Deltamethrin (Ref: OMS 1998)

Deltamethrin (Ref: OMS 1998)	Last updated: 23/10/2024
(Also known as: decamethrin; deltamethrine; AE F032640)

SUMMARY

Deltamethrin is a pyrethroid insecticide and veterinary treatment that is approved for use in the EU, Australia and the USA. It has a low aqueous solubility, is semi-volatile and has a low potential to leach to groundwater. It is not persistent in soil and is non-mobile. Deltamethrin is highly toxic to humans and other mammals and is a neurotoxin. It is relatively non-toxic to birds and earthworms although it presents a high risk to most aquatic organisms and honeybees.

GENERAL INFORMATION

Description

A pyrethroid insecticide with veterinary applications

Availability status

Current

Introduction & key dates

1974, first described

Examples of veterinary uses

Used to eradicate external parasites on farm animal, domestic pets and fish.

Examples of species treated

Cattle; Fish; Dogs; Cats

Approval status

VMR 2013/2033 approval status (GB/UK)

Approved

EU Regulatory approval status

Approved

Chemical structure

Isomerism

A chiral molecule. Deltamethrin is the cis-isomer of 8 stereoisomeric esters of the dibromo analogue of chrysanthemic acid.

Chemical formula

C₂₂H₁₉Br₂NO₃

Canonical SMILES

CC1(C(C1C(=O)OC(C#N)C2=CC(=CC=C2)OC3=CC=CC=C3)C=C(Br)Br)C

Isomeric SMILES

CC1([C@H]([C@H]1C(=O)O[C@H](C#N)C2=CC(=CC=C2)OC3=CC=CC=C3)C=C(Br)Br)C

International Chemical Identifier key (InChIKey)

OWZREIFADZCYQD-NSHGMRRFSA-N

International Chemical Identifier (InChI)

InChI=1S/C22H19Br2NO3/c1-22(2)17(12-19(23)24)20(22)21(26)28-18(13-25)14-7-6-10-16(11-14)27-15-8-4-3-5-9-15/h3-12,17-18,20H,1-2H3/t17-,18+,20-/m0/s1

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
deltamethrin	Isomer

General status

Veterinary substance type

Insecticide

Metabolite Type

Soil

Other bioactivity & uses

Biocide, Wood preservative

Substance groups

Pyrethroid insecticide; Pyrethroid ester insecticide

Minimum active substance purity

985 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Non-systemic with contact and stomach action. Sodium channel modulator.

Molecular targets

[Sodium channel, Modulator]

CAS RN

52918-63-5

EC number

258-256-6

CIPAC number

333

US EPA chemical code

978051

PubChem CID

40585

CLP index number

607-319-00-X

Therapeutic Class

Antiparasitic products, insecticides & repellents: Ecoparasiticides, insecticides & repellents

ATCvet Code

QP53AC11

Controlled Drug?

Regulation 37/2010 MRL Classification

Allowed substance (Table 1: Ruminants, Fin fish)

Molecular mass

505.2

PIN (Preferred Identification Name)

(S)-cyano(3-phenoxyphenyl)methyl (1R,3R)-3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropane-1-carboxylate

IUPAC name

(S)-α-cyano-3-phenoxybenzyl (1R,3R)-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate

CAS name

(S)-cyano(3-phenoxyphenyl)methyl (1R,3R)-3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropanecarboxylate

Other status information

Marine pollutant

Relevant Environmental Water Quality Standards

Physical state

Colourless crystals

Can be a metabolite of:

Parent

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

tralomethrin

Soil

0.400

Major fraction

Formulations

Property

Product

Manufacturer

Authorisation Route

Legal Class (GB/UK)

Example products (past and present) using this active

AMX 10 mg/ml concentrate for fish treatment

Pharmaq A.S.

GB National authorisation

Prescription only medicine to be authorised by suitably qualified person (POM-VPS)

Butox Swish Pour On Suspension

MSD Animal Health UK Ltd

UK National authorisation

Prescription only medicine to be authorised by suitably qualified person (POM-VPS)

Canishield Medicated Collar

Beaphar B.V.

GB National authorisation

For non-food animal use and may be supplied without a prescription by a suitable qualified person (NFA-VPS)

Scalibor Protectorband Collar

MSD Animal Health UK Ltd

GB National autghorisation

For non-food animal use and may be supplied without a prescription by a suitable qualified person (NFA-VPS)

Formulation and application details

Formulated for topical use as, for example, pour-ons, cutaneous sprays and impregnated collars

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.0002

Low

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

450000

Acetone

175000

Xylene

8150

Methanol

2470

n-Heptane

Melting point (°C)

101

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

Flashpoint (°C)

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

3.98 X 10⁰⁴

Calculated

Log P

4.6

High

Fat solubility of residues

Solubility

Soluble

Data type

Regulatory data - observed in metabolism and farm animal feeding studies

Density (g ml⁻¹)

0.55

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.0011

Low volatility

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

3.10 X 10^-02

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

Negligible

From soil surface

Negligible

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

267, 271 and 278nm, Low to very low absorption at 290-300nm

Surface tension (mN m⁻¹)

Refractive Index

Environmental release

Degradation

Property

Value

Source; quality score; and other information

Interpretation

Soil degradation (days) (aerobic)

DT₅₀ (typical)

58.2

Moderately persistent

DT₅₀ (lab at 20 °C)

28.2

Non-persistent

DT₅₀ (field)

Non-persistent

DT₉₀ (lab at 20 °C)

Moderately persistent

DT₉₀ (field)

Note

EU dossier 2017 lab studies (normalised) DT₅₀ range 12.5-231 days, Soils=22; EU 2002 dossier Lab studies DT₅₀ range 18-35 days, DT₉₀ range 58-117 days, field studies DT₅₀ 1-4 wks with realistic estimate of 3 wks (Germany), DT₉₀ estimates range 1 month to 1 year; Other sources: 104 days (DW4)

Manure DT₅₀ (days)

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Note

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

Value

Stable

Note

pH sensitive: Stable pH 5 to pH 7, DT₅₀ 8 to 9 days at pH 9, 20 °C

Water-sediment DT₅₀ (days)

Moderately fast

Water phase only DT₅₀ (days)

Slow

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

[Wheat grain: >50 wks @ 30 DegC, 50% RH; Modelled data], [Wheat grain (dried): 88.5 days @ ~25 DegC, ~80% RH; Lab study], [Rice: 24.4 days @ -20 DegC; Lab study]

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

Non-mobile

K_oc (mL g⁻¹)

10240000

Notes and range

EU dossier K_oc range 460000-16300000 mL g⁻¹

Freundlich

K_f (mL g⁻¹)

17500

Non-mobile

K_foc (mL g⁻¹)

10240000

¹/_n

0.93

Notes and range

EU 2017 dossier kfoc range 460000-16300000 mL g⁻¹, ¹/_n range 0.74-1.2, Soils=4

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-3.98

Calculated

Low leachability

Bio-concentration factor

BCF (l kg⁻¹)

1400

Threshold for concern

CT₅₀ (days)

Not available

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

decamethrinic acid (Ref: AE F108565)

Major fraction

0.520

3-phenoxybenzoic acid

Minor fraction

0.056

Bayer verified

3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropanecarboxylic acid (Ref: Br2CA)

Major fraction

0.230

Bayer verified

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)

3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropanecarboxylic acid (Ref: Br2CA)

Not relevant

3-phenoxybenzoic acid

Not relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

3-(4-hydroxyphenoxy)benzoic acid

4'HO3PBA

Plant; Animal

4-hydroxydeltamethrin

Plant

0.003

3-phenoxybenzoic acid

Animal

0.03

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

Rat

High

Mammals - Short term dietary NOEL

(mg kg⁻¹)

2.5

Rat

High

(ppm diet)

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

18.3

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5620 ppm

Colinus virginianus

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

> 55

Colinus virginianus NOAEL

Moderate

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

> 645

Eisenia foetida corr

Moderate

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

0.165

Eisenia foetida corr

Moderate

Soil micro-organisms

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

Dose: 0.375 kg ha⁻¹

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

16.0

Folsomia candida corr

Non-target plants

Honeybees (Apis spp.)

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

0.0015

Apis mellifera

High

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

0.07

Apis mellifera

High

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

Chronic as 10-day LDD₅₀ µg bee⁻¹ day⁻¹

> 0.0837

Apis mellifera

Notes

[The residual time to 25% mortality (RT25) value for honeybees is 16.5 hrs (range 10-34 hrs) - USEPA data]

Bumblebees (Bombus spp.)

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

> 0.2

Bombus terrestris

High

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

> 0.61

Bombus terrestris

High

Mason bees (Osmia spp.)

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

0.057

Osmia bicornis

High

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)

0.556

Megachile rotundata

High

Mode of exposure

Contact

Other bee species (2)

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

0.0074

Nomia melanderi

High

Mode of exposure

Contact

Beneficial insects (Ladybirds) as Mortality LD₅₀ ug/g bw insect

0.8

Coccinella septempunctata Larva

Beneficial insects (Lacewings) as Mortality, Contact LC₅₀ ppm

> 3.5

Chrysoperla carnea Larva

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

1.726

Aphidius rhopalosiphi

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

0.00439

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)

0.00015

Oncorhynchus mykiss

High

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

< 0.000032

Oncorhynchus mykiss

High

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

0.00008

Danio rerio

High

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

0.00056

Daphnia magna

High

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

0.0000041

Daphnia magna

High

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

> 0.00004

Ceriodaphnia dubia

High

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

0.0000017

Americamysis bahia

High

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

0.039

Chironomus spp. 24 hr

High

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

0.01

Chironomus riparius

Moderate

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

0.004

Chironomus riparius

High

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

> 0.000405

Lemna gibba

High

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

> 0.00047

Navicula pelliculosa

High

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

Mesocosm study data

NOEAEC mg l⁻¹

0.0032

Aquatic community

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)

Rat

High

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.6

Rat 6 hr (aerosol whole body)

Other Mammal toxicity endpoints

Intraperitoneal LD₅₀ = 10.0 mg kg⁻¹

Mouse

Intravenous LD₅₀ = 2.53 mg kg⁻¹

Rat

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

0.01

Dog SF=100

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

0.025

Dog SF=100

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

0.019

Dog SF=133

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

0.0075

Dog 90 day SF=100

Dermal penetration studies (%)

2-10

concentration and formulation dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Slight risk of dietary exposure for small children however ARfD would not normally be exceeded

Occupational

PPE/PPC recommended

Mammalian dose elimination route and rate

Rapidly metabolised in rats, excreted via urine and faeces, circa 75% eliminated within 24 hr of dose

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

Eye irritant

Phototoxicant

General human health issues

IARC Group 3 carcinogen - not classifiable
Endocrine issues - Weak estrogenic activity

Handling issues

Property

Value and interpretation

General

IMDG Transport Hazard Class 6.1
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H301, H331
Environment: H400, H410

WHO Classification

II (Moderately hazardous)

UN Number

UN2811

Waste disposal & packaging

Packaging Group II (moderate danger)

Shelf-life, storage, stability and reactivity

Chemically stable under standard ambient conditions. Limited shelf-life.

TRANSLATIONS

Language

Name

English

deltamethrin

French

deltamethrine

German

Deltamethrin

Danish

deltamethrin

Italian

deltametrina

Spanish

deltametrin

Greek

deltamethrin

Polish

deltametryna

Swedish

deltametrin

Hungarian

deltamethrin

Dutch

deltamethrin

Norwegian

deltametrin

Record last updated:	23/10/2024
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