Carboxin (Ref: D 735)

Carboxin (Ref: D 735)	Last updated: 12/01/2021
(Also known as: carboxine; carbathiin; vitavax)

SUMMARY

Carboxin is an effective agricultural fungicide that is approved for use in the EU subject to Member State approval. It is moderately soluble in water, is non-volatile and, based on its chemical properties, would not normally be expected to leach to groundwater. It tends not to persist in soil or water systems. Whilst it is an irritant, its mammalian toxicity is low and no significant health effects have been identified. It shows a low or moderate ecotoxicity to most species.

GENERAL INFORMATION

Description

An anilide fungicide for bunts and smuts normally that is normally used as a seed treatment

Example pests controlled

Smut; Rots; Bunt; Blight; Leaf stripe; Net blotch

Example applications

Rice; Vegetables; Corn; Wheat; Barley; Oats; Turf grass; Cotton

Efficacy & activity

Carboxin has been shown to be an effective fungicide via field trials and long use globally.

Availability status

Current

Introduction & key dates

1966, first reported; 1969, first introduced

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Not applicable

UK LERAP status

Not applicable

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Date EC 1107/2009 inclusion expires

31/05/2021

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

Australia, USA

Chemical structure

Isomerism

None

Chemical formula

C₁₂H₁₃NO₂S

Canonical SMILES

CC1=C(SCCO1)C(=O)NC2=CC=CC=C2

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

GYSSRZJIHXQEHQ-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C12H13NO2S/c1-9-11(16-8-7-15-9)12(14)13-10-5-3-2-4-6-10/h2-6H,7-8H2,1H3,(H,13,14)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
carboxin	-

General status

Pesticide type

Fungicide

Substance group

Oxathiin

Minimum active substance purity

970 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Systemic, inhibits mitochondrial function. Succinate Dehydrogenase Inhibitor.

CAS RN

5234-68-4

EC number

226-031-1

CIPAC number

273

US EPA chemical code

090201

PubChem CID

21307

Molecular mass

235.30

PIN (Preferred Identification Name)

2-methyl-N-phenyl-5,6-dihydro-1,4-oxathiine-3-carboxamide

IUPAC name

5,6-dihydro-2-methyl-1,4-oxathiine-3-carboxanilide

CAS name

5,6-dihydro-2-methyl-N-phenyl-1,4-oxathiin-3-carboxamide

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)

Examples of recorded resistance

Physical state

Colourless crystals

Related substances & organisms

thiram

captan

diazinon

clothianidin

Formulations

Property

Value

Example manufacturers & suppliers of products using this active now or historically

Vitavax 200FF
Krisvax
Kemikar

Example products using this active

Chemtura Corp
Crompton Europe
Bayer CropScience
Uniroyal

Formulation and application details

Usually formulated as a flowable concentrate that is diluted with water for use as a seed treament

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

134

Moderate

Solubility - In organic solvents at 20 °C (mg l⁻¹)

220000

Acetone

110000

Ethyl acetate

89000

Methanol

53000

Toluene

Melting point (°C)

91.5

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

210

Flashpoint (°C)

Not expected to self ignite; Not highly flammable

Octanol-water partition coefficient at pH 7, 20 °C

2.00 X 10⁰²

Calculated

Log P

2.3

Low

Bulk density (g ml⁻¹)

1.36

Dissociation constant pKa) at 25 °C

0.5

Strong acid

Vapour pressure at 20 °C (mPa)

0.02

Low volatility

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

3.20 X 10^-05

Non-volatile

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

205nm = 17443, 295nm = 6585

Surface tension (mN m⁻¹)

61.2

at 20°C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

0.5

Non-persistent

DT₅₀ (lab at 20 °C)

0.28

Non-persistent

DT₅₀ (field)

3.3

Non-persistent

DT₉₀ (lab at 20 °C)

1.99

Non-persistent

DT₉₀ (field)

11.1

DT₅₀ modelling endpoint

Note

EU dossier Lab studies DT₅₀ range 0.07-1.68 days, DT₉₀ range 0.23-3.49 days; field studies DT₅₀ range 0.27-11 days, DT₉₀ range 0.9-37 days; Other sources: DT₅₀ 1 day (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

0.1

Fast

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

Stable

Note

Stable between pH 4 and pH 9

Water-sediment DT₅₀ (days)

17.3

Fast

Water phase only DT₅₀ (days)

13.6

Moderately fast

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

1.3

Moderately mobile

K_oc

99.4

Notes and range

EU dossier K_d range 1.03-1.78 mL g⁻¹, K_oc range 81-124 mL g⁻¹, Soils=5

Freundlich

K_f

1.95

Very mobile

K_foc

1.3

¹/_n

0.80

Notes and range

EU dossier K_f range 1.56-2.71 mL g⁻¹, K_foc range 123-213 mL g⁻¹, ¹/_n range 0.79-0.81, Soils=5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

2.01

Calculated

Transition state

SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate

Value

3.83 X 10^-03

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

Key metabolites

Metabolite

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

carboxin sulfoxide

Soil

0.782

Major fraction, Relevant

oxycarboxin (Ref: F 461)

Soil

0.170

Major, Relevant

oxathiine amide sulfoxide

Soil

0.274

Major fraction, Relevant

oxathiine amide sulfone

Soil

0.145

Major fraction, Relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

4-hydroxycarboxin sulfone

carboxin Rat M03

Rat (Urine & Bile)

4-O-glucuronyl-2-hydroxycarboxin

carboxin Rat M04

Rat (Urine)

4-hydroxycarboxin

carboxin Rat M07

Rat (Urine, Faeces & Bile)

monomethoxy dihydroxycarboxin

carboxin Rat M09

Rat (Urine & Faeces)

2-methoxycarboxin sulfoxide-4-glucuronide

carboxin Rat M11

Rat (Bile & Urine)

4-O-glucuronyl carboxin

carboxin Rat M12

Rat (Bile)

2-[2-anilino-2-oxoacetyl)thio]ethyl acetate

Soil; Water; Groundwater

2-hydroxy-2-methyl-N-phenyl-1,4-oxathiane-3-carboxamide-4-oxide

hydrated carbon sulfoxide; carboxin M09

Soil; Water; Groundwater

2-methyl-5,6-dihydro-1,4-oxathiine-3-carboxylic acid-4-oxide

PH-3; alpha-vinylsulfinyl acetanilide; P/V-05; M234

Soil; Water; Groundwater

4-O-glucuronyl carboxin sulfoxide

carboxin Rat M01

Rat (Urine & Bile)

4-hydroxycarboxin sulfoxide

carboxin Rat M02

Rat (Urine & Bile)

acetanilide

Plant

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

Estimated

Low potential

CT₅₀ (days)

Not available

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

2588

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

5.5

Rat

High

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Rat (male) Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2150

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5000 mg kg feed⁻¹

Colinus virginianus

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Colinius virginianus

Moderate

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

2.3

Oncorhynchus mykiss

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

0.32

Cyprinidae

Moderate

Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

> 57

Daphnia magna

Moderate

Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

0.32

Daphnia magna 17 day

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)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)

0.92

Lemna gibba

Moderate

Non-target plants

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

0.48

Pseudokirchneriella subcapitata

Moderate

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)

> 100

Apis mellifera

Low

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

> 100

Apis mellifera

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)

> 250

Eisenia foetida

Moderate

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

Eisenia foetida

Moderate

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

0 / -21.5

Mortality / Reproduction [Dose: 776 mg carboxin + 770 mg thiram/kg seed]
Aleochara bilineata adult/juvenile

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect

Dose: 660 g ha⁻¹

Mesocosm study data

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)

2588

Rat

Low

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

4000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 4.7

Rat 4 hr

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

0.008

Rat 2 year SF=100

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

None allocated

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

0.055

Rat SF=100

Dermal penetration studies (%)

3.3-5.0

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Negligible risk to the public due to pattern of use

Occupational

Acceptable risks with PPE/PPC

European MRLs

EU MRL pesticide database

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

0.1

EU Dir 89/778/EC limit; Calc MAC=4.8 µg l⁻¹

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Mild skin sensitiser
Possible kidney toxicant

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising

CLP classification 2013

Health: H302, H312, H317, H332, H373; Environment: H400, H410

EC Risk Classification

Carcinogen category 3: R40
Xn - Harmful: R43
N - Dangerous for the environment: R50, R53

EC Safety Classification

S36/37, S60, S61

WHO Classification

III (Slightly hazardous)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

carboxin

French

carboxine

German

Carboxin

Danish

carboxin

Italian

carbossina

Spanish

carboxina

Greek

carboxin

Polish

karboksyna

Swedish

karboxin

Hungarian

karboxin

Dutch

carboxin

Record last updated:	12/01/2021
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