Document ID: EPA-HQ-OPP-2005-0145-0014
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2006-12-20T05:00Z

Primary Evaluator	

 Douglas Dotson, Chemist, RAB2

	

Date: 9/22/2005  

Peer Reviewer	

 William Drew, Chemist, RAB2

	

Date: 10/7/2005 

This DER was originally prepared under contract by Dynamac Corporation
(1910 Sedwick Rd., Building 100, Suite B; Durham, NC 27713; submitted
1/14/2005).  The DER has been reviewed by the HED and revised to reflect
current OPP policies.

STUDY REPORT:

46145102 Chen, H. (2003) BAS 516 (BAS 510 F Plus BAS 500 F): Magnitude
of the Residue on Celery. Lab Project Number: IR-4 PR No. 08091. 
Unpublished study prepared by IR-4 Project Center for Minor Crop Pest
Management.  274 p. {OPPTS 860.1500}

EXECUTIVE SUMMARY:

Twelve celery fields trials were conducted during 2001, with eight field
trials in the US and four in Canada.  In each test, boscalid (70% WDG)
was applied to celery plants using ground equipment as two directed
foliar applications at 0.39-0.42 lb ai/A/application, for a total of
0.78-0.82 lb ai/A/season.  Applications were made during the vegetative
stage when plants were ~12-24" tall and the retreatment interval (RTI)
was 6-8 days.  The boscalid was tank mixed with the last two of four
foliar applications of the fungicide pyraclostrobin (20% WDG).  As the
pyraclostrobin data from these tests were previously reviewed
(46109102.der), it is not included in this report.  A single control (0
days after treatment (DAT) only) and duplicate treated samples of celery
plants were collected from each test at commercial maturity the same day
as the last treatment (0-DAT), 6-8 DAT, and 13-15 DAT.  Samples were
stored frozen from collection to analysis for 3.2-9.6 months, an
interval supported by available stability data.

The LC/MS/MS method (BASF Method Number D9908) used to determine
residues of boscalid in/on celery is adequate for data collection.  For
this method, residues are extracted with methanol:water:2 N HCl,
concentrated, and cleaned up by solvent partitioning and using a silica
gel SPE cartridge, prior to LC/MS/MS analysis.  The lowest limit of
method validation (LLMV) was 0.05 ppm.  Based on recovery data at the
LLMV, the LOQ and LOD were calculated to be 0.06 and 0.02 ppm,
respectively.

Residues of boscalid were 1.8-19.7 ppm in/on 24 celery samples harvested
immediately following (0-DAT) the last of two foliar applications. 
Boscalid residues were 0.3-11.0 ppm in/on 24 celery samples harvested
6-8 DAT and 0.2-9.8 ppm in/on 24 celery samples harvested 13-15 DAT. 
Average boscalid residues were 8.7 ppm from 0-DAT samples, 3.6 ppm from
7-DAT samples, and 2.3 ppm from 14-DAT samples.

STUDY/WAIVER ACCEPTABILITY/DEFICIENCIES/CLARIFICATIONS:

Under the conditions and parameters used in the study, the celery field
trial residue data are classified as scientifically acceptable.  The
acceptability of this study for regulatory purposes is addressed in the
forthcoming U.S. EPA  Residue Chemistry Summary Document (D322235).

COMPLIANCE:

Signed and dated GLP, quality assurance, and data confidentiality
statements were provided.  No deviations from regulatory requirements
were noted that would impact the study results or their interpretation.

A.	BACKGROUND INFORMATION

Boscalid is an anilide fungicide that inhibits mitochondrial
respiration, thereby inhibiting spore germination, germ tube elongation,
mycelial growth, and sporulation of pathogenic fungi on the leaf
surface.  Permanent tolerances have been established in 40 CFR §180.589
for residues of boscalid in/on numerous plant, animal, and rotational
crop commodities, ranging from 0.02 ppm in/on eggs to 35 ppm in/on dried
hops.  Tolerances have been established for two of the representative
commodities of the leafy vegetables crop group:  head lettuce at 6.5 ppm
and leaf lettuce at 11.0 ppm.  The current field trials were submitted
by IR-4 to support the use of boscalid on celery.  The proposed use rate
cited in the study was for two broadcast foliar applications of boscalid
(70% WDG) at 0.4 lb ai/A/application for a total of 0.8 lb ai/A/season,
with a RTI of 7 days and a 0-Day PHI.

The nomenclature and physicochemical properties of boscalid are
presented below in Tables A.1. and A.2.

TABLE A.1.	Nomenclature of Boscalid

Compound	

Common name	

Boscalid

Company experimental names	

BAS 510 F

IUPAC name	

2-chloro-N-(4'-chlorobiphenyl-2-yl)-nicotinamide

CAS name	

3-pyridinecorboxamide,2-chloro-N-(4'-chloro[1,1'-biphenyl]-2-yl

CAS #	

188425-85-6

End-use products/EP	

70% WDG (Endura( fungicide; EPA Reg. No. 7969-197)



TABLE A.2.  Physicochemical Properties for Boscalid

Parameter	

Value	

Reference

Melting point	

143.4-143.6(C  (TGAI); 142.8-143.8(C  (PAI)	

D278385, M. Nelson, 8/15/03

 

pH (23(C)	

5.5 (1% solution)

	

Density	

1.394g/cm3 (TGAI); 1.381g/cm3 (PAI)

	

Water solubility ( 20(C)	

4.64 mg/L (PAI)

	

Solvent solubility (g/100 mL at 20(C)	

PAI:  16-20 in acetone; 4-5 in acetonitrile; 4-5 in methanol; 6.7-8 in
ethylacetate; 20-25 in  dichloromethane; 2-2.5 in toluene; <1 in
1-octanol

	

Vapour pressure at 20(C	

7 x 10-9 hPa (PAI)

	

Dissociation constant (pKa)	

Does not dissociate in water.

	

Octanol/water partition coefficient at 21(C  Log(KOW)	

2.96 (PAI)

	

UV/visible absorption spectrum	

Not available

	TGAI: Technical Grade Active Ingredient

PAI: Pure Active Ingredient

B.	EXPERIMENTAL DESIGN

B.1.	Study Site Information

TABLE B.1.1	Trial Site Conditions.

Trial Identification 

(City, State, Year)	

Soil characteristics	

Meteorological data1

	

Type	

%OM	

pH	

CEC	

Overall total monthly rainfall range (inches)	

Overall average monthly temperature range ((C)

Gainesville, FL, 2001	

Sandy	

NA = Not Applicable	

8.8-9.8	

Not reported = NR

Gainesville, FL, 2001	

Sandy	

NA	

8.8-9.8	

NR

Holtville, CA, 2001	

Silty Clay Loam	

NA	

NR	

NR

Visalia, CA, 2001	

Loam	

NA	

NR	

NR

Brooks, OR, 2001	

Silt Loam	

NA	

NR	

NR

Celeryville, OH, 2001	

Muck	

NA	

NR	

NR

Salinas, CA, 2001	

Loam	

NA	

NR	

NR

Salinas, CA, 2001	

Loam	

NA	

NR	

NR

Quebec, Canada, 2001	

Muck	

NA	

NR	

NR

Quebec, Canada, 2001	

Muck	

NA	

dry in July and early August	

excess temperature in July and early August 1

Ontario, Canada, 2001	

Silt Loam	

NA	

NR	

early October frost 1

Ontario, Canada, 2001	

Silt Loam	

NA	

dry in August	

early October frost 1

1	Detailed meteorological data were not provided.

Weather conditions were reported to be normal, with the following
exceptions: (i) conditions were wetter than normal in June and July at
the two FL locations; (ii) conditions were drier and warmer than normal
at one Quebec location in July and early August, and drier in August at
one Ontario location; and (iii) early October frost was reported from
both Ontario locations.  No further details were provided.  No unusual
conditions that would affect the integrity of the study were reported. 
Rainfall was supplemented with irrigation as needed. 

Twelve celery field trials were conducted during 2001, eight in the US
and four in Canada.  In each test, boscalid (70% WDG) was applied to
celery plants using ground equipment as two directed foliar applications
(Table B.1.2), with a RTI of 6-8 days.  Applications were made during
the vegetative stage when plants were ~12-24" tall, at approximately
commercial maturity.  The application rate was 0.39-0.42 lb
ai/A/application, for a total of 0.78-0.82 lb ai/A/season.  

Each field test also included applications of the fungicide
pyraclostrobin (BAS 500 F; 20% WDG) as four broadcast foliar
applications at ~0.2 lb ai/A for a total of 0.8 lb ai/A/season, at  RTIs
of ~7 days.  The final two pyraclostrobin applications were tank mixed
with the two boscalid applications.  Residue data for pyraclostrobin and
its regulated metabolite were included in the submission; however, these
data are not included in this report as the data were previously
reviewed (46109102.der, M. Xue, 7/22/04).

TABLE B.1.2.  Study Use Pattern on Celery.

Location (City, State), Year	

EP 1	

Method 2; Timing 3	

Volume (gal/A)	

Single Rate

(lb ai/A) 4 	

No. of Appl.	

RTI (days)	

Total Rate

(lb ai/A)4	

Tank Mix Adjuvants

Gainesville, FL, 2001	

70% WDG	

Foliar directed; vegetative 	

36	

0.41	

2	

8	

0.82	

None

Gainesville, FL, 2001	

70% WDG	

Foliar directed; vegetative 	

35, 36	

0.40, 0.41	

2	

8	

0.81	

None

Holtville, CA, 2001	

70% WDG	

Foliar directed; vegetative 	

41, 43	

0.40, 0.41	

2	

7	

0.81	

None

Visalia, CA, 2001	

70% WDG	

Foliar directed; vegetative 	

49	

0.41	

2	

7	

0.82	

None

Brooks, OR, 2001	

70% WDG	

Foliar directed; vegetative 	

42, 43	

0.40, 0.41	

2	

8	

0.81	

None

Celeryville, OH, 2001	

70% WDG	

Foliar directed; vegetative 	

53, 54	

0.39, 0.40	

2	

8	

0.79	

None

Salinas, CA, 2001	

70% WDG	

Foliar directed; vegetative 	

63, 87	

0.41, 0.42	

2	

6	

0.83	

None

Salinas, CA, 2001	

70% WDG	

Foliar directed; vegetative 	

63, 66	

0.41, 0.42	

2	

7	

0.83	

None

Napierville, Quebec, Canada, 2001	

70% WDG	

Foliar directed; vegetative 	

48, 52	

0.38, 0.40	

2	

7	

0.78	

None

Napierville, Quebec, Canada, 2001	

70% WDG	

Foliar directed; vegetative 	

50, 51	

0.39, 0.40	

2	

7	

0.79	

None

Ontario, Canada, 2001	

70% WDG	

Foliar directed; vegetative 	

37	

0.40	

2	

6	

0.80	

None

Ontario, Canada, 2001	

70% WDG	

Foliar directed; vegetative 	

37, 38	

0.40, 0.41	

2	

6	

0.81	

None

1	EP = End-use Product.

2	The applications were made using ground equipment.

3	Applications were made when plants were approximately at commercial
maturity.

4	The target rate for the celery field trials was 0.40 lb
ai/A/application and 0.80 lb ai/A/season. 



TABLE B.1.3.	Trial Numbers and Geographical Locations.

NAFTA Growing Region 1	

 Celery

	

Submitted	

Requested

Canada	

US

1	

--	

NA	

--

2	

--	

NA	

--

3	

2	

NA	

2

4	

--	

NA	

--

5	

1	

NA	

1

5A 2	

2 2	

NA	

NA

5B 2	

2 2	

NA	

NA

6	

--	

NA	

--

7	

--	

NA	

--

8	

--	

NA	

--

9	

--	

NA	

--

10	

4	

NA	

5

11	

--	

NA	

--

12	

1	

NA	

--

13	

--	

NA	

--

Total	

12	

NA	

8

1	Regions 14-21 and 1A, and 7A were not included as the proposed use is
for the US only. 

2	Although the proposed use is for the US, additional tests were
conducted in Regions 5A (Ontario) and 5B (Quebec).

NA = not applicable.

B.2.	Sample Handling and Preparation

Celery plants were harvested at commercial maturity, the same day as the
last application (0-DAT), 6-8 DAT, and 13-15 DAT from all tests.  A
single control (0 DAT only) and duplicate treated celery samples (12
whole plants each) were collected from each test and placed in frozen
storage at the test facility within 7 hours.  Samples were stored frozen
for 0-132 days, then shipped frozen by ACDS freezer truck, FedEx, or
Airborne Express to the analytical laboratory, BASF Agro Research, RTP,
NC, and stored frozen (<-10( C) prior to analysis.  Samples were stored
frozen from collection to analysis for up to 9.6 months.

B.3.	Analytical Methodology

Residues of boscalid were determined using an LC/MS/MS method (BASF
Method Number D9908).  Method D9908 was validated in conjunction with a
previous boscalid petition (DP Barcode D278385, M. Nelson, 8/15/03) and
deemed acceptable for data collection.  A brief description of the
method follows.  Residues are extracted with methanol:water:2 N HCl
(70:25:5, v/v/v), concentrated, and partitioned into cyclohexane. 
Residues were then concentrated and cleaned up using a silica gel solid
phase extraction cartridge eluted with 4% ethyl acetate in methylene
chloride.  Residues are analyzed by LC/MS/MS using the positive
ionization mode monitoring ion transitions from m/z 343 to 307. 
Quantitation is obtained using an external calibration curve with
boscalid.  The LLMV for boscalid residues is 0.05 ppm in/on celery. 
Using the recovery data from the lowest fortification level, a LOD of
0.02  ppm and a LOQ of 0.06 ppm were calculated based on a method
described in Roy-Keith Smith’s Handbook of Environmental Analysis, 4th
Ed.

In conjugation with the current field trials, control samples of celery
were fortified with boscalid at 0.05-20 ppm and analyzed concurrently
with the field samples.

C.	RESULTS AND DISCUSSION

The number and geographic representation of the celery field trials are
adequate.  Eight field trials were conducted in the U.S. in  Regions 3
(two tests), 5 (one test), 10 (four tests), and 12 (one test).  Four
field trials were also conducted in Canada in Regions 5A (2 tests) and
5B (2 tests). 

The LC/MS/MS method (BASF Method Number D9908) used to determine
residues of boscalid in/on celery is adequate for data collection. 
Average concurrent recoveries were 73% with a standard deviation of 12%
for boscalid (Table C.1).  Apparent residues of boscalid were <LOQ in/on
all control samples.  Based on the LLMV, the LOQ and LOD were calculated
to be 0.06 and 0.02 ppm, respectively.  Adequate sample calculations and
chromatograms were provided.

Samples were stored frozen from collection to analysis for 3.2-9.6
months (Table C.2).  Storage stability data are available on
representative plant commodities indicating that boscalid is stable in
frozen storage for at least 12 months (D278385, M. Nelson, 8/15/03). 
These data will support the current celery field trials.

TABLE C.1	Summary of Concurrent Recoveries of Boscalid from Celery using
LC/MS/MS Method D9908.

Analyte	

Celery Matrix	

Spiking Level

(mg/kg)	

Sample size	

Recoveries (%)	

Mean Recovery ± SD

Boscalid

	

Stems and leaves	

0.05	

13	

41-99 (5) 1	

73 ± 12

1.0	

8	

62-93 (1) 1

	

2.0	

1	

88

	

10	

3	

70-85

	

20	

2	

72, 76

	1	The number of recoveries outside the 70-120% range is in parentheses.



TABLE C.2	Summary of Freezer Storage Conditions

Celery Matrix	

Storage Temp. ((C)	

Actual Storage Duration (months) 1		

Limit of Demonstrated Storage Stability (months) 2

Leaves	

< -10	

3.2-9.6	

12

1	Extracts were stored frozen for 0-3 days prior to analysis.

2	Storage stability data are available indicating that boscalid is
stable in frozen plant commodities for at least 12 months (D278385, M.
Nelson, 8/15/03).

Residues of boscalid were 1.8-19.7 ppm in/on 24 celery samples harvested
immediately following (0-DAT) the last of two foliar applications of the
70% WDG totaling 0.78-0.83 lb/A/season (Table C.3).  Boscalid residues
were 0.3-11.0 ppm in/on 24 celery samples harvested 6-8 DAT and 0.2-9.8
ppm in/on 24 celery samples harvested 13-15 DAT.  Average boscalid
residues were 8.7 ppm from 0-DAT samples, 3.6 ppm from 7-DAT samples,
and 2.3 ppm (HAFT = 9.3 ppm) from 14 DAT samples (Table C.4).  In all
field trials except one (i.e., the one performed in Holtwell, CA)
residues decreased with an increase in PHI.

Common cultural practices were used to maintain plants, and the weather
conditions and the maintenance chemicals and fertilizer used in the
study did not have a notable impact on the residue data.  In addition,
the application volume has minimal or no impact on residue levels.

TABLE C.3.	Residue Data from Celery Field Trials with a 70% WDG
Formulation of Boscalid.

Trial ID 

(City, State, Year)	

EPA

Region	

Celery Variety	

Celery Matrix	

Total Rate

(lb ai/A)	

PHI (days) 1	

Boscalid Residues (ppm)

Gainesville, FL, 2001	

3	

June Bell 1622	

Stems and Leaves	

0.82	

0	

12.5, 13.4

	

7	

11.0, 8.6

	

14	

3.3, 2.7

Gainesville, FL, 2001	

3	

June Bell 1622	

Stems and Leaves	

0.81	

0	

15.6, 18.3

	

7	

4.4, 4.5

	

14	

3.1, 3.1

Holtville, CA, 2001	

10	

Conquistador	

Stems and Leaves	

0.81	

0	

9.7, 9.7

	

7	

8.3, 7.6

	

14	

9.8, 8.8

Visalia, CA, 2001	

10	

Conquistador	

Stems and Leaves	

0.82	

0	

8.3, 7.6

	

7	

5.5, 5.0

	

14	

4.3, 5.0

Brooks, OR, 2001	

12	

Picador	

Stems and Leaves	

0.81	

0	

4.4, 5.6

	

7	

3.3, 3.7

	

14	

0.88, 2.6 (1.7)2, 

2.5, 2.3 (2.4)2

Celeryville, OH, 2001	

5	

Ventura	

Stems and Leaves	

0.79	

0	

8.6, 8.1

	

8	

3.8, 4.0

	

14	

0.72, 0.78

Salinas, CA, 2001	

10	

Conquistador	

Stems and Leaves	

0.83	

0	

2.7, 2.6

	

7	

0.88, 0.70

	

14	

0.40, 0.33

Salinas, CA, 2001	

10	

Conquistador	

Stems and Leaves	

0.83	

0	

1.9, 1.8

	

6	

0.79, 0.73

	

13	

0.35, 0.47

Quebec, Canada, 2001	

5B	

Calmario	

Stems and Leaves	

0.78	

0	

2.0, 2.0

	

8	

0.39, 0.32

	

15	

0.16, 0.23

Quebec, Canada, 2001	

5B	

Calmario	

Stems and Leaves	

0.79	

0	

6.5, 6.7

	

7	

1.0, 1.9, 1.9 (1.9)2

	

14	

0.66, 0.77, 0.61 (0.68)2, 0.34, 0.34, 0.12 (0.27)2

Ontario, Canada, 2001	

5A	

Florida 683	

Stems and Leaves	

0.80	

0	

19.7, 18.4

	

7	

3.5, 2.3

	

14	

1.3, 1.4

Ontario, Canada, 2001	

5A	

Florida 683	

Stems and Leaves	

0.81	

0	

12.6, 10.7

	

7	

2.7, 2.5

	

14	

1.5, 1.2

1	The current PHI for lettuce is 14 days; the proposed PHI for celery is
0 days.

2	Values in italics represent multiple analyses of the sample; the
average (in parentheses) was used is subsequent calculations.

TABLE C.4.	Summary of Residue Data for Celery from Crop Field Trials
Using a 70% WDG Formulation of Boscalid.

Commodity	

Total Rate

(lb a.i./A) 	

PHI (days) 1	

Boscalid Residue Levels (ppm)

	

n	

Min.	

Max.	

HAFT 2	

Median (STMdR3)	

Mean (STMR3)	

Std. Dev.

Celery	

0.78-0.83	

0	

24	

1.8	

19.7	

19.1	

8.2	

8.7	

5.5

6-8	

24	

0.3	

11.0	

9.8	

3.4	

3.6	

2.9

13-15	

24	

0.2	

9.8	

9.3	

1.4	

2.3	

2.6

1	The current PHI for lettuce is 14 days; the proposed PHI for celery is
0 days.

2 	HAFT = Highest Average Field Trial. 

3	STMdR = Supervised Trial Median Residue; STMR = Supervised Trial Mean
Residue.

D.	CONCLUSION

The celery field trial data are adequate and reflect the use of up to
two foliar directed applications of a 70% WDG formulation of boscalid
totaling ~0.8 lb ai/A/season.  The data would support a PHI of 0 days, 7
days, or 14 days.  Maximum boscalid residues were 19.7 ppm from 0-day
PHI samples, 11.0 ppm from 7-day PHI samples, and 9.8 ppm from 14-day
PHI samples.

E.	REFERENCES

D278385, PP#0F06313, BAS 510 F (Common Name: Boscalid), New Fungicide
Active Ingredient. Residue Chemistry Summary Document, M. Nelson,
8/15/03

F.	DOCUMENT TRACKING

Petition Number: 1F6313

DP Barcode: D316092

PC Code: 128008

Boscalid/7969-197/PC Code 128008/BASF Corporation/7969

DACO 7.4.1/OPPTS 860.1500/OECD IIA 6.3.1, 6.3.2, 6.3.3 and IIIA 8.3.1,
8.3.2, 8.3.3

Crop Field Trial - Celery

((((( PAGE  9 ((((( NUMPAGES  9 

DP Barcode D316092/MRID No. 46145102