# Pro b Ec o

W a

P

repared Brian D. K Reuben B Andrew S

R eviewe d

Mark Co r 

# b lem F o

o logica l

a ter A s Re v

m

by: K iernan, Bio l B aris, Enviro n S helby, Envir o

d

by:

r bin, Branch C 

# o rmula t l Risk,

s sessm e

v iew of A

m ethyl N -[(4

- 

### CA

l ogis t

n mental Scie n

o nmental Sci

C hief

- 

# t ion fo r Endan g

e nts in

A sula m

- aminophen y 

### S Registr y PC C

n tis t entis t

Dece m

- 2 of 43- 

# r the E n g ered S Suppo r

m and S

y l)sulfonyl] c 

### y Number:

ode: 0169 0

U. O

ff En En 1 2 Ma Wa

m ber 22, 20 

# n viron m S pecies

r t of th e S odiu m

c arbamate s o 

### 2302-17- 2 0 2

S. Environ m ff

ice of Pesti c

n vironmenta l

n vironmenta l 2 00 Pennsylv a Ma il Code 750 Wa shington, D

10 

# m ental , and D

e Regi s

m Asula m

o dium salt 

### 2

m ental Prote c

c ide Progra m l Fate and E ff l Risk Branc h

a nia Ave., N W 7P D C 20460 

# Fate a D rinkin

s tratio n

m

c tion Agency

m s ff

ects Divisio n h IV W 

# nd
g

n

n-3 of 43- 1. Purpose

The purpose of this problem formulation is to pr ovide an understanding of what is known about the environmental fate and ecological effects of the registered uses of asulam (PC Code 106901) and its salt, sodium asulam (P C Code 106902). Asulam is a sele ctive post-emergent systemic carbamate herbicide. The only end-use formulation of asulam is the sodium salt of asulam. One pound of the active ingredient (ai) , sodium asulam, converts to 0.91 lbs acid equivalents (ae) asulam. Because under environmentally relevant conditions sodium asulam dissociates to the free acid, the risk assessment will be conducted on the basis of environmental exposure to asulam. This document will provide a plan for analyzing data relevant to asulam and for conducting environmental fate and ecological risk, endangered species, and drinking water assessments for its registered uses. Additionally, this problem formulation is intended to identify data gaps, uncertainties, and poten tial assumptions used to address those uncertainties relative to characterizing the ecological risk associated with the registered uses of sodium asulam.

2. Problem Formulation

2.1. Nature of Regulatory Action

Under the Federal Insecticide, F ungicide, and Rodenticide Act (FIF RA), all pesticid es distributed or sold in the United States generally must be registered by the Environmental Protection Agency (EPA). As part of determining whether a pesticide can be registered in the U.S., the Agency evaluates its safety to non-target spec ies based on a wide range of environmental and health effects studies. In 1996, FIFRA was amended by the Food Quality Protection Act, and the Agency was mandated to implement a new program for the periodic review of pesticides, i.e
., Registration Review ( http://www.epa.gov/oppsrrd1/registration_review/ ). The Registration Review program is intended to ensure that, as th e ability to assess risk evolves and as policies and practices change, all register ed pesticides continue to meet the statutory standard of no unreasonable adverse effects to human health and the environment. Changes in science, public policy, and pesticide use practic es occur over time. Through the new Registration Review program, the Agency periodically reevaluates pestic ides to make sure that as change occurs, products in the marketplace can be used safely.

As part of the implementation of the Registratio n Review program pursuant to Section 3(g) of the Federal Insecticide, Fungicide and Rodentic ide Act (FIFRA), the Agency is beginning its evaluation of sodium asulam and asulam to dete rmine whether it continues to meet the FIFRA standard for registration. This problem formulation for the envi ronmental fate, ecological risk, endangered species, and drinking water assessment chapter in support of the Registration Review will be posted in the initial docket, which will open the public phase of the review process.-4 of 43- 2.2. Previous Risk Assessments

A Registration Standard was issued in 1987, summari zing the available effects data for asulam. An ‘EFED List A Summary Report for Asulam,’ wh ich included a risk assessment, was issued in 1994. The risk assessment determined there was “a fairly high degree of certainty concerning LOC exceedances for terrestrial and semi-aqua tic plants”. Additionally, “a high level of concern” exists for aquatic plants.

A Reregistration Eligibilit y Decision (RED; USEPA 1995) was issued in 1995 which summarized the available environmental fate and effects data. The major conclusion from environmental risk assessment conducted in suppor t of the RED was that use of asulam exceeded the levels of concern (LOCs) for endangered and non-endangered terrestrial and semi-aquatic plants for all uses. The Agency required addi tional environmental fate and ecological effects data to confirm the environmental and ecologi cal risk assessment for all uses of asulam.

In the RED, several risk mitigation meas ures were required for asulam, including:

- prohibiting the aerial uses of asulam for non-cropland and Christmas trees use sites - clarifying the non-cropland use to lim it 1 gallon/A rate, 1 application/season - clarifying the Christmas tree uses to limit 1 application/season - clarifying the turf use to limit use to st ate sod farms only and 1 application/season

The Agency required a ground water label advisory and a surface water advisory for all asulam product registrations. Also, long term monitoring was deemed necessary in and near areas where asulam is used.

A drinking water assessment was conducted and sent to the Hea lth Effects Division (HED) in 2002 (D279761).

3. Stressor Source and Distribution

3.1. Mechanism of Action

“The physicochemical properties of asulam favo r high phloem mobility, which contributes to the herbicidal activity against perennial weeds. The mode of action of asulam is unique for herbicides. It is an inhibitor of folic acid bios ynthesis similar to the sulfonamide antimicrobial drugs, which are competitive inhibitors of 7,8-dihydropteroate synt hase (DHPS). The mechanism of selectivity to as ulam is reported as having gr eater metabolic degradation in tolerant species” (Pallett, 2003).

3.2. Overview of Pesticide Use and Usage

Asulam is a selective postemergent systemic car bamate herbicide used to control a variety of annual grasses and broadleaf weeds on sugar cane, spinach grown for seed, Christmas tree plantations, ornamentals, turf (St. Augustineg rass and Bermudagrass) and non-cropland uses-5 of 43- (boundary fences, fencerows, hedgerows, lumberyard s, storage areas and industrial plant sites, and warehouse lots). Its major use site is sugar cane. The only end-use formulation of asulam is soluble/concentrate liquid (sodium salt of asulam). Sodium asulam is applied by aerial or ground spray, broadcast, band, and spot treatment. Us e practice limitations prohibit applying asulam through any type of irrigation syst em; discharging into bodies of wa ter; using treated plants for feed or forage; and treating crops/s ites within 90 days of harvest.

There are currently eight Secti on 3 registered products as well as three SLN registrations for asulam ( Table 3.1 ).

TABLE 3.1. Summary of Re gistered Products Containi ng Asulam in the U.S.
Registration # Name Company Name Percent Asulam

002749-00523 Aceto Asulam 400 Herbicide Aceto Agricultural Chemicals 33.0

009779-00342 Asulam 3.3 Herbicide Winfield Solutions 33.0

034704-00904 Asulam Herbicide Loveland Products 33.0

048273-00012 Asulam Herbicide Marman USA 33.0

062719-00457 Asulam 400 Dow AgroSciences 33.0

066330-00270 Asulam Liquid Herbicide Arysta LifeScience North America 33.0

070506-00139 Asulox Herbicide United Phosphorus 33.0

070506-00141 Asulox XP United Phosphorus 31.8

OR07001600 Asulox Herbicide United Phosphorus 33.0

OR10000800 Asulam Hebicide Loveland Products 33.0

WA08000100 Asulox Herbicide United Phosphorus 33.0

There is one registered food use on sugarcane. Sugarcane represen ts the greatest total application of sodium asulam of any use. Ma ximum single application for sugarcane is 3.653 lbs ai/A allowed twice at an unspecifi ed interval for a tota l of 7.306 lbs ai/A allo wed per crop cycle. Without a specified application interval, a cons ervative assumption will be used in the risk assessment. Explicitly stating the minimum in terval would reduce uncer tainty. The sugarcane use allows ground and aerial application.

The spinach (for seed)use allows 1.3575 lbs ai/A allowed twice per crop cycle at a seven day interval, for a crop cycle total of 2.714 lbs ai/A. The spinach use is for seed crop only. The spinach use is geographically limited to Ore gon and Washington States. Information on the number of crop cycles per year for spinach in thes e areas would be useful for the risk assessment. Application to spinach is limited to ground spray.

Other non-food uses include orname ntal turf, ornamental trees, shrubs and vines, Christmas trees, forest/shelterbelt (yew and j uniper), rights of way and industria l area. All of these uses are-6 of 43- limited to ground spray applications (no aerial) and a si ngle application per crop cycle. Spot treatments are also allowed for some uses. The application rates are all generally 3.6 lbs sodium asulam per acre. A summary of currently regi stered sodium asulam uses, along with their respective methods and rates of application is presented in Table 3.2

. Table 3.2. Registered Use Patterns for Sodium Asulam

.

According to the Biological and Economic anal ysis Division’s (BEAD) Screening Level Usage Analysis (SLUA; USEPA 2010), 700,000 lbs sodium asulam are applied annually on sugarcane and 70,000 lbs sodium asulam are applied annually to sod. The SLUA also reports that less than 500 lbs are applied to sugar beets, although this is not a register ed crop. The amount applied to spinach, ornamentals, Christmas trees, fore stry or nonagricultura l areas is not known.

3.3. Environmental Fate and Transport

At this time, the following environmental fate guidelines are not fulfilled for asulam: aerobic soil metabolism (835.4100), anaerobic soil metabolis m (835.4200), aerobic aquatic metabolism study (835.4300), and terrestrial field di ssipation (835.6100). The Agency has reviewed supplemental data submitted by the registrant to upgrade th e aerobic and anaerobic so il, and aerobic aquatic metabolism studies, however the Agency still requires additional data for these guidelines. Also important for the validity of th e laboratory and field studies, an investigation of the frozen storage stability of asulam and its degradate (sulfa nilamide). These data gaps were reported in the 1995 RED, and it was stated at that time that the studies to support the soil/aquatic metabolism data requirements can be upgraded and other data requirements may have been fulfilled (e.g., storage stability data on asulam a nd its degradate). This data was never submitted therefore these data gaps still ex ist. Therefore, the lack of acce ptable field dissipation data and the concerns about the integrity of data from the laboratory studies limit the Agency's ability to assess with confidence the environmental fate of asulam. The following assessment of the environmental fate of asulam is, in part, based on uncertain data. As a result, the fate, ground and surface water assessments of asulam may cha nge after review of the additional data that remains outstanding. Use Pattern Single App. Rate (lbs ai/A) Number of App. Seasonal App. Rate (lbs ai/A) App. Interval

(days) Application Method Comments

Spinach 1.3575 2 2.714 7 Ground spray

Sugarcane 3.653 2 7.306 Not specified Aerial and ground spray Band and spot treatment allowed Ornamental turf 3.624 1 3.624 -- Ground spray

Ornamental trees/shrubs/vines 3.653 1 3.653 -- Ground spray

Nonagricultural areas and industrial areas 3.644 1 3.644 -- Ground spray Spot treatments allowed

Christmas trees 3.644 1 3.644 -- Mist blower

Forest shelterbelt (yew and juniper) 3.644 1 3.644 -- Ground spray-7 of 43- As stated previously, asulam (met hyl sulfanilylcarbamate), is an herbicide used for weed control on sugarcane, spinach, Christmas tree plantation s, ornamentals, turf, and noncropland uses. Asulam is formulated into and applied as the asulam sodium salt (sodium methyl sulfanilylcarbamate).

Asulam Asulam, Sodium Salt

Empirical Formula: C 8 H 10 N 2 O 4 S (asulam) C 8 H 9 N 2 NaO 4 S (asulam sodium salt) Molecular Weight: 230.2 (asulam) 252.2 (asulam sodium salt) CAS Registry No.: 3337-71-1 (asulam) 2302-17-2 (asulam sodium salt) PC Code: 106901 (asulam) 106902 (asulam sodium salt)

Asulam is a colorless, crystalline solid with a melting point of 143-145oC. Asulam sodium salt is a buff-colored powder with a melting point of 212- 215oC. Asulam is sol uble at approximately 0.5% in water, and moderately soluble in chlorinated hydrocarbons, petroleum oils, and hydroxylic solvents. Asulam sodium salt is sol uble at >100 g/100 mL in water at pHs 5, 6.5, and 9.

Table 3.4 summarizes the submitted environmental fate data for asulam. Additional characterization of the submitted environmental fate data is located in Appendix B

. TABLE 3.4. General Chemical Properties and En vironmental Fate Properties of Asulam, Sodium Salt.
Parameter Value Reference (MRID #) Physical/Chemical Parameters Molecular mass (g/mol) 252.2 40751501 Vapor pressure (25°C) <1 x 10 -7 mmHg 40751501 Henry’s Law Constant (25oC) 3.0 x 10 -10 Footprint Water solubility (20°C) 534,000 mg/L 40751501 Octanol-water partition coefficient (K O W ) 1.01 (Log Kow = 0.004) 40751501 Dissociation constant (pKa) (25oC) 1.29 (strong acid) Footprint-8 of 43- Parameter Value Reference (MRID #) Mobility Organic carbon partitioning coefficient (K OC, L·kg -1 ) 115 (sand) 63 (clay loam) 69 (sandy clay loam) 58 (sandy loam) 18 (artificial Speyer 2.2) 41215101

Persistence in Water Hydrolysis half-life (25°C, pH 5, 7, & 9) Stable 40997901 Aqueous photolysis half-life (25°C) 2 hours 41326001 Aerobic aquatic metabolism half-life (20oC) † 105 days (loam:water) 41767803 Anaerobic aquatic metabolism half-life (20oC) Stable 41767802
Persistence in Soil Soil photolysis half-life (25°C) 2 hours 41326002 Aerobic soil metabolism half-life (20°C) † 8 days (sand) 28 days (sandy loam) 23 days (loam) 41767801

Anaerobic soil metabolism half-life (20oC) Stable 41767802
Field Dissipation
Terrestrial field di ssipation half-life; maximum leaching depth No acceptable data --

Aquatic Bioconcentration Bioconcentration Factor ( BCF) in fish Low Kow

† Denotes uncertain data

Based on available data, the major routes of di ssipation are leaching into ground water and biotic degradation under aerobic conditions . Asulam residues are considered mobile to highly mobile based on FAO Soil Mobility Classifications (USEPA, 2006). Due to its solubility in water, rain occurring immediately following application may in crease the amount of ch emical getting into ground water. Given the compound’s low Koc, sediment-bound runoff is not expected. Therefore, surface runoff could be another majo r route of dissipation. Based on the laboratory studies, photolysis in water and on soil appear to be major routes of degradation for asulam (halflife of 2 hours in water, and in soil; MRID 41326001, 41326002). However, the role of photolysis may be less significant u nder natural field conditions than in the laboratory due to the clarity of the water body and depth of the photolytic zone, as well as light intensity. This was demonstrated by the detection of low levels of asulam residues (0.1 ppb) in a surface water study (MRID 42704901). Based on acceptable data, the Agency concludes that asulam is very soluble in water, with a water solubility of 4,000 ppm, s odium salt of asulam is considered very highly soluble (>900,000 ppm). Asulam is stable to hydrolysis at pH's of 5, 7, and 9 (MRID 40997901). Although this chemical photodegrades ve ry rapidly in aqueous solution at pH 9, with a half-life of 2 hours, no degradation products were present at levels greater than 10 percent of the applied (MRID 41326001).

On sandy loam soil, asulam was found to be re adily photodegradable with a half-life of 1.5 hours (MRID 41326002). Sulfanilamide, the major degradat ion product formed on soil, was present at 27.4 percent of the applied two hours after e xposure to light (MRI D 41326002). Based on the-9 of 43- low vapor pressure of asulam (< 1 x 10 -7 ), volatilization from soils will not be an important dissipation route (MRID 40751501). The low octanol/w ater partition coefficient suggests that asulam will have a low tendency to accumulate in fish (Kow of 1.01; MRID 40751501). Based on supplemental data, asulam is much less pers istent under aerobic than anaerobic soil and aquatic conditions (half-life of 8-28 days in soil, 105 days in water; MRID 41767802, 41767803). Under anaerobic conditions, biotic metabo lism is reduced and le aching potential is enhanced (half-life was greater than one year; MRID 41767802). Sulfanilamide was the major degradate detected in the aerobic/anaerobic so il, and aerobic/anaerobic aquatic metabolism studies. Acetyl asulam (14.3% of the applied at 7 days) was only found in the soil incubated under anaerobic soil/aqu atic environment.

Asulam is expected to be very mobile due to its low soil adsorption coefficients (K ads ranges 0.6- 1.0, K oc ranges 18-115; MRID 41215101). Results from the column leaching studies for unaged and aged asulam residues showed that the pa rent compound has a high potential for leaching (MRID 40965001). Although no mobility studie s were conducted for the degradate (sulfanilamide), based on the aged leaching study for asulam, sulfanilamide showed low mobility compared to the parent.

Asulam has the physical/chemical characteristic s in common with those pesticides that are known to leach to ground water or run off to surface water. Small amounts of asulam and sulfanilamide were detected in the leached soil columns. However, the dissipation of asulam in the field cannot be confirmed at this time becau se the registrant has not submitted any acceptable field dissipation data. Furthe r, the field dissipation/sma ll-scale prospective ground-water monitoring study provided little conclusive informa tion due to the problems of residue analysis in the soil; however, it is adequa te to allow the Agency to concl ude that asulam is highly mobile and will likely reach ground water especially under the shallow ground-water conditions (MRID 42534501).

Results from an asulam drinking water survey of surface water indicate the presence of low levels of asulam (0.1 ppb) at the intakes to community water systems (MRID 42704901). This demonstrates the ability of the compound to move offsite into surface water.

The lack of acceptable field dissipation data and th e concerns about the inte grity of data from the laboratory studies limit the Agency's ability to assess with confidence the environmental fate of asulam. The above assessment of the environmen tal fate of asulam was, in part, based on uncertain data. As a result, the fate, ground and surface water assessments of asulam may change after review of the a dditional data being required.

3.3.5. Bioaccumulation

There are no data on the biocon centration potential of asulam in fish. The octanol-water partition coefficient is sufficien tly low, a value of 1.01 at 25 o C (log K OW = 0.004; MRID 40851501), that bioaccumulation in organisms is not expected. The EpiSuite estimate for the bioconcentration f actor was 3.2 L·kg -1 wet-weight. This suggests that bioconcentration and bioaccumulation are not a concern.-10 of 43- 4. Receptors

Consistent with the process described in th e Overview Document (USEPA 2004), the risk assessment for asulam and sodium asulam relies on a surrogate species approach. Toxicological data generated from surrogate test species, wh ich are intended to be representative of broad taxonomic groups, are used to extrapolate the poten tial effects on a variety of species (receptors) included under these ta xonomic groupings.

Acute and chronic toxicity da ta from studies submitted by pesticide registrant, along with the available open literature, will be used to eval uate the potential direct and indirect effects of asulam to aquatic and terrestria l receptors. This includes toxi city on the technical grade active ingredient, degradates, and when available, formulated products ( e.g. , “Six-Pack” studies). Open literature studies were id entified through EPA’s publica lly available ECOTOXicology (ECOTOX) database (November 2010), which empl oys a literature search engine for locating chemical toxicity data for aquatic and terrestr ial plants and wildlife. The evaluation of both sources of data may also provide insight into th e direct and indirect e ffects of asulam usage on biotic communities from loss of species that are sensitive to the chemical and from changes in structure and functional characteristics of the affected communities.

A brief summary of the aquatic and terrestrial toxicity data available for the species most sensitive to asulam is provided in Sections 4.1 and 4.2, respectively. Most terrestrial and aquatic effects data were derived using asulam and are expressed in term s of acid equivalents (ae). A more complete summary of the available data is presented in Appendix B . In addition, a summary of ecological incidents associated w ith asulam and a description of ecosystems potentially at risk are provided in Sections 4.3 and 4.4, respectively. As noted previously, the sulfanilamide degradate forms to varying degr ees under different environmental conditions. Toxicity data on the sulfanilamide degradate woul d reduce uncertainty in the risk assessment due to its variable formation and exposur e to environmental receptors.

Toxicity to fish and aquatic invertebrates is categorized using the system shown in Table 4.1 (US EPA, 2004). Toxicity to terrestrial fauna (birds and ma mmals) is categorized using the system shown in Table 4.2 . Toxicity categories for plants have not been defined.

Table 4.1. Categories of Acute Toxicity for Aquatic Animals
LC 50 (ppm) Toxicity Category < 0.1 Very highly toxic > 0.1 - 1 Highly toxic > 1 - 10 Moderately toxic > 10 - 100 Slightly toxic

> 100 Practically nontoxic

Table 4.2. Categories of Acute Toxicity for Terrestrial Animals
LD 50 (mg/kg) LC 50 (ppm) Toxicity Category <10 <50 Very highly toxic 10-50 50-500 Highly toxic-11 of 43- 51-500 501 - 1000 Moderately toxic 501-2000 1001 - 5000 Slightly toxic

>2000 >5000 Practically nontoxic

4.1. Effects to Aquatic Organisms

The most sensitive aquatic toxicity data from registrant-submitted studies are provided in Table 4.3 . There are several studies available in ECOTOX which will be reviewed for the risk assessment. Based on the available information, asul am is classified as to practically nontoxic to fish and slightly toxic aquatic invertebrates on an acute exposure basis. Both vascular and nonvascular aquatic plants ar e affected by asulam.

Table 4.3. Aquatic Toxicity Profile for Asulam
Taxonomic Group Species (Common Name) Endpoint (mg ae/L) Acute Classification Reference (MRID)

Freshwater Fish Oncorhyncus mykiss (Rainbow Trout) LC 50 >175 Practically nontoxic 40872001

Freshwater Invertebrates Daphnia magna (Waterflea ) EC 50 =27.1 Slightly toxic 00098507

Estuarine/marine Fish -- -- -- -- a

Estuarine/marine Invertebrates Palaemonetes pugio (grass shrimp) LC 50 >100 Practically nontoxic 00098508

Vascular plants Lemna gibba (duckweed) EC 50 =0.14 NOAEC=0.07 -- b 42611701

Nonvascular plants Pseudokirchneriella subcapitata EC 50 =0.18 NOAEC=0.02 -- 42560301

a No data available
b Toxicity categories for plants have not been defined.

4.2. Effects to T errestrial Organisms

Table 4.3 summarizes the most sensitive terrestrial toxicity endpoints for asulam, based on an evaluation of the submitted data. Open literatu re studies have been identified through ECOTOX and will be reviewed for the risk assessment. As ulam is classified as practically nontoxic to terrestrial birds on an acute oral and subacute di etary exposure basis; asulam is classified as practically nontoxic to mammals on an acute oral exposure basis. No avian reproduction data has been submitted. Asulam is classified as practically nontoxic to young adult honey bees ( Apis mellifera ) on an acute contact exposure basis.

As expected with an herbicide, asulam has adverse effects on plants. The studies were conducted with technical sodium asulam rather than typical end use product (TEP) as required under 40 CFR Part 158. Herbicidal active ingredient s are usually formulated with adjuvants or surfactants that enhance the activity of the pesticide. Therefore, the sensitivity of terrestrial plants to formulated sodium asulam may be underestimated.

Table 4.3 Terrestrial Toxici ty Profile for Asulam-12 of 43- Taxonomic Group Surrogate Species (Common Name) Endpoint Acute Classification/ Chronic effect Reference (MRID)

Birds Perdix perdix (Partridge) LD 50 =3674.5 mg ae/kg bw Practically nontoxic 00056417

Anas platyrhynchos (Mallard duck) LC 50 >75,000 mg ae/kg diet Practically nontoxic 00056418

Mammals Rattus norvegicus (Laboratory rat) LD 50 >5000 mg ae/kg bw Practically non toxic 42110001

Laboratory rat LOAEL=5000 mg ae/kg-diet NOAEC=1000 mg ae/kg-diet Reduced number of live births per litter 00098540

Terrestrial Invertebrates Apis mellifera (Honey bee) LD 50 >36.26
μ g/bee Practically nontoxic 00018842

Seedling
emergence Lactuca sativa (Lettuce) EC 25 =0.084 lbs ai/A NOAEC a =0.026 lbs ai/A -- b 42613801

Vegetative vigor Lactuca sativa (Lettuce) EC 25 =0.085 lbs ai/A NOAEC=0.044 lbs ai/A -- 42613801

a EC 05 used in lieu of a NOAEC

b Toxicity categories for plants have not been defined

. Although avian subacute and mamm alian acute endpoints are nondefi nitive values, preliminary calculation of RQs (not shown) indi cate that the highest dose tested ( e.g. 5000 mg ae/kg-bw) are sufficiently higher than the EECs that furt her data are not needed at this time.

4.3. Incident Database Review

A review of the Ecological Incident Informati on System (EIIS) database for incidents involving asulam and sodium asulam was conducted on N ovember 3, 2010. No incidents are reported in the database. Similarly, a search of the Avian Incident Monitoring System (AIMS; http://www.abcbirds.org/abcprograms/ policy/pesticides/aims/aims/index.cfm ), a database administered by the American Bird Conservanc y which contains publicly available data on reported avian incidents involving pesticides did not report any in cidents for asulam or sodium asulam as of November 3, 2010. Pesticide regist rants report certain types of incidents to the Agency as aggregate counts of incidents occurri ng per product per quarter. One aggregate plant incident has been reported to the Agency asso ciated with sodium asulam in an aggregated incident report from June, 2003. Although only one incident associated w ith the use of asulam or sodium asulam has been reported to the EPA, the lack of incident re ports cannot be construed as the absence of incidents as there can be ma ny reasons why the Agency is not notified of-13 of 43- adverse effects resulting from th e 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.

4.4. Ecosystems Potentially at Risk

The ecosystems at risk are often extensive in scop e; therefore, it may not be possible to identify specific ecosystems during the development of a nation-wide ecological risk assessment. However, in general terms, terrestrial ecosystem s potentially at risk could include the treated field and immediately adjacent areas that may recei ve drift or runoff. Areas adjacent to the treated field could include cultiv ated fields, fencerows and hedgero ws, meadows, fallow fields or grasslands, woodlands, riparian habita ts and other uncultivated areas.

Aquatic ecosystems potentially at risk include wa ter bodies adjacent to, or downstream from, the treated field and could include impounded bodies such as ponds, lake s and reservoirs, or flowing waterways such as streams or rivers. For uses in coastal areas, aquati c habitat also includes marine ecosystems, including estuaries.

5. Assessment Endpoints

Assessment endpoints are defined as “explicit expressions of the ac tual environmental value that is to be protected.” 1 Selection of the assessment endpoi nts is based on valued entities ( e.g., fish, birds), the ecosystems potentially at risk ( e.g., waterbodies, riparian vegetation, and upland habitats), the migration pathways of asulam ( e.g., runoff, drift, etc .), and the routes by which ecological receptors are exposed to asulam ( e.g., direct contact, etc. )

. Assessment endpoints for asulam include direct toxic effects on the surv ival, reproduction, and growth of the receptors, as well as indirect e ffects, such as reduction of the prey base or modification of habitat. Each assessment endpoint requires one or more “measures of ecological effect,” defined as changes in the attributes of an assessment endpoint or changes in a surrogate entity or attribute in response to exposure to a pesticide. Specif ic measures of ecological effect are generally evaluated based on acute and chronic toxicity information from registrantsubmitted guideline tests that are performed on a limited number of organisms. Additional ecological effects data from the open literature will also be considered.

1 From U.S. EPA (1992). Framework for Ecological Risk Assessment. EPA/630/R-92/001.-14 of 43- 6. Conceptual Model

For a pesticide to pose an ecological risk, it mu st reach ecological receptors in biologically significant concentrations. An exposure pathway is the means by which a pesticide moves in the environment from a source to an ecological recepto r. For an ecological pathway to be complete, it must have a source, a release mechanism, an environmental transport medium, a point of exposure for ecological receptors, an d a feasible route of exposure.

The conceptual model for asulam provides a writ ten description (risk hyp othesis) and visual representation (conceptual diagra m) of the predicted relationships between asulam, potential routes of exposure, and the pr edicted effects for the assessmen t endpoint. A conceptual model consists of two major components: risk hypot hesis and a conceptual diagram (USEPA 1998b).

Based on the available data (including those from uncertain studies), asulam (sodium asulam) is highly to very highly soluble, stable in water without light, unstable in water and on soil under light; however, small amounts of as ulam were detected in surface water. Asualm is relatively unstable in soil under aerobic conditions, but very stable in soil and sediment under anaerobic conditions. It is very mobile in soil, asulam is not volatile, and will not likely accumulate in aquatic food webs. With these properties, it appear s that asulam is highly mobile and has a strong potential to leach into ground water or move offsite into surface water. The Agency has concluded from the small-scale prospective ground-water studies that asulam will likely reach ground water especially under the shallow ground- water conditions. Given its relatively low K ow , asulam is not expected to bioaccumulat e in aquatic or terrestrial food chains.

6.1. Risk Hypothesis

A risk hypothesis describes the predicted re lationship among the stre ssor, exposure, and assessment endpoint response along with the rati onale for their selection. For asulam, the following ecological risk hypothesi s will being employed for the na tional-level ecological risk
assessment:

Given the uses of asulam and its environmental fa te properties, there is a likelihood of exposure to non-target terrestrial and aqua tic organisms. When used in accordance with the label, asulam may result in potential adverse effects upon the surviv al, growth, and reproduction of non-target terrestrial and aquatic organisms.

6.2. Conceptual Diagram

The conceptual model used to depict the potentia l ecological risk associated with the use of asulam (the stressor) assumes that as a pesticid e, asulam can adversely affect terrestrial and aquatic organisms (the receptors) if environmental concentrations exceed toxic thresholds as a result of application accordi ng to the label directions ( Figure 1 ). Ecological receptors that may potentially be exposed to asulam include terrestrial and semi-aquatic wildlife ( e.g. , mammals, birds, terrestrial-phase amphibians and reptile s), terrestrial and se mi-aquatic plants, and-15 of 43- terrestrial invertebrates ( e.g. , honey bees) ( Figure 2) . Additionally, given the mobility of asulam, aquatic organisms ( i.e. , freshwater and estuarine/marine fish and invertebrates, aquaticphase amphibians, and aquatic plants) are pote ntial receptors in adja cent water bodies through off-site transport of asulam from the application site thr ough runoff, erosion, spray drift.

Figure 1. Conceptual model for asulam exposure to aquatic organisms. Dashed lines indicate route of exposure considered of lower importance for asulam. 

### Stressor

Source

Receptors

Attribute Change Sodium Asulam (and degradates)

Spray drift

Fish/aquatic-phase amphibians Eggs Larvae Juveniles / Adults

Individual organisms Reduced survival Reduced growth Reduced reproduction Food chain Reduction in algae Reduction in prey Habitat integrity Reduction in primary productivity Reduced cover Community change Surface water/ Runoff

Aquatic Animals Invertebrates Vertebrates 

### Exposure Media

Uptake/gills or integument

Ingestion Ingestion Atmospheric transport

Wet/dry deposition Soil Ground water

Uptake/gills or integument

Aquatic Plants N on-vascular Vascular Uptake/cell, roots, leaves Riparian plant terrestrial
exposure pathways see

Figure 2-16 of 43- Figure 2. Conceptual model for asulam exposure to terrestrial organisms. Dashed lines indicate route of exposure considered of lower importance for asulam.

7. Analysis Plan

In order to address the risk hypot hesis, the potential for adverse effects on the environment will be estimated. The use, environmental fate, and ecological effects of asulam will be characterized and integrated to assess the risks. This will be accomplished using a risk quotient (ratio of exposure concentration to effects concentration) approach. Although risk is often defined as the likelihood and magnitude of adverse ecological e ffects, the risk quotient-based approach does not provide a quantitative estima te of likelihood and/or magnitude of an adverse effect. However, as outlined in the Overview Docume nt (USEPA 2004), the likelihood of effects to individual organisms from par ticular uses of asulam may be estimated using the probit doseresponse slope and either the level of concern (d iscussed below) or the actual calculated risk quotient value.

This analysis plan will be revisited and may be revise d depending upon the information submitted by the public in response to the opening of the Registration Review docket for asulam. 

### Stressor

Source

Rece p tors

Attribut

e Sodium Asulam (and degradates)

Direct

a pp lication S p ra y drif t

Birds / Terrestrialphase amphibians / reptiles / mammals/ Insects Terrestrial

insects

Individual organisms Reduced survival Reduced growth Reduced reproduction Food chain Reduction in Habitat integrity Reduction in primary
p roductivity Reduced cover Terrestrial/riparian plants grasses/forbs, fruit, seeds (trees, shrubs) Runoff

Mammals 

### Exposure Media Soil

In g estion In g estion

In g estion In g estion Dermal u p take/In g estion Atmospheric transport

Root u p take Wet/dr y

Birds / Amphibians

In g estio-17 of 43- 7.1. Stressors of Concern

The stressor of concern in the assessment will be asulam. As previously discussed, technical sodium asulam is expected to dissociate to asulam acid when mixed with water for spray applications and remain in the acid form unde r environmentally relevant conditions alone.

There are no known applications of specific mixtur es of asulam with other chemicals. In its ecological risk assessments, the Agency does not r outinely include an eval uation of mixtures of active ingredients, either those mixtures of multip le active ingredients in product formulations or those in the applicator’s tank. In the case of the product formulat ions of active ingredients (that is, a registered product containing more than on e active ingredient), each active ingredient is subject to an individual risk assessment for regulatory decision regarding the active ingredient on a particular use site. If effect s data are available for a formulat ed product containing more than one active ingredient, the data may be used qual itatively or quantitatively in accordance with the Agency’s Overview Document and the Serv ices’ Evaluation Memorandum (USEPA, 2004; Williams and Hogarth, 2004).

7.2. Measures of Exposure

In order to estimate risks of asulam exposures in aquatic and terrestrial environments, exposure modeling will be based on maximum app lication rates and methods cited in Table 3.2. Measures of exposure are based on aquatic and terrestria l models that predict estimated environmental concentrations (EECs) of asulam. The models used to predict aquatic EECs are the Pesticide Root Zone Model coupled with the Exposure Analysis Modeling Syst em (PRZM/EXAMS). The model used to predict terrestr ial EECs on food items is the Terrestrial Residue Exposure model (T-REX). The model used to derive EECs relevant to terrestrial and wetland plants is TerrPlant. These models are parameterized using relevant revi ewed environmental fate data from registrant submissions and the literature. Model input values will be consistent with the most recent version of the input parameter guidance (Version 2.1; USEPA 2009).

PRZM (v3.12.2; 5/15/05) and EXAMS (v2.98.04.06; 4/ 25/05) are simulation models coupled with the linkage program shell: PE5 (P RZM E XAMS Model Shell; v5 .0; 11/15/06), which incorporates the standard scenarios developed by EFED. The models ge nerate daily exposures and calculated 1-in-10 year EECs of asulam and possibly (depending on the outcome of environmental fate studies) toxicologica lly significant degradatation products (e.g., sulfanilamide). PRZM simulates pesticide fate and transport as a result of leaching, direct spray drift, runoff and erosion from an agricultural field, and EXAMS estimates environmental fate and transport of pesticides in a surface water bod y for a 30-year period. The combined model is designed to estimate pesticide concentrations fou nd in water (standard pond) at the edge of the treated field. As such, it provide s high-end values of the pesticid e concentrations that might be found in ecologically sensitive environments follo wing pesticide application. The location of the field is specific to the crop being simulated usi ng site-specific information on the soils, weather, cropping, and management factors as sociated with the scenario. The crop/location scenario is intended to represent a high-e nd exposure site on which the crop is normally grown. Based on historical rainfall patterns, the receiving water body receives multiple runoff events during the-18 of 43- years simulated. Weather and agricultural practices are simulated for 30 years so that the 10-year exceedance probability at the site can be estimate d. The simulation is generated using 30 years of meteorological data, encompassing the years from 1961 to 1990. Additional information on these models can be found at: http://www.epa.gov/oppefed1/models/water/index.htm

. The standard scenarios used for ecological pest icide assessments assume application to a 10- hectare agricultural field that drains into an ad jacent 1-hectare water body that is 2 meters deep (20,000 m 3 volume) with no outlet. PRZM/EXAMS is used to estimate screening-level exposure of aquatic organisms to asulam. The measure of exposure for aquatic species is the 1-in-10 year return peak or rolling mean c oncentration. The 1-in-10 year p eak is used for estimating acute exposures of direct effects to aquatic organism s. The 1-in-10-year 60-day mean is used for assessing chronic exposure to fish and aquatic-ph ase amphibians. The 1-in-10-year 21-day mean is used for assessing chronic expos ure to aquatic invertebrates.

Exposure estimates for terrestrial organisms assu med to be in the target area or in an area exposed to off-site deposition are derived us ing the T-REX model (version 1.4.1, 10/09/2008). This model incorporates the Kenaga nomograph, as modified by Fletcher et al. (1994), which is based on a large set of field residue data. The upper limit values from the nomograph represent the upper bound of residue values from actual fiel d measurements (Hoerger and Kenaga 1972). The Fletcher et al. (1994) modifications to the Kenaga nomograph are based on measured field residues from 249 published research papers, incl uding information on 118 species of plants, 121 pesticides, and 17 chemical classes. Base d on these data, T-REX assumes a 35-day foliar dissipation half-life in th e absence of other data.

The S creening I mbibition P rogram (SIP v.1.0, Released June 15, 2010) was used to calculate an upper bound estimate of exposure using asulam’s solubility (534,000 ppm), the most sensitive acute and chronicavian t oxicity endpoints (LD 50 =3674.5 mg ai/kg-bw; NOAEL not available) and the most sensitive acute and chronic ma mmalian toxicity endpoints (enter mammalian species with LD 50 =5000 mg ai/kg-bw and NOAEL=1000 mg ai/kg-diet). Drinking water exposure alone was determined to be a potenti al pathway of concern for avian and mammalian species on an acute and chronic basis (avian chronic assumed due to lack of data).

This pathway will be explored further with th e development of SIP v.2.0 in the risk assessment for asulam. Detailed information about the SI P v.1.0, as well as the tool, can be found on the EPA’s website at http://www.epa.gov/pesticides/s cience/models_pg.htm#terrestrial

. EECs for terrestrial plants are derived usi ng TerrPlant (version 1.2.2, 12/26/2006). This model uses estimates of pesticides in runoff and in spray drift to calculate EECs. EECs are based upon solubility, application rate and minimum incorporation depth.

The AgDRIFT (v2.01; May 2001) or AgDisp (versi on 8.15) spray drift mode l may be used to assess exposures of organisms to asulam depos ited on terrestrial habitats by spray drift.-19 of 43- 7.3. Measures of Effect

Ecological effects data are used as measures of di rect and indirect effects to biological receptors. Effects data are obtained from registrant-submitted studies or from literature studies identified by the ECOTOX database.

The acute measures of effect used fo r animals in this assessment are the LD 50 , LC 50 and EC 50
. LD stands for "Lethal Dose", and LD 50 is the amount of a material, given all at once, that is estimated to cause the death of 50% of the test organisms. LC st ands for “Lethal Concentration” and LC 50 is the concentration of a chemical that is estimated to kill 50% of the test organisms. EC stands for “Effective Concentration” and the EC 50 is the concentration of a chemical that is estimated to produce a specific effect in 50% of the test organisms. Endpoints for chronic measures of exposure for listed and non-lis ted animals are the NOAEL/NOAEC and NOEC. NOAEL stands for “No Observed-Adverse-Effect-Level ” and refers to the hi ghest tested dose of a substance that has been reported to have no harm ful (adverse) effects on test organisms. The NOAEC ( i.e. , “No-Observed-Adverse-Effect-Concentration” ) is the highest test concentration at which none of the observed effects were statistically different fr om the control. For non-listed plants, only acute e xposures are assessed ( i.e. , EC 25 for terrestrial plants and EC 50 for aquatic plants); for listed plants either the NOAEC or EC 05 is used.

Where available, sublethal effects observed in both registrant-submitted and open literature studies will be evaluated qualitatively. Such effects may include behavioral changes ( e.g. , lethargy and changes in colora tion). Quantitative assessments of risks, though, are limited to those endpoints that can be di rectly linked to the Agency’s assessment endpoints of impaired survival, growth and reproduction.

In the absence of taxon-specific da ta, the assessment of risk fo r direct effects to non-target organisms makes the assumption that toxicity of as ulam to birds is similar to terrestrial-phase amphibians and reptiles. The same assumption is made for fish and aquatic-phase amphibians. In the absence of data for either acute or chroni c effects, the conservative assumption will be to presume that asulam is toxic.

7.4. Integration of Exposure and Effects

Risk characterization is the integration of e xposure and ecological effects characterization to determine the potential ecological risk from the registered uses of asul am and the likelihood of direct and indirect effects to non-target organisms in aquatic and terrestrial habitats. The exposure and toxicity effects data are integrated in order to evaluate the risks of adverse ecological effects on non-target spec ies. For the assessment of as ulam risks, the risk quotient (RQ) method is used to compare exposure and m easured toxicity values. EECs are divided by acute and chronic toxicity values . The resulting RQs are then compared to the Agency’s Levels of Concern (LOCs) (USEPA 2004). These criteria are used to indicate when asulam use, as directed on the labels, has the potential to cause a dverse direct or indirect effects to non-target organisms. In addition, incident data from the EIIS will be considered as part of the risk characterization.-20 of 43- 7.5. Deterministic and Probab ilistic Assessment Methods

The quantitative assessment of risk will primarily depend on the deterministic point-estimate (RQ) based approach described in the risk asse ssment. An effort will be made to further qualitatively describe risk using probabilistic to ols that the Agency has developed. These tools have been reviewed by FIFRA Scientific Advisory Panels ( http://www.epa.gov/sc ipoly/sap/index.htm ) and have been deemed as appropriate means of refining assessments where deterministic approaches have identified risks. Newer tools may be available to assess the routes of exposure ( e.g. TIM and SWAMP models) and will be applied as appropriate in Re gistration Review.

7.6.. Endocrine Disruptor Screening Program

As required under FFDCA section 408(p), EP A has developed the Endocrine Disruptor Screening Program (EDSP) to determine whether certain substances (inc luding pesticide active and other ingredients) may have an effect in humans or wildlife si milar 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 ap proach 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 estrog en, androgen, or thyroid (E, A, or T) hormonal systems. Chemicals that go th rough Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stag e of the EDSP where EPA will determine which, if any, of th e Tier 2 tests are necessary base d on the available data. Tier 2 testing is designed to identify a ny adverse endocrine related eff ects caused by the substance, and establish a dose-response 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 pesticid e active ingredients and 9 inert ingredients. This list of chemicals was selected based on th e potential for human exposure through pathways such as food and water, residen tial activity, and certain post-applic ation agricultural scenarios. This list should not be construed as a lis t of known or likely e ndocrine disruptors.

Asulam 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 Agen cy must screen all pesticide chemicals. Accordingly, EPA anticipates issuing future EDSP test orders/data call-ins for all pesticide active ingredients.

For further information on the status of the ED SP, the policies and pro cedures, the list of 67 chemicals, the test guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/

.

7.7. Endangered Species Assessment

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency will evaluate risks to Federally-listed th reatened and/or endangere d (listed) species from-21 of 43- registered uses of sodium asulam. This asse ssment will be conducted in accordance with the Overview Document (USEPA 2004), provisi ons of the ESA, and the Services’ Endangered Species Consultation Handbook (USFWS/NMFS, 1998).

The assessment of effects associat ed with the registration of asul am is based on an action area. The action area is considered to be the area directly or indirectly affected by the federal action, as indicated by the exceedance of Agency Levels of Concern (LOCs) used to evaluate direct or indirect effects. The Agency’s approach to defining the action area under the provisions of the Overview Document (USEPA 2004) considers the results of the risk assessment process to establish boundaries for that action area with the understandi ng that exposures below the Agency’s defined LOCs constitute a no-effect threshold. For th e purposes of this assessment, attention will be focused on the footprint of the action ( i.e ., the area where asulam application occurs), plus all areas where offsite transport ( i.e ., spray drift, runoff, etc .) may result in potential exposure that exceeds the Agency’s LOCs. Specific measures of ecological effect that define the action area for listed species include any direct and indi rect effects and/or potential modification of its critical habitat, including reduction in survival, growth, and reproduction as well as the full suite of sublethal effects availabl e in the effects literature. Ther efore, the action area extends to a point where environmental exposures are below any measured lethal or sublethal effect threshold for any biological entity at the whole organism, organ, tissue, and cellular level of organization. In situations where it is not possible to determin e the threshold for an observed effect, the action area will initially be assumed to include all counties where asulam is used in the United States.

7.8. Drinking Water Assessment

In order to bring the drinking water exposure assessment up to da te with current data, models and simulation model guidance, a new drinking water assessment will be conducted to support future human health dietary risk assessmen ts of asulam. The drinking water exposure assessment will be conducted for the maximum labeled use in support of the human health dietary risk assessment. The drinking water assessment will incorporate model estimates of asulam alone in surface water and ground water incl uding any residues that are determined to be of toxicological concern. Concen trations of asulam in surface waters will be estimated using PRZM/EXAMS (see description above) but using th e Index Reservoir scenario rather than the standard pond used with a quatic exposure assessment.

An Estimated Drinking Water Concentration (E DWC) of asulam in ground water will be estimated using EFED’s Tier I aquatic mode l SCIGROW (Screening Concentration in Ground Water, version 2.3; 8/8/2003). SCIGROW is a re gression model used as a screening tool to estimate pesticide concentrations found in ground water used as drinking water. The output of SCIGROW represents the concentrations that might be expected in shallow unconfined aquifers under sandy soils, which is repres entative of the ground water most vulnerable to pesticide contamination likely to serve as a drinking wate r source. If significant amounts of asulam are found to deposit in the environment due to releas es from the potato storage facility use, a drinking water assessment will be performed for this use using PRZM/EXAMS and SCIGROW. In this case, the deposited residues will be treated as if they were a soil application of a pesticide in PRZM.-22 of 43- The drinking water assessment will also include available surface and groundwater monitoring data with consideration of change s in use patterns that may have occurred. States are encouraged to submit monitoring data for review.

8.0. Preliminary Identification of Data Gaps

8.1. Environmental Fate

The studies submitted to fulfill environmental fate data requirements for asulam/sodium asulam are not sufficient to conduct an exposure assess ment; five requirements have not been met as stipulated by 40 CFR part 158 Subpart N §158.1300 fo r all pesticides with use patterns for terrestrial food and nonfood applicat ions: 1) There is only on e supplemental aerobic aquatic metabolism study, and additional data on the sample processing times is needed to upgrade this study. This study is necessary in order to describe the fate of asulam in surface water bodies down-gradient from terrestrial use sites. 2) There is only one supplemental aerobic soil metabolism study conducted three soils. Additional data on the sample processing times is needed to upgrade this study. The gui deline stipulates that results from at least four relevant soils of different organic carbon content, pH, clay co ntent, and microbial biomass must be submitted in order to characterize the vari ability in aerobic biode gradation of asulam in the environment (currently the Agency has three). 3) Submissi on of an acceptable anaerobic aquatic metabolism study using an additional sedimen t: water system is necessary to understand the degradation of asulam in oxygen-limiting environments. 4) An acceptable terrestrial fi eld dissipation study is required for all pesticides with use patterns fo r terrestrial food and nonfood applications. 5) Submission of a storage stability st udy is essential in order to be confident that any degradation measured in the test system was due solely to th e environment of that test system, and not due to handling and storage. Lastly, although not necessary for exposure assessment, submission of an environmental chemistry method in water, soil, a nd sediment as well as associated independent laboratory validations for these methods is also necessary in order to support enforcement and monitoring purposes at the federa l, state, and local levels.

Data Call-In tables for the anticipated data needs are provided in APPENDIX A

. Table 8.1 identifies studies by MRID that offer data fo r each guideline requirement, as well as study classifications and whether or not further data are needed in order to support risk assessment ( i.e. , whether there is a data gap).

Table 8.1. Summary of available environmental fate data.

Guideline Study Title MRID Classification Data Gap? Comments

835.2120 Hydrolysis 40997901 Acceptable

No N o significant issues affec ting the acceptability of
t he study were noted.

00098513 Unacceptable M aterial balance for the first sample was incomplete h aving not accounted for up to 20% of the test

m aterial.

835.2240 Photodegradation in Water 41326001 Acceptable No N o significant issues affec ting the acceptability of
t he study were noted.-23 of 43- Guideline Study Title MRID Classification Data Gap? Comments

00047845 Unacceptable Sampling protocol was inadeq uate (too few samples,

n o dark controls, incubation temp was not reported). A nalytical methods were incomplete. No immediate
p osttreatment samples and the test solutions were

u ncharacterized. Degradates were not addressed. A rtificial light was incompletely characterized and

n ot compared to natural sunlight. Conclusions were

n ot supported by data.

00098514 Unacceptable M aterial balances were incomplete. Degradates were

n ot identified, and artificial light source was not

a dequately compared to natural sunlight.

835.2410 Photodegradation on Soil 41326002 Acceptable

No N o significant issues affec ting the acceptability of
t he study were noted.

00098515 Unacceptable N o samples were taken immediately posttreatment. A rtificial light source was not reported (and i ntensity), and was not compared to natural sunlight. Soils were not classified according to the USDA
t extural classification system.

835.4100 Aerobic Soil Metabolism 00098516 Unacceptable

Yes T he soil was not classified according to the USDA Soil Textural Classification System, and the i ncubation temperature was no t constant. Degradates

w ere not accurately characterized.

00084802 Unacceptable T he sampling protocol was inadequate to assess the d ecline of asulam in soil and the material balance

w as incomplete. The purity of the test substance was

n ot specified. The soil was not classified according to
t he USDA Soil Textural Cl assification System, and
t he CEC of the soil was not reported.

41767801 Supplemental / Upgradable P revious studies indicated that freezing storage can

a ffect residue characterization. Additional data is

n eeded to support the registrant’s claim that sample
p rocessing occurred immediately following sampling.

835.4200 Anaerobic Soil Metabolism 00098517 Unacceptable

Yes Soil samples were incubated aerobically for longer
t han one half-life prior to establishing anaerobic

c onditions. Degradates were not accurately

c haracterized. The soil was not classified according
t o the USDA Soil Textural Classification System,

a nd incubation temperature was not held constant.

41767802 Supplemental / Upgradable P revious studies indicated that freezing storage can

a ffect residue characterization. Additional data is

n eeded to support the registrant’s claim that sample
p rocessing occurred immediately following sampling.

835.4300 Aerobic Aquatic Metabolism 41767803 Supplemental / Upgradable Yes P revious studies indicated that freezing storage can

a ffect residue characterization. Additional data is

n eeded to support the registrant’s claim that sample
p rocessing occurred immediately following sampling.

835.4400 Anaerobic Aquatic Metabolism 41767802 Supplemental/ Upgradable Yes P revious studies indicated that freezing storage can

a ffect residue characterization. Additional data is

n eeded to support the registrant’s claim that sample
p rocessing occurred immediately following sampling.-24 of 43- Guideline Study Title MRID Classification Data Gap? Comments

00098518 Unacceptable D ata were too variable to accurately assess the d ecline of asulam. The material balance was i ncomplete, and degradates were not accurately

c haracterized; up to 29% of the applied radioactivity

w as not accounted for. Phys ical parameters of study

w ater were not characterized. The soils were not

c lassified according to the USDA Textural C lassification System.

835.1240 Mobility - Adsorption / Desorption 40965001 Acceptable

No N o significant issues affec ting the acceptability of
t he study were noted.

00084801 Unacceptable T he material balance was incomplete, the purity of
t he test substance is not specified, the CEC of the soil i s not reported, distribution curves of asulam
t hroughout the soil columns are not determined, the
t otal amount of water le ached through each soil

c olumn was not specified.

835.1230 41215101 Acceptable N o significant issues affec ting the acceptability of
t he study were noted.

835.6100 Terrestrial Field Dissipation 00044578 Supplemental/ Upgradeable

Yes T he effects of storage on the recoveries of asulam

a nd its degradation products as well as their subsequent binding to orga nic matter in soil could

n ot be evaluated. Previous studies indicated that f rozen storage can affect residue characterization.

00098527 Unacceptable F ield test data were incomplete, the CEC of the soils

w as not reported. Frozen storage stability data have

n ot been submitted. Residues in the soil immediately f ollowing treatment do not reflect the application

r ates (material was unaccounted for).

00098529 Unacceptable T he application rate was not confirmed by i mmediately following trea tment sampling, residues i n crops and soils were not characterized, soil was

n ot sampled at the time of treatment or planting, and f ield test data were incomplete.

00098530 Unacceptable F ield test data were incomplete, the CEC of the soils

w as not reported, and the soils were not sampled d eep enough to define the extent of leaching.

00114872 Unacceptable T he test substance was not characterized, the soil was i ncompletely characterized, field test data were i ncomplete, the soils were not sampled deep enough
t o define the extent of leaching, storage conditions

w ere not reported, storage stability data were not
p rovided, and residues in th e soil immediately postt reatment do not appear to reflect the application rate.

850.1730 Fish Accumulation 00098511 Unacceptable No R esidues in the water and fish were not

c haracterized; however, this study is not required b ecause the K OW is significantly below 1000.

835.7100 Prospective Groundwater Monitoring 42534501 Supplemental No T his study provided little conclusive information due
t o the problems of residue analysis in the soil; h owever, it is adequate to allow the Agency to

c onclude that asulam is highly mobile and will likely

r each ground water especially under the shallow
g roun d -water conditions.

Non-guideline Drinking Water Monitoring 42704901 Supplemental NA ---25 of 43- 8.2. Effects

The available ecological effects data for asulam /sodium asulam consists primarily of acute effects studies on animals and effects to plants. There are no data on the potential for chronic effects to fish, invertebrates or avian species. There are no acute data on estuarin e/marine fish. Additionally, an avian acute oral study with a passerine is now required under the current 40 CFR Part 158 and is not yet been submitted for asulam . Available data on the toxicity of asulam to terrestrial plants are based on technical sodium asulam rather than the required TEP. Therefore effects to non-target plants may be appreciably underestimated by the available studies. The available effects stud ies for asulam are presented in Tables 8.2-8.4.-26 of 43- TABLE 8.2. Available ecologica l effects data for terrestrial animals exposed to asulam

Guideline Description MRID/ Accession Classification Data Gap? Comments

850.2100 Avian oral toxicity 00056417 Supplemental Yes* *Avian acute oral toxicity data are not available for passerines, which are required under the new 40 CFR Part 158. Therefore, this is identified as a data gap. 850.2200 Avian dietary toxicity 00056418 00056419 Supplemental No

850.2300 Avian reproduction None Yes

850.3020 Honeybee acute contact toxicity 00018842 Acceptable No

TABLE 8.3. Available ecological effects data for aquatic animals exposed to asulam.

Guideline Description MRID/ Accession Classification Data Gap? Comments

850.1075 Freshwater fish – Acute toxicity 40872001 Acceptable

No In the absence of data, risk will be presumed 00098505 Acceptable 00054621 Supplemental

850.1075 Saltwater fish – Acute toxicity None Yes

850.1010 Freshwater invertebrates – Acute toxicity 40977602 Acceptable No 00098507 Acceptable

850.1025 850.1035 Saltwater invertebrates –Acute toxicity 00098508 Acceptable

No 00098509 Acceptable

41000701 Supplemental

850.1300 Freshwater invertebrate – life cycle test None Yes

850.1350 Saltwater invertebrates – life cycle test None Yes

850.1400 Freshwater fish – early life stage test None Yes

850.1400 Saltwater fish – early life stage test Yes-27 of 43- TABLE 8.4. Available ecological effects data for plants exposed to asulam.

Guideline Description MRID Classificatio

n Data Gap? comments

850.4100 Terrestrial Plant toxicity: Tier I seedling
emergence 42613801 Supplemental Yes Data on the phytotoxicity of formulated product with sodium asulam are necessary to estimate the distance to where listed may be affected. 850.4150 Terrestrial Plant toxicity: Tier I vegetative vigor 42613801 Supplemental Yes

850.4400 Aquatic Plant Growth: algae 42560301 Acceptable No

850.4400 Aquatic Plant Growth: vascular plants 42611701 Acceptable No

8. References

Open Literature Citations

Fletcher, J.S., J.E. Nellessen, and T.G. Pfleeger. 1994. Literature review and evaluation of the EPA food-chain (Kenaga) nomogram, an instrume nt for estimating pesticide residues on plants. Environ. Tox. Chem. 13:1383-1391.

Hoerger, F., and E.E. Kenaga. 1972. Pesticide re sidues on plants: Correlation of representative data as a basis for estimation of thei r magnitude in the environment. In F. Coulston and F. Korte, eds ., Environmental Quality and Safety: Chemistry, Toxicology, and Technology, Georg Thieme Publ, St uttgart, West Germany, pp. 9-28.

Pallett, K. E. 2003. Herbicides, Asulam in: Encyclopedia of Agrochemicals. http://dx.doi.org/10.1002/047126363X.agr025

U.S. Fish and Wildlife Service (USFWS) and Na tional Marine Fisheries Service (NMFS). 1998. Endangered Species Consultation Handbook: Procedures for Conducting Consultation and Conference Activities Under Section 7 of the Endangered Sp ecies Act. Final Draft. March 1998.

USEPA. 2004. Overview of the Ecological Risk Assessment Process in th e Office of Pesticide Programs. U.S. Environmental Protection Ag ency, Office of Prevention, Pesticides and Toxic Substances, Office of Pesticide Programs, Washington DC. January 23, 2004.

USEPA, 1995. Reregistration Eligibility Decision, Asulam, List A, Case 0625. http://www.epa.gov/oppsrrd1/REDs/0265.pdf.

USEPA. 1998. Guidelines for Ecological Risk Asse ssment. Risk Assessment Forum, Office of Research and Development, Washi ngton, D.C. EPA/630/R-95/002F. April 1998. http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=30759-28 of 43- Willis, G.H. and L.L. McDowell. 1987. Pestic ide Persistence on Foliage in Reviews of Environmental Contaminati on and Toxicology. 100:23-73.

Submitted Fate Studies

MRID Citation Reference

00098513 Maycey, P.A. and J.B. Unsworth (1981) Asulam: Hydrolysis Studies with Asulam-Ring14C. AG/Tech 56. Unpublished Study Received April 16, 1982 under 359-662; Prepared by May & Baker Ltd., England and Submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, NJ, CDL:070773-B.
40997901 Gohdes, M. (1989) Hydrolysis of ?Carb on 14|-Asulam in Buffered Aqeous Solutions: Proj. ID. HLA 6224-122. Unpublished study prepared by Hazleton Laboratories America, Inc. 62 p. 00084798 Mulcock, P.A. (1971) Asulam: Photos tability Studies: RG/1161. (Un- published study received Nov 8, 1972 under 3F1331; prepared by May & Baker, Ltd., England, submitted by Rhodia, Inc., New Brunsw ick, N.J.; CDL:094626-J)

00097845

or 00047845 Tattersfield, C.R. (1972) Asulam: Photoc hemical Degradation: RG/ 1438. (Unpublished study received Nov 8, 1972 under 3F1331; prepared by May & Baker, Ltd., England, submitted by Rhodia, Inc., New Brunswick, N.J.; CDL:094626-K)
00098514 Williams, C.M. and E.A. Savage (1981) Asulam: Photodegradation in Aqueous Solution. AG/Tech 112. Unpublished Study Received April 16, 1982 under 359-662; Prepared by May & Baker Ltd., England and Submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, NJ, CDL:070773-C.
41326001 Fathulla, R. (1989) Artificial Sunlight Photodegradation of ?Carbon - 14|-Asulam in a Buffered Aqueous Solution: Lab Project Number: HLA/6224/123. Unpublished study prepared by Hazleton Laboratori es America, Inc. 108 p.
00098515 Jones, A.G. and J.B. Unsworth (1981) Asulam: Photodegradation in Soil. AG/Tech 48. Unpublished Study Received April 16, 1982 under 359-662; Prepared by May & Baker Ltd., England and Submitted by Rhone-Poul enc Chemical Co., Monmouth Junction, NJ, CDL:070773-D.
41326002 Obrist, J. (1989) Artificial Sunlight Photodegradation of ?Carbon - 14|-Asulam on Soil: Lab Project Number: HLA/6224/124. Unpublishe d study prepared by Ha zleton Laboratories America, Inc. 96 p.
00098528 Jones, A.G. (1977) Herbicides: Asulam Distribution Studies in Two Loam Soils: AR/1212. (Unpublished study received Apr 16, 1982 under 359-662; prepared by May & Baker Ltd., England, submitted by Rhone-Poulenc Chemic al Co., Monmouth Junction, N.J.; CDL: 070774-B)
00098516 Smith, C.A., J.B. Unsworth and J. Fran klin (1981) Asulam: Metabolism in Soil under Aerobic Conditions. Report No. 1819. Unpublis hed Study Received April 16, 1982 under 0098516; Prepared by May & Baker Ltd., England and Submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, NJ, CDL:070773-E.
00098517 Unsworth, J.B., C.A. Smith and J. Fran klin (1981) Asulam: Metabolism in Soil under Anaerobic Conditions. Report No. AP/1820. Unpublished Study Received April 16, 1982 under 359-662; Prepared by May & Baker Ltd., England and Submitted by Rhone-Poulenc-29 of 43- Chemical Co., Monmouth Junction, NJ, CDL:070773-F.
00084802 Edwards, R.A. (1972a) Asulam: Metabolic Studies with Asulam (Ring 14C). Rg/1433. Unpublished Study Received Nov. 8, 1972 under 3F1331; Prepared by May and Baker, Ltd. England, and Submitted by Rhodia, Inc., New Brunswick, NJ. CDL:094526-O.
41767801 Godward, P.; Fisher, P.; Lowden, P; et al . (1990) Asulam ?carbon 14|: (Na Salt): Aerobic Soil Metabolism ?supplement to MRID 41743301|: Lab Project Number P88/086: P90/385. Unpublished study prepared by Rhone-Poulenc Agriculture. 139 p.
41767803 Gowdard, P.; Fisher, P.; Lowden, P.; et al . (1991) Asulam ?carbon 14| (Na Salt): Aerobic Aquatic Soil Metabolism ? supplement to MRID 41743303 |: Lab Project Number: P89/217. Unpublished study prepared by Rhone-Poulenc Agriculture. 122 p.
41767802 Godward, P.; Fisher, P.; Lowden, P.; et al. (1991) Asulam ?carbon 14|: (Na-Salt): Anaerobic Aquatic Soil Metabolism ?supplement to MRID 41743302|: Lab Project Number: P88/087: 162-3. Unpublished study prep ared by Rhone-Poulenc Agriculture. 112 p. 00098518 Turner,G.M.., J.B. Unswor th and J. Franklin (1981) Asulam: Metabo lism in Pond and River Sediments (Anaerobic Aquatic). AG/Tech 52. Unpublished Study Received April 16, 1982 under 359-662; Prepared by May & Baker Ltd., England and Submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, NJ, CDL:070773-G.
00056428 Hewett, R.H. ( 1971) Asulam (Herbicide): Soil Mob ility and Soil Persistence Studies Using Bioassay Techniques: Ongar 1971: Report No . AR 651. (Unpublished study received Jun 11, 1972 under 2G1200; prepared by May & Baker, Ltd., submitted by Rhodia, Inc., New Brunswick, N.J.; CDL:091017-AE)
00056429 Guardigli, A. (1971) Leaching Studies on Asulam: Laboratory Exper- iments. (Unpublished study received Jun 11, 1972 under 2G1200; s ubmitted by Rhodia, Inc., New Brunswick, N.J.; CDL:091017-AF)
00113839 Jones, A. (1977) Herbicides: Asulam--Di stribution Studies in Two Loam Soils: AR/1212. (Unpublished study received May 4, 1977 under 359-662; prepared by May & Baker, Ltd., Eng., submitted by Rhone-Poulenc, Inc ., Monmouth Junction, NJ; CDL:230626-A)
00127712 Nomura, N. (1978) Adsorption and Mobilit y of VEL 5026-14C in Five Hawaiian Sugarcane Soils. (Unpublished study received Aug 21, 1978 under 876-EX-36; prepared by Hawaiian Sugar Planters' As- soc., submitted by Ve lsicol Chemical Corp., Chicago, IL; CDL: 234819-H)
00098525 Cooper, I.C. and J.B. Unsworth (1981) Asulam: Leaching Study with Four Soils. AG Tech. 19. Unpublished Study Received Apr. 16, 1982 under 359-662; Prepared by May and Baker and Baker, Ltd., England, and Submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, NJ ; CDL:070773-N.
00098526 Savage, E.A. and P.I. Podwar d. 1981. Asulam Sorption study with Four Soils : AG Tech. 27. Unpublished Study Received Apr. 16 , 1982 under 359-662; Prepared by May and Baker, Ltd., Submitted by Rhone-Poulenc C hemical Co., Monmouth Junction, NJ; CDL: 070773-0.
00134842 Nomura, N. (1978) Adsorption and Mobilit y of VEL 5026-14C in Five Hawaiian Sugarcane Soils. (Unpublished study received July 12, 1978 under 876-EX-35; Prepared by Hawaiian Sugar Planters' Assoc. and submitted by Ve lsicol Chemical Corp., Chicago, IL; CDL: 234423-J).
40965001 Reeves, G.; England, D.; Savage, E. (1988) Herbicides: Asulam-?Car- bon 14|: Leaching Study with Four Soils: Laboratory Project ID : D. Ag. 1118. Unpublished study prepared by Rhone-Poulenc Agri- culture. 83 p.-30 of 43- 41215101 Godward, P.; England, D.; Savage, E. (1988) Herbicides: Asulam - ?carbon 14| (Na Salt) Adsorption/Desorption on Five Soils: Pro- je ct ID: D.Ag.1119. Unpublished study prepared by Rhone-Poulenc Agriculture. 82 p.
00044578 Cooley, A.W.; Harper, D.; Burr, R.; et al . (1975) Residue Study of Asulam, Its Impurity and Metabolites in/on Alfalfa Forage and Soil: Report No. 75/107/NB/AG. (Unpublished study received Dec 17, 1975 under 6F1716; prepared in cooperation with Oregon State Univ., submitted by Rhodia, Inc., New Brunswick, N.J.; CDL: 095193-C)
00098527 Guyton, C.L.; Chow, W.; Guardigli, A. (1981) Asulam Residue Data on Soil Treated PPI in 1976 and 1977: PDD No. 81/017. (Unpub- lished study received Apr 16, 1982 under 359- 662; submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, N.J.; CDL: 070774- A)
00098529 Jones, A.G. (1981) Asulam: Residues in Crops Grown in Soil Treated with Asulam- ?~ring~?^14IC: AG.Tech/55. (Unpublished study re- ceived Apr 16, 1982 under 359-662; prepared by May & Baker Ltd., England, submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, N.J.; CDL:070774-C)
00098530 Guyton, C.L.; Somma, N.; Guardigli, A. (1982) Asulam Residue Data on Crops and Soil from a Long Term Persistence Study: 1976-197 9: PDD No. 82/027. (Unpublished study received Apr 16, 1982 under 359-662; submi tted by Rhone-Poulenc Chemical Co., Monmouth Junction, N.J.; CDL:070774-D)
00114872 Rhodia, Inc. (1975) Residue Study of As ulam and Metabolites in Field Sugar Cane Soil. (Compilation; unpublished study received Apr 11, 1975 under 3F1331; CDL:094625-A)
42534501 Norris, F. (1992) A Small Scale Prospect ive Groundwater Monitoring Study with AsulamSodium, the Active Ingredient of Asulox Br and Herbicide Applied to Sugar Cane and to Turf: Progress Report: Lab Project Number: EC-89-068: EC/89/069: 920105. Unpublished study prepared by Rhone-Poulenc. 17 p.
41803901 Norris, F. (1991) A Small Scale Prospect ive Groundwater Monitoring Study with AsulamSodium, the Active Ingredient of Asulox Br and Herbicide, Applied to Sugar Cane and to Turf: Lab Project Num- ber: 40949: EC-89-06 8: EC-89-069. Unpubl ished study prepared by Rhone-Poulenc Ag Co., A & L Eastern Ag ricultural Laboratories, Inc., Analytical Development Corp., and CYAL. 180 p.
42704901 Gustafson, D. (1993) Drinking Water Monitoring for Residues of Asulam in High-use Areas of the United States: Lab Project Number: 41293: EC-91-153. Unpublished study prepared by Alta Analytical Laboratory, Inc. 164 p.

Submitted Effects Studies

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference

56417 Ingham, B. (1971) Herbicides: Asulox 40: Acute Oral Toxicity in Mallard, Partridges, Pheasants and Pigeons: Report No. RG/1108. (Unpublished study received Jun 11, 1972 under 2G1200; prepared by May and Baker, Ltd., England, submitted by Rhodia, Inc., New Brunswick, N.J.; CDL:091017-T)-31 of 43- 71-2 Avian Dietary Toxicity

MRID Citation Reference

56418 Heywood, B.A.; Ingham, B. (1970) Asul ox: Subacute (5 Day) Toxicity in Mallard Ducklings: Report No. RG/857. (Unpublished study received Jun 11, 1972 under 2G1200; prepared by May and Baker, Ltd., England, submitted by Rhodia, Inc ., New Brunswick, N.J.; CDL:091017- U)
56419 Heywood, B.A.; Ingham, B. (1970) As ulox: Subacute (5 Day) Toxicity Study in Pheasant Chicks: Report No. RG/867. (Unpublished study received Jun 11, 1972 under 2G1200; prepared by May and Baker, Ltd., England, submitted by Rhodia, Inc ., New Brunswick, N.J.; CDL:091017- V)

72-1 Fish Acute Toxicity

56421 Fraser, W.D.; Jenkins, G. (1970) The Acute Toxicity of Asulam to Rainbow Trout, Goldfish, Channel Catfish and Bluegill: Report No. 3639/70/451. (Unpublished study rece ived Jun 11, 1972 under 2G1200; prepared by Huntingdon Research C entre, England, sub- mitted by Rhodia, Inc., New Brunswick, N.J.; CDL:091017-X)
98505 Vilkas, A.G.; Kuc, W.J. ( 1979) The Acute Toxicity of As ulam Tech- nical to the Bluegill Sunfish~Lepomis macrochirus~Rafines que: UCES Project No. 11506-48-06. (Unpublished study received Apr 16, 1982 under 359-662; prepared by Union Carbide Corp., submit- ted by Rhone-Poulenc Ch emical Co., Monmouth Junction, N.J.; CDL:070772-A)
40872001 Manning, C. (1988) Acute Toxicity of Asulam Technical to Rainbow Trout (Salmo gaidneri) Under Static Conditions: Proj ect ID: ese No. 89325-0400-2130. Unpublished study prepared by Hunter/ ESE, Inc. 76 p.-32 of 43- 72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference

98507 Roberts, S.; Parke, G.S.E.; Charles, S. ( 1977) Static 48-hour Toxicity Study of Asulam Technical in Daphnids: Laboratory No. 7E-7665. (Unpublished study received Apr 16, 1982 under 359-662; prepared by Cannon Lab oratories, Inc., submitted by RhonePoulenc Chemical Co., Monmouth Junction, N.J.; CDL: 070772-C)
40977602 Manning, C. (1988) Asulam Technical: Acute Toxicity to the Water Flea (Daphnia magna) Under Flow-Through Conditions: Proj. ID ESE No. 89325-0200-2130. Unpublished study prepared by Hunter/ ESE, Inc. 73 p.

72-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

98508 Vilkas, A.G.; Schneider, C.E. (1979) The Ac ute Toxicity of Asulam Technical to the Grass Shrimp, Palaemonetes pugio: UCES Project No. 11506-48-05. (Unpublished study received Apr 16, 1982 under 359-662; prepared by Union Carbide Corp., submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, N.J.; CDL: 070772-D)
98509 Schneider, C. (1979) The Acute Toxicity of Asulam Technical to the Fiddler Crab Uca pugilator: UCES Project No. 11506-48-04. (Unpublished study received Apr 16, 1982 under 359-662; prepared by Union Carbide Corp., submitted by Rhone-Poulenc Chemical Co., Monmouth Junction, N.J.; CDL:070772-E)
41000701 Manning, C. (1989) Asulam Technical: Acut e Effect to New Shell Growth of the Eastern Oyster (Crassostrea virginica) Under Flow - through Conditions: Proj. ID 89325-0300- 2130. Unpublished st udy prepared by H unter/ESE. 94 p.

123-1 Seed germination/seedling emergence and vegitative vigor

MRID Citation Reference

42613801 Christensen, K. (1992) Asulam Sodium--Determination of Effects on Seed Germination, Seedling Emerge nce and Vegetative Vigor of Ten Plant Species: Final Report: Lab Project Number: 92-9-4431: 10566.0292.6217.610. Unpublished study prepared by Springborn Labs., Inc. 214 p.
43844601 Hoberg, J. (1995) Asulam Sodium--Determination of Effects on Seed Germination and Vegetative Vigor of Several Plant Species: Supplement to Final Report: Lab Project Number: 95-3-5751: 10566.0292.6217.610. Unpublished study prepared by Springborn Labs, Inc. 94 p.-33 of 43- 123-2 Aquatic plant growth

MRID Citation Reference

42560301 Hoberg, J. (1992) Asulam Sodium--Toxicity to the Freshwater Green Alga, Selenastrum capricornutum: Final Report: Lab Project Number: 92-8-4391: 10566.0292.6220.430. U npublished study prepared by Springborn Labs, Inc. 61 p.
42560302 Hoberg, J. (1992) Asulam Sodium--Toxicity to the Marine Diatom, Skeletonema costatum: Final Report: Lab Project Number: 92-8-4395: 10566.0292.6221.450. Unpublished study prepared by Springborn Labs, Inc. 59 p.
42611701 Hoberg, J. (1992) Asulam Sodium--Toxicity to the Duckweed Lemna gibba: Final Report: Lab Project Number: 92-9-4397: 10566.0292.6222.410. Unpublished study prepared by Springborn Labs, Inc. 64 p.
42613802 Hoberg, J. (1992) Asulam Sodium--Toxicity to the Freshwater Alga, Anabaena flos-aquae: Final Report: Lab Project Number: 92-10-4457: 10566.0292.6218.420. Unpublished study prepared by Springborn Lab., Inc. 60 p.
42631301 Hoberg, J. (1992) Asulam Sodium--Toxicity to the Freshwater Diatom, Navicula pelliculosa: Final Report: Lab Project Number: 92-12-4519: 10566.0292.6219.440. Unpublished study prepared by Springborn Labs, Inc. 60 p.-34 of 43- APPENDIX A. Data Call-in Tables

Study Title: Aerobic soil metabolism Guideline Numb er: 835.4100 Study Substance: Na-asulam Rationale for Requiring the Data Per 40 CFR part 158, promulgated July 1, 2009, requires aerobic soil metabolism data for pesticide food and nonfood terrestrial uses. Currently the Agency has received one s upplemental study on three soil types (MRID 41767801). An acceptable soil is required per OCSPP guideline 835.4100. Aero bic soil metabolism studies facilitate an understanding of a compound’s degradation in the soil under aerobic conditions in the laboratory. Depending on how quickly, to what extent, and to which transformation products the com pound degrades, Na-asulam may or may not pose potential exposure concern. Previous studies indicated that freezing storage can affect residue characterization. Additional data is needed to support the registrant’s claim that sample processing occurred immediately following sampling. Practical Utility of the Data How will the data be used? Additional aerobic soil metabolism data will facilitate a better understanding of the fate of Na-asulam residues in soil, in order to characterize the variability in the degradation of Na-asulam in different soil types. If data indicate that degradation in aerobic soil occurs rapidly and produces nontoxic transformation products, then the Agency could potentially determine that Na-asulam residues of concern do not persist in soil under aerobic conditions. If data indicate that degradation is not appreciable in soil or that the transformation products are of similar or higher toxicity than the parent compound, then the Agency could conclude that Na-asulam residues of concern persist in soil under some aerobic conditions.

How could the data impact the Ag ency’s future decision-making? If the required data indicate that Na-asulam in aerobic soils is rapidly biodegraded to nontoxic transformation products, then risk assessment conclusions and associated la beled use precautions and/or restrictions could be made less restrictive. The lack of these data will limit the flexib ility the Agency and registrants have in complying with the Endangered Species Act and could result in use restri ctions for Na-asulam which are unnecessarily severe.

Study Title: Aerobic aquatic metabolism Guideline Numb er: 835.4300 Study Substance: Na-asulam Rationale for Requiring the Data Per 40 CFR part 158, which was promulgated on July 1, 2009, states an aerobic aquatic metabolism study is required due to Na-asulam being applied to terrestrial crops. Two sediment: water systems are required per the guideline, currently one supplemental system has been submitted. Aer obic aquatic metabolism studies facilitate an understanding of a compound’s degradation in the water column or sediment under aerobic (oxygen-rich) conditions in the laboratory. These studies are generated by pesticide intera ction with microorganisms in a water/sediment system. Depending on how quickly, to what extent, and to which transformation products the compound degrades, Na-asulam may or may not pose potential exposure concern in water. Because Na-asulam degradation in water is not well understood, the Agency is requiring data. Previous studies indicated that freezing storage can affect residue characterization. Additional data is needed to support th e registrant’s claim that sample processing occurred immediately following sampling. Practical Utility of the Data How will the data be used? Aerobic aquatic metabolism data will facilitate a better understanding of the fate of Na-asulam residues in water. If data indicate that degradation in aerobic conditions occu rs rapidly in water and produces nontoxic transformation products, then the Agency could potentially determine that Na-asulam residues of concern do not persist in water under aerobic conditions. If data indicate that degradatio n is not appreciable in wate r or that the transformation products are of similar or higher toxicity than the parent compound, then the Agency could conclude that Na-asulam residues of concern persist in water under aerobic conditions.

How could the data impact the Ag ency’s future decision-making?-35 of 43- In absence of these data, conservative as sumptions will be made (3x the single va lue), Therefore, potential for risk to aquatic organisms may be overestimated and the use of Na-asulam might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in complying with the Endangered Species Act and coul d result in use restrictions for Na-asulam which are unnecessarily severe.

Study Title: Anaerobic Aquatic Metabolism Guideline Number: 835.4400 Study Substance: Na-asulam Rationale for Requiring the Data Acceptable data have not been provid ed to quantify the metabolism of Na-a sulam under anaerobic aquatic conditions; supplemental data has been submitted. According to 40 CFR Part 158 Subpart N, July, 2009 (data requirements for pesticides) anaerobic aquatic metabolism in two water:sediment systems are required for pesticides with terrestrial or aquatic food and nonfood uses. Since Na-asulam uses are cl assified as terrestrial, anaerobic aquatic metabolism data for Na-asulam should be submitted to fulfill OCSPP Guideline 83 5.4400. Previous studies indicated that freezing storage can affect residue characterizatio n. Additional data is needed to support the registrant’s claim that sample processing occurred immediately following sampling. Practical Utility of the Data How will the data be used? Currently there are no acceptab le anaerobic aquatic metabolism studies thattrack the formation and decline of Naasulam and its degradates. The submitted data will be used to characterize and quantify the environmental fate of Naasulam and its degradates in aquatic environments. For qu antitative exposure estimation, these data will be used to confirm the conceptual model of Na-asulam fate and transport in aquatic environments.

How could the data impact the Ag ency’s future decision-making? Without these required data, the fate of Na-asulam cannot be fully characterized and exposure to potentially toxic degradates cannot be quantified. The persistence of as ulam and its degradates to which terrestrial and aquatic organisms will be exposed to is uncerta in. In the absence of acceptable data , conservative assumptions will be made regarding the potential for formation of Na-asulam degradates. Therefore, potential for risk to aquatic organisms may be overestimated and the use of Na-asulam might need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in complying with the Endangered Species Act and could result in use restri ctions for Na-asulam which are unnecessarily severe.

Study Title: Terrestria l Field Dissipation Guideline Number: 835.6100 Study Substance: Na-asulam Rationale for Requiring the Data The Agency has not received an acceptab le terrestrial field dissipation study for Na-asulam, examining current use rates. Pursuant to 40 CFR part 158, Subpart N, terrestrial field dissipation studies (OCSPP guideline 835.6100) are required for all terrestrial food and nonfood pesticide uses. Field dissipation studies are the only means by which laboratory generated data used in models can be validated. Significant departures from field estimated and laboratory estimated half-lives can indicate weaknesse s in data and mischaracterizations of physical-chemical properties. EFED recommends that a terrestrial field dissipation study be conducted for the representative use areas for Na-asulam. Practical Utility of the Data How will the data be used? No terrestrial field dissipation study that adequately tracks the formation and decline of Na-asulam and its degradates is currently available and the additional data will be used to characterize the environmental fate of Na-asulam. For quantitative exposure estimation, these data will be used to confirm the conceptual model of Na-asulam fate and transport in the environment.

How could the data impact the Ag ency’s future decision-making? Without these required data, the fate of Na-asulam cannot be fully characterized and exposure to potentially toxic degradates cannot be quantified. The persistence of Na-asulam and degradates to which terrestrial and aquatic-36 of 43- organisms will be exposed to is uncerta in. In the absence of acceptable data , conservative assumptions will be made regarding the potential for formation of Na-asulam degradat es. The lack of these data will limit the flexibility theAgency and registrants have complying with the Endangered Species Act and could result in use restrictions for Naasulam which are unnecessarily severe.

Guideline Numb er: 835.6100 Study Title: Frozen Storage Stability Study Substance: Na-asulam Rationale for Requiring the Data The Agency has a limited understanding of how Na-asulam behaves in frozen storage conditions between the time of sampling and the time of analysis. Previous studies have indicated that storage under frozen conditions results in some amount of material loss between sampling and the time of analysis. Submission of a storage stability study is essential in order to be confident that any degradation measured in the test system was due solely to the environment of that test system, and not due to handling and storage. Practical Utility of the Data How will the data be used? Storage stability data will facilitate a better understanding of the fate of Na-asulam residues during storage and handling between sampling and analysis. If data indicate that degradation of Na-asulam or its degradates occur then the data from the field studies are no longer valid as it woul d not be feasible to determine if the degradation measured in the test system was due solely to the environment of that test system, and not due to handling and storage.

How could the data change the Agency’s decision or impact the Agency’s future decision-making? In the absence of the required data, the field data, as we ll as much of the laboratory data for Na-asulam will be qualitatively used in the risk assessment. These data are us ed for confirmatory data to ensure that any degradation observed in the test systems is due solely to th e test environment and not handling or storage.

Study Title: Analytical Methods (and Associated Indepe ndent Laboratory Validations) for Residues in Water, Sediment, and Soil Guideline Number: 835.6100 Study Substance: Na-asulam Rationale for Requiring the Data Independently validated analytical methods for residues in water, sediment, and soil (environmental chemistry methods) submitted by the registrant are used to evaluate analyses describe d in submitted environmental fate and ecological effects studies. Submitted analytical methods are also used by various Federal, State, Tribal, and local agencies to detect and monitor residues that are or are suspected to be in e nvironmental compartments due to outdoor uses and accidental releases. Independ ent laboratory validations for submitte d analytical methods are necessary to confirm that the methods are functional an d to confirm the levels of detection and quantitation reported in registrantprepared validations.

Use of Na-asulam may impact surface water quality due to ru noff of rain water and drift of residues. This is especially true for poorly draining soils, erodible soils , and soils with shallow ground water. Na-asulam has a potential for reaching both surface water and aquatic sedime nt via runoff, it also has similar characteristics to chemicals detected in ground water. Therefore, outside agencies may request analytical methods with which to monitor for Na-asulam residues in water and in soil or sediment. Practical Utility of the Data How will the data be used? In the absence of independently validated environmental chemistry methods, submitted environmental fate and ecological effects data may not be reviewable and entities outside the Agen cy may lack chemical-specific methods for analyses in environmental compartments. Independently va lidated environmental chemistry methods will be used to evaluate any newly submitted environmental fate and ecological effects data and will be made available for enforcement and monito ring purposes at the federal, state, and local levels.

How could the data impact the Ag ency’s future decision-making?-37 of 43- Without these required data, the fate of Na-asulam cannot be fully characterized and exposure to potentially toxic degradates cannot be quantified. The persistence of Na -asulam and potential degradates to which terrestrial and aquatic organisms will be exposed to is uncertain. In th e absence of acceptable data, c onservative assump tions will be made regarding the potential for formation of Na-asulam degradates. Therefore, potential for risk to aquatic organisms may be overestimated and the use of Na-asulam might need to be restricted in areas where endangered species could be exposed. The lack of these data will lim it the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and coul d result in use restrictions for Na-asulam which are unnecessarily severe.

Guideline Number: 850.2100 Study Title: Avian Acute Oral Toxicity Test Rationale for Requiring the Data Supplemental acute avian oral toxicity data for asulam were submitted for several species of birds; however, data are not available for a passerine species, which is now required under the 40 CFR Part 158 (CFR 40 2007) data requirements for conventional pesticides. The Part 158 data requirements specify that acute avian oral toxicity data be submitted for either mallard duck or bobwhite quail and a passe rine species. Therefore, an avian oral toxicity test is required for passerine birds, as specified in 40 CFR Part 158. A passerine study protocol must be submitted for review by the Agency prior to initiation of this study. Practical Utility of the Data How will the data be used? Acute avian oral toxicity data for passerine species w ill be used to refine the screening-level assessment by determining whether there are differences in avian species sensitivity to asulam between passerines and species of other orders. If oral acute toxicity data are not submitted for passerines, risk will be assumed for all passerine species.

How could the data impact the Ag ency’s future decision-making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that asulam “may affect” listed birds directly (and listed species from other taxa indirectly), and use of asulam and its formulated products may need to be re stricted in areas where listed species co uld be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for asulam use that are unnecessarily severe.

Guideline Number: 850.4225, 4250 Study Title: Terrestrial Plant Toxicity Test Rationale for Requiring the Data Data regarding the toxicity of formulated sodium asulam to terrestrial plants are un available and required under 40CFR Part 158. Data on technical grade sodium asulam i ndicates effects to terrestrial plant species two orders of magnitude below the maximum label rates, and formulated product is expected to be more toxic than TGAI Practical Utility of the Data How will the data be used? Vegetative vigor and seedling emergence data for terrestrial plants will be used to determine the spatial extent to which sodium asulam will affect non-target plant species in terrestrial environments. Additionally, these data will be used to determine the spatial extent of indirect effects to listed taxa.

How could the data impact the Ag ency’s future decision-making? If future endangered species risk assessments are perfor med without these data, the Agency may have to employ conservative assumptions regarding the toxicity of formulated product. Therefore, use of sodium asulam and its formulated products may need to be rest ricted in areas where listed species coul d be exposed. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for so dium asulam that are unnecessarily severe.

Guideline Number: 850.2300 Study Title: Avian Reproduction Rationale for Requiring the Data-38 of 43- Avian reproduction toxicity data are not available for the assessment of chronic exposure of birds to sodium asulam; these data are required under the 40 CFR Part 158 for pes ticides with outdoor uses. These data are necessary to determine the reproductive toxicity of sodium asulam to avian species from chronic exposure. Practical Utility of the Data How will the data be used? Avian reproduction toxicity data for mallard ducks will be used in the screening-level assessment to determine whether there are effects on birds from chronic exposure to sodium asulam. If reproductive toxicity data are not submitted, risk will be assumed for all avian species.

How could the data impact the Ag ency’s future decision-making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that sodium asulam “may affect” listed birds directly (and listed species from other taxa indirectly), and use of sodium asulam products may need to be restricted in areas where lis ted species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in co ming into compliance with the Endangered Species Act and could result in use restrictions for isox aben use that are unnecessarily severe.

Guideline Number: 850.1350, 1400 Study Title: Aquatic Invertebrate Li fe Cycle and Fish Early Life Stage Rationale for Requiring the Data

Chronic invertebrate life cycle and chro nic fish data are required under 40 CFR Part 158 data requirements for pesticides with outdoor uses. These data are necessary to determine if chronic exposure to isoxaben may adversely affect the survival, growth or reproduction of aquatic species. Practical Utility of the Data How will the data be used? These data are necessary to characterize the potential risks from sodium asulam to aquatic animals. Chronic exposure data will be used in the screening-level risk assessment to estimate the scope of sublethal effects and potential chronic risks to fish and aquatic invertebrates from the uses of s odium asulam. In the absence of these data, the Agency will presume risk to these taxa from chronic exposure to sodium asulam.

How could the data change the Agency’s decision or impact the Agency’s future decision-making? If future endangered species risk assessments are performed without these data, the Agency would have to assume that sodium asulam “may affect” listed species directly (and lis ted species from other taxa indirectly), and use of sodium asulam products may need to be restricted in areas where lis ted species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in co ming into compliance with the Endangered Species Act and could result in use restrictions for sodium asulam use that are unnecessarily severe.-39 of 43- Appendix B Summary of available effects studies

All endpoints are reported in terms of asulam acid except terrestrial plants , which are reported in terms of sodium asulam.

I. Aquatic Organisms

Some aquatic toxicity studies we re conducted with co-solvents. Given the solubility of asulam in water, it is unclear why solvents were used in these studies; however, the use of the solvents did not appear to impact the study results.

Freshwater fish

An acceptable 96-hr acute toxicity study with the rainbow trout ( Oncorhynchus mykiss ) is available for asulam (MRID 40872001). The fish were exposed to mean-measured concentrations of 0 (control), 20, 37.5, 61, 100 and 175 mg ae/L. No effects were reported at any concentration and the LC 50 is reported to be >175 mg ae/L.

An acceptable study with bluegill sunfish ( Lepomis macrochirus ; MRID 00098505) is available for asulam. Bluegill were exposed to mean-meas ured concentrations of 0 (negative and solvent controls), 18, 32, 56, 100 and 180 mg ae/L. Dimet hylformamide (DMF) was used as a solvent. No effects were reported at any concentration and the LC 50 is reported to be >180 mg ae/L.

As a result of these studies, asulam is classifi ed as practically nontoxic to freshwater fish on an acute exposure basis.

Supplemental data are available for the toxicity of formulated asulam to fish (MRID 00054621). Rainbow trout, bluegill, goldfish ( Carassius auratus ) and channel catfish ( Ictalurus punctatus ) were exposed to concentrations of 0 (c ontrol) 648, 1080, 1800, 3000 and 5000 mg ae/L. No mortalities were reported fo r any species at any con centration, therefore the LC 50 for each of the species was reported as >5000 mg ae/L.

Freshwater invertebrates

An acceptable 48-hr acute study with the freshwater invertebrate Daphnia magna is available for asulam (MRID 40977602). Twenty daphnids per level were exposed at mean measured concentrations of 0 (negativ e control), 9.3, 17.5, 25.5, 48.5 and 83 mg ae/L. Immobility was 0, 0, 0, 0, 45 and 55% respectively. The EC 50 for this study was found to be 67 mg ae/L with a probit slope of 4.1.-40 of 43- A second acceptable study (MRID 00098507) exposed da phnids at measured concentrations of 0 (negative and solvent co ntrols), 10, 20, 32, 56, 80, 96 and 110 mg ae/L. Acetone was used as a solvent. Immobility ranged from 25% at 10 mg ae/L to 100% at 110 mg ae/L, with an EC 50 determined to be 27.1 mg ae/L with a probit slope of 2.2.

Based on these studies, asulam is classified as slightly toxic to freshw ater invertebrates on an acute exposure basis.

Estuarine/marine fish

There are no data assessing the effect of asulam on estuarine/marine fish

Estuarine/marine invertebrates

An acceptable study with asulam (97%) was conducted on the estuarine/marine grass shrimp ( Palaemonetes pugio ; MRID 00098508) at nominal concentra tions of 0 (negative and solvent controls), 10, 18, 32, 56 and 100 mg ae/L. Acetone wa s used as solvent, but appeared to have no effect on the results. No eff ects were reported at any of the test concentrations and the LC 50 was determined to be >100 mg ae/L.

An acceptable study with fiddler crab ( Uca pugilator ; MRID 00098509) was conducted at nominal technical asulam (97%) concentrations of 0 (negative and solvent controls), 10, 18, 32, 56 and 100 mg ae/L. Acetone was used as solvent. No effects were reported at any of the test concentrations and the LC 50 was determined to be >100 mg ae/L.

Based on these studies, asulam is classified as practically nontoxic to estuarine/marine invertebrates on an acute exposure basis.

A supplemental study assessing the effect of asulam on the shell growth growth of Eastern oyster ( Crassostrea virginica MRID 41000701) is available. Oysters were exposed to mean measured concentrations of 0 (control), 21.5, 40, 64.5, 105 and 185 mg ae/L. No effects were seen at any concentration; therefore the EC 50 is determined to be >185 mg ae/L and the NOAEC is 185 mg ae/L.

Plants

One guideline study (MRID 42611701; Acceptable) is av ailable assessing the toxicity of asulam to the aquatic vascular plant duckweed ( Lemna gibba ). Duckweed was exposed to initial measured concentrations of asulam of 0 (control) 0.035, 0.065, 0.12, 0.26 and 0.44 mg ae/L. The 14-day EC 50 , based on frond number, is 0.14 mg ae/L and the NOAEC is 0.07 mg ae/L.

Four guideline studies are availa ble assessing the toxicity of asulam to aquatic nonvascular plants. The green algae Pseudokirchneriella subcapitata (formerly known as Selanastrum capricornutum ) was exposed to mean-measured concentr ations of asulam of 0(control) 0.02, 0.049, 0.12, 0.29, 0.71 and 1.9 mg ae/L. The 96-hour EC 50 , based on cell density, is 0.18 mg ae/L and the NOAEC is 0.02 mg ae/L (MRID 42560301; Acceptable).-41 of 43- The cyanobacteria Anabaena flos aqua (MRID 42613802; Acceptable) was exposed to meanmeasured concentrations of asulam of 0(control) 0.023, 0.045, 0.089, 0.19, 0.37 and 0.72 mg ae/L. The 96-hour EC 50 , based on cell density, is 0.70 mg ae/ L and the NOAEC is 0.09 mg ae/L.

The diatom Skeletonema costatum (MRID 42560302; Acceptable) was exposed to meanmeasured concentrations of asulam of 0(control) 0.022, 0.058, 0.13, 0.33, 0.74 and 1.8 mg ae/L. The 96-hour EC 50 , based on cell density, is 0.44 mg ae/L and the NOAEC is 0.02 mg ae/L.

The diatom Navicula pellicosa (MRID 42631301; Acceptable) was exposed to mean-measured concentrations of asulam of 0(control) 0.15, 0.30, 0.54, 1.3, 2.1 and 4.4 mg ae/L. The 96-hour EC 50 , based on cell density, is 2.3 mg ae/L and the NOAEC is 0.15 mg ae/L.

II. Terrestrial Organisms

Avian

There are no guideline avian acu te oral or subacute dietary toxicity studies for asulam.

The acute oral toxicity of formulated asulam (40%) was studied in several avian species (MRID 00056417; Supplemental). Partridge ( Perdix perdix ), mallard duck ( Anas platyrhynchos ), pheasant ( Phasianus colchicus ) and pigeons ( Columba livia ) were exposed to formulated asulam at doses of 0 (control), 1600, 2600 and 4000 mg ae/kg-bw. One ma llard mortality was reported at the 4000 mg ae/kg-bw dose, but no other effect s were observed. No mortalities or other effects were reported for pheasant or pigeons. Seven partridge mortalities were reported at 4000 mg ae/kg-bw, and one mortality in both of the other doses and the control. The LD 50 for birds, based on the partridge, is 3674.5 mg ae/kg-bw. Asulam is classified as practically nontoxic to avian species on an acute oral exposure basis.

The 5-day subacute dietary toxicity of form ulated asulam (60%) was studied in mallard ducklings (MRID 00056418; Supplemental). There were two parts to the mallard study, one testing up 75000 mg ae/kg-diet a nd another testing up to 100000 mg ae/kg-bw. Ten ducklings (7 days old) per level were exposed to nomi nal concentrations of 0 (control), 10000, 15000, 22500, 33750, 50000, 75000 and 100000 mg ae/kg-diet. There was a single control mortality in part one of the study and two mortalities (on different da ys) at the 75000 mg ae/kg- diet concentration in the second part. The LC 50 for the study is >75000 mg ae/kg- diet. No other effects were reported. Studies with DDT were concurrently conducted but had no imp act on the inferences drawn from the asulam study.

The 5-day subacute dietary toxicity of formulat ed asulam (60%) was studied in pheasant chicks (MRID 00056419; Supplemental). In two studies, te n pheasants (7 day old) per level were exposed to nominal concentrations of 0 (control), 10000, 15000, 22500, 33750, 50000 and 75000 mg ae/kg-diet. No mortalities or sublethal effect s were reported at any concentration in either study. Based on these data, the LC 50 is greater than 75000 mg/kg. Therefore, asulam is classified as practically nontoxi c to birds on a subacute dietary basis. Studies with DDT were concurrently conducted but had no impact on the inferences drawn from the asulam study.-42 of 43- Mammals

Mammal toxicity data are draw n from the Health Effects Divi sion (HED) chapter in support of the RED. The data are summarized below.

Acute

Toxicity testing with the TGAI (88% asulam) produced an acute oral LD 50 >5000 mg ae/kg-bw. Based on these data, asulam is classified as practically nontoxic to mammals on an acute exposure basis (MRID 42110001, 40960501).

Chronic Toxicity

A two-generation rat reproduction study (MRID 00098540) was conducted at nominal concentrations of 0 (control), 1000, 5000, a nd 25000 mg ae/kg-diet and produced a NOAEL of 1000 mg ae/kg-diet (50 mg ae/kg-bw/day). Th e LOAEL was 5000 ppm based on reduction in number of live births per litter. Other eff ects in the study included decreased body and organ weight in the parents at 25000 mg ae/kg-diet concentration.

Terrestrial Invertebrates

An acute contact study with young adult honeybees ( Apis mellifera ; MRID 00018842) reports 4.9% mortality at 36.26 μg ae/bee after 96 hours, wh ich indicates asulam is practically nontoxic to honeybees. However, there are no data associ ated with the study, which is an investigation into multiple pesticides.

Plants

The toxicity of asulam sodium to terrestrial plant seedling em ergence and vegetative vigor was assessed in separate studies reported under MRID 42613801 (Supplemental). The studies were conducted with technical asulam sodium rather than typical end use pr oduct as required under 40 CFR Part 158. Herbicidal active in gredients are usually formulated with adjuvants or surfactants that enhance the activity of the pesticide. Therefore, the sensitivity of terrestrial plants to asulam may be underestimated.

For seedling emergence, cabbage ( Brassica oleracea ) and oat (Avena sativa) were tested at measured concentrations of 0 (cont rol), 0.099, 0.19, 0.40, 0.73, 1.7 lbs ai/A, corn ( Zea mays ), cucumber ( Cucumis sativus ), soybean ( Glycine max ) and tomato ( Solanum lycopersicum ) were tested at measured concentrations of 0 (control), 0.40, 0.73, 1.7, 3.0 and 6.6 lbs ai/A. Onion ( Allium cepa ) was tested at measured concentrat ions of 0 (control), 0.19, 0.40, 0.73, 1.7, 3.0 lbs ai/A, ryegrass ( Lolium perenne ) at 0 (control), 0.050, 0.099, 0.19, 0.40, 0.73 lbs ai/A, radish ( Raphanus sativus ) at 0 (control), 0.050, 0.099, 0.19, 0.40, 0.73, 1.7 lbs ai/A. Lettuce ( Lactuca sativa ) was tested at measured concentra tions of 0 (control), 0.023, 0.049, 0.010, 0.20, 0.41 and 0.83 lb ai/A.-43 of 43- Biomass (dry weight), a preferred parameter, wa s not measured in the seedling emergence test. Of the parameters reported, shoot length was the most sensitive for all species. Lettuce was the most sensitive dicot with an EC 25 of 0.084 lbs ai/A. Due to the lo w number of replicates (three) and high degree of variability, the power of the study was insu fficient to determine a valid NOAEC; therefore, the EC 05 , 0.026 lbs ai/A, will be used for listed species assessment. Ryegrass was the most sensitive monocot, with an EC 25 of 0.17 lbs ai/A and a NOAEC of 0.099 lbs ai/A.

For vegetative vigor corn was tested at a singl e rate of 6.6 lbs ai/A, cabbage and tomato were tested at measured concentrations of 0 (control), 0.19, 0.38, 0.78, 1.5 and 3.0 lbs ai/A, cucumber was tested at 0 (control), 0.20, 0.41, 0.82, 1.7 and 3.3 lbs ai/A, lettuce was tested at was tested at 0 (control), 0.044, 0.097, 0.20, 0.41 and 0.82 lbs ai/A. Oat, soybean and ryegrass were tested at measured concentrations of 0 (control), 0.38, 0.78 , 1.5, 3.0, and 6.2 lbs ai/A. Onion was tested at measured concentrations of 0 (control), 0.41, 0.82, 1.7, 3.3 and 6.6 lbs ai/A, and radish was tested at measured concentrations of 0 (control), 0.097, 0.20, 0.41, 0.82 and 1.7 lbs ai/A. Effects were observed at all concentrations for several species, but the data were inadequate to calculate endpoints. Lettuce was the most sensitive dicot with an EC 25 of 0.085 and a NOAEC of 0.044 lbs ai/A.

Though supplemental data are available from the study, a continuation study (MRID 43844601; Supplemental) was conducted to clarify the endp oints for purposes of risk assessment. The continuation study was conducted on corn, onion ca bbage and cucumber and definitive endpoints determined, except for an onion NOAEC. This study confirmed that lettuce was the most sensitive dicot as determined in the previous study. Onion was determined to be the most sensitive monocot with an EC 25 of 0.27 lbs ai/A based on shoot weight. When a statistically determined NOAEC is greater than the calculated EC 25 , as is the case with onion in this study, the EC 05 is used for listed species assessment. The EC 05 for onion shoot weight is 0.042 lbs ai/A.