Docket Number: EPA-HQ-OPP-2010-0783 

www.regulations.gov 

Summary Document for Sodium Asulam 

 Registration Review: Initial Docket 

 March 2011 

 

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TABLE OF CONTENTS 

I. Preliminary Work Plan (PWP) 4 

II. Fact Sheet 11 

________________________________________ 

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 Environmental Fate and 

Ecological Risk, Endangered Species, and Drinking Water Assessments for Asulam and 

Sodium Asulam. December 22, 2010 

2. Asulam: Human Health Risk Scoping Document in Support of Registration Review. 

January 5, 2011 

3. Asulam and Sodium Asulam: Review of Human Incidents. November 30, 2010 

4. BEAD Chemical Profile for Registration Review on Asulam, Sodium Salt. December 2, 

2010 

5. Appendix A for Sodium Asulam. June 25, 2010

Supporting documents for sodium asulam may be found in the docket (EPA-HQ-OPP-2010-

0783) located on the internet at www.regulations.gov. 
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I. Preliminary Work Plan – Sodium Asulam 

Introduction:

The Food Quality Protection Act (FQPA) 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 sodium asulam (“asulam” unless otherwise specified). 

Asulam is a selective, systemic, postemergent, carbamate herbicide used to control a variety of 

annual grasses and broadleaf weeds on sugarcane, Christmas tree plantations, ornamentals, turf 

(for sod only) and non-cropland areas (boundary fences, fencerows, hedgerows, lumberyards, 

storage areas and industrial plant sites, and warehouse lots). In addition, asulam is used on 

spinach grown for seed in Washington and Oregon under Special Local Needs Registrations that 

were issued in 2008. Asulam has no registered residential uses. The only end-use formulation of 

asulam is a soluble/concentrate liquid (sodium salt of asulam). Tolerances have been established 

for residues of asulam in/on sugarcane and livestock commodities (40 CFR §180.360). Asulam 

acts by inhibiting cell division in plants. Asulam was first registered in 1975. The reregistration 

eligibility decision (RED) was issued in 1995 and the tolerance reassessment eligibility decision 

(TRED) was issued in 2002. 

Anticipated Risk Assessment and Data Needs:

The Agency anticipates conducting a comprehensive ecological and human health risk 

assessment, including an endangered species assessment. Below is a summary of the issues 

relevant to the registration review of asulam. 
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Ecological Risk: 

• The most recent ecological risk assessment for asulam was completed in 1995 to support 

the RED. 

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

species determination for asulam. The ecological risk assessment planned during 

registration review will allow the Agency to determine whether asulam’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 asulam’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 test (passerine species) 

o GLN 850.4100, 4150 – Terrestrial plant toxicity tests (using TEP)(Tier II) 

o GLN 850.2300 – Avian reproduction 

o GLN 850.1350 – Aquatic invertebrate life cycle (freshwater) 

o GLN 850.1400 – Fish early life stage (freshwater) 

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

for Environmental Fate and Ecological Risk, Endangered Species, and Drinking Water 

Assessments for Asulam and Sodium Asulam dated December 22, 2010, 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 asulam was completed in 2002 to 

support the TRED. 

• The most recent drinking water assessment for asulam was conducted in 2002 to support 

the TRED. A new drinking water assessment based on the submission of new or upgrade 

of existing ecological fate data and current methodologies is anticipated to support 

registration review. 

• The toxicity data base for asulam is substantially complete. Endpoints for oral (i.e., 

dietary, drinking water exposure, incidental oral) exposure are adequate. Dermal, 

inhalation and endpoints for the worker exposure assessment need to be revised and 

updated consistent with the endpoints identified in the TRED assessment. 

• The Agency anticipates requiring the following data in order to support a human health 

risk assessment for asulam: 
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o GLN 870.6200 Neurotoxicity battery (acute and subchronic studies) 

o GLN 870.7800 Immunotoxicity 

• Following the submission of the toxicological data that are expected to be required, the 

Agency plans to update the human health toxicity profile as needed. 

• To support the registration review of asulam, dietary and drinking water exposure 

assessments will be updated to reflect current methodologies.

• Asulam is listed in 40 CFR §180.360 for residues in/on sugarcane and livestock 

commodities. The tolerance expressions for asulam will be reviewed during registration 

review to ensure that they appropriately covers the metabolites and degradates of asulam 

and that they specify the residues to be measured for each commodity. 

• Since there are no registered residential uses and potential residential exposures were not 

anticipated as a result of applications of asulam, a residential exposure assessment was 

not conducted for either the 1995 RED or the 2002 TRED. To support registration 

review, a residential exposure assessment that accounts for possible residential exposures 

to asulam use on non-cropland areas may be conducted. 

• To support registration review, the Agency intends to update the aggregate risk 

assessment to reflect current standards. 

• The most recent occupational exposure assessment for asulam was conducted to support 

the 1995 RED. An updated occupational risk assessment is anticipated for the 

registration review of asulam to update potential changes in the toxicity database and 

incorporate the most current methodologies. 

• Please refer to the document, Asulam: Human Health Risk Scoping Document in Support 

of Registration Review dated January 5, 2011, located in the docket for a detailed 

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

Endocrine Disruptor Screening Program:

As required by FIFRA and the Federal Food, Drug, and Cosmetic Act (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 asulam’s 

TRED 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 
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section 408(p), asulam 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. Asulam 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 asulam. 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 asulam registration 

review. 

Registration Review for Asulam – Projected Registration Review Timeline

Activities Estimated Date 

Opening the Docket 

Open Docket and Public Comment Period 2011 – March 

Close Public Comment 2011 – May 

Case Development 

Final Work Plan 2011 – August 

Issue DCI 2012 – April – June 

Data Submission 2014 – April – June 

Open Public Comment Period for Draft Risk Assessments 2015 – Oct. – Dec. 

Close Public Comment Period 2016 – Jan. – March 

Registration Review Decision 

Open Public Comment Period for Proposed Registration Review 

Decision 

 2016 – April – June 

Close Public Comment Period 2016 – July – Sept. 

Registration Review Decision and Begin Post-Decision Follow-up 2017 

Total (years) 6 
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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 asulam. 

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:

Asulam is not identified as a cause of impairment for any water bodies listed as impaired under 

section 303(d) of the Clean Water Act1

. In addition, no Total Maximum Daily Loads (TMDL) 

have been developed for asulam2. More information on impaired water bodies and TMDLs can 

be found at the Agency’s website3

. 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 Process4 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 asulam, 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 ecological and human health risk assessments, including any speciesspecific ecological effects determinations. The Agency is interested in receiving the following 

information: 

 

1 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885 2 http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant_group_name=PESTICIDES 3 http://www.epa.gov/owow/tmdl/

4 http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm
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1. suggestions from stakeholders on ways to reduce non-target organism exposures to 

asulam 

2. confirmation on the following label information: 

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 

relevant crop) 

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 crop – 

national, state, and county 

7. sub-county crop location data 

8. 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. percent crop treated – county 

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

d. total pounds per year – county 

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

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

9. state or local use restrictions 

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

and mammalian mortalities) not already reported to the Agency 

11. 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 asulam 

registration review.
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II. FACT SHEET 

Background Information:

• Asulam sodium salt PC Code: 106902; CAS#: 2302-17-2 

• Technical registrant: United Phosphorus (EPA No. 70506) 

• First registered in the U.S. in 1975. 

• Reregistration Eligibility Decision issued in 1995 and the Tolerance Reassessment 

Eligibility Decision issued in 2002. 

• There are nine FIFRA section 3 registrations and five FIFRA section 24 (c) (Special 

Local Needs) registrations. 

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

wasem.russell@epa.gov. 

• Registration Division Product Manager (PM): Kathryn Montague, 

montague.kathryn@epa.gov 

Use & Usage Information: 

For additional details, please refer to BEAD Appendix A dated April 21, 2010, and/or BEAD 

Chemical Profile for Registration Review on Asulam, Sodium Salt dated December 2, 2010, 

located in the asulam docket. 

• Asulam is a food/feed, and non-food/feed use herbicide registered for use on sugarcane, 

Christmas tree plantations, ornamentals, turf (for sod only) and non-cropland areas 

(boundary fences, fencerows, hedgerows, lumberyards, storage areas and industrial plant 

sites, and warehouse lots). 

• Asulam is also registered for use on spinach grown for seed in Washington and Oregon 

under Special Local Needs Registrations that were issued in 2008. 

• Registered asulam products are applied by foliar spray, broadcast, band treatment by 

sprayer, aircraft, low pressure ground equipment and spot treatment by spreader. 

• Asulam is only formulated as a soluble/concentrate liquid. 

• Major usage of asulam is on sugarcane, with an approximate annual usage of 700,000 

lbs./a.i. 

Recent Actions:

• There are no recent Agency actions involving asulam. 

Ecological Risk Assessment Status:

The following are key findings of the most recent ecological risk assessments for asulam. Please 

refer to the document, Registration Review: Preliminary Problem Formulation for 

Environmental Fate and Ecological Risk, Endangered Species, and Drinking Water Assessments 

for Asulam and Sodium Asulam, dated December 22, 2010, located in the docket for a detailed 

discussion of the ecological risk assessment. 
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• The most recent ecological risk assessment for asulam, conducted in support of the 1995 

RED, concluded that the use of asulam exceeded the level of concern (LOC) for 

endangered and non-endangered terrestrial and semi-aquatic plants for all uses. To 

address the identified risks of concern, the Agency specified mitigation measures in the 

RED to reduce risk and additional environmental fate and ecological effects data to 

confirm its regulatory decision. 

• Risks to terrestrial plants were previously assessed using studies conducted with technical 

asulam rather than typical end use product. Herbicidal active ingredients are usually 

formulated with adjuvants or surfactants that are intended to enhance the activity of the 

pesticide. Therefore, the sensitivity of terrestrial plants to asulam as it is typically applied 

may have been underestimated. 

Human Health Risk Assessment Status:

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

Please refer to the document, Asulam: Human Health Risk Scoping Document in Support of 

Registration Review, dated January 5, 2011, located in the docket for a detailed discussion of the 

human health risk assessment. 

Hazard Characterization: 

• Asulam is of low acute toxicity by oral, dermal and inhalation routes of exposure. It is 

not an eye or skin irritant or a dermal sensitizer. Subchronic and chronic toxicity studies 

demonstrate that the thyroid gland is a target organ for asulam. 

• Laboratory studies show no clear evidence of asulam being a developmental toxin. 

Developmental effects were seen in the rat study but only at maternally toxic doses. 

• Asulam has been classified as a possible human carcinogen. 

Dietary (Food and Drinking Water): 

• A dietary exposure analysis for food only was conducted for the 2002 TRED. An acute 

dietary risk assessment was not performed since there was no acute endpoint identified. 

A refined chronic dietary analysis was conducted that showed no risks of concern for the 

general U.S. population and all population subgroups (≤1% of cPAD). 

Residential: 

• Since there are no registered residential uses and potential residential exposures were not 

anticipated as a result of applications of asulam, a residential exposure assessment was 

not conducted for either the 1995 RED or the 2002 TRED.

Aggregate: 

• The most recent aggregate risk assessment was conducted to support the 2002 TRED. 

Short term aggregate risk from dietary/drinking water and residential exposure was 

assessed. This assessment concluded that short-term aggregate exposure to asulam via 

food, water and incidental oral exposure was less than the Agency’s level of concern. 

Occupational: 
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• A qualitative worker exposure assessment was conducted for the 1995 RED based on 

potential handler and post-application exposures to asulam. At that time, the Agency 

determined that a quantitative occupational exposure assessment was not required 

because the toxicology criteria for a quantitative assessment were not triggered and no 

endpoints of concern regarding dermal or inhalation toxicity were identified. 

Cumulative: 

• The Agency has not determined whether asulam shares a common mechanism of toxicity 

with other chemical substances. While asulam is a carbamate pesticide, it does not share 

a common mode of action with the n-methyl carbamate pesticides and therefore has not 

been included in previous n-methyl carbamate cumulative assessments. If, in the future 

the Agency determines that new information on asulam is available that could potentially 

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

revisit the need for a cumulative risk assessment. 

Incidents:

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

of asulam human incidents. No human incidents have been reported from 2002 to the 

present associated, with the use of asulam. 

• No ecological incidents involving asulam were found in the Agency’s Ecological 

Incident Information System (EIIS) database or the American Bird Conservancy’s Avian 

Incident Monitoring System (AIMS). One plant incident associated with sodium asulam 

has been reported to the Agency in an aggregated incident report from June 2003. 

Although only one incident associated with the use of asulam or sodium asulam has been 

reported to the EPA, the lack of incident reports cannot be construed as the absence of 

incidents as there can be many reasons why the Agency is not notified of adverse effects 

resulting from the use of a pesticide. Unless additional information on this 2003 

aggregated incident report becomes available, it will be assumed to be due to a registered 

use of asulam in the risk assessment. 

Data Call-In (DCI) Status:

• Several data requirements issued as part of the RED and TRED DCIs remain outstanding. 

Data submitted to satisfy these data requirements were deemed insufficient, and 

subsequent attempts to upgrade the data by new technical registrants were also deemed 

insufficient. The Agency intends to pursue these outstanding data requirements further. 

These following previously requested data requirements will need to be satisfied to 

support registration review:

o GLN 835.4100 – Aerobic soil metabolism 

o GLN 835.4300 – Aerobic aquatic metabolism 

o GLN 835.4400 – Anaerobic aquatic metabolism 

o GLN 835.6100 – Terrestrial dissipation 

o GLN 835.6100 – Frozen storage stability 
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o GLN 870.2100 – Foliar (Dislodgeable) Residue Dissipation 

Tolerances and International Harmonization: 

• 40 CFR §180.360 lists 18 tolerances for combined residues of asulam (methyl 

sulfanilylcarbamate) and its sulfanilamide containing metabolites in plant and livestock 

commodities. 

• There are currently no established Canadian, Codex, or Mexican MRLs for asulam. 

Labels:

• The labels for asulam can be obtained from the Pesticide Product Label System (PPLS) 

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