United States Chemical Safety September 2011

Environmental Protection and Pollution Prevention

Agency (7510P)

Tetrakis(Hydroxymethyl)Phosphonium Sulfate 

(THPS)

Registration Review:

Final Work Plan

September 2011

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

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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

________________________________________

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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Introduction

This is the Final Work Plan (FWP) of the Environmental Protection Agency (EPA or “the 

Agency”) for the registration review of Tetrakis(hydroxymethyl)phosphonium sulfate (THPS)

(Case 5034). The work plan includes the expected registration review timeline. The work plan 

also addresses public comments received concerning the Preliminary Work Plan (PWP) in the 

Summary Document which was posted in the Tetrakis(hydroxymethyl)phosphonium sulfate 

(THPS) registration review docket, and any other comments concerning the initial docket 

postings. The Summary Document provided information on what EPA knows about the pesticide 

and what additional risk analyses and data or information the Agency believes are needed to 

make a registration review decision.

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

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 that 

statutory standard. The public phase of registration review begins when the initial docket is 

opened for each case. Information on this program is provided at: 

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

The Tetrakis(Hydroxymethyl)Phosphonium Sulfate (THPS) Preliminary Work Plan (PWP) (PC 

Code 129058) was published on March 30, 2011 and the 60-day comment period ended on May 

31, 2011. The Preliminary Work Plan document is available on www.regulations.gov docket 

number EPA-HQ-OPP-2011-0067.

The first product containing Tetrakis(hydroxymethyl)phosphonium sulfate (PC Code 129058) as 

an active ingredient was registered in the United States in 1995. Currently, there are 15 products 

containing THPS registered with EPA. The pesticide is currently used as a materials preservative 

in paperboard manufacturing, and emulsion and solution preservation in addition to fire 

protection systems. The chemical also has industrial process and water systems uses in oil field 

and petrochemical areas. There are no inert uses associated with this chemical. There are no 

tolerances for this chemical.

The Agency believes that THPS may release formaldehyde. According to a recent EPA review

(more information in “Revised Summary of Human Health Effects Data for the THPS 

Registration Review Decision Document”, dated 9/21/2011), the formula of this chemical is such 

that it is likely to release formaldehyde because it contains hydroxymethyl group, which is an 

essential component in the production of formaldehyde, and the degradation products in aquatic 

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

formaldehyde (HCHO) molecules.

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

of formaldehyde released into the air under various conditions. The Agency will likely need data 

to determine the extent of the THPS degradation in air to form formaldehyde and THP. If the 

Agency identifies that THPS is in fact a formaldehyde releaser, EPA may also need to develop 
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additional inhalation risk assessments to assess the contribution of formaldehyde to the overall 

aggregate risk from all sources. 

Comments Received on the Preliminary Work Plan

The Agency received comments from three sources during the public comment period on the 

initial docket, described below. In the PWP, the Agency solicited comments on four specific 

topics: environmental justice, water body impairment, trade irritants, and structure activity 

relationships. The Agency received no comments during the public comment period concerning 

those four issues. This document makes final the work plan for the 

Tetrakis(hydroxymethyl)phosphonium sulfate (THPS) registration review process.

Comment:

The FIFRA Endangered Species Task Force (FESTF) submitted a comment noting that it has 

data that will assist the Agency in conducting an endangered species risk assessment for THPS, 

and requesting that any technical registrant for THPS who is not a member of the FESTF (or a 

company having met its data compensation obligations) be asked to provide a formal offer-topay to FESTF for reliance on their data.

Response:

The Agency thanks FESTF for its comment and will consider this information as it conducts the 

registration review and makes its registration review decisions.

Comment:

There are several errors in the mentioned use patterns for THPS. THPS is an industrial 

antimicrobial targeted for use in various industrial process water use sites (oilfield production 

and stimulation, cooling towers, and paper mills, etc). THPS is not used as an in-can preservative 

in any paint applications, nor was this use ever envisioned due to the ineffectiveness of THPS in 

these applications. However, we do concede that such a use may be construed from current label 

language, and Rhodia offers to include a new statement on our labels prohibiting such use, e.g. 

“not for use in paint”.

Elsewhere, THPS is mentioned as a leather preservative, but Rhodia believes this also to be 

inappropriate. THPS is used as a leather tanning agent in some parts of the world (e.g. Asia, 

etc.), but this involves a chemical “tanning” reaction, not a biocidal application, and thus does 

not belong in this assessment.

Rhodia also has no customer uses for THPS as a wood preservative. Rhodia has not examined 

the use of THPS as a wood preservative, and we do not believe it is ever used in this application 

area. Rhodia believes reference to use of THPS in wood preservation is inappropriate.

Finally, Rhodia-manufactured THPS is not marketed for use in surface disinfectants and there 

are no claims on our manufacturing- or end-use labels for such uses.
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Response:

The human health assessment does not mention the use of THPS as a wood preservative or 

surface disinfectant. We have deleted an erroneous entries to leather uses found in the Appendix. 

Based on the manufacturing use as a preservative in water based coatings, pigments, and slurries, 

we construed the use to be paint. When the label is changed to reflect the "not for use in paints" 

statement, EPA will revise the THPS human health assessment, removing paint data 

requirements and assessments.

Comments on Handler Data Requirements& Risk Assessments:

EPA lists the following studies as being data gaps based on the use of THPS in paints:

o 90-day inhalation toxicity study (Series 870.3465)

o Dermal Exposure (outdoor and Indoor) (GDLN 875.1100 and 875.1200)

o Inhalation exposure (Outdoor and Indoor) (GDLN 875.1300 and 875.1400)

o Data Reporting and Calculations (GDLN 875.1600) )

o Product Use Information (GDLN 875.1700)\

Most applications of THPS are expected to be made with automated dosing pumps, but some 

applications by open pour may occur. Rhodia is part of the Antimicrobial Exposure Assessment 

Task Force II (AEATFII) that is planning to conduct a monitoring study to look at open pour 

exposures (dermal and inhalation). Rhodia would be able to provide this data when the study is 

complete, if it is required by EPA.

Response:

Should the registrant(s) revise(s) the labels with the new label statement "not for use in paints", 

the Agency anticipates that only an occupational dermal risk assessment for the open 

pour/pump liquid applications for the uses in industrial processes and water systems uses and 

material preservative uses would be needed. 

Thus, the Agency would expect that the anticipated 90-day inhalation toxicity data (Series 

870.3465) need based on the paint use would be eliminated in this case. Likewise, should the 

paint use be deleted, the Agency would expect that the anticipated inhalation exposure 

requirements (GDLNs 875.1300 and 875.1400) would also be eliminated in this case.

Comments on Postapplication Risk Assessments & Data Requirements:

THPS is not used in paints and Rhodia plans to add labeling to clarify “not for use in paints”. 

Given this, exposure studies and a post-application risk assessment for THPS linked to use in 

paint should not be necessary.

Response:

The registrant is correct in stating what a consequence would be once it revises its labels to 

include a new label statement "not for use in paints". Once that change is final and effective, the 

Agency would expect that the postapplication exposure data requirements and postapplication 
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exposure assessments will longer be required for this case based on the other use patterns. As 

such, once the change to the label is final and effective, the Agency would expect to no longer 

need the following data:

o (GDLN 875.2500) Inhalation exposure

o (GDLN 875.2700) Product Use Information and

o (GDLN 875.2900) Data reporting and calculations

Comments on Residential Risk Assessment:

A residential risk assessment should not be required for THPS as residential use is not 

anticipated. An occupational risk assessment for paint applicators should also not be necessary as 

THPS is to our knowledge not used in paint.

Response:

Once the registrant(s) revises the labels with the new label statement "not for use in paints", the 

Agency expects that residential risk assessments would no longer be required for THPS since 

paint application is the only use that would trigger a residential assessment. All of the paintrelated occupational risk assessments would also no longer be expected to be required once the 

aforementioned label change is final and effective.

Comment:

It is stated in the workplan in several locations that no earlier risk assessments have been 

conducted. This appears to be an error, as the indirect food use of THPS as a slimicide in paper 

mills producing food contact paper and paperboard has been assessed by FDA (21CFR176.300) 

and EPA (D257896 + MRID# 45542001). More recently an assessment has been completed by 

FDA (FCN 955) for use of THPS as a preservative in slurries that may be used in paper and 

paperboard coatings.

Response:

The registrant is correct that in the human health assessment conducted for the preliminary work 

plan, we acknowledge that an earlier dietary risk assessment was conducted. The final work plan 

reflects this.

Note: Registrants citing an FDA dietary risk assessment for paper and paperboard are 

encouraged to submit the full reference to the Agency so that it can be located and 

incorporated into the THPS Registration Review risk assessment.

Comment:

The registrant submitted ecological/environmental fate data over a decade ago that would satisfy 

some of the data requirements in this work plan.
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Response:

If registrants believe they have submitted data that could satisfy the anticipated data requirement,

registrants are encouraged to cite MRIDs either prior or in response to the Data Call-In expected 

to be issued for this case, and the Agency will review them for adequacy.

Comment:

The biocide industry is concerned about the use of the term “formaldehyde releaser” with respect 

to THPS. 

Response:

The Agency uses this term merely to note that the potential exists for the release of formaldehyde 

from a particular biocide. It does not necessarily imply that in all cases the release of 

formaldehyde is a risk concern. If data exist for a particular biocide which shows that the level of 

release of formaldehyde is low, then in many cases the Agency will not have any concerns. The 

explanation and scientific information provided by the registrants indicates that formaldehyde 

release from THPS will be low; however, the hydrolysis study the Agency anticipates requiring 

will characterize the amount.

Comment:

The Agency has listed the solubility of THPS in organic solvents as a data gap. However, as noted 

for aqueous solubility data, THPS is manufactured in situ as an aqueous solution. The material is 

therefore not isolated in a form suitable for solubility testing. 

Response:

The Agency accepts the rationale for not asking solubility in organic solvents, and will remove it 

from the data requirements list.

Additional Changes to the Final Work Plan and Associated Documents

The Preliminary Work Plan incorrectly stated that no prior dietary risk assessment had been 

performed. A dietary risk assessment was conducted during registration to examine the indirect 

food use exposures for food contact paper and paper board. According to the dietary risk 

assessment, the Agency concluded that dietary risks were acceptable. Although a dietary risk 

assessment has been done during registration, the Agency will likely reevaluate the indirect food 

uses (e.g. paper and paperboard, water based coatings, pigments, etc.) and exposures and 

toxicological endpoints and conduct a new acute and chronic dietary assessment during 

registration review.

Additionally, it was discovered that an end-use registrant has a new registered use on its THPS 

labels - sanitizers and disinfectants - for which no additional data were required at the time of 

registration. This use is not supported by the technical registrants of THPS; therefore, the enduse registrant, Kidde Fire Fighting, will need to submit the sanitizers and disinfectants data 
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listed below when required to do so by a data call-in notice or amend their THPS labels to 

remove this use. A revised Human Health Scoping Document for THPS has also been posted 

incorporating the expanded anticipated risk assessment and data needs for this 

sanitizer/disinfectant use.

• (GDLN 875.2300) Indoor Surface Residue Dissipation

• (GDLN 875.2700) Product Use Information (for 875.2300)

• (GDLN 875.2900 Data Reporting and Calculations (for 875.2900)

Risk Assessments and Anticipated Data Needs

The Agency will conduct a comprehensive ecological risk assessment, including an endangered 

species risk assessment, for all uses of THPS. The Agency will conduct a human health risk 

assessment. The Agency expects to require additional data for use in conducting the registration 

review for THPS.

Ecological Risk Assessment Status and Data Needs

• No ecological risk assessment has been performed for THPS.

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

conducting the registration review of THPS.

GLN 850.1010 -- Aquatic invertebrate acute toxicity, freshwater daphnids

GLN 850.1300 -- Daphnid chronic toxicity test

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

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

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

GLN 850.5400 -- Algal Toxicity Tier I and Tier II

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

for use in conducting the registration review of THPS.

GLN 835.2240 -- Photodegradation in water

GLN 835.1230 -- Sediment and soil adsorption/desorption

GLN 835.1240 -- Leaching and adsorption/desorption

GLN 835.4300 -- Aerobic aquatic metabolism

GLN 835.4400 -- Anaerobic aquatic metabolism

GLN 835.3110 -- Ready Biodegradability

• 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 Assessment Status and Data Needs

• No recent full human health risk assessment has been performed for THPS. A dietary risk 

assessment was performed at the time of registration in 1995.
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Dietary Assessment

• THPS is used as a microbiocide/slimicide and is registered for use to control bacteria, fungi, 

and algae in the manufacture of paper and paperboard products and adhesives that do not 

contact food. Some end use products are also registered for use in emulsions that are applied 

to food-contact paper and paperboard. Therefore, indirect dietary exposure to food could be 

expected based on the latter use. An FDA tolerance was not identified. Dietary exposures via 

drinking water may occur and assessments will be needed based on the use in recirculating 

cooling towers and potential release of water containing THPS residues to surface water. 

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.

• A dietary risk assessment was conducted during registration to examine the indirect food use

exposures from the food contact paper and paper board uses. According to the dietary risk 

assessment, EPA concluded that dietary risks were acceptable. Although a dietary risk 

assessment has been done during registration, EPA will likely reevaluate the indirect food 

uses (e.g. paper and paperboard, water based coatings, pigments, etc.) and exposures and 

toxicological endpoint and conduct a new acute and chronic dietary assessment during 

registration review. 

Tolerances and International Harmonization

• There are no tolerances for this chemical. However, it should be noted that a food contact 

substance notification (FCN No. 955) was submitted by the registrant to FDA on 

6/17/2010 to allow THPS at levels not to exceed 400 ppm in water based coatings, 

starches, pigments, and filler substances. THPS is also listed by FDA in 21 CFR 

§176.300 as a slimicide in paper/paperboard at a maximum use level of 84 mg/kg in the 

pulp slurry. The additive may also be added to water, which when introduced into the 

pulp slurry, results in a concentration in the pulp slurry not to exceed 84 mg/kg. The 

EPA-registered labels with paper and paperboard uses state that the concentrations of 

THPS in the registered paper and paperboard products cannot exceed 84 ppm.

Occupational and Residential Assessment and Risk

• Based on the available use information, the Agency believes that there is potential exposure 

to occupational handlers from open pour/pump liquid applications for the uses in industrial 

processes and water systems uses and material preservative uses. In addition, since THPS is 

found as a material preservative in water based coatings, pigments and slurries, EPA assumes 

that THPS could also be used as an in-can preservative in paints even though this application 

is not stated in the existing registered labels. Currently the label does not prohibit this use. If 

painting use is prohibited, the Agency anticipates that some data will not be needed. 

• Until labels prohibit the paint use, the Agency will continue to assume THPS is used in

paints. Therefore, both occupational and residential application techniques typically 

associated with painting exposures (pump/pour liquids, brush/roller, and airless sprayer) will 

be assessed using the labeled rates typically used for similar chemicals to preserve the water 
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based coatings, pigments, and slurries. The Agency will assess residential handler exposure 

to paints assessing applications to brush/roller and airless sprayer. 

• Product use data provided by the registrant will be useful to clarify whether THPS added to 

water based coatings, pigments, and slurries are later formulated into paints. Based on 

product use data, the Agency may later decide to refine the risk assessment scenarios and to 

refine exposure assessment assumptions. If label prohibitions on paint use are put into effect 

then the Agency anticipates that painting exposure data will not be necessary.

• If THPS is used to manufacture paints, the Agency anticipates that it may need to perform an 

inhalation occupational and residential post-application exposure assessment for the 

degradate formaldehyde. Other inhalation post-application exposures to THPS or from 

formaldehyde for uses such as oil drilling are expected to be minimal. Dermal postapplication exposures for water-treatment and other material preservation uses such paper 

manufacturing or oil drilling are likely to be minimal for THPS or formaldehyde.

• Residential Handlers*: Residential handler exposure (dermal and inhalation) can occur 

through the application of THPS-preserved coatings via paintbrush/roller or sprayer 

application for painting. The Agency expects to conduct residential handler risk assessments 

for these scenarios.

* Note that if the material preservatives used in coatings, pigments and slurries are prohibited 

for the use in paint products, the Agency anticipates that painting exposure data will not be 

necessary.

Aggregate and Cumulative Exposure and Risk

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

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

non-occupational pesticide exposures. The Agency expects to conduct an aggregate risk 

assessment that will include residential, dietary and drinking water exposures.

• Unlike other pesticides for which EPA has followed a cumulative risk approach based on a 

common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding 

as to THPS and any other substances. 

• The Agency believes that THPS may release formaldehyde. According to the human health 

scoping document which may be found in the docket for this Registration Review case,

(more information in “Revised Summary of Human Health Effects Data for the THPS 

Registration Review Decision Document”, dated 9/21/2011), the formula of this chemical is 

such that it is likely to release formaldehyde because it contains hydroxymethyl group, which 

is an essential component in the production of formaldehyde, and the degradation products in 

aquatic medium are trihydroxymethyl phosphine (THP) molecules which are formed by 

releasing two formaldehyde (HCHO) molecules.

• If the required hydrolysis study reveals that formaldehyde is being released in quantities of 

concern, the Agency will incorporate this into its cumulative assessment of formaldehyde 
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and THPS. For information regarding EPA’s efforts to determine which chemicals have a 

common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see 

the policy statements released by EPA’s Office of Pesticide Programs concerning common 

mechanism determinations and procedures for cumulating effects from substances found to 

have a common mechanism on EPA’s website at http://www.epa.gov/pesticides/cumulative/.

Human Health Data Needs

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

use in conducting the registration review of THPS.

GLN 870.3465 -- 90-day inhalation toxicity (rat)

GLN 875.1100 -- Dermal outdoor exposure

GLN 875.1200 -- Dermal indoor exposure

GLN 875.1300 -- Inhalation outdoor exposure

GLN 875.1400 -- Inhalation indoor exposure

GLN 875.1600 -- Application exposure data reporting and calculations (for 875.1100-

1400)

GLN 875.1700 -- Product use information (for 875.1100-1400)

• If sufficient quantities of THPS degradates such as formaldehyde are identified in a 

hydrolysis study, the Agency may also need air monitoring data and, if so, would expect to 

require the following data for use in examining THPS and formaldehyde inhalation exposure. 

The studies anticipated as needed would be:

GLN 875.2500 -- Inhalation exposure

GLN 875.2700 -- Product use information

GLN 875.2900 -- Data reporting and calculations

• Additionally, the end-use registrant with the disinfecting foam use on their label (EPA Reg. # 

82932-1) will need to submit the following studies in response to the data call-in in order to 

retain this use:

 GLN 875.2300 -- Indoor Surface Residue Dissipation

 GLN 875.2700 -- Product Use Information

GLN 875.2900 -- Data Reporting and Calculations

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

the THPS Registration Review Decision Document, dated August 9, 2011, located in the 

docket.

Product Chemistry Data Needs

• The Agency does not anticipate the need to require additional product chemistry data for this 

registration review at this time.
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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.

Incidents:

Ecological:

• No THPS ecological incidents have been reported in the Agency's Ecological Incident 

Information System (EIIS).

Human Health:

• There have been no human incidents in the OPP Incident Data System (IDS) that are 

associated with exposure to THPS.

Endangered Species

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.

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 for THPS, 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 
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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 call-ins, 

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:

Anticipated Schedule

Activities Estimated Month/Year

Phase 1: Opening the docket

Open Public Comment Period for Docket Completed

Close Public Comment Period for Docket Completed

Phase 2: Case Development

Develop Final Work Plan (FWP) September 2011

Issue DCI September 2012

Data Submission September 2014

Open Public Comment Period for Preliminary Risk Assessments March 2016

Close Public Comment Period for Preliminary Risk Assessments April 2016

Phase 3: Registration Review Decision

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

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

Final Decision and Begin Post-Decision Follow-up March 2017

Total (years) 6

Next Steps

A DCI will be developed regarding the anticipated data needs listed under the “Risk Assessments 

and Anticipated Data Needs” section of this document. The Agency expects to issue the DCI in 

September 2012. Human health and environmental fate and ecological hazard assessments will 

be conducted for all uses.