Pyridaben (Ref: BAS 300l)

Pyridaben (Ref: BAS 300l)	Last updated: 14/12/2024
(Also known as: piridabena; NC 129)

SUMMARY

Pyridaben is an insecticide and acaricide. It has a low aqueous solubility, relatively volatile and, based on its chemical properties, is not expected to leach to groundwater. It tends not to persist in soils or water systems. It is moderately toxic to mammals and not expected to bioaccumulate. It is highly toxic to most aquatic organisms and honeybees but less so to earthworms and birds.

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: Potential for particle bound transport: Medium	Ecotoxicity High alert: Fish acute ecotoxicity: High; Fish chronic ecotoxicity: High; Daphnia acute ecotoxicity: High; Daphnia chronic ecotoxicity: High; Bees acute contact ecotoxicity: High; Bees acute oral ecotoxicity: High	Human health Moderate alert: Mammals acute toxicity: Moderate; Reproduction/development effects; Neurotoxicant

GENERAL INFORMATION

Description

An insecticide and acaricide affective against thrips, mites, aphids and leafhoppers

Example pests controlled

Spider mites; Rust mites; Pear Psylla; Whiteflies

Example applications

Field crops; Fruit trees; Strawberries; Ornamentals; Vegetables; Greenhouse crops including cucumbers, tomatoes & peppers

Efficacy & activity

Availability status

Current

Introduction & key dates

1988, first reported; 1990, first marketed Belgium

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

30/04/2026

GB LERAP status

No data

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Czech Republic/Belgium

Date EC 1107/2009 inclusion expires

31/07/2026

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
		✓	✓	✓	✓

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

Australia, Japan, Canada, USA, Morocco

Chemical structure

Isomerism

None

Chemical formula

C₁₉H₂₅CIN₂OS

Canonical SMILES

CC(C)(C)C1=CC=C(C=C1)CSC2=C(C(=O)N(N=C2)C(C)(C)C)Cl

Isomeric SMILES

International Chemical Identifier key (InChIKey)

DWFZBUWUXWZWKD-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C19H25ClN2OS/c1-18(2,3)14-9-7-13(8-10-14)12-24-15-11-21-22(19(4,5)6)17(23)16(15)20/h7-11H,12H2,1-6H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
pyridaben	-

General status

Pesticide type

Insecticide, Acaricide

Substance groups

Pyridazinone insecticide; Pyridazinone acaricide

Minimum active substance purity

980 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Non-systemic with rapid knock down action and long residual activity. Mitochondrial complex I electron transport inhibitor.

CAS RN

96489-71-3

EC number

405-700-3

CIPAC number

583

US EPA chemical code

129105

PubChem CID

91754

CLP index number

613-149-00-7

Molecular mass

364.93

PIN (Preferred Identification Name)

IUPAC name

2-tert-butyl-5-(4-tert-butylbenzylthio)-4-chloropyridazin-3(2H)-one

CAS name

4-chloro-2-(1,1-dimethylethyl)-5-(((4-(1,1-dimethylethyl)phenyl)methyl)thio)-3(2H)-pyridazinone

Other status information

PAN listed Highly Hazardous Chemical

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)

21A

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Tetranychus kanzawai, Tetranychus urticae

Physical state

White crystals

Formulations

Property

Value

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

Nissan Chemicals
Vapco
BASF
Zeneca

Example products using this active

Nexter Pro
Sanmite 75WP
Pyramite
Poseidon
Starling

Formulation and application details

Usually supplied as a wettable powder and suspension concentrates that are mixed with water and applied as a spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.022

Low

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

333000

Acetone

345000

Xylene

49400

Methanol

14100

n-Hexane

Melting point (°C)

109.4

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

200

Flashpoint (°C)

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

2.34 X 10⁰⁶

Calculated

Log P

6.37

High

Fat solubility of residues

Solubility

Soluble

Data type

Regulatory data - observed in metabolism and farm animal feeding studies

Density (g ml⁻¹)

1.2

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.001

Low volatility

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

0.3

Moderately volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Neutral solution 296.5nm = 11746, 236.2nm = 21102, 223.4nm = 23221
Acidic solution: 296.9nm = 11785, 236.3nm= 21142, 223.3nm = 23327
Basic solution 296.6nm = 11724, 236.3nm = 21015, 223.3nm = 23037

Surface tension (mN m⁻¹)

Not applicable

Low aqueous solubility

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Moderately persistent

DT₅₀ (lab at 20 °C)

106

Persistent

DT₅₀ (field)

Non-persistent

DT₉₀ (lab at 20 °C)

1520

Very persistent

DT₉₀ (field)

188

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 50-199 days, DT₉₀ range 241-4522 days; field study DT₅₀ range 5-128 days, DT₉₀ range 98-424 days; Other sources: DT₅₀ 86 days (DW4)

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

6.0

Note

Published literature RL₅₀ range 2.3-11.8 days, 10 field & undercover grown crops, various matrices, n=12

Aqueous photolysis DT₅₀ (days) at pH 7

Value

0.005

Fast

Note

Rapid

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

Value

Stable

Note

Stable pH 5 to pH 9 at 25 °C

Water-sediment DT₅₀ (days)

17.5

Fast

Water phase only DT₅₀ (days)

1.18

Moderately fast

Sediment phase only DT₅₀ (days)

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)

276

Non-mobile

K_foc (mL g⁻¹)

66503

¹/_n

0.95

Notes and range

EU dossier kf range 108-445 mL g⁻¹, K_foc range 34858-87918 mL g⁻¹, ¹/_n range 0.90-1.28, Soils=4

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-1.20

Calculated

Low leachability

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

Value

5.35 X 10^-03

Calculated

Note

Estimated concentrations of chemicals with Koc values greater than 9995 ml g⁻¹ are beyond the scope of the regression data used in SCI-GROW development. If there are concerns for such chemicals, a higher tier groundwater exposure assessment should be considered, regardless of the concentration returned by SCI-GROW

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Non-mobile

Calculated

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

4.8

Calculated using the Atkinson method. Assumed 9.7E+05 OH/cm³, 12 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

Low potential

CT₅₀ (days)

0.8

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

2-tert-butyl-5-(4-(1-carboxy-1-methylethyl) benzylthio)4-chloropyridazin-3 (2H)-one

Minor fraction

0.085

2-tert-butyl-4-chloropyridazin-3(2H)-one-5-sulfonic acid

Minor fraction

0.076

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

2-tert-butyl-4-chloro-5-[4-(1,1-dimethyl-2-hydroxyethyl)benzylthio]-chloropyridazin-3 (2H)-one

PB-9

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

161

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

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

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 4298 mg kg bw⁻¹ day⁻¹

Colinus virginianus

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

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

Eisenia foetida corr

Moderate

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

0.29

Eisenia foetida

Moderate

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

3.28

Folsomia candida

Non-target plants

Honeybees (Apis spp.)

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

0.024

Apis mellifera

High

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

0.535

Apis mellifera

High

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

Chronic

Notes

[The residual time to 25% mortality (RT25) value for honeybees is 20 hrs - USEPA data]; [USEPA LD50 contact reported as 1.81 ug/bee, oral reported as 2.63 ug/bee]

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 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)

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

0.24

Aphidius rhopalosiphi Adult

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

0.59

Typhlodromus pyri

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

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

0.0007

Oncorhynchus mykiss

High

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

> 0.0016

Pimephales promelas 301 day

High

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

0.004

Danio rerio EC₅₀ Embryo

High

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

0.001

Daphnia magna

High

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

0.000086

Daphnia magna

High

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

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

0.00054

Americamysis bahia

High

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)

0.016

Lemna gibba

Moderate

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

0.017

Pseudokirchneriella subcapitata

Moderate

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

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

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)

161

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.62

Rat

Other Mammal toxicity endpoints

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

0.01

Rat SF=100

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

0.05

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)

0.005

Rat SF=10

Dermal penetration studies (%)

0.4-1.2

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Risk to bystanders if they enter greenhouses after spraying

Occupational

No unacceptable risks to operators or other workers identified utilising PPE/PPC

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

0.1

EU Dir 89/778/EC limit; Calc MAC=30 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

Moderately toxic

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 9
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H301, H331
Environment: H400, H410

WHO Classification

II (Moderately hazardous)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

Stable and non-reactive under normal conditions of use, storage and transport

TRANSLATIONS

Language

Name

English

pyridaben

French

pyridabene

German

Pyridaben

Danish

pyridaben

Italian

piridaben

Spanish

piridaben

Greek

Polish

pyridaben

Swedish

Hungarian

piridaben

Dutch

pyridaben

Norwegian

Record last updated:	14/12/2024
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