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Potassium Hypochlorite Registration Review Team 

Human Health 

Jonathan Leshin 

Timothy Dole 

Environmental Fate and Effects 

David Bays 

Srinivas Gowda 

Najm Shamim 

Risk Management 

Donna Kamarei 

Rose Kyprianou 

Wanda Henson 

Office of General Counsel 

Philip Ross 
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TERMS, ABBREVIATIONS AND SYMBOLS 

AD Antimicrobials Division 

A.I. or a.i. active ingredient 

aPAD acute population adjusted dose 

ASRI activated sludge respiration inhibition 

atm-m3

/mole atmospheric pressure-cubic meter per mole 

BCF bioconcentration factor 

°C degrees Celsius 

CaSO4 calcium sulfate 

CaSO3 calcium sulfite 

CAS Chemical Abstracts Service 

CCA chromated copper arsenate 

CFR Code of Federal Regulations 

CHO Chinese hamster ovary 

CMA Chemical Manufacturers Association 

CO2 carbon dioxide 

COC concentration-of-concern 

cPAD chronic population adjusted dose 

CS2 carbon disulfide 

DCI data call-in 

EC50 median (or 50 percent) effect concentration

EC05 5 percent effect concentration

ECOTOX ECOTOXicology 

EDI estimated daily intake 

EDSP Endocrine Disruptor Screening Program 

E-FAST Exposure and Fate Assessment Screening Tool 

EPI Suite Estimation Program Interface Suite 

EPA Environmental Protection Agency 

FDA Food and Drug Administration 

FFDCA Federal Food, Drug, and Cosmetic Act 

FGD flue-gas desulfurization 

FIFRA Federal Insecticide, Fungicide, and Rodenticide Act 

FQPA Food Quality Protection Act 

FWP Final Work Plan 

g/mol grams per mole 

GLN guideline number 

HPV high production volume 

IDS Incident Data System 

KDDC potassium dimethyldithiocarbamate 

Koc organic carbon normalized soil-water partition coefficient 

Kd soil-water partition coefficient 

Kow octanol-water partition coefficient 

LC50 median (or 50 percent) lethal concentration 

LD50 median (or 50 percent) lethal dose 

LOAEC lowest-observed-adverse-effect-concentration 

LOEC lowest-observed-effect-concentration 

LOAEL lowest-observed-adverse-effect-level 

Log Kow logarithm of the octanol-water partition coefficient

μg microgram 

ml/g milliliter per gram 
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mg/kg milligram per kilogram 

mg/kg/day milligram per kilogram per day 

mg/L milligram per liter 

mm Hg millimeter of mercury 

MOE margin of exposure 

MRID Master Record Identification Number 

MRL maximum residue limit 

N/A not applicable 

NaDDC sodium dimethyldithiocarbamate salt 

nm nanometers 

NOAEC no-observed-adverse-effect-concentration 

NOAEL no-observed-adverse-effect-level 

OCSPP Office of Chemical Safety and Pollution Prevention 

OECD Organization for Economic Co-operation and Development 

OPP Office of Pesticide Programs 

PAD population adjusted dose 

PAI pure active ingredient 

PDM Probabilistic Dilution Model 

% percent 

PC Code Pesticide Chemical Code 

PCF pounds per cubic foot 

pH power of hydrogen or power of the concentration of the hydrogen ion 

PHED Pesticide Handler’s Exposure Data 

PIS primary irritation score 

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 

QSAR quantitative structure-activity relationship 

RED Reregistration Eligibility Decision 

SAR structure activity relationship 

SF safety factor 

SSTS Section Seven Tracking System 

SO2 sulfur dioxide 

TEP typical end-use product 

TGAI technical grade active ingredient 

TMDL total maximum daily loads 

UF uncertainty factor 

UV/VIS ultraviolet/visible light absorption 

% w/w percent weight per weight. 

WP wettable powder 

WWTPs wastewater treatment plants 

 
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Table of Contents 

1 Introduction ............................................................................................................................. 7

1.1 Statutory and Regulatory Authority ................................................................................. 7

1.2 Case Overview .................................................................................................................. 9

1.3 Chemical Identification and Properties ............................................................................ 9

1.4 Use/Usage Description ................................................................................................... 10

1.4.1 Registrations ............................................................................................................ 10

1.4.2 Summary of Registered Uses .................................................................................. 10

1.5 Regulatory History ......................................................................................................... 12

1.5.1 Tolerance Information ............................................................................................. 12

1.6 Incidents .......................................................................................................................... 12

1.6.1 Human Health ......................................................................................................... 12

1.6.2 Ecological ................................................................................................................ 12

2 Anticipated Data Needs ......................................................................................................... 12

3 Human Health Risk Assessment ........................................................................................... 13

3.1 Existing Toxicological Endpoints .................................................................................. 13

3.2 Dietary Exposure ............................................................................................................ 13

3.3 Occupational and Residential Exposures ....................................................................... 13

3.4 Aggregate and Cumulative Exposure ............................................................................. 14

3.4.1 Aggregate Exposures ............................................................................................... 14

3.4.2 Cumulative Exposures ............................................................................................. 14

4 Environmental Risk Assessment ........................................................................................... 14

4.1 Environmental Fate Assessment ..................................................................................... 14

4.1.1 Leaching [Wood/Paint/Antifoulant Paint/Plastic/Textiles/e.g., treated article] ...... 15

4.1.2 Water and Sediment ................................................................................................ 15

4.1.3 Soil .......................................................................................................................... 15

4.1.4 Air ............................................................................................................................ 15

4.1.5 Other media ............................................................................................................. 15

4.1.6 Waste Water Treatment Plants (WWTP) ................................................................ 15

4.1.7 Water Quality .......................................................................................................... 15

4.2 Ecological Effects Assessment ....................................................................................... 16

4.2.1 Mode of Action ....................................................................................................... 16

4.2.2 Measures of Effect (Ecotoxicology Assessment Endpoints) .................................. 16

4.3 Exposure Analysis Plan .................................................................................................. 17

4.3.1 Aquatic and Terrestrial Wildlife Exposure Estimates ............................................. 17

4.4 Effects Analysis Plan ...................................................................................................... 17

5 Endocrine Disruptor Screening Program (EDSP) ................................................................. 17

6 Guidance for Commenters .................................................................................................... 18

6.1 Preliminary Work Plan ................................................................................................... 18

6.1.1 Trade Irritants .......................................................................................................... 18

6.1.2 Water Quality .......................................................................................................... 18

6.1.3 Environmental Justice ............................................................................................. 19

6.1.4 Structure Activity Relationships ............................................................................. 19

6.1.5 Additional Information ............................................................................................ 20

7 Next Steps ............................................................................................................................. 20

8 References ............................................................................................................................. 21
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Appendix A Toxicology Profile ............................................................................................... 22

Appendix B Environmental Fate and Transport of Potassium Hypochlorite .......................... 23

Appendix C Ecotoxicology Profile .......................................................................................... 26

Appendix D Product Chemistry ............................................................................................... 30

List of Tables 

Table 1 – Summary of Anticipated Risk Assessments and Data Needs: Potassium Hypochlorite .. 8

Table 2 – Anticipated Registration Review Schedule ....................................................................... 8

Table 3 – Chemical Identification of Potassium Hypochlorite ......................................................... 9

Table 4 – Physical- Chemical and Environmental Fate Properties for Potassium Hypochlorite ...... 9

Table 5 – Summary of Potassium Hypochlorite Registered Uses .................................................. 10

Table 6 – Acute Toxicity Studies for Potassium Hypochlorite ....................................................... 22

List of Figures 

None. 

 
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1 Introduction 

This document is the United States Environmental Protection Agency’s (USEPA, EPA or “the 

agency”) Preliminary Work Plan (PWP) for potassium hypochlorite (case 5076). The PWP 

document explains what EPA's Office of Pesticide Programs (OPP) knows about potassium 

hypochlorite, highlighting anticipated data and assessment needs, identifying the types of 

information that would be especially useful to the agency in conducting the review, and providing 

an anticipated timeline for completing potassium hypochlorite’s review. 

The registration review process was designed to include a public participation component to solicit 

input from interested stakeholders. The agency intends, by sharing this information in the docket, 

to inform the public of what it knows about potassium hypochlorite and what types of new data or 

other information would be helpful for the agency to receive as it moves toward a decision on 

potassium hypochlorite. As explained further in this document, in the future, if appropriate the 

agency will evaluate this chemical with sodium and calcium hypochlorite (case 0029). The 

agency encourages all interested stakeholders to review the PWP and to provide comments and 

additional information that will help the agency’s decision-making process for this chemical. 

1.1 Statutory and Regulatory Authority 

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 USEPA 

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 regulations governing registration 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 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 (FWP) and anticipated schedule for the 

potassium hypochlorite case. Further, the agency believes that potassium hypochlorite is similar 

to and can be considered with the chemicals in case 0029, sodium and calcium hypochlorite. The 

docket for the sodium and calcium hypochlorite case opened in March 2012. No risk assessments 

are considered necessary for any of the three compounds since EPA has concluded that the 

currently registered uses of the hypochlorites will not result in unreasonable adverse effects to the 
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environment. Since no risk assessments are necessary, after the final workplan for potassium 

hypochlorite is issued, the agency intends to issue a combined proposed decision for all three 

compounds. 

Documents associated with this registration review can be viewed at http://www.regulations.gov

in docket EPA-HQ-OPP-2014-0157. Tables 1 and 2 below summarize the issues relevant to this 

registration review case and the anticipated registration review schedule. 

Table 1 – Summary of Anticipated Risk Assessments and Data Needs: Potassium 

Hypochlorite 

Risk Assessment 

Assessment 

Necessary to 

Support 

Registration 

Review 

Date of Most 

Recent 

Assessment 

Type of Assessment 

Required 

(New/Updated) 

Data Anticipated as Needed 

Dietary (food) No None None None 

Dietary (drinking water) No None None None 

Occupational Handler No None None None 

Residential Handler No None None None 

Residental Post 

Application No None None None 

Aggregate No None None None 

Cumulative No None None None 

Tolerance Review No None None None 

Ecological No None None None 

Table 2 – Anticipated Registration Review Schedule 

Anticipated Activity Target Date* Completion Date

Phase 1: Opening the Docket 

Open Docket and 60-Day Comment Period for Preliminary Work Plan 2014-03 March 26, 2014 

Close Public Comment Period 2014-05 

Phase 2: Case Development 

Issue Final Work Plan 2014-09 

Issue Data Call-In (DCI) N/A 

Receive Data to be Considered in Risk Assessment N/A 

Open 30-Day Public Comment Period for Preliminary Risk Assessment(s) N/A 

Close Public Comment Period N/A 

Phase 3: Registration Review Decision and Implementation 

Open 60-Day Public Comment Period for Proposed Decision 2016-09 

Close Public Comment Period 2016-11 

Issue Final Decision 2017-03 

Begin Post-Decision Followup 2017 

Total (years) 3 

*The anticipated schedule will be revised as necessary (e.g., need arising under the Endocrine Disruptor Screening Program with 

respect to the active ingredients in this case). 

N/A = Not applicable 
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1.2 Case Overview 

The docket for the potassium hypochlorite case (case 5076) has been established at 

http://www.regulations.gov in docket number EPA-HQ-OPP-2014-0157. 

1.3 Chemical Identification and Properties 

Table 3 presents the active ingredient to be assessed in case 5076: potassium hypochlorite (PC 

Code 129053). 

Table 3 – Chemical Identification of Potassium Hypochlorite 

Chemical Name Potassium hypochlorite 

Chemical Classification Halogen 

PC Code 129053 

CAS Number 7778-66-7 

Molecular Formula KOCl 

Molecular Weight (grams/mole) 90.55 

Purity 12.5% 

Available chlorine Contains approximately 1.0 lb of Available Chlorine/Gallon 

Molecular Structure 

The potassium hypochlorite product chemistry information relevant to risk assessment is 

summarized in Table 4 (source: MRIDs KOCl: 47382901, 47445101, and 47594501). 

Table 4 – Physical- Chemical and Environmental Fate Properties for Potassium 

Hypochlorite 

Guideline No. Parameter Potassium hypochlorite (12.5%) 

Physical/Chemical Properties 

830.7000 pH 10.14 - 1% w/w solution in de-ionized water at 21.1-

21.8°C 

830.7050 UV/Visible Absorption Does not absorb in uv visible range 

830.7200 Melting point Not required 

830.7220 Boiling point (oC) Decomposes prior to boiling 

830.7300 Density 1.1701 g/ml (9.75 lbs/gal) at 20.1°C 

830.7370 Dissociation constant (pKa) Potassium hypochlorite dissociates completely on 

dissolving in water. 

830.7550 Octanol-water partition coefficient at 25 °

C 

(Log Kow) NA 

830.7840 Solubility in water (mg/L) Complete 

830.7950 Vapor pressure (mmHg) NA 

atm-m3/mol = atmosphere cubic meter per mole; oC = degrees Celsius; mg/L = milligrams per liter; mmHg = 

millimeters of mercury. 
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1.4 Use/Usage Description 

1.4.1 Registrations 

There is one product (EPA Reg. Number 63838-10) that contains potassium hypochlorite. The 

product is a soluble concentrate and it contains 12.5 percent potassium hypochlorite which is 

equivalent to approximately 1.0 lb of available chlorine per gallon. The product was registered on 

March 3, 2011. 

1.4.2 Summary of Registered Uses 

Table 5 presents a summary of the registered uses of potassium hypochlorite that will be assessed 

in this registration review. 

Table 5 – Summary of Potassium Hypochlorite Registered Uses 

Use Treatment Type Application Method Product 

Application Rate 

Available 

Chlorine 

(ppm) 

Agricultural Premises and Equipment

Farm Premises Sanitization Surface and Immersion 14 oz/10 ga 1000 ppm 

Irrigation Systems 

Irrigation Systems Bacteria and 

Algae Growth 

Sprinkler, Flood, Furrow, 

Border or Drip Irrigation 5 ppm 

Food Handling/Storage Establishments, Premises and Equipment

Food Egg Sanitization Sanitization Spray 2.5 oz/10 ga 200 ppm 

Fresh Fruits and Vegetables 

(with potable water rinse) Sanitization Submersion or Drench 31 oz/250 ga 100 ppm 

Fruit and Vegetable Washing 

(without potable water rinse) Sanitization Spray 6.2 oz/200 ga 25 ppm 

Meat and Poultry Plants 

Processing Water Sanitization Circulate 1.4 oz/200 ga 5 ppm 

Non-Porous Food Contact 

Surfaces Sanitization 

Rinse, Immerse, Circulate 2.5 oz/10 ga 200 ppm 

Spray/Fog 7.5 oz/10 ga 600 ppm 

Porous Food Contact Surfaces Sanitization 

Rinse, Immerse, Circulate 7.5 oz/10 ga 600 ppm 

Spray/Fog 7.5 oz/10 ga 600 ppm 

Potatoes Sanitization Spray 0.5 oz/2 ga 500 ppm 

Poultry chiller water and 

carcass wash water Sanitization Circulate 14.4 oz/200 ga 50 ppm 

Commercial, Institutional and Industrial Premises and Equipment 
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Use Treatment Type Application Method Product 

Application Rate 

Available 

Chlorine 

(ppm) 

Non-Porous Non-Food 

Contact Surfaces 

Sanitization Rinse, Immerse, Circulate 2.5 oz/10 ga 200 ppm 

Spray/Fog 2.5 oz/10 ga 200 ppm 

Non-Porous Non-Food 

Contact Surfaces Disinfection Rinse, Immerse 7.5 oz/10 ga 600 ppm 

Porous Non-Food Contact 

Surfaces Sanitization Rinse, Immerse 7.5 oz/10 ga 600 ppm 

Laundry (Commercial) Sanitization Soak, Wash 2.5 oz/10 ga 200 ppm 

Residential and Public Access Premises 

Laundry (Household) Sanitization Soak, Wash 2.5 oz/10 ga 200 ppm 

Human Drinking Water Systems 

Drinking Water Disinfection Injection As needed* 0.6 ppm in system

Public Water Systems 

Mains 

New Tanks, Basins 

Sand Filters 

Well Casing 

Equipment 

Equipment 

Tank Cars 

Disinfection 

Injection 

Open Pour 

Open Pour 

Open Pour 

Open Pour 

Spray 

Spray 

As needed*

25 oz/5 ft3

100 oz/150 ft3

6.2 oz/10 ga 

26 oz/5 ft3 

6.2 oz/5 ga 

6.2 oz/10 ga 

50 ppm 

500 ppm 

Unspecified 

500 ppm 

500 ppm 

1000 ppm 

500 ppm 

Industrial Processes and Water Systems 

Cooling Towers Slug 

Maintenance Open Pour 130 oz/10,000 ga 14 oz/10,000 ga 

10 ppm 

1 ppm 

Pulp and Paper Process Water Slug 

Maintenance Open Pour 130 oz/10,000 ga 14 oz/10,000 ga 

10 ppm 

1.0 ppm 

Sewage and Wastewater Effluent 

Filter Beds Open Pour As needed 100 oz/20 ft2

0.5 ppm 

Unspecified 

Swimming Pools and Spas 

Swimming Pool Shock 

Maintenance Open Pour 130 oz/10,000 ga 14 oz/10,000 ga 

10 

1.0 

Spas and Hot Tubs Shock 

Maintenance Open Pour 10 oz/500 ga 6.5 oz/1000 ga 

19 

5.0 

Aquatic Areas 

Fish Hatchery Pond Open Pour 2.5 oz/10 ga 200 ppm 

Fish Pond Equipment Open Pour 2.5 oz/10 ga 200 ppm 

Fish Ponds Open Pour 130 oz/10,000 ga 10 ppm 

Maine Lobster Ponds Open Pour 7,700 oz/10,000 ga 600 ppm 

*The application rate is specified in terms of the chlorine residual and the amount of product applied will vary 

depending on the chlorine demand of the system being treated. 
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1.5 Regulatory History 

The first product containing potassium hypochlorite as an active ingredient was registered in 1998; 

by 2005 all the registered products were canceled. As of 2011 there was a new registration, with a 

variety of uses as outlined in Table 5. 

A Reregistration Eligibility Decision (RED) was not completed for potassium hypochlorite 

because it was registered after November 1, 1984. 

1.5.1 Tolerance Information 

An exemption from the requirement of a tolerance is established for residues of potassium 

hypochlorite in or on all commodities [40 CFR § 180.1300].1

1.6 Incidents 

1.6.1 Human Health 

As of January 30, 2013, no human health incidents are listed for potassium hypochlorite in the 

OPP’s Incident Data System (IDS). 

1.6.2 Ecological 

As of February 5, 2013, no ecological incidents are listed for potassium hypochlorite in OPP’s 

Incident Data System (IDS). 

2 Anticipated Data Needs 

The agency does not anticipate needing to call in any data to support this registration review.

 

1 http://www.ecfr.gov/cgibin/retrieveECFR?gp=1&SID=2035ef80559449db2dfc1f34c286e7ca&ty=HTML&h=L&r=SECTION&n=40y25.0.1.

1.27.4.19.197
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3 Human Health Risk Assessment 

Based on the toxicity profile and exposure scenarios for potassium hypochlorite, EPA believes 

that risks from chronic and subchronic exposures to this pesticide would be minimal and without 

consequences to human health. The agency believes that any acute corrosive risks will be 

sufficiently mitigated by precautionary labeling requiring protection of eyes and skin while using 

this pesticide. 

3.1 Existing Toxicological Endpoints 

During the generation of the 2014 registration review preliminary work plan, the agency 

conducted an in-depth review of the similarities between potassium hypochlorite and the existing 

registered active ingredients sodium hypochlorite and calcium hypochlorite. Based upon this 

review, the agency has determined that the data available to support the registrations of these 

active ingredients are also applicable to potassium hypochlorite. See Appendix A for toxicology 

profile. 

No additional generic or product-specific acute, chronic or subchronic toxicological studies are 

required for this registration review. All toxicology data will be bridged from studies on sodium 

and calcium hypochlorites based on their chemical similarity.2

 

Potassium hypochlorite is extremely corrosive and can cause severe damage to eyes and skin, 

and therefore has been classified Toxicity Category I based on these acute effects. The agency 

has determined that these risks are adequately mitigated through the use of the specific 

precautionary and first aid statements that have been proposed on the product labeling. Based on 

its similarity to sodium and calcium hypochlorite, potassium hypochlorite was assigned acute 

oral and dermal toxicities to category IV and acute inhalational toxicity to category III. This 

chemical is not a dermal sensitizer.2 

3.2 Dietary Exposure 

There are no toxicological endpoints for potassium hypochlorite; therefore, dietary food and 

drinking water exposures do not need to be assessed for registration review.

3.3 Occupational and Residential Exposures 

There are no toxicological endpoints for potassium hypochlorite; therefore, occupational and 

residential exposures do not need to be assessed for registration review. 

 

2 U.S. EPA 2012. Registration Review Final Work Plan: Na & Ca Hypochlorite. Docket Number EPA –HQ-OPP 

2012-0004.Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0004-0006. 
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3.4 Aggregate and Cumulative Exposure 

3.4.1 Aggregate Exposures 

There are no toxicological endpoints for potassium hypochlorite; therefore aggregate exposures 

do not need to be assessed for registration review. 

3.4.2 Cumulative Exposures 

There are no toxicological endpoints for potassium hypochlorite; therefore, cumulative 

exposures do not need to be assessed for registration review. 

4 Environmental Risk Assessment 

The agency has not previously conducted a risk assessment that supports a complete endangered 

species determination for potassium hypochlorite. A risk assessment was conducted on sodium 

and calcium hypochlorite salts for the RED in 1991. Since these chemicals are very similar in 

their mode of action, all are hypochlorites and release chlorine as the active ingredient, the 

information from the previous assessment of sodium and calcium hypochlorites will be used for 

potassium hypochlorite. If determined necessary during the registration review process, the 

agency will determine potential acute and chronic risks to aquatic organisms exposed to 

potassium hypochlorite that are transported from treatment sites into the aquatic environment. 

Such sites include pulp and paper mill process water systems. 

The registration review process will allow the agency to determine whether each use of the 

potassium hypochlorite 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. 

4.1 Environmental Fate Assessment 

As with the sodium and calcium hypochlorite case, the agency does not anticipate the need for an 

environmental fate assessment for potassium hypochlorite. Potassium hypochlorite uses are 

exclusively in aqueous medium, and potassium hypochlorite belongs to the hypochlorite class of 

compounds including lithium, sodium, and calcium hypochlorites. These hypochlorites 

dissociate in water to form hypochlorous acid (HOCl), which acts as the active in disinfecting 

and sanitizing scenarios. OCSPP’s test guideline series 835 are not applicable to inorganic 

substances, and thus the traditional fate studies like hydrolysis, photolysis, etc. are not 

appropriate for inorganic molecules like potassium hypochlorite.3

Hypochlorite (HOCl) oxidizes to chlorite (ClO2

-

), chlorate (ClO3

-

), and perchlorate (ClO4

-

) or 

reduces to chloride (Cl-

); and such speciation processes are summarized in Appendix B. 

 

3

 F.A. Cotton & G. Wilkinson (Advanced Inorganic Chemistry, 7th edition; chapter 4 and 5). 
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The agency has not conducted any environmental and transport exposure assessment for 

potassium hypochlorite. Potassium chemistry is similar to the same group cations like sodium 

and calcium. All salts of these metals are highly water soluble. The agency does not intend to 

conduct a down the drain assessment for potassium hypochlorite as further explained in section 

4.1.6. 

4.1.1 Leaching [Wood/Paint/Antifoulant Paint/Plastic/Textiles/e.g., treated 

article] 

Potassium hypochlorite is not registered for uses in wood treatment or as an antifoulant for boat 

and ship bottoms, or in paints. It is not embedded into plastics or used in surface treatment of 

textiles. 

4.1.2 Water and Sediment 

Potassium ions exist in earth’s crust, sediments, soils, clay and the binding is strong. 

Hypochlorite in water and soils speciate into oxidized species (chlorite, chlorate, perchlorate) or 

reduce to chloride, depending on the pHs of the medium.4

4.1.3 Soil 

The chemical behavior of potassium and hypochlorite in soil is the same in other media like 

water, sediment and clays.4 

4.1.4 Air 

Potassium ions can vaporize along with other species, but deposit back to the soils and dissolve 

in water.4 

4.1.5 Other media 

It is a key element for plants. It is present in the intercellular fluids in mammalian systems. Its 

recommended daily intake is: 3500 mg.4 

4.1.6 Waste Water Treatment Plants (WWTP) 

A down-the-drain assessment is not required for potassium hypochlorite, which forms 

hypochlorous acid instantly. Hypochlorous acid degrades and is unlikely to reach WWTP. 

Potassium ions are not of concern for WWTP.4 

4.1.7 Water Quality 

Potassium hypochlorite is 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 the 

agency’s National Pesticides Cause of Impairment of Waters website (searched February 6, 

2014).5

 In addition, no Total Maximum Daily Loads (TMDL) have been developed for

potassium hypochlorite, based on information provided at the agency’s National Pesticide 

 

4

 F.A. Cotton & G. Wilkinson (Advanced Inorganic Chemistry, 7th edition; chapter 4 and 5). 5

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885
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TMDL web site (searched February 6, 2014)6

. Potassium ions 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 the agency’s National Pesticides Cause of Impairment of 

Waters website (February 6, 2014)7. There are 175 TMDL/ impaired water bodies (OW’s list 

303(d)) listed for total residual chlorine (TRC) on a national level recorded between 2000-2007. 

TRC is defined as the “amount of remaining chlorine remaining after contact time and is equal to 

available residual chlorine + free available chlorine.” More information on impaired water 

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

4.2 Ecological Effects Assessment 

4.2.1 Mode of Action 

In the aquatic environment, toxic action is largely due to hypochlorous acid formed when 

potassium hypochlorite reacts with water. Adverse effects of hypochlorous acid are due mainly 

to its corrosive action. Acute necrosis may occur. Fish gills-structure may be damaged; gill 

necrosis can lead to respiratory problems and asphyxiation. The protective slime coating on fish 

also may be removed due to corrosive action. 

4.2.2 Measures of Effect (Ecotoxicology Assessment Endpoints)

4.2.2.1 Submitted Data 

Ecological effects data are used as measures of direct and indirect effects to aquatic and 

terrestrial organisms. Acute and chronic toxicity data from registrant-submitted studies 

conducted in accordance with the 850 OCSSP Harmonized Test Guidelines will be used to 

evaluate the potential direct and indirect effects of potassium hypochlorite to animals and plants. 

Additionally, as described below, relevant data from the EPA’s Office of Water and from the 

open literature also may be used to evaluate potential direct and indirect effects. 

All available ecotoxicity endpoints from studies submitted by registrants are tabulated and 

referenced in the Ecological Effects Profile (Appendix C). OPP uses the most sensitive of these 

endpoints for assessing acute and chronic risks to each aquatic receptor group. The potassium 

ion is an essential, naturally occurring element which is assumed to be non-toxic at the levels 

released by potassium hypochlorite use. 

4.2.2.2 Office of Water Data 

EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine8 provides additional data 

that will be used in this registration review case. The document contains a review of open 

literature on acute and chronic effects of chlorine. Based on the available toxicological 

endpoints, freshwater and saltwater organism acute and chronic water quality criteria (expressed 

 

6

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant_

group_name=PESTICIDES

7

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

8

 See EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine -1984(EPA, 1985) at: 

http://water.epa.gov/scitech/swguidance/standards/upload/2001_10_12_criteria_ambientwqc_chlorine1984.pdf
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as total residual chlorine (TRC) for freshwater and chlorine-produced oxidants (CPO) for 

seawater) are derived. The current values are as follows: 

 Freshwater Criterion Maximum Concentration = 19 μg/L; 

 Freshwater Criterion Continuous Concentration = 11 μg/L; 

 Saltwater Criterion Maximum Concentration = 13 μg/L; and 

 Saltwater Criterion Continuous Concentration = 7.5 μg/L. 

4.2.2.3 Open Literature 

Since the agency does not anticipating conducting an environmental risk assessment, no effects 

analysis plan is needed; therefore no ECOTOxicology (ECOTOX) will be conducted. 

4.3 Exposure Analysis Plan 

4.3.1 Aquatic and Terrestrial Wildlife Exposure Estimates 

Available OPP models will be used to determine the estimated environmental concentration 

(EECs) in the aquatic environment. Resulting exposure estimates will be compared to the 

toxicity endpoints to determine if levels of concern are exceeded for each receptor group. 

4.4 Effects Analysis Plan 

Since the agency does not anticipating conducting an environmental risk assessment, no effects 

analysis plan is needed. 

5 Endocrine Disruptor Screening Program (EDSP) 

As required by FIFRA and 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 its most recent registration decision for potassium hypochlorite, 

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), 

potassium hypochlorite 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 
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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. A second list of chemicals 

identified for EDSP screening was published on June 14, 20139

 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 likely endocrine disruptors. 

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

chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our 

website.10

6 Guidance for Commenters 

6.1 Preliminary Work Plan 

The public is invited to comment on EPA’s Preliminary Work Plan and rationale. The agency 

will carefully 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 potassium hypochlorite registration 

review case. 

6.1.1 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. The agency 

will work to harmonize tolerances and international maximum residue limits (MRLs) and may 

modify tolerance levels to do so, when possible. Stakeholders are asked to comment on any trade 

irritant issues resulting from lack of 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. 

6.1.2 Water Quality 

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 

 

9

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

chemicals. 10 http://www.epa.gov/endo/ 
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Registration Review Risk Assessment and Management Process11 in order to ensure they can be 

used quantitatively or qualitatively in pesticide risk assessments. 

6.1.3 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 potassium hypochlorite 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. 

6.1.4 Structure Activity Relationships 

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

the agency. In the 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-theevidence evaluation. 

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 

 

11 http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm
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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 the 

potassium hypochlorite case, 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. Presubmission consultation with the agency is encouraged. 

6.1.5 Additional Information 

Stakeholders are also specifically asked to provide available information and data that will assist 

the agency in refining its risk assessments, including any species-specific ecological effects 

determinations. The agency is interested in receiving the following information: 

1. State or local use restrictions 

2. Ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and 

mammalian mortalities) not already reported to the agency 

3. Monitoring data 

7 Next Steps 

After the 60-day comment period closes in May 2014, the agency will review and respond to any 

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

hypochlorite case. 
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8 References 

U.S. Environmental Protection Agency (EPA). 2012. 

Registration Review Final Work Plan: Na & Ca Hypochlorite. 

Docket Number EPA –HQ-OPP-2012-0004. 

Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-

0004-0006. 
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Appendix A Toxicology Profile 

Acute Toxicity for Product Labeling 

No toxicological studies are required to be submitted. All toxicology data are waived based on 

the chemical’s similarity with sodium and calcium hypochlorites. Agency reviews regarding 

potassium hypochlorite have suggested that the registration review of this chemical may be 

treated similarly for the proposed uses. The decision not to require acute toxicity testing is 

supported by the proposed chemicals’ similarities with sodium, calcium and lithium hypochlorite 

and the chlorinated isocyanurates, whose RED documents considered their acute hazard data 

bases to be complete.12

Table 6 – Acute Toxicity Studies for Potassium Hypochlorite 

Guideline No./ Study 

Type MRID No. Results Toxicity Category

870.1100/ 

Acute oral toxicity 

Waived N/A IV

870.1200/ 

Acute dermal toxicity 

Waived N/A IV

870.1300/ 

Acute inhalation toxicity 

Waived N/A III 

870.2400/ 

Acute eye irritation 

Waived N/A I 

870.2500/ 

Acute dermal irritation 

Waived N/A I 

870.2600/ 

Skin sensitization 

Waived N/A Non-sensitizer

N/A=Not available 

All studies, subchronic and chronic, are not anticipated to be required for this chemical due to its 

similarities with sodium, calcium and lithium hypochlorite.

 

12 http://www.epa.gov/opp00001/chem_search/reg_actions/reregistration/red_G-77_1-Feb-92.pdf
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Appendix B Environmental Fate and 

Transport of Potassium Hypochlorite 

Note: Inorganic substances like potassium hypochlorite do not undergo degradation or 

transformation processes. Following chemical aspects are provided to understand the fate of 

inorganic substances like potassium hypochlorite. 

Using available chlorine formula (AC): molar mass of chlorine/ molar mass of the hypochlorite 

in use, we find the following: 

%AC = 71 g/mol of chlorine/ 90.5g/mol of potassium hypochlorite = 78.5%, 

While for NaOCl, the AC = 95.5%, thus both hypochlorites are chemically similar but the 

available chlorine from sodium hypochlorite makes it a stronger disinfectant. 

KOCl + H2O  HOCl + KOH; it is the HOCl is which is the active moiety for all 

hypochlorites in aqueous medium. The dissociation constant (Kdiss) of HOCl is: 3.4 x10-8 or pKa 

= 7.7. Hence at any given time, the concentration of HOCl is not very high, and as it gets used up 

more HOCl is formed and so on. It also means that at pH 7.7, the ratio of HClO/ClO-

 is 50/50, 

while at pH 7.2, 70% it is HClO and 30% ClOThe numerical data on the percent of HClO and ClO-

 from pH 4 to 11 as shown below: 

pH 4 100% HClO 

pH 6.3 95% HClO/5% ClOpH 7.2 70% HClO / 30% ClOpH 7.7 50% HClO/50% ClOpH 8.0 21% HClO/79% ClOpH 11 100% ClO- 

 *Chlorine is one the most versatile elements, particularly in regards to its reaction with oxygen. 

Chlorine shows numerous oxidation states (states of reactivity, from + 7 to -1). The following 

diagrams illustrate a number of facts: a) from the highest oxidation state in ClO4

-

 of + 7 to -1 in 

Cl-

 the reduction potentials are such that the reactions take place spontaneously in acidic or basic 

aquatic medium; b) The reverse reactions such as from Cl- to the formation of ClO4

-

 are not 

spontaneous.13

 

13 U.S. EPA 2012. Registration Review Final Work Plan: Na & Ca Hypochlorite. Docket Number EPA –HQ-OPP2012-0004.Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0004-0006. 
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Under acidic conditions: 

ClO4

-  ClO3-

  ClO2

-

 HClO2 HOCl Cl2 Cl- 

1 2 3 4 5 6 7 

Where: 

1 = perchlorate ion 

2= chlorate ion 

3= chlorite ion 

4= chlorous acid 

5= Hypochlorous acid 

6= chlorine 

7= chloride ion 

Note: the oxidation state of chlorine in 1 = +7 and Oxidation state in 7 = -1 

Under basic conditions: 

ClO4

-

  ClO3

-  ClO2  ClO2-  OCl-  Cl2  Cl-

 

1 2 3’ 3 5’ 6 7 

Where 3’= chlorine dioxide and 5’ = hypochlorous ion 

* Under direct sunlight, hypochlorite decomposes into hydrogen chloride and oxygen. Under 

prolonged sunlight exposure there is a likelihood of the formation of chlorate ion (ClO3

-

) in small 

quantities. 

* In the surface water and wastewater streams possible transformation products like chlorine, 

HOCl, ClO3

-

 may be present, but the determination of exact amounts of these moieties cannot be 

made as these concentrations will depend of the environmental conditions like pH of the 

medium, temperature, ionic strength, etc.14,15

Environmental Fate and Transport of Potassium Hypochlorite 

Water and Sediment 

Hydrolysis 

Not applicable for inorganic substances. Guidelines 835 are designed for organic substances. 

 

14 U.S. EPA 2012. Registration Review Final Work Plan: Na & Ca Hypochlorite. Docket Number EPA –HQ-OPP2012-0004.Available at: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0004-0006. 15 F.A. Cotton & G. Wilkinson (Advanced Inorganic Chemistry, 7th edition; chapter 4 and 5). 
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Aqueous Photolysis 

Not applicable for inorganic substances. Guidelines 835 are designed for organic substances. 

Octanol-Water Partition Coefficient 

Not applicable for inorganic and ionic substances. Guidelines 835 are designed for organic 

substances. 

 
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Appendix C Ecotoxicology Profile 

For the ecotoxicity assessment of potassium hypochlorite, studies testing sodium and calcium 

hypochlorite were used. No studies are available testing the potassium ion. This is acceptable, 

since all hypochlorites have a similar mode of toxicity. They are chlorine releasers, which can 

cause toxicity to non-target organisms. 

Toxicity to Terrestrial Organisms 

Birds 

An acceptable acute-oral (LD50) study categorizes sodium and calcium hypochlorite as being 

practically nontoxic to birds. The guideline for an acute-oral test (850.2100) is satisfied. Dietary 

studies (850.2200) are not anticipated to be required. However, four dietary studies have been 

submitted and indicate that hypochlorites are practically nontoxic to birds when administered in 

the diet. No additional data avian toxicity data are needed. 

Avian Acute-oral and Dietary Toxicity

Test Species Toxicity Toxicity 

Category

EPA Study 

ID

Mallard 

(Anas platyrhynchos) LC50 >5000 ppm Practically nontoxic 00007404 

Acceptable 

Northern bobwhite 

(Colinus virginianus) 

LD50 =3474 ppm for Ca 

hypochlorite 

LD50 = 2510 for Na 

hypochlorite 

Practically nontoxic 00007403Acceptable 

LC50 >,5000 ppm Practically nontoxic 00007405

Acceptable 

Nontarget Insects 

Toxicity data for beneficial insects (850.3020, 850.3030) are not required for the use patterns of 

potassium hypochlorite. 

Toxicity to Aquatic Organisms 

Freshwater Fish 

The available acute toxicity studies categorize sodium and calcium hypochlorite as being highly 

toxic to freshwater fish. The guideline (850.1075) for acute toxicity testing is satisfied. No 

chronic data (fish early-life stage, 850.1400) are available. However, the need for chronic 

toxicity data can be fulfilled from EPA’s Office of Water’s Ambient Water Quality Criteria for 

Chlorine - 1984 (EPA 1985). No additional fish toxicity data are anticipated to be needed. 
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Acute Toxicity to Freshwater Fish

Freshwater Invertebrates 

The acute toxicity study for the waterflea categorizes sodium hypochlorite as being very highly 

toxic to freshwater invertebrates. The guideline (850.1010) for acute toxicity testing is satisfied. 

No chronic data (life-cycle, 850.1300) are available. However, the need for chronic toxicity data 

can be fulfilled from EPA’s Office of Water’s Ambient Water Quality Criteria for Chlorine - 

1984 (EPA 1985). No additional aquatic invertebrate toxicity data are anticipated to be needed. 

Toxicity to Freshwater Invertebrates

Test Species Toxicity Endpoint 

(μg ai/L) 

Toxicity 

Category 

EPA Study 

ID 

Waterflea 

(Daphnia magna) 48-hr EC50 = 0.037 to 2.3 

ppm Very highly toxic 

00007402 

00019313 

Acceptable 

Estuarine/Marine Fish and Invertebrates 

The agency anticipates using the available data from EPA’s Office of Water’s Ambient Water 

Quality Criteria for Chlorine - 1984 (EPA 1985). 

Test Species Toxicity Endpoint 

(μg ai/L) 

Toxicity 

Category 

EPA Study 

ID 

Rainbow Trout 

(Oncorhynchus 

mykiss) 96-hr LC50 =0.13 to 1.35 

ppm Highly toxic 00008191 

Acceptable

Bluegill 

(Lepomis 

macrochirus) 96-hr LC50 =0. 28 to 2.1 

ppm Highly toxic 00008190 

Acceptable 

Test Species Toxicity Endpoint 

(μg ai/L) 

Toxicity 

Category 

EPA Study 

ID 

 
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Aquatic Plants 

No data are available. Studies needed for the TGAI include a toxicity test with a vascular 

species (850.4400), toxicity tests (850.4500) with 3 algal species (green algae, freshwater 

diatom, marine diatom), and a toxicity test using cyanobacteria (850.4550); to address these 

needs, the agency anticipates using the available data from EPA’s Office of Water’s Ambient 

Water Quality Criteria for Chlorine - 1984 (EPA 1985). 

Sediment toxicity 

Based on the environmental-fate properties of potassium hypochlorite (see section 4.1), sediment 

toxicity data are not anticipated to be required. 

Appendix C References 

00007403 Beavers, J.B.; Fink, R.; Grimes, J.; et.al. (1978) Final Report: Acute Oral LD50- 

Bobwhite Quail: Project No. 158-103. (Unpublished study received Jan 19 under 

unknown admin. No.; prepared by Wildlife International, Ltd. In cooperation with 

Washington College, submitted by Chlorine Institute, Inc., New York, N.Y.; 

CDL236804-B) 

00007404 Beavers, J.B.; Fink, R.; Grimes, J.; et.al. (1978) Final Report: Eight-Day Dietary 

LC50-mallard Duck: Project No. 158-102. (Unpublished study received Jan 19, 

1979. Under unknown admin. No.; prepared by Wildlife International, Ltd. In 

cooperation with Washington, submitted by Chlorine Institute, Inc., New York, 

N.Y.; CDL:236804-C) 

00007405 Beavers, J.B.; Brown, R. (1978) Final Report: Eight-Day Dietary LC50-Bobwhite 

Test Species Toxicity Endpoint 

(μg ai/L)

Toxicity 

Category

EPA Study 

ID

Marine Fish 

(Cyprinodon 

variegates)

96-hr LC50 =0.38 mg/L 

NOAEC = 0.225 mg/ Highly toxic 47642401 Acceptable

Mysid Shrimp 

(Americamysis 

bahia) 

96-hr LC50 =0.16 mg/L 

NOAEC = 0.14 mg/ Highly toxic 

47642402 

Acceptable 

Eastern Oyster 

(Crassostrea 

virginica) 

96-hr EC50 =0.20 mg ai /L 

NOAEC = 0.13 mg ai/L Highly toxic 

47642403 

Acceptable 
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Quail: Project No. 158-101. (Unpublished study received Jan 19, 1979 under 

unknown admin. No.; prepared by Wildlife International, Ltd., submitted by 

Chlorine Institute, inc., New York, N.Y.; CDL:236804-D) 

00008190 Calmbacher, C.W. (1978) Acute Toxicity of Sodium hypochlorite Solution to the 

Bluegill Sunfish “Lepomis macrochirus” Rafinesque: UCES Proj. No. 11506-72-

01. (Unpublished study received Apr 4, 1978 under 35317-1; prepared by Union 

Carbide Corp., submitted by Kuehne Chemical Co., Inc., Cranford, N.J.; 

CDL:233389-A) 

00008191 Calmbacher, C.W. (1978) Acute Toxicity of Sodium hypochlorite Solution to the 

Rainbow Trout, “Salmo gairdneri” Richardson: UCES Project. No. 11506-72-02. 

(Unpublished study received Apr 4, 1978 under 35317-1; prepared by Union 

Carbide Corp., submitted by Kuehne Chemical Co., Inc. Cranford, N.J.; 

CDL:233390-A) 

00019313 LeBlanc, G.A. (1977) Acute Toxicity for Sodium hypochlorite Solution to the 

Water Flea (Daphnia magna): ICG/T-78-076. (Unpublished study received Dec 7, 

1978 under 230-69; prepared by EG&G, Bionomics, submitted by FMC Corp., 

Industrial Chemical Group, Philadelphia, Pa.; CDL:236584-B) 

47642401 MacGregor, R. (2008) Marine Fish (Cyprinodon variegates) Definitive 96-hour 

Acute Toxicity Test with Daily Dosing. Prepared by Baroid Bioassay Lab; 

submitted by Halliburton Energy Services, Inc, OK; Study No.: S4546 

47642402 MacGregor, R. (2008) Mysid Shrimp (Americamysis bahia) Definitive 96-hour 

Acute Toxicity Test with Daily Dosing; prepared by Baroid Bioasssay Lab; 

submitted Halliburton Energy Services, OK; Study No.: S4547 

47462403 Gallagher, S.P.; Kendall, T.Z.; Krueger, H.O. (2008) BE-7 antimicrobial (Sodium 

Hypochlorite 12.5% w/v): A 96-hour Shell Deposition Test with the Eastern 

Oyster (Crassostrea virginica); prepared by Wildlife International, Ltd; submitted 

by Halliburton Energy Services, Inc., OK; Study No.: 666A-101 

 
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Appendix D Product Chemistry 

Potassium hypochlorite product chemistry information is summarized in Table D1 (source: 

MRIDs 47382901, 47445101, and 47594501). 

Table D1 – Product Chemistry of Potassium hypochlorite 

Guideline 

No. Physical and Chemical Properties Potassium hypochlorite 

830.1550 Product identity and composition Refer to Table 3. 

830.1600 Description of materials used to produce 

the product 

Confidential Business Information (CBI). 

830.1620 Description of production process CBI. 

830.1650 Description of Formulation Process CBI. 

830.1670 Discussion of Formation of Impurities CBI. 

830.1700 Preliminary analysis CBI. 

830.1750 Certified limits CBI. 

830.1800 Enforcement analytical method 

The enforcement analytical method for potassium hypochlorite 

solutions is based on ASTM D 2002-89(2003) entitled 

“Standard Test Methods of Sampling and Chemical Analysis of

Chlorine-Containing Bleaches”. 

830.1900 Submittal of samples CBI. 

830.6302 Color Pale yellow. 

830.6303 Physical State Aqueous solution- pale yellow. 

Liquid at 20.1°C. 

830.6304 Odor Chlorine bleach smell. 

830.6313 Stability to normal and elevated 

temperature, metals/metal ions 

Stable under ordinary conditions of use and storage. 

Unstable at elevated temperatures. 

Reacts vigorously with amine, ammonium, salts, reducing 

agents, methanol, acids and most organics. 

Strong reducing agents such as nitrites, sulfides, sulfites, 

metabisulfites, and thiosulfates are incompatible, and their 

contact with potassium hypochlorite should be prevented. 

830.6314 Oxidation/Reduction Strong Oxidizing Agent. 

830.6315 Flammability Not applicable. Noncombustible. 

830.6316 Explodability Not explodable. 

830.6320 Corrosion Characteristic 

Corrosive. 

Potassium hypochlorite solution is corrosive to metals such as 

stainless steel, mild steel, iron, copper, zinc, and aluminum. 

Potassium hypochlorite solution should not contact these 

materials. 

830.7000 pH 10.14 - 1% w/w solution in de-ionized water at 21.1-21.8°C. 

830.7050 UV/Visible Absorption Not reported. 

830.7100 Viscosity 1.1 mm2/sec at 20.6°C and 0.9 mm2/sec at 40°C. 

830.7200 Melting point Not required. 

830.7220 Boiling point Decomposes prior to boiling. 

830.7300 Density 1.1701 g/ml (9.75 lbs/gal) at 20.1°C. 
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Guideline 

No. Physical and Chemical Properties Potassium hypochlorite 

830.7370 Dissociation Constant Potassium hypochlorite dissociates completely on dissolving 

in water. 

830.7550 Partition coefficient (n-octanol/water) Not applicable. 

830.7840 Solubility in water Complete. 

830.7860 Solubility in organic solvents NA Product should be mixed only with water. 

830.7950 Vapor pressure Approximately that of air. 

A Confidential business information 

atm-m3/mol = atmosphere cubic meter per mole; oC = degrees Celsius; mg/L = milligrams per liter; mmHg = 

millimeters of mercury.