Pymetrozine (Ref: CGA 215944)

Pymetrozine (Ref: CGA 215944)	Last updated: 21/08/2024
(Also known as: pimetrozin)

SUMMARY

Data alerts

The following alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement.

Environmental fate	Ecotoxicity	Human health
Environmental fate Moderate alert: Drainflow: Slightly mobile; Potential for particle bound transport: Medium	Ecotoxicity Moderate alert: Birds chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Bees acute oral ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health High alert: Reproduction/development effects

GENERAL INFORMATION

Description

An azomethine insecticide suitable for use in integrated crop management to control aphids and other plant sucking pests

Example pests controlled

Pollen beetles; Aphids; Whiteflies

Example applications

OSR; Potatoes; Brassicas; Spinach; Cucumbers; Ornamentals

Efficacy & activity

Availability status

Current

Introduction & key dates

1992, first reported; 1993, first introduced

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Expired

UK LERAP status

No UK approval for use

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Germany/Belgium

Date EC 1107/2009 inclusion expires

Expired

EU Candidate for substitution (CfS)

Not applicable

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
		✓	✓		✓	✓

Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries

ISIceland	NONorway

Additional information

Also used in

Chemical structure

Isomerism

Isomeric

Chemical formula

C₁₀H₁₁N₅O

Canonical SMILES

CC1=NNC(=O)N(C1)N=CC2=CN=CC=C2

Isomeric SMILES

CC1=NNC(=O)N(C1)/N=C/C2=CN=CC=C2

International Chemical Identifier key (InChIKey)

QHMTXANCGGJZRX-WUXMJOGZSA-N

International Chemical Identifier (InChI)

InChI=1S/C10H11N5O/c1-8-7-15(10(16)14-13-8)12-6-9-3-2-4-11-5-9/h2-6H,7H2,1H3,(H,14,16)/b12-6+

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
pymetrozine	-
pymetrozine hydrate	Variant

General status

Pesticide type

Insecticide

Substance groups

Pyridine insecticide; Azomethine insecticide

Minimum active substance purity

970 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Selective, neural inhibition of feeding behavior that eventually starves insect. Chordotonal organ TRPV channel modulator.

CAS RN

123312-89-0

EC number

602-927-1

CIPAC number

593

US EPA chemical code

101103

PubChem CID

9576037

CLP index number

613-202-00-4

Molecular mass

217.23

PIN (Preferred Identification Name)

IUPAC name

(E)-4,5-dihydro-6-methyl-4-(3-pyridylmethyleneamino)-1,2,4-triazin-3(2H)-one

CAS name

4,5-dihydro-6-methyl-4-((E)-(3-pyridinylmethylene)amino)-1,2,4-triazin-3(2H)-one

Other status information

Chemical subject to PIC regulations: GB Part 2

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Not applicable

Herbicide Resistance Class (WSSA MoA class)

Not applicable

Insecticide Resistance Class (IRAC MoA class)

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Bemisia tabaci

Physical state

White to light brown coloured crystals

Formulations

Property

Value

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

Syngenta

Example products using this active

Chess
Plenum
Endeavour
Fulfill

Formulation and application details

Often supplied as wettable granules 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)

270

at 25 °C

Moderate

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

1000

n-Hexane

34000

Toluene

940000

Acetone

260000

Ethyl acetate

Melting point (°C)

Decomposes before melting

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

217

Flashpoint (°C)

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

6.46 X 10^-01

Calculated

Log P

-0.19

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

1.37

Dissociation constant pKa) at 25 °C

4.06

Weak acid

Vapour pressure at 20 °C (mPa)

4.20 X 10^-03

Low volatility

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

3.00 X 10^-06

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

24 hr

Volatilisation is not considered critical for air pollution

From soil surface

24 hr

Volatilisation is not considered critical for air pollution

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

246nm=9500, 299.2nm = 20500

Surface tension (mN m⁻¹)

68.4

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Non-persistent

DT₅₀ (lab at 20 °C)

4.6

Non-persistent

DT₅₀ (field)

22.6

Non-persistent

DT₉₀ (lab at 20 °C)

Moderately persistent

DT₉₀ (field)

320.7

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 2.05-29.2 days, DT₉₀ range 8.3-96.9 days, field studies DT₅₀ range 3.81-183 days, n=8, DT₉₀ range 65.2 - >1000 days

Dissipation rate RL₅₀ (days) on plant matrix

Value

2.5

Note

Lettuce head, n=1

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

2.48

Note

Published literature RL₅₀ range 0.9-4.2 days, 5 field crops, various matrices, n=5

Aqueous photolysis DT₅₀ (days) at pH 7

Value

6.8

Moderately fast

Note

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

Value

Stable

Note

DT₅₀: 8.6 days at pH 5, stable pH 7 and pH 9, all at 25 °C

Water-sediment DT₅₀ (days)

Moderately fast

Water phase only DT₅₀ (days)

Moderately fast

Air degradation

As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.

Decay in stored produce DT₅₀

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

19.3

Slightly mobile

K_foc (mL g⁻¹)

1049

¹/_n

0.880

Notes and range

EU dossier 2014 K_f range 3.10-47.7 mL g⁻¹, kfoc range 246-3080, ¹/_n range 0.790-0.952, Soils=7

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.33

Calculated

Low leachability

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

Value

2.83 X 10^-02

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk

13.2

Calculated using the Atkinson method. Assumed 1.5E+06 OH/cm³, 12 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

No data

Known soil metabolites

Metabolite

Major/Minor fraction

$Click here for further information on Major/Minor fraction$

Estimated maximum occurrence fraction

Notes

5-hydroxy-6-methyl-4-(((E)-pyridin-3-ylmethylene)amino)-4,5-dihydro-1,2,4-triazin-3(2H)-one (Ref: CGA 359009)

Major fraction

0.537

5-hydroxy-6-methyl-4-(((E)-(6-oxo-1,6-dihydropyridin-3-yl)methylene)amino)-4,5-dihydro-1,2,4-triazin-3(2H)-one (Ref: CGA 363431)

Major fraction

0.238

6-methylene-3-oxo-5,6-dihydro-1,2,4-triazin-4(3H)-aminium (Ref: SYN 505866)

Minor fraction

0.066

6-methyl-4-((6-oxo-1,6-dihydropyridine-3-ylmethylene)-amino)4,5-dihydro-2H-(1,2,4)triazin-3,5-dione (Ref: CGA 363430)

Major fraction

0.100

4,6-dimethyl-1,2,4-triazine-3,5(2H,4H)-dione (Ref: CGA 371075)

Minor fraction

0.076

6-oxo-1,6-dihydropyridine-3-carbaldehyde (Ref: CGA 255548)

Major fraction

0.137

4-amino-6-methyl-1,2,4-triazine-3,5(2H,4H)-dione (Ref: CGA 294849)

Major fraction

0.132

Aerobic

4-amino-6-methyl-1,2,4-triazin-3(2H)-one (Ref: CGA 215525)

Minor fraction

0.087

pyridine-3-aldehyde (Ref: CGA 300407)

Major fraction

0.144

Known groundwater metabolites

Metabolite

EC SANCO/221/2000 relevancy

ADI (mg kg⁻¹ bodyweight day⁻¹)

WHO drinking water guidance value (μg L⁻¹ day⁻¹)

6-oxo-1,6-dihydropyridine-3-carbaldehyde (Ref: CGA 255548)

Relevancy unknown

4-amino-6-methyl-1,2,4-triazin-3(2H)-one (Ref: CGA 215525)

Relevancy unknown

4-amino-6-methyl-1,2,4-triazine-3,5(2H,4H)-dione (Ref: CGA 294849)

Relevancy unknown

4,6-dimethyl-1,2,4-triazine-3,5(2H,4H)-dione (Ref: CGA 371075)

Relevancy unknown

6-methyl-4-((6-oxo-1,6-dihydropyridine-3-ylmethylene)-amino)4,5-dihydro-2H-(1,2,4)triazin-3,5-dione (Ref: CGA 363430)

Relevancy unknown

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

4-amino-6-methyl-4,5-dihydro-1,2,4-triazin-3(2H)-one (Ref: CGA 215525)

Water (Hydrolysis)

0.480

pyridin-3-ylmethanol (Ref: CGA 128632)

Plant

3,5-dioxo-2,3,4,5-tetrahydro-1,2,4-triazine-6-carboxylic acid (Ref: CGA 266591)

Plant

6-methyl-4,5-dihydro-1,2,4-triazin-3(2H)-one (Ref: CGA 249257)

Water (Photolysis)

0.210

nicotinaldehyde (Ref: CGA 300407)

Water (Hydrolysis)

0.630

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

5820

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

3.7

Rat 2 yr

High

(ppm diet)

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

110

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5200 mg kg feed⁻¹

Anas platyrhynchos

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

21.8

Colinus virginianus NOEL

Moderate

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

1098

Eisenia foetida

Low

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

1.386

Eisenia foetida

Moderate

Soil micro-organisms

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

Dose: 6.66 mg kg⁻¹ soil

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

1000

Folsomia candida

Non-target plants

Honeybees (Apis spp.)

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

> 100

Apis mellifera

Low

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

> 62.7

Apis mellifera

Moderate

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

Chronic

Bumblebees (Bombus spp.)

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

> 100

Bombus terrestris

Low

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

> 70.6

Bombus terrestris

Moderate

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 bee species (1)

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

Mode of exposure

Other bee species (2)

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

Mode of exposure

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings) as Mortality LR₅₀ g ha⁻¹

> 2400

Chrysoperla carnea

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g ha⁻¹

> 1200

Aphidius colemani Adult

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹

> 1200

Typhlodromus pyri

Beneficial insects (Ground beetles) as Morality LR₅₀ g ha⁻¹

> 1200

Poecilus cupreus

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 100

Oncorhynchus mykiss

Low

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

> 11.7

Oncorhynchus mykiss

Low

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

3.79

Danio rerio EC₅₀ Embryo

Moderate

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

Daphnia magna

Moderate

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

0.025

Daphnia magna

Moderate

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

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

61.7

Americamysis bahia EC₅₀

Moderate

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

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

0.313

Chironomus riparius 30 day

Moderate

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

18.8

Chironomus riparius 30 day

Moderate

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

106

Lemna gibba

Low

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

21.6

Raphidocelis subcapitata

Low

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

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)

5820

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 1.8

Rat

Other Mammal toxicity endpoints

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

0.03

Dog SF=100

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

0.1

Rabbit SF=100

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

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

0.03

Rat 90 day SF=100

Dermal penetration studies (%)

0.05-5%

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

Great Britain

GB MRL Register

Notes

New GB MRL in place from 24 April 2023

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

May affect most major organs at high doses
Highly toxic - harmful if swallowed
US EPA - likely to be human carcinogen; CLP data - suspected carcinogen

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
Non-flammable but is combustible
Not expected to auto-ignite

CLP classification 2013

Health: H351
Environment: H412

WHO Classification

III (Slightly hazardous)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

pymetrozine

French

pymetrozine

German

Pymetrozin

Danish

pymetrozin

Italian

pymetrozine

Spanish

pimetrozina

Greek

pymetrozine

Polish

pymetrozyna

Swedish

pymetrozin

Hungarian

pimetrozin

Dutch

pymetrozine

Norwegian

Record last updated:	21/08/2024
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