Proposed Registration Decision for the New Active 

Ingredient Choline Chloride 

l : 

Ja E. ci senge ~ Director 

0 fice of' Pesticide 'Programs 

Date: //- 13 -1 S 
Summa ry 

This document announces that the Environmental Protection Agency (EPA) has completed its 

initial eval uation of the proposed new plant growth regulator (PGR) Choline Chloride and has 

concluded that it meets the regulatory and safety standards under the Federal Insecticide. 

Fungicide and Rodenticide Act (FIFRA). 

Two products are proposed to be registered under ection 3(c)(5) ofTIFRA: a Manufacturinguse Product (M P), Choline Chloride Technical; and an End-use Product (EP). Choline Chloride 

SP 20%. The EP is intended for foliar application to growing crops, including food crops, and is 

Lo be supported by an exemption from the requirement or a tolerance. allowing for the use of 

Choline Chloride "in or on all food commodities when applied/used preharvest and used in 

accordance with label directions and good agricultural practices". 

Choline Chloride is a quaternary ammonium salt consisting or a choline cation with a chloride 

anion. /\s with many salts, it presents as a white crystalline solid that is odorless. It readily 

dissociates into two constituents - Choline and Chloride - particularly in water. Each constituent 

is ubiquitous in the environment, constitutes a regular part or the human diet, and serves many 

criti cal functions in the human body. Choline is found in vegetables, animal fat and egg yolks; it 

is a precursor for the production of the neurotransmitter acetylcholine. is important for the 

structural integrity of cell membranes and is important in multiple physiological pathways such 

as methylation metabolism. transmembrane signaling and lipid and cholesterol transport and 

metabolism. Chloride is a major constituent of edible salt; it is an essential electrolyte located in 

all body fluids and is responsible for maintaining acid/base balance. transmitting nerve impulses 

and regulating fluid in and out of cells. 

As a biopesticide. Choline Chloride is classified as a plant growth regul ator (PGR). FIFRA Sec 2 

( 136) (v) establishes the definition of plant regulators and carves out terms of exclusion: "The 

term "plant regulator .. means any substance or mix lure of substances intended, through 

physiological action. for accelerating or retarding the rate of growth or rate of maturation or for 

otherwise altering the behavior of plants thereof, but shall not include substances to the extent 

that they arc intended as plant nutrients, trace elements, nutritional chemicals, plant inoculants, 

and soil amendments." In making its determination that Choline Chloride is a biopesticide, the 

/\gency, based on in formation reviewed, concluded that the proposed use of Choline Chloride 

docs not meet the terms of exclusion and requires registration because its direct application to 

plants changes the behavior (physiology) of the plant. and because it is intended for use on food 

crops. ' pecificall y. the Choline Chloride EP is to be applied as a foliar spray directly to the 

foliage of growing plants at application rates ranging from 0.0004 to 0.282 lb ai/A with a 

maximum of 4 applications per season. Its application is intended to increase plant growth and 

decrease stress in growing crops. The crops listed on the labeling for this new acti ve ingredient 

include fruiting vegetables. cereal grains. stone fruit. tree nuts and cotton. The most active 

constituent or the active ingredient is considered to be Choline but the Chloride Salt of Choline 

compound (Choline Chloride) provides joint acti vity as the salt compound is more stable and 

effective as a de li very vehicle. As with most PG Rs. Choline Chloride is necessarily appl ied at 

low concentrations because use at high concentrations results in detrimental effects to the plant. 

Choline Chloride is already approved for use by EPA as an inert ingredient in pesticide products 

without numeri cal limitation for preharvest food (as a solvent under 40 CFR 180.920) and 

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nonfood uses. Furthermore, Choline Chloride is designated as GRAS (Generally Recognized as 

Safe) and is approved by the Food and Drug Administration (FDA) as a human nutrient under 2 l 

CFR 182.8252 and as a nutrient in animal feed under 2 1 CFR 582.5252. 

Background 

Choline Chloride was classified as a biochemical pesticide by the Biochemical Classification 

Committee (BCC) on April I 0. 2014, due to its natural occurrence. history of exposure to 

humans and the environment without toxicity and its nontoxic mode of action. The Choline 

Chloride EP is similar to previously registered PGR EPs: It is a foliar spray appl ied directly to 

plants at very low concentrations, appli cations are infrequent and targeted. and intended to 

accelerate plant growth at critical stages of the plant's development. 

On June 4, 20 14, the U.S. Environmental Protection Agency C-EPA") received an application 

from Spring Trading Company on behalf of CP Bio. Inc. for the registration or a new active 

ingredient Choline Chloride with a first food use. On February 4, 2015. EPA announced receipt 

of an application to register products containing a new active ingredient - Choli ne Chloride 

(Volume 80. umber 23. FR page numbers 6085 - 6086). On March 4, 2015. EPA issued a 

notice pursuant to f-FDCJ\ section 408( d)(J ), 2 1 U.S.C. 346a( d)(J ), announcing the ti ling of a 

pesticide tolerance petition (PP 4F8287) by CP Bio. Inc. (Volume 80. Number 42. fR page 

numbers 11611 -11614). That document referenced a summary or the petition prepared by the 

petitioner CP Bio. Inc .. which is available in Docket ID umber EPA-1IQ-OPP-20 15-0023 via 

h11p: 11·1nr.r e<s11/atio11s. !!OI'. No substantive comments were submitted in response to either 

announcement. 

Eva lu ation 

In C\'al uming a pesticide registration appli cation. the EP/\ assesses a wide variety orpcsti cide-

-;pccilic information including where and ho\\' the pcsti ciue is used. e1wiron1m:ntal fotc (ie .. 

\\.hat happens to the pesti cide once it" s applied). and toxi city studies (i. e .. effects on humans and 

other nontargct organisms) to determine the likclihoou or aun::rsc effects (i.e .. risk) from 

c:-:posurcs associated 'vvith the proposed use or the product. Risk assessrnents arc developed to 

evaluate the Cll\'ironmenta l fate or the compound as we ll as he)\\ it might affect a\\ idc range or 

nontargct organisms including humans and terrestrial and aquatic wilclli l"e (plants and ani mals). 

On the basis or these assessments. EPJ\ evaluates and approves language l\.)1· each pesticide label 

tn ensure the directions for use and snlcty measures arc appropriate to mitigntc potential risk. In 

this \\H). the pcstieidc·s label helps to communicate essential limitations and mitigations that an: 

neccss<iry for public saf'ct). It is a FIFR1\ 'iolation to use a pesticide in a \\U) that is inconsistent 

\\'ith th e label. 

The human health and environmental risk assessments (including an endangered species 

assessment) supporting this decision as well as the draft labeling can be found in the regul atory 

docket (Document ID: EPJ\-HQ-OPP-2015-0023). 

Assessment of Risk to Human Health 

EPA requires a wide range of studies in order to assess a pesti cide. For Choline Ch loride. the 

database or studies supporting the assessment of risk to human health is particularly robust. As a 

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Jong-standing FDA approved food supplement and an oil-studied PGR, there is a voluminous 

amount of peer-reviewed scientific literature indicating that Choline Chloride is nontoxic and 

that it docs not pose a dietary risk or a risk through any other route of exposure. 

The scicntilic literature notwithstanding. all Tier I mammalian acute toxicology data 

requirements were satisfied by OCSPP guideline studies. All ac ute toxicity studi es indicate that 

Choline Chloride is not acutely toxic for any routes of exposure: it is classified as Toxicity 

Category 111 for acute oral exposure; Toxicity Category IV for dermal and inhalation exposure: 

and it is not a dermal or eye irritant. Specifically, Choline Chloride had: a LDso > 1,750 mg/kg 

(rat) for acute oral toxicity; a LDso> 5.050 mg/kg (rat) for acute dermal toxicity; and a LCso > 

2.03 mg/L (rat) for acute inhalation toxicity. o toxic endpoints were established for any 

exposure. Eye irritation was determined to be minimal; no dermal irritation was noted; and the 

substance is not a dermal sensitizer. The Signal Word for both the Manufacturing-use Product 

(M P) and the End-use Product (EP) is "Caution.'' 

The information submitted in support or the application for the active ingredient Choline 

Chloride indicate that it is not subchronically toxic. Subchronic oral toxicity data requirements 

were satisfi ed through the open scientific literature. Two studi es, a 2 1-day study and a 28-day 

oral toxicity study, were assessed and found to collecti vely satisfy the subchronic oral data 

requirement. Both studies confirm a lack of adverse effects through the oral exposure. 

In the 21-day oral toxicity study (rat), body weight and food consumption were unaffected in the 

test animals. A small beneficial effect was observed relative to the generation of membranous 

phospholipids. /\. no-observed-adverse-effect-level (NOAEL) for the study is 1,000 mg/kg, the 

highest dose tested. In a 28-day oral toxicity study (mice), the results of the study indicated no 

adverse effects for any or the parameters tested. The NOA EL for the study is 200 mg/kg/day. 

which was the highest dose tested. 

Subchroni c dermal and inhalation toxicity data requirements were waived. Per 40 CFR 

158.2050. these requirements are 'Conditionally Required' (CR) based on exposure. In the case 

of the subchroni c dermal toxicity data requirement, the requirement was waived because there is 

no ' purposeful appli cation' to humans and 'prolonged exposure to the human skin' is not 

anti cipated. Choline Chloride is a PGR that \Viii be applied to growing crops infrequently and at 

low concentrations. The subchronic inhalation toxicity data requirement was waived because no 

'signilicant repeat inhalation exposure to the active ingredient as a gas, vapor or aerosol' is 

anticipated. Choline is a salt with a low vapor pressure and volatility; and again, it will be 

applied inl"requently and at lo\v concentrations. 

Mutagenicity data from the open scientific literature satisfy the mutagenicity data requirements 

for holine Chloride. In three separate Ames assays, strains of Salmonella typhimurium were 

exposed to Choline Chloride at up to I 0,000 μg/plate with or without metabolic activation. 

Choline Chloride was not considered mutagenic in any of the assays. 

/\.developmental toxicity study on mice from the open scientific literature satisfies the 

deve lopmental toxicity data requirement for Choline Chloride. In the study, no adverse effects 

were observed at the limit dose of 1250 mg/kg, establishing a NOAEL for maternal and 

developmental toxicity at 1250 mg/kg. 

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Additionally. EPA has not found Choline Chloride to share a common mechanism of toxicity 

with any other substances; and Choline Chloride does not appear to produce a toxic metabolite 

produced by other substances. 

Given the demonstrated lack of adverse effects on humans. a qualitative assessment of Choline 

Chloride is considered suflicient. Humans are already regularl y exposed to Choline Chloride. 

The substance is produced endogenously, and is a regular part of the human diet. Moreover. 

di etary exposure to the residues of Choline Chloride is expected to be negligible. The acti ve 

ingredient will be used at low concentrations because use at high concentrations results in 

detrimental effects to plants (as is the case with most PGRs). /\!so. Choline Chloride is expected 

to biodegrade rapidly once applied. In a MITI-1 test. the substance degraded 93% within 14 days. 

Finally, as a salt. Choline Chloride dissociates readily when in water, making its persistence as a 

residue even more unlikely. (It has a measured water solubility of 650 g/L.) Due to the infrequent 

applications, low application rate. high solubility and biodegradability. the pesticidal use or 

Choline Chloride is not anticipated to contribute significantly to human exposure beyond 

existing background levels. 

Choline Chloride is intended for food use. and is to be supported by an exemption from the 

requirement of a tolerance. Accordingly, the human health assessment for Choline Chloride 

specifically considers dietary risk, which is also largely premised on the overall nontoxicity and 

lack of human exposure discussed above. However, additional dietary risk considerations can be 

found in detail in the accompanying rule for Choline Chloride. In brief, the di etary assessment 

makes the fo llowing dietary risk-specific findings. which are relevant to the general human 

health assessment: Choline Chloride poses no aggregate risk (including, food exposure, drinking 

water exposure, and non-occupational exposure): it poses no cumulative risk relati ve to 

sub lances with common mechanisms of toxicity: and data have been determined to be 

supportive of a safoty finding, protective of special populations, including infants and children. 

Details or the di etary risk assessment can be found in the rule establishing an exemption of the 

requirement of a tolerance for Choline Chloride, and its associated documents. Those documents 

can be found in the regulatory docket - Docket ID Number EP A-HQ-OPP-20 15-0023. 

Assessment of Ecological Risk 

Environmental Fate 

Environmental fa te and groundwater data are not required at this time because the results of the 

nontarget organism toxi city assessment (Tier I data requirements) did not trigger these Tier 11 

data requirements. However, as referred to above. Choline Chloride is not expected to persist in 

the environment. Choline Chloride is highly soluble, dissociating into nontoxic constituents upon 

contact with moisture; and it biodegracles rapidly, degrading 93% within 14 days. 

Environmental Effects 

The ava il able battery of tests required to assess rhe ecological effects of Choline Chloride is 

adequate to conduct an ecological risk assessment. Al I nontarget toxicology data rcqui rements 

(per 40 CfR 158.2060) have been satisfi ed from the open scientifi c literature. Both guideline and 

non-guide! ine freshwater fish studies were cited from the open sci en ti fie literature. The studies 

indicate that Choline Chloride is practically nontoxic to freshwater fish. and establish a 96-hour 

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LCso > 10000 mg/I. Likewise, both guideline and non-guideline studies were cited from the 

open scientific literature to satisfy the data requirement for aquatic invertebrate toxicity. The 

studies indicate that Choline Chloride is practically nontoxic to aquatic invertebrates, and 

establish a 48-hour ECso > 500 mg/I and a NOEC of 125 mg/I. With regard to avian acute oral 

toxicity and avian dietary toxicity, several non-guideline studies demonstrate Choline Chloride's 

nontoxicity through the oral route of exposure. Indeed, the studies actually indicate that Choline 

Chloride can have beneficial effects for birds: increases in body weights and growth; decreases 

in the incidence of perosis (leg deformity); and increases in egg weights and egg production. The 

data requirements for te1Testrial plant toxicity-seedling emergence and terrestrial plant toxicityvegetative vigor were satisfied by several non-guideline studies from the open scientific 

literature. Those studies demonstrate that Choline Chloride, as a PGR, can confer beneficial 

effects to plants by increasing shoot height, leaf area, leaf ratio, chlorophyll content and root 

elongation. Finally, with regard to nontarget insect data requirements, adequate non-guideline 

studies from the open scientific literature were cited, demonstrating that Choline Chloride is 

practically nontoxic to nontarget insects, including honey bees. An acute contact honey bee 

toxicity study established a LOSO of> 89 μg a.i./bee. 

An endangered species assessment on Choline Chloride further quantifies Choline Chloride's 

nontoxicity to nontarget organisms and makes clear that significant exposure to nontarget 

organisms is not anticipated. Per label directions, Choline Chloride is used infrequently and at 

low rates; furthermore, Choline Chloride's high solubility and rapid biodegradation preclude any 

prolonged exposure. The assessment also demonstrates that nontarget exposures will effectively 

be de minimus and that no effects are anticipated. The T-REX model produced low dose-based 

values and risk quotients (RQs) that were at least one to two orders of magnitude (0.00 - 0.06) 

below the EPA Levels of Concern (LOC) ofO.l for avian and mammalian endangered species. 

For aquatic species. the FIRST Ver 1.1.1 model calculated RQ values at 0.00, showing no acute 

toxicity risk. With regard to nontarget plants, the endangered species assessment calculates drift 

residues of 0.63 - I 0.15 ppm on adjacent vegetative sites, a concentration at or below 

background levels (28 - 589 ppm), and considered to be effectively inconsequential. Due to 

Choline Chloride's nontoxic mode of action (as a PGR), rapid rate of biodegradability (7 day 

half-life). rapid rate of photo-degradation (6.9 hours), low rate of bioaccumulation (Log Koc = 

0.37) and low potential for exposure (maximum application of 0.282 lbs ai/A 4 times /season), 

the Agency has made a "No Effect" determination for direct and indirect effects to all listed 

species and their habitats. 

Alternatives 

While there are other PGRs, they are not all functionally equivalent, nor directly interchangeable 

with Choline Chloride. However, as with most PGRs, Choline Chloride is expected to generall y 

reduce the amount of conventional fungicides and insecticides required for commercial crop 

production. By producing stronger and healthier plants, this active ingredient will allow the 

target plant/crop to better resist insects and disease, thereby diminishing the need for 

conventional pesticide appli cations. 

Benefits 

By definition, biochemicals are favorable when compared to currently registered conventional 

alternatives because biochemicals are naturally-occurring substances (or substances structurallyPage 6 of7 
similar and functionally identical lo naturally-occurring substances) with a history of exposure to 

humans and the environment demonstrating minimal toxicity and a nontoxic mode or action to 

the target pest(s). Benefits of biochemical pesticides as compared to conventional pesticides 

typically include lower toxicity profiles for humans and nontarget organisms, and fasler 

degradation in the environment. And as outlined above. Choline Chloride has Lhe potential to 

reduce the amount of more toxic conventional pesticide applications by producing more robust 

stress- resistant plants. 

Public Comments 

On r:ebruary 4, 20 15. EPA announced receipt of an application in the Federal ReKister to 

register a Manufactu ring-use Product (Choline Chloride Technical) and an End-use Product 

(Choline Chloride EUP 20%) containing a new active ingredient. Choline Chloride (Volume 80, 

umber 23, FR page numbers 6085 - 6086). o substantive comments were received in 

response to this Notice of Receipt. 

On March 4, 2015, the EPA issued a noti ce pursuant lo FFDCA section 408(d)(3). 2 1 U.S.C. 

346a(d)(3). announcing the filing of a pesticide tolerance petition (PP 4F8287) by CP Bio, Inc. 

(Volume 80, umber42, FR page numbers 11 611 -11 6 14). The petition requested that 40 CFR 

part 180 be amended by establishing an exemption from the requirement of a tolerance for 

residues of Choline Chloride in or on all food commodities (when applied preharvest). That 

document referenced a summary of the petition prepared by the petitioner CP Bio, Inc., which is 

available in Docket ID umber EPA-HQ-OPP-2015-0023 via '1110: 11·1nr.rc:g11/utiom.<;0L o 

substantive comments were received in response to this otice of r:iling. 

Proposed Regulatory Decision 

The Choline Chloride database is considered to be complete, and supports a pesticidal food use. 

In considering the assessed risk to human health and the environment. the Agency concludes that 

Choline Chloride meets the regulatory standard under the Federal Insecticide. fungicide and 

Rodenticide Act (FIFRA). There are no outstanding data requirements for this biochemical. 

Therefore. the EPA is proposing to grant the unconditional registration of Choline Chloride as a 

new active ingredient food use under Section 3(c)(5) of FIFRA. 

Two products are proposed to be registered: Choline Chloride Technical is a Manulaccuring-use 

Product (MP) and Choline Chloride SP 20% is an End-use Product (EP). Appli cations of the EP 

can be made 3-4 times per season. The EP is formulated as a soluble powder and conta ins 20% 

Choline Chloride. The powder is mixed with water and applied by foliar spray. The EP is 

proposed to be labelled for use on fruiting vegetables. cereal grains, stone fruit, tree nuts and 

cotton. The EP is to be applied at application rates ranging from 0.0004 to 0.282 lb ai/A. 

The human health and ecological risk assessments supporting this decision as we! I as the draft 

labeling can be found in the regulatory docket (Docket ID EPA-HQ-OPP-20 15-0023). 

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