hymexazol (Ref: F 319) ** hydroxyisoxazole ** SF 6505 ** Translations

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GENERAL INFORMATION
for hymexazol

Description: A systemic fungicide used to control soil-borne diseases caused by Fusaruim, Aphanomyces and Pythium spp.

Example pests controlled: Fusarium crown rot; Root rot; Stem rot

Example applications: Rice; Sugarbeet; Fodder beet; Vegetables; Tomatoes; Ornamentals

Efficacy & activity: -

Availability status: Current

Introduction & key dates: 1966, first reported; 1969, Introduced Japan

EC Regulation 1107/2009 (repealing 91/414):

Status	Approved
Dossier rapporteur/co-rapporteur	Austria/Sweden
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:

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

Chemical structure:

Isomerism	None
Chemical formula	C4H5NO2
Canonical SMILES	CC1=CC(=O)NO1
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	KGVPNLBXJKTABS-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C4H5NO2/c1-3-2-4(6)5-7-3/h2H,1H3,(H,5,6)
2D structure diagram/image available?	Yes

General status:

Pesticide type	Fungicide
Substance group	Oxazole
Minimum active substance purity	985 g/kg
Known relevant impurities	EU dossier - None declared
Substance origin	Synthetic
Mode of action	Systemic, inhibits fungal growth by inhibiting nucleic acid synthesis (DNA / RNA synthesis).
CAS RN	10004-44-1
EC number	233-000-6
CIPAC number	528
US EPA chemical code	-
PubChem CID	24781
Molecular mass (g mol-1)	99.15
PIN (Preferred Identification Name)	-
IUPAC name	5-methylisoxazol-3-ol
CAS name	5-methyl-3(2H)-isoxazolone
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)	32
Examples of recorded resistance	-
Physical state	Colourless to pale yellow coloured crystals
Related substances & organisms	pencycuron

Formulations:

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Bayer CropScience Summit Agro AgroCare Sanko
Example products using this active	Tachigaren WP Terrazol Hymexate Sound
UK LERAP status	None
Formulation and application details	Often supplied as a wettable powder, dusts , emulsifiable concentrates and seed treatments.

ENVIRONMENTAL FATE
for hymexazol

Property		Value	Source/Quality Score/Other Information	Interpretation
Solubility - In water at 20oC (mg l-1)		65100	A5	High
Solubility - In organic solvents at 20oC (mg l-1)		730000	A5 - Acetone	-
		200000	C3 - Benzene	-
		12200	A5 - Hexane	-
		968000	A5 - Methanol	-
Melting point (oC)		83.9	A5	-
Boiling point (oC)		Decomposes before boiling	A5	-
Degradation point (oC)		180	A5	-
Flashpoint (oC)		203	L3	-
Octanol-water partition coefficient at pH 7, 20oC	P	2.00 X 1000	Calculated	-
	Log P	0.3	A4	Low
Bulk density (g ml-1)/Specific gravity		0.55	L3	-
Dissociation constant (pKa) at 25oC		5.92	A5	-
		Note: Weak acid
Vapour pressure at 20oC (mPa)		182	A5	Highly volatile
Henry's law constant at 25oC (Pa m3 mol-1)		1.40 X 10-04	A5	Non-volatile
GUS leaching potential index		2.63	Calculated	Transition state
SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate	Value	1.11 X 10-01	Calculated	-
	Note	-
Potential for particle bound transport index		-	Calculated	Low
Maximum UV-vis absorption L mol-1 cm-1		Neutral solution: 205.6nm = 6796.4; [Acidic solution: 201.9nm = 10344; [Basic solution: 212.9nm = 5077	A5	-
Surface tension (mN m-1)		72.1	A5 at 20oC	-

Degradation:

Property		Value	Source/Quality Score/Other Information	Interpretation
General biodegradability		-
Soil degradation (days) (aerobic)	DT50 (typical)	30	W4	Moderately persistent
	DT50 (lab at 20oC)	14.8	A5	Non-persistent
	DT50 (field)	11.1	A5	Non-persistent
	DT90 (lab at 20oC)	113.4	A5	-
	DT90 (field)	36.8	A5	-
	DT50 modelling endpoint	-	-	-
	Note	EU dossier lab studies DT50 range 6.6-31.5 days, DT90 range 26.2-335 days; Field studies (DAR) DT50 range 3.5-26 days; DT90 range
Dissipation rate RL50 on plant matrix	Value	-	-	-
	Note	-
Dissipation rate RL50 on and in plant matrix	Value	3.1	R4	-
	Note	Published literature RL50 range 2.9-3.3 days, 3 field crops, various matrices, n=8
Aqueous photolysis DT50 (days) at pH 7	Value	Stable	A5	-
	Note	-
Aqueous hydrolysis DT50 (days) at 20oC and pH 7	Value	Stable	A5	-
	Note	Stable pH 5 to 9 @ 20 DegC
Water-sediment DT50 (days)		5.9	A5	Fast
Water phase only DT50 (days)		5.8	A5	Moderately fast

Soil adsorption and mobility:

Property		Value	Source/Quality Score/Other Information	Interpretation
Linear	Kd	-	-	-
	Koc	-
	Notes and range	-
Freundlich	Kf	1.14	A5	Mobile
	Kfoc	56.5
	1/n	0.816
	Notes and range	EU dossier Kf range 0.15-3.09, Kfoc range 12-124 mL/g, 1/n range 0.74-0.93, Soils=5
pH sensitivity		Yes. Adsorption weaker on alkalaine soils.

Other known metabolites:

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction	Metabolising enzymes
acetoacetic acid	-	Water	-	-
acetoacetimide	-	Soil (anaerobic)	-	-
crotonic acid	-	Soil (anaerobic)	-	-
hymexanil-O-glucoside	-	Plant	-	-
hymexazol-O-diglucoside	-	Plant	-	-
hymexazol-N-monoglucoside	-	Plant	-	-
5-methyl-2(3H)-oxazolone (Ref: RMH-1915)	-	Water	0.172	-

ECOTOXICOLOGY
for hymexazol

Property		Value	Source/Quality Score/Other Information	Interpretation
Bio-concentration factor	BCF (l kg-1)	0.49	Q2 Estimated	Low potential
	CT50 (days)	Not available		-
Mammals - Acute oral LD50 (mg kg-1)		1600	A5 Rat	Moderate
Mammals - Short term dietary NOEL	(mg kg-1)	19	L2 Rat, 2 year	High
	(ppm diet)	-		-
Birds - Acute LD50 (mg kg-1)		> 1085	A5 Coturnix japonica	Moderate
Birds - Short term dietary (LC50/LD50)		> 5200 mg kg feed-1	A5 Coturnix japonica	-
Fish - Acute 96 hour LC50 (mg l-1)		> 100	A5 Oncorhynchus mykiss	Low
Fish - Chronic 21 day NOEC (mg l-1)		> 100	A5 Oncorhynchus mykiss	Low
Aquatic invertebrates - Acute 48 hour EC50 (mg l-1)		28	A5 Daphnia magna	Moderate
Aquatic invertebrates - Chronic 21 day NOEC (mg l-1)		0.8	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)		1.6	A5 Chironomus riparius	Moderate
Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg-1)		-	-	-
Aquatic plants - Acute 7 day EC50, biomass (mg l-1)		8.8	F4 Lemna gibba	Moderate
Non-target plants		-	-	-
		-	-	-
Algae - Acute 72 hour EC50, growth (mg l-1)		36	F3 Pseudokirchneriella subcapitata, 5 day	Low
Algae - Chronic 96 hour NOEC, growth (mg l-1)		-	-	-
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)		281.9	A5 Eisenia foetida	Moderate
Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1)		-	-	-
Other soil macro-organisms - e.g. Collembola	LR50 / EC50 / NOEC / % Effect	-	-	-
Other arthropod (1)	LR50 g ha-1	1426	A5 Aphidius rhopalosiphi	-
	% Effect	-	-	-
Other arthropod (2)	LR50 g ha-1	1107	A5 Typhlodromus pyri	-
	% Effect	-	-	-
Soil micro-organisms		-	-	-
Mesocosm study data	NOEAEC mg l-1	-	-	-
	NOEAEC mg l-1	-	-	-

HUMAN HEALTH AND PROTECTION
for hymexazol

General:

Property		Value	Source/Quality Score/Other Information	Interpretation
Threshold of Toxicological Concern (Cramer Class)		High (class III)	-	-
Mammals - Acute oral LD50 (mg kg-1)		1600	A5 Rat	Moderate
Mammals - Dermal LD50 (mg kg-1 body weight)		> 2000	A5 Rabbit	-
Mammals - Inhalation LC50 (mg l-1)		> 0.65	A5 Rat, 4 hr	-
Other Mammal toxicity endpoints		-		-
ADI - Acceptable Daily Intake (mg kg-1bw day-1)		0.17	A5 Rat, SF=100	-
ARfD - Acute Reference Dose (mg kg-1bw day-1)		0.5	A5 Rabbit, 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)		0.17	A5 Dog, SF=100	-
Dermal penetration studies (%)		100	A3 default	-
Dangerous Substances Directive 76/464		-	-	-
Exposure Limits		-	-	-
Exposure Routes	Public	-
	Occupational	PPE/PPC advised
European MRLs		Click here for the EU MRL pesticide database
Drinking Water Standards		-	-	-
Drinking Water MAC (μg l-1)		-	-	-

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		Highly toxic Risk of serious damage to eyes Liver, thyroid and kidney toxicant

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

Handling issues:

Property		Value	Source/Quality Score/Other Information	Interpretation
General		Not explosive or oxidising IMDG Transport Code is usually 3
CLP classification 2013		Health: H302, H318 Environment: H412
EC Risk Classification		Xn - Harmful: R22, R41 N - Dangerous for the environment: R52, R53
EC Safety Classification		S2, S26, S39, S61
WHO Classification		III	-	Slightly hazardous
US EPA Classification (formulation)		III	-	Caution - Slightly toxic
UN Number		Usually 1325
Waste disposal & packaging		Packaging Group III (minor danger)

TRANSLATIONS
for hymexazol

Language	Name
English	hymexazol
French	hymexazol
German	Hymexazol
Danish	hymexazol
Italian	hymexazol
Spanish	hymexazol
Greek	-
Slovenian	himeksazol
Polish	hymeksazol
Swedish	hymexazol
Hungarian	himexazol
Dutch	-

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Record last updated: Thursday 23 August 2018
Contact: aeru@herts.ac.uk