L-Glutamic Acid (LGA) and Gamma-Aminobutyric Acid (GABA) EPA-HQ-OPP-20 14-0 I 09 

www.regulations.gov 

L-Glutamic Acid (LGA) and Gamma-Aminobutyric Acid 

(GABA) 

(PC Codes: 374350 and 030803) 

Final Work Plan 

Registration Review 

Case Number 6025 

March 2015 

Approved by: 

Biopesticides and 

Pollution Prevention Division 

Date: 
INTRODUCTION 

This is the Environmental Protection Agency's (EPA or the Agency) Final Work Plan (FWP) for 

the registration review of L-glutamic acid (LGA) and gamma-aminobutyric acid (GABA). This 

work plan addresses updates, additional data needs, and public comments received concerning 

the Preliminary Work Plan (PWP), which was posted in the L-glutamic acid (LGA) and garnmaaminobutyric acid (GABA) registration review docket (EPA-HQ-OPP-2014-0109) on September 

24, 2014. Two products containing LGA and GABA are currently registered for use as plant 

growth regulators. 

The Agency is implementing the registration review program pursuant to Section 3(g) of the 

Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and will review each registered 

pesticide every 15 years to determine whether it continues to meet the FIFRA standard for 

registration. Changes in science, public policy, and pesticide use practices occur over time. The 

registration review program is intended to make sure that, as the ability to assess risk evolves and 

as policies and practices change, all registered pesticides continue to meet the statutory standard. 

The public phase of registration review begins when the initial docket is opened for each case. 

Information on this program is provided on the Agency's website. 1 

The FWP begins with any updates since the PWP was issued. Next is a summary of substantive 

comments received during the public comment period for the PWP concerning anticipated data 

needs, expected risk assessments, or the estimated timeline identified in the PWP, and a 

summary of the Agency's responses to those comments. This section is followed by registration 

review planned data needs, risk assessments expected to be conducted, and the projected 

registration review timeline for LGA and GABA. Lastly, there is a discussion of next steps. 

UPDATES SINCE THE PWP WAS ISSUED 

Since the PWP for LGA and GABA was issued, CP Bio GABA Technical was registered on 

December 17, 2014, containing its active ingredient, Gamma-aminobutyric acid (GABA), at 

99%. The product is intended for formulation into end-use-products (EPs) to be used as plant 

growth regulators (PGRs) to increase yields in growing crops, turf, and agricultural and 

ornamental trees. 

SUMMARY OF COMMENTS AND AGENCY RESPONSES 

During the 60-day public comment period on the LGA and GABA PWP, which opened on 

September 24, 2014, and closed on November 24, 2014, the Agency received one (1) comment 

concerning this case.2 The comment was submitted by the Center for Biological Diversity. The 

comment stated that EPA must consult with U.S. Fish and Wildlife Service and the National 

Marine Fisheries under Section 7 of the Endangered Species Act to insure that LGA and GABA 

do not jeopardize the continued existence of any listed species or result in adverse modification 

or destruction of critical habitat. 

1

http://www2.epa.gov/pesticide-reevaluation/ 2 Federal Register, Volume 79, Issue No. 185 pp. 57092 - 57095 (issued Wed. September 24, 2014). 

2 
Summarized below is the public comment and the Agency's response. The public comment is 

available in the entirety in the docket, EPA-HQ-OPP-2014-0109. 

Comment submitted by Center for Biological Diversity in EPA-HQ- OPP-2014-0109. 

1. Comment: a). "EPA has an independent duty under the Endangered Species Act to Consult 

with the US. Fish and Wildlife Service and National Marine Fisheries on the Reregistration of 

LGA and GABA. b). The EPA must make a defensible "Not Likely to Adversely Affect" and 

"Likely to Adversely Affect" Determination as a Prerequisite for Defensible "Jeopardy" and 

"No Jeopardy" Determinations. c). EPA and the Services must assess the Adverse impacts of 

LGA and GABA in Critical Habitat. d). EPA has an independent Duty under the Endangered 

Species Act to Consult with the US. Fish and Wildlife Service and National Marine Fisheries 

Service on the Approval of All LGA and GABA end-use product labels. " 

Response: 

As indicated in the PWP, the Agency concluded that the risks to nontarget species, including 

federally listed threatened or endangered species (listed species) and/or their designated 

critical habitat, from the use of LGA and GABA as PGRs are negligible, and will have "no 

effect" on listed species and/or their designated critical habitat, based upon the low toxicity of 

LGA and GABA demonstrated in the mammalian acute toxicity studies (U.S. EPA 2014) and 

the nontarget freshwater invertebrate and fish studies, their ubiquity in living organisms, and 

the low application rates as PGRs. EPA anticipates conducting no further analysis of potential 

risks to endangered or threatened species, unless data or information are obtained during the 

registration review process that would indicate such an assessment would be needed to inform 

the Agency's decision. 

T he data requirements for nontarget birds (avian acute oral and dietary toxicity studies), 

plants, and insects were waived, based upon the low acute toxicity of LGA and GABA in 

mammalian species, their natural occurrence, their biodegradability in the environment3and the 

presence of these substances in virtually all living plants and animals, including humans. From 

the submitted studies, the 96 hour LCso in freshwater fish (species tested was the rainbow trout, 

Oncorhynchus mykiss) and the 48 hour ECso value for the freshwater invertebrate, Daphnia 

magna, are > 100 mg/L. The No Observed Effect Concentration (NOEC) value was 

determined to be 100 mg/L, based upon no mortality at the highest concentration tested in 

these studies, which classifies LGA and GABA as practically nontoxic to these organisms 

(U.S. EPA, 2014). 

PLANNED DATA NEEDS 

The PWP stated that there were no anticipated data needs for the LOA and GABA registration 

review. That has not changed. 

3 Half-life in water = 8.7 days; in soil = 17.3 days- Level III Fugacity Model, generated using USEPA's 

"EP!SuiteTM" http://www .chemspider.com/Chemicai-Structure.ll6.html 

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RISK ASSESSMENTS FOR REGISTRATION REVIEW 

Since publication of the PWP, the agency has completed a comprehensive risk assessment (U.S. 

EPA, 2014) for GABA, in support of a new manufacturing- use-product (MP) registration, CP 

Bio GABA Technical. The agency has concluded that there are no data gaps for LGA or GABA 

and that there is no need to conduct a new risk assessment for these active ingredients during 

registration review. 

TIMELINE 

EPA has created the following estimated timeline for the completion of the LGA and GABA 

registration review in Table 1, below. This projected timeline has not changed since the PWP. 

Registration Review for LGA and GABA- Projected Registration Review Timeline 

Activities Estimated Month/Year 

Op_ening the Docket 

Open Docket and 60-Day Public Comment Period for LGA and GABA September 2014 

Close Public Comment Period November 2014 

Case Development 

Issue Final Work Plan March 2015 

Issue Data Call-in N/A 

Data Submission NIA 

Open 30-Day Public Comment Period for Draft Risk Assessments NIA 

Close Public Comment Period NIA 

Registration Review Decision 

Open 60-Day Public Comment Period for Proposed Registration Review December 2015 

Decision 

Close Public Comment Period February 2016 

Final Decision June 2016 

*Estimated Total (years) 1 year and 9 months 

* This schedule is subject to rev1sion should unforeseen 1ssues anse dunng the reg1strat1on rev1ew process. In the 

event an issue arises, such as the failure to acquire an EDSP exemption, an amended Final Work Plan will be 

issued at that time. That Final Work Plan will identify newly anticipated data needs (if any) and set forth a new 

timeline. 

NEXT STEPS 

The Agency plans to issue a Proposed Registration Review Decision for this case in December 

2015. At that time, a 60-day public comment period will be opened for the Proposed Decision. 

4 
U.S. Environmental Protection Agency Risk Assessment Memoranda 

U.S. EPA. 1997. Registration of AuxiGro (EPA File Symbol 70810-R) and Exemption from the 

requirement of a tolerance for GABA (pp#7F4843) and L-Glutamic Acid (PP#7F4842) on all 

RAW Agricultural Commodities (RACs). Review of Product Chemistry, Mammalian Toxicology 

and Eco-Toxicity Studies. (Chemical Nos. 030802 and 374350); MRID Nos. 442962-01 to 07, 

442964-01 to 21; and 442962-01 to 442962-06). Memorandum from Freshteh Toghrol to Edward 

Allen. U.S. Environmental Protection Agency (U.S. EPA). October 06, 1997. 

U.S. EPA. 1998. Review of Freshwater Acute Toxicity Studies, Chemical No. 030.802, 374350; 

MRID Nos. 444057-01 and 02. Memorandum from Edward Allen to Freshteh Toghrol. U.S. 

Environmental Protection Agency (U.S. EPA). April 13, 1998 

U.S. EPA. 1998. GABA and L-Glutamic Acid (030802, 374350) Technical Document. U.S. 

Environmental Protection Agency (U.S. EPA). Issued September, 1998. Available at: 

http://www.epa.gov/oppOOOO 1/chem search/reg actions/registration/related PC-030802 1-Sep98.pdf 

U.S. EPA. 2004. GABAand L-GlutamicAcid (030802, 374350) Fact Sheet. Issued October 19, 

2004. Available at: http://www.epa.gov/oppOOOOllchem search/reg actions/registrationlfs G132 19-0ct-04.pdf 

U.S. EPA. 2014. L-Glutamic Acid (LOA) and Gamma-Aminobutyric Acid (GABA) (PC Codes: 

374350 and 030803). Preliminary Work Plan and Summary Document. U.S. Environmental 

Protection 

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