Trinexapac-ethyl (Ref: CGA 163935)

Trinexapac-ethyl (Ref: CGA 163935)	Last updated: 20/03/2021
(Also known as: trinexapac; cimectacarb-ethyl; cimectacarb)

GENERAL INFORMATION

Description

A novel plant growth regulator used to prevent lodging. Also used on turf and amenity grassland to slow growth.

Example pests controlled

Lodging; Grass growth

Example applications

Cereals including wheat, barley, oats, rye; Oilseed rape; Amenity turf and grass

Efficacy & activity

Availability status

Current

Introduction & key dates

1992, Switzerland

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

30/04/2024

UK LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Lithuania/Latvia

Date EC 1107/2009 inclusion expires

30/04/2021

EU Candidate for substitution (CfS)

Listed in EU database

Yes

Approved for use (✓) under EC 1107/2009 in the following EU Member States

ATAustria	BEBelgium	BGBulgaria	CYCyprus	CZCzech Republic	DEGermany	DKDenmark	EEEstonia	ELGreece
✓	✓	✓		✓	✓	✓	✓	✓
ESSpain	FIFinland	FRFrance	HRCroatia	HUHungary	IEIreland	ITItaly	LTLithuania	LULuxembourg
✓	✓	✓	✓	✓	✓	✓	✓	✓
LVLatvia	MTMalta	NLNetherlands	PLPoland	PTPortugal	RORomania	SESweden	SISlovenia	SKSlovakia
✓	✓	✓	✓	✓	✓	✓	✓	✓

Also used in

Australia

Chemical structure

Isomerism

Chemical formula

C₁₃H₁₆O₅

Canonical SMILES

CCOC(=O)C1CC(=O)C(=C(C2CC2)O)C(=O)C1

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

RVKCCVTVZORVGD-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C13H16O5/c1-2-18-13(17)8-5-9(14)11(10(15)6-8)12(16)7-3-4-7/h7-8,16H,2-6H2,1H3/b12-11-

2D structure diagram/image available?

Yes

General status

Pesticide type

Plant growth regulator

Substance group

Cyclohexanecarboxylate derivative

Minimum active substance purity

940 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Inhibits gibberellin synthesis, slowing growth

CAS RN

95266-40-3

EC number

CIPAC number

732.202

US EPA chemical code

112602

PubChem CID

92421

Molecular mass

252.26

PIN (Preferred Identification Name)

ethyl (RS)-4-cyclopropyl(hydroxy)methylene-3,5-dioxocyclohexanecarboxylate

IUPAC name

ethyl (RS)-4-cyclopropyl(hydroxy)methylene-3,5-dioxocyclohexanecarboxylate

CAS name

ethyl 4-(cyclopropylhydroxymethylene)-3,5-dioxocyclohexanecarboxylate

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Not applicable

Herbicide Resistance Classification (WSSA)

Not applicable

Insecticide Resistance Classification (IRAC)

Not applicable

Fungicide Resistance Classification (FRAC)

Not applicable

Examples of recorded resistance

Physical state

White solid at 996 g/kg or purer. Less pure substance tends to be a reddish brown solid.

Formulations

Property

Value

Example manufacturers & suppliers of products using this active now or historically

Moddus
Stunt
Groslow
Clipless
Cutaway
Duet Max
RegiMax PGR

Example products using this active

AgriGuard
Clayton
Novartis
Pan Agriculture
Scotts

Formulation and application details

Often supplied as emulsifiable or a soluble concentrates that are mixed with water and used as a spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

10200

High

Solubility - In organic solvents at 20 °C (mg l⁻¹)

500000

Acetone

500000

Methanol

45000

Hexane

420000

n-Octanol

Melting point (°C)

36.3

Boiling point (°C)

270

Degradation point (°C)

310

Flashpoint (°C)

156

Octanol-water partition coefficient at pH 7, 20 °C

5.13 X 10^-01

Calculated

Log P

-0.29

at 25 °C

Low

Bulk density (g ml⁻¹)

1.31

Dissociation constant pKa) at 25 °C

4.57

Weak acid

Vapour pressure at 20 °C (mPa)

2.16

Low volatility

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

5.40 X 10^-04

Non-volatile

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

Neutral solution: 240.2nm = 9335, 277.4nm = 13976
Acidic solution: 240.0nm = 11712, 280.4nm = 12368
Basic solution: 270.8nm = 21320

Surface tension (mN m⁻¹)

58.3

at 22.5 °C 99.6%

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

0.16

Non-persistent

DT₅₀ (lab at 20 °C)

0.16

Non-persistent

DT₅₀ (field)

14.6

Non-persistent

DT₉₀ (lab at 20 °C)

0.90

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

0.1

Note

2017 EU dossier lab studies DT₅₀ range 0.045-0.72 days, DT₉₀ range 0.15-2.4 days, soils=5; Field studies from 2005 EU dossier DT₅₀ range 6.9-21 days; Other sources: DT₅₀ 3 days (DW4)

Dissipation rate RL₅₀ on plant matrix

Value

Note

Dissipation rate RL₅₀ on and in plant matrix

Value

1.65, Wheat, whole plant, n=1

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Slow

Note

Data for artificial sunlight, 40 deg N, faster at higher temperatures

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

868

Very persistent

Note

pH sensitive: Stable at pH 5 and pH 7, DT₅₀ 10.9 days at pH 9

Water-sediment DT₅₀ (days)

4.5

Fast

Water phase only DT₅₀ (days)

4.2

Moderately fast

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

K_oc

Notes and range

Freundlich

K_f

5.15

Moderately mobile

K_foc

280

¹/_n

0.94

Notes and range

EU dossier K_f range 0.66-17.8 mL g⁻¹, K_foc range 60-629 mL g⁻¹, ¹/_n range 0.92-1.01, Soils=4

pH sensitivity

Yes - decreased sorption at increasing pH

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.81

Calculated

Transition state

SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate

Value

4.32 X 10^-02

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

Key metabolites

Metabolite

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

trinexapac (Ref: CGA 179500)

Soil

0.867

Major fraction, Relevant

3-ethoxycarbonylpentanedioic acid (Ref: CGA 300405)

Soil

0.125

Major fraction, Relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

Ref: CGA 351210

Plant

Ref: CGA 113745

Plant; Animal

Ref: CGA 275537

Plant

Ref: CGA 329773

Plant

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

Low potential

CT₅₀ (days)

1.4

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

4210

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

> 34

Rat

High

(ppm diet)

> 500

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

≥ 1293

Rat Reproductive NOAEL

Low

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 2000 mg kg feed⁻¹

Anas platyrhynchos

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

53.3

Colinus virginianus NOEL

Moderate

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Ictalurus punctatus

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

0.41

Pimephales promelas 35 day

Moderate

Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

> 142.5

Daphnia magna

Low

Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

2.4

Daphnia magna

Moderate

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

5.8

Americamysis bahia

Moderate

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)

8.8

Lemna gibba

Moderate

Non-target plants

> 760

10 species including lettuce carrot oat onion
Vegetative vigour, ER₅₀
as g ha⁻¹

> 840

10 species including lettuce carrot oat onion
Seedling emergence, ER₅₀
as g ha⁻¹

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

24.5

Pseudokirchneriella subcapitata 96hr

Low

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

Honeybees (Apis spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

> 200

Apis mellifera

Low

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

> 200

Apis mellifera

Low

Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Bumblebees (Bombus spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Mason bees (Osmia spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Other pollinators (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other pollinators (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

> 93

Eisenia foetida

Moderate

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

25.2

Folsomia candida

Other arthropod (1)

LR₅₀ g ha⁻¹

114

48 hour
Aphidius rhopalosiphi adult

% Effect

Other arthropod (2)

LR₅₀ g ha⁻¹

197

7 day
Typhlodromus pyri protonymph

% Effect

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect

Dose: 8.6 mg kg⁻¹ soil 28 days

Mesocosm study data

NOEAEC mg l⁻¹

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

4210

Rat

Low

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

4000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.3

Rat 4 hr (nose only liquid aerosol)

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

0.32

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

None allocated

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

0.34

Dermal penetration studies (%)

25-75

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

No unacceptable risks to operators or other workers identified

MRLs

European

EU MRL pesticide database

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

0.1

EU Dir 89/778/EC limit; Calc MAC=42.0 µg l⁻¹

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

General human health issues

Liver, kidney and brain toxicant

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
Autoignition temperature >300 deg C
IMDG Transport Code is usually 9

CLP classification 2013

Environment: H410, H411, H412

EC Risk Classification

N - Dangerous for the environment: R50, R53

EC Safety Classification

S60, S61

WHO Classification

NL (Not listed)

UN Number

Usually 3082

Waste disposal & packaging

Packaging Group III (minor danger)

TRANSLATIONS

Language

Name

English

trinexapac-ethyl

French

trinexapac-ethyl

German

Trinexapac

Danish

trinexapac-ethyl

Italian

trinexapac-etile

Spanish

trinexapac-etil

Greek

Polish

trineksapak etylu

Swedish

trinexapak etylester

Hungarian

Dutch

trinexapac-ethyl

Record last updated:	20/03/2021
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242