Bispyribac-sodium (Ref: KIH-2023)

Bispyribac-sodium (Ref: KIH-2023)	Last updated: 15/03/2024
(Also known as: KUH 911; V 10029)

SUMMARY

Bispyribac-sodium is a post-emergence herbicide used in aquatic situations, turf and sports grounds amongst other situations. It is highly soluble in water, non-volatile and is not expected to be persistent in soil systrs but may be, depending on conditions in water. Based on its physico-chemical properties bispyribac-sodium is not expected to leach to groundwater. Its toxicity to biodiversity is generally low to moderate. It has a low mammalian oral toxicity and may be a skin sensitizer.

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: Moderately mobile	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate	Human health Low alert

GENERAL INFORMATION

Description

A post-emergence herbicide for the control of grasses, sedges and broad-leaved weeds in paddy rice and other crops/situations

Example pests controlled

Alligatorweed, Duckweed, Mosquito ferm, Water fern, Water hyacinth, Water pennywort, Parrot feather; Annual bluegrass; Creeping bent grass

Example applications

Aquatic sitiuations such as drainage ditches, lakes, marshes; Golf courses, turf grass & sod farms

Efficacy & activity

Availability status

Current

Introduction & key dates

1998, discovered; 1997, first introduced

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/07/2026

UK LERAP status

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Italy/Portugal

Date EC 1107/2009 inclusion expires

Not applicable

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

A racemate comprising equimolar amounts of (R)- and (S)-binapacry sodium

Chemical formula

C₁₉H₁₇N₄NaO₈

Canonical SMILES

COC1=CC(=NC(=N1)OC2=C(C(=CC=C2)OC3=NC(=CC(=N3)OC)OC)C(=O)[O-])OC.[Na+]

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

FUHMZYWBSHTEDZ-UHFFFAOYSA-M

International Chemical Identifier (InChI)

InChI=1S/C19H18N4O8.Na/c1-26-12-8-13(27-2)21-18(20-12)30-10-6-5-7-11(16(10)17(24)25)31-19-22-14(28-3)9-15(23-19)29-4;/h5-9H,1-4H3,(H,24,25);/q;+1/p-1/fC19H17N4O8.Na/q-1;m

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Pyrimidinyl carboxy compound; Benzoic acid herbicide

Minimum active substance purity

930 g kg⁻¹

Known relevant impurities

EU dossier - none identified

Substance origin

Synthetic

Mode of action

Selective, systemic action absorbed by foliage and roots.Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS.

CAS RN

125401-92-5

EC number

No data found

CIPAC number

748.011

US EPA chemical code

078906

PubChem CID

23682789

CLP index number

No data found

Molecular mass

452.36

PIN (Preferred Identification Name)

sodium 2,6-bis[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoate

IUPAC name

sodium 2,6-bis(4,6-dimethoxypyrimidin-2-yloxy)benzoate

CAS name

sodium 2,6-bis((4,6-dimethoxy-2-pyrimidinyl)oxy)benzoate

Other status information

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

Resistance to ALS-inhibitors is locally present in sub-populations of Alisma plantago-aquatica and Schoenoplectus mucronatus in Southern European rice growing areas

Physical state

White powder

Related substances & organisms

bispyribac

pyriflubenzoxim

Formulations

Property

Value

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

Kumiai Chemical Industry
BOC Sciences

Example products using this active

Adora 400 SC
Nominee 400 SC
Tradewind

Formulation and application details

Usually supplied as a suspension concentrate that is 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)

64000

High

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

25000

Methanol

0.061

Ethyl acetate

0.0083

n-Hexane

1.4

Acetone

Melting point (°C)

223

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

223

Flashpoint (°C)

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

9.33 X 10^-02

Calculated

Log P

-1.03

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

1.47

Dissociation constant pKa) at 25 °C

3.35

Weak acid

Vapour pressure at 20 °C (mPa)

5.50 X 10^-06

Low volatility

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

3.12 X 10^-11

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Maxima is below 290nm

Surface tension (mN m⁻¹)

69.79

at 20°C

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)

12.8

Non-persistent

DT₅₀ (field)

6.3

Non-persistent

DT₉₀ (lab at 20 °C)

42.6

Moderately persistent

DT₉₀ (field)

20.7

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 6-19.6 days (soil) & 19.2 days (paddy field soil), DT₉₀ range 19.9-65.3 days (soil) & 62.7-64.7 days (paddy field soil); Field studies DT₅₀ range 2.1-7.6 days (Southern Europe), DT₉₀ range 6.9-30.2 days

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Stable

Note

DT₅₀: 42 days in natural waters, 500 days in pure water

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

Value

Stable

Note

Stable pH 7 to pH 9; DT₅₀: 18.7 days pH 4, 20 °C

Water-sediment DT₅₀ (days)

35.3

Moderately fast

Water phase only DT₅₀ (days)

32.1

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.

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

K_oc

Notes and range

Freundlich

K_f

1.16

Moderately mobile

K_foc

302

¹/_n

0.958

Notes and range

EU dossier K_f range 0.60-2.01 mL g⁻¹, K_foc range 143-604 mL g⁻¹, ¹/_n range 0.935-0.990, Soils=5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.21

Calculated

Low leachability

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

Value

6.53 X 10^-03

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

0.8

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

2-(4,6-dimethoxypyrimidin-2-yl)oxy-6-hydroxy benzoic acid

Minor fraction

2-hydroxy-4-6-dimethoxypyrimidine

Minor fraction

benzoic acid, 2-((4,6-dimethoxy-2-pyrimidinyl)oxy)6-hydroxy, sodium salt

Major fraction

0.15

benzoic acid, 2-(4,6-dimethoxy-2-pyrimidinyl)oxy)-6-((4-hydroxy-6-methoxy-2-pyrimidinyl)oxy), sodium salt (Ref: KIB 8651)

Major fraction

0.144

2,4-dihydroxy-6-methoxypyrimidine

Minor fraction

0.058

sodium 2-hydroxy-6-(4-hydroxy-6-methoxypyrimidin-2-yl)oxybenzoate

Minor fraction

Paddy soil

2-hydoxy-6-[(4-hydroxy-6-methoxypyrimidin-2-yl)oxy]benzoic acid

Minor fraction

also formed in paddy soil

2-(4,6-dimethoxypyrimidin-2-yl)oxy-6-(4-hydroxy-6-methoxypyrimidin-2-yl)oxybenzenzoic acid

Minor fraction

also formed in paddy soil

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)

2,4-dihydroxy-6-methoxypyrimidine

Relevancy unknown

sodium 2-hydroxy-6-(4-hydroxy-6-methoxypyrimidin-2-yl)oxybenzoate

Relevancy unknown

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

2-(4,6-dimethoxy-5-hydroxypyrimidin-2-yl)oxy-6-(4,6-dimethoxypyrimidin-2-yl)oxybenzoic acid

5-OH-5750; KIH-2023-M8

Animal; Plant; Rat

benzoic acid, 2-((4,6-dimethoxy-2-pyrimidinyl)oxy)6-hydroxy, sodium salt

desMe-2023

Surface water

2,4-dihydroxy-6-methoxypyrimidine

MeBA

Surface water

sodium 2-hydroxy-6-(4-hydroxy-6-methoxypyrimidin-2-yl)oxybenzoate

Na-DesMe-180; KIH-2023-M10; M9-Na

Plant

sodium 2-(4,6-dimethoxy-5-hydroxypyrimidin-2-yl)oxy-6-(4,6-dimethoxypyrimidin-2-yl)oxybenzoate

5-OH-2023; M8-Na

Plant

benzoic acid, 2,6-bis[(4,6-dimethoxypyrimidin-2-yl)oxy]

KIA-5750; M12433

2,6-dihydroxybenzoic acid

2,6-DBA

Animal

9-(4,6-dimethoxypyrimidin-2-yl)oxy-3-methoxy-1H, 10H-pyrimido[2,1-b]-[1,3]benzoxazine-1,10 dione

Cyc-DesMe-2023

methyl 1-O--[2,6-bis[(4,6-dimethoxypyrimidin-2-yl)oxy]-benzoyl-beta-D-glucuronate

Me-glucuro-2023

Rat

2-hydoxy-6-[(4-hydroxy-6-methoxypyrimidin-2-yl)oxy]benzoic acid
Note: CAS no: 172838-16-3

DesMe-180; KIH-2023-M9; FHW0122B;M18537

Animal; Plant

2-(4,6-dimethoxypyrimidin-2-yl)oxy-6-hydroxy benzoic acid

BX-180; KIH-2023-M2; PHU120

Animal; Rat; Plan

2-hydroxy-4-6-dimethoxypyrimidine

Me2BA; KIH-2023-M3; M15876; PHU1305

Animal; Rat; Plant

2,4,6-trimethoxypyrimidine

Me3BA; FHW0112A; KIH-2023-M7

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

2635

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

1.1

Rat

High

(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)

> 2081 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)

> 957

Eisenia foetida

Moderate

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

Soil micro-organisms

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

Dose: 5x field rate

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Honeybees (Apis spp.)

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

> 200

Apis mellifera

Low

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

> 140.67

Apis mellifera

Low

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)

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) as % Mortality at dose 0.3 g ha⁻¹

2.1

Coccinella septempunctata Adult corr

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps) as % Mortality at dose 0.3 g ha⁻¹

12.2

Aphidius rhopalosiphi Adult corr

Beneficial insects (Predatory mites) as % Mortality at dose 0.3 g ha⁻¹

1.0

Typhlodromus pyri Adult corr

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)

> 95

Oncorhynchus mykiss

Moderate

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

Pimephales promelas 32 day

Moderate

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

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

> 95

Daphnia magna

Moderate

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

110

Daphnia magna

Low

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (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)

105

Chironomus riparius

Low

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

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

0.0127

Lemna gibba

Moderate

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

3.2

Raphidocelis subcapitata

Moderate

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)

2635

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

4.48

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)

None allocated

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

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

0.072

Rat SF=100

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Risks acceptable for proposed uses

Occupational

Risks 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)

0.03

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

Possible liver toxicant

Handling issues

Property

Value and interpretation

General

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

CLP classification 2013

Health: H317, H319
Environment: H411

WHO Classification

III (Slightly hazardous)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

Limited shelf-life. Store 0-6 DegC

TRANSLATIONS

Language

Name

English

bispyribac-sodium

French

bispyribac sodium

German

Bispyribac-Natrium

Danish

bispyribac-natrium

Italian

bispyribac-sodium

Spanish

bispiribac-sodio

Greek

Polish

bispirybak sodowy

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	15/03/2024
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