Leptophos (Ref: OMS 1438 )

Leptophos (Ref: OMS 1438 )	Last updated: 16/02/2021
(Also known as: VCS 506; MBCP)

GENERAL INFORMATION

Description

An obolete insecticide that is effective against lepidoptera and other insect pests

Example pests controlled

Prodenia litura; Grasshoppers; Fleas; Beetles; Aphids; Thrips

Example applications

Cereals; Cotton; Lawns; Rice; Sugarcane; Sugarbeet; Lettuce; Tomatoes; Tobacco

Efficacy & activity

Availability status

Obsolete

Introduction & key dates

1969, first reported

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Not applicable

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

Not applicable

Date EC 1107/2009 inclusion expires

Not applicable

EU Candidate for substitution (CfS)

Not applicable

Listed in EU database

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

Chemical structure

Isomerism

Leptophos is a chiral molecule. The technical material is an isomeric mixture.

Chemical formula

C₁₃H₁₀BrCl₂O₂PS

Canonical SMILES

COP(=S)(C1=CC=CC=C1)OC2=CC(=C(C=C2Cl)Br)Cl

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

CVRALZAYCYJELZ-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C13H10BrCl2O2PS/c1-17-19(20,9-5-3-2-4-6-9)18-13-8-11(15)10(14)7-12(13)16/h2-8H,1H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
leptophos	-

General status

Pesticide type

Insecticide

Substance group

Organophosphate

Minimum active substance purity

Approx 85% pure

Known relevant impurities

Substance origin

Synthetic

Mode of action

Cholinesterase inhibitor. Non-systemic.

CAS RN

21609-90-5

EC number

244-472-8

CIPAC number

US EPA chemical code

525300

PubChem CID

30709

Molecular mass

412.07

PIN (Preferred Identification Name)

(E)-[O-(4-bromo-2,5-dichlorophenyl) O-methyl phenylphosphonothioate]

IUPAC name

(RS)-(O-4-bromo-2,5-dichlorophenyl O-methyl phenylphosphonothioate)

CAS name

O-(4-bromo-2,5-dichlorophenyl) O-methyl phenylphosphonothioate

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Not applicable

Herbicide Resistance Classification (WSSA)

Not applicable

Insecticide Resistance Classification (IRAC)

Fungicide Resistance Classification (FRAC)

Not applicable

Examples of recorded resistance

Myzus persicae, Plutella xylostella, Spodoptera littoralis, Pectinophora gossypiella

Physical state

White solid

Formulations

Property

Value

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

Phosvel
Velsicol 506

Example products using this active

velsicol

Formulation and application details

Common formulations include emulsifiable concentrates, wettable powders and granules

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

2.4

Low

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

1300000

benzene

470

Acetone

142000

Cyclohexane

Melting point (°C)

70.4

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

Flashpoint (°C)

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

2.04 X 10⁰⁶

Calculated

Log P

6.31

High

Bulk density (g ml⁻¹)

1.53

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

1.999

Low volatility

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

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

Surface tension (mN m⁻¹)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Very persistent

Dissipation rate RL₅₀ on plant matrix

Value

Note

Dissipation rate RL₅₀ on and in plant matrix

Value

6.7

Note

Published literature RL₅₀ range 3.0-17.0 days, 9 field grown crops, various matrices, n=9

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Note

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

Value

38.5

Moderately persistent

Note

pH sensitive: 245 days at pH 6, 38.5 days at pH 7, 16 days at pH 8

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

Non-mobile

K_oc

33000

Notes and range

K_oc range 1175-117490 mL g⁻¹

Freundlich

K_f

K_foc

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

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

Value

Cannot be calculated

Note

Potential for particle bound transport index

Potential for loss via drain flow

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

6058

High potential

CT₅₀ (days)

not available

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

43.0

Rat

High

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)

> 1500

Coturnix japonica

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

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

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 0.011

Oncorhynchus mykiss

High

Fish - Chronic 21 day NOEC (mg l⁻¹)

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

0.002

Daphnia magna

High

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

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

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)

Non-target plants

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

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)

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

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)

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

> 3400

Lumbricus terrestris

Low

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Other arthropod (1)

LR₅₀ g ha⁻¹

% Effect

Other arthropod (2)

LR₅₀ g ha⁻¹

% Effect

Soil micro-organisms

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)

43.0

Rat

High

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

800

Rabbit

Mammals - Inhalation LC₅₀ (mg l⁻¹)

2.7

Rat

Other Mammal toxicity endpoints

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

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

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

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

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

List I

Exposure Routes

Public

Occupational

May occur through dermal contact and inhalation of dust and sprays

MRLs

European

EU MRL pesticide database

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

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

Highly toxic

Handling issues

Property

Value and interpretation

General

Avoid generation of dust
IMDG Transport Code is 6.1

CLP classification 2013

EC Risk Classification

T - Toxic: R25
Xn - Harmful: R21, R39
N - Dangerous for the environment: R50/53

EC Safety Classification

WHO Classification

Ia (Extremely hazardous)

UN Number

2783

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

leptophos

French

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Polish

Swedish

Hungarian

Dutch

Record last updated:	16/02/2021
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