Penoxsulam (Ref: XDE 638)

Penoxsulam (Ref: XDE 638)	Last updated: 26/05/2025
(Also known as: DE 638; DASH-001; DASH-1100)

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: GUS: Transition state; Drainflow: Moderately mobile	Ecotoxicity Moderate alert: Daphnia chronic ecotoxicity: Moderate	Human health Moderate alert: Endocrine disrupter

GENERAL INFORMATION

Description

A post-emergence herbicide used on rice crops for the control of broadleaved weeds, aquatic weeds and certain grasses

Example pests controlled

Sedges; Broadleaved weeds including loosestrife, chickweed and clover; Aquatic weeds including water plaintain and water hyacinth; Certain grasses including barnyardgrass, young watergrass, annual blackgrass and buckwheat

Example applications

Lawns; Rice; Cereals; Orchards; Olives; Chicory

Efficacy & activity

Efficiacy demonstrated from field trials and extensive use

Availability status

Current

Introduction & key dates

2004, registered Turkey

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/07/2026

GB LERAP status

No UK approval for use as a plant protection agent

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Italy/Poland

Date EC 1107/2009 inclusion expires

15/05/2026

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

Chemical structure

Isomerism

None

Chemical formula

C₁₆H₁₄F₅N₅O₅S

Canonical SMILES

COC1=CN=C(N2C1=NC(=N2)NS(=O)(=O)C3=C(C=CC=C3OCC(F)F)C(F)(F)F)OC

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

SYJGKVOENHZYMQ-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C16H14F5N5O5S/c1-29-10-6-22-15(30-2)26-13(10)23-14(24-26)25-32(27,28)12-8(16(19,20)21)4-3-5-9(12)31-7-11(17)18/h3-6,11H,7H2,1-2H3,(H,24,25)/f/h25H

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Sulfonamide herbicide;Trazoloprimidine herbicide

Minimum active substance purity

980 g kg⁻¹

Known relevant impurities

EU 2021 dossier - Bis-CHYMP, < 0.1 g kg⁻¹; 3,5-lutidine < 2 g kg⁻¹

Substance origin

Synthetic

Mode of action

Broad-spectrum, absorbed mainly by leaves and, to lesser extent, roots and translocated, exhibits knockdown and residual control. Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS.

CAS RN

219714-96-2

EC number

606-869-8

CIPAC number

758

US EPA chemical code

119031

PubChem CID

11784975

Molecular mass

483.37

PIN (Preferred Identification Name)

IUPAC name

3-(2,2-difluoroethoxy)-N-(5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)-α,α,α-trifluorotoluene-2-sulfonamide

CAS name

2-(2,2-difluoroethoxy)-N-(5,8-dimethoxy(1,2,4)triazolo(1,5-c)pyrimidin-2-yl)-6-(trifluoromethyl)benzenesulfonamide

Other status information

Possible groundwater contaminant

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Herbicide Resistance Class (WSSA MoA class)

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Echinochloa crus-galli

Physical state

Off-white to pale pink solid (depending on purity) with a musty odour

Formulations

Property

Value

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

Dow AgroSciences

Example products using this active

Penoxsulam DE638
Galleon
Granite
Grasp Xtra
Sapphire
Viper
Boa

Formulation and application details

Used as a broadcast spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

408

at 19 °C

Moderate

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

20300

Acetone

1480

Methanol

n-Octanol

15300

Acetonitrile

Melting point (°C)

212

Boiling point (°C)

Decomposes before melting

Degradation point (°C)

214

Flashpoint (°C)

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

2.50 X 10^-01

Calculated

Log P

-0.602

at 19 °C

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Animal studies

Density (g ml⁻¹)

1.61

Dissociation constant pKa) at 25 °C

5.1

Weak acid

Vapour pressure at 20 °C (mPa)

2.49 X 10^-11

Low volatility

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

2.95 X 10^-14

Non-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: 284nm = 9530
Acidic solution: 251nm = 7450, 284nm = 9520
Basic solution: 228nm = 44300, 284nm = 9380

Surface tension (mN m⁻¹)

67.5

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

21.9

Non-persistent

DT₅₀ (lab at 20 °C)

21.9

Non-persistent

DT₅₀ (field)

6.6

Non-persistent

DT₉₀ (lab at 20 °C)

153

Persistent

DT₉₀ (field)

36.7

DT₅₀ modelling endpoint

Note

EU 2024 dossier lab studies DT₅₀ (normalised) range 10.4-90.9 days, DT₉₀ (measured) range 45.1-631 day; Field studies DT₅₀ (measured) range 2.4-10.8 days, DT₉₀ (measured) range 17.5-55.9 days, Soils=2; Literature lab values DT₅₀ range 4.8-10.6 days (anaerobic, global), 22-118 days (aerobic global), 6.6 days (anaerobic EU), 22-58 days (aerobic, EU)

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

2.8

Note

Published literature RL₅₀ range 1.1-4.4 days, 2 field crops, various matrices, n=2

Aqueous photolysis DT₅₀ (days) at pH 7

Value

0.5

Fast

Note

Main degradation route in water

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

Value

Stable

Note

Stable under all normal environmental conditions

Water-sediment DT₅₀ (days)

30.5

Moderately fast

Water phase only DT₅₀ (days)

27.2

Slow

Sediment phase only DT₅₀ (days)

34.9

Stable

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)

0.88

Moderately mobile

K_oc (mL g⁻¹)

76.8

Notes and range

EU dossier 2024 K_d range 0.2-2.5 mL g⁻¹, K_oc range 12.5-253 mL g⁻¹, Soils=10; Literature K_oc 12-1141 mL g⁻¹ (global), 12-305 mL g⁻¹ (EU)

Freundlich

K_f (mL g⁻¹)

0.65

Mobile

K_foc (mL g⁻¹)

37.2

¹/_n

0.89

Notes and range

EU dossier 2024 K_f range 0.129-1.96, K_foc range 7.8-198.2 mL g⁻¹, ¹/_n range 0.83-1.01, Soils=10

pH sensitivity

Sorption increases with decreasing pH

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.99

Calculated

Transition state

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

Value

1.01 X 10^-02

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

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

2.1

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)

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

2-(2,2-difluoroethyoxy)-6-(trifluoromethyl)benzenesulfonamide

Minor fraction

0.330

2-(2,2-difluoroethoxy)-N-(5-hydroxy-8-methoxy(1,2,4)triazolo(1,5-c)pyrimidin-2-yl)-6-(trifluoromethyl)benzenesulfonamide

Major fraction

0.592

3-(((2-(2,2-difluoroethoxy)-6-(trifluoromethyl)phenyl)sulfonyl)amino)-1H-1,2,4-triazole-5-carboxylic acid (Ref: X768359)

Major fraction

0.483

2-{[2,2-dilfuoroethoxy)-6-(trifluoromethyl)phenyl]sulphonyl}-amino-1H-1,2,4-triazole (Ref: BST)

Minor fraction

0.006

2-(2,2-difluoroethoxy)-N-(iminomethyl)-6-(trifluoromethyl)-benzenesulfonamide (Ref: X776129; SFA)

Major fraction

0106

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)

2-(2,2-difluoroethyoxy)-6-(trifluoromethyl)benzenesulfonamide

Relevancy unknown

2-(2,2-difluoroethoxy)-N-(iminomethyl)-6-(trifluoromethyl)-benzenesulfonamide (Ref: X776129; SFA)

Relevancy unknown

3-(((2-(2,2-difluoroethoxy)-6-(trifluoromethyl)phenyl)sulfonyl)amino)-1H-1,2,4-triazole-5-carboxylic acid (Ref: X768359)

Relevancy unknown

2-{[2,2-dilfuoroethoxy)-6-(trifluoromethyl)phenyl]sulphonyl}-amino-1H-1,2,4-triazole (Ref: BST)

Relevancy unknown

triethylamine salt of 2-(2,2-difluoroethoxy-6-trifluoromethylbenzene)sulfonic acid (Ref: BSA; X1252787)

Relevancy unknown

5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amine (Ref: 2-amino-TP)

Relevancy unknown

2-(2,2-difluoroethoxy)-N-(5-hydroxy-8-methoxy(1,2,4)triazolo(1,5-c)pyrimidin-2-yl)-6-(trifluoromethyl)benzenesulfonamide

Relevancy unknown

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

(5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)sulfamic acid
Note: EFSA 2024

TPSA

Surface water; Sediment

A5
Note: EFSA 2024

2-amino-TP

Surface water; Sediment

2-(2,2-difluoroethoxy)-N-(5-hydroxy-8-methoxy(1,2,4)triazolo(1,5-c)pyrimidin-2-yl)-6-(trifluoromethyl)benzenesulfonamide
Note: EFSA 2024

8-OH-XDE-638

Surface water; Sediment; Plant; Animal

3-(((2-(2,2-difluoroethoxy)-6-(trifluoromethyl)phenyl)sulfonyl)amino)-1H-1,2,4-triazole-5-carboxylic acid (Ref: X768359)
Note: EFSA 2024

X768359; BSTCA

Surface water; Sediment; Plant

2-{[2,2-dilfuoroethoxy)-6-(trifluoromethyl)phenyl]sulphonyl}-amino-1H-1,2,4-triazole
Note: EFSA 2024

BST

Surface water; Sediment; Plant

2-(2,2-difluoroethyoxy)-6-(trifluoromethyl)benzenesulfonamide
Note: EFSA 2024

X768360; Sulfonamide

Surface water; Sediment

2-(2,2-difluoroethoxy)-N-(iminomethyl)-6-(trifluoromethyl)-benzenesulfonamide
Note: EFSA 2024

X776129; SFA

Surface water; Sediment

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

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)

> 2000

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 1000 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)

> 1000

Eisenia foetida

Low

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

> 115.5

Eisenia foetida EC20 Viper at 20 g l⁻¹ a.s.

Low

Soil micro-organisms

Nitrogen transformation: No significant adverse effect

Dose 0.67 mg kg⁻¹ soil Day 42

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

6.2

Sugarbeet
Seedling emergence, EC₅₀
as g ha⁻¹

6.2

Soybean
Vegetative vigour, EC₅₀
as g ha⁻¹

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)

> 100

Apis mellifera

Low

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

Chronic 10 d-LDD₅₀

5.62

Apis mellifera

Notes

Bumblebees (Bombus spp.)

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

> 200

Bombus terrestris

Low

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

> 72.6

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

> 40

Chrysoperla carnea

Beneficial insects (Parasitic wasps)

14.3% Mortality LR₅₀ g ha⁻¹ 48 hr

Aphidius rhopalosiphi

Beneficial insects (Predatory mites)

>50% Mortality at dose 40 g ha⁻¹

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)

> 100

Oncorhynchus mykiss

Low

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

10.2

Pimephales promelas

Low

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

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

> 100

Daphnia magna

Low

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

2.95

Daphnia magna

Moderate

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

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

114

Americamysis bahia

Low

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

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

61.0

Chironomus riparius

Low

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

810

Chironomus riparius

Low

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

0.002

Lemna gibba

High

Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)

0.0034

Myriophyllum spicatum

High

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

> 0.233

Anabaena flos-aquae

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)

> 5000

Rat

Low

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

5000

Rabbit

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 3.5

Rat

Other Mammal toxicity endpoints

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

0.016

Rat SF=300

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

Not allocated

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

Not allocated

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

0.15

Dog SF=100

Dermal penetration studies (%)

0.29-8.4

Concentration dependent

Dangerous Substances Directive 76/464

List II

Exposure Routes

Public

Acceptable for proposed uses

Occupational

Acceptable for proposed uses

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Rapid and extensive mainly via urine in females and faeces in males

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

Possible blood, liver and kidney toxicant
US EPA - weak evidence to suggest possible human carcinogen

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Environment: H400, H410

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

penoxsulam

French

penoxsulame

German

Penoxsulam

Danish

penoxsulam

Italian

penoxsulam

Spanish

penoxsulam

Greek

Polish

penoksulam

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	26/05/2025
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