oryzalin (Ref: EL 119) ** dinitrodipropylsulfanilamide ** dirimal ** surflan ** Translations

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SUMMARY

Oryzalin is a pre-emergence surface-applied herbicide that is not approved for use in the EU. It has a low aqueous solubility, is not volatile and, based on its chemical properties, is not expected to leach to groundwater. However, groundwater monitoring programmes have ientified it as a pollutant. It generally tends not to be persistent in soil or water systems. It has a low mammalian toxicity and is a potential carcinogen. It is moderately toxic to birds, most aquatic organisms, honeybees and earthworms.

GENERAL INFORMATION
for oryzalin

Description: A pre-emergence surface-applied herbicide used for control of annual grasses and broad-leaved weeds in fruit trees and around ornamentals

Example pests controlled: Annual grass weeds including Barnyardgrass; Pigeon grass; Crabgrass; Guinea grass; Broad-leaved weeds including Deadnettle, Fathen; Pigweeds; Nightshade

Example applications: Fruit including citrus, stone fruit, apples, pears and berries; Nuts; Vines; Christmas trees; Ornamental trees; Nursery stock

Efficacy & activity: -

Availability status: Current

Introduction & key dates: 1973

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

Status	Approved
Dossier rapporteur/co-rapporteur	Netherlands/France
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

Also used in: Australia, USA

Chemical structure:

Isomerism	-
Chemical formula	C12H18N4O6S
Canonical SMILES	CCCN(CCC)C1=C(C=C(C=C1[N+](=O)[O-])S(=O)(=O)N)[N+](=O)[O-]
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	UNAHYJYOSSSJHH-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C12H18N4O6S/c1-3-5-14(6-4-2)12-10(15(17)18)7-9(23(13,21)22)8-11(12)16(19)20/h7-8H,3-6H2,1-2H3,(H2,13,21,22)
Structure diagram/image available?	Yes

General status:

Pesticide type	Herbicide
Substance group	Dinitroaniline
Minimum active substance purity	960 g/kg
Known relevant impurities	EU dossier - N-nitrosodipropylamine 0.1 mg/kg; toluene 4g/kg
Substance origin	Synthetic
Mode of action	Selective affecting physiological growth process. Microtubule assembly inhibition.
CAS RN	19044-88-3
EC number	242-777-0
CIPAC number	537
US EPA chemical code	104201
PubChem CID	29393
Molecular mass (g mol-1)	346.4
PIN (Preferred Identification Name)	-
IUPAC name	3,5-dinitro-N4,N4-dipropylsulfanilamide
CAS name	4-(dipropylamino)-3,5-dinitrobenzenesulfonamide
Other status information	Potential groundwater contaminant
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	K1
Herbicide Resistance Classification (WSSA)	3
Insecticide Resistance Classification (IRAC)	Not applicable
Fungicide Resistance Classification (FRAC)	Not applicable
Examples of recorded resistance	-
Physical state	Orange crystalline powder
Related substances & organisms	-

Formulations:

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Dow AgroSciences Elanco
Example products using this active	Surflan Dirimal Ryzelan
UK LERAP status	No UK approval for use as a pesticide under EC Regulation 1107/2009
Formulation and application details	Usually supplied as an aqueous suspension or wettable powder.

ENVIRONMENTAL FATE
for oryzalin

Property		Value	Source/Quality Score/Other Information	Interpretation
Solubility - In water at 20oC (mg l-1)		1.13	A5	Low
Solubility - In organic solvents at 20oC (mg l-1)		250000	A5 - Acetone	-
		91900	A5 - Methanol	-
		0.709	A5 - n-Heptane	-
		1570	A5 - Xylene	-
Melting point (oC)		139.7	A5	-
Boiling point (oC)		Decomposes before boiling	A5	-
Degradation point (oC)		213	A5	-
Flashpoint (oC)		Not expected to self ignite; Not highly flammable	A5	-
Octanol-water partition coefficient at pH 7, 20oC	P	5.37 X 1003	Calculated	-
	Log P	3.73	G4	High
Bulk density (g ml-1)/Specific gravity		1.2	L3	-
Dissociation constant (pKa) at 25oC		9.4	A5	-
		Note: Very weak acid
Vapour pressure at 20oC (mPa)		1.1 X 10-07	A5	Low volatility
Henry's law constant at 25oC (Pa m3 mol-1)		3.37 X 10-08	A5	Non-volatile
GUS leaching potential index		2.22	Calculated	Transition state
SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate	Value	1.10 X 10-01	Calculated	-
	Note	-
Potential for particle bound transport index		-	Calculated	Medium
Maximum UV-vis absorption L mol-1 cm-1		Neutral solution: 208nm = 17200, 282nm = 97600, 380nm = 2690; [Acidic solution: 206nm = 17500, 282nm = 380nm = 2740; [Basic solution: 218nm = 14600, 273nm = 10100, 393nm = 2020	A5	-
Surface tension (mN m-1)		63.5	A5	-

Degradation:

Property		Value	Source/Quality Score/Other Information	Interpretation
General biodegradability		-
Soil degradation (days) (aerobic)	DT50 (typical)	44.8	A5	Moderately persistent
	DT50 (lab at 20oC)	88	A5	Moderately persistent
	DT50 (field)	98.2	A5	Moderately persistent
	DT90 (lab at 20oC)	559	A5	-
	DT90 (field)	184.9	A5	-
	DT50 modelling endpoint	-	-	-
	Note	EU dossier lab studies DT50 range 32-456 days, DT90 range 100-1553 days, field studies DT50 range 10.9-113.2 days, DT90 range 66-376 days ; Other sources: DT50 20 days (DW4)
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	0.08	A5	Fast
	Note	DT50 1.4 hours sterile water, 1.6 hours river water
Aqueous hydrolysis DT50 (days) at 20oC and pH 7	Value	Stable	A5	-
	Note	Stable pH 3 to pH 9 at 25 degC
Water-sediment DT50 (days)		32.7	A5	Moderately fast
Water phase only DT50 (days)		5.9	A5	Moderately fast

Soil adsorption and mobility:

Property		Value	Source/Quality Score/Other Information	Interpretation
Linear	Kd	13.0	A5	Slightly mobile
	Koc	949
	Notes and range	EU dossier Kd range 5.23-25.21 mL/g, Koc range 441-1596 mL/g, Soils=12
Freundlich	Kf	4.93	A5	Slightly mobile
	Kfoc	724
	1/n	0.943
	Notes and range	EU dossier Kf range 4.83-5.04, Kfoc range 439-1008, 1/n = 0.926-0.943
pH sensitivity		No

Key metabolites:

Metabolite		Formation medium	Estimated maximum occurrence fraction	1107/2009 relevancy
4-hydroxy-3,5-dinitro-benzenesulfonamide		Soil	0.047	Minor fraction, Relevant

Other known metabolites:

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction	Metabolising enzymes
7-amino-2-ethyl-1-propyl-1H-benzimidazole-5-sulfonamide	OR-14	Soil (Anaerobic)	Soil=0.13	-
2-ethyl-7-nitro-1-propyl-5-sulfonylamino-benzimidazole-3-oxide	OR-13	Water (Photolysis); Groundwater	-	-
3,4-diamino-5-nitrobenzensulfonamide	OR-6	Water (Photolysis)	-	-
2-ethyl-7-nitro-1hydroxy-benzimidazole-5-sulfonamide	OR-15-OH	Water (Photolysis); Groundwater	-	-
2-ethyl-7-nitro-1H-benzimidazole-5-sulfonamide	OR-15	Water (Photolysis)	-	-
7-amino-2-ethyl-1H-benzimidazole-5-sulfonamide	OR-16	Soil	Soil=0.053	-
N-nitroso-N-propylpropan-1-amine	-	-	-	-

ECOTOXICOLOGY
for oryzalin

Property		Value	Source/Quality Score/Other Information	Interpretation
Bio-concentration factor	BCF (l kg-1)	66.1	A5 Whole fish	Low potential
	CT50 (days)	0.6		-
Mammals - Acute oral LD50 (mg kg-1)		> 5000	A5 Rat	Low
Mammals - Short term dietary NOEL	(mg kg-1)	-	L2 Rat, 2 year	-
	(ppm diet)	> 300		-
Birds - Acute LD50 (mg kg-1)		427	A3 Anas platyrhynchos	Moderate
Birds - Short term dietary (LC50/LD50)		> 1351 mg kg bw-1 day-1	A5 Anas platyrhynchos	-
Fish - Acute 96 hour LC50 (mg l-1)		2.86	A5 Oncorhynchus mykiss	Moderate
Fish - Chronic 21 day NOEC (mg l-1)		0.46	A5 Oncorhynchus mykiss	Moderate
Aquatic invertebrates - Acute 48 hour EC50 (mg l-1)		1.02	A5 Daphnia magna	Moderate
Aquatic invertebrates - Chronic 21 day NOEC (mg l-1)		0.36	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)		1.0	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)		0.0154	A5 Lemna gibba	Moderate
Non-target plants		26.0	A5 Ryegrass Seedling emergence, ER50 as g/ha	-
		53.9	A5 Lettuce Seedling emergence, ER50 as g/ha	-
Algae - Acute 72 hour EC50, growth (mg l-1)		18.1	A5 Anabaena flos-aquae	Low
Algae - Chronic 96 hour NOEC, growth (mg l-1)		-	-	-
Honeybees	Contact acute 48 hour LD50 (μg bee-1)	40.8	A5	Moderate
	Oral acute 48 hour LD50 (μg bee-1)	32	A5	Moderate
	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)		34.3	A5 Eisenia foetida	Moderate
Other soil macro-organisms - e.g. Collembola	LR50 / EC50 / NOEC / % Effect	2.66	A5 Folsomia candida, 4 Week NOEC mg kg-1	-
Other arthropod (1)	LR50 g ha-1	3852	> A4 Aphidius rhopalosiphi	-
	% Effect	-	-	-
Other arthropod (2)	LR50 g ha-1	3852	> A4 Typhlodromus pyri	-
	% Effect	-	-	-
Soil micro-organisms		Nitrogen mineralisation: No significant adverse effect Carbon mineralisation: No significant adverse effect	A5 Dose: 25.6 mg kg-1 soil, 28 days	-
Mesocosm study data	NOEAEC mg l-1	-	-	-
	NOEAEC mg l-1	-	-	-

HUMAN HEALTH AND PROTECTION
for oryzalin

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)		> 5000	A5 Rat	Low
Mammals - Dermal LD50 (mg kg-1 body weight)		> 2000	A5 Rabbit	-
Mammals - Inhalation LC50 (mg l-1)		> 4.79	A5 Rat, 4 hr (nose only)	-
Other Mammal toxicity endpoints		-		-
ADI - Acceptable Daily Intake (mg kg-1bw day-1)		0.005	A5	-
ARfD - Acute Reference Dose (mg kg-1bw day-1)		None allocated	A5	-
AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1)		-	-	-
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1)		0.05	A5	-
Dermal penetration studies (%)		2.5-2.8	A5 concentration dependent	-
Dangerous Substances Directive 76/464		-	-	-
Exposure Limits		-	-	-
Exposure Routes	Public	Very small risk of exposure of bystanders via drift
	Occupational	No unacceptable risks to operators or other workers identified
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 Calc MAC=50 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		Bioaccumulates Potential liver, kidney & spleen toxicant USEPA - probable 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		Value	Source/Quality Score/Other Information	Interpretation
General		Not oxidising Classified as explosive category E
CLP classification 2013		-
EC Risk Classification		Carcinogen category 3: R40 Xn - Harmful: R43 N - Dangerous for the environment: R50, R53
EC Safety Classification		-
WHO Classification		U	-	Unlikely to present an acute hazard
US EPA Classification (formulation)		III	-	Caution - Slightly toxic
UN Number		Usually 3077
Waste disposal & packaging		-

TRANSLATIONS
for oryzalin

Language	Name
English	oryzalin
French	oryzalin
German	Oryzalin
Danish	oryzalin
Italian	oryzalin
Spanish	orizalina
Greek	-
Slovenian	orizalin
Polish	oryzalina
Swedish	-
Hungarian	-
Dutch	-

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