Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF CHEMICAL SAFETY AND

POLLUTION PREVENTION

MEMORANDUM

Date: 28-July-2010

Subject: Spirodiclofen in/on the Bushberry Subgroup 13-07B. Summary of Analytical 

Chemistry and Residue Data.

PC Code: 124871 DP Barcode: D371643

Decision No.: 421907 Registration No.: 264-831

Petition No.: 9E7632 Regulatory Action: Section 3 

Risk Assessment Type: not applicable Case No.: 7443

TXR No.: not applicable CAS No.: 148477-71-8

MRID Nos: 47886201 40 CFR: 180.608

From: Tom Bloem, Chemist

Risk Assessment Branch I, Health Effects Division (RABI/HED; 7509C)

Through: George F. Kramer, Ph.D., Senior Chemist

HED/RABI (7509P)

To: Barbara Madden/Laura Nollen (RM 05)

Registration Division (RD; 7505P) 

Interregional Research Project Number 4 (IR-4; Princeton, NJ) proposed a Section 3 registration 

for application of spirodiclofen (3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4.5]dec-3-en-4-yl 2,2-

dimethylbutanoate; see attachment 1 for structure) to the bushberry subgroup 13-07B for the 

control of blueberry budmite. In conjunction with the request, the petitioner proposed the 

establishment of a 4.0 ppm tolerance for residues of spirodiclofen per se in/on the bushberry

subgroup 13-07B. 
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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Executive Summary

Background: Spirodiclofen is a tetronic acid with acaricidal action (group 23). It acts by

interfering with mite development and controls such pests as Panonychus spp., Phyllocoptruta

spp., Brevipalpus spp., and Aculus and Tetranychus species. The petitioner stated that 

spirodiclofen is active by contact to mite eggs, all nymphal stages, and adult females (adult males 

are not effected). Spirodiclofen is currently registered for application to citrus fruit, grape, pome 

fruit, stone fruit, tree nuts, avocado, black sapote, canistel, mamey sapote, mango, papaya, 

sapodilla, star apple, and hops with tolerances for residues of spirodiclofen per se of 0.10-30 

ppm; milk and ruminant meat, meat byproducts, and fat tolerance for the combined residues of 

spirodiclofen and BAJ 2510 are also established (0.02-0.1 ppm). 

Proposed Application Scenarios: The petitioner provided proposed use directions for 

application of Envidor® 2 SC Miticide (suspension-concentrate; 2 lbs ai/gallon; EPA Reg. No. 

264-831) to the bushberry subgroup 13-07B for the control of blueberry budmite (see Table 1 for 

summary). Application through irrigation equipment and in enclosed structures is prohibited. 

Although the label does not indicate that adjuvants (e. g.; crop-oil concentrate, nonionic

surfactant, methylated seed oil) should be added to the spray solution, it does not prohibit the 

inclusion of adjuvants. Since the field trial data submitted in support of the proposed action did 

not include adjuvants, HED requests a revised Section B prohibiting the addition of adjuvants to 

the spray solution. 

Table 1: Summary of Proposed Application Scenarios.

Applic. Type Max. Single Applic. 

Rate (lb ai/acre)

Max. No. Applic. 

per Season

PHI1

(days) Comments

bushberry subgroup 13-07B (aronia berry, highbush blueberry, lowbush blueberry, Buffalo currant, Chilean guava, 

black currant, red currant, elderberry, European barberry, gooseberry, highbush cranberry, honeysuckle, huckleberry, jostaberry, 

juneberry, lingonberry, native Currant, salal, and sea buckthorn)

foliar spray 0.25-0.28 1 7

●Minimum spray volume of 30 gallons per acre.

●Maximum seasonal application rate - 0.28 lb ai/acre.

1

 PHI = preharvest interval.

Nature of the Residue - Primary Crops: Based on the results of previously submitted apple and 

grape processing studies and citrus, grape, and apple metabolism studies (D285249, T. Bloem, 

18-Apr-2005; D341847, T. Bloem, 25-Oct-2007; D359773, T. Bloem, 24-Jun-2009), HED 

concluded the following: (1) citrus fruit, pome fruit, stone fruit, and tree nut - the residue of 

concern for risk assessment and tolerance enforcement is spirodiclofen per se and (2) grape - the 

residue of concern for tolerance enforcement is spirodiclofen per se and residues of concern for 

risk assessment are spirodiclofen and BAJ 2510. Since the grape processing study demonstrated 

degradation of spirodiclofen to BAJ 2510, HED is requesting that the petitioner submit an orange 

processing study monitoring for residues of spirodiclofen, BAJ 2510, 3-OH-enol, and 4-OH-enol

(apple processing study did not demonstrate this degradation). Pending the submission of the 

orange processing data, human-health risk assessments should assume default processing factors 

for all processed commodities excluding the processed commodities for apple and grape.

HED is willing to translate these conclusions to the proposed crops. Therefore, the residue of 

concern in the requested crops is spirodiclofen per se. The following is a summary of the 

currently-available plant metabolism data. 
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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The apple, citrus, and grape metabolism studies indicate that the metabolism of spirodiclofen in 

fruit crops involves the following steps: cleavage of the ester linkage to form BAJ 2510;

hydroxylation of BAJ 2510 on the cyclohexyl ring to form 3-OH-enol and 4-OH-enol 

metabolites; and cleavage of the enol ring structure to form 2,4-dichloro-mandelic acidcyclohexylester, which undergoes hydroxylation/conjugation and further degradation to yield 2,4-

dichloro-mandelic acid (free and conjugated). The grape processing study indicates that residues 

of spirodiclofen degrade to BAJ 2510 during processing of grapes to juice, juice concentrate, 

jelly, and raisin (apple processing study did not demonstrate this). 

The majority of the residues in/on fruit were surface residues or were associated with the peel 

with nearly all these being comprised of parent compound. Overall, spirodiclofen accounted for 

34-99% of the total radioactive residues (TRR). Minor amounts of the following compounds 

were also identified: BAJ 2510 (≤2% TRR), 3-OH-enol (≤3% TRR), 4-OH-enol (<1% TRR), 

2,4-dichloro-mandelic acid-cyclohexylester compounds (free and conjugated; ≤9% TRR), and 

2,4-dichloro-mandelic acid (free and conjugate; ≤12% TRR).

Magnitude of the Residue - Primary Crops: In support of the proposed registration, six 

lowbush (North American Free Trade Agreement (NAFTA) growing zones 1 (n=4) and 5 (n=2)) 

and six highbush (n=6; NAFTA growing zones 2 (n=3), 5 (n=1), and 12 (n=2)) blueberry field 

trials were submitted. Provided a revised Section B is submitted, the application scenario 

employed in the field trials supports the proposed application scenario and resulted in 

spirodiclofen per se residues in/on highbush and lowbush blueberry of 0.362-1.069 ppm and 

0.100-2.333 ppm, respectively. Based on these data, the Agency's tolerance calculator 

recommended for highbush and lowbush blueberry tolerances for residues of spirodiclofen per se

of 1.4 ppm and 3.5 ppm, respectively. 

The representative commodity for the bushberry subgroup 13-07B is highbush blueberry with 

lowbush blueberry included in the subgroup. HED notes that additional trials in zones 1 (n=1) 

and 5 (n=2) are needed to fulfill the geographical distribution specified in OPPTS 860.1500 for 

highbush blueberry. Since the petitioner submitted six lowbush blueberry field trials and the data 

for these trials indicates that residues are higher in/on lowbush blueberry as compared to 

highbush blueberry, HED concludes that additional data are unnecessary. Based on the 

submitted data, HED concludes that a tolerance of 3.5 ppm for residues of spirodiclofen per se

in/on the bushberry subgroup 13-07B is appropriate. A revised Section F is requested. 

Analytical Enforcement Method: HED determined that the Bayer analytical method 109351 

was appropriate for enforcement of the hop, citrus, grape, pome fruit, stone fruit, and tree nut 

tolerances and forwarded this method to Food and Drug Administration (FDA) for inclusion in 

the Pesticide Analytical Manual (PAM; D368434, T. Bloem, 23-Sep-2009). Based on the 

similarities of the tolerance enforcement and the adequately validated data collection methods, 

HED concludes that the current enforcement method is appropriate for enforcement of the 

tolerances recommended as part of the current petition. 

FDA Multiresidue Methods: Spirodiclofen and BAJ 2510 were screened through the FDA 

MRM protocols. Since both spirodiclofen and BAJ 2510 are not N-methylcarbamates, naturally

fluorescent, acids, phenols, or substituted ureas, testing through protocols A, B, and G is 

unnecessary. Protocol C modules DG1 and DG10 gave acceptable results for BAJ 2510 and 

spirodiclofen, respectively (both are GC/ECD systems). Using fortified orange samples, 
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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acceptable recoveries of spirodiclofen were attained through Protocols D (80-103%) and E (54-

77%). Using fortified ground beef samples, unacceptable recoveries of spirodiclofen were 

attained through protocol F (16-30%). BAJ 2510 was not recovered through the florisil clean-up 

column, and therefore, gave unacceptable recoveries for Protocol D (fortified orange samples) 

and F (fortified ground beef samples). Since BAJ 2510 was not recovered through Protocol D, 

Protocol E was not tested. These data have been forwarded to FDA (D308565, T. Bloem, 29-

Sep-2004).

Nature/Magnitude of the Residue - Livestock: Based on the revised Table 1 feedstuffs 

(OPPTS 860.1000), none of the proposed crops have feed commodities; therefore a 

discussion concerning the nature/magnitude of the residue in livestock is unnecessary. 

Nature/Magnitude of the Residue - Rotational Crops: Since all of the requested crops are 

perennials, a discussion concerning the nature/magnitude of the residue in rotational crops is 

unnecessary. 

Recommendations: Provided revised Sections B and F are submitted, HED concludes that the 

residue chemistry database supports an unconditional registration for application of spirodiclofen 

to the bushberry subgroup 13-07B and establishment of the following permanent tolerance for 

residues of only spirodiclofen (180.608(a)(1)): Bushberry subgroup 13-07B - 3.5 ppm. A 

human-health risk assessment will be prepared as a separate document. 

In accordance with the most recent guidance concerning tolerance expressions, HED 

recommends that the tolerance expression for 180.608(a)(1) and 180.6(a)(2) be changed as 

indicated below. HED notes that this alteration in the tolerance expression does not necessitate a 

change in the currently established or recommended tolerance levels. A revised Section F 

specifying the new tolerance expression, the currently established commodity/tolerance levels,

and the HED-recommended bushberry subgroup 13-07B tolerance should be submitted. 

180.608(a)(1): Tolerances are established for residues of spirodiclofen, including its metabolites and 

degradates, in or on the commodities listed below. Compliance with the following tolerance levels is 

to be determined by measuring only spirodiclofen (3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4.5]dec-3-

en-4-yl 2,2-dimethylbutanoate.

180.608(a)(2): Tolerances are established for residues of spirodiclofen, including its metabolites and 

degradates, in or on the commodities listed below. Compliance with the following tolerance levels is 

to be determined by measuring only spirodiclofen (3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4.5]dec-3-

en-4-yl 2,2-dimethylbutanoate) and its metabolite 3-(2,4-dichlorophenyl)-4-hydroxy-1-oxaspiro[4,5]

dec-3-en-2-one.

Summary of Residue Chemistry Deficiencies:

Revised Section B

Revised Section F
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Detailed Considerations

Background

Spirodiclofen is a tetronic acid with acaricidal action (group 23). It acts by interfering with mite 

development, and controls such pests as Panonychus spp., Phyllocoptruta spp., Brevipalpus spp., 

and Aculus and Tetranychus species. The petitioner stated that spirodiclofen is active by contact 

to mite eggs, all nymphal stages, and adult females (adult males are not effected). Tables 2 and 3

are summaries of spirodiclofen nomenclature and physical chemical properties, respectively.

Table 2: Nomenclature.

Spirodiclofen

O

O

Cl

Cl

O

O H3C

H3C

H3C

Common name Spirodiclofen

Company experimental name BAJ2740

IUPAC name 3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4,5]dec-3-en-4-yl 2,2-dimethylbutyrate

CAS name 3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4,5]dec-3-en-4-yl 2,2-dimethylbutanoate

CAS registry number 148477-71-8

End-use product (EP) 2 lb/gal FlC (ENVIDOR®2 SC Miticide; EPA Reg. No. 264-831)

Table 3: Physicochemical Properties of Spirodiclofen.

Melting point 94.8oC

D315459, S. Mathur, 

20-Apr-2005

pH 4.2

Density (20oC) 1.29 g/cm3

Water solubility (20oC at pH 4) 50μg/L

Solvent solubility (g/L at 20°C)

n-heptane 

xylene 

dichloromethane 

2-propanol

1-octanol

polyethylene glycol

acetone

ethyl acetate

acetonitrile

dimethylsulfoxide

20

>250

>250

47

44

24

>250

>250

>250

75

Vapor pressure (20oC) 3 x 10-7Pa

Dissociation constant, pKa

Not determinable due to the instability in 

aqueous solutions at >pH 4

Log(KOW) at pH 4 and 20oC 5.83

UV/visible absorption spectrum λmax = 201 nm: Not expected to absorb UV 

at λ >350 nm
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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860.1200 Directions for Use

The petitioner provided proposed use directions for application of Envidor® 2 SC Miticide 

(suspension-concentrate; 2 lbs ai/gallon; EPA Reg. No. 264-831) to the bushberry subgroup 13-

07B for the control of blueberry budmite (see Table 1 for summary). Application through 

irrigation equipment and in enclosed structures is prohibited. Although the label does not 

indicate that adjuvants (e. g.; crop-oil concentrate, nonionic surfactant, methylated seed oil) 

should be added to the spray solution, it does not prohibit the inclusion of adjuvants. Since the 

field trial data submitted in support of the proposed action did not include adjuvants, HED 

requests a revised Section B prohibiting the addition of adjuvants to the spray solution. 

860.1300 Nature of the Residue - Plants

Based on the results of previously submitted apple and grape processing studies and citrus, grape, 

and apple metabolism studies (D285249, T. Bloem, 18-Apr-2005; D341847, T. Bloem, 25-Oct2007; D359773, T. Bloem, 24-Jun-2009), HED concluded the residue of concern in the proposed

crops is spirodiclofen per se (see Executive Summary for more information). 

860.1300 Nature of the Residue - Livestock

Based on the revised Table 1 feedstuffs (OPPTS 860.1000), none of the proposed crops have 

feed commodities; therefore a discussion concerning the nature of the residue in livestock is 

unnecessary. 

860.1340 Residue Analytical Methods

Tolerance Enforcement: HED forwarded Bayer analytical method 109351 to FDA for inclusion 

in the PAM (D368434, T. Bloem, 23-Sep-2009). Briefly, fruit samples are extracted with 

acetonitrile:water (2:1; v:v) containing a small amount of aqueous 20% cysteine hydrochloride, 

filtered, and acidified with HCl. The extract is subjected to clean up on an ENVI-carb cartridge 

preconditioned with DCM, methanol, and water with residues eluted with DCM under vacuum. 

The resulting eluent is concentrated to dryness and reconstituted in ACN and water for analysis 

by LC/MS/MS. The LOQ was reported to be 0.01 ppm (LOD ranged from 0.001-0.006 ppm). 

Based on the similarities of the tolerance enforcement and the adequately validated data 

collection methods, HED concludes that the current enforcement method is appropriate for 

enforcement of the tolerances recommended as part of the current petition. 

Data Collection: The blueberry field trial samples were analyzed for residues of spirodiclofen 

per se using an adequately validated liquid chromatograph/mass spectrometer/mass spectrometer 

(LC/MS/MS) method. Briefly, homogenized samples were extracted by blending with 

acetonitrile:water (2:1; v:v) and 20% cysteine hydrochloride. Samples were filtered, acidified 

with 1.2N HCl, and partitioned with dichloromethane (DCM) prior to analysis by LC/MS/MS. 

The submitted method validation and concurrent recovery data were adequate. Based on the 

LLMV, the LOQ was 0.0102 ppm. The study indicated that the statistically determined LOQ and 

LOD were 0.1644 ppm and 0.0548 ppm, respectively (standard deviation at LLMV multiplied by

the one-tailed 99% t-stat). However, HED found an error in the calculation and recalculated the 

LOQ and LOD as 0.008 ppm and 0.003 ppm respectively (calculation used a value of 0.102 ppm 

rather than 0.0102 ppm). 
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860.1360 Multiresidue Methods

Spirodiclofen and BAJ 2510 were screened through the FDA MRM protocols. Since both 

spirodiclofen and BAJ 2510 are not N-methylcarbamates, naturally fluorescent, acids, phenols, or 

substituted ureas, testing through protocols A, B, and G is unnecessary. Protocol C modules 

DG1 and DG10 gave acceptable results for BAJ 2510 and spirodiclofen, respectively (both are 

GC/ECD systems). Using fortified orange samples, acceptable recoveries of spirodiclofen were 

attained through Protocols D (80-103%) and E (54-77%). Using fortified ground beef samples, 

unacceptable recoveries of spirodiclofen were attained through protocol F (16-30%). BAJ 2510 

was not recovered through the florisil clean-up column, and therefore, gave unacceptable 

recoveries for Protocol D (fortified orange samples) and F (fortified ground beef samples). Since 

BAJ 2510 was not recovered through Protocol D, Protocol E was not tested. These data have 

been forwarded to FDA (D308565, T. Bloem, 29-Sep-2004).

860.1380 Storage Stability

The blueberry samples from the field trials were stored frozen for up to 327 days prior to analysis. 

As part of the current study, the petitioner submitted storage stability which indicate that residues 

of spirodiclofen per se are stable in/on blueberry when stored frozen for 352 days. HED notes 

that these data did not include a zero day analysis as requested in the OPPTS 860.1380 guidelines. 

The petitioner previously submitted storage stability data which indicated that residues of 

spirodiclofen per se are stable when stored frozen for the following crop/intervals (D285249, T. 

Bloem, 18-Apr-2005): 391 days (grape), 231 days (raisin), 226 days (grape juice concentrate), 

231 days (apple juice concentrate), 231 days (dried apple), 391 days (peaches), 306 days (prunes), 

410 days (almond nutmeat), and 305 days (almond hulls). The almond hull data indicated a 26% 

reduction in residues for samples stored 410 days. These data support the storage intervals and 

conditions for the blueberry samples collected as part of the current study.

860.1480 Meat, Milk, Poultry, and Eggs

Based on the revised Table 1 feedstuffs (OPPTS 860.1000), none of the proposed crops have 

feed commodities; therefore a discussion concerning the magnitude of the residue in livestock is 

unnecessary. 

860.1500 Crop Field Trials

47886201.der.doc

In support of the proposed registration, six lowbush (NAFTA growing zones 1 (n=4) and 5 

(n=2)) and six highbush (n=6; NAFTA growing zones 2 (n=3), 5 (n=1), and 12 (n=2)) blueberry

field trials were submitted. Provided a revised Section B is submitted, the application scenario 

employed in the field trials supports the proposed application scenario and resulted in 

spirodiclofen per se residues in/on highbush and lowbush blueberry of 0.362-1.069 ppm and 

0.100-2.333 ppm, respectively (see below for summary). Based on these data, the Agency's 

tolerance calculator recommended for highbush and lowbush blueberry tolerances for residues of 

spirodiclofen per se of 1.4 ppm and 3.5 ppm, respectively (see attachment 3). 

The representative commodity for the bushberry subgroup 13-07B is highbush blueberry with 

lowbush blueberry included in the subgroup. HED notes that additional trials in zones 1 (n=1) 

and 5 (n=2) are needed to fulfill the geographical distribution specified in OPPTS 860.1500 for 
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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highbush blueberry. Since the petitioner submitted six lowbush blueberry field trials and the data 

for these trials indicates that residues are higher in/on lowbush blueberry as compared to 

highbush blueberry, HED concludes that additional data are unnecessary. Based on the 

submitted data, HED concludes that a tolerance of 3.5 ppm for residues of spirodiclofen per se

in/on the bushberry subgroup 13-07B is appropriate. A revised Section F is requested. 

Blueberry (47886201.der.wpd): IR-4 submitted six lowbush blueberry (NAFTA growing zones 

1 (n=4) and 5 (n=2)) and six highbush blueberry (NAFTA growing zones 2 (n=3), 5 (n=1), and 

12 (n=2)) field trials conducted during 2006. Each trial consisted of one untreated plot and one 

treated plot with the treated plots receiving a single foliar-directed (highbush blueberry) or foliarbroadcast (lowbush blueberry) application of spirodiclofen (SC; 2 lb ai/gal) at 0.271-0.307 lb 

ai/acre (19-66 GPA; no adjuvant). Single control and duplicate treated blueberry samples were 

harvested 6-8 days after application. Additional samples were collected at one of the highbush 

blueberry and lowbush blueberry field trials at 1, 3, 10, and 14 days after application. 

The harvested samples were analyzed for residues of spirodiclofen per se using an adequately

validated LC/MS/MS method (storage interval has also been validated). Residues of 

spirodiclofen per se in/on highbush blueberry harvested 6-8 days after a single foliar-directed 

application of spirodiclofen (SC) at 0.278-0.288 lb ai/acre were 0.362-1.069 ppm (see Table 4). 

Residues of spirodiclofen per se in/on lowbush blueberry harvested 6-7 days after a single 

broadcast-foliar application of spirodiclofen (SC) at 0.271-0.307 lb ai/acre were 0.100-2.333 

ppm (see Table 4). The highbush blueberry and lowbush blueberry residue decline data indicate 

that residue of spirodiclofen per se declined as the PHI increased from 1 to 14 days. 

Table 4. Summary of Residue Data from Crop Field Trials with Spirodiclofen.

Commodity Total App. Rate

(lb ai/acre)

PHI 

(days)

Residue Levels (ppm)1

n Min. Max. HAFT2 Median Mean Std. Dev.

Highbush blueberry 0.278-0.288 6-8 12 0.362 1.069 1.054 0.551 0.621 0.237

Lowbush blueberry 0.271-0.307 6-7 12 0.100 2.333 2.296 1.282 1.305 0.624

1 Based on the LLMV, the LOQ = 0.01 ppm.

2

 HAFT = highest-average field trial.

860.1520 Processed Food and Feed

Based on Table 1 of OPPTS 860.1000, there are not processed commodities associated with the 

proposed crops. 

860.1850/860.1900 Confined and Field Accumulation in Rotational Crops

Since all of the requested crops are perennials, a discussion concerning the nature/magnitude of 

the residue in rotational crops is unnecessary. 
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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860.1550 Proposed/Recommended Tolerances

Table 5 is a summary of the proposed and recommended tolerance for residues of spirodiclofen

per se. There are no Canadian maximum residue limits (MRLs) in/on the requested crops. 

Codex does have a MRL for residues of spirodiclofen per se in/on black/red currant at 1 ppm; 

since the Codex tolerance is lower than the maximum residues form the submitted field trials, 

harmonization is not possible. 

In accordance with the most recent guidance concerning tolerance expressions, HED 

recommends that the tolerance expression for 180.608(a)(1) and 180.6(a)(2) be changed as 

indicated below. HED notes that this alteration in the tolerance expression does not necessitate a 

change in the currently established or recommended tolerance levels. A revised Section F 

specifying the new tolerance expression, the currently established commodity/tolerance levels,

and the HED-recommended bushberry subgroup 13-07B tolerance should be submitted. 

180.608(a)(1): Tolerances are established for residues of spirodiclofen, including its metabolites and 

degradates, in or on the commodities listed below. Compliance with the following tolerance levels is 

to be determined by measuring only spirodiclofen (3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4.5]dec-3-

en-4-yl 2,2-dimethylbutanoate.

180.608(a)(2): Tolerances are established for residues of spirodiclofen, including its metabolites and 

degradates, in or on the commodities listed below. Compliance with the following tolerance levels is 

to be determined by measuring only spirodiclofen (3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4.5]dec-3-

en-4-yl 2,2-dimethylbutanoate) and its metabolite 3-(2,4-dichlorophenyl)-4-hydroxy-1-oxaspiro[4,5]

dec-3-en-2-one.

Table 5: Tolerance Summary.

Commodity Proposed 

Tolerance (ppm)

HED-Recommended 

Tolerance (ppm) Comments

Bushberry subgroup 13-07B 4.0 3.5 A revised Section F, specifying the correct tolerance 

value and tolerance expression is requested.

Attachment 1: Chemical Structures

Attachment 2: Codex

Attachment 3: Tolerance Calculation

RDI: RAB1 Chemists (16-June-2010)

T. Bloem:S10945:Potomac Yard 1:703-605-0217:7509P:RABI
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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Attachment 1: Chemical Structures

Chemical Name Structure

Spirodiclofen; BAJ2740

3-(2,4-dichlorophenyl)-2-oxo-1-oxaspiro[4,5]dec-3-en-4-yl 

2,2-dimethylbutanoate

O

O

Cl

Cl

O

O H3C

H3C

H3C

BAJ 2510

3-(2,4-dichlorophenyl)-4-hydroxy-1-oxaspiro[4.5]dec-3-en-2-

one O

Cl

Cl

O

HO

3-OH-enol

3-OH-enol spirodiclofen

O

Cl

Cl

O

HO

HO

4-OH-enol

4-OH-enol spirodiclofen

O

Cl

Cl

O

HO

HO
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

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Attachment 2: International residue Limit Status

INTERNATIONAL RESIDUE LIMIT STATUS

Chemical Name: 

3-(2,4-dichlorophenyl)-2-oxo-1-

oxaspiro[4,5]dec-3-en-4-yl 2,2-

dimethylbutanoate

Common Name:

spirodiclofen

X Proposed tolerance

 Reevaluated tolerance

 Other - HED recommended 

tolerances

Date: 4-May-2010

Codex Status (Maximum Residue Limits) U. S. Tolerances

No Codex proposal step 6 or above

No Codex proposal step 6 or above for the crops 

requested

Petition Number: 9E7632

DP Number: 371469

Other Identifier:

Residue definition: spirodiclofen Reviewer/Branch: Tom Bloem/RAB1

Residue definition: spirodiclofen

Crop (s) MRL (mg/kg) Crop(s) Tolerance (ppm)

Currants, black, red, white 1 bushberry subgroup 13-07B 4.0

Limits for Canada Limits for Mexico

 No Limits

√ No Limits for the crops requested

 No Limits (no information after 2004)

 No Limits for the crops requested

Residue definition: 3-(2,4- dichlorophenyl)-2-oxo-1-

oxaspiro[4.5]dec-3-en-4-yl 2,2-dimethylbutanoate.

Residue definition: Mexico adopts Codex and/or 

US MRLs/tolerances for its export purposes.

Crop(s) MRL (mg/kg) Crop(s) MRL (mg/kg)

Notes/Special Instructions: S.Funk, M. Negussie/05/06/2010
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

page 12 of 13

Attachment 3: Tolerance Calculation

Lognormal Probability Plot

0.1 1 2 5 10 20 30 50 70 80 90 95 98 99 99.9

2.0000

1.0000

0.5000

0.2500

y = 0.3534x - 0.5352

R

2 = 0.914

Percentiles

Concentrations

EPA spirodiclofen highbush blueberry 6-8 days 1 x 0.278-0.288 IR-4

Regulator: EPA

Chemical: spirodiclofen

Crop: highbush blueberry

PHI: 6-8 days

App. Rate: 1 x 0.278-0.288

Submitter: IR-4

n: 12

min: 0.36

max: 1.07

median: 0.55

average: 0.62

95th Percentile 99th Percentile 99.9th Percentile

1.1 1.2 1.4

(1.3) (1.6) (--)

1.1 1.4 1.8

(1.6) (2.5) (--)

1.6

1.4

3.5

0.9140

p-value > 0.05 : Do not reject lognormality assumption

Approximate 

Shapiro-Francia

Normality Test 

EU Method I

Normal

UCLMedian95th

95/99 Rule

EU Method II

Distribution-Free

Mean+3SD
Spirodiclofen Summary of Analytical Chemistry and Residue Data D371643

page 13 of 13

Lognormal Probability Plot

0.1 1 2 5 10 20 30 50 70 80 90 95 98 99 99.9

3.0000

1.5000

0.7500

0.3750

0.1875

0.0938

y = 0.7349x + 0.0697

R

2 = 0.7097

Percentiles

Concentrations

EPA spirodiclofen lowbush blueberry 6-7 days 1 x 0.271-0.307 IR-4

Regulator: EPA

Chemical: spirodiclofen

Crop: lowbush blueberry

PHI: 6-7 days

App. Rate: 1 x 0.271-0.307

Submitter: IR-4

n: 12

min: 0.10

max: 2.33

median: 1.28

average: 1.30

95th Percentile 99th Percentile 99.9th Percentile

2.5 3.0 3.5

(3.5) (4.0) (--)

4.5 8.0 14

(11) (25) (--)

3.5

3.5

8.0

0.7097

p-value <= 0.01: Reject lognormality assumption

Approximate 

Shapiro-Francia 

Normality Test 

EU Method I

Normal

UCLMedian95th

95/99 Rule

EU Method II

Distribution-Free

Mean+3SD