Docket Number: EPA-HQ-OPP-2010-0215 

www.regulations.gov 

Fosamine Ammonium Summary Document 

 Registration Review: Initial Docket 

 June 2010 
Registration Review Document for

Fosamine Ammonium

Case No. 2355

Approved By:

Gku--c~.p ,'»

Richard P. Keigwin, Jr., Director

Pesticide Re-evaluation Division

Date - I - .ac I D

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TABLE OF CONTENTS 

I. Preliminary Work Plan (PWP) 4 

II. Fact Sheet 10 

________________________________________ 

Please Note 

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

current position based on the following documents: 

1. Registration Review: Preliminary Problem Formulation for the Ecological Risk and 

Drinking Water Exposure Assessments for Fosamine Ammonium. May 19, 2010. 

2. Fosamine Ammonium. Human Health Assessment Scoping Document in Support of 

Registration Review. March 25, 2010. 

3. Fosamine Ammonium: Review of Human Incidents. February 25, 2010. 

4. Appendix A for Fosamine Ammonium. June 3, 2009.

Supporting documents for Fosamine Amonium may be found in the docket (EPA-HQ-OPP2010-0215) located on the internet at www.regulations.gov. 
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I. Preliminary Work Plan – Fosamine Ammonium 

Introduction:

The Food Quality Protection Act of 1996 mandated a registration review program. All pesticides 

sold or distributed in the United States (U.S) generally must be registered by the Environmental 

Protection Agency (EPA or the Agency), based on scientific data showing that they will not 

cause unreasonable risks to human health or the environment when used as directed on product 

labeling. The registration review program is intended to make sure that, as the ability to assess 

risk evolves and as policies and practices change, all registered pesticides continue to meet the 

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

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

registration review program, the Agency periodically reevaluates pesticides to make sure that as 

change occurs, products in the marketplace can be used safely. Information on this program is 

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

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

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

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

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

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

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

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

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

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

schedule for the registration review of fosamine ammonium. 

Fosamine ammonium is an herbicide registered for use on non-agricultural rights-of way, 

industrial sites, fencerows, pine plantations, and sewage disposal areas. Formulated as a water 

soluble liquid, fosamine ammonium functions as a plant growth regulator. There are no 

residential uses and no residential exposures from the registered uses are anticipated. Tolerances 

are not currently established for fosamine ammonium since there are no registered food or feed 

uses. Fosamine ammonium was first registered in 1975 and the reregistration eligibility decision 

(RED) was issued in 1995. 

Anticipated Risk Assessment and Data Needs:

The Agency anticipates conducting a comprehensive ecological risk assessment, including an 

endangered species assessment and updating the occupational exposure and risk assessment for 

all uses of fosamine ammonium and degradates of concern. A drinking water exposure and risk 

assessment is also anticipated in order to support registration review. Below is a summary of the 

issues relevant to the registration review process of fosamine ammonium. 
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Ecological Risk: 

• The most recent ecological risk assessment for fosamine ammonium was completed in 

1994 to support the RED. 

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

species determination for fosamine ammonium. The ecological risk assessment planned 

during registration review will allow the Agency to determine whether fosamine 

ammonium’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 Service (the Services), as appropriate. 

• Based upon the use pattern and fosamine ammonium’s current ecotoxicity and 

environmental fate database, the Agency anticipates requiring the following data in order 

to conduct a complete ecological risk assessment, including an endangered species 

assessment, for all uses: 

o GLN 850.2100 Avian acute oral toxicity study (passerine species) 

o GLN 850.1400 Fish early life-stage (freshwater) (Rainbow trout, Bluegill sunfish) 

o GLN 850.1300 Aquatic invertebrate life-cycle (freshwater) (Water flea) 

• Please refer to the document, Registration Review – Preliminary Problem Formulation 

for the Ecological Risk and Drinking Water Assessments for Fosamine Ammonium,

located in the docket for a detailed discussion of the anticipated risk assessment and data 

needs. 

Human Health Risk:

• The most recent human health risk assessment for fosamine ammonium was completed in 

1994 to support the RED. 

• A dietary (food only) exposure assessment is not anticipated for fosamine ammonium 

because there are no registered food or feed uses. However, a new drinking water 

exposure and risk assessment is anticipated for registration review. 

• Based on the registered uses, the Agency does not anticipate conducting a residential 

exposure assessment for this registration review of fosamine ammonium. 

• The Agency does not intend to conduct an aggregate risk assessment as there are no 

food/feed uses and no residential uses of fosamine ammonium. 
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• The most recent occupational exposure and risk assessments for fosamine ammonium 

were conducted in 1994 to support the RED. An updated occupational exposure and risk 

assessment, that incorporates updated assessment methodologies, will be conducted 

during this registration review. 

• Based on the current use pattern, the Agency anticipates requiring the following data in 

order to support a human health risk assessment for fosamine ammonium: 

o GLN 870.3465 90-Day Inhalation Toxicity (rat) 

o GLN 870.3700b Developmental Toxicity (rabbit) 

o GLN 870.7800 Immunotoxicity 

• Following submission of the additional toxicological data, the Agency plans to update the 

human health toxicity profile. 

• Please refer to the document, Fosamine Ammonium. Human Health Assessment Scoping 

Document in Support of Registration Review, located in the docket for a detailed 

discussion of the anticipated risk assessment and data needs for human health. 

Other Anticipated Data Needs: 

• GLN 830.7050 UV/Visible Light Absorption – this study is a new data requirement under 

40 CFR part 158 (Product Chemistry Data Requirements) for registration of a pesticide 

(food and non-food uses). The Agency anticipates requiring this study to obtain basic 

information about the compound’s identity/composition and the wavelengths at which the 

compound may be susceptible to photochemical degradation. 

Endocrine Disruptor Screening Program:

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

Screening Program (EDSP) to determine whether certain substances (including pesticide active 

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

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

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

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

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

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

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

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

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

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

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

group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. 

This list of chemicals was selected based on the potential for human exposure through pathways 
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such as food and water, residential activity, and certain post-application agricultural scenarios. 

This list should not be construed as a list of known or likely endocrine disruptors. 

Fosamine ammonium is not among the group of 58 pesticide active ingredients on the initial list 

to be screened under the EDSP. Under FFDCA sec. 408(p) the Agency must screen all pesticide 

chemicals. Accordingly, EPA anticipates issuing future EDSP orders/data call-ins for all 

registration review cases, including those for which EPA has already opened a registration 

review docket for a pesticide active ingredient. 

For further information on the status of the EDSP, the policies and procedures, the list of 67 

chemicals, the test guidelines and the Tier 1 screening battery, please visit our website: 

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

Timeline:

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

registration review. 

Registration Review for Fosamine Ammonium – Projected Registration Review Timeline

Activities Estimated Date 

Opening the docket 

Open Docket and Public Comment Period 2010 – June 

Close Public Comment 2010 – August 

Case Development 

Final Work Plan 2010 – November 

Issue DCI 2011 – July – Sept. 

Data Submission 2013 – July – Sept. 

Open Public Comment Period for Preliminary Risk Assessments 2015 – Jan. – March 

Close Public Comment Period 2015 – April - June 

Registration Review Decision 

Open Public Comment Period for Proposed Registration Review 

Decision 

 2015 – July - Sept. 

Close Public Comment Period 2015 – Oct. – Dec. 

Final Registration Review Decision and Begin Post-Decision Follow-up 2016 

Total (years) 6 

Guidance for Commenters:

The public is invited to comment on EPA’s preliminary registration review 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 fosamine 

ammonium. 
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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:

Fosamine ammonium 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 fosamine 

ammonium, 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 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 they 

can be used quantitatively or qualitatively in pesticide risk assessments. 

Environmental Justice:

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

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

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

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

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

atypical, unusually high exposure to fosamine ammonium, 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. 

Other Information:

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

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

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

1. suggestions from stakeholders on ways to reduce non-target organism exposures to 

fosamine ammonium 

2. confirmation on the following label information 
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a. maximum application rates in units related to mass per unit area of treatment 

zone 

b. geographic limitations on use 

3. use or potential use distribution (e.g., acreage and geographical distribution of use 

sites) 

4. use history 

5. median and 90th percentile reported use rates (lbs. a.i./acre) from usage data – 

national, state, and county 

6. application timing (date of first application and application intervals) by use site – 

national, state and county 

7. directly acquired county-level usage data (not derived from state level data) 

a. maximum reported use rate (lbs. a.i./acre) from usage data – county 

b. median and 90th percentile number of applications – county 

c. total pounds per year – county 

d. the year the pesticide was last used in the county/sub-county area 

e. the years in which the pesticide was applied in the county/sub-county area 

8. state or local use restrictions 

9. ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian 

and mammalian mortalities) not already reported to the Agency 

10. monitoring data 

Next Steps:

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

received in a timely manner, and then issue its Final Work Plan (FWP) for the fosamine 

ammonium registration review.
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II. FACT SHEET 

Background Information:

• Fosamine Ammonium PC Code: 106701, CAS#: 25954-13-6 

• Technical registrant: E.I. DuPont de Nemours and Co., Inc. (EPA No. 352) 

• First registered for use in 1975 

• Reregistration Eligibility Decision issued in December, 1995 

• There is one active FIFRA section 3 registration: EPA Reg. No. 352-395 

• Pesticide Re-evaluation Division Chemical Review Manager (CRM): Rusty Wasem 

wasem.russell@epa.gov

• Registration Division Contact: Eugene Wilson wilson.eugene@epa.gov 

Use & Usage Information: For additional details, please refer to the BEAD Appendix A 

document in the fosamine ammonium docket. 

• Fosamine ammonium is a non-food use herbicide registered for use on non-agricultural 

rights-of way, industrial sites, fencerows, pine plantations, and sewage disposal areas. 

• Fosamine ammonium is formulated as a water soluble liquid. 

• The Agency currently lacks data on the estimated nationwide use (in pounds) of fosamine 

ammonium. 

Recent Actions:

• There are no recent regulatory actions for fosamine ammonium.

Ecological Risk Assessment Status: 

The following are key findings of the most recent ecological risk assessments for fosamine 

ammonium. Please refer to the document, Registration Review – Preliminary Problem 

Formulation for the Ecological Risk and Drinking Water Assessments for Fosamine Ammonium, 

located in the docket for a detailed discussion of the ecological risk assessment. 

• Fosamine ammonium is classified as practically non-toxic to freshwater fish and 

invertebrates and estuarine/marine fish and invertebrates on an acute exposure basis. 

Fosamine ammonium is also classified as practically non-toxic to terrestrial invertebrates, 

mammals and birds on an acute exposure basis. 

• While fosamine ammonium is classified as slightly toxic to practically non-toxic to 

aquatic plants, applications of fosamine ammonium at the registered rates may pose a 

significant risk to endangered terrestrial plant species inhabiting treated rights-of-way. 

The Agency was unable to assess plant risks at the time of the RED due to lack of 

acceptable terrestrial plant data. Terrestrial plant toxicity data received since the RED 

will be reviewed during registration review to inform the potential risk of fosamine 

ammonium to endangered and non-endangered plant species. 
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• Previously completed risk assessments indicate that registered uses of fosamine 

ammonium do not produce risk quotients (RQs) that exceed the Agency’s level of 

concern (LOC) for animal species. Use of fosamine ammonium may, however, directly 

affect terrestrial plants, especially from the right-of-way use (RQs = 4 and 57 for seedling 

emergence and vegetative vigor, respectively), and through loss of food source, indirectly 

affect animals depending on terrestrial plants for food or habitat. Due to a short half-life 

(<4 days), chronic risks to aquatic organisms are not expected from registered uses 

of fosamine ammonium. 

Human Health Risk Assessment Status:

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

ammonium. Please refer to the document, Fosamine Ammonium. Human Health Assessment 

Scoping Document in Support of Registration Review, located in the docket for a detailed 

discussion of the human health risk assessment. 

Hazard Characterization: 

• Fosamine ammonium has low acute oral and inhalation toxicity and moderate dermal 

toxicity. It is not an acute dermal irritant or a dermal sensitizer. It is a moderate-to-severe 

eye irritant. 

• An acute neurotoxicity study in rats showed possible neurotoxic effects at the higher 

doses. A subchronic neurotoxicity study showed no evidence of neurotoxic effects. 

• The Agency has not received chronic oral toxicity or carcinogenicity studies for fosamine 

ammonium. The anticipated data requirement for a developmental toxicity study will 

inform the Agency about the possible chronic toxic effects of fosamine ammonium. 

Dietary (Food and Drinking Water): 

• Because fosamine ammonium has no food or feed uses, dietary exposure and risk were 

not estimated in the 1994 human health risk assessment. Dietary analysis (from drinking 

water) has not been previously performed.

Residential: 

• There are no residential uses for fosamine ammonium, therefore, a residential exposure 

risk assessment has not been conducted. 

Aggregate: 

• No aggregate exposure assessment had been previously performed because dietary 

exposure to fosamine ammonium was not expected and there are no residential uses.
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Occupational: 

• An occupational exposure assessment was last conducted for fosamine ammonium in 

1994 to support the 1995 RED. Toxicity endpoints for occupational exposures through 

dermal and inhalation pathways were not selected for the 1994 assessment because the 

toxicity endpoints from the available toxicity studies did not trigger risk concern based on 

expected exposure (i.e., the No Observed Effect Levels were considered sufficiently 

high). 

• Occupational post-application exposure and risk has not been quantitatively assessed 

because the potential for post-application exposure to fosamine ammonium residues was 

determined to be low based on use patterns.

• A quantitative assessment of risk to handlers was determined to be unnecessary since a 

qualitative review of results of acceptable toxicity studies combined with expected 

exposure did not trigger risk concerns. 

• Past fosamine ammonium risk assessments rely in part on data from studies in which 

adult human subjects were intentionally exposed to a pesticide to determine their dermal 

and inhalation exposure. Many such studies, involving exposure to many different 

pesticides, comprise generic pesticide exposure databases such as the Pesticide Handlers 

Exposure Database (PHED) and the Agricultural Reentry Task Force (ARTF) Database. 

EPA has reviewed all the studies supporting these multi-pesticide generic exposure 

databases, and has found no clear and convincing evidence that the conduct of any of 

them was either fundamentally unethical or significantly deficient relative to the ethical 

standards prevailing at the time the research was conducted. All applicable requirements 

of EPA’s Rule for the Protection of Human Subjects of Research (40 CFR Part 26) have 

been satisfied, and there is no regulatory barrier to continued reliance on these studies. 

Cumulative:

• The Agency has not determined whether fosamine ammonium shares a common 

mechanism of toxicity with other chemical substances. If, in the future, the Agency 

determines that new information on fosamine ammonium is available that could 

potentially impact a cumulative risk assessment and result in a risk of concern, the 

Agency will revisit a cumulative risk assessment. 

Incidents:

• The Office of Pesticide Programs Incident Data System (IDS) was reviewed for reports 

of fosamine ammonium human incidents. No human incidents have been reported from 

2002 to the present associated with the use of fosamine ammonium. 

• A preliminary review of the Ecological Incident Information System (EIIS) indicated one 

terrestrial plant incident that has been classified as “possibly” caused by fosamine 
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ammonium use and, The American Bird Conservancy database did not list any incidents 

associated with fosamine ammonium use. 

Data Call-In (DCI) Status:

• DCI’s were issued for fosamine ammonium as part of the reregistration process, and all 

data requirements have been satisfied. 

Tolerances and International Harmonization: 

• There are no food or feed uses for fosamine ammonium. Therefore, no tolerances have 

been established for this pesticide.

Labels: 

• The label for fosamine ammonium (EPA Reg. No. 352-395) can be obtained from the 

Pesticide Product Label System (PPLS) website: 

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