![](media/image1.wmf){width="1.3576388888888888in"
height="1.375in"}UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

PC Code: 071503 DP Barcode: D342828, 348540

> Date: March 12, 2008

**[MEMORANDUM]{.underline}**

**SUBJECT:** Tier I Drinking Water Assessment for the Fludioxonil
Proposed New Use on Grapes; and the Proposed IR-4 New Uses on Tomato,
Avocado and Related Tropical Fruits, Herb Subgroup 19A, Root Vegetables,
Leaves of Root Vegetables, Lemon, Lime, Cucurbits, and Tuberous and Corm
Vegetables (Except Potato Subgroup, Except Yam)

TO: Sidney Jackson, Risk Manager Reviewer

Barbara Madden, Team Leader

Minor Use Team

Registration Division (7505P)

> Lisa Jones, Risk Manager Reviewer\
> Mary Waller, Team Leader\
> Fungicide Branch
>
> Registration Division (7505P)
>
> John Redden, Team Leader
>
> ARIA
>
> Registration Division (7505P)

**FROM:** Cheryl Sutton, Ph.D., Environmental Scientist

Environmental Risk Branch IV

Environmental Fate and Effects Division (7507P**)**

**REVIEWED**

**BY:** R. David Jones, Ph.D., Senior Agronomist

> Environmental Risk Branch IV

Environmental Fate and Effects Division (7507P**)**

# APPROVED

**BY:** Elizabeth Behl, Branch Chief

Environmental Risk Branch IV

Environmental Fate and Effects Division (7507P**)**

**[EXECUTIVE SUMMARY]{.underline}**

This memo summarizes the Tier I Estimated Drinking Water Concentrations
(EDWC) for fludioxonil in drinking water for the proposed Section 3 new
use on grapes, and the proposed IR-4 new uses on tomato, avocado and
related tropical fruits, herb subgroup 19A, root vegetables, leaves of
root vegetables, lemon, lime, cucurbits, and tuberous and corm
vegetables (except potato subgroup, except yam). Fludioxonil (CAS
131341-86-1), a fungicide, is the active ingredient in the pesticides
SCHOLAR (EPA Reg. No. 100-969), Scholar EC Fungicide (EPA Reg. No.
100-1242), and Medallion® (EPA Reg. No. 100-769); and is an active
ingredient (along with cyprodinil) in the pesticide SWITCH® 62.5 WG (EPA
Reg. No. 100-953). Similar to previous assessments, this evaluation is
limited to the risks associated with fludioxonil alone and does not
include risks associated with fludioxonil in combination with
cyprodinil.

The assessment is a Tier I screening-level assessment conducted using
the models SCIGROW and FIRST with maximum application rates. Additional
refinements of the assessment can be developed with higher tier
analysis, if requested by HED.

The maximum proposed application rate among the proposed new uses
considered for this assessment is 0.2188 lbs ai/acre/application,
applied four times per year with a 7-day reapplication interval
following the first application and a 21-day reapplication interval for
subsequent applications for a maximum total annual application rate of
0.875 lb ai/A/yr. Application intervals are based on the label
recommendation for resistance management which states that application
of the fludioxonil-containing product should be alternated with another
fungicide with a different mode of action for two applications (after
the initial two applications). All applications are by ground spray with
the exception of a single aerial application allowed for tropical fruits
in CA.

The application rate stated above is for all of the crops listed above
with the exception of lemon & lime, for which the maximum single and
total annual application rate is only 0.2188 ai/acre/application; repeat
applications are not allowed for these crops. A second exception is
tuberous and corm vegetables, for which fludioxonil is used as a
post-harvest treatment. EFED assumes that the proposed post-harvest use
of fludioxonil is an indoor use that would represent a minimal risk to
drinking water; thus, no drinking water numbers are provided for this
proposed use. The IR-4 petition does not discuss how spent treatment
solution will be disposed; however, EFED presumes that spent treatment
solution will be disposed of in a manner that does not represent a means
of entry into drinking water or a route of exposure for non-target
plants and wildlife.

The computer models FIRST (surface water) and SCI-GROW (groundwater)
were used to develop the EDWCs for use in the human health risk
assessment. Because the maximum application rates for the new uses
assessed here are less than the application rate for turf grass, the
values for turf grass are recommended for use in the human health risk
assessment. In a previous Tier 1 drinking water assessment for
fludioxonil on turf grass (drinking water memo of January 2, 2003; DP
Barcodes 285197, 285514, 286372, 286717), an application rate of 0.67
lb/acre applied 6 times was used. The registrant has indicated that this
rate applies to the product and not the active ingredient. The label
application rate for turf grass, which is used in this current
assessment, is three applications of 0.67 lb ai/A applied using 14-day
intervals, for a total application rate of 2 lb ai/A/yr.

For ground spray/foliar applications to turf grass, the estimated annual
acute concentration of fludioxonil in surface water sources of drinking
water is **81.3 μg/L** (ppb). The estimated chronic concentration is
**37.4 μg/L**. Values were not corrected for the percentage crop area
(PCA) because the default for turf grass is 1.0. The FIRST output file
is attached. As a point of reference, the previously reported acute and
chronic values were 132 and 49 ppb.

For groundwater sources of drinking water, the estimated concentration
of fludioxonil in shallow groundwater is **0.20 μg/L.** The SCIGROW
output file is attached. As a point of reference, the previously
reported value was 0.35 ppb.

Modeling results for fludioxonil in surface water and groundwater are
presented below in **Table 1**.

**Table 1. Maximum Tier I Estimated Drinking Water Concentrations in
surface water based on fludioxonil use on turf grass at 2 lb ai/A/yr.**

  ------------------- -------------------- --------------- ---------------
  **DRINKING WATER    **USE (rate          **MAXIMUM       
  SOURCE (MODEL       modeled)**           ESTIMATED       
  USED)**                                  DRINKING WATER  
                                           CONCENTRATION   
                                           (EDWC) ( ppb)** 

  Groundwater         Turf grass (0.67     Acute and       0.20
  (SCIGROW)           lbs. a.i./A/applic.  Chronic         
                      x 3 applic.; total                   
                      rate of 2 lb ai/A/yr                 
                      )                                    

  Surface Water       Turf grass (0.67     Acute           81.3
  (FIRST)             lbs. a.i./A/applic.                  
                      x 3 applic.; total                   
                      rate of 2 lb ai/A/yr                 
                      )                                    

                      Turf grass (0.67     Chronic         37.4
                      lbs. a.i./A/applic.                  
                      x 3 applic.; total                   
                      rate of 2 lb ai/A/yr                 
                      )                                    
  ------------------- -------------------- --------------- ---------------

This assessment is based on available environmental fate data. There are
no significant data gaps in the environmental fate database submitted by
the registrant. Although data are not available for anaerobic aquatic
metabolism, the anaerobic phase of the anaerobic soil metabolism study
indicates that fludioxonil is stable under such conditions.

**[PROBLEM FORMULATION]{.underline}**

This is a Tier I drinking water assessment (DWA) that uses modeling and
available monitoring data to estimate the groundwater and surface water
concentrations of pesticides in drinking water source water
(pre-treatment) resulting from pesticide use on sites that are
vulnerable. Tier I DWAs are designed to screen out chemicals with low
potential risk for posing a drinking water concern.

**[ANALYSIS]{.underline}**

**Use Characterization**

Fludioxonil is a phenylpyrrole derivative of an antibiotic produced by
the soil-borne bacterium *Pseudomonas.* It is intended to control
certain post-harvest diseases caused by *Monilinia fructicola* and *M.
laxa* (brown rot), *Botrytis cinerea* (gray mold), and *Rhizopus
stolonifer* (Rhizopus rot). A suggested mode of action of phenylpyrroles
derivatives is inhibition of the trans‑membrane transport associated
with glucose phosphorylation.

Application information is presented in **Table 2**.

**[Table 2. Summary use information for fludioxonil proposed new uses
and turf grass.]{.underline}**

  ------------ ----------- ----------- -------------- ------------ -------------- -----------------
  **Use**      **Max.      **No. of    **Annual       **Interval   **Applic.      **Incorporation
               Single      Applic.**   Applic. Rate   Between      Method**       Depth (inches)**
               Applic.                 (lbs.          Applic.                     
               Rate (lbs.              a.i./A/yr)**   (days)**                    
               a.i./A)**                                                          

  Multiple new 0.2188 lbs  4           0.875 lb       7 days       Ground         Not Applicable
  use crops^1^ ai/A                    ai/A/yr        (1^st^       spray^3^       
                                                      interval),                  
                                                      then 21                     
                                                      days^2^                     

  Lemon, lime  0.2188 lbs  1           0.2188 lbs     Not          Ground spray   Not Applicable
               ai/A                    ai/A/yr        Applicable                  

  Tuberous and 16 oz.      30-second   Not Applicable Not          Post-Harvest   Not Applicable
  Corm         Scholar/    dip                        Applicable   Dip            
  Vegetables   100 gal                                                            
               water or                                                           
               wax/                                                               
               emulsion                                                           

  Grapes       0.2188 lbs  4           0.875 lb       7 days       Ground spray   Not Applicable
               ai/A                    ai/A/yr                     (or aerial in  
                                                                   CA only for    
                                                                   1^st^ applic.) 

  Turf grass   3 apps of   3           2 lb ai/A/yr   14 days      Ground spray   Not Applicable
               0.67 lb                                                            
               ai/A                                                               
  ------------ ----------- ----------- -------------- ------------ -------------- -----------------

^1^Tomato, Avocado and Related Tropical Fruits, Herb Subgroup 19A, Root
Vegetables, Leaves of Root Vegetables, and Cucurbits. ^2^Application
intervals are based on the label recommendation for resistance
management which states that application of the fludioxonil-containing
product should be alternated with another fungicide with a different
mode of action for two applications (after the initial two
applications). ^3^ All are applications are by ground spray with the
exception of a single aerial application allowed for tropical fruits in
CA.

**Environmental Fate and Transport Characterization**

Fludioxonil is persistent, with a laboratory soil metabolism half-life
of 220 days, and field dissipation half-lives ranging from 95 to 440
days. Photolysis is a major route of degradation, with a (near-surface)
soil half-life of 1.6 days and an aqueous (near-surface) half-life of
8.7 days. Fludioxonil is slightly to moderately mobile (FAO
classification scheme) in soil (K~oc~ = 991 - 2440 mL/g~oc~) and is
primarily a concern for surface waters. Degradates of fludioxonil are
highly mobile; however, none of the four major degradates are considered
to be of toxicological concern. The fludioxonil physical and chemical
properties, and the environmental fate source data from submitted
studies are presented in **Table 3**.

There is a potential for fludioxonil to reach surface water through
spray drift, as the compound may be applied by ground spray and aerial
spray (in CA, limited crops). Because fludioxonil is persistent in
surface soils, there is also the potential for it to reach surface water
through surface runoff either in solution or adsorbed to the soil. Based
on the moderately high adsorption coefficients and the low solubility
(1.5 ppm), it is unlikely that there will be significant contamination
of surface water with fludioxonil through subsurface flow.

**Table 3. Physical/chemical properties and environmental fate source
data for fludioxonil.**

+----------------------+-----------------------+--------+-------------+
| # Property           | **Value**             | **So   | *           |
|                      |                       | urce** | *Comments** |
+----------------------+-----------------------+--------+-------------+
| # Chemical Name      | dinitrophe            | **--** | --          |
|                      | nyl-U-^14^C\]-labeled |        |             |
|                      | N-(2-chloro-          |        |             |
|                      | 6-fluorobenzyl)-N-eth |        |             |
|                      | yl-α,α,α-trifluoro-2, |        |             |
|                      | 6-dinitro-p-toluidine |        |             |
+----------------------+-----------------------+--------+-------------+
| **Molecular Weight** | 248.19                | P      | --          |
|                      |                       | roduct |             |
|                      |                       | che    |             |
|                      |                       | mistry |             |
+----------------------+-----------------------+--------+-------------+
| **Solubility in      | 1.5 mg/L              | P      | --          |
| Water (20 °C)**      |                       | roduct |             |
|                      |                       | che    |             |
|                      |                       | mistry |             |
+----------------------+-----------------------+--------+-------------+
| **Vapor Pressure (20 | 5.33 10^-9^ Torr      | P      | --          |
| °C)**                |                       | roduct |             |
|                      |                       | che    |             |
|                      |                       | mistry |             |
+----------------------+-----------------------+--------+-------------+
| **Hydrolysis         | Stable                | MRID   | --          |
| Half-life (pH 7;     |                       | 43     |             |
| 25C)**               |                       | 152502 |             |
+----------------------+-----------------------+--------+-------------+
| **Aqueous Photolysis | 8.7                   | MRID   | --          |
| Half-life (@ pH 7;   |                       | 43     |             |
| in days)**           |                       | 496302 |             |
+----------------------+-----------------------+--------+-------------+
| **Soil Photolysis    | 1.6                   | MRID   | (corrected  |
| Half-life (days)**   |                       | 43     | for natural |
|                      |                       | 496303 | sunlight at |
|                      |                       |        | 40N        |
|                      |                       |        | latitude)   |
+----------------------+-----------------------+--------+-------------+
| **Aerobic Soil       | 143, 220, 183, 365,   | MRIDs  | --          |
| Metabolism Half-life | 365, 325, 239, 154    | 433    |             |
| (days)**             |                       | 80513, |             |
|                      |                       | 471    |             |
|                      |                       | 69301, |             |
|                      |                       | 4716   |             |
|                      |                       | 9302a, |             |
|                      |                       | 4716   |             |
|                      |                       | 93012, |             |
|                      |                       | 4716   |             |
|                      |                       | 93013, |             |
|                      |                       | 471    |             |
|                      |                       | 693014 |             |
+----------------------+-----------------------+--------+-------------+
| **Anaerobic Soil     | 0, 0 (stable)         | MRIDs  | --          |
| Metabolism Half-life |                       | 4716   |             |
| (days)**             |                       | 9302b, |             |
|                      |                       | 47     |             |
|                      |                       | 169303 |             |
+----------------------+-----------------------+--------+-------------+
| **Aerobic Aquatic    | 0 (stable)            | 47     | --          |
| Metabolism Half-life |                       | 169304 |             |
| (days)**             |                       |        |             |
+----------------------+-----------------------+--------+-------------+
| **Anaerobic Aquatic  | No Data               | **--** | --          |
| Metabolism Half-life |                       |        |             |
| (days)**             |                       |        |             |
+----------------------+-----------------------+--------+-------------+
| **Soil Partition     | 8.64, 5.61, 21.3,     | MRID   | in sand     |
| Coefficient (K~d~)** | 29.8 mL/g             | 44     | (0.58% oc), |
|                      |                       | 382311 | sandy loam  |
|                      |                       |        | (0.23% oc), |
|                      |                       |        | loam (2.15% |
|                      |                       |        | oc), and    |
|                      |                       |        | loam (2.38% |
|                      |                       |        | oc)         |
+----------------------+-----------------------+--------+-------------+
| **Organic            | 1490, 2440, 991, 1250 | MRID   | --          |
| Carbon-Normalized    | mL/g~oc~              | 44     |             |
| Soil Partition       |                       | 382311 |             |
| Coeffic. (K~oc~)**   |                       |        |             |
+----------------------+-----------------------+--------+-------------+
| **Henry's Law        | 1.16 x 10^-9^         |        | --          |
| Constant**           | atm-m^3^-mole^-1^     |        |             |
+----------------------+-----------------------+--------+-------------+
| **Bioconcentration   | 430X                  | MRID   | --          |
| Factor in Fish       |                       | 44     |             |
| (BCF)**              |                       | 382320 |             |
+----------------------+-----------------------+--------+-------------+

**Drinking Water Exposure Modeling**

***Models***

An Estimated Drinking Water Concentration (EDWC) in groundwater was
estimated using EFED's Tier I aquatic model SCIGROW (Screening
Concentration in Ground Water, version 2.3; 8/8/2003). SCIGROW is a
regression model used as a screening tool to estimate pesticide
concentrations found in ground water used as drinking water. SCIGROW was
developed by fitting a linear model to groundwater concentrations with
the Relative Index of Leaching Potential (RILP) as the independent
variable. Groundwater concentrations were taken from 90-day average high
concentrations from Prospective Ground Water studies; the RILP is a
function of aerobic soil metabolism and the soil-water partition
coefficient. The output of SCIGROW represents the concentrations that
might be expected in shallow unconfined aquifers under sandy soils,
which is representative of the ground water most vulnerable to pesticide
contamination likely to serve as a drinking water source. (**Ref. 2**)

An Estimated Drinking Water Concentration (EDWC) in surface water was
estimated using EFED's Tier I aquatic model FIRST (v1.1.0; 1/1/07).
FIRST (FQPA Index Reservoir Screening Tool) is a metamodel of PRZM and
EXAMS used as a screening tool to estimate pesticide concentrations
found in surface water used as drinking water. FIRST was developed by
making multiple runs of PRZM using varying sorption coefficients and
determining the concentration in the EXAMS index reservoir scenario
after a two-inch single storm event. (The Index Reservoir is a standard
water body used by the Office of Pesticide Programs to assess drinking
water exposure (Office of Pesticide Programs, 2002). It is based on a
real reservoir (albeit not currently in active use as a drinking water
supply), Shipman City Lake in Illinois, that is known to be vulnerable
to pesticide contamination.) The single runoff event moves a maximum of
8% of the applied pesticide into the reservoir. This amount can be
reduced by degradation or effects of binding to soil in the field.
Additionally, FIRST can account for spray drift and adjusts for the area
within a watershed that is planted with the modeled crop (Percent
Cropped Area). Spray drift (modeled as direct deposition of the
pesticide into the reservoir) is assumed to be 16% of the applied active
ingredient for aerial application, 6.3% for orchard air blast
application, and 6.4% for other ground spray application. Despite being
a single event model, FIRST can account for spray drift from multiple
applications. The default agricultural Percent Cropped Area (PCA) is
87%. The PRZM scenario used for FIRST development was among the most
vulnerable, and thus resulting surface water concentrations represent
the upper bound values on the concentrations that might be found in
drinking water from the use of a pesticide. (**Ref. 3 and 4**)

*Modeling Approach and Input Parameters*

Tier I modeling for the EDWC in surface water and groundwater from
fludioxonil use in a turf grass application pattern was conducted using
the maximum proposed application rate of 0.667 lbs a.i./A/application
applied three times at 14-day intervals for a total application rate of
2 lb ai/A/yr. Physical/chemical properties and environmental fate source
data (from submitted studies) were presented in Table 3. Input values
used for surface water modeling with FIRST are presented in Table 4.
Input values used for groundwater modeling with SCI-GROW2 are presented
in Table 5.

[]{.mark}

Input parameter values used in this assessment were selected from the
environmental fate data submitted by the registrant and in accordance
with US EPA-OPP EFED water model parameter selection guidelines,
*Guidance for Selecting Input Parameters in Modeling the Environmental
Fate and Transport of Pesticides*, Version II, February 28, 2002. d.,
Brit. Crop Protection Council, and The Royal Soc. of Chem. 1994).

Table 4. FIRST (v1.1.0) input parameter values for fludioxonil use on
turf grass.

  --------------------------------------------------------------------------
  PARAMETER (units)      VALUE(S)   SOURCE       COMMENT
  ---------------------- ---------- ------------ ---------------------------
  Application Rate (lb   3 apps of  Medallion    --
  a.i./A)                0.67 lb    Label        
                         ai/A 14                 
                         days apart              
                         or 6 apps               
                         of 0.333                
                         lb ai/A 7               
                         days                    
                         apart).                 

  Number of Applications 3 or 6     Medallion    --
                                    Label        

  Interval between       7 or 14    Medallion    --
  Applications (days)               Label        

  Percent Cropped Area   1.0        Medallion    A PCA is not used for turf
  (decimal)                         Label        grass.

  Soil Partition         991        MRID         Represents the lowest
  Coefficient (K~d~;                44382311     non-sand K~oc~ value among
  (mL/g) or K~OC~                                four values ranging from
  (mL/g~OC~))                                    991 to 2440 mL/g.

  Aerobic Soil           294.9      MRIDs        Represents the 90^th^
  Metabolism Half-life              43380513,    percentile of the upper
  (days)                            47169301,    confidence bound on the
                                    47169302a,   mean (249.3) of 8 half-life
                                    471693012,   values.
                                    471693013,   
                                    471693014    

  Wetted in?             No         Proposed     --
                                    label.       

  Depth of Incorporation 0          Proposed     --
  (inches)                          label.       

  Method of Application  Ground     Proposed     --
                         spray      label.       

  Solubility in Water @  1.5        Product      --
  20 ^O^C, (pH 7; in                Chemistry    
  mg/L or ppm)                                   

  Aerobic Aquatic        0 (stable) MRID         --
  Metabolism Half-life              47169304     
  (days)                                         

  Hydrolysis Half-life @ 0 (stable) MRID         --
  pH 7, 25 ^O^C (days)              43152502     

  Aquatic Photolysis     8.7        MRID         --
  Half-life @ pH 7                  43496302     
  (days)                                         
  --------------------------------------------------------------------------

^1^ Parameters are selected as per Guidance for Selecting Input
Parameters in Modeling the Environmental Fate and Transport of
Pesticides; Version I, February 28, 2002.

Table 5. SCI-GROW2 input parameter values for fludioxonil use on turf
grass.

+---------------------+---------------------+-------------+-----------+
| Model Input         | Input Value and     | Source      | Comments  |
| Parameter           | Unit                |             |           |
+---------------------+---------------------+-------------+-----------+
| **Aerobic Soil      | 230                 | MRIDs       | Median    |
| Metabolism          |                     | 43380513,   | value per |
| Half-life (days)**  |                     | 47169301,   | EFED      |
|                     |                     | 47169302a,  | guidance  |
|                     |                     | 471693012,  |           |
|                     |                     | 471693013,  |           |
|                     |                     | 471693014   |           |
+---------------------+---------------------+-------------+-----------+
| **Organic Carbon    | 1370                | MRID        | Input     |
| Normalized          |                     | 44382311    | value is  |
| Partition           |                     |             | the       |
| Coefficient K~oc~** |                     |             | median of |
|                     |                     |             | four      |
|                     |                     |             | values,   |
|                     |                     |             | per EFED  |
|                     |                     |             | guidance. |
+---------------------+---------------------+-------------+-----------+
| ##                  | 0.67 lb             | Label       | --        |
| ## Application Rate | ai/A/application    | (Medallion  |           |
|                     | (total of 2 lb      | Fungicide)  |           |
|                     | ai/A/yr)            |             |           |
+---------------------+---------------------+-------------+-----------+
| **Maximum No. of    | 3                   | Label       | --        |
| Applications/Year** |                     |             |           |
+---------------------+---------------------+-------------+-----------+

***Modeling Results***

Tier I surface water and groundwater modeling results for fludioxonil
for ground spray application to turf grass are presented in **Table 6.**
These values are recommended for use in the human health risk
assessment. Output values for surface water are not modified using the
percentage crop area (PCA) adjustment factor since the default for turf
grass is 1.0. Output values for groundwater are not adjusted for a PCA.

**Table 6. Maximum Tier I Estimated Drinking Water Concentrations
(EDWCs) for drinking water risk assessment based on ground spray
application of fludioxonil as used in a turf grass application
pattern.**

  ------------------- -------------------- --------------- ---------------
  **DRINKING WATER    **USE (rate          **MAXIMUM       
  SOURCE (MODEL       modeled)**           ESTIMATED       
  USED)**                                  DRINKING WATER  
                                           CONCENTRATION   
                                           (EDWC) ( ppb)** 

  Groundwater         Turf grass (0.67     Acute and       0.20
  (SCIGROW)           lbs. a.i./A/applic.  Chronic         
                      x 3 applic.; total                   
                      rate of 2 lb ai/A/yr                 
                      )                                    

  Surface water       Turf grass (0.67     Acute           81.3
  (FIRST)             lbs. a.i./A/applic.                  
                      x 3 applic.; total                   
                      rate of 2 lb ai/A/yr                 
                      )                                    

                      Turf grass (0.67     Chronic         37.4
                      lbs. a.i./A/applic.                  
                      x 3 applic.; total                   
                      rate of 2 lb ai/A/yr                 
                      )                                    
  ------------------- -------------------- --------------- ---------------

The SCIGROW concentration represents the groundwater concentration that
might be expected in shallow unconfined aquifers under sandy soils. The
output is used for both acute and chronic endpoints.

FIRST concentrations (ppb) represent untreated surface water
concentrations.

The one-in-10-year peak day concentration is used for acute endpoints
and the one-in-10-year annual average concentration is used for chronic
endpoints.

The estimated concentrations provided in this assessment are
conservative estimates of concentrations in drinking water. If dietary
risks require refinement, higher tiered crop-specific and
location-specific models and modeling scenarios can be used.

**Uncertainties and Data Gaps**

This assessment is based on available environmental fate data. There are
no significant data gaps in the environmental fate database submitted by
the registrant. Although data are not available for anaerobic aquatic
metabolism, the anaerobic phase of the anaerobic soil metabolism study
indicates that fludioxonil is stable under such conditions.

[]{.mark}

**References**

[]{.mark}

1.  Policy Establishing Current Versions of Exposure Models and
    Responsibility for Model Maintenance (11/06/2002)

2.  SCIGROW: Users Manual (11/01/2001, revised 08/23/2002)

3.  FIRST Users Manual (08/01/2001)

4.  FIRST: A Screening Model to Estimate Pesticide Concentrations in
    Drinking Water (05/01/2001)

5.  Guidance for Selecting Input Parameters in Modeling the
    Environmental Fate and Transport of Pesticides, Version II
    (02/28/2002)

6.  Use of the Index Reservoir and Percent Crop Area in EFED Drinking
    Water Assessments (12/01/1999)

[]{.mark}

> **APPENDIX A**

**TIER I SURFACE WATER MODELING OUTPUT FILES**

RUN No. 1 FOR fludioxonil ON turf grass \* INPUT VALUES \*

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE %CROPPED INCORP

ONE(MULT) INTERVAL Koc (PPM ) (%DRIFT) AREA (IN)

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

.667( 1.937) 3 14 991.0 1.5 GROUND( 6.4) 100.0 .0

FIELD AND RESERVOIR HALFLIFE VALUES (DAYS)

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS METABOLIC COMBINED

(FIELD) RAIN/RUNOFF (RESERVOIR) (RES.-EFF) (RESER.) (RESER.)

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

294.90 2 N/A 8.70- 1078.80 .00 1078.80

UNTREATED WATER CONC (MICROGRAMS/LITER (PPB)) Ver 1.1.0 JAN 1, 2007

\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\--

PEAK DAY (ACUTE) ANNUAL AVERAGE (CHRONIC)

CONCENTRATION CONCENTRATION

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81.307 37.351

**APPENDIX B**

**TIER I GROUND WATER MODELING OUTPUT FILES**

> SCIGROW

VERSION 2.3

ENVIRONMENTAL FATE AND EFFECTS DIVISION

OFFICE OF PESTICIDE PROGRAMS

U.S. ENVIRONMENTAL PROTECTION AGENCY

SCREENING MODEL

FOR AQUATIC PESTICIDE EXPOSURE

SciGrow version 2.3

chemical:fludioxonil

time is 3/10/2008 14:44: 4

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Application Number of Total Use Koc Soil Aerobic

rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

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0.667 3.0 2.001 13.70E+02 230.0

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groundwater screening cond (ppb) = 1.98E-01

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