Page 2 of 15 

 The 2002 risk assessment addressed exposures and risks associated with the dietary, 

drinking water, and residential uses of asulam only. Based on the analysis conducted for the 

TRED, acute and chronic dietary and drinking water exposures for asulam do not present risks of 

concern. The residential exposure assessment conducted for the 2002 TRED determined that 

residential exposure are unlikely to occur based on label restrictions and product cost. 

Occupational exposures were addressed in an exposure assessment conducted for the 1995 RED. 

The occupational exposure assessment indicated that worker risks were not of concern. 

HED’s problem formulation conclusions are as follows. 1) The dietary exposure 

assessment is adequate based on current methodologies. 2) An updated drinking water 

assessment using current modeling methods is required. 3) The residential exposure assessment 

should be updated to reflect current standard operating procedures. 4) An updated occupational 

exposure assessment is needed. 5) The aggregate risk assessment needs to be updated based on 

current methodologies. 6) Studies required under 40 CFR Part 158 as a part of the new data 

requirements for registration of a pesticide (food and non-food uses) include an immunotoxicity 

study and acute and subchronic neurotoxicity studies. 

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Hazard Identification/Toxicology 

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

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

rat and dog demonstrate that the thyroid gland is a target organ for asulam. A two-year 

combined chronic/oncogenicity feeding study in rats showed hyperplastic changes in thyroid 

follicular cells. Subchronic studies in dogs showed increased absolute and relative thyroid 

weights in both sexes. Other toxicological effects included adrenal medullary hyperplastic 

alterations in male rats, and decreased body weight gains in male and female rats. 

Developmental toxicity studies in the rat and the rabbit are available for asulam. There 

was no indication of treatment-related effects on developmental parameters in the rabbit 

developmental toxicity study. Developmental effects were seen in the rat study but only at 

maternally toxic doses. A two-generation reproduction study in the rat showed treatment related 

decrease in mean live births per litter in the first generation providing evidence for a quantitative 

increased susceptibility of the rat fetus relative to adults. Parental systemic toxicity included 

decreased body weights and organ weight effects (increased absolute and relative thyroid and 

liver weights). A comparative thyroid rat assay in adults and offspring was required based on 

increased thyroid weights observed in rats, mice and dogs following subchronic and chronic 

exposures, hyperplastic changes in the thyroid follicular cells and thyroid gland C-cell 

carcinomas in male rats, and because none of the available toxicity studies examined potential 

changes in thyroid hormone levels. In addition, 21-day dermal and 28 day inhalation studies in rats 

with examination of thyroid weight and pathology were required. Asulam is classified as Group C, 

possible human carcinogen, based on thyroid and adrenal tumors in the rat study. HED 

determined that a low dose linear extrapolation risk model was not appropriate and that a 

quantitative cancer risk assessment was not required. 

 For the 2002 TRED, toxicity endpoints or points of departure (PODs) were selected for 

oral (dietary and drinking water), dermal and inhalation exposure to asulam. No acute dietary 

toxicity endpoint was identified because no adverse effect attributable to a single dose of asulam 

was observed. A chronic reference dose (cRfD) was established based on a chronic toxicity 

study in rats. An incidental oral endpoint was selected for potential residential exposure. 

Dermal and inhalation endpoints for worker exposure and potential residential handler exposure 

were identified in the TRED assessment. Although dermal and inhalation toxicity studies were 

available, these studies did not include an examination of the thyroid gland, the target organ for 

asulam. Therefore, oral endpoints were selected to assess potential effects from dermal and 

inhalation exposure. Because quantitative increased susceptibility in offspring/fetuses was seen 

in the rat reproduction study the FQPA factor of 10X was retained. No endpoints of concern 

regarding dermal toxicity, inhalation toxicity or other adverse effects were identified for the 

occupational exposure assessment conducted for the 1995 RED. 

Data Requirements

 The requirements for dermal, inhalation and comparative thyroid studies have been 

waived based on a reevaluation of thyroid effects (TXR 0052827, J. Liccione, 1/7/05). Acute 

and subchronic neurotoxicity studies are required to fulfill revised 40 CFR Part 158 Toxicology 
Page 5 of 15 

Data Requirements under 870.6200. An immunotoxicity study is required as a part of new data 

requirements in the 40 CFR Part 158 for conventional pesticide registration. Because the 

immune system is highly complex, studies not specifically conducted to assess immunotoxic 

endpoints are inadequate to characterize a pesticide’s potential immunotoxicity. While data 

from hematology, lymphoid organ weights, and histopathology in routine chronic or subchronic 

toxicity studies may offer useful information on potential immunotoxic effects, these endpoints 

alone are insufficient to predict immunotoxicity. Once all of the newly required toxicity data 

have been received and reviewed, the Asulam Registration Review Team recommends that the 

points of departure and safety factors be reexamined and a new risk assessment conducted, if 

necessary. 

Conclusions

The HED Registration Review problem formulation team has re-evaluated the toxicity 

analysis conducted for the 1995 and 2002 asulam risk assessments based on current Agency 

policies. Based on this evaluation, the toxicity data base is substantially complete. PODs for 

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

inhalation and PODs for the worker exposure assessment need to be revised and updated 

consistent with the endpoints identified for the TRED assessment. However, given the previous 

waiver of requirements for new dermal and inhalation toxicity studies based on a reassessment of 

thyroid effects, dermal and inhalation PODs for worker and/or residential handler exposure 

identified for the TRED need to be reevaluated to include available route specific studies as 

appropriate. In addition, the FQPA safety factor should be reevaluated based on current policy. 

Acute neurotoxicity, subchronic neurotoxicity and immunotoxicity studies are required under the 

updated 40 CFR Part 158 requirements (Appendix B). 

Dietary and Drinking Water Exposure 

The residues of concern in plants, livestock and drinking water are free and conjugated 

asulam, sulfanilamide, N4-acetylasulam, and N4-acetylsulfanilamide determined as a common 

moiety. A dietary exposure analysis for food only was conducted for the 2002 TRED using the 

Dietary Exposure Evaluation Model DEEM-FCIDTM. An acute dietary risk assessment was not 

performed since there was no acute endpoint identified by HIARC. A refined chronic dietary 

analysis was conducted for asulam using anticipated residues (ARs) based on field trial data and 

percent crop treated information. Chronic dietary risks showed no risks of concern for the 

general U.S. population and all population subgroups. The chronic dietary risk estimate for 

children 1-6 years (the highest exposed population subgroup) was 1% of the chronic population 

adjusted dose (PAD). The chronic dietary risks for all other populations was <1% of the acute 

and chronic population adjusted doses (PADs). 

 The Environmental Fate and Effects Division (EFED) performed a Tier I drinking 

water assessment to determine estimated environmental concentrations (EECs) for asulam in 

surface water and groundwater. Chronic drinking water levels of concern (DWLOCs) were 

calculated based on dietary exposure and water consumption estimates and default body 

weights. For the aggregate food and water exposure assessment, levels of concern for asulam in 

drinking water were compared with EECs of asulam in ground water and surface water. Based 
Page 6 of 15 

on this analysis, EECs for surface water and groundwater were not of concern (i.e., EECs were 

below the acute and chronic DWLOCs) 

Data Requirements

The data base for the dietary and drinking water assessment is complete. No additional 

data are required. The following product chemistry data were required in the TRED for technical 

asulam sodium salt: GLN 830.6317 (Storage Stability) and 830.6320 (Corrosion Characteristics). 

These data have been have been submitted and are under review. 

Conclusions

The dietary and drinking water exposure assessments need to be updated to reflect 

current methodologies for assessing combined dietary and drinking water exposures. 

Additionally, drinking water EECs were derived using older versions of the surface and ground 

water modeling programs. Therefore, a drinking water assessment using the Agency's most 

current modeling is needed to estimate drinking water concentrations for asulam. 

Tolerances and International Harmonization 

 There are no proposed or established Codex MRLs for residues of asulam in/on food/feed 

items; therefore, there are no compatibility questions with respect to U.S. tolerances and Codex 

MRLs. The tolerance expression for asulam needs to be reviewed and updated as necessary 

based on HED’s Interim Guidance on Tolerance Expressions (S. Knizner, 5/27/09). A summary 

of US and international tolerances and maximum residue limits is provided in Appendix C. 

Residential Exposure 

 A qualitative review of residential exposure conducted for the 2002 TRED concluded that 

a quantitative residential exposure assessment was not required since there were no registered 

residential uses and potential residential exposures were not anticipated as a result of 

applications of asulam. Quantitative residential exposure assessments were not conducted for 

either the 1995 RED or the 2002 TRED. 

Conclusions

The qualitative residential exposure review needs to be reevaluated based on current 

standard operating procedures. Based on current standards, a quantitative residential exposure 

assessment may be required (i.e., an assessment of residential exposures associated with use of 

asulam on non-cropland areas may be needed). 

Aggregate Exposure 

The aggregate risk assessment integrated dietary and drinking water exposure 

assessments. For the TRED, the long term aggregate risk was assessed by adding exposure 

estimates from dietary and drinking water pathways, calculating a DWLOC based on the 
Page 7 of 15 

aggregate exposure estimate and comparing the DWLOC with model based EECs determined by 

EFED. Model-based estimates for allowable concentrations in surface water and groundwater 

were less than the short-term DWLOCs indicating that aggregate exposure to asulam via food, 

water exposure is less than HED’s level of concern. 

Conclusions

The aggregate exposure assessment for chronic food and water exposure needs to be 

updated to reflect current standard operating procedures (SOPs). Additionally, if a quantitative 

residential exposure assessment is required based on current SOPs, a short term aggregate 

assessment which combines food, water and residential exposures will also be needed. 

Occupational Exposure 

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

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

that a quantitative occupational exposure assessment was not required because the toxicology 

criteria for a quantitative assessment were not triggered and no endpoints of concern regarding 

dermal toxicity, inhalation toxicity or other adverse effects were identified. Dermal and 

inhalation endpoints for worker exposure were identified for the TRED. However, because the 

risk assessment was conducted to support a TRED only, no occupational exposure and risk 

assessments were conducted for the assessment conducted in 2002. 

Conclusions

An updated occupational risk assessment is needed for the Registration Review of asulam 

in light of significant changes to standard exposure protocols, assumptions and algorithms and to 

incorporate updated dermal and inhalation PODs. 

Incident Report 

An updated incident report was recently conducted. Based on the low frequency and 

severity of incident cases, there does not appear to be a concern at this time that would warrant 

further investigation. The Agency will continue to monitor the incident information and if a 

concern is triggered, additional analysis will be included in the risk assessment. 

Endocrine Disruption

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

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

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

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

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

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

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

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 
Page 8 of 15 

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

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

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

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

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

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

ingredients. This list of chemicals was selected based on the potential for human exposure 

through pathways such as food and water, residential activity, and certain post-application 

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

disruptors. 

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 Agency 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 EDSP, the policies and procedures, the list of 

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

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

Cumulative 

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

common mechanism of toxicity with other substances. EPA has not made a common mechanism 

of toxicity finding for asulam and any other substances and, asulam does not appear to produce a 

toxic metabolite produced by other substances which have tolerances in the U. S. Therefore, 

EPA has not assumed that asulam has a common mechanism of toxicity with other substances. 

Human Studies 

No human studies were used in past risk assessments conducted for asulam. However, 

any future occupational and/or residential assessments conducted for asulam will be based on 

data contained in HEDs generic pesticide exposure databases such as the Pesticide Handlers 

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

Outdoor Residential Exposure Task Force (ORETF) Database. EPA has reviewed all the studies 

supporting these multi-pesticide generic exposure databases, and has found no clear and 

convincing evidence that the conduct of any of them was either fundamentally unethical or 

significantly deficient relative to the ethical standards prevailing at the time the research was 

conducted. All applicable requirements of EPA’s Rule for the Protection of Human Subjects of 

Research (40 CFR Part 26) have been satisfied, and there is no regulatory barrier to continued 

reliance on these studies. 
Page 9 of 15 

Environmental Justice 

Potential areas of environmental justice concerns, to the extent possible, were considered 

in this human health risk assessment, in accordance with U.S. Executive Order 12898, "Federal 

Actions to Address Environmental Justice in Minority Populations and Low-Income 

Populations," http://www.eh.doe.gov/oepa/guidance/justice/eo12898.pdf). 

As a part of every pesticide risk assessment, OPP considers a large variety of consumer 

subgroups according to well-established procedures. In line with OPP policy, HED estimates 

risks to population subgroups from pesticide exposures that are based on patterns of that 

subgroup’s food and water consumption, and activities in and around the home that involve 

pesticide use in a residential setting. Whenever appropriate, non-dietary exposures based on 

home use of pesticide products and associated risks for adult applicators and for toddlers, youths, 

and adults entering or playing on treated areas postapplication are evaluated. Further 

considerations are currently in development, as OPP has committed resources and expertise to 

the development of specialized software and models that consider exposure to bystanders and 

farm workers as well as lifestyle and traditional dietary patterns among specific subgroups. 

Conclusions/Future Actions Needed 

The actions needed in the future Registration Review for asulam are listed below. 

Hazard Identification and Endpoint Selection

The existing hazard identification and endpoint selection assessment for the occupational 

exposure assessment needs to be revised to reflect the PODs identified in the TRED and the fact 

that requirements for new route specific inhalation and dermal studies have been waived. The 

FQPA safety factor needs to be reevaluated based on current OPP policy. Acute neurotoxicity, 

subchronic neurotoxicity and immunotoxicity studies are required in accordance with the revised 

40 CFR Part 158 Toxicology Data Requirements. 

Dietary Exposure and Risk

The dietary and drinking water exposure assessments need to be updated to reflect current 

methodologies for assessing combined dietary and drinking water exposures. An updated 

drinking water assessment using the Agency's most current modeling is needed to estimate 

drinking water concentrations for asulam. 

Residential Exposure and Risk

The residential risk assessment should be updated to reflect current policies and SOPs. 

Aggregate Exposure and Risk

The existing aggregate exposure assessment needs to be updated to reflect current SOPs. In 

addition, if a quantitative residential exposure assessment is required, a short term aggregate 

assessment which combines food, water and residential exposures will also be needed. 
Page 10 of 15 

Occupational Exposure and Risk

The existing occupational exposure assessment needs to be reevaluated and revised based on an 

updated toxicity assessment and current refined exposure assumptions and algorithms. 

Incident Report

Based on the incident report, there does not appear to be a concern at this time. The Agency will 

continue to monitor the incident information and if a concern is triggered, additional analysis 

will be included in the risk assessment. 

Data Requirements 

- Acute Neurotoxicity (GLN 870. 6200a) 

- Subchronic Neurotoxicity (GLN 870.6200b) 

- Immunotoxicity study (GLN (870.7800) 
Page 11 of 15 

References 

Asulam. HED Human Health Assessment for the Tolerance Reassessment Eligibility Decision J. 

Morales (2/28/02, D276505) 

Asulam – Report of the FQPA Safety Factor Committee C. Christensen (2/5/02, TXR No. 

0050454) 

Asulam – 2nd Report of the Hazard Identification Review Committee J Liccione (12/6/01 TXR 

No. 0050324) 

Asulam – Tolerance Reassessment Eligibility Decision Document. Product and Residue 

Chemistry Chapter J. Morales (12/6/01 D2778884) 

Conclusions of the HED Metabolism Assessment Review Committee on Asulam and Degradates 

of Concern in Water for TRED C. Eiden (1/23/02, D280438) 

Occupational and Residential Exposure Assessment and Recommendations for the Asulam 

Reregistration Eligibility Document (RED), J. Evans (3/30/94, D187156) 

Asulam. Chronic Dietary Exposure Assessment for the Tolerance Reassessment Eligibility 

Decision J. Morales (12/18/01, D279592) 

Asulam and Sodium Asulam: Review of Human Incidents. S. Recore (11/30/10, D383616) 

WA080001; Asulox Herbicide on Spinach Grown for Seed in Washington State. Special Local 

Needs Registration – Section 24c W. Wassell (4/22/08, D389977) 

Asulam: Data Call-In Waiver Requests J. Liccione (1/7/05, TXR No. 0052827) 

 
Page 12 of 15 

Appendix A 

Summary of Toxicity Endpoints and Doses for Asulam Risk Assessment 

EXPOSURE 

SCENARIO 

DOSE 

(mg/kg/day) 

ENDPOINT STUDY 

Acute Dietary 

An appropriate endpoint attributable to a single dose was not identified. 

Acute RfD = not established 

Chronic Dietary NOAEL = 36 mg/kg/day 

UF = 100 

FQPA Safety Factor = 10 

The LOAEL was 180 mg/kg/day based on 

hyperplastic changes in the adrenal 

medulla and in thyroid follicular cells of 

males. 

Combined 

Chronic 

Toxicity/Oncog

enicity in the rat 

Chronic RfD = 0.36 mg/kg/day

Chronic PAD = 0.036 mg/kg/day

Incidental Oral, ShortTerm 

A toxicity endpoint was not selected because there are no residential uses. 

Incidental Oral, 

Intermediate-Term 

A toxicity endpoint was not selected because there are no residential uses. 

Dermal, Short-Term Oral NOAELa = 50 mg/kg/day The LOAEL was 250 mg/kg/day based on 

significant decreases in mean live births 

per litter. 

Two Generation 

Reproduction 

Study in the rat 

 Dermal, IntermediateTerm 

Oral NOAELa

 = 50 mg/kg/day The LOAEL was 250 mg/kg/day based on 

significant decreases in mean live births 

per litter. 

Two Generation 

Reproduction 

Study in the rat 

Dermal, Long-Term Oral NOAELa

 = 36 mg/kg/day The LOAEL was 180 mg/kg/day based on 

hyperplastic changes in the adrenal 

medulla and in thyroid follicular cells of 

males. 

Combined 

Chronic 

Toxicity/Oncog

enicity in the rat 

Inhalation, ShortTerm 

Oral NOAELb

 = 50 mg/kg/day The LOAEL was 250 mg/kg/day based on 

significant decreases in mean live births 

per litter. 

Two Generation 

Reproduction 

Study in the rat 

 Inhalation, 

Intermediate-Term 

Oral NOAELb

 = 50 mg/kg/day The LOAEL was 250 mg/kg/day based on 

significant decreases in mean live births 

per litter. 

Two Generation 

Reproduction 

Study in the rat 

Inhalation, Long-Term Oral NOAELb = 36 mg/kg/day The LOAEL was 180 mg/kg/day based on 

hyperplastic changes in the adrenal 

medulla and in thyroid follicular cells of 

males. 

Combined 

Chronic 

Toxicity/Oncog

enicity in the rat

 
Page 13 of 15 

Appendix B 

Guideline Number: 870.6200 

Study Title: Neurotoxicity Battery (Acute and Subchronic Studies)

Rationale for Requiring the Data 

This is a new data requirement under 40 CFR Part 158 as a part of the data requirements for 

registration of a pesticide (food and non-food uses). 

The Neurotoxicity Screening Battery (OPPTS 870.6200) is designed to evaluate the potential 

adverse effects on the nervous system from exposure to pesticide chemicals. The Agency believes 

that the guideline studies are inadequate in their assessment of behavioral effects and do not use 

optimal methods to evaluate the potential toxicity to the nervous tissue structure and function. To 

detect and characterize these potential effects more fully, a battery of more sensitive testing is 

required. The objective of this neurotoxicity battery testing is to evaluate the incidence and 

severity of the functional and/or behavioral effects, the level of motor activity, and the 

histopathology of the nervous system. The acute neurotoxicity study is required to detect possible 

effects resulting from a single exposure. The subchronic neurotoxicity study is intended to detect 

possible effects resulting from repeated or long-term exposures. 

Practical Utility of the Data 

How will the data be used? 

The acute and subchronic neurotoxicity studies provide critical scientific information needed to 

characterize potential hazard to the human population on the nervous system from pesticide 

exposure. These studies can provide data on a wide range of functional tests for evaluating 

neurotoxicity including sensory effects, neuromuscular effects, learning and memory and 

histopathology of the nervous system. For example, animal studies with organophosphorous 

chemicals have shown neurotoxicity to be the primary toxic endpoints (e.g., cholinesterase 

inhibition) of concern in rodents and non-rodents. These animal studies can be used to select 

endpoints and doses for use in risk assessment of all exposure scenarios and are considered a 

primary data source for reliable reference dose calculation. The Agency has established an oral 

reference dose (RfD) for assessing dietary risks for a number of chemicals (e.g., organophoshates 

and carbamates) where neurotoxicity was the most sensitive endpoint of concern. 

How could the data impact the Agency's future decision-making? 

If the acute or subchronic neurotoxicity studies show that asulam poses either a greater or a 

diminished risk than that given in the interim decision’s conclusion, the risk assessment for asulam 

may need to be revised to reflect the magnitude of potential risk derived from the new data. 

 

If the Agency does not have this data, a 10X database uncertainty factor may be applied when 

conducting a risk assessment using the currently available studies.
Page 14 of 15 

Guideline Number: 870.7800 

Study Title: Immunotoxicity

Rationale for Requiring the Data 

This is a new data requirement under 40 CFR Part 158 as a part of the data requirements for 

registration of a pesticide (food and non-food uses). 

The Immunotoxicity Test Guideline (OPPTS 870.7800) prescribes functional immunotoxicity 

testing and is designed to evaluate the potential of a repeated chemical exposure to produce 

adverse effects (i.e., suppression) on the immune system. Immunosuppression is a deficit in the 

ability of the immune system to respond to a challenge of bacterial or viral infections such as 

tuberculosis (TB), Severe Acquired Respiratory Syndrome (SARS), or neoplasia. Because the 

immune system is highly complex, studies not specifically conducted to assess immunotoxic 

endpoints are inadequate to characterize a pesticide’s potential immunotoxicity. While data from 

hematology, lymphoid organ weights, and histopathology in routine chronic or subchronic 

toxicity studies may offer useful information on potential immunotoxic effects, these endpoints 

alone are insufficient to predict immunotoxicity. 

Practical Utility of the Data 

How will the data be used? 

Immunotoxicity studies provide critical scientific information needed to characterize potential 

hazard to the human population on the immune system from pesticide exposure. Since 

epidemiologic data on the effects of chemical exposures on immune parameters are limited and 

are inadequate to characterize a pesticide’s potential immunotoxicity in humans, animal studies 

are used as the most sensitive endpoint for risk assessment. These animal studies can be used to 

select endpoints and doses for use in risk assessment of all exposure scenarios and are considered 

a primary data source for reliable reference dose calculation. For example, animal studies have 

demonstrated that immunotoxicity in rodents is one of the more sensitive manifestations of 

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) among developmental, reproductive, and 

endocrinologic toxicities. Additionally, the EPA has established an oral reference dose (RfD) for 

tributyltin oxide (TBTO) based on observed immunotoxicity in animal studies (IRIS, 1997). 

How could the data impact the Agency's future decision-making? 

If the immunotoxicity study shows that the test material poses either a greater or a diminished 

risk than that given in the interim decision’s conclusion, the risk assessments for the test material 

may need to be revised to reflect the magnitude of potential risk derived from the new data. 

 

If the Agency does not have this data, a 10X database uncertainty factor may be applied for 

conducting a risk assessment from the available studies.

 

 
Page 15 of 15 

Appendix C 

International Residue Limits 

Asulum/Sodium asulam (106901/106902; 11-16-2010) 

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition: 

US Canada Mexico2 Codex3 

40 CFR 180.360:

Plant/Livestock: combined residues of 

asulam (methyl sulfanilylcarbamate) 

and its sulfanilamide containing 

metabolites

None None

Commodity1 Tolerance (ppm) /Maximum Residue Limit (mg/kg) 

US Canada Mexico2 Codex 

Cattle, fat 0.05 

Cattle, meat 0.05 

Cattle, meat byproducts 0.2 

Goat, fat 0.05 

Goat, meat 0.05 

Goat, meat byproducts 0.2 

Hog, fat 0.05 

Hog, meat 0.05 

Hog, meat byproducts 0.2 

Horse, fat 0.05 

Horse, meat 0.05 

Horse, meat byproducts 0.2 

Milk 0.05 

Sheep, fat 0.05 

Sheep, meat 0.05 

Sheep, meat byproducts 0.2 

Sugarcane, cane 1.0 

Sugarcane, molasses 30 

 

Completed: M. Negussie; 11/17/2010 

1

 Includes only commodities of interest for this action. Tolerance values should be the HED recommendations and 

not those proposed by the applicant. 

2 Mexico adopts US tolerances and/or Codex MRLs for its export purposes. 

3 * = absent at the limit of quantitation; Po = postharvest treatment, such as treatment of stored grains. PoP = 

processed postharvest treated commodity, such as processing of treated stored wheat. (fat) = to be measured on the 

fat portion of the sample. MRLs indicated as proposed have not been finalized by the CCPR and the CAC.