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isoxaben (Ref: EAF 496)
** benzamizole ** benzamidazole ** EL 107 ** Translations

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GENERAL INFORMATION Click here for an explantaion of the general chemical status information
for isoxaben

Description: A broad-spectrum pre-emergence soil-acting amide herbicide for use mainly with grass and fruit to control broad-leaved weeds

Example pests controlled: Broad-leaved weeds including marestail, hairy fleabane, mallow, Shepherd's purse, henbit, checkweed, sowthistle

Example applications: Tree-nut plantations; Orchards; Vinyards; Ornamental trees and shrubs; Winter cereals

Efficacy & activity: -

Availability status: Current

Introduction & key dates: 1984, France

EC Regulation 1107/2009 (repealing 91/414):
Status Approved
Dossier rapporteur/co-rapporteur Austria/Finland
Date inclusion expires 31/05/2021
EU Candidate for substitution (CfS) No
Listed in EU database Yes

Approved for use () or known to be used () in the following European countries: Click to access a note on the approvals information on this site

AT

BE

BG

CY

CZ

DE

DK

EE

EL

ES

FI

FR

HR

HU

IE

IT

LT

LU

LV

MT

NL

PL

PT

RO

SE

SI

SK

UK

Also used in: Australia

Chemical structure: Click here for further information on the general chemical status information used on this site
Isomerism Isomeric with the isomers typically comprising around 2% of the product
Chemical formula C18H24N2O4
Canonical SMILES CCC(C)(CC)C1=NOC(=C1)NC(=O)C2=C(C=CC=C2OC)OC
Isomeric SMILES No data
International Chemical Identifier key (InChIKey) PMHURSZHKKJGBM-UHFFFAOYSA-N
International Chemical Identifier (InChI) InChI=1S/C18H24N2O4/c1-6-18(3,7-2)14-11-15(24-20-14)19-17(21)16-12(22-4)9-8-10-13(16)23-5/h8-11H,6-7H2,1-5H3,(H,19,21)
Structure diagram/image available? Yes

General status: Click here for further information on the general chemical status information used on this site
Pesticide type Herbicide
Substance group Benzamide
Minimum active substance purity 910 g/kg
Known relevant impurities EU dossier - toluene 3g/kg
Substance origin Synthetic
Mode of action Selective, disrupts root and stem development in germinating seeds. Inhibition of cell wall synthesis.
CAS RN 82558-50-7
EC number 407-190-8
CIPAC number 701
US EPA chemical code 125851
PubChem CID 73672
Molecular mass (g mol-1) 332.39
PIN (Preferred Identification Name) -
IUPAC name N-[3-(1-ethyl-1-methylpropyl)-1,2-oxazol-5-yl]-2,6-dimethoxybenzamide
CAS name N-(3-(1-ethyl-1-methylpropyl)-5-isoxazolyl)-2,6-dimethoxybenzamide
Other status information -
Relevant Environmental Water Quality Standards -
Herbicide Resistance Classification (HRAC) L
Herbicide Resistance Classification (WSSA) 21
Insecticide Resistance Classification (IRAC) Not applicable
Fungicide Resistance Classification (FRAC) Not known
Examples of recorded resistance -
Physical state Colourless crystalline solid or waxy powder
Related substances & organisms

Formulations:
Property Click here for information on the general product and branding information used on this site Value
Example manufacturers & suppliers of products using this active now or historically
  • AgriGuard
  • Dow AgroSciences
  • Landseer
  • Syngenta
  • Elanco
Example products using this active
  • Fargro Axit
  • Skirmish
  • Flexidor 125
  • EAF-496
UK LERAP status None
Formulation and application details Often supplied as a suspension concentrate.


ENVIRONMENTAL FATE

for isoxaben

Property Click here for information on the parameters used to describe environmental fate on this site Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with fate data Interpretation Click here for information on the way in which we interpret environmental fate data
Solubility - In water at 20oC (mg l-1) 0.93 A5 Low
Solubility - In organic solvents at 20oC (mg l-1) 88000 A5 - Ethyl acetate -
270000 A5 - Acetone -
98000 A5 - Methanol -
4000 A5 - Xylene -
Melting point (oC) 175.3 A5 -
Boiling point (oC) Decomposes before boiling A5 -
Degradation point (oC) 200 A4 -
Flashpoint (oC) Not expected to self ignite; Not highly flammable A5 -
Octanol-water partition coefficient at pH 7, 20oC P 8.71 X 1003 Calculated -
Log P 3.94 L3 High
Bulk density (g ml-1)/Specific gravity 0.58 L3 -
Dissociation constant (pKa) at 25oC 9.78 A5 -
Note: Weak acid
Vapour pressure at 20oC (mPa) 5.50 X 10-04 A5 Low volatility
Henry's law constant at 25oC (Pa m3 mol-1) 1.96 X 10-04 A5 Non-volatile
GUS leaching potential index Click here for a note on the limitations of the GUS index 3.60 Calculated High leachability
SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate Click here for a note on the limitations of the SCI-GROW index Value 7.72 X 10-01 Calculated -
Note -
Potential for particle bound transport index Click here for a note on the limitations of the potential for particle bound transport index - Calculated Medium
Maximum UV-vis absorption L mol-1 cm-1 Neutral solution: 252nm = 16500; [Acidic solution: 252nm = 16500; [Basic solution, 215nm = 11400, 275nm = 20800 A5 -
Surface tension (mN m-1) 72.9 +/- 0.18 A5 at 19oC -

Degradation:
Property Click here for information on the parameters used to describe substance degradation Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with degradation data Interpretation Click here for information on the way in which we interpret substance degradation data
General biodegradability -
Soil degradation (days) (aerobic) DT50 (typical) 105 L3 Persistent
DT50 (lab at 20oC) 301 A5 Persistent
DT50 (field) 123 A5 Persistent
DT90 (lab at 20oC) 1000 A5 -
DT90 (field) 407 A5 -
DT50 modelling endpoint - - -
Note EU dossier lab studies DT50 range 127-891 days, DT90 range 421-2952 days; field studies DT50 range 66-309 days, DT90 range 219-1028 dats
Dissipation rate RL50 on plant matrix Value 6.7 R4 -
Note Published literature RL50 range 5.0-8.4 days, 2 field crops, various matrices, n=2
Dissipation rate RL50 on and in plant matrix Value 3.8 R3 -
Note Turf grass blades, n=1
Aqueous photolysis DT50 (days) at pH 7 Value 6 A5 Moderately fast
Note -
Aqueous hydrolysis DT50 (days) at 20oC and pH 7 Value Stable A5 -
Note Stable pH 5 to pH 9
Water-sediment DT50 (days) 16.8 A5 Fast
Water phase only DT50 (days) 8.8 A5 Moderately fast

Soil adsorption and mobility:
Property Click here for information on the parameters used to describe substance adsorption and mobility Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with adsorption and mobility data Interpretation Click here for information on the way in which we interpret substance adsorption and mobility
Linear Kd 8.7 A5 Slightly mobile
Koc 909
Notes and range EU dossier Kd range 6.43-12.6 mL/g, Koc range 700-1290 mL/g, Soils=4
Freundlich Kf 3.3 A5 Moderately mobile
Kfoc 354
1/n 0.905
Notes and range EU dossier Kf range 0.81-6.63 mL/g, Kfoc range 190-570 mL/g, 1/n range 0.892-0.911, Soils=5
pH sensitivity No

Key metabolites:
Metabolite Formation medium Estimated maximum occurrence fraction 1107/2009 relevancy Click here for further information on 1107/2009 relevancy
N-(3-(1-hydroxy-1-methyl-propyl)-5-isoxazolyl)-2,6,dimethoxybenzamide This metabolite may cause environmental pollution, click here for further information Soil   0.108   Major fraction, Relevancy unknown
N-(3-(1-ethyl-1-methyl-2-oxypropyl)isoxazol-5-yl)-2,6-dimethoxybenzamide Soil   0.073   Minor fraction, Relevancy unknown
N-(3-amino-4-ethyl-4-methyl-2-hexenoyl)-2,6-dimethoxybenzamide This metabolite may cause environmental pollution, click here for further information Soil   0.60   Major fraction; Relevant
2,6-dimethoxybenzamide This metabolite may cause environmental pollution, click here for further information Soil   0.129   Major fraction; Relevant

Other known metabolites:
Metabolite name and reference Aliases Formation medium / Rate Estimated maximum occurrence fraction Metabolising enzymes
6-(1-ethyl-1-methylpropyl)-2-(2-hydroxy-6-methoxyphenyl)-4-pyrimidinol
Note: DT50 soil 47 days
methoxyphenyl pyrimidinol Soil (Anaerobic) 0.331 -
2-hydroxy-6-methoxybenzamide hydroxymethoxy benzamide Water - -


ECOTOXICOLOGY

for isoxaben

Property Click here for information on the parameters used to describe substance ecotoxicology Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with ecotoxicology data Interpretation Click here for information on the way in which we interpret substance ecotoxicology
Bio-concentration factor BCF (l kg-1) 70.5 A5 Whole fish Low potential
CT50 (days) 0.49 -
Mammals - Acute oral LD50 (mg kg-1) > 10000 A5 Rat Low
Mammals - Short term dietary NOEL (mg kg-1) 5.6 L2 Rat, 2 year High
(ppm diet) - -
Birds - Acute LD50 (mg kg-1) > 2000 A5 Colinus virginianus Low
Birds - Short term dietary (LC50/LD50) > 937 mg kg bw-1 day-1 A5 Colinus virginianus -
Fish - Acute 96 hour LC50 (mg l-1) > 0.87 A5 Cyprinodon variegatus Moderate
Fish - Chronic 21 day NOEC (mg l-1) 0.87 Q2 Oncorhynchus mykiss Moderate
Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) > 1.3 A5 Daphnia magna Moderate
Aquatic invertebrates - Chronic 21 day NOEC (mg l-1) 0.69 A5 Daphnia magna Moderate
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) 8.0 A5 Chironomus riparius, development Moderate
Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg-1) - - -
Aquatic plants - Acute 7 day EC50, biomass (mg l-1) 0.011 A5 Lemna gibba Moderate
Non-target plants 20 A5 Cocklebur
Seedling emergence, ER50
as g/ha
-
625 - -
Algae - Acute 72 hour EC50, growth (mg l-1) > 1.4 A5 Raphidocelis subcapitata Moderate
Algae - Chronic 96 hour NOEC, growth (mg l-1) > 1.4 A5 Selenastrum capricornutum Low
Honeybees Contact acute 48 hour LD50 (μg bee-1) > 100 A5 Low
Oral acute 48 hour LD50 (μg bee-1) > 100 A5 Low
Unknown mode acute 48 hour LD50 (μg bee-1) - - -
Earthworms - Acute 14 day LC50 (mg kg-1) > 500 A5 Eisenia foetida, corr Moderate
Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1) 3.34 A5 Eisenia foetida, corr Moderate
Other soil macro-organisms - e.g. Collembola LR50 / EC50 / NOEC / % Effect - - -
Other arthropod (1) LR50 g ha-1 1000 48 hour
A5 Aphidius rhopalosiphi
-
% Effect - - -
Other arthropod (2) LR50 g ha-1 1000 7 day
A5 Typhlodromus pyri
-
% Effect - - -
Soil micro-organisms Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect
A5
Dose: 6.97 mg kg-1 soil, 28 days
-
Mesocosm study data NOEAEC mg l-1 - - -
NOEAEC mg l-1 - - -


HUMAN HEALTH AND PROTECTION

for isoxaben

General:
Property Click here for information on the parameters used to describe human health and protection issues Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with human health and protection data Interpretation Click here for information on the way in which we interpret human health and protection data
Threshold of Toxicological Concern (Cramer Class) Click here for a note on the limitations of the Cramer class High (class III) - -
Mammals - Acute oral LD50 (mg kg-1) > 10000 A5 Rat Low
Mammals - Dermal LD50 (mg kg-1 body weight) > 2000 A5 Rat -
Mammals - Inhalation LC50 (mg l-1) 2.68 A5 Rat, 4 hr (nose only) -
Other Mammal toxicity endpoints - -
ADI - Acceptable Daily Intake (mg kg-1bw day-1) 0.05 A5 SF=100 -
ARfD - Acute Reference Dose (mg kg-1bw day-1) None allocated A5 Dog, SF=100 -
AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) - - -
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) 0.25 A5 Dog, SF = 435 -
Dermal penetration studies (%) 6.6-16.7 A5 concentration dependent -
Dangerous Substances Directive 76/464 - - -
Exposure Limits - - -
Exposure Routes Public Negligible risk to bystanders
Dietary exposure considered to be low risk
Occupational Risk of exposure acceptable under label recommendations for use for personal protection clothing and equipment
European MRLs Click here for the EU MRL pesticide database
Drinking Water Standards - - -
Drinking Water MAC (μg l-1) 0.1 EU Dir 89/778/EC limit; A5 -

Health issues:
Carcinogen Mutagen Endocrine disrupter Reproduction / development effects Cholinesterase inhibitor Neurotoxicant

-

-

Respiratory tract irritant Skin irritant Skin sensitiser Eye irritant Phototoxicant

-

-

General human health issues Bioaccumulates
Possible liver toxicant
USEPA - some evidence to suggest possible human carcinogen

: Yes, known to cause a problem
: No, known not to cause a problem
: Possibly, status not identified
- : No data found

Handling issues:
Property Click here for information on the parameters used to describe substance handling issues Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with data on handling issues Interpretation Click here for information on the way in which we interpret data on handling issues
General Click here for a description of the International Maritime Dangerous Goods (IMDG) codes Not explosive or oxidising
CLP classification 2013 Environment: H413
EC Risk Classification Click here to view information omn the EU risk phrases N - Dangerous for the environment: R50, R53
EC Safety Classification Click here to view information omn the EU safety phrases S60, S61
WHO Classification U - Unlikely to present an acute hazard
US EPA Classification (formulation) IV - Caution - Not acutely toxic
UN Number -
Waste disposal & packaging Click here for a description of UN packaging marks -


TRANSLATIONS

for isoxaben

Language Name
English isoxaben
French isoxaben
German Isoxaben
Danish isoxaben
Italian isoxaben
Spanish isoxaben
Greek -
Slovenian izoksaben
Polish izoksaben
Swedish isoxaben
Hungarian -
Dutch -

Record last updated: Wednesday 23 May 2018
Contact: aeru@herts.ac.uk
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