United States Chemical Safety March 2011 

Environmental Protection and Pollution Prevention 

Agency (7510P) 

 

Tetrakis(Hydroxymethyl) 

Phosphonium Sulfate (THPS) 

Summary Document: 

Registration Review 

 

Docket Number: EPA-HQ-OPP-2011-0067 

www.regulations.gov

TABLE OF CONTENTS 

Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) Registration Review Team .........4 

I. Preliminary Work Plan .....................................................................................................5

II. Fact Sheet ......................................................................................................................12 

III. Summary of Anticipated Data Requirements ..............................................................17 

IV. Appendix A ..................................................................................................................19 

________________________________________ 

Please Note 

This Preliminary Work Plan and Fact Sheet summarize the Environmental Protection Agency's 

current position based on the following documents: 

1. Scoping Document: Product Chemistry/Environmental Fate/Ecotoxicity of Tetrakis 

(hydroxymethyl) Phosphonium Sulfate. 

2. Summary of Human Health Effects Data for the THPS Registration Review Decision 

Document. 

Additional supporting documents for the Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) 

Case may be found in the registration review docket EPA-HQ-OPP-2011-0067 located on the 

internet at www.regulations.gov. 

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Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) Registration Review Team

Human Health & Environmental Effects

Nathan Mottl 

Najm Shamim 

Risk Management

Eliza Blair 

Lance Wormell 

Office of General Counsel

Philip Ross 

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I. Preliminary Work Plan -- Tetrakis(Hydroxymethyl) Phosphonium Sulfate (THPS) 

Introduction:

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

pesticides distributed or sold in the United States generally must be registered by the U.S. 

Environmental Protection Agency (USEPA, EPA, or the Agency) based on scientific data 

showing that they will not cause unreasonable risks to human health or the environment when 

used as directed on product labeling. The registration review program is intended to make sure 

that, as the ability to assess risk evolves and as policies and practices change, all registered 

pesticides continue to meet the statutory standard of no unreasonable adverse effects to human 

health or the environment. Changes in science, public policy, and pesticide use practices will 

occur over time. Through the registration review program, the Agency periodically reevaluates 

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

Information on this program is provided at http://www.epa.gov/oppsrrd1/registration_review/. 

The Agency is implementing the registration review program pursuant to Section 3(g) of the 

Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and will review each registered 

pesticide every 15 years to determine whether it continues to meet the FIFRA standard for 

registration. The Agency will consider benefits information and data as required by FIFRA. The 

public phase of registration review begins when the initial docket is opened for each case. The 

docket is the Agency’s opportunity to state what it knows about the pesticide and what additional 

risk analyses and data or information it believes are needed to make a registration review 

decision. After reviewing and responding to comments and data received in the docket during 

this initial comment period, the Agency will develop and commit to a final work plan and 

schedule for the Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) Case. 

The first product containing Tetrakis(hydroxymethyl) phosphonium sulfate (THPS or THPS) 

(PC Code 129058) as an active ingredient was registered in the United States in 1995. Currently 

there are 15 products containing tetrakis(hydroxymethyl)phosphonium sulfate (THPS) registered 

with EPA. The products are registered for use as a materials preservative in paperboard 

manufacturing, coatings, pigments, emulsions and solutions, and fire protection systems. The 

products are also registered for antifoulant use in recirculating industrial process and water 

systems and oilfield recovery operations (drilling muds, packer fluids, pipeline pigging and 

scraping, and hydrotesting, among other applications). There are no pesticide tolerances or 

exemptions from the requirement of a tolerance for this chemical. 

A Reregistration Eligibility Decision (RED) was not issued for THPS, because it was first 

registered after November 1, 1984. 

Documents associated with the registration review of Tetrakis(hydroxymethyl)phosphonium 

sulfate (THPS) can be viewed at www.regulations.gov in docket EPA-HQ-OPP-2011-0067. 

Below is a summary of the issues relevant to the registration review case. 

The Agency believes that THPS may be a formaldehyde releaser because it contains a 

hydroxymethyl group, which is essential to the production of formaldehyde; additionally, the 

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degradation products observed in an aquatic medium are trihydroxymethyl phosphine (THP) 

molecules, which are formed by releasing two formaldehyde (HCHO) molecules. 

Anticipated Risk Assessment and Data Needs:

The Agency anticipates the need to conduct a comprehensive ecological risk assessment, 

including an endangered species risk assessment, for all uses of THPS. The Agency anticipates 

the need to conduct a human health risk assessment as well. The Agency anticipates needing 

additional data to conduct the registration review for THPS. 

Ecological Risk: 

• No recent ecological risk assessment has been performed for THPS. The most recent 

ecological risk assessment was performed in 1995 in support the initial registration of a 

product containing THPS. 

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

species determination for THPS. The ecological risk assessment planned during 

registration review will allow the Agency to determine whether THPS’s use has 'no 

effect' or 'may affect' federally listed threatened or endangered species (listed species) or 

their designated critical habitats. When an assessment concludes that a pesticide’s use 

'may affect' a listed species or its designated critical habitat, the Agency will consult with 

the U.S. Fish and Wildlife Service and/or National Marine Fisheries Services (the 

Services), as appropriate. 

• The Agency anticipates the need to require the following additional ecological data for 

the registration review of THPS. 

850.1010 -- Aquatic invertebrate acute toxicity, freshwater daphnids 

850.1300 -- Daphnid chronic toxicity test 

850.1350 -- Mysid chronic tox - aquatic invertebrate life-cycle (saltwater) 

850.4400 -- Aquatic plant toxicology test using Lemna spp., Tier I 

850.1400 -- Fish early-life stage toxicity test (freshwater) 

850.5400 -- Algal Toxicity Tier I and Tier II 

• The Agency anticipates the need to require the following additional environmental fate 

data for the registration review of THPS. 

835.2240 -- Photodegradation in water 

835.1230 -- Sediment and soil adsorption/desorption 

835.1240 -- Leaching and adsorption/desorption 

835.4300 -- Aerobic aquatic metabolism 

835.4400 -- Anaerobic aquatic metabolism 

835.3110 -- Ready Biodegradability 

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• For more information, please refer to Scoping Document: Product 

Chemistry/Environmental Fate/Ecotoxicity of Tetrakis (hydroxymethyl) Phosphonium 

Sulfate, located in the docket. 

Human Health Risk: 

• No recent human health risk assessment has been performed for THPS. The most recent 

human health risk assessment was performed in 1995 in support the initial registration of 

a product containing THPS. 

• The Agency anticipates the need to require the following additional human health data 

for the registration review of THPS. 

870.3465 -- 90-day inhalation toxicity (rat) 

875.1100 -- Dermal outdoor exposure 

875.1200 -- Dermal indoor exposure 

875.1300 -- Inhalation outdoor exposure (HRSB costs not included) 

875.1400 -- Inhalation indoor exposure 

875.1600 -- Application exposure data reporting and calculations 

875.1700 -- Product use information 

• Because the use of THPS in paints and coatings may result in inhalation exposure to 

users, the Agency will also need air monitoring data and would expect to require the 

following data to examine THPS and formaldehyde inhalation exposure. The studies 

anticipated as needed would be: 

875.2500 -- Inhalation exposure 

875.2700 -- Product use information 

875.2900 -- Data reporting and calculations 

• For more information, please refer to Summary of Human Health Effects Data for the 

THPS Registration Review Decision Document, located in the docket. 

Product Chemistry: 

• The Agency anticipates the need to require the following additional product chemistry 

data for the registration review of THPS. 

830.7840 -- Solubility in organic solvents in g/100 ml 

• For more information, please refer to Scoping Document: Product 

Chemistry/Environmental Fate/Ecotoxicity of Tetrakis (hydroxymethyl) Phosphonium 

Sulfate, located in the docket. 

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Endocrine Disruptor Screening Program

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, 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), THPS is subject to the 

endocrine screening part of the Endocrine Disruptor Screening Program (EDSP). 

EPA has developed the EDSP to determine whether certain substances (including pesticide 

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

produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator 

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

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 

interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

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

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. THPS is not 

among the group of 58 pesticide active ingredients on the initial list to be screened under the 

EDSP. Accordingly, as part of registration review, EPA will issue future EDSP orders/data callins, requiring the submission of EDSP screening assays for THPS. For further information on the 

status of the EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test 

guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/. 

Timeline

EPA has created the following estimated timeline for the completion of the 

Tetrakis(hydroxymethyl)phosphonium sulfate (THPS) registration review: 

 

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Anticipated Schedule

Activities Estimated Month/Year

Phase 1: Opening the docket 

Open Public Comment Period for Docket March 2011 

Close Public Comment Period for Docket May 2011 

Phase 2: Case Development 

Develop Final Work Plan (FWP) September 2011 

Issue DCI June 2012 

Data Submission June 2014 

Open Public Comment Period for Preliminary Risk Assessments December 2015 

Close Public Comment Period for Preliminary Risk Assessments February 2016 

Phase 3: Registration Review Decision 

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

Close Public Comment Period for Proposed Reg. Review Decision September 2016 

Final Decision and Begin Post-Decision Follow-up 2016 

Total (years) 5.5 

Guidance for Commenters:

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 Tetrakis(hydroxymethyl)phosphonium 

sulfate (THPS) registration review case. 

Trade Irritants:

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

irritants and, to the extent feasible, take steps toward facilitating irritant resolution. Growers and 

other stakeholders are asked to comment on any trade irritant issues resulting from lack of 

Maximum Residue Limits (MRLs) or disparities between U.S. tolerances and MRLs in key 

export markets, providing as much specificity as possible regarding the nature of the concern. 

Water Quality:

THPS 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 

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=88

5. In addition, no Total Maximum Daily Loads (TMDL) have been developed for THPS, based 

on information provided at 

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

=885&p_pollutant_group_name=PESTICIDES. 

More information on impaired water bodies and TMDLs can be found at 

http://www.epa.gov/owow/tmdl/. The Agency invites submission of water quality data for this 

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pesticide. To the extent possible, data should conform to the quality standards in Appendix A of 

the OPP Standard Operating Procedure: Inclusion of Impaired Water Body and Other Water 

Quality Data in OPP’s Registration Review Risk Assessment and Management Process (see: 

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

data can be used quantitatively or qualitatively in pesticide risk assessments. 

Environmental Justice:

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

people, regardless of race, color, national origin, or income, in the development, implementation, 

and enforcement of environmental laws, regulations, and policies. To help address potential 

environmental justice issues, the Agency seeks information on any groups or segments of the 

population who, as a result of their location, cultural practices, or other factors, may have 

atypical, unusually high exposure to THPS compared to the general population. Please comment 

if you are aware of any sub-populations that may have atypical, unusually high exposure 

compared to the general population. 

Structure Activity Relationships: 

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

the Agency. In the Office of Pesticide Programs (OPP), the evaluation process for a pesticide 

chemical traditionally begins with the applicant’s submission of a set of studies conducted with 

the specific pesticide chemical of interest. The use of the results of such testing (measured data) 

is a logical, scientifically rigorous process that identifies the physical, chemical, and 

environmental fate properties of the pesticide, as well as the dose and endpoints at which an 

adverse effect can occur in various animal species. 

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

generation that could significantly inform the Agency’s decision-making process. Recently, 

OPP has made increasing use of structure activity relationship (SAR) as part of its regulatory 

decision-making process. In the SAR process, a chemical's molecular structure is compared to 

that of other chemicals for which data are available. These structural similarities are then used to 

make predictive judgments about a chemical’s physical, chemical, and biological properties. 

Thus, the chemical’s physical, chemical, and biological properties are a function of (or directly 

related to) the chemical’s molecular structure. Quantitative SAR is referred to as QSAR. To 

develop a QSAR, a selected set of measured data on a single physical, chemical, or biological 

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

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

scientists, OPP has begun a process shift that envisions shifting from the current study-by-study 

approach to an approach in which the use of predicted data, generated using validated models, is 

considered along with information from open literature and studies specifically generated under 

Part 161 requirements. All relevant information would be considered as part of a weight-of-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 

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for many antimicrobial pesticide chemicals. When considering biological properties, at this 

time, EPA believes that SAR and QSAR can be most effectively utilized in the evaluation of 

chemicals that exhibit lower toxicity for human health and/or ecotoxicity parameters. This is 

appropriate because the risk assessment for lower toxicity chemicals can be stream-lined, i.e., a 

screening-level assessment procedure rather than multiple tiers of assessments with progressively 

more data requirements. 

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

Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) 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. Pre-submission consultation with the Agency is 

encouraged. 

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. Confirmation on the following label information: 

a. Sites of application 

b. Formulations 

c. Application methods and equipment 

d. Maximum application rates 

e. Frequency of application, application intervals and maximum number of 

applications 

f. Geographic limitations on use 

2. Use or potential use distribution 

3. Use history 

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

5. Typical application interval 

6. State or local use restrictions 

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

and mammalian mortalities) not already reported to the Agency 

8. Monitoring data 

Next Steps:

After the 60-day comment period closes in May 2011, the Agency will review and respond to 

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

Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) case. 

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II. Fact Sheet 

Background Information:

• Active Ingredient: Tetrakis(hydroxymethyl) phosphonium sulfate (THPS) 

• Case number: 5034 

• PC Code: 129058 

• CAS number: 55566-30-8 

• Technical registrants: Dow Chemical Co, Rhodia Inc 

• First approved for use in a registered product: 1995 

• There are no registered tolerances or exemptions from the requirement of a tolerance for 

this chemical. The Agency did not identify any FDA clearances for this chemical. 

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

blair.eliza@epa.gov

• Antimicrobials Division Product Manager (PM): Marshall Swindell, 

swindell.marshall@epa.gov

 

Use & Usage Information:

• The first product containing tetrakis(hydroxymethyl) phosphonium sulfate (THPS) as an 

active ingredient was registered in the United States in 1995. Currently 15 products 

containing tetrakis(hydroxymethyl)phosphonium sulfate (THPS) are registered. The 

chemical is registered for use as a materials preservative in paperboard manufacturing, 

coatings, pigments, emulsions and solutions, and fire protection systems. The products 

are also registered for antifoulant use in recirculating industrial process and water 

systems and oilfield recovery operations (drilling muds, packer fluids, pipeline pigging 

and scraping, and hydrotesting, among other applications). There are no pesticide 

tolerances or exemptions from the requirement of a tolerance for this chemical. 

Recent/Pending Regulatory Actions:

• There are no recent or pending regulatory actions for this chemical.

Ecological Risk Assessment Status:

Please refer to Scoping Document: Product Chemistry/Environmental Fate/Ecotoxicity of 

Tetrakis (hydroxymethyl) Phosphonium Sulfate, located in the docket, for a detailed discussion of 

the ecological risk assessments. 

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• The most recent ecological risk assessment was performed in 1995 in support the initial 

registration of a product containing THPS. 

• THPS appears to be stable and persistent under abiotic conditions at pHs 5, and 7 with 

half lives greater than 30 days. However, at pHs above 8 (basic conditions), it degrades 

within 7 days. The degradation products have been identified as trishydroxymethyl 

phosphine (THP) and subsequently trishydroxymethyl phosphine oxide (THPO). An open 

literature study also shows that THPS degrades in artificial seawater (ph 7.9) with a half 

life of 6 days. EPA’s EPI Suite model indicates that THPS is easily biodegradable (fast 

biodegradability); ultimate biodegradability is fast as well. Primary biodegradation half 

life is estimated at hours/days. 

• Its estimated Log Kow varies from -4.42 to -20.39; it is not likely to bioaccumulate in 

aquatic organisms. It does not appear to be persistent in air as its estimated half life 

(measured against hydroxyl radical) is less than 5 hours. The major uses of this pesticides 

are outdoor, and because it is hydrolytically stable, a number of environmental fate 

studies are triggered as the exposure from these uses will be in soils and water. Leaching 

and adsorption/desorption studies will clearly show if the chemical easily migrates into 

the soils and sediments and Kd values determined from adsorption/desorption studies will 

show if the binding with soils is strong or weak. Metabolism studies and 

biodegradability will show if the pesticide degrades in actual environmental medium. 

• THPS has been determined to show moderate acute toxicity to estuarine/marine 

organisms like Mysid Shrimp as well as to bivalves. THPS shows slight to moderate 

acute toxicity to Bluegill Sunfish and Rainbow Trout while it is only slightly toxic to 

Sheephead Minnow. For Avian Toxicity Testing, it shows moderate oral toxicity to 

Mallard Duck while only slight dietary acute toxicity is observed with Mallard Duck and 

Bobwhite Quail. 

Human Health Risk Assessment Status:

The following are key findings of the recent human health risk assessments for 

Tetrakis(hydroxymethyl)phosphonium sulfate (THPS). Please refer to Summary of Human 

Health Effects Data for the THPS Registration Review Decision Document, located in the 

docket, for a detailed discussion of the human health risk assessment. 

Hazard Characterization: 

• The most recent human health risk assessment was performed in 1995 in support the 

initial registration of a product containing THPS. 

• The Agency believes that THPS may be a formaldehyde releaser, because it contains a 

hydroxymethyl group, which is essential for the production of formaldehyde; 

additionally, the degradation products observed in an aquatic medium are 

trihydroxymethyl phosphine (THP) molecules, which are formed by releasing two 

formaldehyde (HCHO) molecules. 

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• The Agency does not have the emissions (e.g. air chamber) data to estimate potential 

concentrations of formaldehyde released in to air under various conditions. The Agency 

will likely need further data to determine the extent of the THPS degradation in air to 

form formaldehyde and THP. If EPA identifies that THPS is in fact a formaldehyde 

releaser, EPA may also need to develop additional inhalation risk assessments to assess 

the contribution of formaldehyde to the overall aggregate risk from all sources. 

Dietary (Food and Water): 

• THPS is most often used as a microbiocide/slimicide that is used to control bacteria, 

fungi, and algae in the manufacture of paper and paperboard products and adhesives that 

do not contact food. However, some end use products can also be used on emulsions that 

are applied to food-contact paper and paperboard. Therefore, indirect dietary exposure to 

food could be expected based on the use. Although likely to be infrequent, dietary 

exposures via drinking water may occur and assessments will be needed based on release 

to surface water from recirculating cooling towers. Upon receipt and review of the 

environmental fate data the Agency anticipates requiring, the Agency will determine the 

need for a down-the-drain drinking water assessment. 

Residential: 

• Residential handler exposure (dermal and inhalation) can occur through the application of 

THPS preservative coatings via paintbrush/roller or sprayer application for painting. 

Because these exposures are likely to be brief, the Agency expects to conduct residential 

handler risk assessments for these scenarios of only short-term duration (1-30 days). 

• There also may be residential post-application inhalation exposure to the degradate 

formaldehyde for these brush/roller and airless sprayer application methods. 

Aggregate:

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

information concerning exposures to pesticide residues in food and drinking water, as 

well as non-occupational pesticide exposures. The Agency expects to conduct an 

aggregate risk assessment that will include residential, dietary and drinking water 

exposures. 

Occupational: 

• Assessments of occupational risk are planned for registration review because potential 

exposure is expected through dermal and inhalation routes during open pour/pump liquid 

applications for the uses in industrial processes and water systems uses and material 

preservative uses. Some products’ use in pigments and coatings strongly implies that 

THPS may be used in paints; thus, the Agency will need to assess this use. 

• Both occupational and residential application techniques typically associated with 

painting exposures (pump/pour liquids, brush/roller, and airless sprayer) will be assessed 

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using the labeled rates typically used to preserve the water based coatings, pigments, and 

slurries. EPAwill assess residential handler exposure to paints assessing applications to 

brush/roller and airless sprayer for both short-term and intermediate-term durations. 

• There also may be occupational inhalation exposure to the degradate formaldehyde for 

these brush/roller and airless sprayer application methods. Other post-application 

inhalation exposures to THPS or from formaldehyde for uses such as oil drilling are 

expected to be minimal. Dermal post-application exposures for water-treatment and other 

material preservation uses such as paper manufacturing or oil drilling are likely to be 

minimal for THPS or formaldehyde. 

Cumulative: 

• EPA does not have, at this time, available data to determine whether THPS has a 

common mechanism of toxicity with other substances or how to include this pesticide in 

a cumulative risk assessment. For the purposes of this Registration Review, EPA has 

assumed that THPS does not have a common mechanism of toxicity with other 

substances.

Incidents:

Ecological: 

• No THPS ecological incidents have been reported in the OPP Incident Database System 

(IDS). 

Human Health: 

• There has been one reported human incident in the OPP Incident Database System (IDS) 

that has been associated with exposure to THPS and appears to be a result of a misuse. 

No further information was available on this incident. 

Tolerances and International Harmonization: 

• There are no tolerances or exemptions from tolerances for this chemical. 

Data Call-In Status:

• No Data Call-In (DCI) has been issued for this chemical. 

Labels: 

Registered active products, including EPA registration numbers are provided in Table 1 below. 

For future reference, during registration review a list of product registration numbers will be 

included in the docket. Product registration labels may be obtained from the Pesticide Product 

Label System (PPLS) website at: http://oaspub.epa.gov/pestlabl/ppls.home. 

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Table 1. Registered Active Products – THPS 

EPA Reg. 

Number 

Product Name Formulation Type % Active 

Ingredient 

Registrant 

464-8129 CYPHOS B1 

PHOSPHONIUM 

SALT 

Formulation 

Intermediate 

77.6 Dow Chemical 

Co. 

464-8127 AQUA THPS 75FW Ready-to-Use 

Solution

76.6 Dow Chemical 

Co. 

464-8126 AQUATHPS 75 Ready-to-Use 

Solution 

76.5 Dow Chemical 

Co. 

33677-3 TOLCIDE PS75 Formulation 

Intermediate 

75 Rhodia UK, Ltd 

33677-7 TOLCIDE PS75LT Ready-To-Use 

Solution 

75 Rhodia UK, Ltd 

4564-20 TOLCIDE PS70A Soluble Concentrate 70 Rhodia, Inc. 

4564-19 TOLCIDE PS70FA Flowable Concentrate/ 

Formulation 

Intermediate 

70 Rhodia, Inc 

4564-RA TOLCIDE PS355A Soluble Concentrate 35 Rhodia UK, Ltd 

10707-57 MAGNACIDE 575S Water-Soluble 

Packaging 

50 Baker Petrolite 

Corp 

4564-17 TOLCIDE PS50A Soluble Concentrate 50 Rhodia Inc. 

33677-5 TOLCIDE PS352C Ready-To-Use 

Solution 

35 Rhodia UK Ltd 

4564-18 TOLCIDE PS20A Soluble Concentrate 20 Rhodia Inc. 

4564-15 TOLCIDE PS200 Ready-to-Use 

Solution 

20 Rhodia Inc. 

82932-1 ALL CLEAR Soluble Concentrate 3 KIDDE Fire 

Fighting 

86130-2 FLOWCHEM FCAF001 Flowable Concentrate 20 Flowchem 

Technologies 

 

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III. Summary of Anticipated Data Requirements – Tetrakis(Hydroxymethyl)Phosphonium 

Sulfate (THPS) 

The table below summarizes anticipated data needs for the 

Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) Case in Section I of this document 

(Preliminary Work Plan), Scoping Document: Product Chemistry/Environmental 

Fate/Ecotoxicity of Tetrakis (hydroxymethyl) Phosphonium Sulfate, and Summary of Human 

Health Effects Data for the THPS Registration Review Decision Document. 

Table 2. Summary of Anticipated Data Requirements – THPS 

Guideline 

Number Anticipated Data Requirement Test Material 

Est. Timeframe (months) 

(Measured from DCI 

Receipt) 

870.3465 90-day inhalation toxicity (rat) TGAI, MP 24 

875.1100 Dermal outdoor exposure TGAI, MP 12-24 

875.1200 Dermal indoor exposure TGAI, MP 12-24 

875.1300 Inhalation outdoor exposure TGAI, MP 12-24 

875.1400 Inhalation indoor exposure TGAI, MP 24 

875.1600 Application exposure data 

reporting and calculations TGAI, MP 12 

875.1700 Product use information TGAI, MP 12 

875.2500 Inhalation exposure TGAI, MP 24 

875.2700 Product use information TGAI, MP 12 

875.2900 Data reporting and calculations TGAI, MP 24 

835.2240 Photodegradation in water TGAI, MP 12 

835.1230 Sediment and soil 

adsorption/desorption TGAI, MP 12 

835.1240 Leaching and 

adsorption/desorption TGAI, MP 12 

835.4300 Aerobic aquatic metabolism TGAI, MP 24 

835.4400 Anaerobic aquatic metabolism TGAI, MP 24 

835.3110 Ready Biodegradability TGAI, MP 24 

850.1010 Aquatic invertebrate acute toxicity, 

freshwater daphnids TGAI, MP 24 

17 
Docket Number: EPA-HQ-OPP-2011-0067 

www.regulations.gov

18 

850.1300 Daphnid chronic toxicity TGAI, MP 12 

850.1350 Mysid chronic tox - aquatic 

invertebrate life-cycle (saltwater) TGAI, MP 12 

850.4400 Aquatic plant toxicology test using 

Lemna spp., Tier I TGAI, MP 12 

850.1400 Fish early-life stage toxicity test 

(freshwater) TGAI, MP 12 

850.5400 Algal Toxicity Tier I and Tier II TGAI, MP 12