(Early 

LifeStage)

TEP

5.9% ae

Fathead minnow

Pimephales promelas

32-D NOAEC = 4.02 mg 

ae/L

LOAEC = 6.65 mg ae/L

Mean-measured

Endpoint: Survival

N/A MRID

43959504
Page 19 of 111

Taxonomic 

Group

Study 

Type

TGAI/TE

P

%

Picloram 

ai

Surrogate Species

Toxicity Value

(95% Confidence 

Interval)

Acute 

Toxicity 

Classificati

on

Source

Freshwater 

invertebrates

Acute -- No Data No Data N/A --

Chronic -- No Data No Data N/A --

Estuarine/marine 

fish

Acute TEP

5.4% ae

Inland silverside

Menidia beryllina

96-hr LC50 = 31.6 mg 

ae/L

(19.89—33.07)

Slightly 

toxic

MRID 

43959503

Chronic -- No Data 60-D NOAEC = 3.16 mg 

ae/L N/A ACR2

Estuarine/marine 

invertebrates

Acute TEP

10.3%

Eastern oyster

Crassostrea virgninica

5.59 < 48-hr EC50 < 

10.06 mg ae/L

Nominal

Moderately

toxic

MRID

00129074

Acute TEP

10.3%

Pink shrimp

Penaeus duorarum 96-hr EC50 = 171mg ae/L Practically non-toxic

MRID

00129074

Chronic -- Eastern Oyster

Crassostrea virgninica

21-D NOAEC = 1.90 mg 

ae/L N/A ACR3

Aquatic plants 

and algae

NonvascularTEP

10.2%

Green Algae

Pseudokirchneriella 

subcapitata

120-Hr EC50 = 130 mg 

ae/L (100—170.4)

120-Hr NOAEC = 10.3 

mg ae/L 

Mean-measured

N/A MRID

41407701

NonvascularTEP

10.2%

Freshwater diatom

Navicula pelliculosa

120-Hr EC50 = 223 mg 

ae/L (179—279)

NOAEC = 145 mg ae/L

N/A MRID 

43230303

NonvascularTEP

5.4% ae

Blue-green algae

Anabaena flos-aquae

120-Hr EC50 = 352 mg 

ae/L (315—404) 

NOAEC = 31mg ae/L

N/A MRID 

43230309

Vascular TEP

5.4% ae

Duckweed

Lemna gibba

14-D EC50 = 2.61 mg ae/L

(1.45—4.70)

NOAEC = 0.13 mg ae/L

N/A MRID

43230312

1 Freshwater fish are considered a surrogate for aquatic-phase amphibians 2 For estuarine/marine fish, an ACR of 10 was derived from the picloram acid acute and chronic freshwater fish data 

and applied to the acute picloram TIPA salt estuarine/marine fish endpoint to generate a chronic NOAEC value. 3 For estuarine/marine invertebrates, an ACR of 2.92 was derived from the picloram acid acute and chronic daphnid 

data and applied to the lower bound of the picloram TIPA salt eastern oyster acute endpoint to generate a chronic 

NOAEC value.
Page 20 of 111

Table 10. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for Picloram K 

salt (PC Code 005104)

Taxonomic 

Group

Study 

Type

TGAI/

TEP

%ai

Surrogate Species

Toxicity Value

(95% Confidence 

Interval)

Acute 

Toxicity 

Classifica

tion

Source

Freshwater fish1

Acute TEP

24.4%

Rainbow Trout 

Oncorhynchus mykiss

96-Hr LC50 = 22.4 mg ae/L

Nominal

Slightly 

Toxic

MRID 

00129072

Chronic 

(Early 

LifeStage)

-- No Data No Data N/A --

Freshwater 

invertebrates

Acute TGAI

88.6%

Water flea

Daphnia magna 48-hr EC50 > 86 mg ae/L Practically 

non-toxic

MRID 

00129077

Chronic -- No Data No Data N/A --

Estuarine/marine 

fish

Acute

TEP

24.1%

(20.8% ae)

Sheepshead minnow 

Cyprinodon variegates

96-hr LC50 > 113 mg ae/L

Mean-measured

Practically 

non-toxic

MRID 

43959502

Chronic -- No Data 60-D NOAEC > 11.3 ppm N/A ACR2

Estuarine/marine 

invertebrates

Acute TEP

24.9%

Eastern oyster

Crassostrea virgninica

15 < 48-hr EC50 < 28 mg 

ae/L

Nominal

Slightly 

toxic

MRID

00129073

Acute TEP

24.9

Pink shrimp

Penaeus duorarum

96-hr EC50 = 108 mg ae/L

(98—119)

Practically 

non-toxic

MRID

00129073

Chronic -- Eastern oyster

Crassostrea virgninica

21-D NOAEC = 5.3 mg 

ae/L N/A ACR3

Aquatic plants 

and algae

NonvascularTEP

35.2%

Green Algae

Pseudokirchneriella 

subcapitata

120-Hr EC50 = 56 mg ae/L

(41—77)

120-Hr NOAEC = 11.3

mg ae/L

Mean-measured

N/A MRID

41407702

Nonvascular

TEP

27.9%

(24.1% ae)

Freshwater diatom

Navicula pelliculosa

120-Hr EC50 = 3.2 mg 

ae/L (2.7—3.7)

120-Hr NOAEC < 0.84

mg ae/L

Mean-measured

N/A MRID 

43230302

Nonvascular

TEP

27.9%

(24.1% ae)

Blue-green algae

Anabaena flos-aquae

120-Hr EC50 = 504 mg 

ae/L (462—558) 

120-Hr NOAEC = 336 mg 

ae/L

Mean-measured

N/A MRID 

43230308
Page 21 of 111

Taxonomic 

Group

Study 

Type

TGAI/

TEP

%ai

Surrogate Species

Toxicity Value

(95% Confidence 

Interval)

Acute 

Toxicity 

Classifica

tion

Source

Vascular

TEP

27.9% 

(24.1% ae)

Duckweed

Lemna gibba

14-D EC50 = 82.3 mg ae/L

(65--107)

14-D NOAEC = 43.5 mg 

ae/L

Measured (0-hr)

N/A MRID

43230311

1 Freshwater fish are considered surrogates for aquatic-phase amphibians. 2 For estuarine/marine fish, an ACR of 10.0 was derived from the picloram acid acute and chronic freshwater fish data 

and applied to the picloram potassium salt estuarine/marine nondefinitive acute endpoint to generate a chronic NOAEC 

value. 

3 For estuarine/marine invertebrates, an ACR of 2.92 was derived from the picloram acid acute and chronic daphnid 

data and applied to the lower bound of the picloram potassium salt eastern oyster acute endpoint to generate a chronic 

NOAEC value.

Based on the above toxicity data, the acid and potassium salt have similar acute toxicity 

to freshwater fish while picloram acid is approximately an order of magnitude more toxic 

to freshwater fish on a chronic basis than the TIPA salt. A study with coho salmon 

(MRID 45205107) using the potassium salt had a slightly more sensitive LC50 of 15.1 mg 

ae/L compared to the rainbow trout study, but was considered qualitatively supplemental 

since the exposure was only for 24 hours. No acute freshwater fish data is available for 

the TIPA salt and no chronic freshwater fish data is available for the potassium salt. The 

two salts have a similar low acute toxicity to estuarine/marine fish. The lack of chronic 

saltwater fish data for the acid or either salt is considered a data gap, however an ACR 

from picloram acid’s acute and chronic rainbow trout endpoints can be applied to the 

saltwater acute fish data for both salts and results in NOAECs that are higher than the 

maximum EECs predicted from the RED. Additionally, the acute data indicate that 

freshwater fish are more sensitive than saltwater fish. Therefore, the weight of evidence 

indicates it is unlikely that additional data would add significant value to the risk 

assessment.

Picloram acid and the potassium salt both exhibited low acute toxicity to freshwater 

invertebrates, with no data available for the TIPA salt. The only chronic data available 

for picloram’s effects to freshwater invertebrates is for the acid which showed a reduction 

in reproduction (mean brood size/adult and total young/adult) at 18.1 mg ae/L. Although 

no data was available for picloram acid’s effects to estuarine/marine invertebrates, the 

TIPA and potassium salts had similar acute toxicity to both the eastern oyster and pink 

shrimp. In the absence of additional data, an ACR from picloram acid’s acute and 

chronic daphnid endpoints will be applied to the lower bound of the most sensitive acute 

estuarine/marine invertebrate endpoints to derive a chronic endpoint for estuarine/marine 

invertebrates for both the TIPA and potassium salts. This approach yields NOAECs that 

are higher than the maximum EECs predicted from the RED. Therefore, it is unlikely 

that additional data would add significant value to the risk assessment. 

For aquatic plants, green algae was more sensitive to picloram acid compared to the two 

salts. Vascular plants were approximately two orders of magnitude more sensitive than 
Page 22 of 111

non-vascular plants to the TIPA salt while for the potassium salt the freshwater diatom 

was 1-2 orders of magnitude more sensitive than other aquatic plant taxa. Data are 

missing for effects of either the acid or salts to marine diatoms. This is considered a 

major data gap for the TIPA salt, since the freshwater diatom was much more sensitive 

than the other aquatic plant taxa to this salt, but data are not required for either the acid or 

the potassium salt.

6.2. Effects to Terrestrial Organisms

Table 11. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Picloram 

acid (PC Code 005101)

Taxonomic 

Group

Study Type TGAI/TEP

%ai

Surrogate 

Species

Toxicity Value

(all units in 

terms of 

measured 

active 

ingredient)

Acute 

Toxicity 

Classifica

tion

Source 

Birds1

Acute 93.8%

Mallard Duck 

(Anas 

platyrhynchos)

LD50 > 2510 

mg/kg-bw

Practically 

non-toxic

MRID 

00157173

Acute oral -- No Data No Data N/A --

Sub-acute 

dietary -- No Data No Data N/A --

Chronic -- No Data No Data N/A --

Mammals

Acute Oral TGAI

94.1%

Laboratory rat 

(Rattus 

norvegicus)

LD50 = 4,012 

mg/kg (females)

Practically 

non-toxic

MRID

40479413

Acute 

Inhalation

TGAI

94.1%

Laboratory rat 

(Rattus 

norvegicus)

4-Hr LC50 > 

0.035 mg/L I MRID 

40479415

Subchronic 

Feeding

TGAI 

92%

Laboratory rat 

(Rattus 

norvegicus)

13-Wk

NOEL: 50 

mg/kg/d

LOEL: 150 

mg/kg/day

Endpoints: liver 

weight increases 

and changes in 

the liver

N/A MRID 

00110537
Page 23 of 111

Taxonomic 

Group

Study Type TGAI/TEP

%ai

Surrogate 

Species

Toxicity Value

(all units in 

terms of 

measured 

active 

ingredient)

Acute 

Toxicity 

Classifica

tion

Source 

Chronic (2-

Generation 

Reproduction)

TGAI

94.1%

Laboratory rat 

(Rattus 

norvegicus)

NOAEL = 200 

mg/kg/day

LOAEL = 1000 

mg/kg/day

Endpoints: 

lesions in 

kidneys, blood 

in urine, 

decreased urine 

specific gravity, 

increased 

kidney weights

N/A MRID 

40834301

Terrestrial 

Invertebrates Acute contact

TEP

% ai 

unknown

Honey bee 

(Apis mellifera 

L.)

48-hr LD50 > 

14.5 μg/bee

Practically 

non-toxic

MRID 

00036935

Terrestrial 

plants2

Seedling 

Emergence

-- Monocot – No 

Data No Data N/A --

-- Dicot – No 

Data No Data N/A --

Vegetative 

Vigor

-- Monocot – No 

Data No Data N/A --

-- Dicot – tomato No Data N/A --

1 Birds are considered a surrogate for terrestrial phase amphibians and reptiles

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

TIPA salt (PC Code 005102)

Taxonomic 

Group

Study 

Type

TGAI/TEP

%Picloram 

ai

Surrogate 

Species

Toxicity 

Value

(all units in 

terms of 

measured 

active 

ingredient)

Acute 

Toxicity 

Classification

Source 

Birds1

Acute oral -- No Data No Data N/A --

Acute oral -- No Data No Data N/A --
Page 24 of 111

Taxonomic 

Group

Study 

Type

TGAI/TEP

%Picloram 

ai

Surrogate 

Species

Toxicity 

Value

(all units in 

terms of 

measured 

active 

ingredient)

Acute 

Toxicity 

Classification

Source 

Sub-acute 

dietary

TEP

10.2%

Mallard duck

(Anas 

platyrhynchos)

& Bobwhite 

quail (Colinus 

virginianus)

8-D LC50 > 

5600 mg

ae/kg/d

Practically 

non-toxic

MRIDs

00129069

00129071

Chronic -- No Data No Data N/A --

Mammals

Acute Oral TEP

33.9% ae

Laboratory rat 

(Rattus 

norvegicus)

14-D LD50 > 

2,800 mg

ae/kg

Practically 

non-toxic

MRID 

41381201

Acute 

Inhalation

TEP

33.9% ae

Laboratory rat 

(Rattus 

norvegicus)

4-Hr LC50 > 

0.04 mg ae/L II MRID 

41381203

Subchronic 

Feeding

TEP

34% ae

Laboratory rat 

(Rattus 

norvegicus)

13- Wk 

NOAEL = 50

mg ae/kg/d

LOAEL = 300

mg ae/kg/day

Endpoints: 

increased liver 

weights, 

hepatocellular 

hypertrophy 

and increased 

kidney 

weights in 

males only

N/A MRID 

41442701

Terrestrial 

Invertebrates

Acute 

contact

TEP

5.68% ae

Honey bee 

(Apis mellifera 

L.)

48-hr LD50 > 

56 μg ae/bee

Practically 

non-toxic 41366901

Terrestrial 

plants2

Seedling 

Emergence

-- Monocot – No 

Data No Data N/A --

-- Dicot – No 

Data No Data N/A --

Vegetative 

Vigor

-- Monocot – No 

Data No Data N/A --

-- Dicot – tomato No Data N/A --

1 Birds are considered a surrogate for terrestrial phase amphibians and reptiles
Page 25 of 111

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

K salt (PC Code 005104)

Taxonomic 

Group

Study 

Type

TGAI/TEP

%ai

Surrogate 

Species

Toxicity 

Value

(all units in 

terms of 

measured 

active 

ingredient)

Acute 

Toxicity 

Classification

Source 

Birds1

Acute oral -- No Data No Data N/A --

Acute oral -- No Data No Data N/A --

Sub-acute 

dietary

TEP

24.4% ae

11.6% ae

Mallard duck

(Anas 

platyrhynchos)

& Bobwhite 

quail (Colinus 

virginianus)

8-D LC50 > 

8,600 mg

ae/kg

Practically 

non-toxic

MRIDs

00129068

00112978

Chronic -- No Data No Data N/A --

Mammals

Acute Oral TEP

38.8%

Laboratory rat 

(Rattus 

norvegicus)

14-D LD50 = 

3048 mg

ae/kg 

(females)

Practically 

non-toxic 40479401

Acute 

Inhalation

TEP

38.8%

Laboratory rat 

(Rattus 

norvegicus)

4-Hr LC50 > 

1.41 mg ae/L -- 40479403

Terrestrial 

Invertebrates

Acute 

contact

TEP

30.4% ae

Honey bee 

(Apis mellifera 

L.)

48-hr LD50 > 

86 μg ae/bee

Practically 

non-toxic 41366902

Terrestrial 

plants2

Seedling 

Emergence

TEP

24.1%

Monocot –

Wheat

Triticum 

aestivum

EC25 = 0.082 

lbs ae/A 

(0.053—

0.13)

NOAEC = 

0.027 lbs 

ae/A

N/A MRID 

43959505

TEP

24.1%

Dicot –

Tomato

(Solanum 

lycopersicum)

EC25 = 

0.0066 lbs 

ae/A 

(0.0047—

0.095)

NOAEC = 

0.0034 lbs 

ae/A

N/A MRID

43959505
Page 26 of 111

Taxonomic 

Group

Study 

Type

TGAI/TEP

%ai

Surrogate 

Species

Toxicity 

Value

(all units in 

terms of 

measured 

active 

ingredient)

Acute 

Toxicity 

Classification

Source 

Vegetative

Vigor

TEP 

25.2%

Monocot –

Wheat

(Triticum 

sestivum)

EC25 = 0.028

lbs ae/A

EC05 = 

0.0035 lbs 

ae/A

N/A MRID 

44156701

TEP 

25.2%

Dicot –

Tomato

(Solanum 

lycopersicum)

EC25 = 

0.00016 lbs 

ae/A

NOAEC = 

0.000026 lbs 

ae/A

N/A MRID 

44156701

1 Birds are considered a surrogate for terrestrial phase amphibians and reptiles.

Picloram acid is considered practically non-toxic to birds on an acute oral basis. Though 

no acute oral data is available for the salts, both salts are practically non-toxic on an acute 

dietary basis. There is no data for the effects of picloram acid or its salts to passerine 

birds. Passerine bird species can frequently be more sensitive than upland and waterfowl 

bird species. Since sublethal effects including loss of coordination, lower limb weakness 

and lethargy occurred at the lowest treatment level (398 mg a.i./kg) in the acute oral 

study (MRID 00157173) with picloram acid and treatment related mortalities occurred in 

the bobwhite dietary study (MRID 00129068) with the potassium salt, the lack of a 

subacute oral passerine study is considered a major data gap. No acceptable chronic data 

for birds was available for picloram acid or either salt. This is also considered a major 

data gap. 

 

Picloram acid and both salts are considered practically non-toxic to mammals on an acute 

oral basis. Acute inhalation studies with the rat resulted in non-definitive (>) endpoints 

for the acid and both salts. On a subchronic basis, picloram acid had similar toxicity to 

rats as the TIPA salt. On a chronic basis, exposure to picloram acid resulted in increased 

incidence of microscopic lesions in male (and some female) kidneys, blood in urine, 

decreased urine specific gravity, and increased absolute & relative kidney weights at 

1000 mg a.i./kg.

Picloram acid and both salts were also practically non-toxic on an acute contact basis to 

the honey bee. 

Quantitatively acceptable data on the effects of picloram to terrestrial plants was only 

available for the potassium salt. Although a previous seedling emergence and vegetative 

vigor study was considered supplemental and had been used to support the registration of 

the TIPA salt (MRID 41296501), this study does not provide quantitatively acceptable 

data since a NOAEC could not be achieved for several species, height data was not 

collected and only three replicates were used which prohibits the accurate extrapolation 
Page 27 of 111

of an EC05. The study may only be utilized qualitatively to characterize risk. The lack of 

quantitatively acceptable terrestrial plant data with the TIPA salt is a major data gap.

A number of end-use products contain picloram in combination with another herbicide 

(i.e. 2,4-D, dicamba, fluroxypyr and/or triclopyr). Since these products are labeled for 

aerial application, there exists the potential for spray drift to non-target plants. Therefore, 

these data are needed to conduct a risk assessment:

• Terrestrial plant vegetative vigor (850.4150) and seedling emergence 

(850.4100) tests using the most sensitive dicot and monocot species: 

tomato, drybean, soybean, onion and wheat using TEP.

For the preceding studies where we are requesting data on TEP, data are needed on a 

representative product that contains both picloram and the additional ai(s). When 

there are multiple products with dual active ingredients, as is the case for the picloram 

and 2,4-D a.i.’s, the representative TEP used is normally the product with the highest 

percentages of active ingredient and/or is expected to result in the highest toxicity. 

EFED conducted an analysis comparing the toxicity of formulations containing either 

picloram K salt or 2,4-D TIPA salt with multi-ai data from formulations containing both 

picloram TIPA salt and 2,4-D TIPA salt in order to see if the combination of multiple 

herbicides had enhanced toxicity (Appendix B). For taxa where data was available on 

these three formulations (including aquatic plants, aquatic invertebrates and fish), there 

was no evidence of enhanced toxicity from the picloram and 2,4-D TIPA salts mixture. 

However, no data was available for the effect of formulations solely containing one 

active ingredient of2,4-D TIPA salt on terrestrial plants. In this case, EFED used 2,4-D 

DMA salt as a comparison, which was identified as the most toxic 2,4-D salt to dicots in 

the 2013 2,4-D Problem Formulation (USEPA, 2013). The most sensitive terrestrial 

plant species for which data was available for both picloram salts and 2,4-D DMA salt 

was the tomato. Since no quantitatively acceptable information was available for the 

picloram TIPA salt formulation (co-formulated with 2,4-D TIPA salt), the analysis was 

conducted using a qualitatively acceptable study (MRID 41296501). The tomato was an 

order of magnitude more sensitive to the picloram/2-4 D TIPA salts formulation than to

the picloram K salt formulation and 4 orders of magnitude more sensitive than to the 

2,4-D DMA salt formulation. This indicates that there is potential for additive or 

synergistic effects from formulations containing picloram and an additional herbicide.

6.3. Ecological Incidents

A review on August 28, 2013 of the Ecological Incident Information System (EIIS, 

version 2.1.1), which is maintained by the Agency’s Office of Pesticide Programs, 

indicates a total of 56 reported ecological incidents in the United States associated with 

the use of the picloram acid and salt active ingredients (summarized by certainty in Table 

14 with a more thorough listing by date and location in Appendix C). 51 of the reported 

incidents associated with picloram involved damage to terrestrial plants and appear to be 

crop damage. At least 10 of these terrestrial plant incidents were due to exposure of 
Page 28 of 111

nontarget plants from spray drift. Five of the reported incidents associated with picloram 

involved fish kills. The certainty categories1 regarding the likelihood that the use of 

picloram caused the 56 incidents ranged from Unlikely (1 incident, 2%), Possible (26

incidents, 46%), Probable (26 incidents, 46%) and Highly Probable (3 incidents, 5%). 

At least 42 of the reported incidents (75.0%) have occurred since the time of the RED 

(1995). 11 (20%) of the incident reports did not have information regarding the date of 

occurrence, therefore it is unclear in those cases whether they occurred before the time of 

the RED or are more recent. Three reported incidents may have involved the use of 

irrigation water and an additional three more were reported showing residues in compost 

as the potential cause of the incident. A more thorough discussion of the aquatic 

incidents, irrigation water incidents and composting incidents is provided below.

Table 14. Summary of ecological incidents associated with picloram use, by certainty

Incident 

Type Use Type

Certainty

All 

(excluding 

unlikely)

Unlikely Possible Probable Highly 

Probable

Aquatic (Misuse) 2 2

(Registered Use) 2 1 1

(Unknown) 1 1

Plants Agricultural Site 

(Misuse) 11 6 4 1

Agricultural Site 

(Registered Use) 28 1 10 17

Agricultural Site 

(Unknown) 12 7 4 1

Total 56 1 26 26 3

Aquatic Incidents

In 1989, in Montana (I000046-001), thousands of trout at a fish hatchery were killed after 

Tordon (containing picloram potassium salt) was sprayed by a road crew 1⁄4 mile 

upstream from the hatchery, followed by heavy rain. Residues of picloram in vegetation 

near the road found 0.12 ppm picloram. The certainty of injury being attributed to the 

fish in this incident as a result of picloram use was categorized as probable and the 

legality was considered a registered use of picloram. 

 1 The Ecological Incident Information System (EIIS) used by EPA to store incident data relies on the following 

certainty indices: 

• Highly Probable: (residues detected in affected organisms and other lines of evidence support cause)

• Probable: (residues were not measured or the measured residues were not sufficient to be considered toxic, 

but pesticide was used in close proximity and would be capable of exerting such an effect)

• Possible: multiple pesticides were used in close proximity and any of them are capable of causing such an 

effect.

• Unlikely: there are no measured residues and the observed effects are not consistent with those caused by 

pesticides used in the area or there was no pesticide use known in the area.

• Unrelated: effects observed in the incident are unrelated to pesticide use.
Page 29 of 111

In 1994 (Incident I001616-001; location not reported), trees were treated with Access 

Herbicide (containing picloram) near a pond. One fish (species not reported) was found 

dead in the pond. No residue information was provided, but the incident was considered 

of high probability and the legality was considered a registered use.

Incident I003325-001 (location and date not reported) was a report indicating that Tordon 

22K (containing picloram potassium salt) was used as a surface/spot treatment with a 

roadside sprayer and two days later there was a fish kill in an adjacent pond consisting of 

two dead brown trout and 103 dead rainbow trout. The certainty that picloram caused 

this incident was considered possible and the legality of the use was considered an 

accidental misuse.

In 1997, in Oklahoma (I006139-001), it was reported that there was a fish kill of an 

unknown number of four fish species (bass, catfish, crappie and perch) after an 

application of a pesticide containing picloram and 2,4-D and following run-off from a 

heavy rain into a half acre pond. The grass around the pond was also affected and 

reported to be dying. The certainty that picloram caused this incident was considered 

possible and the legality was not determined. 

In 1998, in Texas (I007873-001), 300 fish were reported to have died three to four weeks 

after Tordon had been sprayed on weeds near a pond and following a heavy rain. The 

species of fish was not reported. The certainty that picloram caused this incident was 

considered possible and the legality of the use was considered an accidental misuse. 

As several of these incidents do not describe the timing between pesticide application and 

resulting fish kill, it is possible that some of these incidents were a result of plant damage 

leading to decay and subsequent lower dissolved oxygen concentrations in water, though 

this may be unlikely for Incident I003325-001, where fish died so shortly (2 days) after 

pesticide application.

Irrigation Water Incidents

Incident I001458-001 (location and date not reported) was a report indicating that Tordon 

22K (containing picloram potassium salt) was applied on weeds near a well. The well 

water was subsequently used to irrigate 90 acres of potatoes, which were injured. The 

certainty of injury being attributed to the non-target plants in this incident as a result of 

picloram use was categorized as probable and the legality of the use was not determined. 

In 1998, in Virginia (I008451-001) tobacco plants were reportedly injured after irrigation 

from a pond. The landowner reported that an application of picloram to a transmission 

right-of-way had been made in 1974 and caused a large degree of non-target plant injury 

and death (primarily tuliptrees). The landowner built a pond in the drainage leading from 

the right-of-way in 1984. When he irrigated his tobacco from that pond, the tobacco was 

stunted or killed. In 1998, the landowner irrigated from a pond uphill from the original 

pond which had tested clear at the time of the 1984 planting. However, this pond was 

pumped low and towards the end of the season the landowner’s tobacco plants were 
Page 30 of 111

injured following application of irrigation water. Residues in the pond and spring water 

showed picloram to be present in concentrations from 1—3.71 ppb. The certainty of 

injury being attributed to the non-target plants in this incident as a result of picloram use 

was categorized as probable and the original use was considered a registered use of 

picloram. 

Incident I004352-001 was reported in Oklahoma (date of incident not reported) where 

Tordon 101 was applied to a railroad right-of-way, but accidentally to a section where 

picloram entered a water source used to irrigate five acres of greenhouses growing a 

variety of potted plants including 50,000 poinsettas which were all damaged. Samples of 

the water used for irrigation indicated picloram in concentrations from 3—28 ppb. The 

certainty of injury being attributed to the non-target plants as a result of picloram use was 

categorized as highly probable. The legality of the use was considered an accidental 

misuse. 

Composting Incidents

In 2000, in Washington (I010624-001), home gardeners reported non-target plant injuries 

associated with the distribution of compost by Washington State University. Tordon 101 

Mixture containing picloram TIPA salt and 2,4-D was used on University fields and the 

resulting harvested hay was fed to cattle. Manure from the cattle contained picloram 

residues and residues were also detected in soil samples from home gardens where the 

compost was applied. It was considered unlikely that damage to the non-target plants 

could be attributed to the 2,4-D use, but the certainty of injury being attributed to the nontarget plants as a result of picloram use was considered probable. The legality of the use 

was considered a registered use. 

In 2007, in Texas (I018930-031), an incident was reported where Grazon (picloram TIPA 

salt and 2,4-D) allegedly caused injury to 2 acres of cantelope, watermelon, onion, 

tomatoes and peppers to the point where these crops could not produce fruits. Manure 

from horses fed hay previously treated with Grazon was composted and used for fertilizer 

in an organic production system. The manure was composted, applied to the field and 

incorporated with tillage equipment. The incident report cites that label directions were

not followed in this case. However, there was apparently no way for the organic grower 

to know that Grazon had been used on the hay that was fed to the horses prior to the 

grower obtaining manure and composting. The certainty of injury being attributed to the 

non-target plants as a result of picloram use was considered possible. The legality of the 

use was considered an accidental misuse. 

In 2007, in Virginia (I018677-001), an incident was reported where mulch containing 

picloram residues was applied to a field and resulted in damage to 10 acres of crops 

(tomato, potato and squash). Plant samples showed detections of the herbicide. The 

certainty of injury being attributed to the non-target plants as a result of picloram use was 

considered highly probable. The legality of the use was not determined. 
Page 31 of 111

7. Exposure Pathways of Concern

The environmental fate properties and use patterns of picloram indicate that direct spray

onto food residues, spray drift, leaching to ground water, and runoff represent potential 

transport mechanisms of picloram to aquatic and terrestrial organisms. Due to picloram’s 

persistence, picloram may be transported in the environment in compost (either from 

composted vegetation or manure). Finally, picloram may be present in surface water or 

groundwater used as irrigation water. 

Drinking water and inhalation exposure pathways were screened using the SIP 

(Screening Imbibition Program) and STIR (Screening Tool for Inhalation Risk) screening 

methods. Drinking water was found to be a potential exposure pathway of concern (LOC 

exccedances are expected) on an acute basis for birds, but not mammals. SIP and STIR 

are described in detail at: http://www.epa.gov/oppefed1/models/terrestrial/index.htm.

The Screening Tool for Inhalation Risk (STIR v.1.0) was used to assess the potential for 

risk to birds and mammals through inhalation exposure. The exposure pathways that are 

assessed by this tool include both droplet inhalation and vapor-phase inhalation. STIR, 

used in the problem formulation phase, is intended to determine if exposure is likely and 

not whether the potential for risk exists. If STIR predicts that exposure is likely, 

additional inhalation data may be necessary to adequately assess risk due to the inhalation 

exposure pathway. Based on STIR analysis, inhalation is not considered likely to be a 

significant route of exposure for birds and mammals (see Appendix D for STIR inputs 

and outputs). It should be noted that the mammalian inhalation LC50sfor picloram acid 

and both salts were all non-definitive (>) values. 

The Screening Imbibition Program (SIP 1.0, Released June 15, 2010) was used to 

calculate an upper bound estimate of exposure using picloram’s solubility in water (430 

mg/L), the most sensitive acute and chronic avian toxicity endpoints (mallard acute LD50 

of 2510, no chronic NOAEC available) and the most sensitive acute and chronic 

mammalian toxicity endpoints (female Laboratory Rat acute LD50 of 3536 for picloram 

potassium salt and Rat chronic NOAEL of 200 mg/kg-bw). Drinking water exposure 

alone was not determined to be a potential pathway of concern for mammalian species on 

either an acute or chronic basis. Although drinking water exposure alone does not appear 

to be of concern, this does not take into account that when aggregated with other 

exposure pathways (dietary food sources, dermal, inhalation) drinking water may 

contribute to a total exposure that has a potential for effects on non-target animals and 

should be explored further. Because there is a high degree of conservatism in the SIP 1.0 

exposure estimate, there is limited expectation that use scenarios not triggering a SIP 1.0 

concern would contribute significantly to aggregate risks from water plus diet when a 

refined water exposure model is incorporated in the actual quantitative risk assessment. 

Detailed information about SIP v1.0, as well as the tool, can be found on the EPA’s 

website at http:www.epa.gov/pesticides/science/models_pg.htm#terrestrial.
Page 32 of 111

However, drinking water exposure alone was determined to be a potential pathway of 

concern for avian species on an acute basis and data was insufficient to evaluate whether 

drinking water exposure is a potential pathway of concern for avian species on a chronic 

basis. This pathway will be explored further with the development of SIP v.2.0 in the 

Ecological Risk Assessment for Picloram. The chronic avian data expected to be 

requested in the DCI will also be used in this assessment of drinking water exposure. For 

a sample of the output generated by SIP v.1.0, please see Appendix D. 

Consistent with what has been noted in the RED, residues of picloram in surface or 

ground water and their use for irrigation could result in potential injury to nontarget 

plants because of the compound's persistence. Analysis of the incident data supports the 

possibility that irrigation water is a viable exposure pathway. This pathway will be 

explored further in the Ecological Risk Assessment for Picloram by calculating the 

amount of irrigated water needed to exceed the available terrestrial plant endpoints on an 

acre of land using the expected environmental concentrations in surface and ground 

water. 

Analysis of the incident data also support the possibility that compost, whether through 

application of composted plant materials containing picloram residues or manure from 

horses or cows fed such plant material, may also be a viable exposure pathway and could 

result in potential injury to nontarget plants because of the compound’s persistence.

Exposure to aquatic organisms is likely to occur, and may affect both fish and 

invertebrates. Exposure may occur via ingestion or uptake through the gills and/or 

integument. Aquatic plants are also expected to be exposed via direct contact or vascular 

uptake.

8. Analysis Plan

8.1. Stressors of Concern

8.1.1. Ecological Risk Assessment

Due to the persistence of picloram, the stressor of concern is the parent compound only as 

acid equivalents across the three picloram moieties. Although no data is available for the 

environmental degradation of the two salts to picloram acid, it is expected that they will 

readily be converted to picloram acid.

8.1.2. Drinking Water 

The drinking water assessments conducted to support the registration review human 

health risk assessments of picloram will address the parent compound only as acid 

equivalents across the three picloram moieties in surface and ground waters. Picloram is 

likely to be found in groundwater and surface water due to its persistence and high 

mobility. The formulation impurity, HCB, will be assessed separately in a screening 

level approach.
Page 33 of 111

8.2. Measures of Exposure 

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. 

Available Monitoring Data

There are 39 detections of picloram in groundwater in 19 states ranging from 0.2 ppb to 

3.9 ppb (NAWQA). The peak groundwater detection was in Shelby County, Tennesse. 

STORET reports 195 detections in surface water in 11 states ranging from 0.1 ppb to 24 

ppb with 5 detections between 10 ppb and 20 ppb. The peak detection was in Doniphan 

County, Kansas. NAWQA reports additional surface water monitoring data with 87 

detections in 26 states ranging from 0.1 ppb to 2.7 ppb.

Aquatic Exposure Modeling

The models used to predict aquatic estimated environmental concentrations (EECs) are 

the Pesticide Root Zone Model coupled with the Exposure Analysis Modeling System 

(PRZM/EXAMS) and PRZM-Groundwater (PRZM-GW) publically available at: 

http://www.epa.gov/oppefed1/models/water/index.htm. The PRZM/EXAMS Standard 

Pond scenario will be used to estimate the aquatic EECs in surface water. Modeling will 

be conducted across the three picloram moieties in equal terms using the acid equivalent 

approach. All use patterns will be assessed using standard approaches, however, 

applications to rooftops is a non-standard use. Applications to rooftops will be assessed 

with the same method as spot treatments. That is, it is assumed residues are washed off 

by a minimum of 2 mm of water for washoff stipulated in the PRZM model. The treated 

area will be assumed to be 50% and impervious surface scenarios will be used.

Terrestrial Exposure Modeling

Chemicals in the pyridine carboxylic acid family such as picloram have been associated 

with incidents involving exposure and effects from compost with undegraded residues. 

EFED does not currently model pesticide concentrations in compost as guideline

metabolism data do not address the conditions in compost. EFED will investigate this 

issue in the ecological risk assessment.

Exposure estimates for terrestrial animals assumed to be in the target area or in an area 

exposed to spray drift are derived using the T-REX model (version 1.5.2, March 2012). 

This model incorporates the Kenaga nomograph, as modified by Fletcher et al. (1994), 

which is based on a large set of field residue data. The upper limit values from the 

nomograph represent the 95th percentile of residue values from actual field measurements 

(Hoerger and Kenega 1972). The Fletcher et al. (1994) modifications to the Kenaga 

nomograph are based on measured field residues from 249 published research papers, 
Page 34 of 111

including information on 118 species of plants, 121 pesticides, and 17 chemical classes. 

A default 35-day foliar dissipation rate will be used because no foliar dissipation data 

have been submitted. Screening level calculations have suggested that the drinking water 

exposure pathway may be a significant concern for birds and will be further evaluated at 

the time of risk assessment with SIP v2.0. 

EECs for terrestrial plants inhabiting dry and wetland areas are derived using TerrPlant 

(version 1.2.2, December 2006). This model uses estimates of pesticides in runoff and in 

spray drift to calculate EECs. EECs are based upon solubility, application rate and 

minimum incorporation depth in addition to type of formulation and method of 

application.The Agency is currently developing a replacement model for TerrPlant. If the 

replacement has been approved prior to the initiation of the risk assessment, this new 

model will be used instead. 

Two spray drift models, AgDisp and AgDRIFT, are used to assess exposures of aquatic 

and terrestrial organisms to picloram deposited in terrestrial and aquatic habitats by spray 

drift. AgDrift (version 2.1.1; dated 12/29/2011) is the model most commonly used to 

simulate spray drift into terrestrial and aquatic environments from aerial and ground 

applications. AgDisp (version 8.13; dated 12/14/2004) (Teske and Curbishley, 2003) is 

used when a parameter needs to be modeled that is not available in AgDRIFT. Spray 

drift analysis will be an important part of the analysis in defining the potential area of 

effects for endangered species.

EFED does not currently have a standardized methodology for determining risk to nontarget plants from applications of irrigation water sourced from surface or ground water 

that has been contaminated by a pesticide. However, EFED anticipates that an irrigation 

water analysis will be conducted at the time of the risk assessment using exposure values 

generated from currently available aquatic exposure models such as PRZM/EXAMS for 

surface water or PRZM-GW for groundwater exposures. This approach will be used to

determine a depth (in inches) of irrigation water on a one-acre field necessary to cause an 

LOC exceedance to terrestrial plants and compared with representative cultural practices 

to characterize the potential risk associated with this exposure scenario.

These models are parameterized using relevant reviewed environmental fate data from 

registrant submissions and the literature; model input values will be consistent with the 

most recent version of EFED’s aquatic model input parameter guidance (Version 2.1; 

EFED 2009). 

Applications Directly to Trees

Applications to individual trees can result in absorption and translocation of aminopyralid 

from the site of application throughout the tree. Birds, mammals, and terrestrial 

invertebrates may be exposed through ingestion of leaves, seeds, pollen, or other edible 

portions of the tree. Leaves containing aminopyralid may fall onto the ground or into 

water resulting in movement of aminopyralid to soil and water. Finally, trees treated with 

aminopyralid may be used as compost. There is no currently approved model for 
Page 35 of 111

estimating potential exposure to organisms from tree injection, cut-stump treatment, hack 

and squirt method, and frill and girdle methods. A screening-level estimate of exposure 

will be completed for this assessment. The method used to estimate exposure is 

discussed in a recently completed assessment in EFED, and the screen is based on the 

following assumptions (Bosecker and White, 2010, D383620; Hurley and Spatz, 2010, 

D381025): 

(1) Aquatic Risk Assessment

a. The total mass of chemical applied to the trees on one acre is assumed to 

enter a 20,000,000 L water body directly; EEC = total mass of chemical 

applied to trees on one acre/ 20,000,000 L.

b. The maximum application rate is assumed to be 0.11 lbs a.e./A/year; EEC 

= those estimated in GENEEC for broadcast uses.

(2) Concentration of chemical in leaves

a. Leaf concentration was estimated by assuming that 100% of the chemical 

was translocated to the leaves. Leaf mass is estimated using allometric 

equations developed for blue oak trees presented by the USDA Forest 

Service (Karlick and McKay, 2002). EEC = total mass of chemical 

applied / leaf mass on tree.

8.3. Measures of Effect 

Toxicity data presented in Section 6 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, 2009), 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.

9. 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 registered uses of pesticides in registration review. The process for 

evaluating potential risks to listed species is further described at 

http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm. An endangered species 

assessment has not been conducted for picloram to date.
Page 36 of 111

10. Endocrine Disruptor Screening Program

As required by FIFRA and the Federal Food, Drug, and Cosmetic Act (FFDCA), EPA

reviews numerous studies to assess potential adverse outcomes from exposure to

chemicals. Collectively, these studies include acute, subchronic and chronic toxicity,

including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, 

and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ

histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy

rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments,

EPA evaluates acute tests and chronic studies that assess growth, developmental and

reproductive effects in different taxonomic groups. As part of the Preliminary Problem

Formulation for Registration Review (DP Barcode 416059), EPA reviewed these data

and selected the most sensitive endpoints for relevant risk assessment scenarios from the

existing hazard database. However, as required by FFDCA section 408(p), picloram is

subject to the endocrine screening part of the Endocrine Disruptor Screening Program

(EDSP).

EPA has developed the 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 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. Under FFDCA 

section 408(p), the Agency must screen all pesticide chemicals. 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. On 

June 14, 2013, EPA published the Revised Second List of Chemicals for Tier I Screening 

in a Federal Register Notice. This revised second list included test orders/data call-ins 

for an additional 109 chemicals, which contained 41 pesticide active ingredients. 

Picloram is among the group of 41 pesticide active ingredients on the revised second list 

of chemicals to be screened under the EDSP. The Agency will review the EDSP Tier 1 

data and any “other scientifically relevant information” submitted in response to test 

orders. Based on this review the Agency will determine the need for additional testing. 

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

list of 67 chemicals or the overview of the second list of 109 chemicals, the test 
Page 37 of 111

guidelines and the Tier 1 screening battery, please visit our website: 

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

11. Preliminary Identification of Data Gaps 

11.1. Environmental Fate

Table 15 through Table 17 identify environmental fate 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 risk assessment.

Table 15. Submitted Environmental Fate Data for Picloram Acid (PC code 005101)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Comments, Justification and 

Assumptions EPA will Make in 

Absence of Data 

835.2120 Hydrolysis --- --- No Other aquatic studies indicate that 

picloram is stable to hydrolysis

835.2240 Aqueous

photolysis

46027501 Supplemental No

835.2410 Soil photolysis 157175 Supplemental No

835.4100 Aerobic Soil 

Metabolism

128976 Acceptable No

835.4200 Anaerobic soil 

metabolism

128976 Acceptable No

835.4300 Aerobic 

aquatic 

metabolism

--- --- No Persistence is demonstrated in aerobic 

soil metabolism and terrestrial field 

dissipation studies. If the registrant 

considers aerobic aquatic metabolism to 

be a significant route of metabolism, a 

study demonstrating such would be 

welcomed. However, a preliminary 

analysis was performed on page 16 of 

this document indicating that a study 

would likely not impact risk conclusions

835.4400 Anaerobic 

aquatic 

metabolism

--- --- No Persistence is demonstrated in aerobic 

soil metabolism and terrestrial field 

dissipation studies. If the registrant 

considers anaerobic aquatic metabolism 

to be a significant route of metabolism, 

a study demonstrating such would be 

welcomed.
Page 38 of 111

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Comments, Justification and 

Assumptions EPA will Make in 

Absence of Data 

835.1230

835.1240

Adsorption/ 

desorption and 

leaching

111422 Supplemental Yes MRID 111422 did not have sufficient 

number of acceptable soils and 

radiochemical purity was not reported in 

MRD 141646. Accurate quantification 

of sorption coefficients is highly 

important for a compound with high 

expected mobility. Current reported 

estimates are derived from Footprint1.

141646 Supplemental

835.6100 Terrestrial 

field 

dissipation

42579001 Acceptable No

42579002 Acceptable

42535302

42558302

Acceptable

835.6300 Forest field 

dissipation

41395301 Acceptable No

42579003 Acceptable

850.1730 Fish BCF 42121108 Acceptable

850.6100 Water and Soil

Environmental 

Chemistry 

Methods

45366

69078

--- Yes Pending review, the data gap remains 

for methods on soil and water

Compost 

Environmental 

Chemistry 

Methods

--- --- Yes Methods that can be used with 

equipment found in state labs and use 

standards that can be readily obtained 

are requested.

850.6100 Soil 

Independent 

Laboratory 

Validation

--- --- Yes

Water 

Independent 

Laboratory 

Validation

--- --- Yes

Compost

Independent 

Laboratory 

Validation

--- --- Yes

NonGuidelineDissipation of 

Residues in 

Compost

Study

-- -- Yes The study will be used to characterize 

the risk from picloram residues in 

compost and may demonstrate potential 

mitigations such as compost holding 

times. It is requested that a study 

protocol is submitted for review before 

the study is conducted. In the absence 

of data, EPA will assume that picloram 

does not degrade in compost.

1 - http://sitem.herts.ac.uk/aeru/footprint/index2.htm
Page 39 of 111

Table 16. Submitted Environmental Fate Data for TIPA-salt of Picloram (PC code 005102)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data

835.6100 Terrestrial 

field 

dissipation

00160126

40059801

Supplemental No

Table 17. Submitted Environmental Fate Data for K-salt of Picloram (PC code 005104)

OCSPP 

Guideline

Data 

Requirement

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data

835.6100 Forest field 

dissipation

140317 Supplemental No

835.7100 Prospective 

Groundwater

42535302 Supplemental Yes Less than 1/500th of an inch of 

irrigation water would be 

required to reach the vegetative 

vigor tomato NOAEC of 0.00016 

lb a.e./ac based on Tier I PRZMGW EECs. Furthermore, less 

than one inch of irrigation water 

would be required to reach 9 out 

of 10 reported terrestrial plant 

endpoints. A prospective 

groundwater study performed in 

an area representative of typical 

picloram use conditions would

allow for better characterization 

of expected groundwater 

concentrations. Without a 

prospective groundwater study, 

only PRZM-GW can be relied 

upon to assess the exposure route.

11.2. Effects

Table 218 and Table 3 19 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 risk assessment. Table 20 identifies the ecological 

effects studies requested for TEPs containing multiple active ingredients formulated with 

picloram.
Page 40 of 111

Table 2. Submitted Aquatic Ecological Effects Data for Picloram

OCSPP

Guideline Data Requirement PC Code

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct 

risk 

assessment?

Current Additional 

Data Need

850.1010 Freshwater 

invertebrate 

acute toxicity

005101 00141979 Acceptable No --

005102 None N/A No

005104 00129077 Supplemental No

850.1025

850.1035

850.1045

850.1055

Saltwater invertebrate 

acute toxicity 

005101 None N/A

005102 00129074 Supplemental No

005102 00129074 Supplemental No

005104 00129073 Supplemental No

005104 00129073 Supplemental No

850.1075 Freshwater fish acute 

toxicity 

005101 00112016 Acceptable No --

005102 No Data N/A

005104 45205107 Supplemental--

Qualitative

005104 00129072 Supplemental

850.1075 Saltwater fish acute 

toxicity 

005101 No Data N/A No --

005102 43959503 Acceptable No

005104 43959502 Acceptable No

850.1300 Freshwater 

invertebrate 

life cycle 

005101 00151783 Acceptable No --

005102 No Data N/A No

005104 No Data N/A No

850.1350 Saltwater 

invertebrates 

life cycle 

005101 None N/A No In the absence of data 

EPA will use an acute to 

chronic ratio (ACR) to 

estimate a chronic 

endpoint for the saltwater 

invertebrate. 

005102 None N/A No

005104 None N/A No

850.1400 Freshwater fish 

early-life stage

005101 00151784 Acceptable No --

005102 43959504 Acceptable No

005104 No Data N/A No

850.1400 Saltwater fish 

early-life stage 

005101 No Data N/A No In the absence of data 

EPA will use an acute to 

chronic ratio (ACR) to 

estimate a chronic 

endpoint for the saltwater 

invertebrate.

005102 No Data N/A No

005104 No Data N/A No

850.1500 Fish life cycle 005101 No Data N/A No --

005102 No Data N/A No

005104 No Data N/A No

850.4400 Aquatic plant 005101 No Data N/A No --
Page 41 of 111

OCSPP

Guideline Data Requirement PC Code

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct 

risk 

assessment?

Current Additional 

Data Need

Toxicity Test using 

Lemna spp.

005102 43230312 Acceptable No

005104 43230311 Acceptable No

850.4500 Algal toxicity 005101 00155937 Supplemental No No data is available for 

the estuarine/marine 

diatom for the TIPA or 

potassium salts. Since the 

freshwater diatom was the 

most sensitive taxa tested

for the TIPA salt, a study 

on estuarine/marine 

diatoms is required. A 

new study is not required 

for the potassium salt

005102 41407701 Acceptable No

005102 43230303 Acceptable No

005102 No Data N/A Yes

005104 41407702 Acceptable No

005104 43230302 Acceptable No

005104 No Data N/A No

850.4550 Cyanobacteria 005102 43230309 Acceptable No --

005104 43230308 Acceptable No

Table 3. Submitted Terrestrial Ecological Effects Data for Picloram

OCSPP 

Guideline

Data 

Requirement

PC 

Code Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed for 

risk 

assessment?

Current Additional Data 

Need

850.2100 Avian oral 

toxicity

005101 00157173 Acceptable Yes A passerine acute oral 

study is required due to 

sublethal effects in the 

acute oral study and 

treatment related 

mortalities in the dietary 

studies with the potassium 

salt. 

005102 No Data N/A No

005104 No Data N/A Yes

850.2200 Avian dietary 

toxicity 

005101 No Data N/A No --

005102 00129069 Supplemental No

005102 00129071 Supplemental No

005104 00129068 Supplemental No

005104 00112978 Supplemental No

850.2300 Avian 

reproduction

005101 None N/A Yes An acceptable avian 

reproduction study using 

the bobwhite quail with 

either picloram acid or the 

potassium salt is required. 

005102 None N/A Yes

005104 None N/A Yes

850.3020 Honey bee 

acute contact 

toxicity

005101 00036935 Supplemental No --

005102 41366901 Acceptable No

005104 41366902 Acceptable No
Page 42 of 111

OCSPP 

Guideline

Data 

Requirement

PC 

Code Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed for 

risk 

assessment?

Current Additional Data 

Need

850.3030 Honey bee

residue on 

foliage

005101 No Data N/A No --

005102 No Data N/A No

005104 No Data N/A No

850.3040 Field testing 

for 

pollinators

005101 No Data N/A No --

005102 No Data N/A No

005104 No Data N/A No

850.4100 Seedling 

Emergence 

and Seedling 

Growth

005101 No Data N/A No New Tier 2 data using the 

TIPA salt on tomato, 

drybean, soybean, onion 

and wheat is required. (see 

the Executive Summary)

005102 41296501 Supplemental—

Qualitative

Yes

005104 43959505 Acceptable No

850.4150 Vegetative 

Vigor

005101 No Data N/A No New Tier 2 data using the 

TIPA salt on tomato, 

drybean, soybean, onion 

and wheat is required. (see 

the Executive Summary)

005102 41296501 Supplemental—

Qualitative

Yes

005104 44156701 Acceptable No

Table 20: Summary of Additional Data Requirements for Representative Technical End Use 

Products Containing Multiple Active Ingredients

OCSPP 

Guideline Data Requirement

850.4150 Terrestrial Plant Vegetative Vigor using Tomato, Drybean, Soybean, Onion and Wheat

850.4100 Terrestrial Plant Seedling Emergence using Tomato, Drybean, Soybean, Onion and 

Wheat

Guideline Number: 835.7100

Study Titles: Prospective Groundwater Study

Rationale for Requiring the Data

Five separate incidents have been reported on crop damage due to picloram contaminated 

drinking water. The veracity of these incidents is confirmed by comparing a screening level 

groundwater concentration of 0.421 mg a.e./L to the most sensitive terrestrial plant endpoint 

(vegetative vigor tomato NOAEC = 0.00016 lb a.e./ac) . Less than 1/500th of an inch of 

irrigation water would be required to reach this endpoint. Furthermore, less than one inch of 

irrigation water would be required to reach 9 out of 10 reported terrestrial plant endpoints. A 

prospective groundwater study performed in an area representative of typical picloram use 

conditions would allow for better characterization of expected groundwater concentrations.

Practical Utility of the Data

How will the data be used? The data will be used to advise on necessary depth to groundwater, 

well setback distances and/or other limitations on the use of groundwater for irrigation in 

picloram use areas in conjunction groundwater modeling estimates from PRZM-GW. 

How could the data impact the Agency’s future decision-making? The data will be used as the 
Page 43 of 111

most substantial piece in a weight-of-evidence approach to characterize the vulnerability of 

groundwater to picloram contamination and to develop mitigation options for the protection of 

irrigation water.

Guideline Number: N/A

Study Titles: Dissipation study in compost

Rationale for Requiring the Data

The application of picloram to vegetative matter that is subsequently used as compost or animal 

feed has been found to retain picloram residues and affect non-target plants. This route of 

exposure is common across the picolinc acid herbicides (aminopyralid, clopyralid, and 

picloram). A study is requested to demonstrate the rates of degradation and leaching in 

vegetative and manure composts. 

Practical Utility of the Data

How will the data be used? Through the SFIREG Pesticides Operations & Management 

committee on September 16, 2013, it was made known that Dow AgroSciences is developing a 

molecular imprinted polymer for solid phase extraction that could be used for detecting picloram 

in compost. It was expected that a method could be released to state laboratories by April 2014. 

A compost dissipation study would be instrumental in interpreting the monitoring data that will 

become available after this method is disseminated. 

How could the data impact the Agency’s future decision-making? The study will be used to 

characterize this risk from picloram residues in compost and may demonstrate potential 

mitigations such as compost holding times.

12. References 

Bosecker, E., & White, K. 2010.D383620. Ecological Risk Assessment for the Proposed 

Section 24C New Use of Triisopropanolamine Salt of Aminopyralid for Control 

of Herbaceous Broadleaf Weeds and Woody Plants in Forests, Non-cropland, 

Grazed areas, and Industrial Non-crop Areas in Arkansas. D383620. December 7, 

2010. Environmental Fate and Effects Division. Office of Pesticide Programs. 

Office of Chemical Safety and Pollution Prevention. United States 

Environmental Protection Agency. 

Fletcher, J.S., J.E. Nellesson and T. G. Pfleeger. 1994. Literature review and evaluation 

of the EPA food-chain (Kenaga) nomogram, an instrument for estimating 

pesticide residues on plants. Environ. Tox. And Chem. 13(9):1383-1391.

Hoerger, F. and E.E. Kenaga. 1972. Pesticide residues on plants: correlation of 

representative data as a basis for estimation of their magnitude in the 

environment. IN: F. Coulston and F. Corte, eds., Environmental Quality and 
Page 44 of 111

Safety: Chemistry, Toxicology and Technology. Vol 1. George Theime

Publishers, Stuttgart, Germany. pp. 9-28.

Hurley, P., & Spatz, D. 2010.D381025. Section 3 Product Registration Request for 

Expansion of Tree Species for Emamectin Benzoate Tree Injection Use to Control 

Arthropod Pests. D381025. October 5, 2010. Environmental Fate and Effects 

Division. Office of Pesticide Programs. Office of Chemical Safety and Pollution 

Prevention. United States Environmental Protection Agency. 

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.

Teske, M.E. and T.B. Curbishley. 2003. AGDISP Version 8.07 User Manual. Continum 

Dynamics, Inc. Ewing, NJ 08618. Prepared for USDA Forest Service, 

Morgantown, WV.

Tomlin, C. 2004. Picloram entry in the E-Pesticide Manual, Thirteenth Edition, Crop 

Protection Publications, British Crop Protection Council. Available at: 

http://www.bcpcbookshop.co.uk.

Tu, M., C. Hurd, J.M. Randall. 2001. Weed Control Methods Handbook: Tools and 

Techniques for Use in Natural Areas. Nature Conservancy. Available at 

http://www.invasive.org/gist/handbook.html

USEPA, 1995. Reregistration Eligibility Decision (RED) Picloram. Office of Pesticide 

Programs. Prevention, Pesticides and Toxic Substances. U.S. Environmental 

Protection Agency, Washington D.C.

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. 2002a. Guidance for Selecting Input Parameters in Modeling the Environmental 

Fate and Transport of Pesticides, Version II (February 28, 2002). Office of 

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

Environmental Protection Agency. Arlington, VA.
Page 45 of 111

U.S. EPA. 2002b. Pesticide Root Zone Model (PRZM) Field and Orchard Crop 

Scenarios: Standard Procedures for Conducting Quality Control and Quality 

Assurance. Office of Pesticide Programs, Environmental Fate and Effects 

Division, U.S. Environmental Protection Agency. 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.

USEPA. 2009a. ECOTOXicology Database, United States Environmental Protection 

Agency (USEPA). Available at http://cfpub.epa.gov/ecotox/

USEPA, 2013. BEAD Chemical Profile (BCP) for Registration Review: Picloram Salts 

and Esters Case (005101, 005102, and 005104). Biological and Economic 

Analysis Division. Office of Pesticide Programs. U.S. Environmental Protection 

Agency. Arlington, VA. July 18, 2013.

Appendix A- OPPIN Bibliography

005101 Picloram Eco Effects Bibliography

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference

41144 Stevenson, G.T.; Lapham, K. (1967) A Gamebird Toxicology Study of 4-Amino-3,5,6-

trichloropicolinic acid, Triethylamine salt and Isoctyl ester in Bobwhite Quail. 

(Unpublished study received on 

unknown date under 8F0660; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:094930-F) 

111457 Stevenson, G.; Lapham, K. (1967) A Gamebird Toxicology Study of ... ?Tordon|, 

Triethylamine Salt and Isooctyl Ester in Bobwite Quail. (Unpublished study received Jun 

28, 1979 under 0F0863; submitted by Dow Chemical Co., Indianapolis, IN; 

CDL:098349-H) 

157173 Beavers, J. (1983) An Acute Oral Toxicity Study in the Mallard with Picloram 

Technical: Final Report: Project No. 103-221. Unpub- lished study prepared by Wildlife 

International Ltd. 15 p. 

71-2 Avian Dietary Toxicity

MRID Citation Reference

41113 or 

75781 or 

Stevenson, G.T. (1965) A Gamebird Toxicology Study--Acute Dietary Feeding

of Tordon to Wild Type Mallard Ducklings. (Unpublished study received Nov 6, 1967 
Page 46 of 111

80912 

multiple 

submissi

on

under 0F0863; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094525-X) 

or ACC 91155 or ACC 91153

Stevenson, G.T. (1965) A Gamebird Toxicology Study--Acute Dietary Feeding of 

Tordon^(R)I to Wild Type Mallard Ducklings. (Unpub- lished study received Nov 21, 

1967 under 8F0660; submitted by Dow Chemical Co., Indianapolis, Ind.;

41471 Stevenson, G.T. (1965) A Game Bird Toxicology Study--Acute Dietary Feeding of 

Tordon^(R)I in Bobwhite Quail. (Unpublished study received Nov 6, 1967 under 

0F0863; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094524-D) 

41472 or 

75780

Stevenson, G.T. (1965) A Game Bird Toxicology Range Finding Study of Tordon in 

Wild Type Mallard Ducklings. (Unpublished study received Nov 6, 1967 under 

0F0863; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094524-E) or 

91155-G

41473 Stevenson, G.T. (1965) A Gamebird Toxicology Study--Acute Dietary Feeding of 

Tordon^(R)I to Wild Type Mallard Ducklings: Summary. (Unpublished study received 

Nov 6, 1967 under 0F0863; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:094524-F) 

95165 Stevenson, G.T. (1965) A Game Bird Toxicology Range Finding Study of Tordon, 

Daxtron and Dursban in Wild Type Mallard Ducklings: GH-A-107. (Unpublished 

study received Jun 10, 1969 under 9G0817; submitted by Dow Chemical Co., 

Indianapolis, Ind.; CDL:091411-N) 

111510 Kenaga, E. (1974) Letter sent to M. Adamczyk dated Aug 16, 1974 ?Weedone 2,4,5-

TP|. (Unpublished study received Oct 9, 1974 under 264-61; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:120636-A) 

22923 Hill, E.F.; Heath, R.G.; Spann, J.W.; et al. (1975) Lethal Dietary Toxicities of 

Environmental Pollutants to Birds: Special Scientific Report--Wildlife No. 191. (U.S. 

Dept. of the Interior, Fish and Wildlife Service, Patuxent Wildlife Research Center; 

unpublished report)

71-4 Avian Reproduction

MRID Citation Reference

41470 Stevenson, G.T. (1965) Multiple Generation Reproductive Study of Tordon Fed Japanese 

Quail. (Unpublished study received Nov 6, 1967 under 0F0863; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:094524-C) 

41909 Stevenson, G.T. (1965) A Summary of Japanese Quail Reproduction Studies with 

Tordon^RI. (Unpublished study received Nov 6, 1967 under 0F0863; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:094524-B) 

69974 Stevenson, G.T. (19??) A Reproduction Study of Tordon--Picolinic Acid: 4-Amino-3,5,6-

trichloro-, in Japanese Quail: Experiment No. 3-804-10. (Unpublished study received Nov 

1, 1964 under unknown admin. no.; submitted by Dow Chemical U.S.A., Midland, Mich.; 
Page 47 of 111

CDL:130992-K) 

4803300

5

Albers, P.; Hoffman, D. (1984) Evaluation of Potential Embryotoxicity and Teratogenicity 

of 42 Herbicides, Insecticides, and Petroleum Contaminants to Mallard Eggs. Archives of 

Environmental Contamination and Toxicology 13: 15-27.

141980 Somers, J.; Moran, E.; Reinhart, B. (1978) Reproductive success of hens and cockerels 

originating from eggs sprayed with 2,4-D, 2, 4-5-T and picloram followed by early 

performance of their proge- ny after a comparable in ovo exposure. Bull. Environm. 

Contam. Toxicol. 20:111-119. 

72-1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

68507 Hughes, J.S.; Davis, J.T. (1964?) Effects of Selected Herbicides on Bluegill Sunfish. 

(Louisiana, Wild Life and Fisheries Commis- sion; unpublished study; CDL:231131-

A) 

102855 Silvo, O. (1967) Alustavia Tutkimuksia Eraiden Herbisidien Myrkyllisyydesta 

Nuorille Karpin Poikasille (Cyprinus catpio L.). Helsinki, Fin.: ?s.n.|. (Suomen 

Kalatalous 32; also In unpublished submission received Feb 3, 1976 under 960-163; 

sub- mitted by Balcom Chemicals, Inc., Greeley, CO; CDL:228944-V) 

111458 Bond, C.; Wilson, D.; Malick, J. (1967) Progress Report on Aquatic Weed Research 

(Project 773). (Unpublished study received Jun 28, 1979 under 0F0863; prepared by 

Oregon State Univ., Agricul- tural Experiment Station, Dept. of Fisheries and 

Wildlife, sub- mitted by Dow Chemical Co., Indianapolis, IN; CDL:098349-I) 

112016 Batchelder, T. (1974) Acute Fish Toxicity of Picloram--(Dry Tordon Acid). 

(Unpublished study received Sep 10, 1976 under 464-541; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:226137-C) 

112971 Hughes, J.; Davis, J. (1963) Variations in toxicity to bluegill sunfish of phenoxy 

herbicides. Weeds 11(1):50-53. (Also In unpublished submission received Jun 28, 

1979 under 0F0863; sub- mitted by Dow Chemical Co., Indianapolis, IN; 

CDL:098349-O) 

129076 Mayes, M.; Dill, D. (1982) The Toxicity of Picloram ... to Repre- sentative Freshwater 

Organisms: ES-561. (Unpublished study re- ceived Jun 24, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-O) 

129078 McCarty, W.; Alexander, H.; Park, C. (1977) Comparative Toxicity of Three Samples 

of Technical Picloram Containing Various Amounts of N''-(3,4,5,6-Tetrachloro-2-

pyridinyl) Guanidine to Bluegill. (Unpublished study received Jun 24, 1983 under 

464-502; submit- ted by Dow Chemical U.S.A., Midland, MI; CDL:250605-Q) 

129080 Sergeant, M.; Blazek, D.; Elder, J.; et al. (1971) The toxicity of 2,4-D and picloram 

herbicides to fish. Proc. Indiana Academy of Science 80:114-123. (Also In 

unpublished submission received Jun 24, 1983 under 464-502; submitted by Dow 
Page 48 of 111

Chemical U.S.A., Midland, MI; CDL:250605-T) 

129086 Woodward, D. (1976) Toxicity of the herbicides dinoseb and picloram to cutthroat 

(Salmo clarki) and lake trout (Salvelinus namay- cush). Journal of the Fisheries 

Research Board of Canada 33(8): 1671-1676. (Also In unpublished submission 

received Jun 24, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, 

MI; CDL:250605-Z) 

151784 Mayes, M.; Dill. D.; Hopkins, D. (1984) The Toxicity of Technical Picloram to the 

Embryo, Larval, and Juvenile Stages of the Rainbow Trout (Salmo gairdneri 

Richardson): ES-703. Unpublished study prepared by Dow Chemical USA. 17 p. 

40098001 Mayer, F.; Ellersieck, M. (1986) Manual of Acute Toxicity: Inter- pretation and Data 

Base for 410 Chemicals and 66 Species of Freshwater Animals. US Fish & Wildlife 

Service, Resource Pub- lication 160. 579 p.

TN 23. TN 

24, TN 28 

and TN 48 

(MRID 

111461)

McCann, J.A. USEPA Beltsville Animal Biology tests with Bluegill sunfish- see Fed 

Lab Data

TN 32, TN 

33, TN 34

McCann, J.A. USEPA Beltsville Animal Biology tests with Rainbow trout and 24.9% 

ai product. - see Fed Lab Data

No MRID 

on DER Mayer, F.L. 1982. Fathead minnow acute toxicity study. 

40094602 Johnson, W.W. and M.T. Finley (1980) Handbook of Acute Toxicity of Chemicals to 

Fish and Aquatic Invertebrates (U.S. Department of the Interior Fish and Wildlife 

Service, Resource Publication 137, Unpublished Report).

No MRID Woodward, D.F. (1979) Assessing the Hazard of Picloram to Cutthroat Trout. J. 

Range manage. 32: 230-232.

No MRID Cope, O.B. (1966) Estimated LC50 Values for Several Pesticides and Bluegills, 

Testes at 65°F. Quarterly Progress Reports: Sports Fishery Research. U.S. Fish and 

Wildlife Service.

No MRID Cope, O.B. (1964) Toxicities of Herbicides to Goldfish, Rainbows, Bluegills and 

Largemouth Bass. Quarterly Progress Reports: Sports Fishery Research. U.S. Fish and 

Wildlife Service.

51597 McCann, J.A. (1974) Letter sent to Charles College dated Oct 22, 1974 ?Fish toxicity 

data|. (U.S. Environmental Protection Agen- cy, Animal Biology Laboratory, 

unpublished study; CDL:224700-T) 

72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference
Page 49 of 111

111510 -

repeated

Kenaga, E. (1974) Letter sent to M. Adamczyk dated Aug 16, 1974 ?Weedone 

2,4,5-TP|. (Unpublished study received Oct 9, 1974 under 264-61; submitted by 

Dow Chemical U.S.A., Midland, MI; CDL:120636-A) 

129076 -

repeated

Mayes, M.; Dill, D. (1982) The Toxicity of Picloram ... to Repre- sentative 

Freshwater Organisms: ES-561. (Unpublished study re- ceived Jun 24, 1983 under 

464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-O) 

141979 McCarty, W. (1977) Toxicity of 4-Amino-3,5,6-trichloropicolinic Acid, Picloram, 

to Daphnids: Final Report. Unpublished study prepared by Dow Chemical U.S.A. 8 

p. 

151783 Gersich, F.; Hopkins, D.; Milazzo, D. (1984) The Acute and Chronic Toxicity of 

Technical Picloram (4-Amino-3,5,6-trichloropicolinic acid) to Daphnia magna 

Straus: ES-690. Unpublished study pre- pared by Dow Chemical USA. 16 p. 

154234 Gersich, F.; Hopkins, D.; Milazzo, D. (1984) The Acute and Chronic Toxicity of 

Technical Picloram (4-Amino-3,5,6-trichloropicolinic Acid) to Daphnia magna 

Straus: ES-690. Unpublished study pre- pared by Dow Chemical USA. 3 p. 

45713401 Boeri, R.; Wyskiel, D.; Ward, T. (2002) Picloram Acid: Acute Toxicity to the 

Gammarid, Gammarus pseudolimnaeus: Lab Project Number: 2390-DO: 021027. 

Unpublished study prepared by T.R. Wilbury Laboratories, Inc. 28 p. {OPPTS 

850.1020} 

45765901 Boeri, R.; Wyskiel, D.; Ward, T. (2002) Picloram Acid: Acute Toxicity to the 

Ramshorn Snail, Planorbella trivolvis: Lab Project Number: 2389-DO: 021028. 

Unpublished study prepared by T.R. Wilbury Laboratories, Inc. 27 p. 

40098001 Mayer, F.; Ellersieck, M. (1986) Manual of Acute Toxicity: Inter- pretation and 

Data Base for 410 Chemicals and 66 Species of Freshwater Animals. US Fish & 

Wildlife Service, Resource Pub- lication 160. 579 p.

114875 

MRID

not on 

DER

Sanders, H.O. and O.B. Cope (1968) The Relative Toxicities of Several Pesticides 

to Naiads of Three Species of Stoneflies. Limnol. Oceanogr. 13:112-117.

40094602 Johnson, W.W. and M.T. Finley (1980) Handbook of Acute Toxicity of Chemicals 

to Fish and Aquatic Invertebrates (U.S. Department of the Interior Fish and Wildlife 

Service, Resource Publication 137, Unpublished Report).

72-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

45205107 Lorz, H.; Glenn, S.; Williams, R. et al. (1979) Effects of Selected Herbicides on 

Smolting of Coho Salmon: Lab Project Number: R-804283: EPA-600/3-79-071. 

Unpublished study prepared by Corvallis Environmental Research Laboratory. 103 p. 

No MRID Butler, P.A. (1964) The Effects of Pesticides on Fish and Wildlife. Commercial 
Page 50 of 111

Fishery Investigations. U.S. Fish and Wildlife Service.

Estuarine species- not reviewed

72-4 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study

MRID Citation Reference

41147 Duddles, G.A. (1968) The Acute Fish Toxicity of the Triisopropanol- amine salt of 4-

Amino-3,5,6-trichloropicolinic acid. (Unpub- lished study received on unknown date 

under 8F0660; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094930-I) 

41475 Alexander, H.C.; Batchelder, T.L. (1965) Results of a Study on the Acute Toxicity of 

Tordon^(R)I Herbicide to Three Species of Fish. (Unpublished study received Nov 6, 

1967 under 0F0863; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:094524-H) 

41481 Cope, O.B. (1964) Quarterly Progress Reports: Sport Fishery Re- search. ?: U.S. Fish 

and Wildlife Service. (Quarter ending Jun 30, 1964; pp. 48-50 only, published study; 

CDL:094524-N)

55714 Silvo, O.E.J. (1967) Alustavia Tutkimuksia Eraiden Herbisidien Myrkyllisyydesta 

Nuorille Karpin Poikasille (~Cyprinus carpio~ L~.). N.P. (Suomen Kalatalous 32 

Finlands Fiskerier; incom- plete; also~In~unpublished submission received Jul 11, 

1961 un- der 1E1046; submitted by U.S. Dept. of the Army, Washington, D.C.; 

CDL:093359-X) 

61946 Swedberg, D. (1972) Letter sent to George MacLean dated Sep 5, 1972 ?Toxicity 

static bioassays--Tordon and Ronnel--cutthroat trout|. (U.S. Fish and Wildlife Service, 

Fish-Pesticide Research Labora- tory, unpublished study; CDL:227666-D) 

129086 Woodward, D. (1976) Toxicity of the herbicides dinoseb and picloram to cutthroat 

(Salmo clarki) and lake trout (Salvelinus namay- cush). Journal of the Fisheries 

Research Board of Canada 33(8): 1671-1676. (Also In unpublished submission 

received Jun 24, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, 

MI; CDL:250605-Z) 

151784 Mayes, M.; Dill. D.; Hopkins, D. (1984) The Toxicity of Technical Picloram to the 

Embryo, Larval, and Juvenile Stages of the Rainbow Trout (Salmo gairdneri 

Richardson): ES-703. Unpublished study prepared by Dow Chemical USA. 17 p. 

45760301 Boeri, R.; Wyskiel, D.; Ward, T. (2002) Picloram Acid: Life Cycle Study in the 

Daphnid, Daphnia magna: Lab Project Number: 2391-DO: 021029. Unpublished 

study prepared by T.R. Wilbury Laboratories, Inc. 46 p. 

151783 Gersich, F.; Hopkins, D.; Milazzo, D. (1984) The Acute and Chronic Toxicity of 

Technical Picloram (4-Amino-3,5,6-trichloropicolinic acid) to Daphnia magna Straus: 

ES-690. Unpublished study pre- pared by Dow Chemical USA. 16 p. 
Page 51 of 111

72-7 Simulated or Actual Field Testing

MRID Citation Reference

129085 Woodward, D. (1979) Assessing the hazard of picloram to cutthroat trout. Journal of 

Range Management 32(3):230-232. (Also In un- published submission received Jun 

24, 1983 under 464-502; sub- mitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250605-Y) 

151783 Gersich, F.; Hopkins, D.; Milazzo, D. (1984) The Acute and Chronic Toxicity of 

Technical Picloram (4-Amino-3,5,6-trichloropicolinic acid) to Daphnia magna Straus: 

ES-690. Unpublished study pre- pared by Dow Chemical USA. 16 p. 

No MRID 

on DER Bidlack, H.D. 1980. Kinetics of Aged Picloram in a model microcosm

122-1 Seed Germination/Seedline Emergence and Vegetable Vigor

MRID Citation Reference

155937 Dow Chemical U.S.A. (1986) Nontarget Area Phytotoxicity [Using Technical 

Picloram]. Unpublished compilation. 109 p. 

40054501 Weseloh, J. (1987) A Summary of Three Greenhouse Trials to Deter- mine the Effects 

of Picloram, 4-Amino-3,5,6-Trichloropicolinic Acid on Seed Germination, Seedling 

Emergence, and upon Vegeta- tive Vigor of Six Dicotyledonae and Four 

Monocotyledonae Crop Cultivars. Unpublished study prepared by Dow Chemical 

U.S.A. 112 p. 

40579801 Weseloh, J. (1988) A Summary of Three Greenhouse Trials to Determine the Effects 

of Picloram, 4-Amino-3,5,6-Trichloro- picolinic Acid on Seed Germination, Seedling 

Emergence, and upon Vegetative Vigor when Applied at 560 G/HA, on Six 

Dicotyledoneae and Four Monocotyledoneae Crop Cultivars: Laboratory Project ID 

GH-P 1366. Unpublished study prepared by Midland Field Research Station, Dow 

Chemical U. S. A. 30 p. 

45194801 Schwab, D. (1998) The Effects of Picloram in Irrigation Water at 5 ppb and 20 ppb on 

Soybean Growth and Yield: Lab Project Number: 43894: RES97063. Unpublished 

study prepared by ABC Laboratories, Inc. 69 p. 

45289601 Wright, J. (2000) Phytotoxicity and Yield Effects on Soybeans Following a Soil 

Surface Application of Picloram K Salt: Lab Project Number: RES97047. 

Unpublished study prepared by Dow AgroSciences LLC. 94 p. 

122-2 Aquatic plant growth

MRID Citation Reference

155937 Dow Chemical U.S.A. (1986) Nontarget Area Phytotoxicity [Using Technical 
Page 52 of 111

Picloram]. Unpublished compilation. 109 p. 

Accession No. 

261128

Elder, J.H., C.A. Lembi and D.J. Moore (1970?) Toxicity of 2,4-D and Picloram 

to Fresh and Salt Water Algae. Proceeding’s North Central Weed Control 

Conference 1970. (Published Study Received Jan 13, 1986, Submitted by Dow 

Chemical under Accession No. 261128).

123-1 Seed germination/seedling emergence and vegetative vigor

MRID Citation Reference

41296501 Weseloh, J.; Stockdale, G. (1989) A Study To Determine the Effects of Picloram 

on Seed Germination, Seedling Emergence and Vegetative Vigor: Lab Project 

Number GH-P 1444; Protocol 89040. Unpublished study prepared by Dow 

Chemical U.S.A. Midland Field Research Station. 170 p. 

Accession No. 

261128

Ragab, M.T.H. (1975) Residues of Picloram in Soil and Their Effects on Crops. 

Canadian Journal of Soil Science. 55: 55-59. (Published Study Received January 

13, 1986, Submitted by Dow Chemical under Accession No. 261128).

40346508 Smith, L.L., Jr. and J. Geronimo (1984) Response of Seven Crops to Foliar 

Applications of Six Auxin-Like Herbicides. Down to Earth Vol. 40, No. 2 

August 1984. (Published Study Received January 13, 1986, Submitted by Dow 

Chemical under Accession No. 261128).

111517 Herr, D.E., E.W. Stroube and D.A. Ray (1966) Effect to TORDON Residues on 

Agronomic Crops. Down to Earth 21: 17-18. (Published Study Received January 

13, 1986, Submitted by Dow Chemical under Accession No. 261128).

43276601 Schwab, Dave (1994) Evaluating the Effects of Picloram on the Germination,

Emergence and Vegetative Vigor of Non-Target Terrestrial Plants. ABC 

Laboratories, Inc., Columbia, MO. DowElanco, Indianapolis, IN. ID No. 41404.

Effects to Russett potatoes

123-2 Aquatic plant growth

MRID Citation Reference

43230302 Boeri, R.; Kowalski, P.; Ward, T. (1994) Tordon K Herbicide: Toxicity to the 

Freshwater Diatom, Navicula pelliculosa: Lab Project Number: 436/DO: 

ES/2772. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 24 

p. 

43230303 Boeri, R.; Magazu, J.; Ward, T. (1994) Tordon 101 Herbicide: Toxicity to the 

Freshwater Diatom, Navicula pelliculosa: Lab Project Number: 433/DO: 

ES/2769. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 25 

p. Picloram TIPA + 2,4-D

43230304 Ward, T.; Kowalski, P.; Boeri, R. (1994) Access Herbicide: Toxicity to the 
Page 53 of 111

Marine Diatom, Skeletonema costatum: Lab Project Number: 431/DO: 

ES/2767. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 25 

p. Mixture Picloram and Triclopyr BEE

43230305 Boeri, R.; Kowalski, P.; Ward, T. (1994) Tordon K Herbicide: Toxicity to the 

Marine Diatom, Skeletonema costatum: Lab Project Number: 437/DO: 

ES/2773. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 24 

p. 

43230308 Boeri, R.; Kowalski, P.; Ward, T. (1994) Tordon K Herbicide: Toxicity to the 

Freshwater Blue-Green Alga, Anabaena flos-aquae: Lab Project Number: 

438/DO: ES/2774. Unpublished study prepared by T. R. Wilbury Laboratories, 

Inc. 25 p. 

129067 Elder, J.; Lembi, C.; Morre, D. (1970) Toxicity of 2,4-D and piclo- ram to 

fresh and salt water algae. Proceedings North Central Weed Control 

Conference 25:96-98. (Also In unpublished submis- sion received Jun 24, 

1983 under 464-502; submitted by Dow Chem- ical U.S.A., Midland, MI; 

CDL:250605-F) 

43230301 Boeri, R.L., P.L. Kowalski and T.J. Ward (1994) Access Herbicide: Toxicity 

to the Freshwater Diatom, Navicula pelliculosa. Laboratory Project No. 430-

DO. Conducted by T.R. Wilbury Laboratories, Inc., Marblehead, MA. 

Submitted by the Dow Chemical Company, Midland, MI. EPA MRID No. 

43230301.

43230311 Kirk, H.D, (1994) The Toxicity of Tordon K Herbicide Formulation to the 

Aquatic Plant, Duckweed Lemna gibba. Laboratory Project No. DECO-ES2764. Conducted by the Environmental Toxicology and Chemistry Research 

Laboratory, Health and Environmental Sciences, The Dow Chemical Co., 

Midland, MI. Submitted by DowElanco, Indianapolis, IN. EPA MRID No. 

43230311.

43230306 Boeri, R.L., J.P. Magazu and T.J. Ward (1994) Tordon 101Herbicide: Toxicity 

to the Marine Diatom, Skeletonema costatum. Laboratory Project No. 434-

DO. Conducted by T.R. Wilbury Laboratories, Inc., Marblehead, MA. 

Submitted by the Dow Chemical Company, Midland, MI. EPA MRID No. 

43230306.

Accession No. 

261128

McCarty, W.M. (1986?) Non-Target Area Phytotoxicity, Aquatic Plant 

Growth – Selenastrum capricornutum. Evaluation of the Toxicity of Technical 

Picloram to the Freshwater Green Alga. Prepared by Dow Chemical. 

(Unpublished Study Received June 13, 1986, Submitted by Dow Chemical 

under Accession No. 261128).

41407701 Hughes, J.S. (1990) The Toxicity of TORDON 101 TO Selenastrum 

capricornutum. Laboratory Project ID 0460-04-1100-4. Conducted by 

Malcolm Pirnie, Inc., Elmsford, NY. Submitted by DowElanco. EPA MRID 

No. 41407701.

124-1 Terrestrial field
Page 54 of 111

MRID Citation Reference

159234 Hilton, H.; Osgood, R. (19??) Tordon as a Selective Herbicide for Hawaiian 

Sugarcane. Unpublished study prepared by Hawaiian Sugar Planters 

Association. 25 p. 

29210 Schwartzbeck, R.A.; Irvine, W.T. (1969) Effect of Preemergent and 

Postemergent Applications of Tordon^(R)I Herbicide on 23 Varie- ties of 

Native Range Grasses. (Unpublished study received Aug 4, 1969 under 464-

407; submitted by Dow Chemical U.S.A., Mid- land, Mich.; CDL:003636-K) 

Accession No. 

261128

Hemphill, D.D. (1968) Performance of Vegetable Crops on an Area Treated 

with Tordon Herbicide. Down to Earth, 24(1): 2 and 24. (Published Study 

Received January 13, 1986, Submitted by Dow Chemical under Accession No. 

261128).

59420 Vanden Born, W.H. (1969) Picloram Residues and Crop Production. Canadian 

Journal of Plant Science Vol. 49: 628-629. (Published Study Received January 

13, 1986, Submitted by Dow Chemical under Accession No. 261128).

141-1 Honey bee acute contact

MRID Citation Reference

41366901 Hoxter, K.; Jaber, M. (1989) Tordon 101: An Acute Contact Toxicity Study with 

the Honey Bee: Project No. 103-313. Unpublished study prepared by Wildlife 

International Ltd. 16 p. 

129066 Doty, A. (1965) Some Observations of the Toxicity of Tordon Herbi- cide on 

Honey Bees. (Unpublished study received Jun 24, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-E) 

36935 Atkins, E.L., E.A. Greywood and R.L. Macdonald (1975) Toxicity of Pesticides 

and Other Agricultural Chemicals to Honey Bees: Laboratory Studies. By 

University of California, Dept. of Entomology. ?: UC, Cooperative Extension. 

(leaflet 2287, Published Study).

41369902 Hoxter, K. M.M. Thompson and M. Jaber (1989) Picloram (4-amino-3,5,6-

trichloropicolinic acid) K Salt (Technical): An Acute Contact Toxicity Study 

with the Honey Bee. Laboratory Project No. 103-305. Conducted by Wildlife 

International Ltd., Easton, MD. Submitted by the Dow Chemical Company, 

Midland, MI. EPA MRID No. 41369902.

Chronic Effects to Honeybees

111489 Morton, H.; Moffett, J. (1971) Influence of Herbicides on Reproduction of Honey 

Bees. (Abstract 216; unpublished study received Sep 26, 1974 under 464-323; 

prepared by Agricultural Research Service in cooperation with Univ. of Arizona, 

Agricultural Experiment Station, submitted by Dow Chemical U.S.A., Midland, MI; 
Page 55 of 111

CDL:120345-I) 

141-3 Aquatic Insect Larvae – acute toxicity

No MRID Sanders, H.O. and O.B. Cope (1968) The Relative Toxicities of Several Pesticides to 

Naiads of Three Species of Stoneflies. Limnol. Oceanogr. 13:112-117.

142-3 Simulated or Actual Field Testing

MRID Citation Reference

129079 Scott, T.; Schultz, H.; Eschmeyer, P.; eds. (1977) Environmental contaminant 

evaluation. Pages 20-22, In Fisheries and Wildlife Research 1977. Denver, CO: 

USFWS. (Also In unpublished sub- mission received Jun 24, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-S) 

Picloram, Benomyl, Acephate, Kepone

165-3 Bioconcentration

No MRID 

on DER Bidlack, H. D. 1980. BCF in Bluegill

Non Guideline Selections

82751 Somers, J.D. (1972) Influence of External Application of Pesticides on Egg 

Hatchability and Chick Viability. Master's thesis, Univ. of Guelph. (Unpublished 

study received Jun 6, 1973 under 1F1102; submitted by Dow Chemical Co., 

Indianapolis, Ind.; CDL: 090866-G) 

84027 Lynn, G.E. (1965) A review of toxicological information on tordon herbicides. 

Down to Earth 20(4):6-8. (Also~In~unpublished sub- mission received Nov 21, 

1967 under 8F0660; submitted by Dow Chemical Co., Indianapolis, Ind.; 

CDL:091155-B) 

111414 Leasure, J. (1965) An Investigation of Alleged Damage by Tordon in Irrigation 

Water to Crops in Virginia and North Carolina. (Un- published study received Nov 

6, 1967 under 8F0660; submitted by Dow Chemical Co., Indianapolis, IN; 

CDL:091158-C) 

111496 Pimentel, D. (1971) Ecological Effects of Pesticides on Non-target Species. By 

Executive Office of the President, Office of Sci- ence and Technology. Washington, 

DC: Executive Office of the President. (Pages 118-127 only; available from: U.S. 

Government Printing Office, Washington, DC 20402; published study; CDL: 

120345-Q) 

111501 Hay, J.; Grover, R.; Patterson, J.; et al. (1974) Picloram: The Effects of Its Use as a 

Herbicide on Environmental Quality. By National Research Council Canada, Assoc. 

Committee on Scientific Criteria for Environmental Quality, Subcommittee on 

Pesticides and Related Compounds. Ottawa, ON: Publications, NRCC. (Avail- able 

from: Publications, NRCC/CNRC, Ottawa, ON K1A 0R6; NRCC No. 13684; 

published study; CDL:120352-E) 

41145 Bond, C.E.; Wilson, D.C.; Malick, J. (1967) Aquatic Weed Control Progress Report 
Page 56 of 111

1967: Project 773. (Unpublished study received on unknown date under 8F0660; 

prepared by Oregon State Univ., Agricultural Experiment Station, Dept. of Fisheries 

and Wild- life, submitted by Dow Chemical U.S.A., Midland, Mich.; CDL: 094930-

G) 

111458 Bond, C.; Wilson, D.; Malick, J. (1967) Progress Report on Aquatic Weed Research 

(Project 773). (Unpublished study received Jun 28, 1979 under 0F0863; prepared by 

Oregon State Univ., Agricul- tural Experiment Station, Dept. of Fisheries and 

Wildlife, sub- mitted by Dow Chemical Co., Indianapolis, IN; CDL:098349-I) 

No MRID Parisot, T.J.(1968) Letter Report from T.J. Parisot. U.S. Fish and Wildlife Service to 

E.E. Kenaga, The Dow Chemical Company.

No MRID Scott, T.G., H.C. Schultz and P.H. Eschmeyer (1977) Fisheries and Wildlife 

Research: Environmental Contaminant Evaluation. Edit. U.S. Fish and Wildlife 

Service.

No MRID (1982?) National Research Council of Canada. Picloram: The Effects of its use as a 

Herbicide on Environmental Quality. Publication No. NRCC13684. 128p.

No MRID Kenaga, E. (1969) TORDON® Herbicide – Evaluation of Safety to Fish and Birds. 

Down to Earth 25: 5-9.

No MRID Bohmont, B.L. (1967) Toxicity of Herbicides to Livestock, Fish, Honebees and 

Wildlife. PROC. WEST. Weed Cont. 21: 25-27.

5012893-

MRID not 

found in 

OPPIN

Giban J. 1972 Dangers to Game from Herbicide Application

005101 Picloram Fate Chemistry Bibliography

161-1 Hydrolysis

MRID Citation Reference

23103 Baur, J.R.; Bovey, R.W.; McCall, H.G. (1973) Thermal and ultravio- let loss of 

herbicides. Archives of Environmental Contamination and Toxicology 1(4):289-

302. (Also~In~unpublished submission received Apr 8, 1976 under 876-203; 

submitted by Velsicol Chemi- cal Corp., Chicago, Ill.; CDL:235226-T) 

111428 Dow Chemical Co. (1969) ?Study: Picloram Residues in Soil & Water|. 

(Compilation; unpublished study received Apr 30, 1970 under 0F0863; 

CDL:091491-A) 

131365 Hamaker, J. (1976) The Hydrolysis of Picloram in Buffered Distilled Water: GS1460. (Unpublished study received Aug 9, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL: 251038-A) 

161-2 Photodegradation-water
Page 57 of 111

MRID Citation Reference

164943 Woodburn, K.; Fontaine, D.; Bjerke, E. (1986) The Photolysis of Picloram in Dilute 

Aqueous Solution: No. GH-C 1820. Unpublish- ed study prepared by Dow Chemical 

U.S.A. 58 p. 

410925

01

164960 Woodburn, K.; Fontaine, D. (1986) The Photolysis of Picloram Isooc- tyl Ester in 

Dilute Aqueous Solution: No. GH-C 1834. Unpublish- ed study prepared by Dow 

Chemical U.S.A. 41 p. 

460275

01

Cook, W. (2003) Aqueous Photolysis of Picloram in pH 5 Buffer and Natural Water 

Under Xenon Light. Project Number: 000385. Unpublished study prepared by Dow 

Agrosciences LLC. 76 p.

111506 Plimmer, J. (1970) The photochemistry of halogenated herbicides. Pages 47-74, In 

Residue Reviews. Edited by W. Mullison. ?S.l.:s.n.|. (Also In unpublished submission 

received Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, 

MI; CDL:120352-J) 

428119

01

Batzer, F.R. and R.N. Lubinski (1993) Aqueous Photolysis of Picloram-IOE. 

Performed by DowElanco North American Chemistry Laboratory, 9410 Zionsville 

Road, Indianapolis, IN. 46268-1053. Study ID ENV93003.

111513 Hedlund, R. (1970) The Rate of Photodegradation of Picloram in Aqueous Systems: 

GS-1089. (Unpublished study received Sep 26, 1974 under 464-323; submitted by 

Dow Chemical U.S.A., Midland, MI; CDL:120317-C) 

111515 Hedlund, R.; Youngson, C. (1972) The rates of photodecomposition of picloram in 

aqueous systems. Advances in Chemistry Series (111):159-172. (Also In unpublished 

submission received Sep 26, 1974 under 464-323; submitted by Dow Chemical 

U.S.A.; Midland, MI; CDL:120317-E) 

44010 Gear, J.R.; Zerr, R.; Michel, J.; et al. (1973) Decomposition of Picloram in Aqueous 

Solutions under Ultraviolet and Sunlight Ir- radiation. (Unpublished study received 

May 5, 1975 under 464- 323; prepared by Univ. of Saskatchewan, Dept. of Chemistry 

and Canada, Dept. of Agriculture, Regina Research Station, submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:221997-K) 

44020 Michel, J.; Grover, R.; Gear, J.R. (1973) Kinetics of Picloram Pho- tolysis in Aqueous 

Solutions. (Unpublished study received May 5, 1975 under 464-323; prepared by 

Univ. of Saskatchewan, Dept. of Chemistry and Canada, Dept. of Agriculture, Regina 

Research Station, submitted by Dow Chemical U.S.A., Midland, Mich.; CDL: 221997-

V) 

46856 Mosier, A.R.; Guenzi, W.D. (1973) Picloram photolytic decomposi- tion. Journal of 

Agricultural & Food Chemistry 21(5):835-837. (Also~In~unpublished submission 
Page 58 of 111

received May 5, 1975 under 464- 323; submitted by Dow Chemical U.S.A., Midland, 

Mich.; CDL: 221997-W) 

59410 Redemann, C.T. (1966) Photodecomposition Rate Studies of 4-Amino- 3,5,6-

trichloropicolinic acid: Report GS-753. (Unpublished study received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-A) 

59423 Youngson, C.R.; Goring, C.A.I. (1967) Decomposition of Tordon Herbicide by 

Sunlight in Water and Soil: Report GS-850. (Un- published study received Sep 26, 

1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:120353-N) 

59425 Youngson, C.R. (1968) Effect of Source and Depth of Water, and Concentration of 4-

Amino-3,5,6-trichloropicolinic acid on Rate of Photodecomposition by Sunlight. 

(Unpublished study received Sep 26, 1974 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:120353-P) 

111415 Youngson, C.; Goring, C. (1967) Decomposition of Tordon Herbicide by Sunlight in 

Water and Soil. (Unpublished study received Nov 6, 1967 under 8F0660; submitted by 

Dow Chemical Co., Indian- apolis, IN; CDL:091158-D) 

111416 Hamaker, J. (1964) Decomposition of Aqueous Tordon Solutions by Sunlight. 

(Unpublished study received Nov 6, 1967 under 8F0660; submitted by Dow Chemical 

Co., Indianapolis, IN; CDL:091158-E) 

111417 Redemann, C. (1966) Photodecomposition of Tordon Herbicide. (Un- published study 

received Nov 6, 1967 under 8F0660; submitted by Dow Chemical Co., Indianapolis, 

IN; CDL:091158-F) 

111476 Hall, R.; Giam, C.; Merkle, M. (1968) The photolytic degradation of picloram. Weed 

Res. 8:292-297. (Also In unpublished submission received Sep 26, 1974 under 464-

323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120318-Y) 

111477 Hamaker, J. (1964) Decomposition of Aqueous Tordon Solutions by Sunlight: GH652. (Unpublished study received Sep 26, 1974 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:120318-Z) 

111512 Hedlund, R.; Youngson, C. (1968) Solar Photodecomposition Studies with Picloram in 

Aqueous Solutions: GS-963. (Unpublished study received Sep 26, 1974 under 464-

323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120317-B) 

111514 Hedlund, R. (1971) The Rate of Photodegradation of Picloram in Aqueous Systems. II. 

Effect of Several Depths: GS 1122. (Un- published study received Sep 26, 1974 under 

464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120317-D) 

123280 Dow Chemical U.S.A. (1978) ?Chemical Study: Picloram|. (Compila- tion; 

unpublished study received Dec 9, 1982 under 464-502; CDL: 248983-A) 

128964 Gear, J.; Michel, J.; Grover, R. (1982) Photochemical degradation of Picloram. Pestic. 

Sci. 13:189-194. (Also In unpublished study received Jun 16, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250517-S) 
Page 59 of 111

128965 Glass, B. (1974) Photosensitization and Luminesence Studies of Picloram. 

(Unpublished study received Jun 16, 1983 under 464- 502; prepared by U.S. 

Agricultural Research Service, Agri- cultural Chemicals Management Laboratory, 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250517-T) 

161-3 Photodegradation-soil

MRID Citation Reference

17934 Hance, R.J. (1967) Decomposition of herbicides in the soil by non- biological chemical 

processes. J. Sci. Fd Agric. 18(?/Nov):544- 547. (Also~In~unpublished submission 

received Aug 20, 1976 under 39445-1; submitted by American Carbonyl, Inc., Tenafly, 

N.J.; CDL:228229-AX) 

59410 Redemann, C.T. (1966) Photodecomposition Rate Studies of 4-Amino- 3,5,6-

trichloropicolinic acid: Report GS-753. (Unpublished study received Sep 26, 1974 under 

464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-A) 

59423

repeated

Youngson, C.R.; Goring, C.A.I. (1967) Decomposition of Tordon Herbicide by Sunlight 

in Water and Soil: Report GS-850. (Un- published study received Sep 26, 1974 under 

464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-N) 

69075 Hamaker, J.W. (1975) Distribution of Picloram in a High Organic Sediment-water 

System: Uptake Phase: GS-1432. (Unpublished study received Mar 9, 1977 under 464-

541; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:228626-B) 

102567 Youngson, C.; Hamaker, J.; Goring, C. (1964) Sorption, Leaching, and Decomposition of 

4-Amino-3,5,6-trichloropicolinic Acid in Soils. (Unpublished study received Jun 19, 1964 

under 464-306; submitted by Dow Chemical U.S.A., Midland, MI; CDL:003500-A) 

111415 Youngson, C.; Goring, C. (1967) Decomposition of Tordon Herbicide by Sunlight in 

Water and Soil. (Unpublished study received Nov 6, 1967 under 8F0660; submitted by 

Dow Chemical Co., Indian- apolis, IN; CDL:091158-D) 

111425 Youngson, C.; Goring, C.; Meikle, R.; et al. (1967) Factors In- fluencing the 

Decomposition of Tordon Herbicide in Soils. (Un- published study received Nov 6, 1967 

under 8F0660; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091156-J) 

111427 Hamaker, J. (1967) Reaction Kinetics for the Detoxification of Tordon in Soil. 

(Unpublished study received Nov 6, 1967 under 8F0660; submitted by Dow Chemical 

Co., Indianapolis, IN; CDL: 091156-M) 

111452 Bohmont, B.; Fults, J. (1968) A Test of Picloram Degradation under Three Soil Moisture 

Treatments. (Unpublished study received Apr 4, 1970 under 0F0863; submitted by Dow 

Chemical Co., Indi- anapolis, IN; CDL:091492-AJ) 

111453 Plimmer, J.; Kearney, P. (1968) Decarboxylation of Picloram during Extraction. (U.S. 

Agricultural Research Service; unpublished study; CDL:091492-AK) 

111464 Baur, J.; McCall, H.; Bovey, R. (1969) Ultraviolet Degradation of Picloram. Annual rept., 

1969. (Unpublished study received Sep 26, 1974 under 464-323; prepared by Texas A & 
Page 60 of 111

M Univ., Agri- cultural Experiment Station, submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:120318-D) 

111477

111478 Hamaker, J. (1969) Rates of Photodecomposition of 4-Amino-3,5,6- trichloropicolinic 

Acid in Some Natural Waters: GS-998. (Un- published study received Sep 26, 1974 under 

464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120318-AD) 

112011 Redemann, C.; Meikle, R.; Hamilton, P.; et al. (1968) The Fate of 4-amino-3,5,6-

trichloropicolinic Acid in Spring Wheat and Soil. (Unpublished study received Apr 4, 

1970 under 0F0863; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-L) 

140314 Bauer, J.R.; Baker, R.D. (19??) Ultraviolet Degradation of Piclor- am, 2,4,5-T and 

Dicamba. (Unpublished study received Mar 9, 1977 under 464-423; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:228627-E) 

140321 Grover, R. (1971) Adsorption of picloram by soil colloids and var- ious other adsorbents. 

Weed Science 19(4):417-418. (Also~In~ unpublished submission received Mar 9, 1977 

under 464-423; sub- mitted by Dow Chemical U.S.A., Midland, Mich.; CDL:228627-W) 

157175 Fontaine, D.; Woodburn, K. (1986) Photodegradation Study of Piclo- ram on Catlin Soil 

Surface: GH-C 1793. Unpublished study pre- pared by Dow Chemical USA. 17 p. 

412601

01

Racke, K.; McGovern, P.; Shepler, K.; et al. (1989) Photodegrada- tion of Picloramisooctyl Ester on Soil by Natural Sunlight: PTRL Report No. 157W-1: PTRL Project No. 

157W. Unpublished study prepared by Dow Chemical U.S.A. 77 p. 

162-1 Aerobic soil metabolism

MRID Citation Reference

28395 Corbin, F.T.; Upchurch, R.P. (19??) Influence of pH on detoxication of herbicides in soil. 

Weeds 15(4):370-377. (Also~In~unpub- lished submission received Jan 5, 1968 under 

8F0725; submitted by Velsicol Chemical Corp., Chicago, Ill.; CDL:091252-AL) 

59411 Redemann, C.T.; Meikle, R.W.; Hamilton, P.; et al. (1968) The fate of 4-Amino-3,5,6-

trichloropicolinic acid in spring wheat and soil. Bulletin of Environmental Contamination 

& Toxicology 3 (2):80-96. (Also~In~unpublished submission received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-B) 

59412 Rieck, C.E. (1969) Microbial Degradation of 4-Amino-3,5,6-tri- chloropicolinic acid in 

Soils and in pure Cultures of Soil Isolates. Doctoral dissertation, Univ. of Nebraska, Dept. 

of Agronomy. (Unpublished study received Sep 26, 1974 under 464- 323; submitted by 

Dow Chemical U.S.A., Midland, Mich.; CDL: 120353-C) 

59424 Youngson, C.R.; Goring, C.A.I.; Meikle, R.W.; et al. (1967) Factors influencing the 

decomposition of Tordon herbicide in soils. Down to Earth 23(2):3-11. (Also In 

unpublished submission re- ceived Sep 26, 1974 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:120353-O) 
Page 61 of 111

59426 Youngson, C.R. (1969) Are Soil Microorganisms the Chief Source of Decomposition of 

Tordon in Soil: Report GS 1006. (Unpublished study received Sep 26, 1974 under 464-

323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-Q) 

111420 Arnold, W.; Santelmann, P.; Lynd, J. (1966) Picloram and 2,4-D effects with aspergillus 

niger proliferation. Weeds 14(Jan): 89-90. (Also In unpublished submission received Nov 

6, 1967 under 8F0660; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091156-

B) 

111425 Youngson, C.; Goring, C.; Meikle, R.; et al. (1967) Factors In- fluencing the 

Decomposition of Tordon Herbicide in Soils. (Un- published study received Nov 6, 1967 

under 8F0660; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091156-J) 

111427 Hamaker, J. (1967) Reaction Kinetics for the Detoxification of Tordon in Soil. 

(Unpublished study received Nov 6, 1967 under 8F0660; submitted by Dow Chemical 

Co., Indianapolis, IN; CDL: 091156-M) 

111446 Hamaker, J.; Youngson, C.; Goring, C. (1968) Rate of detoxification of 4-amino-3,5,6-

trichloropicolinic acid in soil. Weed Res. 8 (1):46-57. (Also In unpublished submission 

received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., Indianapolis, IN; 

CDL:091492-AB) 

111447 Youngson, C. (1967) A Comparison of Decomposition of Carboxyl- and Carboxyl and 

Ring Labeled C14 4-Amino-3,5,6-Trichloropicolinic Acid in Clay Soil: Report No. GS886. (Unpublished study re- ceived Apr 4, 1970 under 0F0863; submitted by Dow 

Chemical Co., Indianapolis, IN; CDL:091492-AD) 

111448 Youngson, C.; Meikle, R. (1969) A Comparison of the Rates of Loss of 4-Amino-6-

Hydroxy-3,5-Dichloropicolinic Acid and ... ?Tordon| from Soil. (Unpublished study 

received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., Indianapolis, IN; 

CDL: 091492-AE) 

111451 Dow Chemical Co. (1968) ?Picloram: Residues in Soil|. (Compila- tion; unpublished 

study received Apr 4, 1970 under 0F0863; CDL:091492-AI) 

111483 Meikle, R.; Youngson, C.; Hedlund, R. (1970) The Decomposition of Picloram in Soil: 

Effect of Temperature: GS-1093. (Unpublished study received Sep 26, 1974 under 464-

323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120345-A) 

111484 Meikle, R.; Youngson, C.; Hedlund, R. (1970) Decomposition of Picloram in Soil: Effect 

of Different Soils and Kinetics in a Single Soil: GS-1082. (Unpublished study received 

Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:120345-B) 

111486 Meikle, R.; Youngson, C.; Hedlund, R. (1971) Decomposition of Picloram in Soil: A 

Comparison of Anaerobic with Aerobic Soil Microorganisms: GS-1103. (Unpublished 

study received Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:120345-D) 

111502 Dow Chemical U.S.A. (1973) ?Decomposition Rates and Extraction Procedure for 

Picloram and Other Compounds in Soil|. (Compi- lation; unpublished study received Sep 
Page 62 of 111

26, 1974 under 464-323; CDL:120352-F) 

111503 Meikle, R.; Youngson, C.; Hedlund, R. (1970) The Decomposition of Picloram in Soil: 

Effect of Extraneous Material Added to Soil. (Unpublished study received Sep 26, 1974 

under 464-323; sub- mitted by Dow Chemical U.S.A., Midland, MI; CDL:120352-G) 

111504 Meikle, R.; Youngson, C.; Hedlund, R.; et al. (1973) Measurement and prediction of 

Picloram disappearance rates from soil. Weed Science 21(6):549-555. (Also In 

unpublished submission received Sep 26, 1974 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:120352-H) 

111505 Meikle, R.; Youngson, C.; Hedlund, R.; et al. (1974) Decomposition of picloram by soil 

microorganisms: A proposed reaction se- quence. Weed Science 22(3):263-268. (Also In 

unpublished submission received Sep 26, 1974 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:120352-I) 

111530 Meikle, R.; Youngson, C.; Hedlund, R. (1970) Decomposition of Picloram in Soil: Effect 

of a Pre-moistened Soil: GS-1097. (Unpublished study received Sep 26, 1974 under 464-

323; sub- mitted by Dow Chemical U.S.A., Midland, MI; CDL:120317-Y) 

111531 Meikle, R.; Youngson, C.; Hedlund, R. (1970) The Decomposition of Picloram in Soil: 

Effect of Soil Depth on the Rate: GS-1098. (Unpublished study received Sep 26, 1974 

under 464-323; sub- mitted by Dow Chemical U.S.A., Midland, MI; CDL:120317-Z) 

128976 McCall, P.; Jeffries, T. (1978) Aerobic and Anaerobic Soil Degrada- tion of 14Cpicloram. Final rept. (Unpublished study received Jun 16, 1983 under 464-502; submitted 

by Dow Chemical U.S.A., Midland, MI; CDL:250518-A) 

128992 Youngson, C. (1969) A Comparison of a Tropical and a Continental Soil for Their Ability 

to Decompose Tordon Herbicide: Report No. GS-1036. (Unpublished study received Jun 

16, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

250518-R) 

128993 Laskowski, D.; Youngson, C. (1970) An Evaluation of the Ability of Soil Samples 

Obtained in Profile from Different Depths for Their Ability To Decompose Picloram: 

Report No. GS-1046. (Unpublished study received Jun 16, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250518-S) 

37877 Meikle, R.W. (1972) Decomposition: Qualitative relationships in or- ganic chemicals in 

the soil environment. Page 181,~In~Or- ganic Chemicals in the Soil Environment: 

Volume 1. Edited by C.A.I. Goring and J.W. Hamaker. N.P. (Also~In~unpublished 

submission received Jun 6, 1973 under 2F1265; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:092164-K) 

37879 Meikle, R.W.; Youngson, C.R.; Hedlund, R.T. (1970) The Decomposi- tion of Picloram 

in Soil: Comparison of the Rate of Radioactive Carbon dioxide Evolution for Carboxyland Totally-labelled Pic- loram: GS 1088. (Unpublished study received Jun 6, 1973 under 

2F1265; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL: 092164-M) 

37883 Meikle, R.W. (1973) Comparison of the Decomposition Rates of Piclo- ram and 4-

Amino-2,3,5-trichloropyridine in Soil: GS-1321. (Un- published study received Jun 6, 
Page 63 of 111

1973 under 2F1265; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:092164-

S) 

38481 Meikle, R.W.; Youngson, C.R.; Hedlund, R.T. (1970) Decomposition of Picloram in Soil: 

Comparison of the Decomposition Rates of Pic- loram and Its 6-Hydroxy Derivative: GS1092. (Unpublished study received Jun 6, 1973 under 2F1265; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:092164-R) 

41133 Banks, V.S.; Meikle, R.W. (1967) Tordon Metabolism in Soil. (Un- published study 

received Nov 6, 1967 under 0F0863; submitted by Dow Chemical U.S.A., Midland, 

Mich.; CDL:094525-AU) 

111532 Meikle, R.; Youngson, C.; Hedlund, R. (1970) The Decomposition of Picloram in Soil: 

Effect of Soil Moisture on the Rate of Picloram Decomposition: GS-1094. (Unpublished 

study received Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:120317-AA) 

162-2 Anaerobic soil metabolism

128976 McCall, P.; Jeffries, T. (1978) Aerobic and Anaerobic Soil Degradation of 14C-picloram. 

Final rept. (Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250518-A) 

163-1 Leach/adsorp/desorption

MRID Citation Reference

4039 Starr, R.I.; Cunningham, D.J. (1966?) Translocation and Degradation of 4-Aminopyridine 

in Corn Plants. (Unpublished study received Jan 3, 1973 under 1F1013; prepared by U.S. 

Fish and Wildlife Service, Denver Wildlife Research Center, submitted by Phillips 

Petroleum Co., Bartlesville, Okla.; CDL:091757-T) 

17934 Hance, R.J. (1967) Decomposition of herbicides in the soil by non- biological chemical 

processes. J. Sci. Fd Agric. 18(?/Nov):544- 547. (Also~In~unpublished submission 

received Aug 20, 1976 under 39445-1; submitted by American Carbonyl, Inc., Tenafly, 

N.J.; CDL:228229-AX) 

23108 Khan, S.U. (1973) Interaction of humic acid with Chlorinated phenoxyacetic and benzoic 

acids. Environmental Letters 4(2): 141-148. (Also~In~unpublished submission received 

Apr 8, 1976 under 876-203; submitted by Velsicol Chemical Corp., Chicago, Ill., 

CDL:235226-AB) 

27139 Weidner, C.W. (1974) Degradation in Groundwater and Mobility of Herbicides. Master's 

thesis, Univ. of Nebraska, Dept. of Agron- omy. (Unpublished study received Jul 19, 

1978 under 201-403; submitted by Shell Chemical Co., Washington, D.C.; CDL:234472-

O) 

27140 Lavy, T.L. (1974) Mobility and Deactivation of Herbicides in Soil- Water Systems: 

Project A-024-NEB. (Available from: National Technical Information Service, 

Springfield, VA: PB-238 632; un- published study received Jul 19, 1978 under 201-403; 

prepared by Univ. of Nebraska, Water Resources Research Institute, sub- mitted by Shell 
Page 64 of 111

Chemical Co., Washington, D.C.; CDL:234472-P) 

28409 May, J.W. (1968) Summary of Results of Dicamba and Picloram Behav- ior in Colorado 

Soils. Ph.D. thesis, Colorado State Univ. (Un- published study received Jul 13, 1970 

under 876-25; submitted by Velsicol Chemical Corp., Chicago, Ill.; CDL:126372-N) 

44003 Biggar, J.W.; Cheung, M.W. (1973) Adsorption of Picloram (4-Amino- 3,5,6-

trichloropicolinic acid) on panoche, Ephrata, and palouse soils: A thermodynamic 

approach to the adsorption mechanism. Soil Science Society of America Proceedings 

37:863-868. (Also ?~In~unpublished submission received May 5, 1975 under 464-323; 

submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:221997-C) 

44006 Brady, H.A. (1965) The Retention of Some Commercial Herbicides by a Hagerstown Silt 

Loam Soil. Doctoral dissertation, Pennsylvania State Univ., Dept. of Agronomy. 

(Unpublished study received May 5, 1975 under 464-323; submitted by Dow Chemical 

U.S.A., Mid- land, Mich.; CDL:221997-F) 

44007 Davidson, J.M.; Chang, R.K. (1972) Transport of Picloram in rela- tion to soil physical 

conditions and pore-water velocity. Soil Science Society of America Proceedings 36:257-

261. (Also~In~un- published submission received May 5, 1975 under 464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:221997-G) 

44011 Van Genuchten, M.T.; Davidson, J.M.; Wierenga, P.J. (1974) An eval- uation of kinetic 

and equilibrium equations for the prediction of pesticide movement through porous 

media. Soil Science Socie- ty of America Proceedings 38:29-35. (Also~In~unpublished 

sub- mission received May 5, 1975 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:221997-L) 

44015 Grover, R. (1973) Movement of picloram in soil columns. Canadian Journal of Soil 

Science 53(3):307-314; Taken from: ?Without Ti- tle| ? (? ):7 (Abstract no. 74-0026) 

(Also~In~unpublished sub- mission received May 5, 1975 under 464-323; submitted by 

Dow Chemical U.S.A., Midland, Mich.; CDL:221997-P) 

44017 Helling, C.S. (1971) Pesticide mobility in soils: II. Applications of soil thin-layer 

chromatography. Soil Science Society of America Proceedings 35:737-748. (Also In 

unpublished submission received May 5, 1975 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:221997-S) 

44021 Norris, L.A. (1970) The kinetics of adsorption and desorption of 2,4-D, 2,4,5-T, 

Picloram, and Amitrole on forest floor material. Pages 103-105,~In~Research Progress 

Report, Western Society of Weed Science 1970. N.P. (Also~In~unpublished submission 

re- ceived May 5, 1975 under 464-323; submitted by Dow Chemical U.S.A., Midland, 

Mich.; CDL:221997-X) 

59414 Scifres, C.J.; Burnside, O.C.; McCarty, M.K. (1969) Movement and persistence of 

Picloram in pasture soils of Nebraska. Weed Science 17(4):486-488. 

(Also~In~unpublished submission re- ceived Sep 26, 1974 under 464-323; submitted by 

Dow Chemical U.S.A., Midland, Mich.; CDL:120353-E) 

59962 Uprichard, S.D.; Gilchrist, A.J. (1975) The Influence of Soil Types on the Persistence and 
Page 65 of 111

Leaching of Dowco 290. (Unpublished study received Nov 12, 1980 under 464-563; 

prepared by Dow Chem- ical Europe, S.A., England, submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:099727-D) 

69075 Hamaker, J.W. (1975) Distribution of Picloram in a High Organic Sediment-water 

System: Uptake Phase: GS-1432. (Unpublished study received Mar 9, 1977 under 464-

541; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:228626-B) 

95245 Grover, R. (1973) Movement of picloram in soil columns. Canadian Journal of Soil 

Science 53(Aug):307-314. (Also~In~unpublished submission received Nov 14, 1977 

under 464-448; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:096642-G) 

95247 Grover, R. (1977) Mobility of dicamba, picloram and 2,4-D in soil columns. Weed 

Science 25(2):159-162. (Also~In~unpublished submission received Nov 14, 1977 under 

464-448; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:096642-J) 

102567 Youngson, C.; Hamaker, J.; Goring, C. (1964) Sorption, Leaching, and Decomposition of 

4-Amino-3,5,6-trichloropicolinic Acid in Soils. (Unpublished study received Jun 19, 1964 

under 464-306; submitted by Dow Chemical U.S.A., Midland, MI; CDL:003500-A) 

111422 Hamaker, J.; Goring, C.; Youngson, C. (1966) Sorption and leaching of 4-amino-3,5,6-

trichloropicolinic acid in soils. Advances in Chemistry Series (60):23-37. (Also In 

unpublished submission received Nov 6, 1967 under 8F0660; submitted by Dow 

Chemical Co., Indianapolis, IN; CDL:091156-G) 

111424 Youngson, C. (1964) Effect of Weekly Applications of Water over a 37-Week Period on 

Leaching of Tordon Herbicide through Soils. (Unpublished study received Nov 6, 1967 

under 8F0660; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091156-I) 

111428 Dow Chemical Co. (1969) ?Study: Picloram Residues in Soil & Water|. (Compilation; 

unpublished study received Apr 30, 1970 under 0F0863; CDL:091491-A) 

111473 Grover, R. (1971) Adsorption of picloram by soil colloids and various other adsorbents. 

Weed Science 19(4):417-418. (Also In unpublished submission received Sep 26, 1974 

under 464-323; sub- mitted by Dow Chemical U.S.A., Midland, MI; CDL:120318-V) 

111485 Meikle, R.; Youngson, C.; Hedlund, R. (1971) Decomposition of Picloram in Soil: Effect 

of Temperature, Moisture, Concentra- tion, and Percent Organic Matter, Using a 

Factorially Designed Experiment: GS-1104. (Unpublished study received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120345-C) 

111516 Helling, C. (1971) Pesticide mobility in soils I. Parameters of thin-layer chromatorgraphy. 

Soil Science Society of America Proceedings 35:732-747. (Also In unpublished 

submission re- ceived Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:120317-F) 

111528 McCall, H.; Bovey, R.; McCully, M; et al. (1972) Adsorption and desorption of picloram, 

trifluralin, and paraquat by ionic and nonionic exchange resins. Weed Science 20(3):250-

255. (Also In unpublished submission received Sep 26, 1974 under 464-323; submitted 

by Dow Chemical U.S.A., Midland, MI; CDL:120317-U) 
Page 66 of 111

116623 Khan, S. (1973) Equilibrium and Kinetic studies of the adsorption of 2,4-D and picloram 

on humic acid. Canadian Journal of Soil Science 53:429-434. (Also In unpublished 

submission received Oct 21, 1982 under 11683-EX-2; submitted by U.S. Dept. of the 

Interior, Washington, DC; CDL:248614-R) 

128949 Biggar, J.; Mingelgrin, U.; Cheung, M. (1978) Equilibrium and Ki- netics of adsorption 

of Picloram and Parathion with soils. J. Agric. Food Chem. 26(6):1306-1312. (Also In 

unpublished submission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-C) 

128959 Cheung, M.; Mingelgrin, U.; Biggar, J. (1979) Equilibrium and ki- netics of desorption of 

Picloram and Parathion in soils. J. Agric. Food Chem. 27(6):1201-1206. (Also In 

unpublished sub- mission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-M) 

128960 Davidson, J.; McDougal, J. (1973) Experimental and predicted move- ment of three 

herbicides in a water-saturated soil. J. Environ. Quality 2(4):428-433. (Also In 

unpublished submission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-N) 

128973 Kuo, E.; Volk, V. (1972) Mobility and Adsorption of Picloram and 2,4-D in Western 

Soils. (Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517AD) 

128974 LaFleur, K. (1979) Sorption of pesticides by model soils and agro- nomic soils: Rates and 

equilibria. Soil Science 127(2):94-101. (Also In unpublished submission received Jun 16, 

1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

250517AE) 

128977 McCall, P. (1978) Desorption Kinetics of Picloram. (Unpublished study received Jun 16, 

1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL:250518-B) 

128983 Ping, C.; Cheng, H.; McNeal, B. (1975) Variations in picloran leaching patterns for 

several soils. Soil Science Society of America Proceedings 39(3):470-473. (Also In 

unpublished submis- sion received Jun 16, 1983 under 464-502; submitted by Dow 

Chem- ical U.S.A., Midland, MI; CDL:250518-H) 

128991 Yoshida, T.; Castro, T. (1975) Degradation of 2,4-D, 2,4,5-T, and picloram in two 

Philippine soils. Soil Science and Plant Nutri- tion 21(4):397-404. (Also In unpublished 

submission received Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250518-Q) 

128998 Zimdahl, R. (1975) Column Leaching Studies with Triclopyr and Pi- cloram: A Report. 

(Unpublished study received Jun 16, 1983 un- der 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL: 250518-X) 

131366 Gaynor, J. (1971) Surfactant Effects on Bromacil and Picloram Ad- sorption by Oregon 

Soils. (Unpublished study received Aug 9, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:251038-B) 

134404 Corbin, F.; Upchurch, R. (1967) Influence of pH on Detoxication of Herbicides in Soil. 
Page 67 of 111

Weeds 15: 370-377. (Also In unpublished submission received Nov 3, 1971 under 

unknown admin. no.; sub- mitted by Union Carbide Agricultural Products Co., Inc., Research Triangle Park, NC; CDL:120413-E)

140316 Cheng, H.H. (1971) Picloram in soil: Extraction and mechanism of adsorption. Bulletin 

of Environmental Contamination & Toxi- cology 6(1):28-33. (Also~In~unpublished 

submission received Mar 9, 1977 under 464-423; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:228627-L) 

141646 Evans, J.; Duseja, D. (1973) Herbicide contamination of surface runoff waters. Prepared 

by Utah State Univ. for the Environ- mental Protection agency: Project No. 13030 EDJ. 

Available from the National Technial Information Service. 107 p. 

160126 Oliver, G.; Bjerke, E.; Gantz, R. (1986) Field Dissipation and Leaching Study for Grazon 

P+L Herbicide: GH-C 1819. Unpub- lished study prepared by Dow Chemical USA. 55 p. 

162051 Oliver, G. (1986) Evaluation of Leaching Potential of Soils in Major Mesquite Markets of 

Texas: GH-C 1822. Unpublished study prepared by Dow Chemical U.S.A. 19 p. 

501665

2

Helling, C.S. (1971) Pesticide mobility in soils: II_ Applications of soil thin-layer 

chromatography. Proceedings of the Soil Science Society of America 35(5):737-743. 

403463

13

Laskowski, D.; Zindahl, R. (1975) Private Communication to Laskow- ski, ...: Attached is 

a Report on Column Leaching Studies with Triclopyr and Picloram. Unpublished study 

prepared by Colorado State Univ. 40 p. 

412096

01

Racke, K. (1989) An Adsorption/Desorption Study of Picloram: Proje- ct ID GH-C 2218: 

Protocol No. 88129. Unpublished study prepared by Dow Chemical Co. 61 p. 

453718

26

Weber, J.; Miller, C. (1999) Organic Chemical Movement Over and Through Soil. 

Unpublished study prepared by North Carolina State University and University of North 

Carolina. 33 p. 

4129640

1

Racke, K.D. (1989) An Adsorption/Desorption Study of Picloram-isooctylester. 

November 1, 1989, Performing Laboratory, Agricultural Chemistry R&D Laboratories 

North American Agricultural Products Department Dow Chemical U.S.A. Midland, 

Michigan 48641-1706, Laboratory Project ID GH-C2263.

Not 

provided

Bush, P.B. Field Dissipation and Lea- Studies in a Northern Rangeland

Enviromt: Picloram/Clopyralid and Fluoxypyr

163-2 Volatility - lab

MRID Citation Reference

164-1 Terrestrial field dissipation

MRID Citation Reference
Page 68 of 111

23094 Burnside, O.C.; Wicks, G.A.; Fenster, C.R. (1971) Dissipation of Dicamba, Picloram, and

2,3,6-TBA across Nebraska. Weed Science 19(4):323-325. (Also~In~unpublished 

submission received Apr 8, 1976 under 876-203; submitted by Velsicol Chemical Corp., 

Chica- go, Ill.; CDL:235226-E) 

28409 May, J.W. (1968) Summary of Results of Dicamba and Picloram Behav- ior in Colorado 

Soils. Ph.D. thesis, Colorado State Univ. (Un- published study received Jul 13, 1970 under 

876-25; submitted by Velsicol Chemical Corp., Chicago, Ill.; CDL:126372-N) 

29309 Hamilton, K.C.; Arle, H.F. (1968) Herbicide residues in irrigated soils. Progressive 

Agriculture in Arizona XXI(2):16-17. (Also ?~In~unpublished submission received May 

30, 1973 under 6308-33; submitted by Ansul Chemical Co., Weslaco, Tex.; CDL:008662-

G) 

44006 Brady, H.A. (1965) The Retention of Some Commercial Herbicides by a Hagerstown Silt 

Loam Soil. Doctoral dissertation, Pennsylvania State Univ., Dept. of Agronomy. 

(Unpublished study received May 5, 1975 under 464-323; submitted by Dow Chemical 

U.S.A., Mid- land, Mich.; CDL:221997-F) 

44014 Goring, C.A.I.; Youngson, C.R.; Hamaker, J.W. (1966) Residues of Tordon in Soil from 

Field Experiments Treated with Tordon and Sampled at Various Intervals after Treatment. 

Includes undated method entitled: Bioassay method for the determination of resi- dues of 

Tordon herbicide in soil. (Unpublished study received May 5, 1975 under 464-323; 

submitted by Dow Chemical U.S.A.; CDL:221997-O) 

44018 Lutz, J.F.; Byers, G.E.; Sheets, T.J. (1973) The persistence and movement of Picloram and 

2,4,5-T in soils. Journal of Environ- mental Quality 2(4):485-488. (Also~In~unpublished 

study re- ceived May 5, 1975 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:221997-T) 

59414 Scifres, C.J.; Burnside, O.C.; McCarty, M.K. (1969) Movement and persistence of 

Picloram in pasture soils of Nebraska. Weed Science 17(4):486-488. (Also~In~unpublished 

submission re- ceived Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:120353-E) 

59962 Uprichard, S.D.; Gilchrist, A.J. (1975) The Influence of Soil Types on the Persistence and 

Leaching of Dowco 290. (Unpublished study received Nov 12, 1980 under 464-563; 

prepared by Dow Chem- ical Europe, S.A., England, submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:099727-D) 

102567 Youngson, C.; Hamaker, J.; Goring, C. (1964) Sorption, Leaching, and Decomposition of 

4-Amino-3,5,6-trichloropicolinic Acid in Soils. (Unpublished study received Jun 19, 1964 

under 464-306; submitted by Dow Chemical U.S.A., Midland, MI; CDL:003500-A) 

109132 Hamaker, J.; Youngson, C.; Goring, C. (1967) Prediction of the Persistence and Activity of 

Tordon Herbicide in Soils under Field Conditions. (Unpublished study received Nov 6, 

1967 under 8F0660; submitted by Dow Chemical Co., Indianapolis, IN; CDL: 091157-A) 

111428 Dow Chemical Co. (1969) ?Study: Picloram Residues in Soil & Water|. (Compilation; 

unpublished study received Apr 30, 1970 under 0F0863; CDL:091491-A) 
Page 69 of 111

111431 Herr, D.; Stroube, E.; Ray, D. (1966) The movement and persistence of picloram in soil. 

Weeds 14(3):248-250. (Also In unpublished submission received Apr 4, 1970 under 

0F0863; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-H) 

111434 Bjerke, E.; Getzendaner, M.; Van Giessen, B.; et al. (1969) Resi- dues of Picloram in Soil 

from Treatment of Rangeland with Tor- don Herbicide: Report GH-C 311. (Unpublished 

study received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., Indi- anapolis, 

IN; CDL:091492-N) 

111435 Dow Chemical Co. (1969) ?Picloram: Residues in Soil|. (Compila- tion; unpublished study 

received Apr 4, 1970 under 0F0863; CDL: 091492-O) 

111436 Merkle, M.; Baur, J.; Bovey, R.; et al. (1968) The fate of herbi- cides used to control brush. 

Pages 53-56, In Brush Research in Texas. By ?. ?S.l.: s.n.|. (PR-2601; also In unpublished 

submission received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., 

Indianapolis, IN; CDL:091492-P) 

111437 Sheets, T. (1968) Letter sent to J. Davidson dated Oct 9, 1968 ?Picloram: Soil persistence 

data|. (Unpublished study received Apr 4, 1970 under 0F0863; prepared by North Carolina 

State Univ., Dept. of Entomology, Pesticide Residue Research Labora- tory, submitted by 

Dow Chemical Co., Indianapolis, IN; CDL: 091492-Q) 

111438 Ogg, A.; Wapensky, L. (1969) Measurement of Picloram Persistence in Two Western U.S. 

Soils. (Abstract 225; U.S. Agricultural Research Service, Pesticide Regulation Div.; 

unpublished study; CDL:091492-R) 

111439 Scifres, C.; Burnside, O.; McCarty, M. (1968?) Movement and Per- sistence of Picloram in 

Pasture Soils of Nebraska. Summary of studies 091492-G, 091492-H, 091492-K and 

091492-M. (Unpub- lished study received Apr 4, 1970 under 0F0863; prepared by Texas A 

& M Univ., Agricultural Research and Extension Center, Brush Research and others, 

submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-S) 

111440 Keys, C.; Friesen, H. (1968) Persistence of picloram activity in soil. Weed Science 

16(3):341-343. (Also In unpublished sub- mission received Apr 4, 1970 under 0F0863; 

submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-T) 

111444 Cheng, H. (1968) Effects of Soil Properties on the Fate of Piclo- ram in Soils. (Unpublished 

study received Apr 4, 1970 under 0F0863; prepared by Washington State Univ., submitted 

by Dow Chemical Co., Indianapolis, IN; CDL:091492-Z) 

111491 Norris, L. (1969) Herbicides Runoff from Forest Lands Sprayed in Summer. Research 

progress rept. dated Feb 10, 1969. (Unpub- lished study received Sep 26, 1974 under 464-

323; prepared by Western Society of Weed Science, submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:120345-L) 

111493 Norris, L. (1971) Herbicide Residues in Soil and Water from Bonne- ville Power 

Administration Transmission Line Rights-of-way. (U. S. Forest Service; unpublished study; 

CDL:120345-N) 

111494 Norris, L. (1972) Herbicide Residues in Soil, Water, and Vegetation or Spray Interception 

Discs, from Bonneville Power Administra- tion Transmission Line Rights-of-way. (U.S. 
Page 70 of 111

Forest Service, Forestry Sciences Laboratory; unpublished study; CDL:120345-O) 

111499 Evans, J.; Duseja, D. (1973) Herbicide Contamination of Surface Runoff Waters. By Utah 

State Univ. Washington, DC: U.S. En- vironmental Protection Agency, Office of 

Researching and Mon- itoring. (EPA-R2-73-266; available from Superintendent of 

Documents, U.S. Government Printing Office, Washington, DC 20402; published study; 

CDL:120352-C) 

111533 Goring, C.; Youngson, C.; Hamaker, J. (1965) Tordon herbicide ... disappearance from 

soils. Down to Earth 20(4):3-5. (Unpub- lished study received 1965 under unknown admin. 

no.; submitted by Dow Chemical U.S.A., Midland, MI; CDL:122992-A) 

112013 Baur, J.; Baker, R.; Bovey, R.; et al. (1972) Concentration of picloram in the soil profile. 

Weed Science 20(4):305-309. (Also In unpublished submission received Sep 26, 1974 

under 464- 323; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 120318-E) 

128714 Dow Chemical U.S.A. (1983) Residue Chemistry: ?Tordon K Salt Liq- uor: Grains and 

Animal Tissue|. (Compilation; unpublished study received Jun 20, 1983 under 464-502; 

CDL:250508-A; 250509) 

128951 Bjerke, E.; Ervick, D. (1976) Residues of Picloram in Soil follow- ing Application of 

Tordon 101 Mixture to Plots in California: Laboratory Report Code: GH-C 946. 

(Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:250517-E) 

128952 Bjerke, E.; Ervick, D. (1976) Residues of Picloram in Soil from Agricultural Plots Treated 

with Tordon 22K Herbicide for Peren- nial Weed Control: Laboratory Report Code: GH-C 

903. (Unpub- lished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-F) 

128954 Bovey, R.; Dowler, C. (1967) Herbicide Residues in Soil--Experiment 12: Document No. 

42365. 1966 Annual rept. (Unpublished study received Jun 16, 1983 under 464-502; 

prepared by U.S. Agricul- tural Research Service and Texas A & M Univ., submitted by 

Dow Chemical U.S.A., Midland, MI; CDL:250517-H) 

128963 Fryer, D.; Smith, P.; Ludwig, J. (1979) Long-term persistence of Picloram in a sandy loam 

soil. J. Environ. Qual. 8(1):83-86. (Also In unpublished submission received Jun 16, 1983 

under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 250517-R) 

128978 McNeal, H.; Erickson, L. (1969) Persistance ?sic| of Five Herbi- cides in Koester Silt Loam 

Soil. (Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250518-C) 

128982 Perez, R. (1980) Residues of Picloram in Soil following Application of Tordon Beads 

Herbicide: Laboratory Report Code GH-C 1310. Final rept. (Unpublished study received 

Jun 16, 1983 under 464- 502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

250518-G) 

128994 Youngson, C. (1964) Distribution of Tordon in Soil Profiles from Second Sampling of the 

Hays, Kansas Experiment: Report No. GS- 673. Final rept. (Unpublished study received 

Jun 16, 1983 un- der 464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 
Page 71 of 111

250518-T) 

128995 Goring, C.; Youngson, C. (1966) Residues of Tordon in Soil from Field Experiments

Treated with Tordon and Sampled at Various In- tervals after Treatment: Report No. GS771. (Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250518-U) 

128998 Zimdahl, R. (1975) Column Leaching Studies with Triclopyr and Pi- cloram: A Report. 

(Unpublished study received Jun 16, 1983 un- der 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL: 250518-X) 

136477 Hamaker, J.; Johnston, H.; Martin, R.; et al. (1963) A picolinic acid derivative: A plant 

growth regulator. Science 141(Jul 26): 363. (Also In unpublished submission received Jun 

26, 1966 un- der unknown admin. no.; submitted by Dow Chemical U.S.A., Mid- land, MI; 

CDL:003384-B) 

140315 Byers, G.E. (1971) The Movement of Two Herbicides in Three Soils. Master's thesis, North 

Carolina State Univ., Dept. of Soil Sci- ence. (Unpublished study received Mar 9, 1977 

under 464-423; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:228627-K) 

140317 Dowler, C.C.; Forestier, W.; Tschirley, F.H. (1967) Effect and persistence of herbicides 

applied to soil in Puerto Rican for- ests. Weed Science 16:45-50. (Also~In~unpublished 

submission received Mar 9, 1977 under 464-423; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:228627-N) 

140320 Goring, C.A.I.; Youngson, C.R.; Hamaker, J.W. (1965) Tordon herbi- cide--disappearance 

from soils. Down to Earth 20(4):4-5. (In- complete; also~In~unpublished submission 

received Mar 9, 1977 under 464-423; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:228627-R) 

145960 Interregional Research Project No. 4 (1975?) The Results of Tests on the Amount of 

Picloram Residues Remaining in or on Sugarcane Including a Description of the Analytical 

Method Used. Unpub- lished compilation. 186 p. 

160126 Oliver, G.; Bjerke, E.; Gantz, R. (1986) Field Dissipation and Leaching Study for Grazon 

P+L Herbicide: GH-C 1819. Unpub- lished study prepared by Dow Chemical USA. 55 p. is 

Grazon= Clopyralid?

400598

01

Oliver, G.; Bjerke, E. (1987) Update on Field Leaching Study for Grazon P+L Herbicide: 

[Supplement to Mrid 160126]. Unpublished study prepared by Dow Chemical U.S.A., 

Agricultural Products Dept. 8 p. 

416469

01

Cleveland, C.; Bjerke, E.; Oliver, G. (1990) A Field Dissipation Study of Picloram 

Conducted in Bremond, Texas: Lab Project Num- ber: GH-C 2402: Protocol No. 87057. 

Unpublished study prepared by DowElanco in cooperation with Craven Laboratories, 

National Environmental Testing Midwest, Inc. and A&L Great Lakes Labs. 163 p. 

425790

01

Petty, D.; Fontaine, D.; Harnick, B. (1992) Non-crop and Right-of-Way Terrestrial 

Dissipation Study of Picloram in North Carolina: Lab Project Number: 90094. Unpublished 

study prepared by DowElanco. 102 p. 
Page 72 of 111

425790

02

Buttler, I.; Roberts, D.; Siders, L.; et al. (1992) Non-crop Right-of-way Terrestrial 

Dissipation of Picloram in California: Lab Project Number: ENV91020. Unpublished study 

prepared by DowElanco. 138 p. 

Gillespie 1975. Residues in Soil- West Va. From Pellet usage EUP

425353

02

Repeate

d in GW 

as well 

Cryer, S.A., J.R. Peterson, C.A. Lacey and G. Kennett (1992) Picloram Fate in the Northen 

Rangeland Ecosystem. Performing Labor, DowElanco North American Environmental 

Chemistry Laboratory Midland, MI48641-1706. A&L Great Lakes Laboratories, Inc. 3503 

Conestoga Drive, Fort Wayne, IN 46808-4413. A&L Midwest Laboratories, Inc. 13611 in 

Bin St. Omaha, NE 68144. Lab Study ID ENV88088. November 26, 1992.

425583

02

Cryer, Steven A. (1992) Supplement to Picloram Fate in the Northern Rangeland 

Ecosystem. Submitting Laboratory DowElanco North American Environmental Chemistry 

laboratory Midland, Michigan 48641-1706. Lab Study ID 88088.

164-2 Aquatic field dissipation

MRID Citation Reference

44008 or 

69074

Davis, E.A.; Ingebo, P.A. (1973) Picloram movement from a chaparral watershed. Water 

Resources Research 9(5):1304-1313; Taken from: ?Without Title| ? (? ):69 (Abstract no. 

74-0312). (Also~In~un- published submission received May 5, 1975 under 464-323; 

submit- ted by Dow Chemical U.S.A., Midland, Mich.; CDL:221997-I) 

108136 Evans, J.; Duseja, D. (1973) Herbicide Contamination of Surface Runoff Waters. By 

Utah State Univ. for U.S. Environmental Pro- tection Agency, Office of Research and 

Monitoring. ?S.l.: s.n.|. (EPA-R2-73-266; available from: Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402; published study; 

CDL:095793-F) 

111413 Youngson, C.; Goring, C. (1967) Movement of Tordon Herbicide in Runoff Water from 

Watersheds. (Unpublished study received Nov 6, 1967 under 8F0660; submitted by Dow 

Chemical Co., Indian- apolis, IN; CDL:091158-B) 

111521

111520= 

1969

Johnsen, T.; Warden, R.; Bean, J.; et al. (1970) Dilution of Picloram Added to Stream 

Water. Progress rept., 1970. (Unpub- lished study received Sep 26, 1974 under 464-323; 

prepared in cooperation with U.S. Agricultural Research Service, submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:120317-L) 

111523 Johnsen, T. (1970) Bumblebee Helicopter Applications of Picloram for Residues 

Studies. Annual rept., 1970. (U.S. Agricultural Research Service, unpublished study; 

CDL:120317-N) 

111525 Johnsen, T. (1970) Residue of Picloram Applied to Utah Juniper, Watershed 3. (U.S. 

Agricultural Research Service, unpublished study; CDL:120317-P) 

128955 Bovey, R.; Richardson, C.; Burnett, E.; et al. (1978) Loss of spray and pelleted Picloram 

in surface runoff water. J. Environ. Qual. 7(2):178-180. (Also In unpublished submission 

received Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, 
Page 73 of 111

MI; CDL:250517-I) 

128957 Byrd, B.; Schwartzbeck, R. (1968) Observations on the Possible Movement of Tordon 

Herbicide in Response to Soil or Water Move- ment: Report GH-P 515. (Unpublished 

study received Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250517-K) 

128958 Byrd, B.; Williams, C.; Bjerke, E. (1970) A Study of Potential Movement of Picloram 

after Application to Highway and Railroad Rights-of-way. (Unpublished study received 

Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

250517-C) 

128961 Dennis, D.; Gillespie, W.; Maxey, R.; et al. (1977) Accumulation and persistence of 

Picloram (Tordon 10K) in surface water and bottom sediments in West Virginia. 

Archives of Environmental Contamination and Toxicology 6:421-433. (Also In 

unpublished submission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-O) 

128989 Williams, R. (1963) Persistence of Tordon in Water: Report No. TA- 239. (Unpublished 

study received Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250518-O) 

164-3 Forest field dissipation

MRID Citation Reference

128956 Brady, H. (1973) Picloram and Dicamba Persistence in Forest Environments. 

(Unpublished study received Jun 16, 1983 under 464- 502; prepared by U.S. Forest 

Service, submitted by Dow Chemical U.S.A., Midland, MI; CDL:250517-J) 

40182201 Neary, D.; Douglass, J.; Fox, W. (1984) Water Quality and Nutrient Cycling 

Impacts of Using the Herbicide Tordon 10K in Preparing Scrub Hardwood for 

Conversion to White Pine (Pinus strobus L.): Final Report. By US Forest Service, 

Southeastern Forest Experi- ment Station, Coweeta Hydrologic Laboratory and 

Univ. of Flori- da: FS-SE-1651-24(1); available from U.S. Government Printing 

Office. 100 p. 

41395301 Knuteson, J.A., K.D. Racke, K.B. Woodburn, E.L. Bjerke and D.G. Petty (1990) 

Picloram Fate in a Coastal Plain Forest Ecosystem. Performing Laboratory, 

DowElanco, Formulations and Environmental Chemistry Midland, Michigan, 

RCRA Analytical Services, Inc. 183 Paradise Blvd. Suite 108 Athens, Georgia, 

A&L Great Lakes Laboratories, Inc. 3505 Conestoga Drive Fort Wayne, Indiana, 

A&L Midwest Laboratories, Inc. 13611 “B” St. Omaha, Nebraska. Laboratory 

Project ID GH-C2299. MRID No. 41395301 February 15, 1990.

42579003 Cryer, S.; Cooley, T.; Schuster, L. (1992) The Dissipation and Movement of 

Picloram in Northern USA Forest Ecosystem: Lab Project Number: ENV91088: 

PM91-2501. Unpublished study prepared by Pan-Agricultural Labs, Inc. 376 p. 

164-5 Long term soil dissipation
Page 74 of 111

MRID Citation Reference

159285 Hamaker, J.; Youngson, C.; Goring, C. (1967) Prediction of the persistence and 

activity of Tordon herbicide in soils under field conditions. Down to Earth 23(2):30-

36. 

401822

01

repeated

Neary, D.; Douglass, J.; Fox, W. (1984) Water Quality and Nutrient Cycling Impacts 

of Using the Herbicide Tordon 10K in Preparing Scrub Hardwood for Conversion to 

White Pine (Pinus strobus L.): Final Report. By US Forest Service, Southeastern 

Forest Experi- ment Station, Coweeta Hydrologic Laboratory and Univ. of Flori- da: 

FS-SE-1651-24(1); available from U.S. Government Printing Office. 100 p. 

165-0 Accumulation Studies -- General

MRID Citation Reference

128986 Scifres, C.; McCall, H.; Maxey, R.; et al. (1977) Residual proper- ties of 2,4,5-T and 

picloram in sandy rangeland soils. J. Envi- ron. Qual. 6(1):36-42. (Also In unpublished 

submission received Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250518-K) 

128996 Youngson, C.; Meikle, R. (1972) Residues of Picloram Acquired by a Mosquito Fish, ..., 

from Treated Water: Problem No. 4221300001. (Unpublished study received Jun 16, 

1983 under 464-502; submit- ted by Dow Chemical U.S.A., Midland, MI; CDL:250518-

V) 

165-5 Bioacculmulation in Fish

421211

08

Woodburn, K.B., S.C. Hansen, T. Ball and P.C. Wilga (1991) Picloram 2-

ethylhexyl ester. Bioconcentration in Rainbow Trout, Oncorhynchus mykiss. 

Performed by The Environmental Toxicology & Chemistry Research 

Laboratory Health and Environmental Sciences. The Dow Chemical Company 

Midland, Michigan 48674. Laboratory Project Study ID ES-DR-0044-1725-1.

128947 Bidlack, H. (1980) Determination of the Bioconcentration Factor for Picloram 

in Bluegill Sunfish during Continuous Aqueous Exposure: GH-C 1384. 

(Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL: 250517-A) 

165-1 Confined rotational crop

MRID Citation Reference

157172 Stafford, L.; Miller, J. (1986) [Carbon-14] Picloram Rotational Crop Study: GH-C 

1784. Unpublished study prepared by Dow Chemical USA. 43 p. 

426418

01

Kimmel, E.; Aldcroft, K.; Ewing, A. (1993) A Confined Rotational Crop Study with 

(carbon 14)-Picloram Using Turnips, Mustard Greens, Wheat, and Corn: Lab Project 

Number: 311W: MET9106. Unpublished study prepared by PTRL-West, Inc. 257 p. 
Page 75 of 111

165-2 Field rotational crop

MRID Citation Reference

157172 Stafford, L.; Miller, J. (1986) [Carbon-14] Picloram Rotational Crop Study: GH-C 

1784. Unpublished study prepared by Dow Chemical USA. 43 p. 

166-1 Ground water-small prospective

MRID Citation Reference

454007

01

Havens, P.; Murrow, D.; Pottinger, M. (2001) State Groundwater Surveillance 

Monitoring Program for Picloram Herbicide: Field Progress Report: Lab Project Number: 

980054: 96-330: ENV960714. Unpublished study prepared by Stone Environmental, Inc. 

and Agvise Laboratories. 861 p. 

No 

MRID

Loss of Picloram i k t o Surface and Ground water. G. 0. Hoffman,

2. D. Robison an6 M. G. Merkle, Texas A & M U n i v e r s i t y , College

Station, Texas.

No 

MRID

D17422

1

Title: Prospective Groundwater Study: Picloram in a Northern Rangeland Environment

425353

02 See above

425353

02

Repeate

d 

Cryer, S.A., J.R. Peterson, C.A. Lacey and G. Kennett (1992) Picloram Fate in the 

Northen Rangeland Ecosystem. Performing Labor, DowElanco North American 

Environmental Chemistry Laboratory Midland, MI48641-1706. A&L Great Lakes 

Laboratories, Inc. 3503 Conestoga Drive, Fort Wayne, IN 46808-4413. A&L Midwest 

Laboratories, Inc. 13611 in Bin St. Omaha, NE 68144. Lab Study ID ENV88088. 

November 26, 1992.

425583

02

Cryer, Steven A. (1992) Supplement to Picloram Fate in the Northern Rangeland 

Ecosystem. Submitting Laboratory DowElanco North American Environmental 

Chemistry laboratory Midland, Michigan 48641-1706. Lab Study ID 88088.

202-1 Drift field evaluation

MRID Citation Reference

403465

07

Johnson, B.; Wright, W. (1978) Evaluation of Nalco-Trol Thickening Agent To Control 

Drift from Aerial Application of Tordon 101 Mixture and Garlon 3A Herbicide. 

Unpublished study prepared by Dow Chemical. 46 p. 

403465

10

Byass, J.; Lake, J. (1977) Spray drift from a tractor-powered field sprayer. Pesticide 

Science 8:117-126. 
Page 76 of 111

403465

11

Stephenson, G. (1976) Evaluation of Nalco-Trol/Lo-Drift and Bivert TDN for Reducing 

Herbicidal Drift in Roadside Spraying. Unpub- lished study prepared by Univ. of Guelph. 

9 p. 

403465

14

Holt, H.; Voeller, J.; Young, J.; et al. (1975) Drift of Tordon 155 mixture in a dormant 

season mist blower application. Industrial Vegetation Management 7(2):19-24. 

403465

18

Lehman, S. (1967) Rrogress (sic) Report of Studies on Effectiveness of Picloram for 

Yaupon and Winged Elm Control: and Characteristics of Norbak Particulated Sprays. 

Unpublished study prepared by Texas A & M Univ. 81 p. 

Non Guideline Selection

24011 Kearney, P.C.; Helling, C.S. (1969) Reactions of pesticides in soils. Residue Reviews 

25:25-44. (Also~In~unpublished submis- sion received Aug 28, 1975 under 100-437; 

submitted by Ciba- Geigy Corp., Greensboro, N.C.; CDL:221042-K) 

26338 Van Schreven, D.A.; Lindenbergh, D.J.; Koridon, A. (1970) Effect of several herbicides on 

bacterial populations and activity and the persistence of these herbicides in soil. Plant and 

Soil 33(? ): 513-532. (Also~In~unpublished submission received Jan 2, 1980 under 2217-

485; submitted by PBI-Gordon Corp., Kansas City, Kans.; CDL:241579-T) 

40673 Sheets, T.J. (1970) Persistence of Triazine herbicides in soils. Residue Reviews 32(? ):287-

310. (Also~In~unpublished submission received Jul 19, 1978 under 201-403; submitted by 

Shell Chemical Co., Washington, D.C.; CDL:234476-N) 

44005 Bovey, R.W.; Scifres, C.J. (1971) Residual Characteristics of Pic- loram in Grassland 

Ecosystems. College Station, Tex.: Texas A & M Univ., Agricultural Experiment Station. 

(B-1111; also~In~ unpublished submission received May 5, 1975 under 464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:221997-E) 

45403 Bovey, R.W.; Scifres, C.J. (1971) Residual Characteristics of Pic- loram in Grassland 

Ecosystems. College Station, Tex.: Texas A & M Univ., Agricultural Experiment Station. 

(B-1111; also~In~ unpublished submission received on unknown date under 0F0863; 

submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:093160-A) 

44022 Norris, L.A.; Moore, D.G. (1970) The entry and fate of forest chem- icals in streams. Pages 

138-158,~In~Proceedings of a Symposium: Forest Land Uses and Stream Environment; 

Oct 19-21, 1970. Cor- vallis, Oreg.: Oregon State Univ., Forestry Extension. (Also 

?~In~unpublished submission received May 5, 1975 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:221997-Y) 

44023 Youngson, C.R.; Gantz, G.L.; Gantz, R.L.; et al. (1966) Residues of Tordon in Soil from 

Fields Treated for Selective Weed Control with Tordon^(R)I Herbicide. Includes undated 

method entitled: Bioassay method for the determination of residues of Tordon her- bicide in 

soil. (Unpublished study received May 5, 1975 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL: 221997-Z) 

44024 Youngson, C.R.; Watson, A.J.; Bovey, R.W.; et al. (1966) Residues of Tordon from Field 
Page 77 of 111

Soils Receiving Multiple Applications. In- cludes undated method entitled: Bioassay 

method for the deter- mination of residues of Tordon herbicide in soil. (Unpublished study 

received May 5, 1975 under 464-323; submitted by Dow Chem- ical U.S.A., Midland, 

Mich.; CDL:221997-AA) 

44025 Youngson, C.R.; Wright, W.G.; Higgins, R.E.; et al. (1966) Residues of Tordon in Soil 

from Fields Treated with Tordon Herbicide for Weed Control. Includes undated method 

entitled: Bioassay method for the determination of residues of Tordon herbicide in soil. 

(Unpublished study received May 5, 1975 under 464-323; submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:221997-AB) 

45366 Bjerke, E.L. (1973) Determination of Residues of Picloram in Soil by Gas 

Chromatography. Method ACR 73.3 dated May 21, 1973. (Unpublished study received Jul 

3, 1975 under 6F1653; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094500-

D) 

69076 Dow Chemical U.S.A. (1975) Summary of the Pathways of the Degra- dation of Picloram. 

(Unpublished study received Mar 9, 1977 under 464-541; CDL:228626-C) 

69077 Dow Chemical Company (1968) Report of an Investigation by Dow of the Alleged 

Presence of Herbicidal Contamination of Irrigation Well Water at Kimball, Nebraska. 

(Unpublished study, including letter dated Jan 24, 1969 from G.E. Lynn to Harry B. Hays, 

received Mar 9, 1977 under 464-541; CDL:228626-D) 

69078 Dow Chemical Company (1968) Determination of 4-Amino-3,5,6-tri- chloropicolinic Acid 

in Water: Method ACR 68 14 dated Sep 26, 1968. (Unpublished study received Mar 9, 

1977 under 464-541; CDL:228626-E) 

69079 U.S. Environmental Protection Agency (1976) Herbicide Contamina- tion in Water 

Supplies, Kimball, Nebraska. (Office of Enforce- ment, National Enforcement 

Investigations Center, and Region VII; unpublished study; CDL:228626-F) 

69973 Dow Chemical Company (1964) Determination of Tordon Residues in Water and Blood by 

Gas Chromatography. Tentative residue de- termination method ACR 64.6 dated Nov 18, 

1964. (Unpublished study received on unknown date under unknown admin. no.; CDL: 

130992-J) 

111412 Dow Chemical Co. (1967) ?Photodecomposition of Tordon and Movement in Run-off 

Water|. (Compilation; unpublished study received Nov 6, 1967 under 8F0660; 

CDL:091158-A) 

111421 Goring, C.; Griffith, J.; O'Melia, F.; et al. (1967) The effect of tordon on microorganisms 

and soil biological processes. Down to Earth 22(4):14-17. (Also In unpublished submission 

received Nov 6, 1967 under 8F0660; submitted by Dow Chemical Co., Indian- apolis, IN; 

CDL:091156-C) 

111500 Goring, C.; Hamaker, J. (1971) The degradation and movement of picloram in soil and 

water. Down to Earth 27(1):12-15. (Also In unpublished study received Sep 26, 1974 under 

464-323; sub- mitted by Dow Chemical U.S.A., Midland, MI; CDL:120352-D) 

111426 Grover, R. (1967) Studies on the degradation of 4-amino-3,5,6- trichloropicolinic acid in 
Page 78 of 111

soil. Weed Res. 7:61-67. (Also In unpublished submission received Nov 6, 1967 under 

8F0660; sub- mitted by Dow Chemical Co., Indianapolis, IN; CDL:091156-K) 

111430 Hamaker, J.; Youngson, C.; Goring, C. (1967) Prediction of the Persistence and activity of 

Tordon herbicide in soils under field conditions. Down to Earth 23(2):30-36. (Also In 

unpub- lished submission received Apr 4, 1970 under 0F0863; submitted by Dow Chemical 

Co., Washington, DC; CDL:091492-G) 

111443 Helling, C. (1968) Pesticide Mobility Investigations Using Soil Thin-layer 

Chromatography. (U.S. Agricultural Research Service; unpublished study; CDL:091492-Y) 

111449 Youngson, C.; Yeaman, M.; Meikle, R. (1969) An Evaluation of Some Factors Influencing 

the Decomposition of ... ?Tordon| in Soil: Report GS-1002. (Unpublished study received 

Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., Indianapolis, IN; CDL: 

091492-AF) 

111450 Youngson, C.; Laskowski, D. (1969) An Evaluation of Various Soil Conditions on the 

Decomposition of ... ?Tordon|: Report GS-1018. Summary of studies 091492-V, 091492-X, 

091492-AB and 091492-AF. (Unpublished study received Apr 4, 1982 under 0F0863; 

submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-AH) 

124630 Debona, A.; Audus, L. (1970) Studies on the effects of herbicides on soil nitrification. 

Weed Res. 10:250-263. (Also In unpub- lished submission received Dec 1, 1970 under 

1F1105; submitted by Agchem Div., Pennwalt Corp., Philadelphia, PA; CDL:094511-K) 

128948 Bidlack, H. (1980) Kinetics of Aged Picloram in a Model Aquatic Microcosm: GH-C 1370. 

(Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:250517-B) 

128962 Frank, R.; Sirons, G.; Ripley, B. (1979) Water: Herbicide con- tamination and 

decontamination of well waters in Ontario, Cana- da, 1969-78. Pesticides Monitoring 

Journal 13(3):120-127. (Also In unpublished submission received Jun 16, 1983 under 464-

502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 250517-Q) 

140318 Dubey, H.D. (1969) Effect of picloram, diuron, ametryne, and prometryne on nitrification 

in some tropical soils. Soil Sci- ence Society of America Proceedings 33:893-896. 

(Also~In~un- published submission received Mar 9, 1977 under 464-423; submit- ted by 

Dow Chemical U.S.A., Midland, Mich.; CDL:228627-O) 

N/A Fate Oneliner Report 1991

Statewide Monitoring of Picloram in West Va. 1984

Product Chemistry Summary

Residue Chemistry Summary

005102 Picloram TIPA Salt Effects Bibliography

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference
Page 79 of 111

27381 Kenaga, E.E. (1969) Tordon herbicides--Evaluation of safety to fish and birds. Down to 

Earth 25(1):5-9. (Also~In~unpublished sub- mission received Jan 8, 1973 under 464-

205; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:008203-G) also in 

005101 and 005104

71-2 Avian Dietary Toxicity

MRID Citation Reference

129069 Fink, R. (1975) Eight-day Dietary LC50--Bobwhite Quail: Tordon 101 Mixture: Project 

No. 103-133. Final rept. (Unpublished study received Jun 24, 1983 under 464-502; 

prepared by Truslow Farms, Inc., submitted by Dow Chemical U.S.A., Midland, MI; 

CDL: 250605-H) 

129071 Fink, R. (1975) Eight-day Dietary LC50--Mallard Ducks: Tordon 101 Mixture: Project 

No. 103-134. Final rept. (Unpublished study received Jun 24, 1983 under 464-502; 

prepared by Truslow Farms, Inc., submitted by Dow Chemical U.S.A., Midland, MI; 

CDL: 250605-J) 

71-4 Avian Reproductive Effects

129082 

or 

129081

Somers, J.; Moran, E.; Reinhart, B. (1974) Effect of external application of pesticides to 

the fertile egg on hatching success and early chick performance. 2. Commercial-herbicide 

mixtures of 2,4-D with picloram or 2,4,5-T using the pheasant. Bulletin of Environmental 

Contamination & Toxicology 11(4):339-342. (Also In unpublished submission received 

Jun 24, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250605-V) 

141980 Somers, J.; Moran, E.; Reinhart, B. (1978) Reproductive success of hens and cockerels 

originating from eggs sprayed with 2,4-D, 2, 4-5-T and picloram followed by early 

performance of their progeny after a comparable in ovo exposure. Bull. Environm. 

Contam. Toxicol. 20:111-119.

72-1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

129065 Dill, D.; Mayes, M. (1982) The Toxicity of Picloram ..., Triisopropanolamine Salt, to 

Representative Freshwater Organisms: Labora- tory Report Code ES-562. Final rept. 

(Unpublished study re- ceived Jun 24, 1983 under 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:250605-D) 

129075 

or 

4520510

7

Lorz, H.; Glenn, S.; Williams, R.; et al. (1979) Effects of Selected Herbicides on 

Smolting of Coho Salmon. By Oregon, Dept. of Fish and Wildlife, Research and 

Development Section and U.S. Forest Service, Pacific Northwest Forest and Range 

Experiment Station. Corvallis, OR: US EPA. (EPA-600/3-79-071; Grant #R- 804283; 

pages i,iv-x,1,6-14,40-50,83-85,92 only; also In unpublished submission received Jun 

24, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; 
Page 80 of 111

CDL:250605-N) 

41478 or 

75783

Hardy, J.L. (1962) Toxicity of Tordon^(R)I and Formulations to Aquatic Organisms. 

(Unpublished study received Nov 6, 1967 un- der 0F0863; submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:094524-K) 

41479 Hardy, J.L. (1963) Toxicity Studies with Tordon 101 Mixture on Fish, Snails and 

Daphnia. (Unpublished study received Nov 6, 1967 under 0F0863; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:094524-L) 

41146 Duddles, G.A. (1968) The Acute Toxicity of Tordon Herbicide Formulations: 144, 155, 

202, 212 and 225. (Unpublished study re- ceived on unknown date under 8F0660; 

submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094930-H)

41147 Duddles, G.A. (1968) The Acute Fish Toxicity of the Triisopropanol- amine salt of 4-

Amino-3,5,6-trichloropicolinic acid. (Unpub- lished study received on unknown date 

under 8F0660; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094930-I)

72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference

75783 or 

41478

Hardy, J.L. (1962) Toxicity of Tordon^(R)I and Formulations to Aquatic Organisms. 

(Unpublished study received Nov 21, 1967 un- der 8F0660; submitted by Dow Chemical 

Co., Indianapolis, Ind.; CDL:091155-M) 

129065 Dill, D.; Mayes, M. (1982) The Toxicity of Picloram ..., Triisopro- panolamine Salt, to 

Representative Freshwater Organisms: Labora- tory Report Code ES-562. Final rept. 

(Unpublished study re- ceived Jun 24, 1983 under 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:250605-D) 

41478 Hardy, J.L. (1962) Toxicity of Tordon^(R)I and Formulations to Aquatic Organisms. 

(Unpublished study received Nov 6, 1967 un- der 0F0863; submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:094524-K) 

41479 Hardy, J.L. (1963) Toxicity Studies with Tordon 101 Mixture on Fish, Snails and 

Daphnia. (Unpublished study received Nov 6, 1967 under 0F0863; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:094524-L) 

41483 Dow Chemical Company (1964?) Toxicity to Aquatic Organisms, Other Than Fish: 

Summary Statement. Summary of study 094524-R. (Un- published study received Nov 

6, 1967 under 0F0863; CDL:094524-Q) 

72-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

111552 Bureau of Commercial Fisheries, Biological Laboratory (1968) Bioassay Screening Test: 

(Tordon 22K). (Unpublished study; CDL: 130991-A) 

129074 Heitmuller, T. (1975) Acute Toxicity of Tordon 101 Mixture to Lar- vae of the Eastern 
Page 81 of 111

Oyster (Crassostrea virginica), Pink Shrimp (Penaeus duorarum), and Fiddler Crabs (Uca 

pugilator). (Unpub- lished study received Jun 24, 1983 under 464-502; prepared by 

Bionomics--EG & G, Inc., submitted by Dow Chemical U.S.A., Mid- land, MI; 

CDL:250605-M) 

4395950

3

Boeri, R.; Magazu, J.; Ward, T. (1995) Tordon 101M Herbicide: Acute Toxicity to the 

Silverside, Menidia beryllina: Lab Project Number: DECO-ES-2927: 647-DO. 

Unpublished study prepared by T.R. Wilbury Labs, Inc. 26 p. 

72-4 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study

MRID Citation Reference

27381 Kenaga, E.E. (1969) Tordon herbicides--Evaluation of safety to fish and birds. Down to 

Earth 25(1):5-9. (Also~In~unpublished sub- mission received Jan 8, 1973 under 464-

205; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:008203-G) 

41146 Duddles, G.A. (1968) The Acute Toxicity of Tordon Herbicide For- mulations: 144, 155, 

202, 212 and 225. (Unpublished study re- ceived on unknown date under 8F0660; 

submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094930-H) 

41147 Duddles, G.A. (1968) The Acute Fish Toxicity of the Triisopropanol- amine salt of 4-

Amino-3,5,6-trichloropicolinic acid. (Unpub- lished study received on unknown date 

under 8F0660; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:094930-I) 

41476 Winston, A.W., Jr. (1963) Fish Toxicity of Tordon and Tordon Formu- lations. 2nd rept. 

(Unpublished study received Nov 6, 1967 un- der 0F0863; submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:094524-I) 

41477 Winston, A.W., Jr. (1962) Fish Toxicity of Tordon^(R)I and Tordon Formulations. 1st 

rept. (Unpublished study received Nov 6, 1967 under 0F0863; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:094524-J) 

44103 Dow Chemical Company (1963) Toxicity Studies with Tordon 101 Mix- ture on Fish, 

Snails and Daphnia. (Unpublished study received Apr 1, 1963 under 464-306; 

CDL:100568-F) 

129075

4520510

7

Lorz, H.; Glenn, S.; Williams, R.; et al. (1979) Effects of Selected Herbicides on 

Smolting of Coho Salmon. By Oregon, Dept. of Fish and Wildlife, Research and 

Development Section and U.S. Forest Service, Pacific Northwest Forest and Range 

Experiment Station. Corvallis, OR: US EPA. (EPA-600/3-79-071; Grant #R- 804283; 

pages i,iv-x,1,6-14,40-50,83-85,92 only; also In unpublished submission received Jun 

24, 1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250605-N) 

4395950

4

Weinberg, J.; Hugo, J.; Landre, A. (1996) Evaluation of the Toxicity of Picloram 

Triisopropanolamine (TIPA) Salt to the Early Life-Stages of the Fathead Minnow, 

Pimephales promelas Rafinesque: Lab Project Number: DECO-ES-3037. Unpublished 

study prepared by The Dow Chemical Co. 39 p. 

123-1 Seed germination/seedling emergence and vegitative vigor
Page 82 of 111

MRID Citation Reference

4327660

1

Schwab, D. (1994) Evaluating the Effects of Picloram on the Germination, Emergence, 

and Vegetative Vigor of Non-Target Terrestrial Plants: Final Report: Lab Project 

Number: 41404. Unpublished study prepared by ABC Laboratories, Inc. 137 p. 

155937 Jotcham, J.R. (1985) An Evaluation of Crop Sensitivity to Soil Active Herbicides by 

Laboratory Bioassay Technique. Balsam Research, Berwick, Nova Scotia, April 1985. 

(Unpublished Study Received January 13, 1986, Submitted by Dow Chemical under 

Accession No. 261128).

4129650

1

Weseloh, J.W. and G.D. Stockdale (1989) A Study to Determine the Effects of 

Picloram on Seed Germination, Seedling Emergence and Vegetative Vigor. Laboratory 

Project ID: GH-P 1444. Conducted by Midland Field Research Station, Dow Chemical 

U.S.A., Midland, MI. Submitted by DowElanco, Midland, MI. EPA No.41296501. 

123-2 Aquatic plant growth

MRID Citation Reference

4140770

1

Hughes, J. (1990) The Toxicity of Tordon 101 to Selenastrum capri- cornutum: Lab 

Project Number: 0460-04-1100-4. Unpublished study prepared by Malcolm Pirnie, Inc. 

33 p. 

4140770

2

Hughes, J. (1990) The Toxicity of Picloram, Potassium Salt to Selenastrum 

capricornutum. Laboratory Project ID: 0460-04-1100-2. Conducted by Malcolm Pirnie, 

Inc., Elmsford, NY. Submitted by DowElanco, Indianapolis, IN. EPA MRID No. 

414077-02.

4323030

3

Boeri, R.L., J.P. Magazu and T.J. Ward (1994) Tordon 101 Herbicide: Toxicity to the 

Freshwater Diatom, Navicula pelliculosa. 

Laboratory Project No. 433-DO. Conducted by T.R. Wilbury Laboratories, Inc., 

Marblehead, MA. Submitted by the Dow Chemical Company, Midland, MI. EPA 

MRID No. 43230303.

4323030

6

Ward, T.; Magazu, J.; Boeri, R. (1994) Tordon 101 Herbicide: Toxicity to the Marine 

Diatom, Skeletonema costatum: Lab Project Number: 434/DO: ES/2770. Unpublished 

study prepared by T. R. Wilbury Laboratories, Inc. 25 p. 

4323030

9

Boeri, R.; Magazu, J.; Ward, T. (1994) Tordon 101 Herbicide: Toxicity to the 

Freshwater Blue-Green Alga, Anabaena flos-aquae: Lab Project Number: 435/DO: 

ES/2771. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 24 p. 

4323031

2

Milazzo, D.; Kirk, H.; Humbert, L.; et al. (1994) The Toxicity of Tordon 101 Herbicide 

Formulation to the Aquatic Plant Duckweed, Lemna gibba L.G-3: Lab Project Number: 

DECO-ES-2763. Unpublished study prepared by The Environmental Toxicology & 

Chemistry Research Lab. 35 p. 
Page 83 of 111

Acute Toxicity to Honeybees

129066 Doty, A.E. (1965) Some Observations of theToxicity of TORDON* Herbicide on 

Honey Bees. Bioproducts Department. The Dow Chemical Company. Midland, 

Michigan

111488 Moffett, J.O., H.L. Morton and R.H. Macdonald (1972) Toxicity of Some Herbicidal 

Sprays to Honey Bees. J. Econ. Ent. 65: 32-36

41366901 Hoxter, K.A. and M. Jaber (1989) Tordon® 101: An Acute Contact Toxicity Study 

with the Honey Bee. Laboratory Project No. 103-313. Conducted by Wildlife 

International Ltd., Easton, MD. Submitted by the Dow Chemical Company, Midland, 

MI. EPA MRID No. 41366901.

005102 Picloram TIPA Salt Chemistry Fate Bibliography

163-1 Leach/adsorp/desorption

MRID Citation Reference

00160126 Oliver, G., E. Bjerke and R. Gantz (1986) Field Dissipation and Leaching Study 

for Grazon P+L Herbicide: GH-C 1819. Unpublished Study Prepared by Dow 

Chemical USA.

40059801 Oliver, G. and E. Bjerke (1987) Update on Field Leaching Study for Grazon P+L 

Herbicide: Supplement to MRID 00160126. Unpublished Study Prepared by Dow 

Chemical USA, Agricultural Products Dept.

164-1 Terrestrial field dissipation

MRID Citation Reference

59416 Scifres, C.J.; Hahn, R.R.; Diaz-Colon, J.; et al. (1971) Picloram persistence in 

semiarid rangeland soils and water. Weed Sci- ence 19(4):381-384. 

(Also~In~unpublished submission received Sep 26, 1974 under 464-323; submitted 

by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-G) 

111434 Bjerke, E.; Getzendaner, M.; Van Giessen, B.; et al. (1969) Resi- dues of Picloram 

in Soil from Treatment of Rangeland with Tor- don Herbicide: Report GH-C 311. 

(Unpublished study received Apr 4, 1970 under 0F0863; submitted by Dow 

Chemical Co., Indi- anapolis, IN; CDL:091492-N) 

111472 Green, L. (1972) Letter sent to L. Warren dated Sep 7, 1972 ?Effi- cacy of various 

chemicals applied to watersheds|: 4400. (U.S. Forest Service, Pacific Southwest 

Forest and Range Experiment Station, Forest Fire Laboratory; unpublished study; 

CDL: 120318-S) 

111475 Haas, R.; Scifres, C.; Merkle, M.; et al. (1971) Occurrence and persistence of 

picloram in grassland water sources. Weed Res. 11:54-62. (Also In unpublished 

submission received Sep 26, 1974 under 464-323; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:120318-X) 
Page 84 of 111

111519 Hunter, J.; Stobbe, E. (1972) Movement and persistence of picloram in soil. Weed 

Science 20(5):486-489. (Also In unpublished submission received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120317-J) 

128987 Sirons, G.; Frank, R.; Dell, R. (1977) Picloram residues in sprayed MacdonaldCartier Freeway right-of-way. Bulletin of Environmen- tal Contamination & 

Toxicology 18(5):526-533. (Also In unpub- lished submission received Jun 16, 

1983 under 464-502; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250518-M) 

128988 Suffling, R.; Smith, D.; Sirons, G. (1974) Lateral loss of picloram and 2,4-D from a 

forest podsol during rainstorms. Weed Re- search 14:301-304. (Also In 

unpublished submission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Mid- land, MI; CDL:250518-N) 

130584 Johnsen, T.; Warskow, W. (1980) Effects of fall burning of chapar- ral woodland 

on soil residues of Picloram. Weed Science 28(3): 282-284. (Also In unpublished 

submission received Jun 16, 1983 under 464-502; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:250517AB) 

00160126 Oliver, G., E. Bjerke and R. Gantz (1986) Field Dissipation and Leaching Study for 

Grazon P+L Herbicide: GH-C 1819. Unpublished Study Prepared by Dow 

Chemical USA.

164-2 Aquatic field dissipation

MRID Citation Reference

69080 Wicks, G.A.; Fenster, C.R. (1975) Picloram Movement in Nebraska Ground 

Water Study during 1969 to 1975. (Unpublished study received Mar 9, 1977 under 

464-541; prepared by Univ. of Ne- braska, North Platte Station and Panhandle 

Station, submitted by Dow Chemical Co., Midland, Mich.; CDL:228626-G) 

111475 Haas, R.; Scifres, C.; Merkle, M.; et al. (1971) Occurrence and persistence of 

picloram in grassland water sources. Weed Res. 11:54-62. (Also In unpublished 

submission received Sep 26, 1974 under 464-323; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:120318-X) 

128971 Johnsen, T. (1980) Picloram in water and soil from a semiarid pin- yon-juniper 

watershed. J. Environ. Qual. 9(4):601-605. (Also In unpublished submission 

received Jun 16, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250517AA) 

128972 Johnsen, T.; Warskow, W. (1980) Picloram dissipation in a small southwestern 

stream. Weed Science 28(5):612-615. (Also In un- published submission received 

Jun 16, 1983 under 464-502; sub- mitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250517AC) 

111520= 1969

115521= 1970

Johnson, T.; Warden, R.; Bean, J.; et al. (1969) Dilution of Picloram Added to 

Stream Water. Progress rept., 1969. (Un- published study received Sep 26, 1974 
Page 85 of 111

under 464-323; prepared in cooperation with U.S. Agricultural Research Service, 

Crops Research Div., submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:120317-K) 

Groundwater Monitoring

59422 Wicks, G.A.; Fenster, C.R. (1972) Progress Report of Picloram Movement in a 

Nebraska Ground Water Study (1969-1972). (Unpub- lished study received Sep 26, 

1974 under 464-323; prepared by Univ. of Nebraska, North Platte and Panhandle 

Stations, sub- mitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-M) 

Non- Guideline

111428 Dow Chemical Co. (1969) ?Study: Picloram Residues in Soil & Water|. (Compilation; 

unpublished study received Apr 30, 1970 under 0F0863; CDL:091491-A) 

111550 Byrd, B. (1969) Railroad: ?Efficacy of Tordon 101 plus Norbak|. Interim rept. 

(Unpublished study received Jan 21, 1969 under 464-EX-31; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL: 123616-A) 

128714 Dow Chemical U.S.A. (1983) Residue Chemistry: ?Tordon K Salt Liq- uor: Grains and 

Animal Tissue|. (Compilation; unpublished study received Jun 20, 1983 under 464-502; 

CDL:250508-A; 250509) 

135503 Dow Chemical U.S.A. (1970) Performance: ?Tordon 101 Weed Killer: Residue and 

Environmental Chemistry Data|. (Compilation; unpub- lished study received Jan 19, 

1970 under 464-306; CDL:003508-A) 

005104 Picloram potassium salt Eco Effects Bibliography

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference

27381 Kenaga, E.E. (1969) Tordon herbicides--Evaluation of safety to fish and birds. 

Down to Earth 25(1):5-9. (Also In unpublished submission received Jan 8, 1973 

under 464-205; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:008203-

G) 

157174

164726

Beavers, J. (1985) Picloram Potassium Salt: An Acute Oral Toxicity Study with the 

Mallard: Final Report: Project No. 103-245. Un- published study prepared by 

Wildlife International Ltd. 17 p. 

41106 Stevenson, G.T. (1962) Oral Toxicity of Tordon acid in Chickens. (Unpublished 

study received Nov 6, 1967 under 0F0863; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:094525-Q)
Page 86 of 111

71-2 Avian Dietary Toxicity

MRID Citation Reference

112977 Fink, R. (1975) Eight-day Dietary LC50--Mallard Ducks: Tordon 10K Pellets: 

Project No. 103-130. Final rept. (Unpublished study received Sep 10, 1976 under 

464-541; prepared by Truslow Farms, Inc., submitted by Dow Chemical U.S.A., 

Midland, MI; CDL: 226137-A) 

112978 Fink, R. (1975) Eight-day Dietary LC50--Bobwhite Quail: Tordon 10K Pellets: 

Project No. 103-129. Final rept. (Unpublished study received Sep 10, 1976 under 

464-541; prepared by Truslow Farms, Inc., submitted by Dow Chemical U.S.A., 

Midland, MI; CDL: 226137-B) 

129068 Fink, R. (1975) Eight-day Dietary LC50--Bobwhite Quail: Tordon 22K: Project 

No. 103-131. Final rept. (Unpublished study received Jun 24, 1983 under 464-

502; prepared by Truslow Farms, Inc., submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250605-G) 

129070 Fink, R. (1975) Eight-day Dietary LC50--Mallard Ducks: Tordon 22K: Project 

No. 103-132. Final rept. (Unpublished study received Jun 24, 1983 under 464-

502; prepared by Truslow Farms, Inc., submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250605-I) 

40054501 Beavers, J.?(1986) Picloram Potassium Salt: A Dietary LC50 Study with the 

Bobwhite: Final Report: Wildlife International, Ltd. Project No. 103-244 

(Unpublished Study Submitted by Dow Chemical Company, Received October 1, 

1986 under Accession Nos. 261883, 265983, 40054501.

164727 Beavers, J. (1986) Picloram Potassium Salt: A Dietary LC50 Study with the 

Bobwhite: Final Report: WIL Project No. 103-244. Un- published study prepared 

by Wildlife International Ltd. 17 p. 

41113 Stevenson, G.T. (1965) A Gamebird Toxicology Study--Acute Dietary Feeding 

of Tordon to Wild Type Mallard Ducklings. (Unpublished study received Nov 6, 

1967 under 0F0863; submitted by Dow Chemi- cal U.S.A., Midland, Mich.; 

CDL:094525-X)

71-4 Avian reproduction

141980 Somers, J., E.T. Morgan, Jr. and B.S. Reinhart (1978) Reproductive Success of Hens 

and Cockerels Originating from Eggs Sprayed with 2,4-D, 2,4,5-T and Picloram 

Followed by Early Performance of Their Progeny after a Comparable in ovo

Exposure. Bull. Environ. Contam. Toxicol. 20: 111-119.

72-1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

75784 Williams, R.C.; Gantz, R.L. (1963) Fish Toxicity of Tordon^(R)I. (Unpublished 
Page 87 of 111

study received Nov 21, 1967 under 8F0660; submit- ted by Dow Chemical Co., 

Indianapolis, Ind.; CDL:091155-O) 

75786 Swabey, Y.H. (1963) Letter sent to E.E. Wiffen dated May 8, 1963: ?Toxicity of 

Tordon 22K to lake emerald shiner|: Toxicity Test No. 63-34. (Ontario, Water 

Resources Commission, Div. of Labo- ratories; unpublished study; CDL:091155-

R) 

111461 McCann, J. (1967) ?Tordon 24.9%: Bluegill|: Test No. 48. (U.S. Agricultural 

Research Service, Pesticides Regulation Div.; Animal Biology Laboratory; 

unpublished study; CDL:108529-A) 

129063 Cope, O. (1966) Sport Fishery Research. Denver, CO: USDI. (Quar- terly progress 

reports, Sep 30; also In unpublished submission received Jun 24, 1983 under 464-

502; submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-B) 

129072 Fogels, A.; Sprague, J. (1977) Comparative short-term tolerance of zebrafish, 

flagfish, and rainbow trout to five poisons including potential reference toxicants. 

Water Research 11:811-817. (Al- so In unpublished submission received Jun 24, 

1983 under 464- 502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

250605-K) 

129075 Lorz, H.; Glenn, S.; Williams, R.; et al. (1979) Effects of Selected Herbicides on 

Smolting of Coho Salmon. By Oregon, Dept. of Fish and Wildlife, Research and 

Development Section and U.S. Forest Service, Pacific Northwest Forest and Range 

Experiment Station. Corvallis, OR: US EPA. (EPA-600/3-79-071; Grant #R804283; pages i,iv-x,1,6-14,40-50,83-85,92 only; also In unpublished submission 

received Jun 24, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250605-N) 

129080 Sergeant, M.; Blazek, D.; Elder, J.; et al. (1971) The toxicity of 2,4-D and picloram 

herbicides to fish. Proc. Indiana Academy of Science 80:114-123. (Also In 

unpublished submission received Jun 24, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250605-T) 

43959503 Boeri, R.L., J.P. Magazu and T.J. Ward (1995) Tordon 101M Herbicide: Acute 

Toxicity to the Silverside, Menidia beryllina Laboratory: T.R. Wilbury 

Laboratories, Inc., Marblehead, MA. Sponsor: DowElanco, Midland, MI. ID 647-

DO.

95013 Alexander, H.C. and T.L. Batchelder (1966) Acute Fish Toxicity of Daxtron® , 

Tordon® and Dursban® to Three Species of Fish. Waste Control Department. The 

Dow Chemical Company. Midland, Michigan.

72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference

75783 Hardy, J.L. (1962) Toxicity of Tordon^(R)I and Formulations to Aquatic Organisms. 

(Unpublished study received Nov 21, 1967 un- der 8F0660; submitted by Dow 
Page 88 of 111

Chemical Co., Indianapolis, Ind.; CDL:091155-M) 

129077 McCarty, W. (1977) Toxicity of Potassium Salt of Picloram to Daph- nids. 

(Unpublished study received Jun 24, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250605-P) 

151783 Gersich, F.M., D.L. Hopkins and D.P. Milazzo (1984) The Acute and Chronic 

Toxicity of Technical Picloram to Daphnia magna straus. Prepared by Dow Chemical, 

Midland, MI.

72-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

111560 Heitmuller, T. (1975) Acute Toxicity of Tordon 10K Pellets to Larvae of the Easter 

Oyster ..., Pink Shrimp ..., and Fiddler Crabs (Uca-pugilater). (Unpublished study 

received Sep 10, 1976 under 464-541; prepared by Bionomics--EG & G, Inc., 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:226137-D) 

129073 Heitmuller, T. (1975) Acute Toxicity of Tordon 22K to Larvae of the Eastern Oyster 

(Crassostrea virginica), Pink Shrimp (Penaeus du- orarum), and Fiddler Crabs (Uca 

pugilator). (Unpublished study received Jun 24, 1983 under 464-502; prepared by 

Bionomics-- EG & G, Inc., submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250605-L) 

43959502 Boeri, R.; Magazu, J.; Ward, T. (1995) Tordon 22K Herbicide: Acute Toxicity to 

the Sheepshead Minnow, Cyprinodon variegatus: Lab Project Number: DECO-ES2928: 651-DO. Unpublished study prepared by T.R. Wilbury Labs, Inc. 25 p. 

72-4 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study

MRID Citation Reference

27381 Kenaga, E.E. (1969) Tordon herbicides--Evaluation of safety to fish and birds. 

Down to Earth 25(1):5-9. (Also~In~unpublished sub- mission received Jan 8, 1973 

under 464-205; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:008203-

G) 

41476 Winston, A.W., Jr. (1963) Fish Toxicity of Tordon and Tordon Formu- lations. 2nd 

rept. (Unpublished study received Nov 6, 1967 un- der 0F0863; submitted by Dow 

Chemical U.S.A., Midland, Mich.; CDL:094524-I) 

41477 Winston, A.W., Jr. (1962) Fish Toxicity of Tordon^(R)I and Tordon Formulations. 

1st rept. (Unpublished study received Nov 6, 1967 under 0F0863; submitted by 

Dow Chemical U.S.A., Midland, Mich.; CDL:094524-J) 

41480 Williams, R.C.; Gantz, R.L. (1963) Fish Toxicity of Tordon^(R)I. (Unpublished 

study received Nov 6, 1967 under 0F0863; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:094524-M) 
Page 89 of 111

129075 Lorz, H.; Glenn, S.; Williams, R.; et al. (1979) Effects of Selected Herbicides on 

Smolting of Coho Salmon. By Oregon, Dept. of Fish and Wildlife, Research and 

Development Section and U.S. Forest Service, Pacific Northwest Forest and Range 

Experiment Station. Corvallis, OR: US EPA. (EPA-600/3-79-071; Grant #R804283; pages i,iv-x,1,6-14,40-50,83-85,92 only; also In unpublished submission 

received Jun 24, 1983 under 464-502; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250605-N) 

43959504 Weinberg, J.T., J.M. Hugo, A.M. Landre, M.D. Martin and D.P. Milazzo (1996) 

Evaluation of the Toxicity of Picloram Triisopropanolamine (TIPA) Salt to the 

Early Life-Stages of the Fathead Minnow, Pimephales promelas Rafinesque. The 

Environmental Toxicology Research Laboratory, The Dow Chemical Company, 

Midland, MI. ID DECO-ES-3037. DowElanco, Indianapolis, IN.

151783 Gersich, F.M., D.L. Hopkins and D.P. Milazzo (1984) The Acute and Chronic 

Toxicity of Technical Picloram to Daphnia magna straus. Prepared by Dow 

Chemical, Midland, MI.

123-1 Seed germination/seedling emergence and vegetative vigor

MRID Citation Reference

43276601 Schwab, D. (1994) Evaluating the Effects of Picloram on the Germination, 

Emergence, and Vegetative Vigor of Non-Target Terrestrial Plants: Final 

Report: Lab Project Number: 41404. Unpublished study prepared by ABC 

Laboratories, Inc. 137 p. 

44156701 Schwab, D. (1996) Evaluating the Effects of Picloram (K-Salt) on the 

Vegetative Vigor of Non-Target Terrestrial Plants: Lab Project Number: 43214: 

RES96067. Unpublished study prepared by ABC Labs., Inc. 156 p. 

45809301 Wright, J. (1995) A Comparison of the Results from the 1989, 1994, and 1995 

Picloram Non-Target Plant Studies: Lab Project Number: GH-C 3888. 

Unpublished study prepared by DowElanco. 35 p. 

ACC 261128

111517

Dow Chemical U.S.A. (1986) Nontarget Area Phytotoxicity [Using Technical 

Picloram]. Unpublished compilation. 109 p. 

Hemphill, D.D. 1968. Performance of Vegetables in area traeeted with Tordon 

Herbicide.

Herr, D.; Stroube, E.; Ray, D. (1966) Effect of Tordon residues on agronomic 

crops. Down to Earth 21(4):17-18. (Also In unpub- lished submission received 

Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, 

MI; CDL:120317-G)

Jotcham, J.R. 1985 Evaluation of Crop Sensitivity to soil active Herbicides.
Page 90 of 111

128984

59420

Ragab, M. (1975) Residues of picloram in soil and their effects on crops. 

Canadian Journal of Soil Science 55:55-59. (Also In un- published submission 

received Jun 16, 1983 under 464-502; sub- mitted by Dow Chemical U.S.A., 

Midland, MI; CDL:250518-I)

Smith, L.L. Response of Seven crops to foliar applications of auxin-like 

herbicides. Open Lit.

Vanden Born, W.H. (1969) Picloram residues and crop production. Canadian 

Journal of Plant Science 49(5):628-629. (Also~In~un- published submission 

received Sep 26, 1974 under 464-323; sub- mitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:120353-K)

43959505 Scwab, D. (1995) Evaluating the Effects of Picloram (K-Salt) on the Seedling 

Emergence of Non-Target Terrestrial Plants: Lab Project Number: 42488: 

RES95069. Unpublished study prepared by ABC Labs, Inc. 141 p. 

41296501 Weseloh, J.; Stockdale, G. (1989) A Study To Determine the Effects of 

Picloram on Seed Germination, Seedling Emergence and Vegetative Vigor: Lab 

Project Number GH-P 1444; Protocol 89040. Unpublished study prepared by 

Dow Chemical U.S.A. Midland Field Research Station. 170 p. Test includes 

multiple types of Picloram

123-2 Aquatic plant growth

MRID Citation Reference

41407702 Hughes, J. (1990) The Toxicity of Picloram, Potassium Salt to Selenastrum 

capricornutum: Lab Project Number: 0460-04-1100-2. Unpublished study 

prepared by Malcolm Pirnie, Inc. 33 p. 

43230302 Boeri, R.; Kowalski, P.; Ward, T. (1994) Tordon K Herbicide: Toxicity to the 

Freshwater Diatom, Navicula pelliculosa: Lab Project Number: 436/DO: 

ES/2772. Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 24 p. 

43230305 Boeri, R.; Kowalski, P.; Ward, T. (1994) Tordon K Herbicide: Toxicity to the 

Marine Diatom, Skeletonema costatum: Lab Project Number: 437/DO: ES/2773. 

Unpublished study prepared by T. R. Wilbury Laboratories, Inc. 24 p. 

43230308 Boeri, R.; Kowalski, P.; Ward, T. (1994) Tordon K Herbicide: Toxicity to the 

Freshwater Blue-Green Alga, Anabaena flos-aquae: Lab Project Number: 

438/DO: ES/2774. Unpublished study prepared by T. R. Wilbury Laboratories, 

Inc. 25 p. 

43230311 Kirk, H.; Milazzo, D.; Humbert, L.; et al. (1994) The Toxicity of Tordon K 

Herbicide Formulation to the Aquatic Plant, Duckweed, Lemna gibba L.G-3: Lab 

Project Number: DECO/ES/2764. Unpublished study prepared by The 

Environmental Toxicology & Chemistry Research Lab. 35 p. 
Page 91 of 111

ACC 261128

129064

Dow Chemical U.S.A. (1986) Nontarget Area Phytotoxicity [Using Technical 

Picloram]. Unpublished compilation. 109 p. 

Dill, D.; Mayes, M. (1982) The Toxicity of Picloram Potassium Salt (4-Amino3,5,6-trichloropicolinic Acid Potassium Salt) to Repre- sentative Freshwater 

Organisms: ES-560. (Unpublished study re- ceived Jun 24, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-C)

Elder, J.H. 1970. Toxicity of 2,4-D and Picloram to Fresh and Saltwater Algae. 

Published literature.

Honey bee acute contact and other effects

MRID Citation Reference

41366901 Hoxter, K. and M.; Jaber, M. (1989) Tordon® 101: An Acute Contact Toxicity 

Study with the Honey Bee. Laboratory Project No. 103-313. Conducted by 

Wildlife International Ltd. Easton, MD. Submitted by the Dow Chemical 

Company, Midland, MI. 41366901.

41366902 Hoxter, K.; Thompson, M.; Jaber, M. (1989) Picloram (4-Amino-3,5, 6-

trichloropicolinic Acid) K Salt (Technical): An Acute Contact Toxicity Study 

with the Honey Bee: ?Amended Report|: Lab Project No. 103-305. Unpublished 

study prepared by Wildlife Internat- ional Ltd. 18 p. 

111490 Morton, H.; Moffett, J. (1972) Ovicidal and larvicidal effects of certain 

herbicides on honey bees. Environmental Entomology 1 (5):611-614. (Also In 

unpublished submission received Sep 26, 1974 under 464-323; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:120345-J) 

129066 Doty, A. (1965) Some Observations of the Toxicity of Tordon Herbi- cide on 

Honey Bees. (Unpublished study received Jun 24, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-E) 

Simulated or Actual Field Testing

MRID Citation Reference

111488 Moffett, J.; Morton, H.; MacDonald, R. (1972) Toxicity of some herbicidal sprays 

to honey bees. Journal of Economic Entomology 65(1):32-36. (Also In unpublished 

submission received Sep 26, 1974 under 464-323; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:120345-H) 

Non Guideline Selections

41486 Hardy, J.L. (1966) Effect of Tordon herbicides on aquatic chain or- ganisms. Down 

to Earth 22(2):11-13. (Also~In~unpublished sub- mission received Nov 6, 1967 

under 0F0863; submitted by Dow cal U.S.A., Midland, Mich.; CDL:094524-T) 
Page 92 of 111

129064 Dill, D.; Mayes, M. (1982) The Toxicity of Picloram Potassium Salt (4-Amino3,5,6-trichloropicolinic Acid Potassium Salt) to Repre- sentative Freshwater 

Organisms: ES-560. (Unpublished study re- ceived Jun 24, 1983 under 464-502; 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250605-C) 

51018 Fisher, C.E. (1975) Letter sent to Lawrence Southwick dated Apr 3, 1975 ?Drift of 

22K herbicide to non-target plants|. (Unpub- lished study received May 5, 1975 

under 464-323; prepared by Texas A & M Univ., Research and Extension Center at 

Lubbock, submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:009799-M) 

005104 Picloram Potassium salt Chemistry Fate Bibliography

161-2 Photolysis

111477 Hamaker, J.W. (1964) Decomposition of Aqueous Tordon Solutions by Sunlight. 

Prepared and Submitted by the Dow Chemical Company, Bioproducts Research 

Seal Beach, CA.

161-3 Photodegradation-soil

MRID Citation Reference

111441 Merkle, M.; Bovey, R.; Davis, F. (1967) Factors affecting the persistence of 

picloram in soil. Agronomy Journal 59(Sep-Oct): 413-415. (Also In unpublished 

submission received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., 

Indianapolis, IN; CDL:091492-V) 

111464 Baur, J.; McCall, H.; Bovey, R. (1969) Ultraviolet Degradation of Picloram. 

Annual rept., 1969. (Unpublished study received Sep 26, 1974 under 464-323; 

prepared by Texas A & M Univ., Agri- cultural Experiment Station, submitted by 

Dow Chemical U.S.A., Midland, MI; CDL:120318-D) 

111466 Bovey, R.W., M.L. Ketchersid and M.G. Merkle (1970) Comparison of Salt and 

Ester Formulations of Picloram. Weed Science 18(4):447-451.

111487 Moden, L. (1971) Picloram Dissipation and Interactions in Soils. Master's thesis, 

Univ. of Nebraska, Dept. of Agronomy. (Unpub- lished study received Sep 26, 

1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:120345-G) 

23103 Baur, J.R.; Bovey, R.W.; McCall, H.G. (1973) Thermal and ultravio- let loss of 

herbicides. Archives of Environmental Contamination and Toxicology 1(4):289-

302. (Also~In~unpublished submission received Apr 8, 1976 under 876-203; 

submitted by Velsicol Chemi- cal Corp., Chicago, Ill.; CDL:235226-T) 

162-1 Aerobic soil metabolism

MRID Citation Reference
Page 93 of 111

23093 Altom, J.D.; Stritzke, J.F. (1973) Degradation of Dicamba, Picloram, and four 

phenoxy herbicides in soils. Weed Science 21(6):556- 560. (Also in unpublished 

study received Apr 8, 1976 under 876- 203; submitted by Velsicol Chemical 

Corp., Chicago, Ill.; CDL: 235226-D) 

128967 Guenzi, W.; Beard, W. (1976) Picloram degradation in soils as influenced by soil 

water content and temperature. J. Environ. Qual. 5(2):189-192. (Also In 

unpublished submission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-V) 

111441 Merkle, M.; Bovey, R.; Davis, F. (1967) Factors affecting the persistence of 

picloram in soil. Agronomy Journal 59(Sep-Oct): 413-415. (Also In unpublished 

submission received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., 

Indianapolis, IN; CDL:091492-V) 

163-1 Leach/adsorp/desorption

MRID Citation Reference

27145 Schneider, A.D.; Wiese, A.F.; Jones, O.R. (1977) Movement of three herbicides in 

a fine sand aquifer. Agronomy Journal 69(?/May- Jun):432-436. 

(Also~In~unpublished submission received Jul 19, 1978 under 201-403; submitted 

by Shell Chemical Co., Washington, D.C.; CDL:234472-W) 

44009 Farmer, W.J.; Aochi, Y. (1974) Picloram sorption by soils. Soil Science Society of 

America Proceedings 38:418-423. (Also~In~un- published submission received 

May 5, 1975 under 464-323; submit- ted by Dow Chemical U.S.A., Midland, 

Mich.; CDL:221997-J) 

59421 Walter, J.P.; Bovey, R.W.; Merkle, M.G. (1970) The movement of Picloram 

through soil profiles. Page 249,~In~Proceedings of the Twenty-Third Annual 

Meeting of the Southern Weed Science Society; Jan 20-22, 1970, Atlanta, Ga. N.P. 

(Abstract; also ?~In~unpublished submission received Sep 26, 1974 under 464-

323; submitted by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-L) 

111428 Dow Chemical Co. (1969) ?Study: Picloram Residues in Soil & Water|. 

(Compilation; unpublished study received Apr 30, 1970 under 0F0863; 

CDL:091491-A) 

111467 Byers, G. (1971) The Movement of Two Herbicides in Three Soils. Master's thesis, 

North Carolina State Univ., Dept. of Soil Science. (Unpublished study received Sep 

26, 1974 under 464- 323; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

120318-J) 

111487 Moden, L. (1971) Picloram Dissipation and Interactions in Soils. Master's thesis, 

Univ. of Nebraska, Dept. of Agronomy. (Unpub- lished study received Sep 26, 
Page 94 of 111

1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:120345-G) 

111497 Ping, C. (1972) Movement of Picloram in Soil. Master's thesis. Washington State 

Univ., Dept. of Agronomy and Soils. (Unpub- lished study received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120345-

R) 

128975 MacDonald, K.; McKercher, R.; Moyer, J. (1973) A Report on the Study Picloram 

Displacement in Soil. (Unpublished study re- ceived Jun 16, 1983 under 464-502; 

prepared by Univ. of Sas- katchewan, Suskatchewan Institute of Pedology, 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250517-AF) 

128970 Hiltbold, A.; Hajek, B.; Buchanan, G.; et al. (1974) Leaching of Picloram and 

Nitrate in Two Alabama Soils: PB-236 856. (Unpub- lished study received Jun 16, 

1983 under 464-502; prepared by Auburn Univ., submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:250517-Z) 

128981 Norris, L.; Montgomery, M.; Warren, L. (1976) Leaching and Persis- tence 

Characteristics of Picloram and 2,4-D on a Small Watershed in Southwest Oregon. 

(Presented at the 1976 Annual Meeting: Weed Science Society of America; Feb 5, 

1976, Denver, CO; unpub- lished study received Jun 16, 1983 under 464-502; 

prepared in cooperation with U.S. Forest Service, Pacific Northwest Forest and 

Range Experiment Station and others, submitted by Dow Chemi- cal U.S.A., 

Midland, MI; CDL:250518-F) 

164-1 Terrestrial field dissipation

MRID Citation Reference

27145 Schneider, A.D.; Wiese, A.F.; Jones, O.R. (1977) Movement of three herbicides in 

a fine sand aquifer. Agronomy Journal 69(?/May- Jun):432-436. 

(Also~In~unpublished submission received Jul 19, 1978 under 201-403; submitted 

by Shell Chemical Co., Washington, D.C.; CDL:234472-W) 

49097 Bjerke, E.L.; Dishburger, H.J.; Gillespie, W.H. (1975) Residues of Picloram in Soil 

following Application of Tordon 10K Pellets-- West Virginia Experimental Permit 

Monitoring Program. (Unpub- lished study received Nov 28, 1975 under 35638-

EX-1; prepared by Dow Chemical U.S.A., submitted by Agriculture 

Commissioner, Charleston, W.Va.; CDL:223585-A) 

56010 Andriessen, F.G. (1973) Dowco^(R)I 290, Dowco 286 and Dowco 233--

Persistence in Soil and Effect on Wheat. (Unpublished study received Feb 26, 1974 

under unknown admin. no.; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:222240-H) 

59416 Scifres, C.J.; Hahn, R.R.; Diaz-Colon, J.; et al. (1971) Picloram persistence in 

semiarid rangeland soils and water. Weed Sci- ence 19(4):381-384. 

(Also~In~unpublished submission received Sep 26, 1974 under 464-323; submitted 
Page 95 of 111

by Dow Chemical U.S.A., Midland, Mich.; CDL:120353-G) 

59418 Trichell, D.W.; Morton, H.L.; Merkle, M.G. (1968) Loss of herbi- cides in runoff 

water. Weed Science 16:447-449. (Also~In~ unpublished submission received Sep 

26, 1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, Mich.; 

CDL:120353-I) 

59420 Vanden Born, W.H. (1969) Picloram residues and crop production. Canadian 

Journal of Plant Science 49(5):628-629. (Also~In~un- published submission 

received Sep 26, 1974 under 464-323; sub- mitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:120353-K) 

111428 Dow Chemical Co. (1969) ?Study: Picloram Residues in Soil & Water|. 

(Compilation; unpublished study received Apr 30, 1970 under 0F0863; 

CDL:091491-A) 

111434 Bjerke, E.; Getzendaner, M.; Van Giessen, B.; et al. (1969) Resi- dues of Picloram 

in Soil from Treatment of Rangeland with Tor- don Herbicide: Report GH-C 311. 

(Unpublished study received Apr 4, 1970 under 0F0863; submitted by Dow 

Chemical Co., Indi- anapolis, IN; CDL:091492-N) 

111436 Merkle, M.; Baur, J.; Bovey, R.; et al. (1968) The fate of herbi- cides used to 

control brush. Pages 53-56, In Brush Research in Texas. By ?. ?S.l.: s.n.|. (PR2601; also In unpublished submission received Apr 4, 1970 under 0F0863; 

submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-P) 

111465 Bovey, R.; Dowler, C.; Merkle, M. (1969) The persistence and move- ment of 

picloram in Texas and Puerto Rican soils. Pesticides Monitoring Journal 3(3):177-

181. (Available from: Superin- tendent of Documents, U.S. Government Printing 

Office, Wash- ington, DC 20402; published study; CDL:120318-G) 

111471 Glass, B.; Edwards, W. (1973) Picloram in Lysimeter Runoff and Percolation 

Water. (Unpublished study received Sep 26, 1974 under 464-323; prepared by U.S. 

Agricultural Research Service, Agricultural Environmental Quality Institute, North 

Appalachian Experimental Watershed in cooperation with Ohio Agr. Res. and Dev. 

Cent., submitted by Dow Chemical U.S.A., Midland, MI; CDL: 120318-P) 

111495 Phillips, W.; Feltner, K. (1972) Persistence and Movement of Pi- Chloram in two 

Kansas soils. Weed Science 20(1):110-116. (Also In unpublished submission 

received Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, MI; CDL:120345-P) 

111497 Ping, C. (1972) Movement of Picloram in Soil. Master's thesis. Washington State 

Univ., Dept. of Agronomy and Soils. (Unpub- lished study received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120345-
Page 96 of 111

R) 

111519 Hunter, J.; Stobbe, E. (1972) Movement and persistence of picloram in soil. Weed 

Science 20(5):486-489. (Also In unpublished submission received Sep 26, 1974 

under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120317-J) 

111554 West Virginia Dept. of Agriculture (1975) The Use of Tordon 10-K Herbicide to 

Control Multiflora Rose in Pastures in West Vir- ginia. Third quarterly rept. 

(Unpublished study; CDL:223586-A) 

112012 Moffat, R. (1968) Some factors affecting the disappearance of Tor- don in soil. 

Down to Earth 23(4):6-10. (Also In unpublished submission received Apr 4, 1970 

under 0F0863; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-

W) 

112013 Baur, J.; Baker, R.; Bovey, R.; et al. (1972) Concentration of picloram in the soil 

profile. Weed Science 20(4):305-309. (Also In unpublished submission received 

Sep 26, 1974 under 464- 323; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL: 120318-E) 

112014 Baur, J.; Bovey, R.; Merkle, M. (1972) Concentration of picloram in runoff water. 

Weed Science 20(4):309-313. (Also In unpublished submission received Sep 26, 

1974 under 464-323; submitted by Dow Chemical U.S.A., Midland, MI; 

CDL:120318-F) 

112976 Davis, E.; Ingebo, P. (1973) Picloram movement from a chaparral watershed. 

Water Resources Research 9(5):1304-1313. (Also In unpublished submission 

received Nov 28, 1975 under 464-320; sub- mitted by Dow Chemical U.S.A., 

Midland, MI; CDL:221810-A) 

128950 Bjerke, E.; Ervick, D. (1976) A Residue Study of Picloram in Soil following 

Application of Tordon Herbicides: Laboratory Report Code GH-C 895. 

(Unpublished study received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL: 250517-D) 

128975 MacDonald, K.; McKercher, R.; Moyer, J. (1973) A Report on the Study Picloram 

Displacement in Soil. (Unpublished study re- ceived Jun 16, 1983 under 464-502; 

prepared by Univ. of Sas- katchewan, Suskatchewan Institute of Pedology, 

submitted by Dow Chemical U.S.A., Midland, MI; CDL:250517-AF) 

128985 Rao, P.; Green, R.; Balasubramanian, V.; et al. (1974) Field study of solute 

movement in a highly aggregated Oxisol with intermit- tent flooding: II. Picloram. 

J. Environ. Quality 3(3):197-202. (Also In unpublished submission received Jun 

16, 1983 under 464- 502; submitted by Dow Chemical U.S.A., Midland, MI; CDL: 

250518-J) 

128990 Wright, W. (1974) The Movement of Herbicides off, into and through Soils of Two 

North Carolina Watersheds with Particular Reference to Picloram: Laboratory 

Report Code GH-P 874. Interim rept. (Unpublished study received Jun 16, 1983 

under 464-502; submit- ted by Dow Chemical U.S.A., Midland, MI; CDL:250518-
Page 97 of 111

P) 

160126

ACC 263388

Oliver, G.; Bjerke, E.; Gantz, R. (1986) Field Dissipation and Leaching Study for 

Grazon P+L Herbicide: GH-C 1819. Unpub- lished study prepared by Dow 

Chemical USA. 55 p. 

164-2 Aquatic field dissipation

MRID Citation Reference

111475 Haas, R.; Scifres, C.; Merkle, M.; et al. (1971) Occurrence and persistence of 

picloram in grassland water sources. Weed Res. 11:54-62. (Also In unpublished 

submission received Sep 26, 1974 under 464-323; submitted by Dow Chemical 

U.S.A., Midland, MI; CDL:120318-X) 

128955 Bovey, R.; Richardson, C.; Burnett, E.; et al. (1978) Loss of spray and pelleted 

Picloram in surface runoff water. J. Environ. Qual. 7(2):178-180. (Also In 

unpublished submission received Jun 16, 1983 under 464-502; submitted by Dow 

Chemical U.S.A., Midland, MI; CDL:250517-I) 

128981 Norris, L.; Montgomery, M.; Warren, L. (1976) Leaching and Persis- tence 

Characteristics of Picloram and 2,4-D on a Small Watershed in Southwest Oregon. 

(Presented at the 1976 Annual Meeting: Weed Science Society of America; Feb 5, 

1976, Denver, CO; unpub- lished study received Jun 16, 1983 under 464-502; 

prepared in cooperation with U.S. Forest Service, Pacific Northwest Forest and 

Range Experiment Station and others, submitted by Dow Chemi- cal U.S.A., 

Midland, MI; CDL:250518-F) 

128990 Wright, W. (1974) The Movement of Herbicides off, into and through Soils of Two 

North Carolina Watersheds with Particular Reference to Picloram: Laboratory 

Report Code GH-P 874. Interim rept. (Unpublished study received Jun 16, 1983 

under 464-502; submit- ted by Dow Chemical U.S.A., Midland, MI; CDL:250518-

P) 

164-3 Forest field dissipation

MRID Citation Reference

41395301 Knuteson, J.; Racke, K.; Woodburn, K.; et al. (1990) Picloram Fate in a Coastal 

Plain Forest Ecosystem: Lab Project Number: GH-C 2299: Protocol No.87115. 

Unpublished study prepared by Dow Elanco RSRA Analytical Services, Inc and 

other laboratories. 210 p. 

128979 Neary, D.; Douglass, J.; Fox, W. (1979) Low Picloram Concentrations in 

Streamflow Resulting from Forest Application of Tordon-10K. (Unpublished study 

received Jun 16, 1983 under 464-502; prepared by U.S. Forest Service, 

Southeastern Forest Experiment Station, Coweeta Hydrologic Laboratory, Range, 
Page 98 of 111

Timber, and Wildlife, sub- mitted by Dow Chemical U.S.A., Midland, MI; 

CDL:250518-D) 

140317 Neary, D.G., J.E. Douglass and W. Fox (1984) Water Quality and Nutrient Cycling 

Impacts of Using the Herbicide Tordon 10K in Preparing Scrub Hardwood for 

Conversation to White Pine (Pinus strobus L.). Prepared by the USDA Forest 

Service and Submitted by the Dow Chemical Company.

166-1 Ground water-small prospective

MRID Citation Reference

45400701 Havens, P.; Murrow, D.; Pottinger, M. (2001) State Groundwater Surveillance 

Monitoring Program for Picloram Herbicide: Field Progress Report: Lab Project 

Number: 980054: 96-330: ENV960714. Unpublished study prepared by Stone 

Environmental, Inc. and Agvise Laboratories. 861 p. 

42535302 Peterson, J.R. Field Dissipation and Leaching Studies in a Northern Rangeland 

Environment: Picloram/Clopyralid and Fluroxypyr (protocol)

Crop Rotation Studies

157172 Stafford, L.E. and J.H. Miller (1986) 14C Picloram Rotational Crop Study. Prepared 

and Submitted by Dow Chemical USA, Midland, MI.

Non Guideline Selections

44005 Bovey, R.W.; Scifres, C.J. (1971) Residual Characteristics of Picloram in Grassland 

Ecosystems. College Station, Tex.: Texas A & M Univ., Agricultural Experiment 

Station. (B-1111; also~In~ unpublished submission received May 5, 1975 under 

464-323; sub- mitted by Dow Chemical U.S.A., Midland, Mich.; CDL:221997-E) 

59413 Schneider, A.D.; Wiese, A.F.; Jones, O.R.; et al. (1971) Deter- mining the Fate of 

Herbicides in the Ogallala Aquifer. Col- lege Station, Tex.: Texas A & M Univ., 

Agricultural Experiment Station. (B-1112; also~In~unpublished submission 

received Sep 26, 1974 under 464-323; submitted by Dow Chemical U.S.A., 

Midland, Mich.; CDL:120353-D) 

59419 Tu, C.M.; Bollen, W.B. (1969) Effect of Tordon herbicides on micro- bial activities 

in three Willamette Valley soils. Down to Earth 25(2):15-17. (Also~In~unpublished 

submission received Sep 26, 1974 under 464-323; submitted by Dow Chemical 

U.S.A., Midland, Mich.; CDL:120353-J) 

111474 Grover, R. (1972) Effect of picloram on some soil microbial activities. Weed Res. 

12:112-114. (Also In unpublished sub- mission received Sep 26, 1974 under 464-

323; submitted by Dow Chemical U.S.A., Midland, MI; CDL:120318-W) 

140319 Glass, B.L.; Edwards, W.M. (1973) Picloram in Lysimeter Runoff and Percolation 

Water. (Unpublished study received Mar 9, 1977 under 464-423; prepared by U.S. 

Agricultural Research Service, Agricultural Environmental Quality Institute and 
Page 99 of 111

others, sub- mitted by Dow Chemical U.S.A., Midland, Mich.; CDL:228627-Q) 

114837 or 

22737

Corbin, F. (1965) The Influence of pH on the Detoxication of Herbi- cides in Soil. 

Doctoral thesis, North Carolina State Univ., Dept. of Crop Science. (Unpublished 

study received Mar 18, 1976 under 3E1385; submitted by U.S. Dept. of Interior, 

Bureau of Reclamation, Washington, DC; CDL:095210-N) 

111442 Grover, R. (1968) Influence of soil properties on phytotoxicity of ... (picloram). 

Weed Res. 8:226-232. (Also In unpublished submission received Apr 4, 1970 under 

0F0863; submitted by Dow Chemical Co., Indianapolis, IN; CDL:091492-X) 

111433 Merkle, M.; Bovey, R.; Hall, R. (1966) The determination of Piclo- ram residues in 

soil using gas chromatography. Weeds 14(2): 161-164. (Also In unpublished 

submission received Apr 4, 1970 under 0F0863; submitted by Dow Chemical Co., 

Indianapolis, IN; CDL:091492-K) 

111472 Green, L. (1972) Letter sent to L. Warren dated Sep 7, 1972 ?Effi- cacy of various 

chemicals applied to watersheds|: 4400. (U.S. Forest Service, Pacific Southwest 

Forest and Range Experiment Station, Forest Fire Laboratory; unpublished study; 

CDL: 120318-S) 

111469 Davis, E.; Ingebo, P.; Pase, C. (1968) Effect of a Watershed Treat- ment with

Picloram on Water Quality. ?S.l.|: U.S. Forest Service. (Research note RM-100; 

published study; CDL:120318-L) 

128714 Dow Chemical U.S.A. (1983) Residue Chemistry: ?Tordon K Salt Liq- uor: Grains 

and Animal Tissue|. (Compilation; unpublished study received Jun 20, 1983 under 

464-502; CDL:250508-A; 250509) 

111554 West Virginia Dept. of Agriculture (1975) The Use of Tordon 10-K Herbicide to 

Control Multiflora Rose in Pastures in West Vir- ginia. Third quarterly rept. 

(Unpublished study; CDL:223586-A) 
Appendix B: Toxicity Comparison for Picloram Potassium Salt, 2,4-D TIPA Salt and Formulations 

Containing Both Picloram TIPA Salt and 2,4-D TIPA Salt

Species Formulation % 2,4-D 

TIPA salt

% Picloram 

TIPA/K salt

ECx/

LCx

(mg/kg 

or 

lbs/A)

95% CI Adj. 

EC501

MRID

Green algae 2,4-D TIPA salt 

only

73.8 NA 75.7 31-160 NA 417321-01

Picloram TIPA 

salt +2,4-D 

TIPA salt

39.6 10.2 234.0 179—

305

130.7 414077-01

Picloram K salt NA 35.2 65.0 47—89 56.0 414077-02

Freshwater 

diatom

2,4-D TIPA salt 

only

70.9 NA 94.4 60-148 NA 434886-01

Picloram TIPA 

salt +2,4-D 

TIPA salt

21.2 10.2 400.0 320—

500

223.0 432303-03

Picloram K salt NA 27.9 3.7 3.1—4.3 3.2 432303-02

Blue-green 

algae

2,4-D TIPA salt 

only

70.9 NA 133.0 97-183 NA 434886-04

Picloram TIPA 

salt +2,4-D 

TIPA salt

21.2 10.2 630.0 563—

723

352.0 432303-09

Picloram K salt NA 27.9 585.0 536—

647

504.0 432303-08

Duckweed 2,4-D TIPA salt 

only

70.9 NA 2.37 1.9--2.9 NA 434886-02
Picloram TIPA 

salt +2,4-D 

TIPA salt

39.6 9.7 4.67 2.59—

8.42

2.61 432303-12

Picloram K salt NA 27.9 95.50 75—124 82.30 432303-11

Rainbow 

Trout

2,4-D TIPA salt 

only

69.2 NA 300.00 268--323 NA 413538-03

Picloram TIPA 

salt +2,4-D 

TIPA salt

40.8 2.5 1250.0

0

698.32 41146

Picloram K salt NA 24.4 26.00 22.40 129072

Terrestrial 

Plants-Veg 

Vigor—

Dicot

(Tomato)

2,4-D DMA Salt 39.3% NA 0.0073 0.0045—

0.0126

471060-02

Picloram TIPA 

salt +2,4-D 

TIPA salt

22.4% 6.1% 0.0002 412965-01

Picloram K salt NA 24.1% 0.0001

8

0.0047—

0.095

441567-01

Terrestrial 

PlantsSeedling 

Emergence

(Tomato)

2,4-D DMA Salt 55.5% NA 0.26 NA 423895-01

Picloram TIPA 

salt +2,4-D 

TIPA salt

22.4% 6.1% 0.0003

6

NA 412965-01 

(Qualitativ

e Data)

Picloram K salt NA 24.1% 0.0066 0.0047-

0.095

439595-05

1

Adjusted LC/EC50 is based on acid equivalents for picloram acid using a molecular weight ratio of 1.79 for the picloram TIPA salt 

and 1.16 for the picloram potassium salt.

NA = Not Applicable

EFED conducted an analysis comparing the toxicity of formulations containing either picloram K salt or 2,4-D TIPA salt with multi-ai 

data from formulations containing both picloram TIPA salt and 2,4-D TIPA salt in order to see if the combination of multiple 

herbicides had enhanced toxicity. For taxa where data was available on these three formulations (including aquatic plants, aquatic 
invertebrates and fish), there was no evidence of enhanced toxicity from the picloram and 2,4-D TIPA salts mixture. However, no 

data was available for the effect of formulations solely containing one active ingredient of 2,4-D TIPA salt on terrestrial plants. In this 

case, EFED used 2,4-D DMA salt as a comparison, which was identified as the most toxic 2,4-D salt to dicots in the 2013 2,4-D 

Problem Formulation (USEPA, 2013). The most sensitive terrestrial plant species for which data was available for both picloram salts 

and 2,4-D DMA salt was the tomato. Although there was no evidence of enhanced toxicity in the vegetative vigor studies, for the 

seedling emergence studies the tomato was an order of magnitude more sensitive to the picloram/2-4 D TIPA salts formulation than 

the picloram K salt formulation and 4 orders of magnitude more sensitive than the 2,4-D DMA salt formulation. The same qualitative 

data source (MRID 412965-01) used for the picloram TIPA salt and 2,4-D TIPA salt co-formulation also contained qualitative 

information for picloram K salt that was more sensitive than the quantitative data cited above, however it was still less sensitive than 

the picloram TIPA salt/2,4-D TIPA salt co-formulation data.. 

Appendix C: Summary Data for Picloram Related Incidents (PC Codes 005101, 005102, 005104)

EIIS Pesticide Summary Report: General Information

Picloram (005101)
Incident # Date County State Certainty Legal. Formul. Appl. Method Total Magnitude

AQUATIC

Agricultural Area

I001616-001 11/23/1994 4 RU EC N/R 1

N/R

I003325-001 2 MA Spray 105

WEEDS NEAR POND

I007873-001 8/21/1998 TX 2 MA N/R 300

PLANTS

No Data

I020998-034

I021276-012

Agricultural area

3/21/2003

4/15/2004

Chelan

Spokane

WA 2 UN 

WA 2 M

I020627-009 Spokane WA 3 RU 3 acres

I001458-001 3 UN N/R N/R 90 ACRES OF 

POTATO'S

I004815-001 MO 3 UN Spray 40 ACRES 

SOYBEANS
I002168-001 5/1/1995 FL 3 MA F Broadcast, 

unincorporated

Unknown

I003129-001 1/1/1996 KS 3 RU N/R N/R ALL

I008333-002 7/4/1997 YELLOWSTONE MT 2 RU N/R FOLIAR 

BROADCAST

2600 ACRES

I008333-004 4/21/1998 JEWELL KS 3 RU F Broadcast 228 ACRES

I007754-003 4/28/1998 GOODHUE MN 2 RU Broadcast 80 ACRES

I015921-002 8/6/2003 Osage OK 2 UN Spray Trees (hundreds)

Garden

I013587-027 6/21/1999 Spokane WA 3 RU Unknown

Hay

I015748-001 Culpeper VA 2 RU Broadcast 10.2 acres

HOME/LAWN

I006281-001

Municpal operation

6/1/1997 KS 3 RU N/R N/R 9

N/R

I007708-001

I008451-001

3/1/1997

12/7/1998

BROWN 

ROANOKE

OH 2 UN N/R UNKNOWN 

VA 3 RU N/R UNKNOWN

I002324-001 6/1/1995 PA 3 UN N/R SPRAY N/R

I020627-039

Pasture

10/24/2001 Yakima WA 2 UN
I011249-001 6/17/2000 Webster NE 2 RU SC Spray UNKNOWN

Right-of-way

I020459-008 Okanogan WA 2 UN Spray

I006871-001 OH 3 RU N/R UNKNOWN

I001944-001 OK 2 MA Spray HUNDREDS OF 

TREES

I002539-001 8/1/1995 OK 2 UN N/R SPRAY 1 1/3 AR

I013884-039 8/25/1998 Spokane WA 2 MA One tree

I015218-001 7/15/2004 Massac IL 1 RU Spray 50-75 trees

Right-of-way, railroad

I004352-001 OK 4 MA 50000

WHEAT

I004819-001 KS 3 RU N/R UNKNOWN

I008333-001 6/25/1998 OSBORNE KS 2 MA N/R Broadcast 40 ACRES

TERRESTRIAL

Turf, residential

I023571-002 7/12/5010 Klamath OR 2 M Spray Over 1000

TERRESTRIAL/AQUATIC

N/R

I006139-001 10/1/1997 OK 2 UN N/R N/R UNKNOWN
Certainty Code: 0=Unrelated, 1=Unlikely, 2=Possible, 3=Probable, 4=Highly Probable.

Legality Code: RU=Registered Use, M=Misuse, MA=Misuse (Accidental), MI=Misuse (Intentional), U=Unknown.

Monday, December 02, 2013 Page 1 of 2

EIIS Pesticide Summary Report: General Information

Picloram, triisopropanolamine salt (005102)

Incident # Date County State Certainty Legal. Formul. Appl. Method Total Magnitude

PLANTS

Brome

Hay

N/R

I012366-045

I012366-047

I010624-001

I014702-019

I018930-031

I014561-012

7/27/2000

4/25/2000

8/1/2000

4/28/2003

5/5/2007

10/8/2003

MORRIS

LONOKE 

Whitman 

Cass 

Tarrant

Harris

KS 3 RU Broadcast 500 acres

AR 2 RU Broadcast 42 acres

WA 3 RU N/R N/R

MS 2 RU SC Broadcast 40 acres

TX 2 MA 2 acres

TX 2 UN EC Various

Pasture

I014702-018

I012366-046

I014034-009

8/14/2000

4/29/2003

Lawrence

JEFFERSON 

Hall

MO 2 RU SC Broadcast 60 acres

TX 3 RU Broadcast 30 acres

GA 2 RU 60 acres

Peanut

I013550-001 6/19/2002 KLEBERG TX 3 MA 360 acres

RANGELAND
Certainty Code: 0=Unrelated, 1=Unlikely, 2=Possible, 3=Probable, 4=Highly Probable.

Legality Code: RU=Registered Use, M=Misuse, MA=Misuse (Accidental), MI=Misuse (Intentional), U=Unknown.

Monday, December 02, 2013 Page 1 of 2

EIIS Pesticide Summary Report: General Information

Picloram, potassium salt (005104)

Incident # Date County State Certainty Legal. Formul. Appl. Method Total Magnitude

AQUATIC

Fence row

I000046-001 7/21/1989 MADISON MT 3 RU N/R Spray THOUSANDS

PLANTS

Corn

Hay

I012366-078

I018677-001

6/14/2000

6/2/2007

GREELEY

Rappahannock

KS 3 M Broadcast 130 acres

VA 4 UN Spray 10 acres

Orchard (unspecified)

I020459-002 Chelan WA 3 UN

Peanut

I013550-001 6/19/2002 KLEBERG TX 3 MA 360 acres

Unknown

I014702-077 7/20/2003 Ford KS 2 RU EC Broadcast 351 acres

Wheat

I012366-079 6/11/1999 PAWNEE KS 3 RU Broadcast 38 acres

I012366-076 6/20/2000 Ward ND 3 RU Broadcast 120 acres
Appendix D- SIP and STIR Outputs

STIR

Input

Application and Chemical Information

Enter Chemical Name Picloram

Enter Chemical Use

Rights-of-way, 

pasture

Is the Application a Spray? (enter y or n) y

If Spray What Type (enter ground or air) air

Enter Chemical Molecular Weight (g/mole) 241.5

Enter Chemical Vapor Pressure (mmHg)

Enter Application Rate (lb a.i./acre)

Toxicity Properties

Bird

Enter Lowest Bird Oral LD50 (mg/kg bw) 2150

Enter Mineau Scaling Factor 1.15

Enter Tested Bird Weight (kg) 1.58

Mammal

Enter Lowest Rat Oral LD50 (mg/kg bw) 3536

Enter Lowest Rat Inhalation LC50 (mg/L) 0.035

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) 0.00E+00

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 0.00E+00

Adjusted Inhalation LD50 8.55E-02

Ratio of Vapor Dose to Adjusted Inhalation LD50 0.00E+00 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 0.00E+00

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 0.00E+00 Exposure not Likely Significant

Results Mammalian (0.015 kg )

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 0.00E+00

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 0.00E+00

Adjusted Inhalation LD50 2.08E+00

Ratio of Vapor Dose to Adjusted Inhalation LD50 0.00E+00 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 0.00E+00

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 0.00E+00 Exposure not Likely Significant

SIP

Table 1. Inputs

Parameter Value

Chemical name Picloram

Solubility (in water at 25oC; mg/L) 430

Mammalian LD50 (mg/kg-bw) 3536

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian 

species

Mammalian NOAEL (mg/kg-bw) 200
Mammalian test species laboratory rat

Body weight (g) of "other" mammalian 

species

Avian LD50 (mg/kg-bw) 2510

Avian test species mallard duck

Body weight (g) of "other" avian species

Mineau scaling factor 1.15

Mallard NOAEC (mg/kg-diet) 0

Bobwhite quail NOAEC (mg/kg-diet) 0

NOAEC (mg/kg-diet) for other bird species 0

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) 73.9600 73.9600

Adjusted toxicity value (mg/kg-bw) 2719.7518 153.8321

Ratio of exposure to toxicity 0.0272 0.4808

Conclusion*

Drinking water exposure 

alone is NOT a potential 

concern for mammals

Drinking water exposure 

alone is NOT a potential 

concern for mammals

Table 3. Avian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 348.3000 348.3000

Adjusted toxicity value (mg/kg-bw) 1303.2558 0.0000

Ratio of exposure to acute toxicity 0.2673 0.0000
Conclusion*

Exposure through 

drinking water alone is a 

potential concern for 

birds

Due to insufficient data, 

risk cannot be precluded

*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.