UNITED STA TES ENVIRONMENTA L PROTECTION AGENCY

MEMORANDUM Date : 5 / 1 8 /11 SUBJECT: Abamectin. Petition for

Subgroup 3 - 07A, Residue Data. PC Code: 122804 Decision No.: 436528 Petition No.: 0E7738 Risk Assessment Type: None T XR No.: None MRID No s .: 48135001, 48135002, 48135003 (see MRID Summary Table) FROM: Nancy

Dodd, Chemist Risk Assessment Branch Health Effects Division THROUGH: Leung Cheng, Senior Chemist

RAB3/HED (7509P) TO: Barbara Madden, RM#5

Registration Division (7505P) MRID Summary Table Study Type 860.1500 - Crop Field Trial 860.1500 - Crop Field Trial 860.1500 - Crop Field Trial N ote: This DER was originally prepared under contract by Versar, Inc. (6850 Versar Center, Springfield, VA 22151; submitted 12/21 /10). The DER has been reviewed by the Health Effects Division (HED) and revised to reflect current Office of Pesticide Programs (OPP) policies. Page 1 of 24

UNITED STA

TES ENVIRONMENTA L PROTECTION AGENCY WASHINGTON, D.C. 20460 OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

Petition for Tolerances/ Section 3 Registration on the Chives, and Dry

Beans . S ummary

of Anal yt ical Chemistry

and DP Barcode: 380795 Registration No. : 100 - 1351 , 100 - 898 Regulatory Action: Section 3 Regi stration Case No.: None CAS No.: 71751 - 41 - 2 48135002, (see MRID Summary

Table) 40 CFR: 180.449 Nancy Dodd, Chemist isk Assessment Branch III (RAB3) Health Effects Division (HED) (7509P) Leung Cheng, Senior Chemist

(7509P) Barbara Madden, RM#5 Registration Division (7505P)

MRID Comments 48135001 New DER; 48135001.der; 48135002 New DER; 48135002.der; 48135003 New DER; 48135003.der; ote: This DER was originally prepared under contract by Versar, Inc. (6850 Versar Center, Springfield, VA 22151; submitted

DER has been reviewed by the Health Effects Division (HED) and revised to reflect current Office of Pesticide UNITED STA

TES ENVIRONMENTA L PROTECTION AGENCY OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

the Bulb Onion ical Chemistry

and 898 , 100 - 1154 stration

48135001.der; Bulb onion 48135002.der; Chives 48135003.der; Dry Bean s ote: This DER was originally prepared under contract by Versar, Inc. (6850 Versar Center, Springfield, VA 22151; submitted

DER has been reviewed by the Health Effects Division (HED) and revised to reflect current Office of PesticidePage 2 of 24

Executive Summary Abamectin is a mixture of avermectin B 1 [a mixture of avermectins containing greater than or equal to 80% avermectin B 1a (5 - O - demethylavermectin A 1 ) and less than or equal to 20% avermectin B 1b (5 - O - demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A 1 )] and its delta - 8,9 - isomer. Abamectin is a natural fermentation product of the soil bacterium Streptomyces avermitilis. Abamectin is an insecticide/miticide used to control mites, leafminers, and other insects in commerciall y important crops. Abamectin acts as an insecticide b y int erfering with the nervous sy stem of the insect, causing the insect to become paral yz ed. Available mechanistic data indicate a neurotoxic mechanism of action, related to interference with GABA - mediated neurotransmission. In this petition (PP# 0E7738 ) , th e Interregional Research Project No. 4 ( IR - 4 ) has proposed label amendments for three products to include uses on the bulb onion subgroup 3 - 07A , chive s , and dry bean s . The products include Agri - Mek® 0.15 EC Miticide/In secticide (2% ai; EPA Reg No. 100 - 898 ), Agri - Mek® SC Miticide/In secticide (8% ai; EPA Reg No. 100 - 1351), and Epi - Mek® 0.15 EC Miticide/In secticide (2% ai; EPA Reg No. 100 - 1154). The products are to be applied as foliar sprays using ground and aerial (except chive) methods. The labels and Se ction B of the petition specify

a maximum seasonal rate of 0.056 lb ai/A for bulb onion, chive s , and dry bean s . The preharvest intervals (PHI s ) specified are 30 days for bulb onion and 6 day s for chives and dry beans. The SC ( suspension concentrate) label indicate s that applications to all crops are required to be made with an adjuvant. The emulsifiable concentrate ( EC ) labels indicate that an adjuvant is required for bulb onion s , but is only suggested for use with chives and dry bean s . Section B of the petition only specifies the use of non - ionic adjuvant with bulb onions (SC and EC labels). In conjunction with the proposed new uses , IR - 4, on behalf of the Agricultural Experiment Stations of FL , CO, TX, HI, OR, NY, ID, WA, CA and TN, has proposed the establishment of permanent tolerances for the combined residues of abamectin [ (10E,14E,16E) - (1R,4S,5 ′S ,6S,6′R,8R,12S,13S,20R,21R,24S) - 6 ′ - [(S) - sec - butyl] - 21,24 - dihydroxy- 5 ′,11,13,22 - tetramethyl - 2 - oxo - (3,7,19 trioxatetracyclo[15.6.1.14,8.020,24] pentacosa - 10,14,16,22 - tetraene) - 6 - spiro - 2 ′ - (5 ′,6′ - dihydro - 2 ′H -py ran) - 12 - yl2,6 - dideoxy- 4 - O - (2,6 - dideox y- 3 - O - methyl - α - L arabino - hexopy

ranos yl ) - 3 - O - methyl - α - L - arabino - hexopy ranoside ] in/on the following raw agricultural and processed commodities:

Onion, bulb, subgroup 3 - 07A ................................ .. 0.01 ppm Chive, fresh leaves ................................ ................... 0.01 ppm Chive, dried leaves ................................ ................... 0.07 ppm Bean, dry , seed ................................ ......................... 0.01 ppm Tolerances have been established in 40 CFR §180.449(a) for the combined residues of the insecticide avermectin B 1 [a mixture of avermectins containing greater than or equal to 80% avermectin B 1a (5 - O - demethyl avermectin A 1 ) and less than or equal to 20% avermectin B 1b (5 - O - demethyl - 25 - de(1 - methylprop yl ) - 25 - (1 - methylethyl) avermectin A 1 )] and its delta - 8,9 - isomer in/o n various plant and livestock commodities at levels ranging from 0.005 to 0.20 ppm. T ime -Page 3 of 24

limited tolerance s are established in 40 CFR §180.449(b) for residues of avermectin B 1 and its delta - 8 , 9 - isomer in/on onion, bulb at 0.005 ppm (to expire on 12/31/12 ) and in/on b ean, lima, seed at 0.005 ppm (set to expire on 12/31/1 3 ). The qualitative nature of the abamectin residues in plants is adequatel y understood based on metabolism studies on cottonseed, citrus, and celery. The available studies indicate that t he metabolism of abamectin in plants results in a complex mixture of residues. The majority of the terminal residue is composed of several unidentified polar degradates. The parent compound, its delta - 8,9 - isomer, and the alpha 8 - OH degradate have been identified in plants, with only the parent and its delta - 8,9 - isomer each accounting for at least 10% of the total residue. In citrus, the majority of the residue remained in the peel but a small amount translocated into the pulp. For the tolerance expression and risk assessment, the residues of concern in these crops are the parent c ompounds (avermectin B 1a and B 1b ) and their delta - 8,9 - isomers (also known as 8,9 - Z isomers). The qualitative nature of abamectin residues in ruminants is adequatel y understood based on a goat metabolism study . The residues of concern in ruminants for the tolerance expression and risk assessment are the parent compounds ( avermectin B 1a and B 1b ) and their delta - 8,9 - isomers. If the tolerances for residues in meat and milk need to be raised at some future time due to registration of abamectin on additional f eed items, the 24 - hydrox ym ethylmetabolite may need to be included in the tolerance expression and appropriate enforcement methods developed. Since no significant poultry feed items (as indicated in Table 1 Feedstuffs , June 2008) are associated with the proposed uses, no poultry metabolism study

is required. The results of a confined rotational crop study indicated that avermectin residues accumulated in some rotational crops at levels up to 10 - 12 ppb; however, the radioactivity was due to polar degradat es that were of little toxicological concern as compared to the parent compound avermectin B 1 and/or the delta - 8,9 - isomer. It is not likely that residues of concern will occur in rotational crops. Analy tical methods for enforcement of residues from the u se of abamectin are available in PAM II for citrus and processed fractions (Method I), ginned cottonseed (Method IA), and bovine tissues and milk (Method II). Method M - 073 and M - 936 - 95 - 2 have been validated by the Agency and submitted for inclusion in FDA ’s PAM II as enforcement methods (Memo, W. Wassell, PP#5E4556, 6/11/96). These five methods are adequate for enforcement of the tolerances on plants and livestock . The methods determine residues at limits of quantitation (LOQs) of 0.02 ppm for meat and m eat b yproducts and ≤0.01 ppm for other plant/livestock commodities . The 1990 Pestrak database indicates that abamectin and its metabolites are not recovered or not likely to be recovered b y FDA multiresidue methods. Therefore, the multiresidue methods cannot be used to determine residues for dietary exposure assessment and cannot be used as the primary enforcement method.Page 4 of 24

Storage stability

studies submitted with the previous petitions were deemed adequate and can be translated to support the storage durations and conditions of dry bulb onion s and chive s (fresh and dried) . For dry

bean s , the petitioner needs to submit the storage temperature for the samples collected in the crop field trial study . The submitted magnitude of the residue data for dry bulb onion, chive s , and dry bean s (except cowpea) are adequate pending label revisi ons . The conducted trials reflect the proposed use patterns , except regarding the use of adjuvants for chive s and dry bean s . Label revisions are required for the EC labels to remove the statement that adjuvants may be used for chive s and dry bean s since the residue data on chive s and dry bean s did not reflect use of adjuvants . The ChemSAC determined on 5/18/11 that the available bridging studies for the SC formulation on l eaf y vegetables, fruiting vegetables, cucurbit vegetables, citrus fruits, and pome fruits (DP#364734, N. Dodd, 1/21/10) can be translated to support use of the SC formulation on the bulb onion subgroup 3 - 07A, chive s , and dry bean s provided the use directio ns for the SC formulation always require use of a non - ionic surfactant or a horticultural oil in the spray mix and the preharvest intervals are ≥ 7 day s. Residue data for cowpea forage and hay must be submitted before cowpea can be included in the “bean, dry , seed” tolerance. An adequate processing study was conducted on chive s . Residues of abamectin concentrated in dried chive s (processing factor of 2.9x). Tolerance adjustment is required for dried chive s in order to reflect the appropriate tolerance level . Codex has recommended several MRLs for abamectin ( Pesticide Residues in Food - 1997, Part 1). The Codex residue definition (step 8/CXL) is the “sum of avermectin B 1a , avermectin B 1b , 8,9 - Z - avermectin B 1a and 8,9 - Z - avermectin B 1b ” for plants, and the “sum of avermectin B 1a and 8,9 - Z - avermectin B 1a ” for livestock commodities . The Codex limits of determination (equivalent to HED’s limits of quantitation, L OQs) for plant and livestock commodities are ≤0.01 ppm. (For plants, the L OQ ranges from 0.002 to 0.005 ppm for each of two peaks, one peak representing avermectin B 1a and its 8,9 - Z - isomer and the other peak representing avermectin B 1b and its 8,9 - Z - isomer) . For cattle meat, the Codex L OQ is 0.01 ppm. The tolerance expression in Canada for plants is “avermectin B 1a , avermectin B 1b , and the 8,9 - Z - isomers.” The tolerance expression in Mexico for plants is avermectina. Re gulatory Re commendations and Residue Chemistry Deficiencies HED has examined the residue chemistry database for abamectin . Pending submission of revised Sections B (see 860.1200 Directions for Use) and F (see 8 60.1550 Proposed Tolerances), there are no residue chemistry issues that would preclude granting conditional registration s of the emulsifiable conc entrate (EC) and suspension concentrate (SC) formulation s of abamectin and the following permanent tolerance s for abamectin:

Onion, bulb , subgroup 3 - 07A ................................ .. 0.01 ppm Chive, fresh leaves ................................ ................... 0.01 ppm Chive, dried leaves ................................ ................... 0.02 ppm Bean, dry , seed , except cowpea ............................... 0.01 ppmPage 5 of 24

Cowpea has been excluded from the tolerance for “bean, dry , seed” since residue data for cowpea forage and hay

must be submitted to support use on cowpea. As a condition of registration of the EC formulation, the petitioner needs to submit the storage temperature of the dry

bean samples from the crop field trial . A human health risk assessment is forthcoming. Note to PM: T he tolerance expression for abamectin in 40 CFR §180.449 (a) and (b) should be revised according to HED’s Interim Guidance on Tolerance Expressions (5/27/09, S. Knizner) to state: “ Tolerances are established for residues of abamectin, including its metabolites and degradates, in or on the commodities in the table below. Compliance with the tolerance levels specified below is to be determined by measuring only avermectin B 1 [a mixture of avermectins containing greater than or equal to 80% avermectin B 1a (5 - O- demethyl avermectin A 1 ) and less than or equal to 20% avermectin B 1b (5 - O- demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A 1 )] and its delta - 8,9 - isomer.” 860.1200 Directions for Use  Label revisions are required for the EC labels to remove the statement that adjuvants may be used on chives and dry bean s since the submitted crop field trials on chives and dry bean s do not reflect the use of an adjuvant.  The labels must be revised to specify a 7 - day PHI for chives and dry

bean s since most of the chive and dry

bean data reflect a 7 - day PHI.

 The amount (v/v) of the non - ionic surfactant and/or horticultural oil is required to be specified in the Directions for Use for each crop on the SC label and is required to be within the range of the amount (v/v) used in the available SC field trials (D3647 34, N. Dodd, 1/21/10) .  Cowpea must be removed from the label under dry bean since residue data for cowpea forage and hay

must be submitted to support use on cowpea. 860.1500 Crop Field Trials  The petitioner needs to submit the storage temperature of the dry bean samples from the crop field trial.  Residue data for cowpea forage and hay must be submitted before cowpea can be included in the bean, dry , seed tolerance. 860.1550 Proposed Tolerances  The petitioner should submit a revised Section F reflecting the recommended tolerance levels and correct commodity definitions as presented in Table 6. The proposed tolerance level for chives, dried leaves must be lowered from 0.07 ppm to 0.02 ppm. Cowpe a mustPage 6 of 24

be excluded from the dry bean seed tolerance since residue data for cowpea forage and hay must be submitted before cowpea can be included in the dry bean seed tolerance. Background Abamectin includes the combined residues of avermectin B 1 [a mixture of avermectins containing ≥80% avermectin B 1a (5 - O - demethylavermectin A 1 ) and ≤20% avermectin B 1b (5 - O demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A 1 )] and its delta - 8,9 - isomer. Abamectin is a natural fermentation product of the soil bacterium Streptomyces avermitilis. Itis used as an insecticide/miticide on crops for the control of mites, leafminers, and other insects, as a seed protectant against nematodes, and in veterinary medicine for treatment of intern al and external parasites and mites. The nomenclature and physicochemical properties of abamectin are presented below in Tables 1 and 2. Table 1. Test Compound Nomenclature. Compound

Common name a bamectin; avermectin B 1 Company experimental name MK- 0936 O O O

O C H 3 O H C H 3 O O H 3 C O O

O H C H 3 C H 3 O C H 3 O H O C H 3

C H 3 C H

3 O C H 3

O O O

O C H 3 O H C H 3 O O H 3 C O O

O H C H 3 C H 3 O C H 3 O H O C H 3

C H 3 C H 3 O C H 3 Avermectin B 1a

Avermect in B 1bPage 7 of 24

Table 1. Test Compound Nomenclature. IUPAC name mi xture of ≥ 80% ( 10E ,14E ,16E) - (1 R ,4 S,5' S,6 S,6'R ,8 R ,12 S,13 S,20R ,21 R ,24 S ) - 6' - [(S ) -sec butyl] - 21,24 - dihydroxy- 5',11,13,22 - tetramethyl - 2 - oxo - (3,7,19 - trioxatetracyclo[15.6.1.1 4,8 .0 20,24 ]pentacosa - 10,14,16,22 - tetraene) - 6 - spiro - 2' - (5',6' - dihydro 2'H - pyran) - 12 - yl 2,6 - dideoxy- 4 - O - (2,6 - dideoxy- 3 - O - methyl - α - L - arabino -hexopyranosyl) - 3 - O - methyl - α - L - arabino -hexopyranoside and ≤ 20% (10E ,14E ,16E ) - (1 R ,4 S,5' S,6 S,6'R ,8 R ,12 S,13 S,20R ,21 R ,24 S ) - 21,2 4 - dihydroxy- 6' - isopropyl - 5',11,13,22 - tetramethyl - 2 - oxo - (3,7,19 - trioxatetracyclo[15.6.1.1 4,8 .0 20,24 ]pentacosa - 10,14,16,22 - tetraene) - 6 - spiro - 2' - (5',6' - dihydro - 2'H - pyran) - 12 - yl 2,6 - dideoxy- 4 - O - (2,6 - dideoxy- 3 - O methyl - α - L - arabino -hexopyranosyl) - 3 - O - methyl - α - L - arabino -hexopyranoside CAS name avermectin B 1 CAS registry number 71751 - 41 - 2 End -use product s (EP s ) 0.15 lb ai/gal EC (Agri - Mek® 0.15 EC Miticide/Insecticide; EPA Reg. No. 100 - 898) 0.7 lb ai/gal SC (Agri - Mek® SC Miticide/Insecticide; EPA Reg. No. 100 - 1351 ) 0.15 lb ai/gal E C ( Epi - Mek® E C Miticide/Insecticide; EPA Reg. No. 100 - 1154 Table 2. Physicochemical Properties of the Technical Grade Abam ectin Parameter Value Reference 1 Melting point/range 155 - 157°C Accession No. 260785 pH not available Density 1.16 g/cm3 at 21°C Accession No. 260785 Water solubility (20°C) < 0.01 mg/mL in distilled water < 0.001 mg/mL in tap water < 0.001 mg/mL in buffer system pH 6, 7.4 & 9.0 < 0.001 mg/mL in 0.9% NaCl Accession No. 260785 Solvent solubility (mg/mL at 20°C) > 3 mg/mL in ethanol; >2 mg/mL in isopropyl myristate, chloroform, dimethylacetamide, dimethylformamide, glycerol formal & polyethylene gl ycol 400. Accession No. 260785 Vapor pressure at 25°C 1.5 x 10 - 9 hPa Accession No. 260785 Dissociation constant (pKa) Not available Octanol/water partition coefficient Log(KOW) 9.9 x 10 - 3 Accession No. 260785 UV/visible absorption spectrum not available 1 Product Chemistry data were reviewed by Leung Cheng (Accession No. 260785, RCB No. 388, 5/1/1986). 860.1200 Directions for Use The petitioner has submitted draft labels for Agri - Mek® 0.15 EC Miticide/Insecticide (2% ai; EPA Reg No. 100 - 898), Agri - Mek® SC Miticide/Insecticide (8% ai; EPA Reg No. 100 - 1351), and Epi - Mek® 0.15 EC Miticide/In secticide (2% ai; EPA Reg No. 100 - 1154). The formulations are being proposed b y IR - 4 for use on the bulb onion subgroup 3 - 07A , chives, and dry beans . All formulations are currently registered for use on a variety of crops. A summary of the proposed us e patterns is detailed in Table 3.Page 8 of 24 Table 3 . Summary of Directions for Use of Abam ectin . Applic. Timing, Ty pe, and Equip. Form

ulation [EPA Reg. No.] Applic.

Rate (lb ai/A) Max. No. Applic. per Season Max. Seasonal Applic. Rate (lb ai/A) PHI 1

(days) Use Directions and Limitations 2

Onion, bulb (Crop Subgroup 3 - 07A) ( onion, bulb including daylily, bulb; fritillaria, bulb; garlic, bulb; garlic, great- headed, bulb; garlic, serpent, bulb; lily, bulb; onion, Chinese, bulb; onion, pearl; onion, potato, bulb; shallot, bulb; cultivars, varieties, and/or hybrids of these ) Foliar spray (ground or aerial) 4,5 Agri - Mek® 0.15

EC Insecticide/Miticide [ EPA Reg. No. 100 - 898] Agri - Mek® SC Insecticide/ Miticide [ EPA Reg . No. 100 - 1351] Epi - Me k® 0.15 EC Insecticide/Miticide [ EPA Reg . No. 100 - 1154 ] 0.019 Not stated 0.056 30 Do not apply in less than 20 gallons of water/A with ground application equipme nt. Do not apply in less than 5 gallons of water/A with aircraft. Include a non - ionic surfactant commercially used on dry bulb onions . RTI 3 = 7 days. Adjuvant Requirement SC formulation: To avoid illegal crop residues, the SC formulations must always be mixed with a non - ionic activator type wetting, spreading and/or penetrating adjuvant. Do not us e binder sticker type adjuvants . ( See Use Information and Use Restrictions . ) EC formulation: Add a non - ionic activator ty pe wetting, spreading and/or penetrating adjuvant approved for use on bulb onion. Do not use binder sticker type adjuvants. Chives Foliar spray (ground) 4 Agri - Mek® 0.15

EC Insecticide/Miticide [ EPA Reg. No. 100 - 898] Agri - Mek® SC Insecticide/ Miticide [ EPA Reg . No. 100 - 1351] Epi - Me k® 0.15 EC Insecticide/Miticide [ EPA Reg . No. 100 - 1154 ] 0.019 Not stated 0.056 6 Apply as a foliar spray in a minimum of 20 gallons of water per acre. Adjuvant Requirement SC formulation: To avoid illegal crop residues, the SC formulations must always be mixed with a non - ionic activator type wetting, spreading and/or penetrating adjuvant. Do not use binder sticker type adjuvants . ( See Use Information and Use Restrictions . ) 6 RTI = 7 days. EC formulation: When necessary to improve the wetting of foliage and to smooth out sprayPage 9 of 24 Table 3 . Summary of Directions for Use of Abam ectin . Applic. Timing, Ty pe, and Equip. Form

ulation [EPA Reg. No.] Applic.

Rate (lb ai/A) Max. No. Applic. per Season Max. Seasonal Applic. Rate (lb ai/A) PHI 1

(days) Use Directions and Limitations 2

deposits, a nonionic surfactant is recommended . Beans, dry [ Cicer arietinum (chickpea, garbanzo bean); Lupinus spp. (including sweet lupine, white sweet lupine, white lupine, and grain lupine); Phaseolus spp. (including kidney bean, lima bean, mung bean, navy bean, pinto bean, snap bean and waxbean); Vicia faba (broad be an, fava bean); Vigna spp. (including adzuki bean, asparagus bean, blackeyed pea, catjang, Chinese longbean, cow pea, crowder pea, moth bean, mung bean, rice bean, southern pea, urd bean, and yardlong bean) ] Foliar spray (ground or aerial) 4,5 Agri - Mek® 0.15

EC Insecticide/Miticide [ EPA Reg. No. 100 - 898] Agri - Mek® SC Insecticide/ Miticide [ EPA Reg . No. 100 - 1351] Epi - Me k® 0.15 EC Insecticide/Miticide [ EPA Reg . No. 100 - 1154 ] 0.019 Not stated 0.056 6 Do not apply in less than 1 0 gallons of water/A with ground application equipme nt. Do not apply in less than 5 gallons of water/A with aircraft. Adjuvant Requirement SC formulation: To avoid illegal crop residues, the SC formulations must always be mixed with a non - ionic activator type wetting, spreading and/or penetrating adjuvant. Do not use binder sticker type adjuvants . ( See Use Information and Use Restrictions . ) 6 RTI = 6 days. EC formulation: A non - ionic activator type wetting, spreading and/or penetrating adjuvant approved for use on dry bean s and peas can be used to help improve control. Do not use binder sticker type adjuvants. 1 PHI = preharvest interval. 2 Onion, bulb - Make 2 consecutive applications then rotate to a chemistry ( pesticide ) with a different mode of action. Make at least 2 applications of a chemistry ( pesticide ) with a different mode of action before making additional applications. Do not make more than 2 sequential applications o f any other foliarly applied abamectin containing product. Chive s - Do not make more than 2 applications o f any foliarly applied abamectin containing product per single cutting (harvest). Dry beans - Do not make mo re than 2 sequential applications o f any foliarly applied abamectin containing product. 3 RTI =retreatment interval. 4 Do not apply through any type of irrigation system. 5 Aerial applications are not allowed in NY. 6 The use of an adjuvant is required on the Agri - Mek® SC Insecticide/Miticide label, but is not specified in the Section B use directions for chives and dry beans. Conclusions : The submitted labels for Agri - Mek® 0.15 EC Insecticide/Miticide (EPA Registration No. 100 - 898), Agri - Mek® SC Insecticide/ Miticide (EPA Registration No. 100 -Page 10 of 24

1351), and Epi - Mek® 0.15 EC Insecticide/Miticide (EPA Registration No. 100 - 1154) are adequate to allow evaluation of the residue data relative to the proposed uses. Label revisions are required for the EC labels to remove the statement that adjuvants may be used on chives and dry

bean s since the submitted crop field trials on chives and dry bean s do not reflect the use of an adjuvant. The ChemSAC determined on 5 /18/11 that the available bridging studies for the SC formulation on leafy vegetables, fruiting vegetables, cucurbit vegetables, citrus fruits, and pome fruits (DP#364734, N. Dodd, 1/21/10) can be translated to support use of the SC formulation on the bulb onion subgroup 3 - 07A, chive s , and dry bean s provided the use directions for the SC formulation always require use of a non - ionic surfactant or a horticultural oil in the spray mix and the preharvest intervals are ≥ 7 day s. The amount (v/v) of the non - ionic surfactant and/or horticultural oil is required to be specified in the Directions for Use for each crop on the SC label and is required to be within the range of the amount (v/v) used in the available SC field trials (D364734, N. Dodd, 1/21/10). The labels must be revised to specify a 7 - day PHI for chives and dry

beans since most of the chive and dry

bean data reflect a 7 - day PHI. Cowpea must be removed from the label under dry bean since residue data for cowpea forage and hay must be submitted to support use on cowpea. 860.1300 Nature of the Residue - Plants Residue Chemistry Memo : Dodd , N., 1/26/09, DP# D 316756 , PP# 0F6146 , Abamectin. Petition for the Establishment of Permanent Tolerances for Section 3 Registration on Pasture and Rangeland Grass, Stone Fruit Crop Group 12, Tree Nut Crop Group 14, Pistachio, and the Tuberous and Corm Vegetables Subgroup 1C; and Request for La bel Amendment to Add Aerial Application to Cucurbits, Fruiting Vegetables, and Leafy Vegetables on the Agri-Mek 0.15 EC Label. Summary of Analytical Chemistry and Residue Data. No new plant metabolism data were submitted with this tolerance petition. Metabolism studies on cottonseed, citrus, and celery (PP#s 5G3500, 5G3287, and 8F3649, respectivel y) have previously

been submitted. In addition, a report titled "Comparative Degradation of Avermectin B 1 a in Cotton L eaf, Citrus Fruit, Celery , and In Vitro " was also submitted (PP#9F3703, S. Willett, 12/15/89). The available studies indicate that the metabolism of abamectin in plants results in a complex mixture of residues. The majority of the terminal residue is composed of several unidentified polar degradates. The parent compound, its delta - 8,9 - isomer, and the alpha 8 - OH degradate have been identified in plants, with only the parent and its delta - 8,9 - isomer each accounting for at least 10% of the total residue. The polar degradates generated on citrus (7 - day PHI) and in vitro (30 hour sample) have been tested for toxicity and were found to be of no toxicological significance at the levels tested (TOX memos 7080 and 7081, W. Dy kstra, 3/15/89; PP#8F3592, F. Bo yd, 6/21/89; D203373, G. J. Herndon, 3/29/95) . In citrus, the majority of the residue remained in the peel but a small amount translocated into the pulp (MRID 161182).Page 11 of 24

Conclusions : The qualitative nature o f the abamectin residues in dry bulb onion, chive s and dry bean s is adequatel y understood bas ed on the metabolism studies on cottonseed, citrus, and celery . For the tolerance assessment and risk assessment, the residues of concern in these crops are the parent compounds (avermectin B 1a and B 1b ) and their delta - 8,9 - isomers (also known as 8,9 - Z is omers). 860.1300 Nature of the Residue - Livestock Residue Chemistry Memo DP# D 316756 , 1/26/09, N . Dodd; PP# 0F6146 No additional livestock metabolism data were submitted with this petition. A goat metabolism study has previously

been submitted (PP#7G3468, L . Cheng, 2/11/87; PP#9F3703, S Willett, 12/15/89). No poultry

metabolism study

has been submitted. Conclusions : The qualitative nature of abamectin residues in ruminants is adequatel y understood based on a goat metabolism study . The residues of concern in ruminants for the tolerance expression and risk assessment are the parent compounds (avermectin B 1a and B 1b ) and their delta - 8,9 - isomers. If the tolerances for residues in meat and milk need to be raised at some future time due to registration of abamectin on additional feed items, the 24 - hydroxy methyl metabolite may

need to be included in the tolerance expression and appropriate enforcement methods developed (PP#8F3592, F. Bo yd, 6/21/89; D P# 203373, G. J. Herndon, 3/29/95). Since no significant poultry feed items are associated with the proposed uses ( as indicated in Table 1 Feedstuffs , June 2008) , no poultry metabolism study

is required. 860.1340 Residue Analytical Methods Residue Chemistry Memo DP# D 316756 , 1/26/09, N . Dodd; PP# 0F6146 Plant commodities Enforcement methods for abamectin in plants are available in the Pesticide Analy tical Manual, Volume II ( PAM II), validated for citrus and processed fractions (Method I) and ginned cottonseed (Method IA ). Method M - 0 36.2 has been validated b y the Agency and submitted for inclusion in FDA’s PAM II as an enforcement method (Memo, W. Wassell, PP#5E45 6 6, DP# D225120, 6/11/96). EPA’s Anal ytical Chemistry L aboratory

evaluated Merck, Sharp, and Dohme Method 1009, Revision No. 2 (“HPL C - Fluorescence Determination for Avermectin B 1 and its Delta - 8,9 - Isomer in Citrus Fruit) in whol e oranges (PP#7G3468/FAP7H5518, Jay Wilner, 9/30/87). Data collection methods are described below.Page 12 of 24

Onion , bulb - The modified high performance liquid chromatography (HPLC) method ( Method M - 073.1) was used for determining residues of avermectin B 1a/8,9 - Z avermectin B 1a and avermectin B 1b in onion. Briefl y, residues in dry bulb onion samples were extracted with acetonitrile/1% phosphoric acid and then partitioned into hexane. The extract is purified and concentrated on an aminopropyl solid phase extraction column and the eff luent is derivatized with trifluoroacetic anhydride. Residues were analyzed by high performance liquid chromatography with fluorescence detection using the external standardization technique. The lowest limit of method validati on (LLMV) was 0.002 ppm for each anal yt e ( avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a) . This method is adequate for data collection based on acceptable method validation and concurrent method recovery data. Chive – Chive samples , fresh and dry , were extracted using method 936 - 95 - 2 and derivatized and anal yz ed for residues of avermectin B 1a/8,9 - Z avermectin B 1a and avermectin B 1b with m ethod M - 073. The methods were adequately validated prior to and in conjunction with the anal ys is of field trial samples. Briefly , residues in fresh and dry chive samples were extracted with acetonitrile, diluted with deionized water, and purified using solid phase extraction. The extract was th en derivatized with 1 - methylimidazole and trifluo roacetic anhydride. Residues were anal yz ed b y high performance liquid chromatography with fluorescence detection using the external standardization technique. The lowest limit of method validation (LLMV) w as 0.002 ppm for each anal yt e ( avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a) . This method is adequate for data collection based on acceptable method validation and concurrent method recovery data. Dry bean s - Dry

bean samples were anal yz ed f or residues of avermectin B 1a/8,9 - Z avermectin B 1a and avermectin B 1b/8,9 - Z avermectin B 1b with the modified anal ytical Merck M ethod M 036.2. Briefly , residues in dry bean samples were derivatized by mixing with 1 - methylimidazole and sitting on ice. Trifluoroacetic anhydride/acetonitrile ( TFAA/ACN ) was added to the samples, mixed, and brought to volume with ACN. The samples were centrifuged and anal yz ed by high performance liquid chromatography with fluorescence detection using the external standardi zation technique. The lowest limit of method validation (LLMV) was 0.002 ppm for each anal yt e ( avermectin B 1a , 8,9 - Z avermectin B 1a , and avermectin B 1b ) . This method is adequate for data collection based on acceptable method validation and concurrent met hod recovery data. Livestock Commodities An anal ytical enforcement method for abamectin in bovine tissues and milk is available in the Pesticide Analy

tical Manual ( PAM II), designated as Method II. EPA’s Anal ytical Chemistry L aboratory

evaluated Merck, Sharp, and Dohme Method 32A (“HPL C - Fluorescence Assay for Avermectin B 1a , B 1b , and the Avermectin B 1a Delta - 8,9 - I somer in Bovine Tissues and Milk”) in milk, beef liver, and beef muscle (PP#8F3592, DEB Nos. 3929 and 3920, V. Frank Bo yd , Ph.D., 9/2/ 88 ).Page 13 of 24

Conclusions : Adequate enforcement methods f or abamectin in pl ant and livestock commodities are available in PAM II . The methods have been validated for citrus and processed fractions (Method I), ginned cottonseed (Method IA), and bovine tissues and milk (Method II). These methods determine residues at limits of quantitation (LOQs) of 0.02 ppm for meat and meat by products and ≤0.01 ppm for other plant/livestock commodities. The limit of detection (LOD) of the methods for plant and livestock commodities is 0.001 ppm for each anal yt e, equivalent to 0.002 ppm for two anal yt es. The plant methods described above are adequate for data collection . 8 60.1360 Multiresidue Methods Residue Chemistry Memo DP# D 316756 , 1/26/09, N . Dodd; PP# 0F6146 The 1990 Pestrak database indicates that abamectin and its metabolites are not recovered or not likely to be recovered b y FDA multiresidue methods. Therefore, the multiresidue methods cannot be used to determine residues for dietary exposure assessment and cannot be used as the primary enforcement method. 860.1380 Storage Stability Residue Chemistry Memo DP# D 316756 , 1/26/09, N . Dodd; PP# 0F6146 Herndon, G.J., 3/29/95, DP# D203373, PP#4F04354. Abamectin (Avermectin B1) for Use in/on the Cucurbit Crop Group (Cucumbers, Melons, and Squash). Evaluation of Analytical Methodology and Residue Data.(MRIDs# 432038 - 01 (8 volumes), and 432286- 01 (1 volume). CBTS# s 13706 and 13707. The maximum storage intervals of the residue samples were 208 day s (6.8 months) for dry bulb onions, 992 day s (32.6 months) for chives , and 422 day s (13.9 months) for dry bean s . The dry bulb onion and chives were stored frozen at - 20° C . The storage temperature of the dry bean samples was not provided. No storage stability

studies h ave been submitted with this petition. However, the available storage stability

data (D P# 203373, G. J. Herndon, 3/29/95) showed that avermectin B 1a , avermectin B 1b, , and 8,9 - Z avermectin B 1a are stable under frozen storage for 24 months in celery , strawbe rries, and tomatoes; 29 months in oranges, lemons, and grapefruit; and 35 months in pears. The data (D P# 203373) also show that B 1a is stable in cottonseed for 14 months. Storage stability

data on Bahia grass also indicated that no significant degradation of avermectin B 1a occurred in grass samples stored at - 20°C for at least 5.6 months (MRID 161182; TRID 350120016). The storage stability data can be translated to dry bulb onions, chives, and dry bean s . Conclusions : The available storage stability data support the storage conditions and intervals of samples from all of the submitted field trials ; however, the storage temperature of the dry bean samples must be submitted.Page 14 of 24

860.1400 Water, Fish, and Irrigated Crops Residues in water, fish, and irrigated crops are not pertinent to the proposed uses of this petition. 860.1460 Food Handling Residues in food handling establishments are not pertinent to the proposed uses o f this petition. 860.1480 Meat, Milk, Poultry, and Eggs Residue Chemistry Memo DP# D 316756 , 1/26/09, N . Dodd; PP# 0F6146 Based on the Table 1 Feedstuffs (June 2008) , no feed items are assoc iated with the current petition ; therefore, the established livestock tolerances need not be reassessed for the purpose of this petition. 860.1500 Crop Field Trials DER References: 4 8135001 .der ( onion, bulb ) , 48135002 .der ( chives, fresh) , 48135003 .der (beans, dr y) IR- 4 has submitted field trial data on dry bulb onion, chives (fresh and dried), and dry beans supporting the proposed uses of abamectin ( EC and SC formulations) . The results from these field trials are discussed below and the residue data are summarized in Table 4 . T able 4. Summary of Residue Data from Crop Field Trials with an Abamectin Formulation (EC). Commodity Total

Applic. Rate (lb ai/A) PHI

(days) Residue Levels (ppm)

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

Total Combined Residues Dry bulb onion (proposed use = 0.056 lb ai/A total application rate, 30 - day PHI) Dry bulb onion 0.0567 -

0.0767 29 - 31 16 <0.004 0.0046 0.0043 0.004 0.0040 0.0002

Chive (proposed use = 0.056 lb ai/A total application rate, 6 - day PHI) Fresh chive leaves 0.057 - 0.059 5 - 7 6 <0.004 0.004 5 0.0042 0.004 0.0041 0.0

Bean, dry (proposed use = 0.056 lb ai/A total application rate, 6 - day PHI) Bean, dry 0.054 - 0.061 5 - 7 24 <0.004 0.006 0.005 0.004 0.0041 0.0Page 15 of 24

Onion, bulb IR- 4 submitted field trial data for abamectin on onion (dry bulb). Abamectin is a mixture of avermectins, including avermectin B 1a (~80% ) and avermectin B 1b (~20%). Eight onion field trials were conducted in the United States during the 2000 - 2001 growing season in NAFTA Zones 1 (NY; 1 trial), 5 (OH; 1 trial), 6 (TX; 1 trial), 8 (CO; 1 trial), 10 (CA and NM; 2 trials), 11 (WA ; 1 trial), and 12 (OR; 1 trial). At each test location three to four applications of an EC formulation of abamectin (Agri - Mek 0.15 EC) were made to the treatment p lots as a broadcast or directed foliar application at a target rate of 0.019 lb ai/A per application, for a total seasonal rate of 0.057 lb ai/A. Actual total application rates ranged from 0.0567 - 0.0767 lb ai/A. A fourth application was made to the CA trial site only as cooler than average weather conditions slowed bulb development and delayed the harvest. The re - treatment interval (RTI) was 6 to 8 days, except for the fourth application at the CA site which had a RTI of 34 day s. A commonly used non - ionic surfactant was applied at the maximum label rate at each application at each trial site. Duplicate control and treated samples of mature dry bulb onion were harvested from each plot 30±2 day s following the last application. Onion samples were analyzed for residues of avermectin B 1 and its isomer 8 ,9 - Z avermectin B 1 using Sy ngenta Crop Protection’s method M - 073.1, utilizing HPL C with fluorescence detection and the external standardization technique . The method anal yz es combined residues of avermectin B 1a and 8,9 - Z avermectin B 1a . The same is true for avermectin B 1b ; however, residues for 8,9 - Z avermectin B 1b are not reported as they were too small to be detected and not considered to be of consequence to the study. The method was adequatel y validated prior to and in conjunction with the analysis of the field trial samples , using untreated samples fortified separately at 0.002 and 0.005 ppm or 0.002 and 0.004 ppm with avermectin B 1a and avermectin B 1b , respectivel y. The LLMV was 0.002 ppm for each anal yt e (avermectin B 1a/ 8,9 - Z avermectin B 1a and avermectin B 1b ). The LOD and LOQ were calculated as 0.0003 ppm and 0.0009 ppm, respectivel y, for avermectin B 1a and as 0.0004 ppm and 0.0011 ppm, respectively , for avermectin B 1b . The L OD and LOQ were not calculated for 8,9 - Z avermectin B 1a because the number of recoveries at the LLMV was not sufficient for the calculations. The storage duration from harvest to extraction for anal ys is was 26 - 208 day s (0. 85 - 6.8 months) for dry bulb onion . Samples were anal yz ed within 4 day s of extraction. Available data show that avermectin B 1a , avermectin B 1b, , and 8,9 - Z avermectin B 1a are stable under frozen storage for 24 months in celery , strawberries, and tomatoes; 29 months in oranges, lemons, and grapefruit; and 35 months in pears. The data also show that B 1a is stable in cottonseed for 14 months (D203373, G. J. Herndon, 3/29/95 ). These data can be translated to onions and are adequate to validate the storage interval and conditions for the samples anal yz ed as part of the current study . Following 3 - 4 foliar application s of abamectin at a total seasonal rate of 0.0567 - 0.0767 lb ai/A , avermectin B 1a and 8,9 - Z avermectin B 1a residues in/on dry bulb onion at 29 - 31 day s PHI were <0.0 02 - 0.0 026 ppm . Avermectin B 1b residues in/on dry bulb onion at PHIs of 29 - 31 day s were not detected above the LLMV . Total combined residues in/on dry bulb onion at PHI s of 29 - 31 days were <0.0 04 - 0.0 046 ppm .Page 16 of 24

Conclusions : The number and locations of the dry bulb onion crop field trials are in accordance with OPPTS 860.1500. The field trials reflect the proposed use pattern, including the use of an adjuvant in all trials. The field trials were conducted with an EC formulation . The ChemSAC determined on 5/18/11 that the available bridging studies for the SC formulation on leafy vegetables, fruiting vegetables, cucurbit vegetables, citrus fruits, and pome fruits (DP#364734, N. Dodd, 1/21/10) can be translated to support use of the SC formulation on the bulb onion subgroup 3 - 07A prov ided the use directions for the SC formulation alway s require use of a non - ionic surfactant or a horticultural oil in the spray mix and the preharvest intervals are ≥ 7 days. The residue data for dry

onion bulbs were not entered into the tolerance spreadsheet since >15% of treated samples bore residues below the LOQ. For the purpose of setting tolerances, HED will rely on the maximum residues observed in/on the treated commodities which were 0. 0046 ppm . Based on these data, HED recommends a tolerance of 0.01 ppm. Chives (fresh and dried) IR- 4 submitted field trial data for abamectin on chives (fresh and dry leaves). Three chive field trials were conducted between 1999 and 2001 in NAFTA Zones 2 (NJ and MD; 2 trials) and 11 (WA; 1 trial). At each test location three applications of an EC formulation of abamectin (Agri Mek 0.15 EC) were made to the treatment plots as a foliar broadcast application at a target rate of 0.019 lb ai/A per application, for a total sea sonal rate of 0.057 lb ai/A. The re - treatment interval was 5 to 7 days. An adjuvant was not used for any of the applications. Duplicate control and treated samples of mature fresh chive leaves were harvested from each plot at a PHI of 6 ± 1 days . An additional fresh chive harvest was conducted 13 day s after the final application at the WA trial site. At this site, one control and one treated sample of fresh chive s were also collected 7 days after the final application and dried in a drying cabinet for 2 day s. Chive samples were analyzed for residues of avermectin B 1 and its isomer 8 ,9 - Z avermectin B 1 using Sy ngenta Crop Protection’s method M - 073. The method use s HPL C with fluorescence detection and the external standardization technique . The method analyzes combined residues of avermectin B 1a and 8,9 - Z avermectin B 1 a . The same is true for avermectin B 1b . The method was adequatel y validated prior to and in conjunction with the analysis of the field trial samples . The LLMV was 0.002 ppm for each anal yt e ( avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a) . The LOD and LO Q were not calculated for avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a because the number of recoveries at the LLMV was not sufficient for the calculations. The storage duration from harvest to extraction for anal ys is was 246 - 992 day s (8.1 - 32.6 months) for fresh chive leaves and 644 - 671 day s (21.2 - 22.1 months) for dry chive leaves . Analy sis took place within 1 day

of extraction. Available data show that avermectin B 1a , avermectin B 1b, , and 8,9 - Z avermectin B 1a are stable under frozen storage for 24 months in celery , strawberries, and tomatoes; 29 months in oranges, lemons, and grapefruit; and 35 months in pears. The data also show that B 1a is stable in cottonseed for 14 months (D203373, G. J. Herndon, 3/29/95 ). ThesePage 17 of 24

data can be translated to chives and are adequate to validate the storage interval and conditions for the samples anal yz ed as part of the current study . Following three foliar broadcast application s of abamectin at a total seasonal rate of 0.057 - 0.059 lb ai/A , avermectin B 1a and 8,9 - Z avermectin B 1a residues in/on fresh chive leaves at PHIs of 5 - 7 days were <0.0 02 - 0.0 02 5 ppm . Avermectin B 1b and 8,9 - Z avermectin B 1b residues were not detected above the LLMV; total combined residues were <0.0 04 - 0.0 04 5 ppm . At the WA site, avermectin B 1a and 8,9 - Z avermectin B 1a residues declined from an average of 0.002 ppm at a 7 - day PHIto <LLMV at the 13 - day PHI. Avermectin B 1b and 8,9 - Z avermectin B 1b residues were not detected in the samples at the 7 - day or 13 - day

PHI . Aver

mectin B 1a and 8,9 - Z avermectin B 1a residues in/on dried leaves prepared from fresh chives at a 7 - day PHI were 0.0 10 ppm . Avermectin B 1b and 8,9 - Z avermectin B 1b residues were not detected above the LLMV . Conclusions : For fresh chives , the number and locations of the chive crop field trials are in accordance with OPPTS Guideline 860.1500. The field trials, which were conducted with an EC formulation, reflect the proposed use pattern, including application rate and PHI . An adjuvant was not used in the field trials. Lab el revisions are required for the EC labels to remove the statement that adj uvants may be used on chives since the submitted chive field trials do not reflect the use of an adjuvant. Also, the labels must be revised to specify a 7 - day PHI for chives since most of the chive data reflect a 7 - day PHI. The ChemSAC determined on 5 /18/11 that the available bridging studies for the SC formulation on leafy vegetables, fruiting vegetables, cucurbit vegetables, citrus fruits, and pome fruits (DP#364734, N. Dodd, 1/21/10) can be translated to support use of the SC formulation on chives p rovided the use directions for the SC formulation alway s require use of a non - ionic surfactant or a horticultural oil in the spray mix and the preharvest intervals are ≥ 7 day s. The residue data for fresh chives were not entered into the tolerance spre adsheet since >15% of treated samples bore residues below the LOQ. For the purpose of setting tolerances, HED will rely on the maximum residues observed in/on the fresh chives which were 0.004 5 ppm . Based on these data, HED recommends a tolerance of 0.01 ppm. Bean s , Dry IR- 4 submitted field trial data for abamectin on dry beans. Twelve bean field trials were conducted during the 1999 growing season in NAFTA Zones 1 (OH; 2 trials), 2 (NJ; 1 trial), 5 (ND and WI; 5 trials), 10 (CA; 1 trial), and 11 (ID and WA; 3 trials). At each test location , three applications of an EC formulation of abamectin (Agri - Mek 0.15 EC) were made to the treatment plots as a foliar (broadcast or directed) application at a target rate of 0.019 lb ai/A per application, for a tot al seasonal rate of 0.057 lb ai/A. The re - treatment interval was 5 to 9 day s. An adjuvant was not used for any of the applications. Duplicate control and treated samples of mature dry

bean seeds were harvested from each plot at a 6±1 day PHI . Bean samples were anal yzed for residues of avermectin B 1 and its isomer 8,9 - Z avermectin B 1 using Merck Method M - 036.2, Revision 2. The method uses HPL C with fluorescence detectionPage 18 of 24

and the external standardization technique . The method anal yz es combined residues of avermectin B 1a and 8,9 - Z avermectin B 1a . The same is true for avermectin B 1b . The method was adequatel y validated prior to and in conjunction with the analysis of the field trial samples . The LLMV was 0.002 ppm for each anal yt e (avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a). The LOD and LO Q were 0.0006 ppm and 0.0019 ppm, respectivel y, for avermectin B 1a and 0.0007 ppm and 0.0022 ppm, respectivel y, for 8,9 - Z avermectin B 1 a . The LOD and LOQ were not calculated for avermectin B 1 b beca use the number of recoveries at the LLMV was not sufficient for the calculations. The maximum storage duration from harvest to extraction for anal ys is was 422 day s (13.9 months) for dry

bean s . Analysis took place between 0 and 9 day s after extraction. Available data show that avermectin B 1a , avermectin B 1b, , and 8,9 - Z avermectin B 1a are stable under frozen storage for 24 months in celery , strawberries, and tomatoes; 29 months in oranges, lemons, and grapefruit; and 35 months in pears. The data also sho w that B 1a is stable in cottonseed for 14 months (D203373, G. J. Herndon, 3/29/95 ). These data can be translated to dry beans . P ending submission of the storage temperature at the analy tical laboratory , the data are adequate to validate the storage interval and conditions for the samples anal yz ed as part of the current study . Following three foliar application s of abamectin at a total seasonal rate of 0.054 - 0.061 lb ai/A , avermectin B 1a and 8,9 - Z avermectin B 1a residues in/on dry bean s at PHIs of 5 - 7 day s were <0.0 02 - 0.0 04 ppm ; only

one replicate had residues detected above the LLMV. Avermectin B 1b and 8,9 - Z avermectin B 1 b residues in/on dry bean s at 5 - 7 day s PHI were not detected above the LLMV . Total combine d residues in/on dry bean s at PHI s of 5 - 7 day s were <0.0 04 - 0.0 06 ppm . Conclusions : For dry

bean s , the number of the crop field trials are in accordance with OPPTS 860.1500. The location of the crop field trials differed slightly from OPPTS 860.1500 . The petitioner is short two field trials in Zone 7 and one each in Zones 8 and 9 but submitted extra field trials in Zones 1, 2, and 11. The location of the trials is adequate. The field trials, which were conducted with an EC formulation, reflect the proposed use pattern, including application rate and PHI. An adjuvant was not used in the field trials. The EC label indicates than an adjuvant can be used with the applications, but is not required . Label revisions are required for the EC labels to remov e the statement that adjuvants may be used on dry

bean s since the submitted dry

bean field trials do not re flect the use of an adjuvant. The labels must be revised to specify a 7 - day PHI for dry

bean s since most of the dry bean data reflect a 7 - day PHI. The petitioner should also submit the storage temperature of the dry bean samples. Residue data for cowpea forage and hay

must be submitted before cowpea can be included in the bean, dry , seed tolerance. The ChemSAC determined on 5/18/11 that the availabl e bridging studies for the SC formulation on leafy vegetables, fruiting vegetables, cucurbit vegetables, citrus fruits, and pome fruits (DP#364734, N. Dodd, 1/21/10) can be translated to support use of the SC formulation on dry bean s provided the use direc tions for the SC formulation always require use of a non - ionic surfactant or a horticultural oil in the spray mix and the preharvest intervals are ≥ 7 day s. The residue data for dry

bean s were not entered into the tolerance spreadsheet since >15% of th e treated samples bore residues below the LOQ. For the purpose of setting tolerances, HED willPage 19 of 24

rely on the maximum residues observed in/on the dry beans which were 0.006 ppm . Based on these data, HED recommends a tolerance of 0.01 ppm. 860.1520 Processed Food and Feed Chive DER Reference : 48135002.der.doc A processing study with abamectin on chive s was submitted. The sample used for processing was generated from a trial conducted in WA during the 2000 growing season. Chives were harvested 7 days following the last of three foliar airblast applications of an EC formulation of abamectin (Agri - Mek 0.15 EC) for a total rate of 0.059 lb ai/A (~ 1x the maximum proposed seasonal rate). The harvested chive s were dried in a drying cabinet for 2 day s. Chive samples were analyzed for residues of avermectin B 1 and its isomer 8 ,9 - Z avermectin B 1 using Sy ngenta Crop Protection’s method M - 073. The method uses HPL C with fluorescence detection and the exter

nal standardization technique . The method analyzes combined residues of avermectin B 1a and 8,9 - Z avermectin B 1 a . The same is true for avermectin B 1b . The method was adequatel y validated prior to and in conjunction with the analysis of the field trial samples . The LLMV was 0.002 ppm for each anal yt e ( avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a) . The LOD and LOQ were not calculated for avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a because the number of recoveries at the LLMV was not sufficient for the calculations. The maximum storage duration from harvest to extraction for anal y sis was 636 day s ( 20.9 months) for fresh chives and 671 days ( 22.1 months) for dried chive s . Analy sis took place within 1 day

of extraction. Available data show that avermectin B 1a , avermectin B 1b , and 8,9 - Z avermectin B 1a are stable under frozen storage for 24 months in celery , strawberries, and tomatoes; 29 months in oranges, lemons, and grapefruit; and 35 months in pears. The data also show that B 1a is stable in cottonseed for 14 months (D203373, G. J. Herndon, 3/29/95). These data can be translated to chives and are adequate to validate the storage interval and conditions for the samples anal yz ed as part of the current study . In/on fresh chives, avermectin B 1a and 8,9 - Z avermectin B 1a residues were an average of 0.002 1 ppm and avermectin B 1b and 8,9 - Z avermectin B 1b residues were not detected above the LLMV . Total combined residues were an average of 0.004 1 ppm. Residue in the dried chive sample was 0.010 ppm for avermectin B 1a and 8,9 - Z avermectin B 1a , <0.002 ppm for avermectin B 1b , and 0.012 ppm for total combined residues (resulting in a processing factor of 2.9x) . No theoretical concentration factors are available for dried herbs.Page 20 of 24

Table 5. Residue Data fromChive Processing Study with Abam ectin. RAC Processed Commodity Total Rate (lb a.i./A) PHI

(days) Residues (ppm) Processing Factor 1 Avermectin B 1a and 8,9 -Z Avermectin B 1a Chive Fresh chive (RAC) 0.059 7 0.00216, <0.002 (avg. 0.0021) -- Dried chive 0.010 --

Avermectin B 1 b Chive Fresh chive (RAC) 0.059 7 <0.002, <0.002 (avg. <0.002) -- Dried chive <0.002 --

Total Combined Residues Chive Fresh chive (RAC) 0.059 7 0.00416, <0.004 (avg. 0.0041) -- Dried chive 0.012 2.9 1 Processing factor = residue in processed sample/average residue in unprocessed RAC sample. NC = not calculated. Conclusions : The chive processing study is acceptable to satisfy

data requirements. Residues of abamectin concentrated in the dried chive sample (2.9 x) f ollowing processing of the RAC ( fresh chives ) . Residues were only slightl y above the LOQ in one RAC sample and below the LOQ in the second RAC sample . These data suggest that a tolerance is needed for dried chives . The maximum expected residue of abamectin in dried chive s , resulting from the proposed use, is 0.012 ppm. This value was calculated b y multiplying the concentration factor of 2.9 x by the HAFT r esidue of 0.0042 ppm (see Table 4 ). The petitioner is required to submit a revised Section F to propose a tolerance of 0.02 ppm for residues of abamectin in/on “ chive, dried leaves ”. 860.1650 Submittal of Analytical Reference Standards The anal ytical reference standards for abamectin ( avermectin B 1 a and avermectin B 1 b ) have been submitted to the USEPA National P esticide Standards Repository . Anal ytical standards have expired for 8,9 - Z avermectin B 1a (NOA427011) and 8a - hydrox y avermectin B 1a (NOA 448112). The petitioner should submit updated Certif icate s o f Anal ys is or n ew material for these standards [Source: Personal Communication between T. Cole of the Anal ytical Chemistry Branch/Biological and Economic Anal ys is Division (ACB/BEAD ) and Versar, 12/20/2010] .Page 21 of 24

860.1850 Confined Accumulation in Rotational Crops and 860.1900 Field Accumulation in Rotational Crops Residue Chemistry Memo DP# D 316756 , 1/26/09, N . Dodd; PP# 0F6146 No rotational crop studies were submitted with this petition. Review of the results of the confined rotational crop study indicated that avermectin residues accumulated in some rotational crops at levels up to 10 - 12 ppb. However, the radioactivity was due to polar degradates that were of little toxicological concern as compared to the parent compound avermectin B 1 and/or the delta - 8,9 - isomer (Memo, P. Mastradone, 4/24/88). Therefore, field rotational crop studies are not required (PP#7F3500, PP#8F3592, and PP#5E4566, DP #s : D230333, D230352, and D230880, G . Herndon, 1/10/97). 860.1550 Proposed Tolerances HED has determined that the nature of the residue in plants and livestock is adequatel y understood. The residues of concern in plant and livestock commodities are the combined residues of avermectin B 1 [ ≥80% avermectin B 1a (5 - O - demethyl avermectin A 1 ) and ≤20% avermectin B 1b (5 - O - demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A 1 )] and its delta - 8,9 - isomer for tolerance and risk assessment. The petitioner has proposed the establishment of permanent tolerances for the combined residues of abamectin: (10E,14E,16E) - (1R,4S,5 ′S ,6S,6′R,8R,12S,13S,20R,21R,24S) - 6 ′ - [(S) - sec - butyl ] - 21,24 - dihydrox y- 5 ′,11,13,22 - tetramethyl - 2 - oxo - (3,7,19 trioxatetracyclo[15.6.1.14,8.020,24]pentacosa - 10,14,16,22 - tetraene) - 6 - spiro - 2 ′ - (5 ′,6′ - dihydro 2 ′H -py ran) - 12 - yl2,6 - dideoxy- 4 - O - (2,6 - dideox y- 3 - O - methyl - α - L - arabino - hexopy ranos yl ) - 3 - O methyl - α - L - arabino - hexopy ranoside in/on the following raw agricultural and processed commodities: Onion, bulb, subgroup 3 - 07A ................................ .. 0.01 ppm

Chive, fresh leaves ................................ ................... 0.01 ppm Chive, dried leaves ................................ ................... 0.07 ppm Bean, dry , seed ................................ ......................... 0.01 ppm An adequate number of field trials at ~1x the proposed use rate are available for the RACs of the bulb onion subgroup 3 - 07A, chive s , and dry bean s . The residue data were not entered into the tolerance spreadsheet because >15% of the treated samples bore residues below the LOQ. For the purpose of setting tolerances, HED will rely on the maximum residues. An adequate processing study was conducted on chives . Residues of abamectin concentrated in the dried chive sample (2.9x) following processing of the RAC (fresh chives). The processing study indicated that a tolerance of 0.02 ppm would be adequate for chives, dried leaves .Page 22 of 24

There are no Codex, Canadian, and Mexican maximum residue limits (MRLs) /tolerances on the bulb onion subgroup 3 - 07A, chive, or dry bean as indicated in Appendix 1. Codex has recommended several MRLs for plant and cattle commodities ( Pesticide Residues in Food - 1997, Part 1). The Codex residue definition (step 8/CXL) is the “sum of averme ctin B1a, avermectin B1b, 8,9 - Z - avermectin B1a and 8,9 - Z - avermectin B1b ” for plants, and the “sum of avermectin B1a and 8,9 - Z - avermectin B1a” for livestock commodities. The tolerance expression in Canada for plants is “ avermectin B1 (a mixture of avermectins containing greater than or equal to 80% avermectin B1a (5 - O - demethyl avermectin A1a) and less than or equal to 20% avermectin B1b (5 - O - demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A1a) and its delta - 8,9 - isomer). ” A tolerance summary for abamectin is presented in Table 6 . The petitioner should submit a revised section F reflecting the recommended tolerance levels as presented in Table 6 . The proposed tolerance level for chives, dried leaves must be lowered from 0.07 ppm to 0.02 ppm . Cowpea must be excluded from the dry bean seed tolerance since residue data for cowpea forage and hay must be submitted before cowpea can be included in the dry bean seed tolerance. Table 6 . Tolerance Summary for Abam ectin

Commodity Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments ( correct commodity

definition) Onion, bulb, subgroup 3 - 07A 0.01 p p m (0.005 ppm established time limited tolerance on onion, bulb to expire on 12/31/12) 0.01 ppm

Chive, fresh leaves 0.01 ppm 0.01 ppm Chive, dried leaves 0.07 ppm 0.02 ppm Bean, dry, seed 0.01 ppm 0.01 ppm Bean, dry, seed, except cowpeaPage 23 of 24

References DP#: 379892 Subject: Abamectin. Amendment of Agri - Mek® SC Label to Add More Crops Currently

on Agri - Mek 0.15 EC Label. From: Nancy Dodd To: John Hebert/Thomas Harris Date: 9/28/10 MRID: None DP#: 316756 Subject: Abamectin. Petition for the Establishment of Permanent Tolerances for Section 3

Registration on Pasture and Rangeland Grass, Stone Fruit Crop Group 12, Tree Nut Crop Group 14, Pistachio, and the Tuberous and Corm Vegetables Subgroup 1C; and Request for Label Amendm ent to Add Aerial Application to Cucurbits, Fruiting Vegetables, and Leafy Vegetables on the Agri - Mek 0.15 EC Label. Summary of Anal ytical Chemistry

and Residue Data. From: Nancy

Dodd To: John Hebert Date: 1/26/09 MRIDs: 4509670 2, 45 09670 3, 4509670 4, 4509670 5, 4509670 7, 4509670 8, 4509670 9 DP#: 203373 Subject: PP#4F04354. Abamectin (Avermectin B1) for Use in/on the Cucurbit Crop Group

(Cucumbers, Melons, and Squash). Evaluation of Analy tical Methodology and Residue Data . CBTS# s 13706 and 13707. From: G. J. Herndon To: George LaRocca/Linda Arrington Date: 3/29/95 MRIDs: 432038 - 01 (8 volumes) and 432286 - 01 (1 volume) Attachments: Appendix I - International Residue Limit Status sheet Template Version September 2005Page 24 of 24

Appendix I - 

### International Residue Limits

Abamectin ( PC Code 122804 ; 03/31/2011 ) Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico Codex 40 CFR 180.449: Plant/Livestock: sum of avermectin B 1 (a mixture of avermectins containing greater than or equal to 80% avermectin B 1a (5 - O - demethyl avermectin A 1 ) and less than or equal to 20% avermectin B 1b (5 - O - demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A 1 )) and its delta - 8,9 - isomer avermectin B 1 (a mixture of avermectins containing greater than or equal to 80% avermectin B 1a (5 - O - demethyl avermectin A 1a) and less than or equal to 20% avermectin B 1b (5 - O demethyl - 25 - de(1 - methylpropyl) - 25 - (1 - methylethyl) avermectin A 1a) and its delta - 8,9 - isomer) Plants: sum of avermectin B1a, avermectin B1b, 8,9 - Z - av ermectin B1a an d 8,9 - Z avermectin B1b. Animal commodities: sum of avermectin B1a and 8, 9 - Z avermectin B1a. Commodity Tolerance (ppm) /Maximum Residue Limit (mg/kg) US Canada Mexico Codex Onion, bulb, subgroup 3 - 07A 0.01 Chive, fresh leaves 0.01 Chive, dried leaves 0.02 Bean, dry, seed , except cowpea 0.01

Completed: M. Negussie; 03/31/2011