Docket Number: EPA-HQ-OPP-2010-0453 

www.regulations.gov 

United States Chemical Safety September 2010 

Environmental Protection and Pollution Prevention 

Agency (7510P) 

 

Terbuthylazine Summary Document: 

Registration Review 

 

 

Docket Number: EPA-HQ-OPP-2010-0453 

www.regulations.gov 

TABLE OF CONTENTS 

 

Terbuthylazine Registration Review Team.................................................................... 4 

I. PRELIMINARY WORK PLAN – TERBUTHYLAZINE........................................ 5 

II. FACT SHEET ............................................................................................................ 13 

III. GLOSSARY of TERMS & ABBREVIATIONS ................................................... 16 

IV. Appendix A................................................................................................................ 18 

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Terbuthylazine Registration Review Team 

Human Health & Environmental Effects 

Nathan Mottl 

Najm Shamim 

Risk Management

Eliza Blair 

Lance Wormell 

Office of General Counsel

Philip Ross 

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I. PRELIMINARY WORK PLAN – TERBUTHYLAZINE

Introduction

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review 

program. All pesticides distributed or sold in the United States generally must be 

registered by the U.S. Environmental Protection Agency (USEPA, EPA, or the Agency), 

based on scientific data showing that they will not cause unreasonable risks to human 

health or the environment when used as directed on product labeling. The registration 

review program is intended to make sure that, as the ability to assess risk evolves and as 

policies and practices change, all registered pesticides continue to meet the statutory 

standard of no unreasonable adverse effects to human health or the environment. 

Changes in science, public policy, and pesticide use practices will occur over time. 

Through the registration review program, the Agency periodically reevaluates pesticides 

to make sure that as change occurs, products in the marketplace can be used safely. 

Information on this program is provided at 

http://www.epa.gov/oppsrrd1/registration_review/. 

The Agency is implementing the registration review program pursuant to Section 

3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and will review 

each registered pesticide every 15 years to determine whether it continues to meet the 

FIFRA standard for registration. The Agency will consider benefits information and data 

as required by FIFRA. The public phase of registration review begins when the initial 

docket is opened for each case. The docket is the Agency’s opportunity to state what it 

knows about the pesticide and what additional risk analyses and data or information it 

believes are needed to make a registration review decision. After reviewing and 

responding to comments and data received in the docket during this initial comment 

period, the Agency will develop and commit to a final work plan and schedule for the 

registration review of terbuthylazine. 

 Terbuthylazine, first registered as an herbicide in 1975, is now registered for use 

solely as a slimicide in industrial recirculating cooling water applications and ornamental 

fountains. There are four registered products. A Reregistration Eligibility Decision (RED) 

for Terbuthylazine was issued by EPA in 1995. The RED can be located at 

http://www.epa.gov/pesticides/reregistration/status.htm. 

Risk Assessment Status & Anticipated Data Needs

Human Health Risk Assessment Status and Anticipated Data Needs 

The Agency has reviewed all the available information on toxicology and human 

exposure regarding terbuthylazine and does not anticipate that additional data will be 

needed for this registration review case. If the results from the environmental fate data 

(see below) indicate that terbuthylazine has the potential to pass through wastewater 

treatment plants and into drinking water, the need for a drinking water assessment will be 

revisited. 

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Further information is available in “Terbuthylazine: Human Health Effects 

Scoping Document for the Registration Review Decision”, dated July 19, 2010. 

Dietary and Drinking Water Assessment

The need for a drinking water exposure assessment will be revisited upon 

submission and review of the environmental fate data the Agency anticipates requiring 

through Registration Review. These environmental fate data will be used to determine if 

terbuthylazine has the potential to pass through wastewater treatment facilities into 

drinking water or migrate into residential groundwater wells as a result of its current use 

patterns. 

Tolerances

 There are no current tolerances or exemptions from tolerances for the 

terbuthylazine active ingredient and no registered food uses. 

Aggregate/Cumulative Exposure & Risk

 In examining aggregate exposure, EPA takes into account the available and 

reliable information concerning exposures to pesticide residues in food and drinking 

water, as well as non-occupational pesticide exposures. Based on current use patterns, an 

aggregate risk assessment will not be needed for terbuthylazine. Residential exposure is 

not expected and the need for a drinking water exposure assessment will be determined 

upon submission and review of the environmental fate data the Agency anticipates 

requiring.

 Section 40(b)(2)(D)(v) of FFDCA requires that, when considering whether to 

establish, modify, or revoke a tolerance, the Agency considers “available information” 

concerning the cumulative effects of a particular pesticide’s residues and “other 

substances that have a common mechanism of toxicity.” EPA has not yet determined 

whether terbuthylazine has a common mechanism with other compounds, however, 

during the risk assessment stage for registration review, the Agency will address the 

possibility that terbuthylazine shares a common mechanism of toxicity with other 

members of the Triazine Common Mechanism Group (CMG) and whether terbuthylazine 

should be included in a cumulative exposure group with the rest of the triazines. 

 The Agency examined the triazine class of pesticides with respect to a potential 

common mechanism of toxicity. This examination may be found at 

http://www.epa.gov/oppsrrd1/cumulative/triazines/triazinescommonmech.pdf. Several 

members of this class have been identified as causing toxicity through a similar 

mechanism of action. Specifically, atrazine, simazine, propazine, and certain degradates 

are considered to act through disruption of the hypothalamic-pituitary-gonadal axis to 

attenuate the luteinizing hormone surge. As a result of this attenuation, exposure of the 

animal to estrogen is continuous, providing an environment conducive to the 

development of mammary gland tumors. Mammary gland tumors have been observed in 

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female rats after administration of these chemicals, and the postulated mode of action of 

the triazine pesticide atrazine has been reviewed by the FIFRA Scientific Advisory Panel 

and has been found to be plausible (U.S. EPA, 2000). 

Occupational and Residential Assessment

 An occupational and/or residential exposure assessment is required for an active 

ingredient if (1) certain toxicological criteria are triggered and (2) there is potential 

exposure to handlers (mixers, loaders, applicators, etc.) during use. 

 Currently application to recirculating cooling water systems and ornamental 

fountains is required by the label to be through closed-system only. In the event that the 

product needs to be handled, personal protective equipment is required by the label in the 

form of a long-sleeved shirt, long pants, shoes, socks, chemical-resistant gloves, and the 

availability of a chemical-resistant apron for spills. As a result, the Agency does not 

anticipate the need to conduct occupational and residential handler dermal and inhalation 

risk assessments since exposure is minimized by the required engineering controls as well 

as the required personal protective equipment. At this time, the Agency anticipates that 

no exposure data will be needed. 

Anticipated Human Health Data Needs:

 All human toxicology and exposure data requirements have been fulfilled for the 

active ingredient terbuthylazine. The Agency has reviewed the available data for 

terbuthylazine and expects that no additional toxicity or exposure data will be needed for 

registration review. 

Further information is available in “Summary of Human Health Effects Data for 

the Terbuthylazine Registration Review Decision Document”, dated July 19, 2010. 

Anticipated Physical/ Chemical Property Data Needs 

 All product chemistry data requirements have been fulfilled for the active 

ingredient terbuthylazine. Therefore, the Agency does not anticipate needing additional 

product chemistry data at this time. 

Further information is available in “Terbuthylazine: Product Chemistry / 

Environmental Fate and Eco-Effects Scoping Document”, dated July 28, 2010 . 

Anticipated Environmental Fate and Ecotoxicity Risk Assessment and Data Needs 

The Agency has reviewed the environmental fate and ecological hazard databases 

for terbuthylazine. Based on its review, EPA believes the following environmental fate 

and ecological hazard risk assessments are needed to ensure that the registration review 

case meets FIFRA standards: 

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• Environmental fate 

• Ecological hazard 

• Endangered species assessment 

Further information and detailed justifications for the studies that are anticipated 

as being needed are available in “Terbuthylazine: Product Chemistry / Environmental 

Fate and Eco-Effects Scoping Document”, dated July 28, 2010 . 

The Agency expects that it will need to conduct environmental fate and ecological 

risk assessments for slimicides that potentially pass through waste water treatment plants 

(WWTPs) and may be discharged into terrestrial and aquatic environments. 

Anticipated Environmental Fate Data Needs:

o (GLN 835.3110) Ready Biodegradability 

o (GLN 835.1110) Activated Sludge Isotherm 

Anticipated Ecological Effects Data Needs:

o (GLN 850.5400) Aquatic plant growth (algal), Tier II 

Endangered Species 

 The Agency has not conducted a risk assessment that supports a complete 

endangered species determination for terbuthylazine. The ecological risk assessment 

planned during registration review will allow the Agency to determine whether 

terbuthylazine use has “no effect” or “may affect” federally listed threatened or 

endangered species (listed species) or their designated critical habitats. When an 

assessment concludes that a pesticide’s use “may affect” a listed species or its designated 

critical habitat, the Agency will consult with the U.S. Fish and Wildlife Service and/or 

National Marine Fisheries Services (the Services), as appropriate. 

Incidents:

 A search of OPP’s Incident Database System (IDS) revealed two incidents 

associated with terbuthylazine. No further information was available regarding these 

incidents. 

Timeline:

 The Agency has created the following estimated timeline for the completion of 

the terbuthylazine registration review: 

Activities Estimated Month/Year

Phase 1: Opening the docket 

Open Public Comment Period for Terbuthylazine Docket September 2010 

Close Public Comment Period November 2010 

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Phase 2: Case Development 

Develop Final Work Plan (FWP) February 2011 

Issue DCI February 2012 

Data Submission February 2014 

Open Public Comment Period for Preliminary Risk Assessments September 2015 

Close Public Comment Period December 2015 

Phase 3: Registration Review Decision 

Open Public Comment Period for Proposed Reg. Review Decision March 2016 

Close Public Comment Period June 2016 

Final Decision and Begin Post-Decision Follow-up 2016 

Total (years) 6 

Guidance for Commenters:

The public is invited to comment on EPA’s preliminary registration review workplan and rationale. The Agency will consider all comments as well as any additional 

information or data provided in a timely manner prior to issuing a final work plan for the 

terbuthylazine case. 

Trade Irritants 

Through the registration review process, the Agency intends to solicit information 

on trade irritants and, to the extent feasible, take steps toward facilitating irritant 

resolution. Growers and other stakeholders are asked to comment on any trade irritant 

issues resulting from lack of Maximum Residue Limits (MRLs) or disparities between 

U.S. tolerances and MRLs in key export markets, providing as much specificity as 

possible regarding the nature of the concern. 

Water Quality 

Terbuthylazine are not identified as a cause of impairment for any water bodies 

listed as impaired under section 303(d) of the Clean Water Act, based on information 

provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_grou

p_id=885. In addition, no Total Maximum Daily Loads (TMDL) have been developed 

for [insert pesticide], based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_gr

oup_id=885&p_pollutant_group_name=PESTICIDES. More information on impaired 

water bodies and TMDLs can be found at http://www.epa.gov/owow/tmdl/. The Agency 

invites submission of water quality data for this pesticide. To the extent possible, data 

should conform to the quality standards in Appendix A of the OPP Standard Operating 

Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s 

Registration Review Risk Assessment and Management Process (see: 

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http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm), in order to 

ensure they can be used quantitatively or qualitatively in pesticide risk assessments.

Environmental Justice 

EPA seeks to achieve environmental justice, the fair treatment and meaningful 

involvement of all people, regardless of race, color, national origin, or income, in the 

development, implementation, and enforcement of environmental laws, regulations, and 

policies. To help address potential environmental justice issues, the Agency seeks 

information on any groups or segments of the population who, as a result of their 

location, cultural practices, or other factors, may have atypical, unusually high exposure 

to terbuthylazine, compared to the general population. Please comment if you are aware 

of any sub-populations that may have atypical, unusually high exposure compared to the 

general population. 

Structure Activity Relationships 

EPA must rely upon information of appropriate quality and reliability for each 

decision made by the Agency. In the Office of Pesticide Programs (OPP), the evaluation 

process for a pesticide chemical traditionally begins with the applicant’s submission of a 

set of studies conducted with the specific pesticide chemical of interest. The use of the 

results of such testing (measured data) is a logical, scientifically rigorous process that 

identifies the physical, chemical, and environmental fate properties of the pesticide, as 

well as the dose and endpoints at which an adverse effect can occur in various animal 

species. 

Today, there is significant interest in alternative techniques, i.e., techniques other 

than data generation that could significantly inform the Agency’s decision-making 

process. Recently, OPP has made increasing use of structure activity relationship (SAR) 

as part of its regulatory decision-making process. In the SAR process, a chemical's 

molecular structure is compared to that of other chemicals for which data are available. 

These structural similarities are then used to make predictive judgments about a 

chemical’s physical, chemical, and biological properties. Thus, the chemical’s physical, 

chemical, and biological properties are a function of (or directly related to) the chemical’s 

molecular structure. Quantitative SAR is referred to as QSAR. To develop a QSAR, a 

selected set of measured data on a single physical, chemical, or biological property is 

used to derive a model (an equation) to predict the value of that property. 

 Since SAR assessments and QSAR modeling are another set of tools that are 

available to Agency scientists, OPP has begun a process shift that envisions shifting from 

the current study-by-study approach to an approach in which the use of predicted data, 

generated using validated models, is considered along with information from open 

literature and studies specifically generated under Part 161 requirements. All relevant 

information would be considered as part of a weight-of-the-evidence evaluation. 

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At this time, EPA believes that for certain endpoints, especially physical/chemical 

and fate properties, that SAR and QSAR might be effectively utilized to fulfill these data 

requirements for many antimicrobial pesticide chemicals. When considering biological 

properties, at this time, EPA believes that SAR and QSAR can be most effectively 

utilized in the evaluation of chemicals that exhibit lower toxicity for human health and/or 

ecotoxicity parameters. This is appropriate because the risk assessment for lower toxicity 

chemicals can be stream-lined, i.e., a screening-level assessment procedure rather than 

multiple tiers of assessments with progressively more data requirements. 

If stakeholders believe that submission of predicted data can fulfill one of the data 

needs for terbuthylazine, then the Agency invites submission of this information. The 

submitter would be expected to supply a rationale describing the utility of the information 

and provide documentation on the scientific validity of the information. The 

determination that the predicted data fulfills the data requirement would be at the sole 

discretion of the Agency. Pre-submission consultation with the Agency is encouraged. 

Endocrine Disruptor Screening Program 

As required under FFDCA section 408(p), EPA has developed the Endocrine 

Disruptor Screening Program (EDSP) to determine whether certain substances (including 

pesticide active and other ingredients) may have an effect in humans or wildlife similar to 

an effect produced by a “naturally occurring estrogen, or other such endocrine effects as 

the Administrator may designate.” The EDSP employs a two-tiered approach to making 

the statutorily required determinations. Tier 1 consists of a battery of 11 screening assays 

to identify the potential of a chemical substance to interact with the estrogen, androgen, 

or thyroid (E, A, or T) hormonal systems. Chemicals that go through Tier 1 screening 

and are found to have the potential to interact with E, A, or T hormonal systems will 

proceed to the next stage of the EDSP where EPA will determine which, if any, of the 

Tier 2 tests are necessary based on the available data. Tier 2 testing is designed to 

identify any adverse endocrine related effects caused by the substance, and establish a 

dose-response relationship between the dose and the E, A, or T effect. 

Between October 2009 and February 2010, EPA issued test orders/data call-ins 

for the first group of 67 chemicals, which contains 58 pesticide active ingredients and 9 

inert ingredients. This list of chemicals was selected based on the potential for human 

exposure through pathways such as food and water, residential activity, and certain postapplication agricultural scenarios. This list should not be construed as a list of known or 

likely endocrine disruptors. 

Terbuthylazine is not among the group of 58 pesticide active ingredients on the 

initial list to be screened under the EDSP. Under FFDCA sec. 408(p) the Agency must 

screen all pesticide chemicals. Accordingly, EPA anticipates issuing future EDSP test 

orders/data call-ins for Registration Review cases, including those for which EPA has 

already opened a Registration Review docket for a pesticide active ingredient. 

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

list of 67 chemicals, the test guidelines and the Tier 1 screening battery, please visit our 

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

Additional Information 

Stakeholders are also specifically asked to provide available information and data 

that will assist the Agency in refining the ecological and human health risk assessments. 

The Agency is interested in obtaining the following information regarding the use of 

terbuthylazine: 

1. Confirmation on the following label information: 

a. Sites of application 

b. Formulations 

c. Application methods and equipment 

d. Maximum application rates 

e. Frequency of application, application intervals and maximum 

number of applications 

f. Geographic limitations on use 

2. Use or potential use distribution 

3. Use history 

4. Usage/use information for non-agricultural uses (e.g., materials 

preservation) 

5. Typical application interval 

6. State or local use restrictions 

7. Ecological incidents (non-target plant damage and avian, fish, 

reptilian, amphibian and mammalian mortalities) not already reported 

to the Agency 

8. Monitoring data 

9. Structure Activity Relationships 

Next Steps:

After the 60-day comment period closes, the Agency will review and respond to any 

comments received in a timely manner, and then issue a Final Work Plan for 

terbuthylazine. 

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II. FACT SHEET 

Background Information

• Chemical Name: terbuthylazine 

• Registration review case number: 2645 

• PC Code: 080814 

• CAS#: 5915-41-3 

• Technical registrant: BWA Water Additives 

• First approved for use in a registered product: 1975 

• RED issued in 1995 

• Four registered products contain terbuthylazine as an active ingredient 

• Antimicrobials Division Chemical Review Manager (CRM): Eliza Blair, 

blair.eliza@epa.gov

• Antimicrobial Division Product Manager: Marshall Swindell, 

swindell.marshall@epa.gov

Chemical Structure:

Use & Usage Information

• First registered as an herbicide for use on corn fodder and forage, corn grain 

(popcorn grain included), sorghum forage and grain; food-use tolerances were 

established for these use sites and then revoked in 1992 when these uses were 

canceled. 

• Now registered for use solely in industrial recirculating cooling water systems and 

ornamental fountains. 

• Personal protective equipment required by the label in the event the product needs 

to be handled include a long-sleeved shirt, long pants, socks and shoes, chemicalresistant gloves, and the availability of a chemical-resistant apron in the event of a 

spill. 

• Application of currently-registered products is restricted to closed-system loading. 

Open pouring is prohibited. 

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Recent Regulatory Actions

 There have been no recent regulatory actions regarding the chemical 

terbuthylazine. 

Human Health Risk Assessment Status

The Agency has reviewed the human health exposure and toxicity database for the 

terbuthylazine case and anticipates that no additional exposure and toxicity data will be 

needed for registration review. 

Further information is available in Further information is available in Summary 

of Human Health Effects Data for the Terbuthylazine Registration Review Decision 

Document, dated July 19, 2010. 

Product Chemistry Database Status

The Agency has reviewed the product chemistry database for the terbuthylazine 

registration review case and anticipates that no additional product chemistry data will be 

needed for registration review. 

Further information and is available in “Terbuthylazine: Product Chemistry / 

Environmental Fate and Eco-Effects Scoping Document”, dated July 28, 2010 . 

Environmental Fate & Ecological Risk Assessment Status

 The Agency has reviewed the environmental fate and ecotoxicity databases for 

the terbuthylazine case and anticipates needing additional environmental fate and 

ecotoxicity data for the registration review of this chemical. 

The Agency has not conducted a risk assessment that supports a complete 

endangered species determination for terbuthylazine. The ecological risk assessment 

planned during registration review will allow the Agency to determine whether 

terbuthylazine use has “no effect” or “may affect” federally listed threatened or 

endangered species (listed species) or their designated critical habitats. When an 

assessment concludes that a pesticide’s use “may affect” a listed species or its designated 

critical habitat, the Agency will consult with the U.S. Fish and Wildlife Service and/or 

National Marine Fisheries Services (the Services), as appropriate. 

Further information and detailed justifications for the studies that are anticipated 

as being needed are available in “Terbuthylazine: Product Chemistry / Environmental 

Fate and Eco-Effects Scoping Document”, dated July 28, 2010 . 

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Tolerances 

 There are no current tolerances or exemptions from tolerances for the 

terbuthylazine active ingredient and no registered food uses. 

Data Call-In Status

 

A RED was issued for terbuthylazine in 1995. A Generic Data Call-In (GDCI) 

was issued in 1995 (data requirements satisfied). A Product-Specific Data Call-In 

(PDCI) was also issued in 1995 (data requirements satisfied). The Agency anticipates 

needing additional data to complete a risk assessment during Registration Review. 

Labels 

There are four products registered for terbuthylazine. The EPA Registration 

Number is provided in Table 1 below. Product registration labels may be obtained from 

the Pesticide Product Label System (PPLS) website at: 

http://oaspub.epa.gov/pestlabl/ppls.home. 

Table 1. Registered products containing Terbuthylazine 

EPA Reg. 

No. 

Product Name Formulation 

Type 

Percent Active 

Ingredient 

Registrant 

83451-7 Bellacide 320 MUP 96 BWA Water 

Additives US, 

LLC 

9386-34 AMA-204 Aqueous 

Dispersion 

4.0 Kemira 

Chemicals, Inc 

83451-8 Bellacide 329 Aqueous 

Dispersion 

44.7 BWA Water 

Additives US, 

LLC 

83451-9 Bellacide 325 Aqueous 

Dispersion 

4.0 BWA Water 

Additives US, 

LLC 

Incidents

 A search of OPP’s Incident Database System (IDS) revealed two incidents 

connected to terbuthylazine. No further information was available regarding these 

incidents. 

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III. GLOSSARY of TERMS & ABBREVIATIONS

ai Active Ingredient 

AR Anticipated Residue 

ASTM American Society for Testing and Materials 

AWPA American Wood Preserver’s Association 

CFR Code of Federal Regulations 

cPAD Chronic Population Adjusted Dose 

CSF Confidential Statement of Formula 

CSFII USDA Continuing Surveys for Food Intake by Individuals 

DCI Data Call-In 

DEEM Dietary Exposure Evaluation Model 

DFR Dislodgeable Foliar Residue 

DNT Developmental Neurotoxicity 

DWLOC Drinking Water Level of Comparison 

EC Emulsifiable Concentrate Formulation 

EDWC Estimated Drinking Water Concentration 

EEC Estimated Environmental Concentration 

EPA Environmental Protection Agency 

EUP End-Use Product 

FDA Food and Drug Administration 

FIFRA Federal Insecticide, Fungicide, and Rodenticide Act 

FFDCA Federal Food, Drug, and Cosmetic Act 

FQPA Food Quality Protection Act 

FOB Functional Observation Battery 

GENEEC Tier I Surface Water Computer Model 

IR Index Reservoir 

LC50 Median Lethal Concentration. A statistically derived concentration of a 

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

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

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

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

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

(oral, dermal, inhalation). It is expressed as a weight of substance per unit 

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

LOC Level of Concern 

LOAEL Lowest Observed Adverse Effect Level 

μg/g Micrograms Per Gram 

μg/L Micrograms Per Liter 

mg/kg/day Milligram Per Kilogram Per Day 

mg/L Milligrams Per Liter 

MOE Margin of Exposure 

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

submitted studies. 

MUP Manufacturing-Use Product 

NA Not Applicable 

NAWQA USGS National Ambient Water Quality Assessment 

NPDES National Pollutant Discharge Elimination System 

NR Not Required 

NOAEL No Observed Adverse Effect Level 

OPP EPA Office of Pesticide Programs 

OPPTS EPA Office of Prevention, Pesticides and Toxic Substances 

PAD Population Adjusted Dose 

PAIRA Pure Active Ingredient Radiolabelled 

PCA Percent Crop Area 

PDP USDA Pesticide Data Program 

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PHED Pesticide Handler's Exposure Data 

PHI Preharvest Interval 

ppb Parts Per Billion 

PPE Personal Protective Equipment 

ppm Parts Per Million 

PRZM/EXAMS Tier II Surface Water Computer Model 

Q1* The Carcinogenic Potential of a Compound, Quantified by the EPA's Cancer 

Risk Model 

RAC Raw Agriculture Commodity 

RED Reregistration Eligibility Decision 

REI Restricted Entry Interval 

RfD Reference Dose 

RQ Risk Quotient 

SCI-GROW Tier I Ground Water Computer Model 

SAP Science Advisory Panel 

SF Safety Factor 

SLN Special Local Need (Registrations Under Section 24©) of FIFRA) 

TGAI Technical Grade Active Ingredient 

TEP Typical End-Use Product 

USDA United States Department of Agriculture 

UF Uncertainty Factor 

WPS Worker Protection Standard 
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IV. Appendix A

Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use L

Industrial processes and water systemOps Industrial recirculation water cooling systems 

Soluble Concentrate: 83451-8 83451-9 Technical: 83451-7 Ready-to-Use Solution: 9386-34 

Incorporation Continuous feed method Intermittent or Slug method Continuous feed method 

Chlorinated and/or 

Brominated Systems(i) Continuous Addition: Maintain up to 2.5 fluid oz / 10,000 gallons of water (~2 ppm) (ii) Slug/Intermittent addition: maintain up to 2 ppm concentration. Non-Chlorinated and/or Brominated systems, both continuous and slug/intermittent dose

Maintain up to 8 fluid oz. / 10,000 gallons of water (~6.7 ppm) Chlorinated and/or 

Brominated systems(i) Continuous Addition: maintain up to 3 fluid oz. / 

Open pouring of thiMixing, loading, ana closed system (onchemical from contpersons) and during personal protective Personal protective sleeved shirt, long pchemical-resistant gresistant apron must during loading and worn in case of a leto the concentrate. Do not use in coolinwhere the treated wwith lawns, trees, shplants. Water from tbe used for irrigationor for watering livconsumption. 

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Use Site Formulation Method of 

Application 

Application Rate/ No. of 

applications 

Use L

Intermittent or Slug method 

1,000 gallons of water (~25 ppm) (ii) Slug/Intermittent Addition: Apply sufficient product to maintain up to 25 ppm of product in system water Non-Chlorinated and/or Brominated systemsMaintain up to 9 fluid oz. / 1,000 gallons of water (~75 ppm) via continuous or slug/intermittent dosing as described above. 

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www.regulations.govDecorative/Ornamental Fountains (Indoor) Ornamental fountains Soluble 

Concentrate: 83451-8 83451-9 Technical: 83451-7 Ready-to-Use Solution: 9386-34 

Incorporation Continuous feed method Intermittent or Slug method 

Chlorinated and/or 

Brominated Systems(i) Continuous Addition: Maintain up to 2.5 fluid oz / 10,000 gallons of water (~2 ppm) (ii) Slug/Intermittent addition: maintain up to 2 ppm concentration. Non-Chlorinated and/or Brominated systems, both continuous and slug/intermittent dose

Maintain up to 8 fluid oz. / 10,000 gallons of water (~6.7 ppm) Chlorinated and/or 

Brominated systems(i) Continuous Addition: maintain up to 3 fluid oz. / 1,000 gallons of water (~25 ppm) (ii) Slug/Intermittent 

Open pouring of thiMixing, loading, ana closed system (onchemical from contpersons) and during personal protective Personal protective sleeved shirt, long pchemical-resistant gresistant apron must during loading and worn in case of a leto the concentrate. Do not use in coolinwhere the treated wwith lawns, trees, shplants. Water from tbe used for irrigationor for watering livconsumption. 

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Addition: Apply sufficient product to maintain up to 25 ppm of product in system water Non-Chlorinated and/or 

Brominated systemsMaintain up to 9 fluid oz. / 1,000 gallons of water (~75 ppm) via continuous or slug/intermittent dosing as described above.