# Tolerance Re assessment Eligibility Decision for Urea Sulfate

June 200 5

### Tolerance Reassessm ent Eligibility Decision

Urea Sulfate

Special Review and Reregistration Division Office of Pesticide Program s U.S. Environm ental Protection Agency 1801 South Bell Street Arlington, VA 22202

June 14, 2005

### Background: The Federal Insecticide, Fungicide, and Rodenticid e Act (FIFRA) was am ended in 1988 to accelerate the reregistration of products with active ingredients regi stered prior to Novem b er 1, 1984. The am ended Act called for the developm ent and subm i ssion of data to support the reregistration of an active ingredient, as well as a review of all subm itted data by the U.S. Environm ental Protection Agency (referred to as EPA or the Agency ) to assess the currenttolerances. Reregistration involves a thorough review of the scientific database underly i ng a pesticide’s registrati on. The purpose of the Agency ’s review is to reassess the potential hazards arising from the currently re gistered uses of the pes ticide; to determ ine the need for additional data on health and environm enta l effects; and, to determ ine whether or not the pesticide m eets the “no unreasonable adverse effects” criteria of FIFRA. On August 3, 1996, the Food Quality Protection Act (F QPA) was signed into law. FQPA am ends FIFRA to require tolerance reassessm ent during reregistration. In addition, FQPA requires that all active ingredients first registered after 1984 would also bereevaluated to reassess their current tolerances, by 2006. FQPA also am ends the Federal Food, Drug, a nd Cosm etic Act (FFDCA) to require a safety finding in tolerance reassessm ent based on factors including an assessm ent of cumu lative effects of chem icals with a com m on m echanism of toxicity

. In this docum ent, the current exemption from the re quirem e nt for a tolerance for urea sulfate is being reassessed in order to m eet FQPA standards. Th is docum ent represents the Lower Risk Pesticide Chem ical Focus Group’s (LRPCFG) Tolerance Reassessm ent Eligibility Decision (TRED) on urea sulfate (m onocarbam i de dihy drogen sulfate). Urea sulfate is used both as an herbicide and desiccant (each current label actually lists this active ingredient as 1-am inom ethanam i de dihy drogen tetraoxosulfate). This active ingredient was first registered in 1987. The Agency has determ ined that urea sulfate readily degrades to urea and sulfuric acid and/or sulfate ions in the environm ent and in the hum an body

. Ther efore, this tolerance reassessm ent for the active ingredient urea sulfate is based on the recent tole rance reassessm ents perform ed on both urea and sulfuric acid and its salts. Urea tolerances were reassessed under the 2002 TRED for urea, while the active and inert tolerances for sulfuric acid were reassessed th rough the LRPCFG’s assessm ent of m i neral acids and their am m onium , calcium , ferrous, ferric, m a gnesium , potassium , sodium , and/or zinc salts (7/24/2002). In addition, the Mineral Acids TRED relied on in form ation from the 1993 Mineral Acids Reregistration Eligibility Decision (RED). 

### I. Executive Summary : Urea sulfate is used prim arily as an active ingredient in herbicides and desiccants on agricultural crops. Five products are currently registered with urea sulf ate as an active ingredient, three of which contain urea sulfate as the only active ingredient. According to an EPA Pesticide Fact Sheet, “Acute toxicology data indicate that the chem ical is extrem ely caustic and corrosive. The appropriate toxicity category is I (DANGER), based on prim ary ey e and skin irritation studi es. Chronic toxicology and environm ental fate data requirem e nts are waived.” Since urea sulfate read ily degrades to urea and sulfuric acid and/or sulfate ions in the environm ent and in the hum an body , the Agency used the toleran ce reassessm ents for urea and sulfuric acid (sulfate salts) to r eassess the tolerance for urea sulfate. The urea TRED states that “Based on the hazar d assessm ent of urea, exposures to this compound resulting from reasonably anticipated patterns of u sage present a reasonable certainty of no harm to
1hum an health. Given the low toxicity of urea, a m o re detailed assessm ent of risks resulting from exposure to urea, when used either as a frost protectant or pesticide inert ingredient, is not necessary based on the hazard assessm ent of urea, exposures to this compound resulting from reasonably anticipated patterns of usage were not believed to present a reasonable certainty of harm to hum an health.” According to the Mineral Acids RED, sulfuric acid h as registered food uses. However, because sulfuric acid rapidly degrades in the environm ent to sulfate i ons, which are of no toxicological concern, sulfuric acid has been granted an exemption from tolerance requirem e nts. While it was determ ined that the use of sulfuric acid as a potato vine desiccant m i ght result in derm al and inhalation exposure to workers, all other uses of pesticide products containing sulfuric acid were determ ined to not pose unreasonable risks or adverse effects to hum ans or the environm ent. According to LRPCFG’s TRED for Mineral Acids and their Salts, when exposed to liquids, the salts of su lfuric acid would dissociate to the respective m e tal cation and the sulfate anion. That TRED reported th at there was not any available inform ation for the sulfate ion or any of the salts of sulfuric acid that would indicate a hum an health hazard to the general public or any population subgroup resulting from either the EPA-regulated uses or the FDA GRAS uses, and that no additional inform ation was needed to assess th e safety of the sulfuric acid or any of its salts. Based on the findings in the TREDs for both urea and sulf uric acid (sulfate salts), and the dissociation of urea sulfate to each of these resulting products, it has b een determ ined that the use of products containing only urea sulfate as the active ingredient would not pr esent a hum an health hazard to the general public. Products containing urea sulfate in addition to othe r active ingredients (ethephon and gly phosate or any other m i xed active ingredient products which mi ght beco m e registered in the future) would need to be assessed as part of those respective REDs and/or TREDs for those active ingredients, but it is determined in this TRED that urea sulfate alone m a y be r eassessed as not presenting an unreasonable risk to hum ans or the environm ent. Furtherm ore, the current ex emption from the requirem e nt of a tolerance for urea sulfate has been reassessed and m eets the reasonable certainty of no harm as defined by FQPA. 

### II. Use Information : Urea Sulfate Urea sulfate (CAS Num b er 21351-39-3) has several sy nony m s : 1-am inom ethanam i de dihy drogen tetraoxosulfate (the nam e listed as the active ingr edient on all the current labels); m onocarbam i de dihy drogen sulfate; Enquik; N-TAC Desiccant; sulf uric acid m onourea; sulfuric acid, m onourea adduct; urea sulfuric acid m onoadduct; and urea sulfate (1:1). As m e ntioned above, urea sulfate is used prim arily as an active ingredient in herbicides and desiccants on agricultural crops (PC Code 128961). The first urea sulfate product was registered in 1987. The so le registrant listed in OPPIN Query is Entek Corporation. Recently , Griffin LLC purchased Entek, and DuPont Crop Protection is a prim ary owner of Griffin, so DuPont is now considered to be the registrant for the urea sulfate products. Five products are currently registered with urea sulf ate as an active ingredient, 3 of which contain urea sulfate as the only active ingredient (See Table 1). E ach of the current products is formulated as soluble concentrates, except for one, Enquik MP (68891-6), wh ich is a Manufacturing Use product. All of the products with urea sulfate as the sole active ingredie nt are listed as containing 79% ai, although two other products also contain other active ingredients. In addition, there is currently one SLN (FL960011), while the OPP REFS lists 18 other SLNs, which have been cancelled, as well as 4 SLNs, which have been withdrawn.

2Table 1. Registered Products Being Reassessed Containing Urea Sulfate Registration

Num b er Registration Nam e Percent Urea Sulfate Other Active Ingredients Formulation Type Date first registered
68891-1 SuperQuikTM 79 None soluble concentrate 30 Dec, 1987
68891-4 W ilThin Blossom Thinner 79 None soluble concentrate 12 Jan, 1995

68891-6 Enquik MP 79 None formulation interm ediate 2 Feb, 1996
68891-7 ETK-2201 58.6 18.3% ethephon soluble concentrate 1 Feb, 1996
68891-8 ETK-2301 Herbicide 71.1 9.6% glyphosate soluble concentrate 18 Dec, 1996
FL960011 Enquik 79 None soluble concentrate 22 Oct, 1992 The BEAD Screening Level Usage Analy s is (SLUA) in Appendix A indicates that m o st of the urea sulfate is applied to cotton, that is, the ETK -2201 product (also know as CottonQuik), a product also containing ethephon. DuPont has subm itted confidentia l sales data to the Agency indicating that their records, as well as those of Entek, indicate thatETK-2201 is the only product which has any sales over the last few y ears. The tolerance exemption being reassessed in this docum en t, with the respective citation in the Code of Federal Regulations (CFR), and the use pattern as an ac tive ingredient are listed in Table 2. Specifically , the tolerance expression at 40 CFR 180.1084 is stated as follows: “m onocarbam i de dihy drogen sulfate is exempted from the requirem e nt of a tolerance when used as an herbicide or desiccant in or on all raw agricultural com m odities.” Table 2. Exemption from the Requirement for a Tolerance Being Reassessed for Urea Sulfate Tolerance Exem ption Expression CAS No. 40 CFR PC Code Use Pattern Active Ingredient “m onocarbami de dihydrogen sulfate” 21351-39-3 180.1084 128961 as an herbicide or desiccant
Urea Urea was registered by EPA in 1995 for use as a frostprotectant pesticide under the trade nam e Enfrost. Enfrost is a 43% liquid formulation of urea that m a y be applied com m e rcially to a wide variety of field crops, vegetables, fruit trees and ornam e ntals to reduce frost dam a ge. There are currently no residential uses for urea as a pesticide product. Enfrost is the only currently registered pesticide product containing urea as an active ingredient, but Enfrost has not been actively produced or sold by the registrant, Entek Corporation, since 1995. However, according to th e Urea TRED (EPA, 2002a), the registrant m a intains active registration of Enfrost for potential future production and use. In addition, urea is used as an iner t pesticide ingredient as a stabilizer, inhibitor, or intensifier. Also,

3several m illion tons of urea are produced annually for u se in fertilizer and as an anim al feed supplem ent, with som e of the urea being added as a fertilizer in pesticidal products. Moreover, urea is used in the m a nufacture of dy es, fire retardant paints, plastic izers, and stabilizers for explosives (EPA, 2002a). The tolerance exemptions reassessed for urea, with the respective citation in the Code of Federal Regulations (CFR), and the use pattern as an activ e and inert ingredient are listed in Table 3. Table 3. Exemption from the Requirement fo r a Tolerance Reassessed in the 2002 Urea TRED

Tolerance Exem ption Expression CAS No. 40 CFR PC Code Use Pattern

urea 57-13-6 Active Ingredient 180.1117 085702 frost protectant Inert Ingredient 180.1001 (c), (d), (e) 885702 stabilizer, inhibitor, or intensifier Sulfuric Acid and its Salts As an active ingredient in pesticides, sulfuric acid is used as a desiccant, and it is also used to kill bacteria on potatoes, in m ilking equipm ent, and within food processing areas. It was first registered as a desiccant/herbicide in the U.S. as early as 1971 and was exempted from the requirem e nt for a residue tolerance for this use (40 CFR 180.1019). A food processing sanitizer product, containing sulfuric acid as well as other active ingredients, was registered in 1992. Sulfuric acid as an active ingredient was evaluated in the 1993 Mineral Acids RED (EPA, 1993). In addition, sulfuric acid is registered for use as an inert ingredient in certain pesticide products. It is prim arily used as a pH control agent and is included at concentrations of up to 0.1% of the pesticide formulation, according to the Sulfuric Acid and its Salts TRED (EPA, 2002b). The tolerance exemption reassessed for su lfuric acid, with the respective citation in the Code of Federal Regulations (CFR), and the use pattern as an active ingredient are listed in Table 4.

Table 4. Exemption from the Requirement for a Tolerance Reassessed in the 2002 Mineral Acids (Sulfuric Acid) TRED Tolerance Exem ption Expression CAS No. 40 CFR PC Code Use Pattern

sulfuric acid 7664-93-9 Active Ingredient
180.1019 078001 used to kill bacteria on potatoes, milking equipm ent and in food processing areas; as a desiccant Inert Ingredient 180.1001(c) 878001 pH control agent

4III. Physical/Chemical Properties : The phy sical and chem ical properties of urea sulfate are provided in Table 5. This inform ation was obtained from the profiles in TOXNET (Chem I Dplus) and Camb ridgeSoft (ChemF inder), as well as various MSDS sheets for urea sulfate/m onocarbami de dihy drogen sulfate.
Table 5. Physical/Chemical Properties of Urea Sulfate References

Structure ChemIDplus Lite (2004)

Chemical Nam e urea sulfate; uronium hydrogen sulphate Molecular formula CH 4 N 2 O · H 2 SO 4

MSDS (2004) Color/Form Clear to slightly hazy liquid Odor odorless Boiling point Decom p oses (110 o C or 230 o F) Melting point 5.6 o C (42 o F) Salt out tem p . Density/Specific Gravity 12.65 lbs/gal; 1.52 (W ater =1) pH 1 (for a 10% solution in water) Solubilities Easily soluble in cold water, hot water Volatility 18% (w/w)

IV. Haz a rd Characteriz a tion : A. Toxicity Acute toxicity studies were conducted to support regi stration of urea sulfate. Table 6 provides the inform ation available on the acute toxicity of urea sulf ate. Currently , there are no chronic toxicity studies available for urea sulfate. According to an EPA Pesticide Fact Sheet (EPA, 1987), chronic toxicity studies were waived in accordance with provisions of 40 CFR 162.45 (c).

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### Table 6. Acute Toxicity Profile for Urea Sulfate (monocarbamide dihydrogen sulfate) Study Type Acute Oral Species Rat Results 1,200 m g /kg (m ale) 350 m g /kg (fem ale) Toxicity Category II Reference

EPA Pesticide

Fact Sheet

(1987) Acute Derm al Rabbit >2 g/kg Study terminated at 48 hrs because of extrem e caustic action and derm al necrosis. Not determined Acute Inhalation Rat >10.8 m g /L III Prim ary Eye

Irritation Rabbit Severe corneal involvem e nt, grade 4 chem osis of conjunctivae at 24 hrs. I
Prim ary Skin

Irritation Rabbit Caustic on intact and abraded skin at 24 hours. Study was terminated at 24 hours after similar results were obtained with 1:4 v/v dilution with water I
For urea, the acute toxicity studies were subm itted by the registrant. These acute studies indicated that the registered product for urea (i.e., the frost protectant) was a slight ey e irritant and had a low toxicity to anim als. In addition, there were other studies cite d from the available literature. In subchronic studies, no severe toxicity was observed for urea in dogs, and no adverse organ pathology was found. In addition, anim al studies provided no evidence of adverse chroni c or carcinogenic effects, nor developm ental or teratogenic effects. For sulfuric acid, the available toxicity studies indicate that is corrosive to the ey es and skin and is toxic via the inhalation route. However, sulfuric acid read ily degrades in the environm ent to sulfate ions. In addition, studies conducted with the salts of sulfuric acids indicate that these salts are not of toxicologic concern, especially since these salts dissociate in water into the resp ective m e tal cation and the sulfate anion. 

### B. Metabolism The Agency has determ ined that urea sulfate rapidly de grades to urea and sulfuric acid and/or sulfate ions in the hum an body

. Thus, the data requirem e nts for th e higher tier toxicity studies have all been waived by the Agency , and there are no repeated dose t oxicity studies available for urea sulfate. 

### C. Special Considerations for Infants and Children Data from repeated dosing toxicity studies with anim als does not exist for urea sulfate. However, urea sulfate readily degrades to urea and sulfuric acid and/or the sulfate ion in the body

. Based on the toxicity data reviewed in this tolerance assessm ent docum ents fo r urea and for sulfuric acid and its salts, there are no adverse effects that would be expected in infant s and children for urea sulfate. For urea, anim al studies provide no evidence of developm ental nor teratogenic effects. In an aqueous environm ent, sulfuric acid rapidly ionizes to sulfate ions which are of no toxicological concern to infants and children. For these reasons, a safety factor analy s is has not b een used to assess the risks resulting from the use of urea sulfate; therefore, an additional tenfold safety factor for the protection of infants and children is

6unnecessary . 

### V. Exposure Assessment : The Agency has determ ined that ur ea sulfate breaks down readily into both urea and sulfuric acid and/or sulfate ion in the hum an body

. Since the risks have already been assessed for these various other chem icals, it is not necessary to repeat these other risk assessm ents to reassess th e food-use tolerance for urea sulfate. The conclusions of the RED docum ents for urea and m i neral acids (sulfuric acid), as well as the TRED docum ents for urea and the m i neral acids (sulfuric acid and its salts), indicate that these chem icals have been determ ined to not present unacceptable risks to hum ans or the environm ent. 

### VI. Dietary Exposure : Based on the dissociation of urea sulfate in the hum an body to urea and sulfuric acid and/or sulfate ion, the Agency has determ ined that only a qualitative diet ary assessm ent is needed, basedon the results of the REDs and TREDs for these constituent products. Thus , the Agency has determ ined that there are no dietary risk concerns, whether from the ingestion of f ood or water or both, for urea sulfate (or at least for the consumption of products containing ur ea sulfate as the sole active ingredient). 

### VII. Aggregate Assessment : In exam ining aggregate exposure, FFDCA section 408 directs EPA to consider available inform ation concerning exposures from the pesticide residue in food and all other non- occupational exposures, including drinking water from ground water or surf ace water and exposure through pesticide use in gardens, lawns, or buildings (residential and othe r indoor uses). In developing this tolerance assessm ent docum ent for urea sulfate, a qualitative assessm ent for all pathway s of hum an exposure (food, drinking water, and residential) is appropriate given the lack of hum an health concerns associated with exposure to this chem ical, as well as its constituent products (urea and sulfuric acid and/or sulfate ions). 

### VIII. Cumulative Exposure : Section 408(b)(2)(D)(v) of the FFDCA requires that, wh en considering whether to establish, m odify , or revoke a tolerance, the Agency consider “available inform ation” concerning the cumu lative effects of a particular pesticide’ s residues and “other substan ces that have a com m on m echanism of toxicity .” If chem icals are structurally related and all are low toxi city chem icals, then the risks either separately or comb ined should also be low. EPA does not have, at this tim e, available datato determ ine whether urea sulfate has a com m on m echanism of toxicity with other substances. Unlike other pesticides for which EPA has followed a cumu lative risk approach based on a com m on m ech anism of toxicity , EPA has not m a de a com m on m echanism of toxicity finding as to urea sulfate and any other substances, and urea sulfate does not appear to produce a toxic m e tabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has assum e d that urea sulfate does not have a com m on m echanism of toxicity with other substances. For inform ation regarding the Agency ’ s efforts to determ ine which chem icals have a com m on m echanism of toxicity and to evaluate the cumu lative effects of such chem icals, see the policy statem ents released by EPA’ s Office of Pesticide Program s concerning com m on m echanism determ inations and procedures fo r cumu lating effects from substances found to have

7a com m on m echanism on EPA’s website at http://www.epa.gov/pesticides/cumu lative/. 

### IX. Risk Characteriz a tion : As m e ntioned above, the Agency has been determ ined that urea sulfate readily breaks down into urea and sulfuric acid and/or sulfate ion in the environm ent and in the hum an body

. Assessm ents perform ed on both these substituent compounds indicate no reasonable cer tainty of harm to hum an health from either the EPA-registered uses or the FDA-GRAS uses. Ther efore, it has been determ ined that the use of products containing urea sulfate (as the sole active ingredient) also would not present a hum an health hazard to the general public. 

### X. Environmental Fate/Ecotoxicity/Drinking Water Considerations : Urea Sulfate All of the environm ental fate data requirem e nts for urea sulfate have been waiv ed by the Agency because the environm ental fate is so well known for its tw o substituent compounds, urea and sulfuric acid. In addition, m a ny of the ecotoxicity data requirem e nts have also been waived. It has also been determ ined that the use of products containing urea sulfate is not expected to impact groundwater, according to a docum ent prepared by the New York State Departm e nt of Environm ental Conservation regarding the uses of various urea sulfate end-use products (EPA, 1997). Urea Available data from literature reviews show that ur ea degrades rapidly in m o st soils, with it generally hy droly zed to am m onium through soil urease activity

. In various soils, the hy droly s is m a y near comp letion within 24 hours; however, the rate of hy droly s is can be mu ch slower depending upon soil ty pe, m o isture content, and urea formulation. Soil ad sorption studies show that urea sorbs very weakly to soil; therefore, leaching is possible. Ultim ate degradation of urea produces am m onia and carbon dioxide as volatile products. Biodegradation is expected to be the m a jor fate process in the aquatic ecosy stem
. The rate of biodegradation generally decreases w ith decreasing temp eratures. Naturally -occurring phy toplankton increases the degradation rate, because phy toplankton can use urea as a nitrogen source. In phy toplankton-rich waters, degradation occurs mu ch faster in sunlight than in the dark. Abiotic hy droly s is of urea occurs very slowly in relation to biotic hy droly s is (EPA, 2002a). Sulfuric Acid Sulfuric acid generally dissolves in the environm ent and release sulfate ions and hy drogen ions, and these hy drogen ions, in turn, increases the acidity of the so il or water (EPA, 1993). The extent of the increased acidity depends on the am ount of the neutralizing i ons present, the buffering capacity , and the am ount of dilution possible. 

### XI. References Chem IDplus Lite. Printed 2004. Urea, sulfate (1:1). CAS Reg. No.: 21351-39-3. http://chem

. sis.nlm

. nih.gov/chem idplus/jsp/chem idlite/ChemF ull.jsp ChemFinder.com Database and Internet Searching. Printed 2004. Urea Sulfate. http://chem f inder.cambridgesoft.com /result.asp Material Safety Data Sheet for SuperQuik TM

. Printed 2005; Date of preparation 3/8/99, with revised sections: New MSDS Issue. http://www.
8Material Safety Data Sheet for Wilthin. Printed 2005; Date of preparation 1/22/99, with revised sections: New MSDS Issue. http://www. Material Safety Data Sheet for Monocarbam i de Dihy drogen Sulfate. Printed 2004; Date of preparation 7/28/99. www.spindlerenterprises.com /files/pH_Perfect.PDF Material Safety Data Sheet for Monocarbam i de Dihy drogen Sulfate. Printed 2004; Date of preparation 9/27/04. http://www.agrium .com /products_services/m s ds/liquid.cfm Material Safety Data Sheet for Monocarbam i de Dihy drogen Sulfate Solution. Printed 2004. http://www.y ourgrowingsolutions.com /id13.htm l U.S. EPA. 1987. Monocarbam i de (Enquik, WilThin) He rbicide Profile. EPA Pesticide Fact Sheet. #151. U.S. EPA. 1993. Mineral Acids Reregistration Eligib ility Decision (RED). Prevention, Pesticides, and Toxic Substances (7508W). EPA-738-F-93-025. U.S. EPA. 1997. Monocarbam i de (Enquik, WilThin) NYSDEC Registration Approval. New York State Departm e nt of Environm ental Conservation, Di vision of Solid and Hazardous Materials. U.S. EPA. 2002a. Urea Tolerance Reassessm ent Eligibility Decision (TRED). Federal Register: April 15, 2002. Volum e 67, Numb er 72. U.S. EPA. 2002b. Tolerance Reassessm ent Decisions Co mp leted by the Inert Ingredient Focus Group (IIFG): IIFG Decision Docum e nts on Reassessing Exempti ons from the Requirem e nt of a Tolerance for the Mineral Acids, (Hy d rochloric, Carbonic, Phos phoric, and Sulfuric) and their Am m onium , Calcium , ferrous, Magnesium , Potassium , Sodium , and/or Zinc Salts.

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### Appendix 1. BEAD Screening Level Usage Analysis for Urea Sulfate for Agricultural Uses and Other Inform ation

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## Urea Sulfate (128961) Screening Level Usage Analysis (SLUA) Date: 6/2/05 What is a Screening Level Usage Analysis (SLUA)?

_ Available estim ates of pesticide usage data for a particular active ingredient that is used on agricultural crops in the United States. What does it contain?

- Pesticide usage data for a single active ingredient only

.

- Agricultural use sites (cr ops) that the pesticide is reported to be used on.

- Available pesticide usage inform ation (i.e ., does not include all of the United States).

- Annual percent of crop treated(average & maximum) for each agricultural crop.

- Average annual pounds of the pesticide applied for each agricultural crop (i.e., for the states survey ed, not for the entire United States). What assumptions can I make about the reported data?

_ Average pounds of active ingredient applied - Values are calculated by m e rging pesticide usage data sources together; averaging by y ear, averaging across all y ears, & then rounding. Note: If the estimated value is less than 500, then that value is labeled <500. Estimated values between 500 & <1,000,000 are rounded to 1 significant digit. Estimated values of 1,000,000 or greater are rounded to 2 significant digits.)

_ Average percent of crop treated - Values are calculated by m e rging data sources together; averaging by y ear, averaging across all y ears, & rounding to the nearest mu ltiple of 5. Note: If the estimated value is less than 1, then the value is labeled <1.

_ Maximum percent of crop treated - Value is the single m a ximu m value reported across all data sources, across all y ears, & rounded up to the nearest mu ltiple of 5. Note: If the estimated value is less than 2.5, then the value is labeled <2.5. What are the data sources used?

_ USDA-NASS (United States Departm e nt of Agriculture’s National Agricultural Statistics Service) – pesticide usage data from 1998 to 2003.

_ NCFAP (National Center for Food and Agricultura l Policy ) – pesticide usage data from 1997 & is only used if data is not available from the other sources.

_ Private pesticide market research – pesticide usage data from 1998 to 2003.

_ California DPR data can be requested separately

. What are the limitations to the data?

_ Additional registered uses m a y exist but are not included because the available survey s do not report usage (e.g., sm all acreage crops).

_ Lack of reported usage data for the pesticide on a crop does not imply zero usage.

_ Usage data on a particular site m a y be noted in data sources, but not quantified

. In these instances, the site would not be reported in the SLUA.

_ Non-agricultural use sites (e.g., turf, post-harvest , m o squito control, etc.) are not reported in the SLUA. A separate request mu st be m a de to receive these estim ates.

11______________________________________ Wednesday, June 1, 2005 15:24 Screening Level Estimates of Agricultural Uses of Urea Sulfate (128961) Sorted Alphabetically
Crop Lbs. A.I. Percent Crop Treated Avg. Max. 1 Apples 9,000 <1 <2.5 2 Cotton 3,000,000 5 10 3 Peppers 200,000 5 5 4 Tomatoes 80,000 <1 <2.5

All numbers rounded. '<2.5' indicates less than 2.5 percent of crop is treated.

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