Document ID: EPA-HQ-OPP-2014-0110-0013
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2015-03-04T05:00Z

--------------------------------------------------------------------------------

                 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                            WASHINGTON, D.C.  20460
                                       
                                                  OFFICE OF CHEMICAL SAFETY AND
                                                                                               POLLUTION PREVENTION

MEMORANDUM

Date:	10-JUL-2014  

Subject:	Metaldehyde.  Section 3 Registration for New Uses on Vegetable, Legume, Edible Podded [Subgroup 6A], Pea and Bean, Succulent Shelled [Subgroup 6B], Vegetable, Foliage of Legume, Except Soybean [Subgroup 7A], Clover Forage and Hay, and Ginseng; and for Amendments to Existing Tolerances for Tomato [Subgroup 8-10A], and Citrus Fruit [Group 10-10].  Summary of Analytical Chemistry and Residue Data.

PC Code:  053001
DP Barcode:  D418047
Decision No.:  486426
Registration No.:  NA
Petition No.:  3E8223
Regulatory Action: Section 3 Registration
Risk Assessment Type: NA
Case No.: NA
TXR No.:  NA
CAS No.: 108-62-3
MRID Nos.: See MRID table below
40 CFR:  §180.523

FROM:		Austin Doh, Chemist 
		Risk Assessment Branch (RAB) V/VII
		Health Effects Division (HED) (7509P)

THROUGH:	William H. Donovan, Ph.D., Chemist
		Michael S. Metzger, Branch Chief
			RAB V/VII, HED (7509P)
			
	
TO:		Laura Nollen/Barbara Madden, RM 05
			Risk Integration, Minor Use, Emergency Response Branch
			Registration Division (7505P)

Table A.  MRID Summary Table For Metaldehyde
MRID No.
Study Type
Comments
49277201
860.1500 edible podded pea and bean field trials
49277201.der.docx
49277203
860.1500 succulent shelled pea field trials
49277203.der.docx
49277204
860.1500 clover field trials
49277204.der.docx
49277205
860.1500 ginseng field trials
49277205.der.docx
49299501
860.1500 succulent shelled bean field trials
49299501.der.docx
1.0	Executive Summary

The Interregional Research Project Number 4 (IR-4) has submitted a petition for establishing a tolerance for metaldehyde in or on vegetable, legume, edible podded (subgroup 6A), pea and bean, succulent shelled (subgroup 6B), vegetable, foliage of legume, except soybean, (subgroup 7A), clover hay, clover forage, and ginseng; and for replacing the existing tolerances for tomato with tomato subgroup 8-10A, and replacing citrus, fruit group 10 with fruit, citrus, group 10-10.  For clover grown for seed, a regional registration (Pacific NW) was requested while national registrations are intended for the other requested crops.     

Adequate residue chemistry data have been provided to support the new use requests for metaldehyde. The nature of the residue in plants is adequately understood for the purposes of this petition based on previously submitted metabolism studies.  Livestock metabolism and feeding studies have been waived.  Field trials are of adequate number and geographic representation.  Crop field trial data analyses employed validated and sufficiently sensitive analytical methods that determine the residue of concern, and are supported by adequate storage stability data.  
No processed commodities are associated with the new uses proposed in the current petition.  A previously-submitted field rotational crop study indicates that a plant back interval (PBI) of 30 days is appropriate for all rotated crops not listed on the label.  

2.0	Regulatory Recommendations

The residue chemistry database is adequate for the new use requests for metaldehyde, and there are no residue chemistry considerations that would preclude establishment of the recommended tolerances. 

2.1	Data Deficiencies/Data Needs

There are no residue chemistry deficiencies identified for this petition.  

2.2	Tolerance Considerations

2.2.1	Enforcement Analytical Method

EN-CAS(TM) Method No. ENC-3/99, Revision 1 (a gas chromatography/mass spectrometry (GC/MS) method) is acceptable for tolerance enforcement of metaldehyde residues in plants.  For this method, residues in homogenized plant matrices are extracted with dichloromethane (DCM), filtered through sodium sulfate, concentrated with rotary evaporation, then brought back up to volume with DCM before analysis with GC/MS.  The limit of quantitation (LOQ) for metaldehyde in/on plant commodities is 0.05 ppm.

An adequate enforcement method is available to enforce recommended tolerances for the proposed new uses of metaldehyde.

2.2.2	Recommended Tolerances

HED has examined the residue chemistry database for metaldehyde.  Pending submission of revised Sections B (see Section 2.3) and F (see requirements under Proposed Tolerances) there are no residue chemistry issues that would preclude the establishment of tolerances for residues of metaldehyde in/on the requested crops and crop subgroups.  The tolerance expression for metaldehyde [40 CFR §180.523(a)] appropriately reads as follows:

      Tolerances are established for residues of the molluscicide metaldehyde, its metabolites and degradates, in or on the commodities listed in the following table.  Compliance with the specified tolerance levels is to be determined by measuring only metaldehyde, 2,4,6,8-tetramethyl-1,3,5,7-tetroxocane, in or on the commodity.

Table 2.2.2a 	Tolerance Summary for Metaldehyde, §180.523(a).
Commodity
                           Proposed Tolerance (ppm)
                          Recommended Tolerance (ppm)
Comments; Correct Commodity Definition
Vegetable, legume, edible podded, subgroup 6A
                                     0.80
                                     0.80
                                       

Pea and bean, succulent shelled, subgroup 6B
                                     0.20
                                     0.20

Vegetable, foliage of legume, except soybean, subgroup 7A
                                     1.50
                                     1.50
                                       

Tomato subgroup 8-10A
                                     0.24
                                     0.24

Fruit, citrus, group 10-10
                                     0.26
                                     0.26

Ginseng
                                     0.05
                                     0.05

Note to RD:  Upon establishment of the recommended subgroup 8-10A and group 10-10 tolerances, the existing tomato and group 10 tolerance listings should be deleted.

Further, 40 CFR §180.523(c) should read as follows:  

      "Tolerances with a regional registration as defined in 180.1(l) are established for residues of the molluscicide metaldehyde, including its metabolites and degradates, in or on the commodities listed below.  Compliance with the tolerance level specified below is to be determined by measuring only metaldehyde, 2,4,6,8-tetramethyl-1,3,5,7-tetroxocane, in or on the commodity.
      
Table 2.2.2c 	Tolerance Summary for Metaldehyde, §180.523(c).
Commodity
                           Proposed Tolerance (ppm)
                          Recommended Tolerance (ppm)
Comments; Correct Commodity Definition
Clover, forage
                                      0.5
                                     0.60
Pacific Northwest
Clover, hay
                                      0.5
                                     0.60
Pacific Northwest

2.2.3	Revisions to Petitioned-For Tolerances

HED recommends tolerances of 0.60 ppm for clover hay and forage because of the determination that only three independent clover trials were conducted instead of the four trials assumed by the petitioner.  Use of the OECD tolerance calculation procedures with three residue values each for clover hay and forage results in suggested tolerances of 0.60 ppm for both commodities.     

2.2.4	International Harmonization

As there are no CODEX or Canadian MRLs established for metaldehyde, no international harmonization issues are expected to arise from establishment of the recommended tolerances (see Appendix B).

2.3	Label Recommendations

The proposed labels should contain the following restriction:

A 30-day plant back interval (PBI) is appropriate for rotational crops.  Labeled crops may be replanted immediately.  

All other metaldehyde labels should be amended in registration review to contain the aforementioned restriction.

3.0	Introduction

3.1	Chemical Identity

TABLE 3.1.	Nomenclature of Metaldehyde.
Compound
Chemical Structure

Common name
Metaldehyde
Company experimental names
Not applicable
IUPAC name
r-2,c-4,c-6,c-8-tetramethyl-1,3,5,7-tetroxocane  (or)
2,4,6,8-tetramethyl-1,3,5,7-tetraoxacyclo-octane
CAS name
2,4,6,8-tetramethyl-1,3,5,7-tetroxocane
CAS #
108-62-3 (tetramer) and 9002-91-9 (homopolymer)
End-use products/EP
7.5% G (Durham Metaldehyde Granules; EPA Reg No. 5481-103); 
4% P/T (Deadline MPs Mini-Pellets; EPA Reg. No. 5481-511); and 
4% RTU/L (Deadline Force II; EPA Reg. No. 8119-6)

3.2	Physical/Chemical Characteristics

Physiochemical properties for metaldehyde are shown in Table 3.2. 

TABLE 3.2.	Physicochemical Properties of Metaldehyde.
Parameter
Value
Reference
Melting point/range
246°C
Metaldehyde RED, PC Chapter
pH
Not applicable due to the low solubility of metaldehyde in water.
                                       -
Density
1.27 g/cm[3]
                          Metaldehyde RED, PC Chapter
Water solubility (20°C)
0.222 g/L at 20°C

Solvent solubility (g/L at 20.3-22.4°C)
5.21 x 10[-2]  in hexane
0.53            in toluene
1.56            in tetrahydrofuran
1.73            in methanol

Vapor pressure
1 mm Hg at 20°C
6.6 +- 0.3 Pa at 25°C

Dissociation constant (pKa)
3.5 Pa (m[3]/mol) (Henry's Law Constant)

Octanol/water partition coefficient, Log (Kow)
1.33 (log POW = 0.12) at 20°C

3.3	Pesticide Use Pattern/Directions for Use (860.1200)

Table 3.3.  Summary of Directions for Use of Metaldehyde Granular Formulation
                     Application Timing, Type, and  Equip.
                          Formulation [EPA Reg. No.]
                          Application Rate (lb ai/A)
                        Max. No. Application per Season
                   Max. Seasonal Application Rate (lb ai/A)
                                  PHI (days)
                        Use Directions and Limitations
                Vegetable, legume, edible podded (Subgroup 6A)
                  Broadcast (ground & handheld equipment)
                                   71096-13
                                      1.0
                                       3
                                       3
                                   Pre-bloom
                                 RTI = 7 days
                 Pea and Bean, succulent shelled (Subgroup 6B)
                  Broadcast (ground & handheld equipment)
                                   71096-13
                                      1.0
                                       3
                                       3
                                   Pre-bloom
                                 RTI = 7 days
          Vegetable, foliage of legume, except soybean (Subgroup 7A)
                  Broadcast (ground & handheld equipment)
                                   71096-13
                                      1.0
                                       3
                                       3
                                       1
                                 RTI = 7 days
                                Clover, forage*
                  Broadcast (ground & handheld equipment)
                                   71096-13
                                      0.8
                                       2
                                      1.6
                                      30
                                 RTI = 10 days
                                 Clover, hay*
                  Broadcast (ground & handheld equipment)
                                   71096-13
                                      0.8
                                       2
                                      1.6
                                      30
                                 RTI = 10 days
                                    Ginseng
                  Broadcast (ground & handheld equipment)
                                   71096-13
                                      1.0
                                       6
                                       6
                                      21
                                 RTI = 21 days
   * For use in the following states:  Oregon, Idaho, and Washington

The use directions are adequate to allow evaluation of the residue data relative to the proposed uses.  The proposed maximum application rates, RTIs, and PHIs are supported by the submitted field trial data.  Refer to section 2.3 for recommended modifications to the proposed labels.
 
4.0	Metabolite/Degradate Residue Profile

4.1	Nature of the Residue

4.1.1 	Summary of Plant Metabolism (860.1300)

Residue Chemistry Chapter of the RED; DP No. D311889, 05-MAY-2005, F. Fort

The qualitative nature of metaldehyde residues in plants is understood based on the adequate lettuce and sugar beet metabolism studies (DP Barcode D224844, S. Hummel, 7/02/96).  The HED Metabolism Committee concluded that the regulated residue of concern in plants is parent metaldehyde, per se.

In the lettuce metabolism study, radioactive residues were taken up and translocated to leaves following a single directed application of [[14]C]metaldehyde to the soil at a rate equivalent to 13.8 lb ai/A (10x).  The maximum total radioactive residues (TRR) were 4.43 ppm and 3.78 ppm in the inner and outer lettuce leaves, respectively, with a PHI of 28 days.  Up to 95.3% of TRR was identified as the parent metaldehyde.

In the sugar beet metabolism study, a single directed application of [[14]C]metaldehyde was made to the soil at a rate equivalent to 13.8 lb ai/A (10x).  The TRR were 1.65-5.60 ppm in/on sugar beet foliage and 0.30-1.13 ppm in/on sugar beet root (PHI = 48days), indicating uptake and translocation to foliage.  Metaldehyde was the only radioactive residue identified in the organic fractions of foliage (~33% TRR, 1.84 ppm) and root (~35% TRR, 0.39 ppm).  Although no analytical analyses of the nonextractable residues of foliage (43.2% TRR, 2.42 ppm) and root (43.4% TRR, 0.49 ppm) were conducted, overall the plant metabolism data for metaldehyde support the HED Metabolism Committee's decision to regulate only the parent in the tolerance expression for plant commodities.

4.1.2	Summary of Livestock Metabolism (860.1300)

Residue Chemistry Chapter of the RED; DP No. D311889, 05-MAY-2005, F. Fort

Based upon the rapid degradation of metaldehyde to acetaldehyde in mammalian systems and the subsequent incorporation of acetaldehyde into the tricarboxylic acid cycle, the Agency has concluded that the transfer of metaldehyde residues in livestock commodities is unlikely.  Therefore, the requirements for livestock metabolism and feeding studies have been waived (Greybeard Committee: Metaldehyde, 3/11/97).  

4.1.3	Summary of Confined Rotational Crops (860.1850)

D298113, T. Jimerson, 15-FEB-2005

On December 9, 2004, the Chemistry Science Advisory Council (ChemSAC) granted a waiver for OPPTS Guideline 860.1850, Confined Accumulation in Rotational Crops for the chemical metaldehyde, provided that a field accumulation in rotational crop study is conducted.  The rationale was that because of its chemical structure (a tetramer of acetaldehyde), the primary metabolite would be acetaldehyde, a chemical whose metabolism in plants and animals is well documented.  Also, because it is likely that total radioactive residues (TRR) greater than 0.01 ppm would be found in a confined rotational crop study, a field accumulation in rotational crop study was requested, submitted, and reviewed (see Section 5.3.2).  

4.2	Residues of Concern Summary and Rationale

The qualitative nature of metaldehyde residues in plants is understood based on lettuce and sugar beet metabolism studies.  The HED Metabolism Committee (7/2/96) concluded that the regulated residue of concern in plants is parent metaldehyde.  This conclusion was confirmed in the Metaldehyde Reregistration Eligibility Decision (RED) document (D327385, M. Lloyd et. al., April 3, 2006).  Table 4.2 summarizes the metaldehyde residues of concern for the tolerance expression and for risk assessment in the matrices indicated.

Table 4.2.   Summary of Metabolites and Degradates to be included in the Risk Assessment and Tolerance Expression
Matrix
Residues included in Risk Assessment
Residues included in Tolerance Expression
Plants
Primary Crop
Metaldehyde
Metaldehyde

Rotational Crop
Metaldehyde
Metaldehyde
Livestock
Not Applicable
Not Applicable
Drinking Water
Metaldehyde
Not Applicable

5.0	Residue Profile

5.1	Residue Analytical Methods (860.1340) 

5.1.1	Data Collection Methods

IR-4 made use of the existing metaldehyde enforcement method for data collection purposes.  The method, entitled "Analytical Residue Method for the Determination of Metaldehyde in Crops by GC/MS" (EN-CAS(TM) Method No. ENC-3/99, Revision 1), has been used for the determination of metaldehyde in a wide variety of crop matrices.  The method description, method validation data, and an independent laboratory (ILV) validation of the method were reviewed in support of the metaldehyde RED.

For this method, residues in homogenized plant matrices are extracted with dichloromethane (DCM), filtered through sodium sulfate, concentrated with a TurboVap evaporation apparatus, then brought back up to volume with DCM before analysis.  Samples were analyzed by GC/MS using the m/z 89 and 45 ions for quantitation and confirmation, respectively.  Clover hay samples were allowed to soak in water prior to extraction. The limit of quantitation (LOQ) for metaldehyde in/on plant commodities is 0.05 ppm.

Method validation data for the GC/MS method demonstrated adequate method recoveries from plant commodities (bean, pea, clover, and ginseng) fortified with metaldehyde at 0.05-5.0 ppm.  Recoveries were within the acceptable 70-120% range and had standard deviations of < 20%.  

5.1.2	Multi-Residue Methods (860.1360)

D315914, J. Deluzio, 13-APR-2005

There are no analytical methods listed in PAM, Vol. II for the analysis of metaldehyde.   The FDA multiresidue methods are not suitable for analysis of metaldehyde.  The GC/FID response for metaldehyde in Level I testing (Module DG6, 130C) gave an inadequate response as the relative retention time for metaldehyde was <0.3, and Level II testing could not be performed.  In addition, solvent front and matrix interferences precluded quantitation of metaldehyde through Protocol D.  

5.1.3	Tolerance Enforcement Methods

EN-CAS(TM) Method No. ENC-3/99, Revision 1 is acceptable for tolerance enforcement of metaldehyde residues in plants.  For this method, residues in homogenized plant matrices (except clover hay) are extracted with dichloromethane (DCM) containing sodium sulfate, filtered, concentrated, and analyzed by GC/MS. Clover hay samples were allowed to soak in water prior to extraction.  The limit of quantitation (LOQ) for metaldehyde in/on plant commodities is 0.05 ppm. Since this method was used for data collection and adequate validation data were reported, an adequate enforcement method is available to enforce tolerances for the proposed new uses of metaldehyde.
5.1.4	Submittal of Analytical Reference Standards (860.1650)

The analytical standard for metaldehyde (CAS # 108-62-3) at the EPA National Pesticide Standards Repository will expire on January 31[st], 2016 [personal communication from T. Cole of ACB/BEAD to W. Donovan, 07/10/2014].  A fresh reference standard should be provided to the Repository, and then replenished as requested by the Repository.  The reference standard should be sent to the Analytical Chemistry Lab, which is located at Fort Meade, to the attention of Theresa Cole at the following address:

	USEPA
	National Pesticide Standards Repository/Analytical Chemistry Branch/OPP
	701 Mapes Road
	Fort George G. Meade, MD  20755-5350

The full 9 digit zip code is mandatory or the mail will be returned.

5.2	Storage Stability (860.1380)

As detailed in the residue chemistry chapter of the metaldehyde RED, acceptable storage stability studies for metaldehyde have been reported.  Thus, metaldehyde is stable in frozen storage for at least 8 months in citrus oil, 12 months in lettuce, strawberry, broccoli, and oranges, and 23 months in tomatoes.  Furthermore, additional storage stability data were submitted in support of crop field trial data in 2013 (D418047, W. Donovan).  In these studies metaldehyde was found to be stable for 10.6 months in celery, 18.3 months in corn forage, 6.3 months in corn grain, 9.6 months in corn stover, 15.9 months in grass (forage, hay), 10.5 months in mint leaf, 24.2 months in mint oil, 7.8 months in soybean seed, 12.4 months in taro leaf and corm, 14.8 months in radish (roots, tops), sorghum (forage, grain, stover) and wheat (forage, hay, grain and straw).

In support of the crop field trial data submitted for the proposed new uses of metaldehyde, concurrent storage stability studies were conducted for bean, pea, clover and ginseng.  These studies confirm and extend the previous findings of residue stability, with recoveries in the acceptable range of 70-120% for the intervals needed to cover the sample storage intervals from the field trial studies, see Table 5.2.2.  

TABLE 5.2.2.	Summary of Storage Conditions in Primary Crop, Processing Studies, and Rotational Crops.

Crop

Matrix
                           Storage Temperature (°C)
                        Maximum Storage Duration (days)
               Interval of Demonstrated Storage Stability (days)
                                Primary Crops 
Bean
Edible Pod

                                     <= 0

346
366

Shelled Succ.

459
442

Foliage

355
366
Pea
Edible Pod

351
368

Shelled Succ.

277
279

Foliage

371
368
Clover
Hay

666
670

Forage

530
552
Ginseng
Root

412
430

Thus, metaldehyde is stable in frozen storage for at least 7.7 months in bean (pod and foliage), 10.0 months in pea (pod and foliage), 12.9 months in bean (succulent shelled), 2.9 months in pea (succulent shelled), 13.6 months in clover forage, 18.3 months in clover hay, and 14.1 months in ginseng.     

5.3	Residue Data

5.3.1	Crop Field Trials (860.1500)
49277201.der (Bean and pea, edible podded)
49277203.der (Pea, succulent shelled)
49277204.der (Clover)
49277205.der (Ginseng)
49299501.der (Bean, succulent shelled)

The crop field trial data submitted in support of this petition were generated by IR-4.  

Bean and Pea (Edible Podded) Field Trials [Subgroups 6A and 7A]

Seven bean trials were conducted in the North American Free Trade Agreement (NAFTA) Growing Zone 1 (NY; 1 trial), 2 (NC; 1 trial), 3 (FL; 1 trial), 5 (OH and WI; 2 trials), 10 (CA; 1 trial), and 11 (WA; 1 trial); and three pea trials were conducted in Zones 2 (GA; 1 trial), 10 (CA; 1 trial), and 11 (ID; 1 trial).  

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received three soil broadcast applications of a 4% mini-pelleted (P/T) formulation of metaldehyde (Deadline[(R)] M-Ps[TM]) at 0.99-1.00 lb ai/A/application, with a 6- to 8-day retreatment interval (RTI), for a total seasonal rate of 2.99-3.01 lb ai/A.  Applications were made during cotyledon through vegetative stages of development using soil broadcast applications.  No adjuvants were used with these types of applications.  Bean and pea were harvested at pre harvest intervals (PHIs) of 30-97 days to evaluate edible podded bean, 1-22 days to evaluate bean foliage, 39-55 days to evaluate edible podded peas and 1-35 days to evaluate pea foliage.  Residue decline was not evaluated.

Residues of metaldehyde were found in all but one of the pea trials, and all but three of the bean (podded) trials. A summary of the field trial results is shown in Table 5.3.1.1, below.

TABLE 5.3.1.1	Summary of Residue Data from Crop Field Trials with Metaldehyde.  
Commodity
                             Total Rate (lb ai/A)
                                  PHI (days)
                               Residue Levels[1]
                                     (ppm)

                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                   Std. Dev.
Bean, edible podded
                                  2.988-3.012
                                     30-97
                                       7
                                   <0.05
                                     0.432
                                   <0.05
                                     0.347
                                    0.0508
                                     0.159
                                     0.140
Bean, foliage
                                       
                                     1-22
                                       7
                                    0.0600
                                     0.668
                                    0.0827
                                     0.647
                                     0.172
                                     0.269
                                     0.222
Pea, edible podded
                                  2.997-3.000
                                     39-55
                                       3
                                   <0.05
                                     0.258
                                   <0.05
                                     0.252
                                    0.0970
                                     0.133
                                     0.105
Pea, foliage
                                       
                                     1-35
                                       3
                                   <0.05
                                     0.352
                                   <0.05
                                     0.330
                                     0.208
                                     0.196
                                     0.140
[1]  Except for sample min/max, values reflect per trial averages; n = no. of field trials.  For calculation of median, mean, and standard deviation, the LOQ of 0.05 ppm was used for any results reported as <LOQ.
[2]  LAFT = lowest average field trial; HAFT = highest average field trial.

The number of bean field trials and their geographical distribution are adequate.  The samples were analyzed using a suitable method and the sample storage intervals are supported by storage stability data.  The edible podded and foliage data sets were analyzed using the OECD tolerance calculation procedures to determine a recommended tolerance level of 0.8 ppm for edible podded bean, 0.6 ppm for edible podded pea; 1.5 ppm for bean foliage, and 0.8 ppm for pea foliage. The higher value for the subgroup was selected for tolerance determination, giving a recommended tolerance of 0.8 ppm for edible podded (subgroup 6A) and 1.5 ppm for foliage matrices (subgroup 7A) (see Appendix C). 

Bean (Succulent Shelled) Field Trials [Subgroup 6B]

A total of 6 field trials were conducted in the United States during the 2011 growing season in the NAFTA Growing Zone 2 (MD and NC; 3 trials), 5 (MI; 1 trial), 10 (CA; 1 trial) and 11 (ID; 1 trial).  The two Clinton, NC trials were considered independent due to the use of different lima bean varieties (Thorogreen [NC13] and Fordhook 242 [NC14]) and a difference in application timing of approximately 3 weeks.

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received three soil broadcast applications of a 4% mini-pelleted (P/T) formulation of metaldehyde (Deadline[(R)] M-Ps[TM]) at 1.00 lb ai/A/application, with a 6- to 8-day RTI, for a seasonal rate of 3.00 lb ai/A.  Applications were made during cotyledon through vegetative stages of development using ground equipment.  No adjuvants were used with these types of applications.  Beans (succulent shelled) were harvested at PHIs of 48-83 days.  Residue decline was not evaluated.

Residues of metaldehyde were found in 2 bean (succulent shelled) trials.  A summary of the field trial results is shown in Table 5.3.1.2, below.

TABLE 5.3.1.2.	Summary of Residue Data from Crop Field Trials with Metaldehyde.  
Commodity
                             Total Rate (lb ai/A)
                                  PHI (days)
                               Residue Levels[1]
                                     (ppm)

                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                   Std. Dev.
Beans (succulent shelled)
                                   2.99-3.00
                                     48-83
                                       6
                                   <0.05
                                     0.152
                                   <0.05
                                     0.139
                                     0.050
                                     0.068
                                     0.035
[1]  Except for sample min/max, values reflect per trial averages; n = no. of field trials.  For calculation of median, mean, and standard deviation, the LOQ of 0.05 ppm was used for any results reported as <LOQ.
[2]  LAFT = lowest average field trial; HAFT = highest average field trial.

The number of bean field trials and their geographical distribution are adequate.  The samples were analyzed using a suitable method and the sample storage intervals are supported by storage stability data.  The succulent shelled bean data were analyzed using the OECD tolerance calculation procedures to determine the recommended tolerance level of 0.20 ppm (see Appendix C). 

Pea (Succulent Shelled) Field Trials [Subgroup 6B]

A total of 7 field trials on pea were conducted in the United States during the 2010 growing season in NAFTA Growing Zones 1 (NY; 1 trial), 5 (MI, OH, and WI; 3 trials), 10 (CA; 1 trial), 11 (ID; 1 trial) and 12 (OR; 1 trial).

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received three soil broadcast applications of a 4% mini-pelleted (P/T) formulation of metaldehyde (Deadline[(R)] M-Ps[TM]) at 1.00-1.08 ai/A/application, with a 6- to 8-day retreatment interval (RTI), for a total seasonal rate of 3.00-3.25 lb ai/A.  Applications were made during newly emerged through vegetative stages of development using ground equipment.  No adjuvants were used with these types of application.  Pea (succulent shelled) was harvested at preharvest intervals (PHIs) of 21-125 days.  Residue decline was not evaluated.

Residues of metaldehyde were found in 4 pea trials.  A summary of the field trial results is shown in Table 5.3.1.3, below.

TABLE 5.3.1.3.	Summary of Residue Data from Crop Field Trials with Metaldehyde.  
Commodity
                            Total Rate lb a.i./A 
                                  PHI (days)
                               Residue Levels[1]
                                     (ppm)

                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                   Std. Dev.
Pea (succulent shelled)
                                  2.997-3.246
                                    21-125
                                       7
                                   <0.05
                                     0.140
                                   <0.05
                                     0.130
                                     0.083
                                     0.080
                                     0.031
[1]  Except for sample min/max, values reflect per trial averages; n = no. of field trials.  For calculation of median, mean, and standard deviation, the LOQ of 0.05 ppm was used for any results reported as <LOQ.
[2]  LAFT = lowest average field trial; HAFT = highest average field trial.

The number of pea field trials and their geographical distribution are adequate.  The samples were analyzed using a suitable method and the sample storage intervals are supported by storage stability data.  The succulent shelled pea data were analyzed using the OECD tolerance calculation procedures to determine the recommended tolerance level of 0.20 ppm. 

As both studies conducted on succulent shelled legumes (bean and pea) resulted in suggested tolerances of 0.2 ppm, the recommended tolerance for subgroup 6B is 0.20 ppm (see Appendix C). 

Clover Field Trials

A total of 3 field trials on clover were conducted in the United States during the 2009 growing season in NAFTA Growing Zones 11 (WA, 1 trial) and 12 (OR, 2 trials).  The submitted study report indicated that three trials were conducted in OR (OR14, OR15, and OR16).  However, consideration of the trial conditions showed that trials designated OR15 and OR16 are not independent; instead they are replicate treatments at one trial site.  The soil types and clover varieties were identical in OR15 and OR16 and the only difference noted was a one week separation in application dates.  Trial OR14 was considered independent from OR15 and OR16 due to the different soil characteristics as compared to those in the other plots.  

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received two broadcast soil applications of a 4% mini-pelleted (P/T) bait of metaldehyde (Deadline[(R)] M-Ps[TM]) at 0.80-0.84 lb ai/A/application, with a 10- to 12-day RTI, for a total seasonal rate of 1.60-1.66 lb ai/A.  Applications were made during vegetative to blooming stages of development.  No adjuvants were used with these types of application.  Clover forage was harvested at PHIs of 23-29 days.  Clover hay was harvested at PHIs of 29-51 days and was allowed to dry for 5-8 days prior to collection.  Residue decline was not evaluated.

Residues of metaldehyde were found in all 3 clover trials.  A summary of the field trial results is shown in Table 5.3.1.4, below.

TABLE 5.3.1.4.	Summary of Residue Data from Crop Field Trials with Metaldehyde.  
Commodity
                            Total Rate lb a.i./A 
                                  PHI (days)
                               Residue Levels[1]
                                     (ppm)

                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                   Std. Dev.
Clover (hay)
                                  1.598-1.661
                                     23-29
                                       3
                                   <0.05
                                     0.275
                                     0.053
                                     0.235
                                     0.165
                                     0.151
                                     0.110
Clover (forage)
                                  1.598-1.661
                                     29-51
                                       3
                                   <0.05
                                     0.255
                                   <0.05
                                     0.241
                                     0.050
                                     0.114
                                     0.092
[1]  Except for sample min/max, values reflect per trial averages; n = no. of field trials.  For calculation of median, mean, and standard deviation, the LOQ of 0.05 ppm was used for any results reported as <LOQ.
[2]  LAFT = lowest average field trial; HAFT = highest average field trial.

The number of clover field trials and their geographical distribution are adequate for the requested regional registration limited to the Pacific Northwest.  The samples were analyzed using a suitable method and the sample storage intervals are supported by storage stability data.  The clover forage and hay data were analyzed separately using the OECD tolerance calculation procedures.  For both matrices, the recommended tolerance was determined to be 0.60 ppm (see Appendix C). 

Ginseng Field Trials

A total of 4 crop field trials on ginseng were conducted in the United States during the 2011 growing season in NAFTA Growing Zone 5 (WI; 4 trials).  Because the field trial sites were separated by ~16-27 miles and had different soil types (loam, silt loam, loamy sand, and sandy loam), they are considered independent trials.   

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received six foliar broadcast applications of a 4% mini-pelleted (P/T) formulation of metaldehyde (Deadline[(R)] M-Ps[TM]) at 1.0 lb ai/A/application, with a 20- to 22-day RTI, for a total seasonal rate of 6.0 lb ai/A.  Applications were made during vegetative through fruiting stages of development using ground equipment.  No adjuvants were used with these types of application.  Ginseng was harvested at PHIs of 21-22 days and was allowed to dry (drying period not reported).  Samples were collected at PHIs of 7, 14, 21, and 28 days from one trial to assess residue decline.  No detectable residue levels were found in any ginseng sample; thus, no residue decline pattern was discernible. 

Residues of metaldehyde were not found in any of the trials above the LOQ of 0.05 ppm.  A summary of the field trial results is shown in Table 5.3.1.5, below.

TABLE 5.3.1.5.	Summary of Residue Data from Crop Field Trials with Metaldehyde.  
Commodity
                            Total Rate lb a.i./A 
                                  PHI (days)
                               Residue Levels[1]
                                     (ppm)

                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                   Std. Dev.
Ginseng (root)
                                       
                                      6.0
                                       
                                     21-22
                                       4
                                   <0.05
                                   <0.05
                                   <0.05
                                   <0.05
                                     0.05
                                     0.05
                                      N/A
[1]  Except for sample min/max, values reflect per trial averages; n = no. of field trials.  For calculation of median, mean, and standard deviation, the LOQ of 0.05 ppm was used for any results reported as <LOQ.
[2]  LAFT = lowest average field trial; HAFT = highest average field trial.

The number of ginseng field trials and their geographical distribution are adequate.  The samples were analyzed using a suitable method and the sample storage intervals are supported by storage stability data.  No detectable residue levels were found in any ginseng sample; thus, the recommended tolerance level of 0.05 ppm was based on the analytical method LOQ.

Tomato [Subgroup 8-10A] and Citrus [Group 10-10] proposal

Tolerances are established for metaldehyde on tomato at 0.24 ppm and on Fruit, citrus, group 10 at 0.26 ppm. On December 8, 2010, the Federal Register published a final rule with revisions to the fruiting vegetables crop group and the citrus fruit crop group.  HED concludes that it is appropriate to translate the established tolerance levels for tomato and citrus, fruit, group 10 to tomato subgroup 8-10A and citrus, fruit, group 10-10, respectively; and then to remove the tolerance listings for tomato and group 10.

5.3.2	Field Rotational Crops (860.1900) 
D408745, W. Donovan, 12-JUL-2013
47623004.der

Lonza, Inc. submitted a limited field rotational crop study with metaldehyde on radish, germ sorghum, and winter wheat.  Two field trials were conducted in the Unites States, encompassing Regions 5 (1 trial in Michigan) and Region 10 (1 trial in California) during the 2005-2006 growing season.  At each test site, three applications of metaldehyde were made to bare ground at a nominal target application rate of 1.0 lb ai/A/application and a 14-day RTI, for a total of 3.0 lb ai/A/season.  Radish plants were planted at nominal plant back intervals (PBI) of 30, 120 and 365 days.  Sorghum plants were planted at nominal PBIs of 30 and 365 days, while wheat plants were planted at a nominal 120-day PBI.  Plants were harvested at maturity and analyzed using the analytical method EN-CAS(TM) No. ENC-3/99, Revision 1.  The following plant matrices were analyzed for residues of metaldehyde:  radish  -  tops and roots; sorghum  -  forage, grain, and stover; and wheat  -  forage, grain, hay, and straw.  Leafy vegetables were not included in the study because of the availability of magnitude of the residue field trial data in/on broccoli, cabbage, mustard greens, and leaf lettuce reflecting primary crop uses.

Conclusions:  The maximum frozen storage interval for any sample was 14 months.  Concurrent storage stability data demonstrated stability in all matrices tested for at least 15 months.  Residues of metaldehyde were not detected above the LOQ (0.05 ppm) in any of the samples analyzed at any PBI.  Based on use of the appropriate application rate, adequate crop diversity in the tested crops, and the results showing that metaldehyde residues are not taken up by rotational crops, HED concludes that 30-day PBIs are appropriate for rotational crops.  This rotational crop PBI specification should be included on all metaldehyde labels concerning agricultural crop uses.  Labeled crops may be replanted immediately.  

5.3.3	Processed Food and Feed (860.1520)  

5.3.4	Meat, Milk, Poultry and Eggs (860.1480)

Not applicable as the Agency approved a waiver for livestock feeding studies (Greybeard Committee: Metaldehyde, 3/11/97).

5.4	Food Residue Profile

Adequate residue chemistry data have been provided for metaldehyde.  Field trials are of adequate number and geographic representation.  Data analyses employed validated analytical methods and are supported by appropriate storage stability data. The Agency waived livestock metabolism and feeding studies; thus, all uses of metaldehyde are classified under 40 CFR §180.6 (a) (3), no reasonable expectation of finite residues with respect to residues in livestock commodities.  No processed commodities are associated with the new uses proposed in the current petition.  Limited rotational crop field trial  studies have demonstrated that residues are not expected in crops planted 30-days after metaldehyde is applied to soil; therefore, 30-day plant back intervals (PBIs) are appropriate for crops in rotation to primary crops.  

6.0	Tolerance Derivation

The recommended tolerances for metaldehyde were derived by 1) use of the OECD MRL calculation procedures for crops with measurable residue levels, 2) use of the LOQ for crops where residues in the field trials were not measurable (ginseng), and 3) direct translation where appropriate (subgroup 8-10A and group 10-10). 

List of Appendices
   A. Number of Crop Field Trials and Geographical Distributions.
   B. International Residue Limits Table.
   C. Tolerance Calculations.

Appendix A

TABLE A.1.1.	Trial Numbers and Geographical Locations.

NAFTA Growing Zones
                                     Bean
                                      Pea

                                   Submitted
                                 Requested[1]
                                   Submitted
                                 Requested[2]

                                       
                                    Canada
                                     U.S.
                                       
                                    Canada
                                     U.S.
1
                                       1
                                      --
                                      1/1
                                      --
                                      --
                                      --
1A
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
2
                                       1
                                      --
                                      1/1
                                       1
                                      --
                                      --
3
                                       1
                                      --
                                      1/1
                                      --
                                      --
                                      --
4
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
5
                                       2
                                      --
                                      3/2
                                      --
                                      --
                                      --
5A
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
5B
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
6
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
7
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
7A
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
8
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
9
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
10
                                       1
                                      --
                                      1/0
                                       1
                                      --
                                      --
11
                                       1
                                      --
                                      1/1
                                       1
                                      --
                                      --
12
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
13
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
14
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
15
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
16
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
17
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
18
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
19
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
20
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
21
                                      --
                                      --
                                      --
                                      --
                                      --
                                      --
Total
                                       7
                                      --
                                      8/6
                                       3
                                      --
                                       3
[1]  As per OCSPP 860.1500, Tables 1, 3, and 5.  The second number reflects a 25% reduction in the number of trials allowed for the crop as a representative commodity in support of a crop group/subgroup tolerance or when application results in no quantifiable residues.
[2]  Geographic representation is not specified for crops requiring <=3 trials.

TABLE A.1.2.	Trial Numbers and Geographical Locations.
NAFTA Growing Regions
                           Bean (succulent shelled)

                                   Submitted
                                 Requested[1]

                                       
                                    Canada
                                     U.S.
1
                                      --
                                      --
                                      --
1A
                                      --
                                       
                                      --
2
                                       3
                                      --
                                      4/3
3
                                      --
                                      --
                                      --
4
                                      --
                                      --
                                      --
5
                                       1
                                      --
                                      1/1
5A
                                      --
                                      --
                                      --
5B
                                      --
                                      --
                                      --
6
                                      --
                                      --
                                      --
7
                                      --
                                      --
                                      --
7A
                                      --
                                      --
                                      --
8
                                      --
                                      --
                                      --
9
                                      --
                                      --
                                      --
10
                                       1
                                      --
                                      2/1
11
                                       1
                                      --
                                      1/1
12
                                      --
                                      --
                                      --
13
                                      --
                                      --
                                      --
14
                                      --
                                      --
                                      --
15
                                      --
                                      --
                                      --
16
                                      --
                                      --
                                      --
17
                                      --
                                      --
                                      --
18
                                      --
                                      --
                                      --
19
                                      --
                                      --
                                      --
20
                                      --
                                      --
                                      --
21
                                      --
                                      --
                                      --
Total
                                       6
                                       
                                      8/6
[1] As per Table 5 of 860.1500 for bean, lima, green; the second number reflects a 25% reduction in the number of field trials allowed for the crop as a representative commodity in support of a crop group/subgroup tolerance or when application results in no quantifiable residues.  

TABLE A.1.3.	Trial Numbers and Geographical Locations.
NAFTA Growing Regions
                            Pea (Succulent Shelled)

                                   Submitted
                                 Requested[1]

                                       
                                    Canada
                                     U.S.
1
                                       1
                                      --
                                    1/1[2]
1A
                                      --
                                       
                                      --
2
                                      --
                                      --
                                    1/1[2]
3
                                      --
                                      --
                                      --
4
                                      --
                                      --
                                      --
5
	3
                                      --
                                      4/3
5A
                                      --
                                      --
                                      --
5B
                                      --
                                      --
                                      --
6
                                      --
                                      --
                                      --
7
                                      --
                                      --
                                      --
7A
                                      --
                                      --
                                      --
8
                                      --
                                      --
                                      --
9
                                      --
                                      --
                                      --
10
                                       1
                                      --
                                      --
11
                                       1
                                      --
                                      2/1
12
                                       1
                                      --
                                      1/1
13
                                      --
                                      --
                                      --
14
                                      --
                                      --
                                      --
15
                                      --
                                      --
                                      --
16
                                      --
                                      --
                                      --
17
                                      --
                                      --
                                      --
18
                                      --
                                      --
                                      --
19
                                      --
                                      --
                                      --
20
                                      --
                                      --
                                      --
21
                                      --
                                      --
                                      --
Total
                                       7
                                       
                                      8/6
[1] As per Table 5 of 860.1500 for pea, garden, succulent; the second number reflects a 25% reduction in the number of field trials allowed for the crop as a representative commodity in support of a crop group/subgroup tolerance or when application results in no quantifiable residues.
2  Either region is acceptable.

TABLE A.1.4.	Trial Numbers and Geographical Locations.
NAFTA Growing Regions
                                     Clover

                                   Submitted
                                   Requested

                                       
                                    Canada
                                     U.S.
1
                                      --
                                      --
                                      1/1
1A
                                      --
                                       
                                      --
2
                                      --
                                      --
                                      1/1
3
                                      --
                                      --
                                      --
4
                                      --
                                      --
                                      1/1
5
	--
                                      --
                                      3/2
5A
                                      --
                                      --
                                      --
5B
                                      --
                                      --
                                      --
6
                                      --
                                      --
                                      1/1
7
                                      --
                                      --
                                      1/1
7A
                                      --
                                      --
                                      --
8
                                      --
                                      --
                                      1/1
9
                                      --
                                      --
                                      1/0
10
                                      --
                                      --
                                    1/1[1]
11
                                       1
                                      --
                                    1/1[1]
12
                                     2[2]
                                      --
                                      --
13
                                      --
                                      --
                                      --
14
                                      --
                                      --
                                      --
15
                                      --
                                      --
                                      --
16
                                      --
                                      --
                                      --
17
                                      --
                                      --
                                      --
18
                                      --
                                      --
                                      --
19
                                      --
                                      --
                                      --
20
                                      --
                                      --
                                      --
21
                                      --
                                      --
                                      --
Total
                                     3[3]
                                       
                                     12/9
1  Either region is acceptable.
2  HED has concluded that two trials (OR 15 and OR 16) conducted in Aurora, OR (Zone 12) should constitute a single trial with replicate samples for the purpose of 860.1500 data requirements, while trial OR14 is independent.
[3] This study is to support a regional registration in the Pacific Northwest on clover grown for seed.

TABLE A.1.5.	Trial Numbers and Geographical Locations.
NAFTA Growing Regions
                                    Ginseng

                                   Submitted
                                 Requested[1]

                                       
                                    Canada
                                     U.S.
1
                                      --
                                      --
                                      --
1A
                                      --
                                       
                                      --
2
                                      --
                                      --
                                      --
3
                                      --
                                      --
                                      --
4
                                      --
                                      --
                                      --
5
	4
                                      --
                                      --
5A
                                      --
                                      --
                                      --
5B
                                      --
                                      --
                                      --
6
                                      --
                                      --
                                      --
7
                                      --
                                      --
                                      --
7A
                                      --
                                      --
                                      --
8
                                      --
                                      --
                                      --
9
                                      --
                                      --
                                      --
10
                                      --
                                      --
                                      --
11
                                      --
                                      --
                                      --
12
                                      --
                                      --
                                      --
13
                                      --
                                      --
                                      --
14
                                      --
                                      --
                                      --
15
                                      --
                                      --
                                      --
16
                                      --
                                      --
                                      --
17
                                      --
                                      --
                                      --
18
                                      --
                                      --
                                      --
19
                                      --
                                      --
                                      --
20
                                      --
                                      --
                                      --
21
                                      --
                                      --
                                      --
Total
                                       4
                                       
                                    3 or 2
[1] As per OPPTS 860.1500, Table 1 for ginseng; trial locations are not specified for crops requiring <=3 field trials.  According to "Food and Feed Crops of the United States" (G.M. Markle, J.J. Baron, and B.A. Schneider.  Second Edition, Meister Publishing Co. 1998), ginseng is grown in Zones 1, 2, 4, and 5 with Zone 5 being the major cultivated region.

Appendix B.  International Residue Limits Table

Appendix B.  International Residue Limits Table

Table B1.  Summary of US and International Tolerances and Maximum Residue Limits for Metaldehyde (053001)
Residue Definition:
US
Canada
Mexico[2]
Codex
40 CFR 180.523:
Plant: Metaldehyde
None

None
Commodity[1]
Recommended Tolerance (ppm) /Maximum Residue Limit (mg/kg)

US
Canada
Mexico[2]
Codex
Vegetable, legume, edible podded, subgroup 6A
                                     0.80
                                       

Pea and bean, succulent shelled, subgroup 6B
                                     0.20
                                       

Vegetable, foliage of legume, except soybean, subgroup 7A
                                     1.50
                                       

Tomato subgroup 8-10A
                                     0.24
                                       

Fruit, citrus, group 10-10
                                     0.26
                                       

Clover, forage
                                     0.60
                                       

Clover, hay
                                     0.60
                                       

Ginseng
                                     0.05
                                       

Completed:  M. Negussie; 06/18/14
[1] Includes only commodities of interest for this action.  Tolerance values should be the HED recommendations and not those proposed by the applicant.
2 Mexico adopts US tolerances and/or Codex MRLs for its export purposes.

Appendix C. Results of OECD Tolerance Calculations

                                  Metaldehyde
                           Bean (Succulent Shelled)
                                      USA
                               1 lb ai/A, 3 aps
 
 
Total number of data (n)
                                       6
Percentage of censored data
                                      67%
Number of non-censored data
                                       2
Lowest residue
                                     0.050
Highest residue
                                     0.139
Median residue
                                     0.050
Mean
                                     0.068
Standard deviation (SD)
                                     0.035
Correction factor for censoring (CF)
                                     0.556

 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.139
- Mean + 4 SD
                                     0.210
- CF x 3 Mean
                                     0.113
Unrounded MRL
                                     0.210
 
                                       
Rounded MRL
                                      0.2
 
                                       
 High uncertainty of MRL estimate.
[High level of censoring]

                               Residues (mg/kg)
                                       n
                                     0.139
                                       1
                                     0.069
                                       1
                                     0.050
                                       4

                                  Metaldehyde
                             Bean (Pods with Seed)
                                      USA
                              1.0 lb ai/A, 3 aps
 
 
Total number of data (n)
                                       7
Percentage of censored data
                                      43%
Number of non-censored data
                                       4
Lowest residue
                                     0.050
Highest residue
                                     0.347
Median residue
                                     0.051
Mean
                                     0.159
Standard deviation (SD)
                                     0.140
Correction factor for censoring (CF)
                                     0.714
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.347
- Mean + 4 SD
                                     0.718
- CF x 3 Mean
                                     0.340
Unrounded MRL
                                     0.718
 
                                       
Rounded MRL
                                      0.8
 
                                       
 
 High uncertainty of MRL estimate.
[Small dataset]

                               Residues (mg/kg)
                                       n
                                     0.05
                                       3
                                     0.347
                                       1
                                     0.33
                                       1
                                    0.2325
                                       1
                                    0.05075
                                       1

                                  Metaldehyde
                                Bean (Foliage)
                                      USA
                              1.0 lb ai/A, 3 aps
 
 
Total number of data (n)
                                       7
Percentage of censored data
                                      0%
Number of non-censored data
                                       7
Lowest residue
                                     0.080
Highest residue
                                     0.647
Median residue
                                     0.172
Mean
                                     0.268
Standard deviation (SD)
                                     0.222
Correction factor for censoring (CF)
                                     1.000
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.647
- Mean + 4 SD
                                     1.155
- CF x 3 Mean
                                     0.805
Unrounded MRL
                                     1.155
 
                                       
Rounded MRL
                                      1.5
 
                                       
 High uncertainty of MRL estimate.
[Small dataset]

                               Residues (mg/kg)
                                       n
                                     0.080
                                       1
                                     0.088
                                       1
                                     0.172
                                       1
                                     0.502
                                       1
                                     0.264
                                       1
                                     0.127
                                       1
                                     0.647
                                       1

                                  Metaldehyde
                            Pea (Succulent Shelled)
                                      USA
                              1.0 lb ai/A, 3 aps
 
 
Total number of data (n)
                                       7
Percentage of censored data
                                      43%
Number of non-censored data
                                       4
Lowest residue
                                     0.050
Highest residue
                                     0.130
Median residue
                                     0.082
Mean
                                     0.080
Standard deviation (SD)
                                     0.031
Correction factor for censoring (CF)
                                     0.714
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.130
- Mean + 4 SD
                                     0.206
- CF x 3 Mean
                                     0.171
Unrounded MRL
                                     0.206
 
                                       
Rounded MRL
                                      0.2
 
                                       
 High uncertainty of MRL estimate.
[Small dataset]

                               Residues (mg/kg)
                                       n
                                     0.05
                                       3
                                    0.1295
                                       1
                                    0.08245
                                       1
                                    0.0947
                                       1
                                    0.1035
                                       1

                                  Metaldehyde
                             Pea (Pods with Seed)
                                      USA
                              1.0 lb ai/A, 3 aps
 
 
Total number of data (n)
                                       3
Percentage of censored data
                                      33%
Number of non-censored data
                                       2
Lowest residue
                                     0.050
Highest residue
                                     0.252
Median residue
                                     0.097
Mean
                                     0.133
Standard deviation (SD)
                                     0.105
Correction factor for censoring (CF)
                                     0.778
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.252
- Mean + 4 SD
                                     0.555
- CF x 3 Mean
                                     0.310
Unrounded MRL
                                     0.555
 
                                       
Rounded MRL
                                      0.6
 
                                       
 High uncertainty of MRL estimate.
[Small dataset]

                               Residues (mg/kg)
                                       n
                                   < 0.05 
                                       1
                                     0.097
                                       1
                                    0.2515
                                       1

                                  Metaldehyde
                                 Pea (Foliage)
                                      USA
                              1.0 lb ai/A, 3 aps
 
 
Total number of data (n)
                                       3
Percentage of censored data
                                      33%
Number of non-censored data
                                       2
Lowest residue
                                     0.050
Highest residue
                                     0.330
Median residue
                                     0.208
Mean
                                     0.196
Standard deviation (SD)
                                     0.140
Correction factor for censoring (CF)
                                     0.778
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.330
- Mean + 4 SD
                                     0.758
- CF x 3 Mean
                                     0.457
Unrounded MRL
                                     0.758
 
                                       
Rounded MRL
                                      0.8
 
                                       
 High uncertainty of MRL estimate.
[Small dataset and high level of censoring]

                               Residues (mg/kg)
                                       n
                                    0.050 
                                       1
                                     0.330
                                       1
                                     0.208
                                       1

                                  Metaldehyde
                                Clover (Forage)
                               Pacific NW - USA
                              0.8 lb ai/A, 2 aps
 
 
Total number of data (n)
                                       3
Percentage of censored data
                                      0%
Number of non-censored data
                                       3
Lowest residue
                                     0.053
Highest residue
                                     0.235
Median residue
                                     0.165
Mean
                                     0.151
Standard deviation (SD)
                                     0.092
Correction factor for censoring (CF)
                                     1.000
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.235
- Mean + 4 SD
                                     0.519
- CF x 3 Mean
                                     0.453
Unrounded MRL
                                     0.519
 
                                       
Rounded MRL
                                      0.6
 
                                       
 High uncertainty of MRL estimate.
[Small dataset and High level of censoring]

                               Residues (mg/kg)
                                       n
                                     0.165
                                       1
                                     0.053
                                       1
                                     0.235
                                       1

                                  Metaldehyde
                                 Clover (Hay)
                                      USA
                              0.8 lb ai/A, 2 aps
 
 
Total number of data (n)
                                       3
Percentage of censored data
                                      67%
Number of non-censored data
                                       1
Lowest residue
                                     0.050
Highest residue
                                     0.241
Median residue
                                     0.050
Mean
                                     0.114
Standard deviation (SD)
                                     0.110
Correction factor for censoring (CF)
                                     0.556
 
                                       
Proposed MRL estimate
 
 
                                       
- Highest residue
                                     0.241
- Mean + 4 SD
                                     0.553
- CF x 3 Mean
                                     0.189
Unrounded MRL
                                     0.553
 
                                       
Rounded MRL
                                      0.6
 
                                       
 High uncertainty of MRL estimate.
[High level of censoring]

                               Residues (mg/kg)
                                       n
                                    0.050 
                                       2
                                     0.241
                                       1