Mepronil (Ref: B1 2459)	Last updated: 18/02/2021
(Not known by any other names)

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GENERAL INFORMATION

Description	A systemic fungicide used to control diseases caused by Basidomycetes
Example pests controlled	Rhizoctonia spp.; Puccinia spp.; Sheath blight; Root rot; Rust; Damping off
Example applications	Rice; Potatoes; Cotton; Top fruit
Efficacy & activity	-
Availability status	Obsolete
Introduction & key dates	1981

UK regulatory status

UK COPR regulatory status	Not approved
Date COPR inclusion expires	Expired
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	-
Date EC 1107/2009 inclusion expires	Expired
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

Also used in

Also used in	-

Chemical structure

Isomerism	None
Chemical formula	C₁₇H₁₉NO₂
Canonical SMILES	CC1=CC=CC=C1C(=O)NC2=CC(=CC=C2)OC(C)C
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	BCTQJXQXJVLSIG-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C17H19NO2/c1-12(2)20-15-9-6-8-14(11-15)18-17(19)16-10-5-4-7-13(16)3/h4-12H,1-3H3,(H,18,19)
2D structure diagram/image available?	Yes

General status

Pesticide type	Fungicide
Substance group	Benzanilide
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Systemic with protective and curative action. Succinate DeHydrogenase Inhibitor.
CAS RN	55814-41-0
EC number	-
CIPAC number	533
US EPA chemical code	-
PubChem CID	41632
Molecular mass	269.33
PIN (Preferred Identification Name)	-
IUPAC name	3'-isopropoxy-o-toluanilide
CAS name	2-methyl-N-(3-(1-methylethoxy)phenyl)benzamide
Other status information	-
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	Not applicable
Herbicide Resistance Classification (WSSA)	Not applicable
Insecticide Resistance Classification (IRAC)	Not applicable
Fungicide Resistance Classification (FRAC)	7
Examples of recorded resistance	-
Physical state	Colourless crystals

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	-
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)		12.7	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)		500000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Acetone	-
		380000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Methanol	-
		1370	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source n-Hexane	-
		160000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Toluene	-
Melting point (°C)		91.4	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Boiling point (°C)		-	-	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		225	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Octanol-water partition coefficient at pH 7, 20 °C	P	4.57 X 1003	Calculated	-
	Log P	3.66	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	High
Bulk density (g ml⁻¹)		1.11	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		0.056	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		1.19 X 10-03	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Non-volatile
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)	50	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Moderately persistent
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	Best available data
Dissipation rate RL₅₀ on plant matrix	Value	-	-	-
	Note	-
Dissipation rate RL₅₀ on and in plant matrix	Value	2.3	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source	-
	Note	Rice leaves, n=1
Aqueous photolysis DT₅₀ (days) at pH 7	Value	6.6	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Moderately fast
	Note	DT₅₀: 6.6 days in natural waters, 4.5 days in pure water
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7	Value	Stable	W4 W = French database provided by ARVALIS-Institut du Végétal 4 = Verified data	Stable
	Note	pH sensitive: DT₅₀ 261 days at pH 4, 276 days at pH 7, 253 days at pH 9, all at 25 °C (L3)
Water-sediment DT₅₀ (days)		-	-	-
Water phase only DT₅₀ (days)		-	-	-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd	-	P3 P = Other governments and regulators 3 = Unverified data of known source	Slightly mobile
	Koc	974
	Notes and range	Best available data
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		1.72	Calculated	Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate	Value	5.34 X 10-02	Calculated	-
	Note	-
Potential for particle bound transport index		Medium	Calculated	-
Potential for loss via drain flow		Slightly mobile	Calculated	-

ECOTOXICOLOGY

Property		Value	Source; quality score; and other information	Interpretation
Bio-concentration factor	BCF (l kg⁻¹)	268	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source Estimated	Threshold for concern
	CT₅₀ (days)	Not available		-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		> 10000	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)	5.9	L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source Rat 2 year	High
	(ppm diet)	-		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		> 8000	L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source Gallus gallus	Low
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		> 10	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Oncorhynchus mykiss	Moderate
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		> 5.0	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Daphnia magna	Moderate
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)	> 100	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low
	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)		> 10000	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)		10000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		1.32	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	-
Other Mammal toxicity endpoints		-	-	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		0.05	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
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 A3 A = Chromosome aberration (EFSA database) 3 = Negative ; 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 XNo, known not to cause a problem No data found Respiratory tract irritant Skin irritant Skin sensitiser No data found No data found No data found Eye irritant Phototoxicant   No data found No data found
General human health issues		No further information available

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	Health: H378 Environment: H400, H410
EC Risk Classification	Not classified: Obsolete
EC Safety Classification	Not classified: Obsolete
WHO Classification	U (Unlikely to present an acute hazard)
UN Number	-
Waste disposal & packaging	-

TRANSLATIONS

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

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Record last updated:	18/02/2021
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