Pyrazolynate	Last updated: 03/03/2021
(Also known as: pyrazolate)

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GENERAL INFORMATION

Description	An obsolete herbicide that was used to control weeds in paddy fields
Example pests controlled	Broad-leaved weeds including arrowhead (sagittaria trifolium) and water plantain (Alisma canalicatum); Grassy weeds; Sedges
Example applications	Paddy rice
Efficacy & activity	-
Availability status	Obsolete
Introduction & key dates	-

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	No
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

Also used in	Japan

Chemical structure

Isomerism	-
Chemical formula	C₁₉H₁₆Cl₂N₂O₄S
Canonical SMILES	CC1=CC=C(C=C1)S(=O)(=O)OC2=C(C(=NN2C)C)C(=O)C3=C(C=C(C=C3)Cl)Cl
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	ASRAWSBMDXVNLX-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C19H16Cl2N2O4S/c1-11-4-7-14(8-5-11)28(25,26)27-19-17(12(2)22-23(19)3)18(24)15-9-6-13(20)10-16(15)21/h4-10H,1-3H3
2D structure diagram/image available?	Yes

General status

Pesticide type	Herbicide
Substance group	Benzoylpyrazole
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Bleaching: Inhibition of 4-HPPD
CAS RN	58011-68-0
EC number	-
CIPAC number	-
US EPA chemical code	-
PubChem CID	42619
Molecular mass	439.31
PIN (Preferred Identification Name)	4-(2,4-dichlorobenzoyl)-1,3-dimethyl-1H-pyrazol-5-yl 4-methylbenzene-1-sulfonate
IUPAC name	4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol-5-yl toluene-4-sulfonate
CAS name	(2,4-dichlorophenyl)[1,3-dimethyl-5-[[(4-methylphenyl)sulfonyl]oxy]-1H-pyrazol-4-yl]methanone
Other status information	-
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	F2
Herbicide Resistance Classification (WSSA)	27
Insecticide Resistance Classification (IRAC)	Not applicable
Fungicide Resistance Classification (FRAC)	Not applicable
Examples of recorded resistance	-
Physical state	Colourless crystalline solid

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Kusahope Kusakarn
Example products using this active	-
Formulation and application details	-

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		0.055	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)		1400	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Ethanol	-
		11800	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Ethyl acetate	-
		600	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Hexane	-
Melting point (°C)		118	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Boiling point (°C)		-	-	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	3.80 X 1002	Calculated	-
	Log P	2.58	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Low
Bulk density (g ml⁻¹)		1.47	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		1.3 X 10-02	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	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)	9	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Non-persistent
	DT₅₀ (lab at 20 °C)	9	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Non-persistent
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	Literature gives DT₅₀ as 8-10 days general soils (Q3), <1.0 day in paddy water and 2.2 days in paddy soil (R3)
Dissipation rate RL₅₀ on plant matrix	Value	-	-	-
	Note	-
Dissipation rate RL₅₀ on and in plant matrix	Value	-	-	-
	Note	-
Aqueous photolysis DT₅₀ (days) at pH 7	Value	-	-	-
	Note	-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7	Value	-	-	-
	Note	-
Water-sediment DT₅₀ (days)		-	-	-
Water phase only DT₅₀ (days)		-	-	-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd	-	-	-
	Koc	-
	Notes and range	-
Freundlich	Kf	-	-	-
	Kfoc	-
	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)	-	-	-
	CT₅₀ (days)	-		-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		9550	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source 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)		-	-	-
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		92.0	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Cyprinus carpio	Moderate
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		-	-	-
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)		-	-	-
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	-	-	-
	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)		9550	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		5000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		2.5	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source Rat	-
Other Mammal toxicity endpoints		Intraperitoneal LD₅₀ = 9550 mg kg⁻¹	V3 V = ChemID online databases / IPCS INCHEM (ChemID; IPCS INCHEM ) 3 = Unverified data of known source Rat	-
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		-	-	-
Exposure Routes	Public	-
	Occupational	-
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 A0 A = Chromosome aberration (EFSA database) 0 = No data ; B0 B = DNA damage/repair (EFSA database) 0 = No data ; C0 C = Gene mutation (EFSA database) 0 = No data ; D0 D = Genome mutation (EFSA database) 0 = No data ; E0 E = Unspecified genotoxicity type (miscellaneous data source) 0 = No data No data found Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant No data found No data found No data found Respiratory tract irritant Skin irritant Skin sensitiser No data found XNo, known not to cause a problem No data found Eye irritant Phototoxicant   No data found No data found
General human health issues		Slightly hazardous if ingested

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	-
EC Risk Classification	Not classified: Obsolete
EC Safety Classification	Not classified: Obsolete
WHO Classification	Not classified: Obsolete
UN Number	-
Waste disposal & packaging	-

TRANSLATIONS

Language	Name
English	pyrazolynate
French	pyrazolynate
German	-
Danish	-
Italian	-
Spanish	-
Greek	-
Polish	-
Swedish	-
Hungarian	-
Dutch	-

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Record last updated:	03/03/2021
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