Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 2 of 22 Homopolymer Registration Review Team

Human Health & Environmental Effects Siroos Mostaghimi Jim Breithaupt David Bays Jonathan Chen
Nate Mottl Katelynn King

Risk Management Donna Kamarei Rose Kyprianou

Office of General Counsel Philip RossDocket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 3 of 22 TERMS, ABBREVIATIONS AND SYMBOLS

AD Antimicrobials Division A.I. or a.i. active ingredient ASRI activated sludge respiration inhibition CAS Chemical Abstracts Service CFR Code of Federal Regulations CMA Chemical Manufacturers Association COC concentration-of-concern EC 50 median (or 50 percent) effect concentration ECOTOX ECOTOXicology EDSP Endocrine Disruptor Screening Program E-FAST Exposure and Fate Assessment Screening Tool EPA Environmental Protection Agency FDA Food and Drug Administration FFDCA Federal Food, Dr ug, and Cosmetic Act FIFRA Federal Insecticide, Fungicide, and Rodenticide Act FQPA Food Quality Protection Act HPV high production volume IDS Incident Data System Kow octanol-water partition coefficient LC 50 median (or 50 percent) lethal concentration LD 50 median (or 50 percent) lethal dose Log K ow logarithm of the octanol-water partition coefficient μg microgram mg/kg milligram per kilogram mg/L milligram per liter mm Hg millimeter of mercury MRID Master Record Identification Number MRL maximum residue limit N/A not applicable
nm nanometers NOAEC no-observed-adverse-effect-concentration OCSPP Office of Chemical Safety and Pollution Prevention OPP Office of Pesticide Programs % percent PC Code Pesticide Chemical Code pKa power of the acid dissociation constant or negative base-10 logarithm of the acid dissociation constant of a solution ppb parts per billion ppm parts per million PWP Preliminary Work Plan RED Reregistration Eligibility Decision SSTS Section Seven Tracking System TGAI technical grade active ingredient TMDL total maximum daily loads UV/VIS ultraviolet/visible light absorption WWTPs wastewater treatment plantsDocket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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### Table of Contents

1 Introduction .................................................................................................................. ........... 6 1.1 Statutory and Regulatory Authority ................................................................................. 6 1.2 Case Overview ................................................................................................................. 7 1.3 Chemical Identification and Properties ............................................................................ 7 1.4 Use/Usage Description ..................................................................................................... 9 1.4.1 Registrations ............................................................................................................. 9 1.4.2 Summary of Regist ered Uses .................................................................................... 9 1.4.3 Usage Information .................................................................................................... 9 1.5 Regulatory History ........................................................................................................... 9 1.5.1 Recent/Pending Regulatory Actions ....................................................................... 10 1.5.2 Tolerance Information ............................................................................................ 10 1.6 Incidents ..................................................................................................................... .... 10 1.6.1 Human Health ......................................................................................................... 10 1.6.2 Ecological ............................................................................................................... 10 2 Anticipated Data Needs ........................................................................................................ 10 3 Human Health Risk Assessment ........................................................................................... 10 3.1 Existing Toxicological Endpoints .................................................................................. 10 3.2 Dietary Exposure ............................................................................................................ 1 1 3.2.1 Food and Drinking Water ....................................................................................... 11 3.3 Occupational and Residential Exposures ....................................................................... 11 3.4 Aggregate and Cumulative Exposure ............................................................................. 11 3.4.1 Aggregate Exposures .............................................................................................. 11 3.4.2 Cumulative Exposures ............................................................................................ 11 4 Environmental Risk Assessment........................................................................................... 12 4.1 Threatened and Endangered Species .............................................................................. 12 4.2 Environmental Fate Assessment .................................................................................... 12 4.2.1 Water Quality .......................................................................................................... 13 4.3 Conceptual Models for Envir onmental Exposure Pathways .......................................... 13 4.4 Ecological Effects Assessment ....................................................................................... 13 4.4.1 Measures of Effect (Ecotoxicology Endpoints) ...................................................... 13 4.5 Exposure Analysis Plan .................................................................................................. 13 4.5.1 Aquatic and Terrestrial Wild life Exposure Estimates ............................................ 13 4.5.2 Screening Level Down-the-Drain Analysis ............................................................ 14 5 Endocrine Disruptor Screen ing Program (EDSP) ................................................................. 14 6 Interim Registration Review Decision .................................................................................. 15 7 Next Steps .................................................................................................................... ......... 15 8 References .................................................................................................................... ......... 16

Appendix A Toxicology Profile ............................................................................................... 17 Appendix B Environmental Fate ............................................................................................. 20 Appendix C Ecotoxicology Profile .......................................................................................... 21Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 5 of 22 List of Tables Table 1 – Summary of Anticipated Risk Assessments and Data Needs for Registration Review: Homopolymer ................................................................................................................... .............. 7 Table 2 – Anticipated Regist ration Review Schedule .................................................................... 7 Table 3 – Chemical Identification of Homopolymer ...................................................................... 8 Table 4 – Physical-Chemical and Environmental Fate Properties for Homopolymer .................... 8 Table 5 – Homopolymer Registered Use ........................................................................................ 9 Table 6 – Acute Toxicity Studies for Homopolymer.................................................................... 17 Table 7 – Freshwater Fish and Amphibian Toxicity Data ............................................................ 21 Table 8 – Freshwater Invert ebrate Toxicity Data ......................................................................... 21Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 1 Introduction

This document is the Environm ental Protection Agency’s (EPA or “the agency”) Interim Registration Review Decision fo r 2-Propen-1-aminium, N,N-dime thyl-N-2-propenyl-, chloride, homopolymer herein referred to as homopolym er, and is being issued pursuant to 40 CFR Sections 155.50, 155.56 and 155.58. This document expl ains what EPA’s Office of Pesticide Programs knows about homopolymer , noting that no additional data nor further assessments are required, and provides an anticipated timelin e for completing homopolymer’s review.

A registration review decision is the agency's determination whether a pesticide meets, or does not meet, the standard for registration in the Fe deral Insecticide, Fungicide, and Rodenticide Act (FIFRA). The agency may issue, when it determin es it to be appropriate, an interim registration review decision before comple ting a registration review. Am ong other things, the interim registration review decision may require new ri sk mitigation measures, impose interim risk mitigation measures, identify data or information required to complete the review, and include schedules for submitting the required data, conduc ting the new risk assessment and completing the registration review.

The Proposed Interim Registration Review D ecision for homopolymer was issued for public comment on August 10, 2015 and the comment peri od closed on October 9, 2015. During the 60- day public comment period, no comments were rece ived concerning the registration review of homopolymer. As a result, no changes were made to the document.



## 1.1 Statutory and Regu latory Authority
The Food Quality Protection Act (FQPA) of 1996 mandated a regi stration review program. All pesticides distributed or sold in the United St ates generally must be registered by the USEPA based on scientific data showing that they will not cause unreasonable risk s to human health or the environment when used as directed on produc t labeling. The registra tion 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 environm ent. Changes in scien ce, public policy, and pesticide use practices will occur over time. Th rough the registration review program, the agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely. Inform ation on this program is provided at http://www2.epa.gov/pesticide-reevaluation

. The agency is implementing the registration revi ew program pursuant to Section 3(g) of FIFRA and will review each registered pesticide every 15 years to determine whether it continues to meet the FIFRA standard for registration. The re gulations governing regist ration review begin at 40 CFR 155.40. The agency will consider benefits information and data as required by FIFRA. The public phase of registration review begins wh en the initial docket is opened for each case. The docket is the agency’s opportunity to stat e what it knows about the pesticide and what additional risk analyses and data or information it believes ar e needed to make a registration review decision.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 1.2 Case Overview
The docket for homopolymer (case # 5024) has been established at http://www.regulations.gov in docket number EPA-HQ-OPP-2015-0255. Documents associated with this registration review can be viewed in this docket. Tables 1-2 below su mmarize the issues relevant to this registration review case and the anticipated registration review schedule.

Table 1 – Summary of Anticipated Risk Asse ssments and Data Needs for Registration Review: Homopolymer

Risk Assessment Assessment Necessar y to Support Registration Review Date of Most Recent Assessment Type of Assessment Required (New/Updated) Data Anticipated as Needed

Dietary (food/ drinking water ) No N/A None None

Occupational & Residential Handler/Post Application No N/A None None

Aggregate No N/A None None

Cumulative No N/A None None

Tolerance Review No N/A None None Ecological No N/A None None
N/A = Not applicable Table 2 – Anticipated Regi stration Review Schedule

Anticipated Activity Target Date* Completion Date Combined Preliminary Wo rk Plan and Interim Registration Review Decision and Implementation Open 60-Day Public Comment Period for Combined Preliminary Work Plan and Proposed Interim Decision 2015-06 2015-08-10

Close Public Comment Period 2015-08 2015-10-09 Issue Interim Decision and Begin Post-Decision Follow up * 2015-12
Total (years) 1 * A final decision on the homopolymer registra tion review case, in acco rdance with 40 CFR Section 155.58, will occur after an EDSP FFDCA section 408(p) dete rmination has been made.



## 1.3 Chemical Identification and Properties
Table 3 presents the active ingredient to be assessed in case 5024: homopolymer (PC Code 128727). The active ingredient has one registered product with the active ingredient composing 19.8 percent (w/w).Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 8 of 22 Table 3 – Chemical Identi fication of Homopolymer

Chemical Name Homopolymer Reference (MRID unless specified) Comments Chemical Classification Polymeric quaternary ammonium PAN 1

PC Code 128727 None

CAS Number 26062-79-3 (polymer) 7398-69-8 (monomer) PAN

Molecular Formula Polymer : Not applicable Monomer : C 8 H 16 CN None

Molecular Weight (grams/mole) 200,000 (average, polymer) 161.68 (monomer) Sigma Aldrich (polymer) Epi-Web 4.1 (monomer)

Molecular Structure Hess et al., 2003

The homopolymer physical chemistry information is summarized in Table 4. The details of the environmental fate information are discussed in Appendix B.

Table 4 – Physical-Chemical and Environm ental Fate Properties for Homopolymer

Guideline No. Parameter Homopolymer (EPA Reg. No. 1706-226): Poly (dimethyldially) ammonium chloride Reference (MRID unless specified)

830.7050 UV/Visible Absorption Stable to sunlight (no conjugation in structure) Lyman et al., 1990

830.7370 Dissociation constant (pKa) Not applicable No ionizable functional groups

830.7550 Octanol-water partition coefficient at 25 o C (Log K ow ) Not applicable (substance is miscible in water) 42618401

830.7840 Solubility in water Miscible (10,000 mg/l used in calculations) 42618401

830.7950 Vapor pressure (mmHg) Polymer : None (up to 230 o C) Monomer: 15 mm Hg 42618401

None Henry’s law constant at 25 o C (atm-m 3 /mol) CALCULATED Polymer : Not applicable (polymer has wide range of molecular weights) Monomer : 3.2 x 10 -4 None

atm-m 3 /mol = atmosphere cubic meter per mole; o C = degrees Celsius; mg/L = milligrams per liter; mmHg = millimeters of mercury.

1 http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC35969Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 1.4 Use/Usage Description

1.4.1 Registrations
There is one EPA-registered product containing homopolymer as an activ e ingredient (a.i.). 2 It contains 19.8 percent homopolymer in a liquid soluble concentrate formulation.



### 1.4.2 Summary of Registered Uses

Table 5 presents the registered use of homopolym er as mollusk control (e.g. Zebra mussels) in potable water supplies. The product is added to water systems as a concentrated liquid using metered pumps. The label states th at applications should occur at a point sufficiently inside the intake pipe to prevent any releas e of product into the in take source (5-10 feet). Feed exits must be equipped with a pressure check valve at the feed line exit to seal the f eed line when the intake flow stops. Feed pumps must be designed to shut down when intake pumps stop. Planned shutdowns require feed pumps to be stoppe d half an hour prior to shut down.

Table 5 – Homopolymer Registered Use

Use Application Method Application Rate (ppm a.i.)
Industrial Process and Water Systems
Water supplies Metered Pump 25-50



### 1.4.3 Usage Information

In addition to its use as a pesticide, homopolym er is used as a floccu lant in drinking water treatment. Based on information provided by the regi strant, the pesticidal use of homopolymer is minor when compared to the non-pesticidal use. According to the 2004 high production volume test plan, homopolymer has been manufactured for at least 40 years in the United States with three current manufacturing fac ilities. The monomer is used almost exclusively in the manufacturing of cationic, water-soluble polymer s which are used in such industries as water treatment plants, paper mills, and textile printing. Using Best Available Technology (BAT) to achieve maximum efficacy, the maximum free mono mer content of the polymeric products is about 1 percent. 3



## 1.5 Regulatory History

The first product containing homopolymer was re gistered on October 6, 1995 for the use in industrial process and water systems. A Reregi stration Eligibility De cision (RED) was not completed for homopolymer because it wa s registered after November 1, 1984.

2 Veligon TL-M, EPA Reg. No. 1706-226

3 Regnet Environmental ServicesDocket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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### 1.5.1 Recent/Pending Regulatory Actions

There are no recent regulatory actions for homopolymer.



### 1.5.2 Tolerance Information

There are no EPA-established tolerances in ra w agricultural commodities or processed food and feed products for homopolymer under the Federal Food, Drug and Cosmetic Act (FFDCA) Sections 408. Additionally, the Federal Food and Drug Administra tion (FDA) has not established any clearances under FFDCA 409. However, Food Contact Notifications (FCNs) have been established for homopolymer as part of various polymers. Since these uses are not FIFRAregistered, no dietary exposur e assessment is required.



## 1.6 Incidents

1.6.1 Human Health

No homopolymer related incidents have been repo rted in the agency’s Incident Data System (IDS) for the time period from 1992 to presen t, based on a search conducted on March 2015. IDS contains reports of incidents from various source s, including registrants, other federal and state health and environmental agencies and indi vidual consumers, submitted to OPP since 1992.



### 1.6.2 Ecological
No homopolymer incidents have been reported in the agency’s Ecological Incident Information System (EIIS) for the time period spanning 2000 to 2015 based on a search conducted on April 15, 2015.



## 2 Anticipated Data Needs

The agency does not anticipate re quiring any additional data to support this registration review.



## 3 Human Health Risk Assessment

With the existing toxicology database, homopolymer appears to have low toxicity (Appendix A). The use of homopolymer as a water treatment for control of mollusks in water supplies is not expected to pose a hazard to food or drinki ng water based on the lack of exposure. The application system is closed and there is no expected occupational exposure. The agency does not anticipate the need to conduct a human health risk assessme nt for homopolymer.



## 3.1 Existing Toxicological Endpoints

No toxicological endpoints have been selected for homopolymer.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 3.2 Dietary Exposure

The agency does not anticipate the need to c onduct a dietary exposure as sessment to support this registration review.



### 3.2.1 Food and Drinking Water
A dietary (food and drinking wate r) exposure assessment is not required for homopolymer. The only FIFRA-registered use of homopolymer is as a water treatment for the control of mollusks in water supplies. There is only one label use for this product, and this use is not expected to result in direct or indirect dietary (food) exposure. The use of homopol ymer as a water treatment for the control of mollusks in water supplies is not expected to result in e xposure from groundwater or surface waters; therefore, a drinking water assessment is not required.



## 3.3 Occupational and Re sidential Exposures
In April of 2015, the registrant amended its labe l to restrict applica tion to closed metered delivery systems; open pouring is prohibited for water treatment. Occupational handler exposures are not expected due to closed mixi ng/loading. Dermal and inhalation post-application exposures for the water treatment uses are exp ected to result in limite d exposure contact. No additional occupational exposure da ta or occupational risk assessm ents are anticipated to be required. No residential exposure is expected since applications are only performed in occupational settings.



## 3.4 Aggregate and Cumulative Exposure

3.4.1 Aggregate Exposures

An aggregate exposure risk assessment will not be conducted for this chemical because of a lack of residential exposure due to its use pattern of only being ap plied in industrial pipes with restrictions for controlling backflow into surface water.



### 3.4.2 Cumulative Exposures
With respect to cumulative exposure, unlike other pesticides for which EPA has followed a cumulative risk approach based on a common me chanism of toxicity, EPA has not made a common mechanism of toxicity finding as to homopolymer and any other substances, and homopolymer does not appear to produce a toxi c metabolite produced by other substances. For the purposes of this registration review, theref ore, EPA has not assumed that homopolymer has a common mechanism of toxicity w ith other substances. For information regarding EPA’s efforts to determine which chemicals have a common me chanism of toxicity and to evaluate the cumulative effects of such chemicals, see http://www2.epa.gov/pesticid e-science-and-assessingpesticide-risks/cumulative-assessment-risk-pesticides

.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 4 Environmental Risk Assessment

The agency has not previously conducted a risk assessment that supports a complete endangered species determination for homopolymer. The label stat es that application to intake water should be made 5-10 feet away from the source water in take source to prevent contamination. Based on the use in potable water supply sy stems, the potential pathways of exposure to aquatic organisms include transport from in-service use to surface water by way of wastewater treatment plants (WWTPs) and any backflow from treated intake water. However, label restrictions prevent backflow into surface water, and the environm ental fate data indicate strong sorption to sediment.

Based on the chemical, physical, and environmental fate properties, homopolymer is miscible in water, non-volatile, and stable to hydrolysis a nd photodegradation. Enviro nmental fate data are not anticipated to be required (Table 4 a nd Appendix B). The acceptable activated sludge respiration inhibition (ASRI) study (MRID 49437513) demonstrated an IC50 of 127 mg/L (>20 mg/L) indicating negligible effects on WWTP organisms. 4 While data on sorption to soil and sediment (835.1230) have not been submitted, the agency considers drinking water exposure to be negligible because, as a quaternary amm onium polymer, homopolymer will attach to suspended sediments and organic matter and will be removed by flocculation and coagulation of suspended particles in source water. Floccula nts work by reducing or neutralizing negative charges on suspended particles, allowing them to associate and settle in the treatment process. 5 If any particles with sorbed homopolymer are rede posited into surface water, homopolymer is not expected to desorb and enter the water colu mn. The agency does not intend to conduct an environmental risk assessment because label restri ctions prevent backflow into surface water.



## 4.1 Threatened and Endangered Species

There is no reasonable expectation for the regist ered use of homopolymer to cause direct or indirect adverse effects to threatened and enda ngered species. No adverse modification of any designated critical habitat for such species is expected from the use of homopolymer. Exposure of terrestrial species is unlikely, because label restrictions prevent backflow into surface water, and the environmental fate data indicate strong sorption to sediment. EPA has made a “no effect” determination under the Endangered Species Act (ESA) for all listed species and designated critical habitat for such species and has therefor e concluded that consulta tion with the Fish and Wildlife Service and the National Marine Fisher ies Service under ESA section 7(a)(2) is not required.



## 4.2 Environmental Fate Assessment
Based on the chemical, physical, and environmental fate properties, homopolymer is miscible in water, non-volatile, and stable to hydrolysis a nd photodegradation (Table 4 and Appendix B).

4 Breithaupt, James; D427116, Re viewed and accepted on May 5, 2015

5 CIBA, http://www.siltstop.com/pdf/flocculation-theory_application.pdfDocket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 13 of 22 Additional environmental fate data are not requir ed because backflow into surface water is not expected to occur based on the use dir ections specified on the label.



### 4.2.1 Water Quality
Homopolymer is not identified as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Water Act. 6 In addition, no Total Maximum Daily Loads (TMDL) have been developed for homopolymer. 7 More information on impaired water bodies and TMDLs can be found at EPA’s website. 8



## 4.3 Conceptual Models for Enviro nmental Exposure Pathways

The only environmental exposure pathway for the pesticidal use of homopolymer is one of potential backflow into the surface water used as source water. As a mitigation measure, the labels state that application to intake water should be made 5-10 feet away from the source water intake source to prevent contamination. As a re sult, the agency assumes that no environmental exposure will occur and therefor e is not including conceptu al models for exposure.



## 4.4 Ecological Effects Assessment
An ecological effects risk assessment is not requ ired for this chemical because of a lack of exposure to non-target organisms due to its rest ricted use pattern of only being applied in industrial pipes with rest rictions for controlling backflow into surface water.



### 4.4.1 Measures of Effect (Ecotoxicology Endpoints)

Ecotoxicity endpoint data are used as measures of effects to aqua tic and terrestrial organisms. Selected endpoints are not necessary for this chemical because an environmental risk assessment is not necessary. There were six ecotoxicity st udies submitted to the agency as a condition of registration for two chemicals c ontaining homopolymer as an activ e ingredient. These studies are outlined in Appendix C.



## 4.5 Exposure Analysis Plan

4.5.1 Aquatic and Terrestrial Wildlife Exposure Estimates

The agency does not need to conduct an ecological risk assessment because of negligible environmental exposure based on the label language to prevent backflow from intake pipes and the strong tendency of homopolymer to sorb to ne gatively-charged particle s in intake water.

6 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885

7 http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl _pollutant_detail?p_pollutant_group_id=885&p_pollutant_ group_name=PESTICIDES

8 http://www.epa.gov/owow/tmdl/Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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### 4.5.2 Screening Level Down-the-Drain Analysis
The Down-the-Drain (DtD) module of E-FAST (E xposure and Fate Assessment Screening Tool) was not used to assess homopolymer since the compound is a strong flocculant which would be removed prior to a wastewater treatment plant.



## 5 Endocrine Disruptor Screening Program (EDSP)

As required by FIFRA and FFDCA, EPA reviews num erous studies to asse ss potential adverse outcomes from exposure to chemicals. Collectiv ely, these studies includ e acute, subchronic and chronic toxicity, including asse ssments of carcinogenicity, ne urotoxicity, developmental, reproductive, and general or systemic toxicity. These studies include e ndpoints which may be susceptible to endocrine influe nce, including effects on endocri ne target organ histopathology, organ weights, estrus cyclicity, sexual maturatio n, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess gr owth, developmental and reprod uctive effects in different taxonomic groups. As part of its most recen t registration decision, for homopolymer, EPA reviewed these data and select ed the most sensitive endpoints for relevant risk assessment scenarios from the existing hazard database. However, as required by FFDCA section 408(p), homopolymer is subject to the endocrin e screening part of the E ndocrine Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whet her 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 ot her such endocrine effect s as the Administrator may designate.” The EDSP employs a two-tiered approach to making th e 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 estrog en, androgen, or thyroid (E, A, or T) hormonal systems. Chemicals that go th rough Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stag e of the EDSP where EPA will determine which, if any, of th e Tier 2 tests are necessary base d on the available data. Tier 2 testing is designed to identify a ny adverse endocrine-related eff ects 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 scr een all pesticide chemicals. Between October 2009 and February 2010, EPA issued test orders/dat a call-ins for the firs t group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredient s. A second list of chemicals identified for EDSP screening was published on June 14, 2013 9 and includes some pesticides scheduled for registration review and chemicals found in water

. Neither of these lists should be construed as a list of known or lik ely endocrine disruptors. For fu rther information on the status of the EDSP, the policies and proced ures, the lists of chemicals, fu ture lists, the test guidelines and the Tier 1 screening batte ry, please visit our website. 10

9 See http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPPT-2009-0477-0074 for the final second list of

chemicals.

10 http://www2.epa.gov/endocrine-disruptionDocket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 6 Interim Registration Review Decision

In accordance with 40 CFR Sections 155.50, 155.56 and 155.58, the agency is issuing this Interim Registration Review Decision docum ent. Except for the EDSP component of the homopolymer registration review case, the agency has made the following interim decision that no additional data and no further risk assessmen ts are required. Based on the assumption of no exposure to humans and non-target organisms, no additional data are needed and no risk assessments are planned. The agency has made a “no effect” finding based on lack of potential exposure for endangered speci es (see Section 4.1).



## 7 Next Steps

A Federal Register Notice will announce the availa bility of this Interim Registration Review Decision for homopolymer. The final decision on the registration review for homopolymer (case 5024) will occur after an EDSP FFDCA section 408(p) determination is made. See the estimated timeline for the completion of homopolymer registration review in Table 2.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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## 8 References

Breithaupt, James. May 5, 2015. Review of M odified Activated Sludge Respiration Inhibition Study (OCSPP 850.3300) for Homopolymer. MRID 49437513, D427116

Ciba (year unknown). Flocculati on Theory and Application. http://www.siltstop.com/pdf/flo cculation-theory_application.pdf

Hess, C.E., Naik, K.N., Paquin, T.J., and Rose, S.J. February 27, 2003. Topcoat compositions, substrates containing a topcoat derived ther efrom, and methods of preparing the same. Publication Number: WO2003016045 A1, Application Number: PCT/US2002/026136. http://www.google.com/patents/WO2003016045A1?cl=en

MRID 42618401. Oslosky, S. (1992) Product Chem istry: Poly (N,N-dimethyl diallyl ammonium chloride): Lab Project Number : DMDAAC. Unpublished study prepared by Calgon Corporation. 8 p.

Park, S.H. April, 2008. Effect of Amine-Base d Water Treatment Polymers on the Formation of N-Nitrosodimethylamine (NDMA) Disinfection By-Product. Georgia Institute of Technology. https://smartech.gatech.edu/bits tream/handle/1853/ 22549/park_sanghyuck_200805_phd. pdf?sequence=1

Pesticide Action Network (PAN). 2014. Dially l dimethyl ammonium chloride polymers. http://www.pesticideinfo.org/De tail_Chemical.jsp?Rec_Id=PC35969

Regnet Environmental Services. April 29, 2004. Test Plan for Diallyldimethylammonium Chloride (DADMAC): CAS N o. 7398-69-8. EPA 201-15208A. http://www.epa.gov/chemrtk/pubs/summaries/dialdime/c15208tp.pdf

Sigma Aldrich Online Catalog. 2014. http://www.sigmaaldrich.com/life-science/life-sciencecatalog.html

U.S. Environmental Protection Agency (E PA). 2002. ECOTOX User Guide: ECOTOXicology Database System. Version 3.0. Available: http://www.epa.gov/ecotox/

U.S. Environmental Protection Agency (EPA). 2012. EPI-Suite 4.11. http://www.epa.gov/oppt/exposur e/pubs/episuitedl.htm

U.S. Environmental Protection Agency. High Pr oduction Volume Information System (HPVIS). http://www.epa.gov/hpvis/Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

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# Appendix A Toxicology Profile

Acute Toxicity for Product Labeling

As listed in Table 6, homopolymer is a moderate de rmal irritant (Category III) and is in Category III for acute oral toxicity and Ca tegory IV for acute dermal toxici ty based on guideline studies. It is likely a moderate eye irritant (Category III). However, guidelin e acute studies are not available for acute inhalation acute eye irrita tion and dermal sensitization.

Table 6 – Acute Toxicity Studies for Homopolymer

Guideline No./ Study Type MRID No. Results Toxicity Category
870.1100/ Acute oral toxicity 42534004 LD50 = 4,100 mg/kg for male and female rat III

870.1200/ Acute dermal toxicity 42534005 LD50 ≥ 20,000 mg/kg for male and female rabbit IV

870.1300/ Acute inhalation toxicity NA No acceptable Guideline study. Th is study is considered as a data gap. Unknown

870.2400/ Acute eye irritation 42534006 Eye irritation at 24 hours after treatment and clearing in 7 days. III

870.2500/ Acute dermal irritation 42534007 Moderate irritation at 72 hours on New Zealand Albino Rabbits III

Note: N/A=Not available 

## Subchronic Toxicity

For subchronic oral toxicity, the database includes four studies:

 Roper, J.M. (2009) A 90-day oral (drinking water) toxic ity study of 2-Methyl-1,2- benzisothiazolin-3-one Technical in rats. WIL Research Laboratories, LLC, Ashland, OH, USA.WIL-91057, November 9, 2009. MRID 48251534. Unpublished.

 Trautwein and Drommer. (1976). 13 Weeks Or al Toxicity Feeding Study with Monomer in Rats. International Bi o-Research, Inc. Unpublished.

 Trautwein and Drommer. (1976). 13 Weeks Or al Toxicity Feeding Study with Cat FlocT in Rats. International Bi o-Research, Inc. Unpublished.

 Tegeris, A.S. (1976). DADM – Ninety-Day Feeding Study to Dogs. Pharmacopathics Research Laboratories, Inc. Laurel, MD . 20810. Sponsored Report No. 76-57. July 2, 1976. Unpublished.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 18 of 22 

## Developmental Toxicity

 Adamik, E. R. (1979). Rabbit Teratology Study with Cat-Floe T. Wil Research Laboratories, Inc. Cincinnati, OH 45241. November 29, 1979. MRID 42534016. Unpublished.

 Irvine, L.F.H. and Palmer, K. (1990). Poly(Dimethyl Diallyl Ammonium Chloride) (PDADMAC) Oral (Gavage) Rat Teratol ogy Study. Toxicol Laboratories Limited. Herefordshire, England HR8 lLH . Laborator y Project ID CMA/5/ 91. November 9, 1991. MRID 48437511. Unpublished.


## Reproductive Toxicity

 Adamik, E. R. (1979). Multigeneration Study in Rats with Cat-Floe T. Wil Research Laboratories, Inc. Cincinnati, OH 45241. Laboratory Project ID WIL-1140-77. November 29, 1979. MRID 49437512. Unpublished.


## Chronic Toxicity There is currently no existing chronic toxicity st udy for homopolymer. Since there is no chronic exposure concern, this is not considered as a data gap.


## Carcinogenicity There is currently no exis ting cancer study for homopolymer . Since there are existing mutagenicity studies indicating homopolymer is not mutagenic, th e absence of a cancer study is not considered as a data gap.


## Neurotoxicity There is no neurotoxicity study in the database for homopolymer.


## Mutagenicity

1. Sun, R.H.C. and Shelton, J.B. (1990) . Selmonella/Mammalian-Microsome Plate Incorporation Mutagenicity Assay (Amen Test) - Poly (dtaiiyldimethyl ammonium chloride). Microbiological Associat es, Inc., Rockville, MD 20850. June 21, 1990. MRID 42534013. Unpublished.

2. Putman, D.L. (1990). Micronucle us Cytogenetic Assay in Mi ce - Poly (dtaiiyldimethyl ammonium chloride). Microbiological A ssociates, Inc., Rockville, MD 20850. June 21, 1990. MRID 42534014. Unpublished

3. Putman, D.L. (1991). Micronuc leus Cytogenctic Assay in Mice. Microbiological Associates. Inc. Bethesda, MD 20816. Laboratory Project ID T9143.122. March 27, 1991. MRID 49437510. Unpublished.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 19 of 22 

## Dermal Absorption/Penetration

There is no dermal absorption study in the data base. However, since homopolymer is applied through closed system, there is no occupational exposure.


## Immuntoxicity There is currently no existing immunotoxicity st udy for homopolymer. Howe ver, since there is no exposure concern, immunotoxicity study is not considered as a data gap.



## Metabolism There is no metabolism study available. However, since there is no exposure concern, the absence of a metabolism study is no t considered as a data gap.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 20 of 22



# Appendix B Environmental Fate
Environmental Fate and Transpor t Properties of Homopolymer

This environmental fate assessment addresses the persistence and mobility of the parent compound homopolymer. Based on the chemical, physical, and environmental fate properties, homopolymer is miscible in water, non-volatil e, and stable to hydrol ysis and photodegradation, see Table 4. As a flocculant, homopolymer sorb s to organic material, soils and sediment. Additional environmental fate data for homopolymer are not anticipated to be required because, based on the label language, the agency assumes that backflow into surface water will not occur.

Appendix B References

Breithaupt, James. May 5, 2015. Review of M odified Activated Sludge Respiration Inhibition Study (OCSPP 850.3300) for Homopolymer. MRID 49437513, D427116

Ciba (year unknown). Flocculati on Theory and Application. http://www.siltstop.com/pdf/flo cculation-theory_application.pdf

Lyman, W.J., W.F. Reehl, and D.H. Rose nblatt. 1990. Handbook of Chemical Property Estimation Methods. American Chemical Society. ISBN O-8412-1761-0

Mostaghimi, Siroos. November 12, 1998. Hydrol ysis Waiver Request for CAT-FLOC CL.
D236082.

MRID 49437513. Licata-Messama, L. March 21, 1995. Test to Evaluate the Inhibition of Respiration in Activated Sludge (Test Substance: FL 45 CLV). Unpublished study performed by Societe d’Ecotoicologie et de Physico-Chimied, Sarcey, France, and submitted by the SNF, Inc. Study No. S.E.P.C. Report No. F065.Docket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 21 of 22



# Appendix C Ecotoxicology Profile

Toxicity to Aquatic Receptors

Freshwater Fish

Table 7 – Freshwater Fish and Amphibian Toxicity Data

Species Test Material (% a.i.) Toxicity Endpoint B Value Toxicity Category MRID/ Study Classification/ Comments

Rainbow trout ( Oncorhynchus mykiss ) VeliGon L-M (19.8%) 96-h LC 50 =0.077 ppm ai 95% CI = 0.59-0.11 ppm ai Probit slope = NA NOAEC = Not determined Very highly toxic 44148402/ Acceptable

Fathead minnow ( Pimephales promelas) VeliGon L-M (19.8%) 96-h LC 50 = 0.26 ppm ai 95% CI=0.17-0.48 ppm ai Probit slope = NA NOAEC = Not determined Highly toxic 44148401/ Acceptable

Rainbow trout ( Oncorhynchus mykiss ) VeliGon CL-M (39.8%) 96-h LC 50 =0.066 ppm ai 95% CI=0.043-0.12 ppm ai Probit slope=NA NOEAC=0.043 ppm ai Very highly toxic 44148405/ Acceptable

Fathead minnow ( Pimephales promelas ) VeliGon CL-M (39.8%) 96-h LC 50 =0.22 ppm ai 95% CI=0.19-0.26 ppm ai Probit slope=5.4 NOAEC=0.11 ppm ai Highly toxic 44148404/ Acceptable

Freshwater Invertebrates

Table 8 – Freshwater Invertebrate Toxicity Data

Species Test Material (% a.i.) Toxicity Endpoint B Value Toxicity Category MRID/ Study Classification/ Comments

Waterflea ( Daphnia magna ) VeliGon L-M (19.8%) 48-h EC 50 =0.075 ppm ai 95% CI = 0.059 – 0.11 ppm ai Probit slope= NA NOAEC= not determined Very highly toxic 44148403/ Acceptable

Waterflea ( Daphnia magna ) VeliGon (39.8%) 48-h EC 50 = 2.1 ppm ai 95% CI = 1.8 – 2.6 ppm ai Probit slope=NA NOAEC = 0.50 ppm ai Moderately toxic 156044/ SupplementalDocket Number EPA-HQ-OPP-2015-0255 www.regulations.gov

Page 22 of 22 

## References:

Ward, T.J., J.P. Magazu and R.L. Boeri. 1996. Acute Toxicity of VeliGon L-M to the Fathead Minnow, Pimephales promelas . T.R. Wilbury Laboratories, In c., Marblehead, MA. Lab. Report ID: 965-CA. MRID#: 44148401, Unpublished.

Ward, T.J., J.P. Magazu and R.L. Boeri. 1996. Acute Toxicity of VeliGon L-M to the Rainbow Trout, Oncorhynchus mykiss . T.R. Wilbury Laboratories, Inc. , Marblehead, MA. Lab. Report ID: 964-CA. MRID#: 44148402, Unpublished.

Ward, T.R., J.P. Magazu and R.L. Boeri. 1996. Acute Toxicity of VeliGon L-M to the Daphnid, Daphnis magna . T.R. Wilbury Laboratories, Inc., Ma rblehead, MA. Lab. Report ID: 963-CA. MRID#: 44148403, Unpublished.

Ward, T.J., P. Kowalski and R.L. Boeri, 1996. Acute Toxicity of VeliGon CL-M to the Fathead Minnow, Pimephales promelas . T.R. Wilbury laboratories, Inc., Marblehead, MA. Lab. Report ID: 962-CA. MRID#: 44148404, Unpublished.

Ward, T.J., P.L. Kowalski and R.L. Boeri. 1996. Acute Toxicity of VeliGon CL-M to the Rainbow trout, Oncorhynchus mykiss . T.R. Wilbury Laboratories, Inc., Marblehead, Ma. Lab. Report ID: 961-CA. MRID #: 44148405, Unpublished.

Ward, T.J., P.L. Kowalshi and R.L. Boeri. 1996. Acute Toxicity of VeliGon CL-M to the Daphnid, Daphnia magna . TR. Wilbury Laboratories, Inc., Marblehead, MA. Lab. Report ID: 960-CA. MRID#: 44148406, Unpublished.