UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D

. C

., 

### 20460

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION



### DP Barcodes: D411540, 414403, 416312 PC Code: 000325 Date: November 25, 2013

MEMORANDUM

SUBJECT:

FROM:

REVIEWED: BY:



### THROUGH:

TO: Drinking Water Assessment for the Proposed Uses ofMetrafenone [(3-bromo-6- methyoxy-2-methylphenyl) (2,3,4-trimethoxy-6-methylphenyl) methanone] on P0me Fruits, Fruiting Vegetables, Peach Subgroup 12-12B, Apricot, Cherry Subgroup 12-12A, Cucurbit Vegetables (Group 9), and Fruit, Small, Vine Climbing (except Fuzzy Kiwifruit) Subgroup 13-07F

James A. Hetrick, Ph.D, Senior Scienti0.du! 

# U**~u{** Environmental Risk Branch III Environmental Fate and Effects Division (7507P) 

# _c>**~**

Rosanna Louie-Juzwiak, RAPL 

# {}lu- <::f--

Rochelle Bohaty, Ph.D

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### Chemis~ 1\

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### ::::::s:::i'C~ Environmental Risk Branch III

### ~**~\** 

## ""t\ Environmental Fate and Effects Division (7507P)

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DanaSpatz,BranchChief

# ~**~ l\)"l-~]~13**  Environmental Risk Branch

### III~'~ Environmental Fate and Effects Division (7507P)

Christina Swartz, Branch Chief Registration Action Branch 2 Health Effects Division (7509P)

Barbara Madden, Team Leader Risk Integration Minor Use and Emergency Response Branch Registration Division (7505P)

Tony Kish

, Product Manager 22 Rosemary Keams, Reviewer · Cynthia Giles-Parker

, Branch Chief Fungicide Branch Registration Division (7505P)

BASF is seeking to register metrafenone for use on Pome Fruit and Fruiting Vegetables. IR-4 has requested uses ofmetrafenone on Peach Subgroup 12-12B, Apricot, Cherry Subgroup 12-12A, Cucurbit Vegetables (Group 9), and Fruit, Small

, Vine Climbing (except Fuzzy Kiwifruit) Subgroup**13~07F** 

### to control powdery mildew. These new uses are proposed on the Vivando Fungicide label (EPA Reg. No. 7969-284).

### 2 The PRZM EXAMS Tier II screening level concentrati ons in surface water for total metrafenone residues in drinking water for use in the human health dietary risk assessment are 25.64 μg/L for 1 in 10 year peak, 14.52 μg/L for the 1 in 10 year annual average, and 9.22 μg/L for the 30 year annual average. Using PRZM-GW, total metrafenone residues in groundwater are not expected to excee d 12.5 μg/L for the peak EDWC and 12.3 μg/L for the post-breakthrough concentration (current use on grape).

Total Toxic Residue Approach

An analysis of the residues of concern for metrafenone indicate that the only identified major degradation product is CL 377160 [Methanone, (3-bromo-6-methox y-2-methylphenyl)(3-hydroxy-2,4-dimethoxy-6- methylphenyl)-]. This degradation product was de tected in soil photolysis and anaerobic aquatic metabolism studies. Most degradation processes also resulted in formation of a substantial amount of minor degradates, some individually measured and id entified, but most were not. Although all of these degradates were present at less than 10%, and some at very low levels, these residues may be of exposure concern. In some cases minor degradates, mostly un identified, make up more than 50% of the applied radioactivity in a single sampling event. In additio n, based on the structure of the parent compound and the proposed degradation pathways, many of the minor degradates may have a high degree of structural similarity to each other and/or the parent resulting in a similar toxicity profile and cumulative effects. Because of the structural similarity of many degr adation products with the parent compound as well as a high number of unidentified minor degradation products, this drin king water assessment (DWA) for metrafenone was conducted using a total toxic residu es approach (TTR). The TTR consists of parent metrafenone, CL4084564, CL375228, CL377160, CL 377096, CL434223, CL377095,CL 1023424, CL 3000402,TN, MB, DG, GF, and unidentified extr actable residues (ROCKS Memorandum, 8/29/2009). This modeling approach was adopted to address uncerta inties associated with tentative identification of degradation productions and inadequa te identification of minor degradation products that may be of toxicological concern. This DWA includes estimat ed drinking water concentrations (EDWCs) for metrafenone as well as total extractable residues refe rred to collectively as total metrafenone residues.

Modeling Results for Use in the Human Health Risk Assessment

The peak EDWC for total metrafenone residues b ased on the proposed uses [Pome Fruits, Fruiting Vegetables, Peach Subgroup 12-12B, Apricot, Che rry Subgroup 12-12A, Cucurbit Vegetables (Group 9), and Fruit, Small, Vine Climbing (except Fuzzy Kiwifruit) Subgroup 13-07F] is higher than the peak EDWC for the current use on grapes (Table 1). Howeve r, the 1 in 10 year annual average and 30-year annual average EDWCs for the proposed new uses are lower than the EDWCs for the grape use. The PRZM-EXAMS Tier II screening level concentrations in surface water for total metrafenone residues in drinking water are 25.64 μg/L for 1 in 10 peak, 14.52 μg/L for the 1 in 10 year annual average, and 9.22 μg/L for the 30 year annual average. Total me trafenone residues in groundwater using PRZM-GW modeling are 12.5 μg/L for the peak EDWC and 12.3 μg/L for the post-breakthrough concentration.

### 3 Table 1: Tier II PRZM/EXAMS and Tier I PRZM-GW EDWC s for Total Metrafenone Residues in Drinking Water

Models Uses 1 in 10 year 30-year Annual Average Peak Annual Average

PRZM/EXAMS Pome Fruits, Fruiting Vegetabl es, Peach Subgroup 12-12B, Apricot, Cherry Subgroup 12-12A, Cucurbit Vegetables (Group 9), and Fruit, Small, Vine Climbing (except Fuzzy Kiwifruit) Subgroup 13-07F 25.64 7.25 5.71

PRZM/EXAMS Grapes 23.71 14.52 9.22



### PRZM-GW All Uses 12.5 12.3



## Previous Drinking Water Assessments

A previous DWA was conducted to support use of metrafenone on grapes (D355987). This DWA was conducted using a registrant proposed maximum application rate of 0.3 lb a.i./A with 6 applications, and a minimum application interval of 14 days. However, the current registered maximum use rate on grapes is 0.3 lb a.i./A with 3 applications, and a minimum application interval of 14 days. EDWCs for metrafenone and total metrafenone residues in grou ndwater and surface water are shown Tables 2 and 3.

Table 2. Estimated Drinking Water Concentrations (μg/L) for Metrafenone Resulting from Use on Grapes Models Pea k Annual Avera g e 30- y ear Annual Avera g e Surface Water EDWCs for Initially Proposed Use Rates on Grapes (0 .3 lb a.i./A, 6 applications, 14-day interval)

Tier I FIRST 42.10 4.03 NA Tier II PRZM/EXAMS 25.73 6.26 3.71 SCI-GROW NA EDWCs for Registered Use Rates on Grapes (0.3 lb a.i./A, 3 applications, 14-day interval) Tier II PRZM/EXAMS 16.79 3.26 2.12

Table 3. Estimated Drinking Water Concentrations (μ g/L) for Total Metrafenone Residues Resulting from Use on Grapes

Models Pea k Annual Avera g e 30- y ear Annual Avera g e Surface Water EDWCs for Initially Proposed Use Rates on Grapes (0 .3 lb a.i./A, 6 applications, 14-day interval)

Tier I FIRST 43.54 10.41 NA Tier II PRZM/EXAMS 39.11 22.82 15.03 SCI-GROW 0.097 NA EDWCs for Registered Use Rates on Grapes (0.3 lb a.i./A, 3 applications, 14-day interval) Tier II PRZM/EXAMS 23.71 14.52 9.22

### 4 

## Use Information

Application rates and frequency of application for the proposed and existing uses are shown in Table 4. The proposed application method is ground or aerial application. Although the label has recommendation for reducing spray drift, it does not stipulate a spray drift buffer or droplet size for the proposed uses.

Table 4. Metrafenone Use Profile [Vivando Fungicide (EPA Reg. No. 7969-284)]

Use Max. Single App. Rate (lb a.i./A) # of App. / Season Seasonal Max. Rate (lb a.i./A) Minimum App. Interval (days)

Proposed Crops and Application Rates Pome Fruit 0.3 3 0.9 7 Fruiting Vegetable 0.3 3 0.9 7 Peach Subgroup 12-12B 0.3 2 0.6 7 Apricots 0.3 2 0.6 7 Cherry Subgroup 12-12A 0.3 2 0.6 7 Hops 0.3 2 0.6 7 Cucurbits Vegetables (Group 9) 0.3 3 0.9 7 Fruit, small, vine climbing Subgroup (13-07F) 0.3 3 0.9 7

Registered Crop and Application Rate Grapes 0.3 3 0.9 14



## Environmental Fate Assessment

Metrafenone is a benzophenone chemical class that is exp ected to be slightly mobile. Its major routes of degradation are aqueous photolysis and aquatic metabolism, in bot h aerobic and anaerobic conditions. Soil metabolism is slow, with laboratory half-lives of 6 months to a year and accumulation over two years observed in field studies. In aquatic environments , the measured photolysis half-life was 6 days and metabolism in both aerobic and anaerobic occurred with half-lives of one to four weeks.

Soil photolysis and anaerobic aquatic metabolism of benzophenone led to one major degradate, CL 377160, and anaerobic aquatic metabolism also led to six other major degradates, but all were either unidentified or only tentatively identified. In add ition, there were many minor degradates, which were formed at low levels individually but reached substantial amounts as groups.

Total extractable residues of metrafenone (metrafe none TTR) are persistent in soil, aerobic aquatic metabolism, and anaerobic metabolism environments. Although parent metraf enone and metrafenone TTR are persistent in aerobic soil environments, pa rent metrafenone degrades rapidly in aerobic and anaerobic aquatic environments with subsequent formation of extractable unidentified degradation products. The inclusion of unidentif ied degradation products in the est imation of metrafenone TTR halflife is the reason for higher persistence of metrafenone TTR in a quatic environments.

### 5 Mobility

Batch equilibrium data on metrafenone suggest that the compound will sorb to organic surfaces and would be considered “slightly mobile” according to the FAO classification scheme (organic carbon partition coefficients range from 1,073 to 2,792 mg/ kg soil). Also according to FAO classification, metrafenone’s solubility in water of 0.447 mg/L is considered “slightly soluble.” It showed low volatility from soil and water with <0.5% volatilization in any la boratory study, consistent with the vapor pressure of 1.15 x 10 -6 

### mmHg. Therefore, dissipation in the environm ent is expected to occur predominantly via runoff of suspended soil and sediments to which metr afenone is adsorbed. Based on terrestrial field dissipation studies in the UK , metrafenone was detect ed at a soil depth of 20-30 cm after 2 years.

In aquatic systems, partitioning of metrafenone to sediment occurred rapidly. In one anaerobic system, half of the applied metrafenone was detected in sedim ent on the first day, and in three other systems (one anaerobic, two aerobic), at least 50% of the parent compound had partitioned to sediment within three to seven days. Including degradates, partitioning was rapid in anaerobic systems but slower in aerobic systems. In two anaerobic aquatic metabolism studies, more than half of the applied radioactivity (AR) was found in sediment within one week and radioactiv ity in the water layer was down to <5% AR in two to six weeks. However, in aerobic aquatic metabolism studies in two systems, from 8% to 28% AR remained in the water layer at study termination (100 days).

Degradation Rates

Metrafenone biodegrades slowly in terrestrial environm ents. In laboratory studies in a variety of soils, aerobic soil metabolism linear half-lives ranged from 178 to 365 days. In four of the eight soils tested, data collection extended long enough to determine a DT 50 

### , of 124 to 188 days in two silt loam soils and 272 to 362 days in a clay loam and sandy loam soil. In these two soils, metabolism appeared to slow after 272 days. No data are available for anaerobic soil metabolism rates. Photolysis on soil was observed in laboratory studies to occur with a linear half-life of 31 days.

In aquatic environments, metraf enone biodegrades in weeks to months in both aerobic and anaerobic conditions (linear half-lives of 24-27 days and 18-22 days, respectively). Considering abiotic degradation, metrafenone is photolyzed in water (half-lif e of 8.4 days), but is stable to hydrolysis at pH values from 4 to 9.

Degradation Products

The only positively identified major degradate of metrafenone was CL 377160 [Methanone, (3-bromo-6- methoxy-2-methylphenyl)(3-hydroxy-2,4-dimethoxy-6-methylphenyl)-]. CL 377160 was formed through soil photolysis at up to 18.9% AR and through anaer obic aquatic metabolism at up to 10.8% AR in the total system. It was also formed as a minor degradate through aquatic photolysis and aerobic aquatic metabolism.

In one anaerobic aquatic metabolism study, another si x degradates were formed at >9%, but these were either unidentified or only tentatively identified. These included TN (tentatively identified as a lactone compound; maximum 3.3%, 26.9% and 28.0% in the water layer, sediment and total system, respectively), MB (tentatively identified as a hydrox ylation product of TN; maximum 1.1%, 11.6% and 11.7% in the water layer, sediment and total syst em, respectively), and four unidentified degradates formed in the total system at 9.3% to 13% AR.

### 6 Carbon dioxide was also a major degradate, formed through aquatic photolysis at up to 25% AR and through all other measured processes as a minor degradate.

Most processes also resulted in formation of a subs tantial amount of minor degradates, some individually measured and identified, but most not. Although a ll of these degradates were present at less than 10%, and some at very low levels, they still may be of exposure concern because of the large overall amounts. In some cases minor degradates, mostly unidentified, make up more than 50% of the applied radioactivity in a single sampling event. In addition, based on the structure of the parent compound and the proposed degradation pathways, many of the minor degradates ma y have a high degree of structural similarity to each other and/or the parent and so may have cumulative effects.



## Exposure Modeling

The estimated drinking water concentrations (EDWCs ) were calculated using a Tier II surface water modeling (PRZM-EXAMS), and Tier I groundw ater modeling (SCI-GROW and PRZM-GW). Appropriate input parameters for metrafenone and total metrafenone residues were selected from the physical/chemical properties and environmental fate data submitted by the petitioner to support the registration of metrafenone. Input para meters were selected in accordance with US EPA-OPP EFED water model parameter selection guidelines, Guidance for Selecting Input Para meters in Modeling the Environmental Fate and Transport of Pesticides, Version 2.01, October 22, 2009. Total metrafenone residue half-lives were calculated based on the to tal concentration (expressed as percent of applied radioactivity) of extractable residues present at each sampling interval for each of the relevant environmental fate studies (Appendix A).

Additional information about the models, selection of input parameters and s cenarios can be obtained from http://www.epa.gov /oppefed1/models/water/index.htm

.



## Surface Water

Scenarios used to run PRZM and EXAMS for the pr oposed new uses are shown in Table 6. Chemical specific input parameters used for modeling are s hown in Table 5. The model EDWCs of metrafenone and total metrafenone residues for surface water are sh own in Tables 7 and 8, respectively. The default Percent Crop Area (PCA) of 0.91 was used to correct th e EDWCs [Echeverria, M., Jones, R. D., Peck, C., Ruhman, M., Shelby, A., Thawley, S., Thurman, N. Development and Use of Percent Cropped Area and Percent Turf Area Adjustment Factors in Drinking Water Exposure Assessments: 2012 Update , March 16, 2012].

### 7 Table 5. PRZM/EXAMS Input Parameters for Metr afenone and Total Extractable Metrafenone Residue

PARAMETER Metrafenone Total Extractable Metrafenone

Residues COMMENT SOURCE

Application Rate per Event 0.366 kg a.i./ha 0.366 kg a.i./ha



### Vivando Fungicide label (EPA Reg. No. 7969-284)] No. of Applications (Interval) 2 or 3 (7 day) 2 or 3 (7 day)

CAM (Chemical App. Method) 2 2 Broadcast spray

Depth of Incorporation 0 0 Default

Spray Drift Fraction / Application Efficiency 0.064 / 0.99

0.16/0.95 0.064 / 0.99

0.16/0.95 Ground Spray Aerial Spray EFED Input Guidance

Aerobic Soil Metabolism

t 1/ 2 303 days 313 days Upper 90 th percentile conference limit of the mean half-life (n=8) MRID 47267425 MRID 47267426 MRID 47267427

Aerobic Aquatic Degradation t 1/ 2 28.2 days 158 days Upper 90 th percentile confidence limit of the mean half-life (n=2) MRID 47267430

Anaerobic Aquatic Degradation t 1/ 2 25.3 days 989 days Upper 90 th percentile confidence limit of the mean half-life (n=2) MRID 47267429 MRID 47267431

Aqueous Photolysis t 1/ 2 6.4 days 27.0 days Corrected for dark control MRID 47267423

Hydrolysis t 1 / 2 0 days 0 days Stable MRID 47267422

Soil Partition Coefficient (K oc ) 2188 mL/g oc 2188 mL/g oc Average Koc MRID 47267420

Molecular Weight 409 g/mole 409 g/mole MRID 47267423

Water Solubility @ 25°C 0.474 mg/L 0.474 mg/L MRID 47267423

Vapor Pressure 1.15 x 10 -6 mmHg 1.15 x 10 -6 mmHg EPA Fact Sheet (9/06)

Percent Cropped Area 0.91 0.91 Default for agricultural crops

### 8 Table 6. Scenarios Used for Surface Water Modeling Agricultural Commodity Crop Scenario Met File First Application Date

Pome Fruit PAappleSTD NCappleSTD WAorchardNMC CAfruitSTD W14751.dvf W03812.dvf W24243.dvf W93193.dvf 5/15

Fruiting Vegetable CAtomatoSTD FLtomatoSTD PAtomatoSTD W93193.dvf W12844.dvf W14751.dvf 4/1 3/1 5/16

Peach Subgroup 12-12B GApeachSTD W03813.dvf 5/15

Apricots MIcherrySTD CAfruitSTD W14850.dvf W93193.dvf 5/15

Cherry Subgroup 12-12A MIcherrySTD W14850.dvf 5/15

Hops ORhopsSTD W24232.dvf 5/1

Cucurbits Vegetables (Group 9) MImelonSTD MOmelonSTD NJmelonSTD FLcucumber W94847.dvf W13893.dvf W13781.dvf W12844.dvf 5/30 5/10 6/1 11/16

Fruit, small, vine climbing Subgroup (13-07F) NYgrapeSTD CAgrapeSTD CAwinegrapeSTD W14860.dvf W93193.dvf W23234.dvf 7/1 3/1 4/1



## Estimated Drinking Water Con centrations (surface water)

Tier II estimated drinking water concentrations for metrafenone and total metrafenone residues for the proposed crops are shown in Tables 7 and 8.

### 9 Table 7. Percent Crop Area Corrected Estimated Ex posure Concentrations for Parent Metrafenone Only from Surface Source Drinking Water Crop Scenario Application Method 1-in-10 yr Peak 1-in-10 yr Annual Mean 30 year Annual Mean

μg/L

Pome Fruit PAapple Aerial 15.02 2.03 1.47 Ground 13.39 1.87 1.28 NC apple Aerial 22.54 2.42 1.48 Ground 21.08 2.28 1.30

WAorchard Aerial 4.65 0.95 0.68 Ground 4.50 0.68 0.41

CAfruit Aerial 4.35 0.75 0.56 Ground 3.27 0.55 0.36 Fruiting Vegetables CAtomato Aerial 5.90 0.82 0.57 Ground 3.81 0.59 0.33

FLtomato Aerial 18.92 2.38 1.72 Ground 19.58 2.32 1.63

PAtomato Aerial 18.49 1.99 1.51 Ground 17.28 1.91 1.41 Peach GApeach Aerial 3.19 0.37 0.31 Ground 1.65 0.23 0.17 Apricots MIcherry Aerial 5.09 1.17 0.86 Ground 4.95 1.02 0.69

CAfruit Aerial 3.21 0.50 0.38 Ground 2.43 0.37 0.24 Cherry Subgroup MIcherry Aerial 5.09 1.17 0.86 Ground 4.95 1.02 0.69 Hops ORhops Aerial 3.53 0.88 0.76 Ground 3.02 0.71 0.58 Cucurbits MImelon Aerial 7.95 1.60 1.21 Ground 7.68 1.40 1.00

MOmelon Aerial 16.17 1.81 1.30 Ground 16.71 1.70 1.17

NJmelon Aerial 19.96 2.48 1.48 Ground 20.41 2.37 1.33

Flcucumber Aerial 18.29 2.60 1.70 Ground 19.01 2.54 1.60 Fruit, small vine climbing Subgroup (13-07F) NYgrapes Aerial 15.27 3.08 2.09 Ground 14.64 2.94 1.91

CAgrapes Aerial 4.67 0.67 0.56 Ground 2.51 0.38 0.28

CAwinegrapes Aerial 5.23 0.95 0.70 Ground 3.11 0.66 0.41

### 10 Table 8. Percent Crop Area Corrected Estimated Ex posure Concentrations for Metrafenone Total Residues from Surface Source Drinking Water

Crop Scenario Application Method 1-in-10 yr Peak 1-in-10 yr Annual Mean 30 year Annual Mean

μg/L

Pome Fruit PAapple Aerial 18.15 7.25 5.71 Ground 16.05 6.52 4.93 NC apple Aerial 25.64 7.23 5.07 Ground 23.63 6.67 4.43

WAorchard Aerial 8.16 4.63 3.82 Ground 6.37 2.88 2.10

CAfruit Aerial 7.39 3.48 2.97 Ground 4.70 2.25 1.74 Fruiting Vegetables CAtomato Aerial 7.99 3.24 2.58 Ground 4.99 2.09 1.46

FLtomato Aerial 22.45 5.33 3.98 Ground 22.97 5.20 3.80

PAtomato Aerial 20.05 7.51 5.90 Ground 19.79 6.90 5.27 Peach GApeach Aerial 9.39 2.31 1.74 Ground 7.80 1.74 1.15 Apricots MIcherry Aerial 9.21 5.27 3.97 Ground 8.06 4.51 3.19

CAfruit Aerial 5.22 2.32 1.98 Ground 3.19 1.50 1.16 Cherry Subgroup MIcherry Aerial 9.21 5.27 3.97 Ground 8.06 4.51 3.19 Hops ORhops Aerial 5.50 2.85 2.51 Ground 4.24 2.20 1.87 Cucurbits MImelon Aerial 11.97 5.87 4.73 Ground 10.27 4.90 3.76

MOmelon Aerial 19.13 4.71 3.63 Ground 18.85 4.36 3.24

NJmelon Aerial 23.85 6.90 4.83 Ground 23.55 6.34 4.20

Flcucumber Aerial 21.27 5.05 3.71 Ground 21.20 4.91 3.51 Fruit, small vine climbing Subgroup (13-07F) NYgrapes Aerial 22.98 12.85 9.32 Ground 20.89 12.21 8.60

CAgrapes Aerial 6.82 2.89 2.59 Ground 3.77 1.57 1.29

CAwinegrapes Aerial 7.09 3.08 2.50 Ground 4.23 2.03 1.47

### 11 

## Estimated Drinking Water Con centrations (ground water)

SCI-GROW

Concentration of total residues in gr oundwater were estimated using the S creening C oncentration I n Gro und W ater model(SCI-GROW) (Version 2.3). Input parameters for SCI-GRO W modeling are shown in Table 9. Estimated concentrations of metrafenone and total metrafenone residues in groundwater are shown in Table 10.

Table 9. SCI-GROW Input Parame ters for Metrafenone and Total Extractable Metrafenone Residues Model Parameter Value Reference Metrafenone Koc (L/mg-OC) 2231 Median Koc Aerobic Soil Half-life (days) 303 days Upper 90 th percentile of the mean Total Extractable Metrafenone Residues Koc (L/mg-OC) 2231 Median Koc Aerobic Soil Half-life (days) 313 days Upper 90 th percentile of the mean

Table 10. Estimated Exposure Concentr ations of Metrafenone and Total Metrafenone Residues in Drinking Water Drawn from Ground Water.

Use Scenario Total Application Rate (lb ai/A) Total Residues Concentration (μg/L)

Metrafenone 0.6 0.033 0.9 0.049 Total Metrafenone Residues 0.6 0.034 0.9 0.052



### PRZM-GW

PRZM-GW modeling was conducted to estimate the concen trations of metrafenone and total metrafenone residues in groundwater. Input parameters for PR ZM-GW modeling are shown in Table 11. The PRZMGW modeling was conducted to simulate 2 applications of 0.366 kg/ha (0.672 kg/ha) or 3 applications of 0.366 kg/ha (1.008 kg/ha).

Table 11. PRZM-GW Input Parameters for Metrafen one and Total Extractable Metrafenone Residues Model Parameter Value Reference Metrafenone Koc (L/mg-OC) 2188 Average Koc Aerobic Soil Half-life (days) 303 days Upper 90 th percentile of the mean Hydrolysis Half-life (days) 0 (Stable) MRID 47267422 Application Date May 15 First App Date Application Rate 0.336 kg/ha Maximum Single Application Rate Number of Applications 2 and 3 Proposed uses on label EPA Reg. No. 7969-284 Application Interval 7 days Minimum Application Interval Total Extractable Metrafenone Residues Koc (L/mg-OC) 2188 Average Koc Aerobic Soil Half-life (days) 313 days Upper 90 th percentile of the mean Hydrolysis Half-life (days) 0 (Stable) MRID 47267422 Application Date May 15 First App Date Application Rate 0.336 kg/ha Maximum Single Application Rate Number of Applications 2 and 3 Proposed uses on label EPA Reg. No. 7969-284 Application Interval 7 days Minimum Application Interval

### 12 Estimated drinking water concentrations for metr afenone and total metrafenone residues from PRZM-GW are shown in Tables 12 and 13 (Appendix C). The peak concentration from PRZM-GW represent the highest concentration of metrafenone residues in ground water. The post-breakthrough concentration represents the steady-state average metrafenone resi dues concentration in groundwater over the duration of the model simulation. Because metrafenone resi due concentrations did not breakthrough into groundwater during a 30 year simulation, the PRZM-GW modeling was conducted using 100 year extended meteorological data.

Table 12. PRZM-GW Estimated Expo sure Concentrations of Metrafenone in Groundwater Source Drinking Water

Scenario Annual Application Rate (kg/ha) Peak Concentration (μg/L) Post Breakthrough Concentration (μg/L) Breakthrough Time (days) Comments FL Citrus 0.672 7.87 7.72 18172 100 years 1

1.008 11.8 11.6 GA Peanut 0.672 0.52 NE 2 No Breakthrough 100 years 1.008 0.79 NE MD Corn 0.672 3.78 3.31 18583 100 years 1.008 5.67 4.97 NC Cotton 0.672 2.43 2.3 18993 100 years 1.008 3.65 3.46 WI Corn 0.672 4.83 4.82 36126 100 years 1.008 7.24 7.23 FL Potato 0.672 0.00103 NE No Breakthrough 100 years 1.008 0.00154 NE 1-100 year simulation with 100 years of application 2-Not estimated because of no breakthrough into ground water

Table 13. PRZM-GW Estimated Exposure Concentrations of Total Metrafenone Residues in Groundwater Source Drinking Water

Scenario Annual Application Rate (kg/ha) Peak Concentration (μg/L) Post Breakthrough Concentration (μg/L) Breakthrough Time (days) Comments FL Citrus 0.672 8.35 8.2 18172 100 years 1 1.008 12.5 12.3 GA Peanut 0.672 0.59 NE 2 No Breakthrough 100 years 1.008 0.88 NE MD Corn 0.672 4.16 3.64 18583 100 years 1.008 6.24 5.46 NC Cotton 0.672 2.71 2.57 18993 100 years 1.008 4.07 3.86 WI Corn 0.672 5.24 5.28 36126 100 years 1.008 7.92 7.92 FL Potato 0.672 0.00131 NE No Breakthrough 100 years 1.008 0.00195 NE 1-100 year simulation with 100 years of application 2-Not estimated because of no breakthrough into ground water

### 13 

## Monitoring Data

There are no groundwater or surface water monitoring data available for metrafenone and its degradation products.



## Uncertainties, Assumptions, and Limitations

The proposed metrafenone label [Vivando Fungicide la bel (EPA Reg. No. 7969-284)] stipulates that the maximum application rates are on a seasonal basis in stead of an annual basis. This assessment was conducted assuming that only a single cropping season occu rs in a year. This assumption, however, may not be true for fruiting vegetable crops (FLtomato and Catomato) and cucurbits (FLcucumber) because of an extended growing season ( e.g. , more than one cropping season in a given year). Consideration of multiple seasons within a year is expected to increase the EDWCs.

Another uncertainty in the assessment is the relative toxicity of numerous metrafenone degradation products with similar structures to parent metrafenone . To address this uncertainty, the drinking water assessment was conducted for parent metrafenone as well as TTR of metrafenone residues. This assessment approach provides a bounding level exposure est imate for metrafenone residues.

### 14 

## APPENDIX A

Total Extractable Metrafenone Residue Half- lives from Laboratory Degradation Studies Study Type M R ID 1 

### Half-life (da y s) Environmental Matrix Extractable Residues

Aqueous Photolysis -23 27 Total Mass Balance - VOC - CO 2 Soil Photolysis -24 47.8 Extractable Residues Aerobic Soil -27 169.1 sandy loam soil Extractable Residues Aerobic Soil -26 210.0 clay lo am soil Extractable Residues Aerobic Soil -25 277.2 silty loam soil Extractable Residues Aerobic Soil -27 277.3 clay lo am soil Extractable Residues Aerobic Soil -27 301.4 silt loam soil Extractable Residues Aerobic Soil -26 315.1 sandy loam soil Extractable Residues Aerobic Soil -27 330.1 silt loam soil Extractable Residues Aerobic Soil -26 364.8 loamy sand soil Extractable Residues Anaerobic Aquatic -29 182.0 DI water- silty cl ay loam Water + Total Extractable Anaerobic Aquatic -31 577.6 pond-sandy loam Water + Total Extractable Aerobic Aquatic -30 91.2 river-loam Water + Organic Extractable Aerobic Aquatic -30 123.8 pond-sand Total Mass Balance - VOC - CO 2 1- Prefix MRID number is 472674-

### 15 

## APPENDIX B

PRZM EXAMS Sample Outputs



### NC Apple (Aerial)-Metrafenone TTR

stored as NCapp.out Chemical: metrafenone PRZM environment: NCappleSTD.txt m odified Tueday, 29 May 2007 at 13:58:16 EXAMS environment: ir298.exv modified Tueday, 26 August 2008 at 06:14:08 Metfile: w03812.dvf modified Tueday, 26 August 2008 at 06:14:10 Water segment concentrations (ppb)

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly 1965 7.394 7.008 6.254 5.371 4.742 2.109 1966 10.95 10.42 9.153 7.574 7.469 4.437 1967 20.32 19.28 16.55 13.6 12.14 6.727 1968 13.48 12.88 11.05 9.737 9.59 6.248 1969 16.7 15.87 13.22 10.23 8.911 5.756 1970 7.819 7.524 6.716 5.616 5.771 4.439 1971 9.711 9.27 7.973 6.872 6.496 4.077 1972 22.82 21.56 17.45 13.35 11.35 5.912 1973 30.91 29.8 24.87 18.69 17.11 8.858 1974 10.08 9.744 8.811 8.347 8.275 6.197 1975 16.97 16.14 13.48 10.35 9.09 5.583 1976 27 25.61 21.23 16.95 14.63 7.557 1977 9.404 9.064 8.451 7.685 7.186 5.976 1978 12.19 11.66 10.09 8.159 7.277 5.368 1979 9.764 9.345 8.669 7.263 6.8 4.719 1980 10.18 9.736 8.245 7.777 7.037 4.267 1981 25.79 24.56 20.38 15.1 12.64 6.15 1982 12.27 11.76 10.84 8.991 8.791 5.856 1983 8.613 8.273 7.551 6.383 5.692 4.289 1984 9.573 9.125 7.701 7.188 7.125 4.449 1985 13.24 12.59 10.55 7.917 6.856 4.48 1986 10.75 10.25 8.844 7.153 6.473 4.584 1987 38.43 36.28 30.26 22.47 18.72 9.094 1988 9.492 9.186 8.317 7.146 6.766 5.925 1989 15.94 15.23 13.22 10.92 9.765 5.665 1990 14.96 14.46 12.4 10.05 9.498 6.059

Sorted results Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly 0.037037037037037 38.43 36.28 30.26 22.47 18.72 9.094 0.0740740740740741 30.91 29.8 24.87 18.69 17.11 8.858 0.111111111111111 27 25.61 21.23 16.95 14.63 7.557 0.148148148148148 25.79 24.56 20.38 15.1 12.64 6.727 0.185185185185185 22.82 21.56 17.45 13.6 12.14 6.248 0.222222222222222 20.32 19.28 16.55 13.35 11.35 6.197 0.259259259259259 16.97 16.14 13.48 10.92 9.765 6.15 0.296296296296296 16.7 15.87 13.22 10.35 9.59 6.059 0.333333333333333 15.94 15.23 13.22 10.23 9.498 5.976 0.37037037037037 14.96 14.46 12.4 10.05 9.09 5.925 0.407407407407407 13.48 12.88 11.05 9.737 8.911 5.912 0.444444444444444 13.24 12.59 10.84 8.991 8.791 5.856 0.481481481481481 12.27 11.76 10.55 8.347 8.275 5.756 0.518518518518518 12.19 11.66 10.09 8.159 7.469 5.665 0.555555555555556 10.95 10.42 9.153 7.917 7.277 5.583 0.592592592592593 10.75 10.25 8.844 7.777 7.186 5.368 0.62962962962963 10.18 9.744 8.811 7.685 7.125 4.719 0.666666666666667 10.08 9.736 8.669 7.574 7.037 4.584 0.703703703703704 9.764 9.345 8.451 7.263 6.856 4.48 0.740740740740741 9.711 9.27 8.317 7.188 6.8 4.449 0.777777777777778 9.573 9.186 8.245 7.153 6.766 4.439 0.814814814814815 9.492 9.125 7.973 7.146 6.496 4.437 0.851851851851852 9.404 9.064 7.701 6.872 6.473 4.289 0.888888888888889 8.613 8.273 7.551 6.383 5.771 4.267

### 16 0.925925925925926 7.819 7.524 6.716 5.616 5.692 4.077 0.962962962962963 7.394 7.008 6.254 5.371 4.742 2.109

0.1 28.173 26.867 22.322 17.472 15.374 7.9473 Average of yearly averages: 5.5685

Inputs generated by pe 5.pl - Novemeber 2006

Data used for this run: Output File: NCapp Metfile: w03812.dvf PRZM scenario: NCappleSTD.txt EXAMS environment file: ir298.exv Chemical Name: metrafenone Description Variable Name Value Units Comments Molecular weight mwt 409 g/mol Henry's Law Const. henry atm-m^3/mol Vapor Pressure vapr 1.15E-6 torr Solubility sol 0.474 mg/L Kd Kd mg/L Koc Koc 2188 mg/L Photolysis half-life kdp 27 days Half-life Aerobic Aquatic Metabolism kbacw 158 days Halfife Anaerobic Aquatic Metabolism kbacs 989 days Halfife Aerobic Soil Metabolism asm 313 days Halfife Hydrolysis: pH 7 days Half-life Method: CAM 2 integer See PRZM manual Incorporation Depth: DEPI cm Application Rate: TAPP 0.336 kg/ha Application Efficiency: APPEFF 0.95 fraction Spray Drift DRFT 0.16 fraction of application rate applied to pond Application Date Date 15-5 dd/mm or dd/mmm or dd-mm or dd-mmm Interval 1 interval 7 days Set to 0 or delete line for single app. app. rate 1 apprate 0.336 kg/ha Interval 2 interval 7 days Set to 0 or delete line for single app. app. rate 2 apprate 0.336 kg/ha Record 17: FILTRA IPSCND 1 UPTKF Record 18: PLVKRT PLDKRT FEXTRC 0.5 Flag for Index Res. Run IR Reservoir Flag for runoff calc. RUNOFF total none, monthly or total(average of entire run) 

### PA Apple (Aerial)-Metrafenone TTR

stored as PAapp.out Chemical: metrafenone PRZM environment: PAappleSTD_V2.txt m odified Tueday, 20 May 2008 at 13:00:22 EXAMS environment: ir298.exv modified Tueday, 26 August 2008 at 06:14:08 Metfile: w14751.dvf modified Tueday, 26 August 2008 at 06:15:00 Water segment concentrations (ppb)

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly 1961 8.419 7.986 6.922 6.23 5.613 2.591 1962 7.218 6.939 6.419 5.621 5.195 4.184 1963 7.77 7.476 6.581 5.527 5.052 4.176 1964 8.338 8.031 7.378 6.474 6.05 4.608 1965 7.739 7.449 6.666 5.683 5.236 4.144 1966 15.32 14.61 12.37 9.647 8.653 5.086 1967 12.03 11.68 10.52 9.432 8.752 6.767 1968 14.97 14.57 12.57 9.822 8.665 6.668 1969 23.98 22.83 19.68 14.9 12.96 7.869 1970 11.42 11.07 10.33 9.74 9.383 7.386 1971 13.19 12.65 10.83 9.234 8.282 6.224 1972 61.41 58.12 47.17 33.42 28.14 13.6 1973 18.04 17.51 15.74 13.45 12.4 10.96 1974 11.08 10.79 9.984 9.344 8.828 7.922

### 17 1975 17.75 17.05 14.74 11.91 10.71 7.974 1976 11.95 11.54 10.41 8.87 8.482 7.385 1977 9.392 9.094 8.228 7.279 6.69 5.652 1978 11.35 10.92 9.752 8.125 7.692 5.466 1979 9.348 9.014 8.077 7.095 6.553 5.505 1980 9.247 8.908 8.03 6.618 5.906 4.603 1981 8.28 7.993 7.128 6.389 6.287 4.913 1982 20.16 19.37 18.39 14.77 12.87 7.061 1983 11.16 10.78 9.873 8.145 7.31 5.702 1984 16.45 15.77 13.82 12.38 10.98 6.961 1985 10.37 10.04 9.143 7.825 7.111 5.771 1986 10.45 10.09 9.043 7.592 6.982 5.603 1987 9.626 9.284 8.123 7.438 6.838 5.742 1988 8.928 8.626 7.743 6.522 6.457 5.19 1989 10.56 10.25 9.173 8.592 8.285 5.738 1990 17.83 17.06 14.37 11.26 10.13 6.841

Sorted results Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly 0.032258064516129 61.41 58.12 47.17 33.42 28.14 13.6 0.0645161290322581 23.98 22.83 19.68 14.9 12.96 10.96 0.0967741935483871 20.16 19.37 18.39 14.77 12.87 7.974 0.129032258064516 18.04 17.51 15.74 13.45 12.4 7.922 0.161290322580645 17.83 17.06 14.74 12.38 10.98 7.869 0.193548387096774 17.75 17.05 14.37 11.91 10.71 7.386 0.225806451612903 16.45 15.77 13.82 11.26 10.13 7.385 0.258064516129032 15.32 14.61 12.57 9.822 9.383 7.061 0.290322580645161 14.97 14.57 12.37 9.74 8.828 6.961 0.32258064516129 13.19 12.65 10.83 9.647 8.752 6.841 0.354838709677419 12.03 11.68 10.52 9.432 8.665 6.767 0.387096774193548 11.95 11.54 10.41 9.344 8.653 6.668 0.419354838709677 11.42 11.07 10.33 9.234 8.482 6.224 0.451612903225806 11.35 10.92 9.984 8.87 8.285 5.771 0.483870967741936 11.16 10.79 9.873 8.592 8.282 5.742 0.516129032258065 11.08 10.78 9.752 8.145 7.692 5.738 0.548387096774194 10.56 10.25 9.173 8.125 7.31 5.702 0.580645161290323 10.45 10.09 9.143 7.825 7.111 5.652 0.612903225806452 10.37 10.04 9.043 7.592 6.982 5.603 0.645161290322581 9.626 9.284 8.228 7.438 6.838 5.505 0.67741935483871 9.392 9.094 8.123 7.279 6.69 5.466 0.709677419354839 9.348 9.014 8.077 7.095 6.553 5.19 0.741935483870968 9.247 8.908 8.03 6.618 6.457 5.086 0.774193548387097 8.928 8.626 7.743 6.522 6.287 4.913 0.806451612903226 8.419 8.031 7.378 6.474 6.05 4.608 0.838709677419355 8.338 7.993 7.128 6.389 5.906 4.603 0.870967741935484 8.28 7.986 6.922 6.23 5.613 4.184 0.903225806451613 7.77 7.476 6.666 5.683 5.236 4.176 0.935483870967742 7.739 7.449 6.581 5.621 5.195 4.144 0.967741935483871 7.218 6.939 6.419 5.527 5.052 2.591

0.1 19.948 19.184 18.125 14.638 12.823 7.9688 Average of yearly averages: 6.2764

Inputs generated by pe 5.pl - Novemeber 2006

Data used for this run: Output File: PAapp Metfile: w14751.dvf PRZM scenario: PAappleSTD_V2.txt EXAMS environment file: ir298.exv Chemical Name: metrafenone Description Variable Name Value Units Comments Molecular weight mwt 409 g/mol Henry's Law Const. henry atm-m^3/mol Vapor Pressure vapr 1.15E-6 torr Solubility sol 0.474 mg/L Kd Kd mg/L Koc Koc 2188 mg/L Photolysis half-life kdp 27 days Half-life Aerobic Aquatic Metabolism kbacw 158 days Halfife

### 18 Anaerobic Aquatic Metabolism kbacs 989 days Halfife Aerobic Soil Metabolism asm 313 days Halfife Hydrolysis: pH 7 days Half-life Method: CAM 2 integer See PRZM manual Incorporation Depth: DEPI cm Application Rate: TAPP 0.336 kg/ha Application Efficiency: APPEFF 0.95 fraction Spray Drift DRFT 0.16 fraction of application rate applied to pond Application Date Date 15-5 dd/mm or dd/mmm or dd-mm or dd-mmm Interval 1 interval 7 days Set to 0 or delete line for single app. app. rate 1 apprate 0.336 kg/ha Interval 2 interval 7 days Set to 0 or delete line for single app. app. rate 2 apprate 0.336 kg/ha Record 17: FILTRA IPSCND 1 UPTKF Record 18: PLVKRT PLDKRT FEXTRC 0.5 Flag for Index Res. Run IR Reservoir Flag for runoff calc. RUNOFF total none, monthly or total(average of entire run)



### NYGrapes (Aerial)-14 day interval-Metrafenone TTR

stored as NYgrap14.out Chemical: metrafenone PRZM environment: NYGrapesSTD.txt modi fied Tueday, 29 May 2007 at 13:59:44 EXAMS environment: ir298.exv modified Tueday, 26 August 2008 at 06:14:08 Metfile: w14860.dvf modified Tueday, 26 August 2008 at 06:15:12 Water segment concentrations (ppb)

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly 1961 4.708 4.531 3.816 3.078 2.77 1.229 1962 21.36 20.51 17.66 14.37 13.22 6.133 1963 12.37 12.01 10.99 9.9 9.267 8.137 1964 25.64 24.71 21.56 17.46 15.77 9.72 1965 14.64 14.26 13.6 12.74 12.25 10.4 1966 17.55 17.02 15.23 12.9 11.93 9.529 1967 15.5 15.15 14.21 13.25 12.61 9.39 1968 10.92 10.61 9.69 9.015 8.628 7.702 1969 9.548 9.275 8.464 7.845 7.332 6.444 1970 18.21 17.53 16.64 14.57 14.31 8.589 1971 15.74 15.29 14.18 12.62 11.96 9.804 1972 13.1 12.77 11.91 11.09 10.69 8.977 1973 11.9 11.59 10.51 9.163 8.77 7.457 1974 13 12.62 11.44 9.963 9.263 7.27 1975 21.97 21.34 19.52 16.51 15.18 10.15 1976 13.12 12.79 12.1 11.36 11.21 9.781 1977 25.86 25.34 24.06 21.2 19.89 12.04 1978 26.08 25.3 23.17 20.55 19.27 14.55 1979 27.01 26.27 23.83 21.64 20.82 15.29 1980 31.12 30.2 27.03 23.83 22.2 16.59 1981 19.37 19.08 17.77 16.51 15.92 14.27 1982 17.21 16.76 15.32 13.83 13.2 11.69 1983 25.42 24.61 23.12 19.7 18.4 12.04 1984 18.34 17.88 16.39 14.26 13.3 11.51 1985 14.91 14.52 13.44 12.03 11.19 10.13 1986 19.18 18.54 17.58 14.73 13.58 10.1 1987 23.7 22.91 20.38 19.3 18.2 12.24 1988 20.49 19.87 17.73 16.28 15.55 12.31 1989 14.68 14.31 13.09 12.31 11.69 10.38 1990 21.31 20.64 19.51 16.86 15.66 10.33

Sorted results Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly 0.032258064516129 31.12 30.2 27.03 23.83 22.2 16.59 0.0645161290322581 27.01 26.27 24.06 21.64 20.82 15.29 0.0967741935483871 26.08 25.34 23.83 21.2 19.89 14.55

### 19 0.129032258064516 25.86 25.3 23.17 20.55 19.27 14.27 0.161290322580645 25.64 24.71 23.12 19.7 18.4 12.31 0.193548387096774 25.42 24.61 21.56 19.3 18.2 12.24 0.225806451612903 23.7 22.91 20.38 17.46 15.92 12.04 0.258064516129032 21.97 21.34 19.52 16.86 15.77 12.04 0.290322580645161 21.36 20.64 19.51 16.51 15.66 11.69 0.32258064516129 21.31 20.51 17.77 16.51 15.55 11.51 0.354838709677419 20.49 19.87 17.73 16.28 15.18 10.4 0.387096774193548 19.37 19.08 17.66 14.73 14.31 10.38 0.419354838709677 19.18 18.54 17.58 14.57 13.58 10.33 0.451612903225806 18.34 17.88 16.64 14.37 13.3 10.15 0.483870967741936 18.21 17.53 16.39 14.26 13.22 10.13 0.516129032258065 17.55 17.02 15.32 13.83 13.2 10.1 0.548387096774194 17.21 16.76 15.23 13.25 12.61 9.804 0.580645161290323 15.74 15.29 14.21 12.9 12.25 9.781 0.612903225806452 15.5 15.15 14.18 12.74 11.96 9.72 0.645161290322581 14.91 14.52 13.6 12.62 11.93 9.529 0.67741935483871 14.68 14.31 13.44 12.31 11.69 9.39 0.709677419354839 14.64 14.26 13.09 12.03 11.21 8.977 0.741935483870968 13.12 12.79 12.1 11.36 11.19 8.589 0.774193548387097 13.1 12.77 11.91 11.09 10.69 8.137 0.806451612903226 13 12.62 11.44 9.963 9.267 7.702 0.838709677419355 12.37 12.01 10.99 9.9 9.263 7.457 0.870967741935484 11.9 11.59 10.51 9.163 8.77 7.27 0.903225806451613 10.92 10.61 9.69 9.015 8.628 6.444 0.935483870967742 9.548 9.275 8.464 7.845 7.332 6.133 0.967741935483871 4.708 4.531 3.816 3.078 2.77 1.229

0.1 26.058 25.336 23.764 21.135 19.828 14.522 Average of ye arly averages: 10.1394

Inputs generated by pe 5.pl - Novemeber 2006

Data used for this run: Output File: NYgrap14 Metfile: w14860.dvf PRZM scenario: NYGrapesSTD.txt EXAMS environment file: ir298.exv Chemical Name: metrafenone Description Variable Name Value Units Comments Molecular weight mwt 409 g/mol Henry's Law Const. henry atm-m^3/mol Vapor Pressure vapr 1.15E-6 torr Solubility sol 0.474 mg/L Kd Kd mg/L Koc Koc 2188 mg/L Photolysis half-life kdp 27 days Half-life Aerobic Aquatic Metabolism kbacw 158 days Halfife Anaerobic Aquatic Metabolism kbacs 989 days Halfife Aerobic Soil Metabolism asm 313 days Halfife Hydrolysis: pH 7 days Half-life Method: CAM 2 integer See PRZM manual Incorporation Depth: DEPI cm Application Rate: TAPP 0.336 kg/ha Application Efficiency: APPEFF 0.95 fraction Spray Drift DRFT 0.16 fraction of application rate applied to pond Application Date Date 1-7 dd/mm or dd/mmm or dd-mm or dd-mmm Interval 1 interval 14 days Set to 0 or delete line for single app. app. rate 1 apprate 0.336 kg/ha Interval 2 interval 14 days Set to 0 or delete line for single app. app. rate 2 apprate 0.336 kg/ha Record 17: FILTRA IPSCND 1 UPTKF Record 18: PLVKRT PLDKRT FEXTRC 0.5 Flag for Index Res. Run IR Reservoir Flag for runoff calc. RUNOFF total none, monthly or total(average of entire run)

### 20 

## APPENDIX C

PRZM-GW Metrafenone Total Residues- FL Citrus Scenario