


EPA REGISTRATION DIVISION COMPANY NOTICE OF FILING FOR PESTICIDE PETITIONS PUBLISHED IN THE FEDERAL REGISTER  

EPA Registration Division contact: [PV Shah, (703) 308-1846]

INSTRUCTIONS:  Please utilize this outline in preparing the pesticide petition.  In cases where the outline element does not apply, please insert "NA-Remove" and maintain the outline. Please do not change the margins, font, or format in your pesticide petition. Simply replace the instructions that appear in green, i.e., "[insert company name]," with the information specific to your action.

TEMPLATE:

[Rhodia Inc.]

[2E8010]

	EPA has received a pesticide petition ([2E8010]) from [Rhodia Inc., c/o SciReg, Inc.], [12733 Director's Loop, Woodbridge, VA 22192] proposing, pursuant to section 408(d) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a(d), to amend 40 CFR part 180.910 to establish an exemption from the requirement of a tolerance for 	[methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (CAS No. 1174627-68-9) and related reaction products, herein referred to as methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate, under 40 CFR 180.910 when used as an inert ingredient in pesticide formulations.] EPA has determined that the petition contains data or information regarding the elements set forth in section 408 (d)(2) of  FDDCA; however, EPA has not fully evaluated the sufficiency of the submitted data at this time or whether the data supports granting of the petition. Additional data may be needed before EPA rules on the petition.

A. Residue Chemistry

	1. Plant metabolism.

	2. Analytical method. [Rhodia is requesting that methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate be exempt from the requirement of a tolerance under 40 CFR 180.910. Therefore, Rhodia believes that an analytical method to determine residues in treated crops is not relevant.]

	3. Magnitude of residues. [Rhodia is requesting that methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate be exempt from the requirement of a tolerance under 40 CFR 180.910. Therefore, Rhodia believes that data on the magnitude of residues in treated crops is not relevant.]

B. Toxicological Profile

	1. Acute toxicity.  [Acute Oral Toxicity

The acute oral toxicity of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was assessed in the rat in accordance with OECD Guideline No. 423 (2001) and U.S. EPA Guideline OPPTS 870.1100. The study was performed in compliance with the Principles of Good Laboratory Practice Regulations [Hungarian GLP Regulations: 9/2001.(III.30.) EüM-FVM joint decree of the Minister of Health and the Minister of Agriculture and Regional Development] which corresponds to the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

Two groups each of three female (W1) BR Wistar rats were treated with methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate by oral gavage administration at a dose of 2,000 mg/kg body weight. The test item was administered undiluted at a dose volume of 1.92 mL/kg. The animals were examined daily during the acclimatization period and mortality, viability and clinical signs were recorded. All animals were examined for clinical signs and mortality within the first 30 minutes and at approximately 1, 2, 3, 4 and 6 hours after treatment on Day 1 and once daily during test Days 2-15. Body weights were recorded on Day -1, Day 0 (prior to administration) and on Days 7 and 14. All animals were necropsied and examined macroscopically. 

All animals survived until the end of the study period. No clinical signs were observed during the course of the study. The body weight of the animals was within the range commonly recorded for rats of this strain and age. No macroscopic findings were recorded at necropsy. The median lethal dose LD50 (female rat) of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate after single oral administration was found to be greater than 2,000 mg/kg body weight.  

Acute Dermal Toxicity

The acute dermal toxicity of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was assessed in the rat in accordance with OECD Guideline No. 402 (1987). The study was performed in compliance with UK GLP standards [Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994] which are in accordance with the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

A group of ten Wistar (RccHan:WIST) rats (five males and five females) were given a single, 24 hour, semi-occluded dermal application of the undiluted test item to intact skin at a dose of 2,000 mg/kg body weight. Clinical signs and body weight development were monitored during the study. All animals were subjected to a gross necropsy. 

There were no deaths. Red/brown staining around the snout was noted in two males during the day of dosing. There were no other signs of systemic toxicity noted. There were no signs of dermal irritation. Animals showed expected gains in body weight over the study period except for one female which showed bodyweight loss during the first week but expected gain in body weight during the second week. No abnormalities were noted at necropsy. The acute dermal median lethal dose (LD50) of the test item in the Wistar strain rat was found to be greater than 2,000 mg/kg body weight.  

Primary Eye Irritation

The acute ocular irritation potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was assessed in the rabbit in accordance with OECD Guideline No. 405 (2002) and U.S. EPA Guideline OPPTS 870.2400. The study was performed in compliance with the Principles of Good Laboratory Practice Regulations [Hungarian GLP Regulations 9/2001.(III.30.) EüM-FVM joint decree of the Minister of Health and the Minister of Agriculture and Regional Development] which corresponds to the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

The test item was placed into the conjunctival sac of the left eye of each of three New Zealand White rabbits. The untreated right eye served as control. A volume of 0.1 mL of the test item was administered as a single dose. The eyes were examined at 1, 24, 48, amd 72 hours and 1 and 2 weeks after application of the test item.

Instillation of the test solution produced evidence of irritant effects in the eyes of all three rabbits. An Initial Pain Reaction (IPR) (score 2) was observed in all animals. 
One hour after the application, conjunctival redness (score 2) was observed in all animals, conjunctival chemosis (score 3) was noted in all animals, conjunctival 
discharge (score 3) was seen in all animals and corneal opacity (score 1, area 4) was observed in two animals. Effects were still observed at 24, 48, and 72 hours in all the 
animals with individual mean scores at 24, 48, and 72 hours after treatment as 
follows: 0.67, 0.33, 0.00 for iritis; 3.00, 2.67, 1.67 for conjunctival redness; 0.33, 1.33, 
0.67 for conjunctival chemosis; and 1.00, 1.00, 1.00 for corneal opacity.

At one week after treatment, conjunctival redness (score 1) was still present in two animals and corneal opacity (score 1, area 2) was observed in one rabbit. At two weeks after treatment, no clinical signs were observed, irritation was considered to be fully reversible within this period and the study was terminated. During the study, the control eye of each animal was symptom-free. The general state and behavior of animals were normal throughout the study period. There were no notable body weight changes during the study period. Based on the reported scores, the maximum mean total score (MMTS) can be calculated as 34/110 at 24-hours. The test substance is considered a moderate ocular irritant (modified Kay and Calandra interpretation of eye irritation). 

Primary Dermal Irritation

The acute skin irritation potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was assessed in the rabbit in accordance with OECD Guideline No. 404 (2002) and U.S. EPA Guideline OPPTS 870.2500. The study was performed in compliance with the Principles of Good Laboratory Practice Regulations [Hungarian GLP Regulations 9/2001.(III.30.) EüM-FVM joint decree of the Minister of Health and the Minister of Agriculture and Regional Development] which corresponds to the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

The test item was administered undiluted at a single dose of 0.5 mL to three New Zealand White rabbits. Gauze was placed onto the clipped skin of each rabbit, test item was applied to the gauze, additional gauze was placed over the test item and an adhesive clear plastic patch applied. The trunk was wrapped in clear plastic with medical tubing used to hold the patch in place. The untreated skin of each animal served as control. After four hours, the remaining test item was removed with water at body temperature. To assess skin irritation, animals were examined at 1, 24, 48 and 72 hours after patch removal. Additional general examinations were performed daily.

There was no mortality and no systemic clinical changes were observed throughout the study. There was no effect of treatment on body weight. No clinical signs were noted on the skin of the treated animals at the 1, 24, 48 and 72 hours observations after patch removal (readings were 0 for both erythema and edema formation). As no clinical signs were observed up to 72 hours after patch removal, the study was terminated after the 72 hour observation. Based on these results, the test substance methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is not considered a skin irritant.




Dermal Sensitization

The contact allergenic potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was assessed in the mouse in a local lymph node assay in accordance with OECD Guideline No. 429 (2002). The study was performed in compliance with the Principles of Good Laboratory Practice Regulations [Hungarian GLP Regulations 9/2001.(III.30.) EüM-FVM joint decree of the Minister of Health and the Minister of Agriculture and Regional Development] which corresponds to the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

Based on the results of the preliminary compatibility test, the test item was dissolved in an acetone:olive oil 4:1 mixture (AOO). The maximum attainable concentration was 50%. The Preliminary Irritation/Toxicity Test was performed in CBA/J@Rj mice using two doses [test item concentrations of 50 and 25 (w/v) %] in the selected vehicle. The applicability and biocompatibility of the test item on the ears of animals at the maximum concentration of test item of 50% was acceptable. In the main assay, 20 female CBA/J@Rj mice were allocated to five groups of four animals each. Three groups received the appropriate formulation of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate at concentrations of 50%, 25% and 10%, the negative control group received AOO and the positive control group received 25 (w/v) % α-Hexylcinnamaldehyde (HCA) in AOO. The test item solutions were applied on the dorsal surface of ears of experimental animals (25 μl/ear) for three consecutive days (Days 1, 2 and 3). There was no treatment on Days 4, 5 and 6. On Day 6, the cell proliferation in the local lymph nodes was measured by incorporation of tritiated methyl thymidine (3HTdR) and the values obtained were used to calculate stimulation indices (SI).

The animals did not show any clinical signs during the course of the study and no cases of mortality were observed. No local signs of irritation of the ear skin were detected. Stimulation Indices (S.I.) of 1.7, 1.6 and 1.2 were determined with the test item at concentrations of 10, 25 and 50% in AOO, respectively. The validity of the assay was demonstrated from the positive control substance HCA25% in AOO, with S.I. of 9.4. 

Based on the results of this study, the test substance methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is not considered a skin sensitizer.]

	2. Genotoxicty. [Bacterial Reverse Mutation Test

The potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate to induce gene mutations in bacteria was assessed in accordance with OECD Guideline No. 471 (1997) and U.S. EPA Guideline OPPTS 870.5100. The study was performed in compliance with the Principles of Good Laboratory Practice Regulations [Hungarian GLP Regulations 9/2001.(III.30.) EüM-FVM joint decree of the Minister of Health and the Minister of Agriculture and Regional Development] which corresponds to the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

The assay was performed using Salmonella typhimurium strains TA98, TA100, TA1535, and TA1537, and Escherichia coli strain WP2 uvrA in two independent experiments in the plate incorporation test (experiment I) and the pre-incubation test (experiment II), both with and without liver microsomal activation at concentrations from 5 to 5,000 ug/plate. Each concentration, including the controls, was tested in triplicate.

The plates incubated with the test item showed normal background growth up to 5,000 ug/plate with and without metabolic activation in both independent experiments. No toxic effects, evident as a reduction in the number of revertants (below the induction factor of 0.5), occurred in the test groups with or without metabolic activation. No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate at any dose level, either in the presence or absence of metabolic activation (S9 mix). There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. Appropriate reference mutagens were used as positive controls and showed a distinct increase of induced revertant colonies. 

Under the experimental conditions of this study, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used. 
Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is therefore considered to be non-mutagenic in this Salmonella typhimurium and Escherichia coli reverse mutation assay.

In Vitro Mammalian Cell Gene Mutation Test

The potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster in vitro was assessed in accordance with OECD Guideline No. 476 (1998). The study was performed in compliance with the OECD Principles of Good Laboratory Practice as revised in 1997 [C(97)186/Final].

The assay was performed in two independent experiments. The cells were exposed to the test item for four hours in the first experiment with and without metabolic activation. The second experiment was performed with a treatment time of four hours with and 24 hours without metabolic activation. The highest concentration of the test item was equal to a molar concentration of about 10 mM. The tested concentrations were from 17.3 to 2,220 ug/mL.

No substantial and reproducible dose dependent increase of the mutation frequency was observed in either main experiment. Appropriate reference mutagens, used as 
positive controls, induced a distinct increase in mutant colonies and, thus showed 
the sensitivity of the test system and the activity of the metabolic activation system. 

Under the experimental conditions reported, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate did not induce gene mutations at the HPRT locus in V79 cells.

In Vitro Mammalian Chromosome Aberration Test

The potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate to induce structural chromosomal aberrations in human lymphocytes in vitro was assessed in accordance with OECD Guideline No. 473 (1997). The study was performed in compliance with the OECD Principles of Good Laboratory Practice as revised in 1997 [C(97)186/Final].

The test item, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate, dissolved in deionized water, was examined in two independent experiments. In each experimental group, two parallel cultures were analyzed. Per culture, 100 metaphases were scored for structural chromosomal aberrations. The highest applied concentration in this study (2,220 ug/mL of the test item, approximately 10 mM) was chosen with regard to the molecular weight and the purity of the test item and with respect to the current OECD Guideline. Dose selection of the cytogenetic experiment was performed considering the toxicity data. The treatment concentrations were from 14.4 to 2,220 ug/mL.

In the absence and presence of S9 mix, no cytotoxicity was observed up to the highest applied concentration. In both independent experiments, neither a statistically significant nor a biologically relevant increase in the number of cells carrying structural chromosomal aberrations was observed after treatment with the test item. No evidence of an increase in polyploid metaphases was noticed after treatment with the test item as compared to the control cultures. Appropriate mutagens were used as positive controls. These induced statistically significant increases (p < 0.05) in cells with structural chromosome aberrations.

Under the experimental conditions reported, the test item did not induce structural chromosomal aberrations in human lymphocytes in vitro. Therefore, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is considered to be non-clastogenic in this chromosome aberration test, when tested up to the highest required concentration.

In vivo Mammalian Erythrocyte Micronucleus Test

The potential of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate to produce damage to chromosomes or aneuploidy was investigated according to OECD Guideline 474 (1997). The study was performed in compliance with UK GLP standards [Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994] which are in accordance with the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

The micronucleus test was conducted using the intraperitoneal route in groups of seven mice (males) at the maximum tolerated dose (MTD) of 2,000 mg/kg and with 1,000 and 500 mg/kg as the two lower dose levels. Animals were killed 24 or 48 hours later, the bone marrow extracted, and smear preparations made and stained. Polychromatic (PCE) and normochromatic (NCE) erythrocytes were scored for the presence of micronuclei. Additional groups of mice were given a single intraperitoneal dose of distilled water (seven male mice) or dosed orally with cyclophosphamide (five male mice), to serve as vehicle and positive controls, respectively. Vehicle and positive control animals were killed after 24 hours.

There were no premature deaths seen in any of the dose groups in the main test. Clinical signs consisting of hunched posture, ptosis and ataxia were observed in animals dosed with the test item at and above 1,000 mg/kg in both the 24 and 48-hour dose groups Animals dosed at 2,000 mg/kg in both the 24 and 48-hour dose groups exhibited decreased respiratory rate, labored respiration and loss of righting reflex up to 10 minutes after dosing. The observation of the clinical signs was taken to indicate that systemic absorption had occurred and exposure to the target tissue had been achieved. No statistically significant decreases in the PCE/NCE ratio were observed in any of the test item dose groups when compared to the vehicle control group. There were no statistically significant increases in the frequency of micronucleated PCE in any test item dose groups. The positive control group showed a marked increase in the incidence of micronucleated polychromatic erythrocytes hence confirming the sensitivity of the system to the known mutagenic activity of cyclophosphamide under the conditions of the test. 

Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was considered to be non-genotoxic under the conditions of the test.]

	3. Reproductive and developmental toxicity. [Combined Repeat Dose Toxicity with Reproduction/Developmental Toxicity Screening Test 

The systemic toxicity and potential adverse effects of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate on reproduction including offspring development was investigated in accordance with OECD  Guideline 422 (1996). The study was performed in compliance with UK GLP standards [Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994] which are in accordance with the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

The test item was administered by oral gavage to three groups, each of ten male and ten female Wistar Han(TM):RccHan(TM):WIST strain rats, for up to eight weeks (including a two week maturation phase, pairing, gestation and early lactation for females), at dose levels of 30, 300 and 1,000 mg/kg bw/day. A control group of ten males and ten females was dosed with vehicle alone (distilled water). Clinical signs, behavioral assessments, body weight change, food and water consumption were monitored during the study. Pairing of animals within each dose group was undertaken on a one male:one female basis within each treatment group on Day 15 of the study, with females subsequently being allowed to litter and rear their offspring to Day 5 of lactation. During the lactation phase, daily clinical observations were performed on all surviving offspring, together with litter size and offspring weights and assessment of surface righting reflex. Extensive functional observations were performed on five selected males from each dose group after the completion of the mating phase, and for five selected parental females from each dose group on Day 4 post partum. Hematology and blood chemistry were evaluated prior to termination on five selected males and females from each dose group. Adult males were terminated on Day 43, followed by the termination of all females and offspring on Day 5 post partum. All animals were subjected to a gross necropsy examination and histopathological evaluation of selected tissues was performed.

There were no deaths during the study. Clinical findings were confined to transient episodes of increased salivation in one 300 mg/kg bw/day male on Day 17 and among animals of either sex at 1,000 mg/kg bw/day between Days 30 and 46. There were no treatment-related changes in the behavioral parameters measured, functional performance or sensory reactivity. Weight development in all test animals was comparable to that of the controls throughout the treatment period. No adverse effects on food consumption, food efficiency or water consumption were detected in test animals in comparison with controls.

There was no evidence of treatment-related changes in the hematological parameters measured and no convincing treatment-related adverse effects identified for the biochemistry profile. There were no macroscopic abnormalities detected. An increase (p < 0.01) in absolute and relative liver weight was identified in 1,000 mg/kg bw/day males. Females at this dose level showed an increase (p < 0.05) in absolute and relative kidney weight in comparison with controls. Individual values all fell within the historical ranges for rats of the age and strain used. Treatment related microscopic findings were confined to minimal to slight centrilobular hepatocyte hypertrophy in four out of five males receiving 1,000 mg/kg bw/day. None of these changes were considered to be toxicologically significant, therefore the NOAEL for systemic toxicity was considered to be 1,000 mg/kg bw/day. No treatment-related systemic toxicity was detected in either sex at 30 and 300 mg/kg bw/day, therefore the NOEL for systemic toxicity was considered to be 300 mg/kg bw/day.

There were no treatment-related effects on mating, conception rate or gestational length in animals of either sex treated with 30, 300 or 1,000 mg/kg bw/day. Of the litters born, litter size at birth and subsequently on Day 1 and Day 4 post partum, as well as, offspring body weight gain and litter weights were comparable to controls. No adverse effects were detected in surface righting reflex on Day 1. No effect on the reproductive organs of parental animals was detected during post mortem or histopathological assessments. There was no evidence of any developmental effects observed in offspring from treated litters. The NOEL for reproductive toxicity was therefore considered to be 1,000 mg/kg bw/day.]

	4. Subchronic toxicity. [Combined Repeat Dose Toxicity with Reproduction/Developmental Toxicity Screening Test 

The systemic toxicity and potential adverse effects of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate on reproduction including offspring development was investigated in accordance with OECD Guideline 422 (1996). The study was performed in compliance with UK GLP standards [Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994] which are in accordance with the OECD Principles of Good Laboratory Practice [ENV/MC/CHEM(98)17].

The test item was administered by oral gavage to three groups, each of ten male and ten female Wistar Han(TM):RccHan(TM):WIST strain rats, for up to eight weeks (including a two week maturation phase, pairing, gestation and early lactation for females), at dose levels of 30, 300 and 1,000 mg/kg bw/day. A control group of ten males and ten females was dosed with vehicle alone (distilled water). Clinical signs, behavioral assessments, body weight change, food and water consumption were monitored during the study. Pairing of animals within each dose group was undertaken on a one male:one female basis within each treatment group on Day 15 of the study, with females subsequently being allowed to litter and rear their offspring to Day 5 of lactation. During the lactation phase, daily clinical observations were performed on all surviving offspring, together with litter size and offspring weights and assessment of surface righting reflex. Extensive functional observations were performed on five selected males from each dose group after the completion of the mating phase, and for five selected parental females from each dose group on Day 4 post partum. Hematology and blood chemistry were evaluated prior to termination on five selected males and females from each dose group. Adult males were terminated on Day 43, followed by the termination of all females and offspring on Day 5 post partum. All animals were subjected to a gross necropsy examination and histopathological evaluation of selected tissues was performed.

There were no deaths during the study. Clinical findings were confined to transient episodes of increased salivation in one 300 mg/kg bw/day male on Day 17 and among animals of either sex at 1,000 mg/kg bw/day between Days 30 and 46. There were no treatment-related changes in the behavioral parameters measured, functional performance or sensory reactivity. Weight development in all test animals was comparable to that of the controls throughout the treatment period. No adverse effects on food consumption, food efficiency or water consumption were detected in test animals in comparison with controls.

There was no evidence of treatment-related changes in the hematological parameters measured and no convincing treatment-related adverse effects identified for the biochemistry profile. There were no macroscopic abnormalities detected. An increase (p < 0.01) in absolute and relative liver weight was identified in 1,000 mg/kg bw/day males. Females at this dose level showed an increase (p < 0.05) in absolute and relative kidney weight in comparison with controls. Individual values all fell within the historical ranges for rats of the age and strain used. Treatment related microscopic findings were confined to minimal to slight centrilobular hepatocyte hypertrophy in four out of five males receiving 1,000 mg/kg bw/day. None of these changes were considered to be toxicologically significant, therefore the NOAEL for systemic toxicity was considered to be 1,000 mg/kg bw/day. No treatment-related systemic toxicity was detected in either sex at 30 and 300 mg/kg bw/day, therefore the NOEL for systemic toxicity was considered to be 300 mg/kg bw/day.

There were no treatment-related effects on mating, conception rate or gestational length in animals of either sex treated with 30, 300 or 1,000 mg/kg bw/day. Of the litters born, litter size at birth and subsequently on Day 1 and Day 4 post partum, as well as, offspring body weight gain and litter weights were comparable to controls. No adverse effects were detected in surface righting reflex on Day 1. No effect on the reproductive organs of parental animals was detected during post mortem or histopathological assessments. There was no evidence of any developmental effects observed in offspring from treated litters. The NOEL for reproductive toxicity was therefore considered to be 1,000 mg/kg bw/day.]

	5. Chronic toxicity. [No experimental carcinogenicity study is available on methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate. Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was assessed using the knowledge-based expert system DEREK for Windows (software version DfW 9.0.0,14_08_2006). The expert system DEREK has been designed for the qualitative prediction of the possible toxicity of chemicals and the following endpoints were searched for this structure: carcinogenicity, genotoxicity, HERG channel inhibition, irritation, respiratory sensitization, skin sensitization, thyroid toxicity, and miscellaneous endpoints. The toxicity assessments are based on the presence of specific substructures. The ester amide structure of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate triggered the alert "irritation of the gastrointestinal tract", with a level of likelihood "Plausible" [Structural alert 048: alpha-substituted propionic acid or ester; rules 47 and 243]. This prediction is associated with the methyl group being close to an ester link such that substituted propionic acid could be created, triggering an alert for gastrointestinal irritation based on the side effects documented in the knowledge database with propionic acid-based nonsteroidal anti-inflammatory drugs (NSAIDs) following administration by the oral and parenteral routes. Their irritancy is reported to be predominantly a consequence of physico-chemical disruption of the gastric intestinal mucosa. As an automatic consequence of triggering the structural alert for gastrointestinal irritation, the super-endpoint of carcinogenicity was also triggered with the same likelihood (Rule 704). 

In DEREK, the endpoint carcinogenicity can be triggered due to extrapolation from certain other endpoint alerts as opposed to specific, recognized, carcinogenic 
toxicophores. It is well-recognized in the scientific literature that gastrointestinal irritation is not necessarily relevant to predict cancer risk in humans. No other alerts were triggered. The other minor structures present as impurities in the substance (including the impurities methyl 4-(dimethylamino)-ethyl-4-oxobutanoate, and N1,N1,N5,N5,2-pentamethylpentanediamide) did not trigger any alert in the DEREK model.

In the absence of significant findings in the gastrointestinal tract during macroscopic and histopathology examination in rats treated by oral gavage for up to eight weeks, and considering the absence of genotoxic effects in the available in vitro and in vivo studies, the alert in the DEREK model is not considered predictive of a particular toxicological concern or carcinogenicity potential that would be relevant to the use conditions foreseen.]

	6. Animal metabolism. [NA-Remove.]

	7. Metabolite toxicology. [NA-Remove.]

	8. Endocrine disruption. [There is no available evidence demonstrating that methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is an endocrine disruptor in humans.]

C. Aggregate Exposure

	1. Dietary exposure. [In examining aggregate exposure, section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA) directs EPA to consider available information concerning exposures from the pesticide residue in food and all other nonoccupational exposures, including drinking water from ground water or surface water and exposure through pesticide use in gardens, lawns, or buildings (residential and other indoor uses).

It is anticipated that methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate will be used as a solvent in EC formulations at a concentration no higher than 30%. Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is not expected to be persistent in the environment based on a PBT assessment of the substance. Further, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate has a low toxicity profile as demonstrated through acute, subchronic, developmental, and mutagenicity testing. Therefore, dietary exposure to methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate should not be of concern.

Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate will not be applied directly to water. Agricultural practices minimize spray drift and typical end-use product labels prohibit direct application to water. Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is inherently biodegradable and is not expected to be persistent in the environment. Therefore, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate as a solvent in EC formulations does not pose a risk to drinking water.


Overall, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is considered to be a low toxicity substance with a reasonable certainty of no harm from dietary exposure and all other nonoccupational sources of exposure.]

	i. Food. [NA-Remove.]

	ii. Drinking water. [NA-Remove.]

	2. Non-dietary exposure. [NA-Remove.]

D. Cumulative Effects

	[Section 408(b)(2)(D)(v) of the FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider "available information" concerning the cumulative effects of the particular pesticide's residues and "other substances that have a common mechanism of toxicity."

Rhodia has not found methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate to share a common mechanism of toxicity with any other substances, and methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate does not appear to produce a toxic metabolite produced by other substances. 

Resultant risks, separately and/or combined with other substances that may have a common mechanism of toxicity, should be low for methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate. Rhodia does not expect any adverse cumulative effects associated with the use of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate.]

E. Safety Determination

	1. U.S. population. [Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate exhibits a low toxicity profile, as demonstrated by the acute, subchronic, carcinogenicity, reproductive, and developmental studies summarized above. Further, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate was not mutagenic in in vitro and in vivo studies. When methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate is used on raw agricultural commodities in accordance with good agricultural practice, it is expected to meet the reasonable certainty of no harm requirement. Based on the low toxicity profile of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate, there is no reason to believe that adverse effects on the U.S. population will result from the use of this inert ingredient in pesticide formulations. In addition, there is no reason to believe that infants and children will be disproportionately at risk to the use of methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate in pesticide formulations.]

	2. Infants and children. [NA-Remove.]

F. International Tolerances

	[There are no known U.S. or international tolerances or tolerance exemptions for methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate.]




