Sulphadimethoxine	Last updated: 25/01/2024
(Also known as: sulfadimethoxine; sulfadimetoxin; SDM)

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GENERAL INFORMATION

Description	Broad spectrum sulphonamide drug with veterinary applications which is usually formulated as the sodium salt.
Availability status	Current
Introduction & key dates	-
Examples of veterinary uses	Used to treat a variety of infections including those of the respiratory tract, urinary tract and soft tissue infections. It is also used for the treatment of coccidiosis.
Examples of species treated	Dogs; Horses; Cattle; Birds; Cats; Dogs; Poultry; Pigs; Sheep

Approval status

VMR 2013/2033 approval status (GB/UK)	Approved
EU Regulatory approval status	Approved

Chemical structure

Isomerism	-
Chemical formula	C₁₂H₁₄N₄O₄S
Canonical SMILES	COC1=NC(=NC(=C1)NS(=O)(=O)C2=CC=C(C=C2)N)OC
Isomeric SMILES	-
International Chemical Identifier key (InChIKey)	ZZORFUFYDOWNEF-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C12H14N4O4S/c1-19-11-7-10(14-12(15-11)20-2)16-21(17,18)9-5-3-8(13)4-6-9/h3-7H,13H2,1-2H3,(H,14,15,16)
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
sulphadimethoxine	-

General status

Veterinary substance type	Antibiotic, Antibacterial, Antiprotozoal, Coccidiostat, Antiparasitic, Medicinal drug
Substance groups	Sulphonamide
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Inhibits the conversion of para-aminobenzoic acid to dihydrofolic acid and so inhibits bacterial synthesis
Molecular targets	[Cytochrome P450 2C9, Inhibitor]
CAS RN	122-11-2
EC number	204-523-7
CIPAC number	-
US EPA chemical code	-
PubChem CID	-
Therapeutic Class	Antiinfectants for systemic use: Antibacterials for systemic use, Antiprotozoals
ATCvet Code	QJ01EQ09; QP51AG02
Controlled Drug?	No
Regulation 37/2010 MRL Classification	Allowed substance (Table 1: All food producing species)
Molecular mass	310.33
PIN (Preferred Identification Name)	-
IUPAC name	4-amino-N-(2,6-dimethoxypyrimidin-4-yl)benzenesulfonamide
CAS name	4-amino-N-(2,6-dimethoxy-4-pyrimidinyl)benzolsulfonamid
Other status information	-
Relevant Environmental Water Quality Standards	-
Physical state	White powder
Related substances & organisms	sulphadimethoxine sodium

Formulations

Property	Product	Manufacturer	Authorisation Route	Legal Class (GB/UK)
Example products (past and present) using this active	-	-	-	-
Formulation and application details	Usually supplied as the sodium salt liquid suspension in sachets and given by mouth but also available in tablet form

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		343	V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source	Moderate
Solubility - In organic solvents at 20 °C (mg l⁻¹)		-	-	-
Melting point (°C)		200	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Boiling point (°C)		Decomposes before boiling	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	4.27 X 1000	Calculated	-
	Log P	0.63	R4 R = Peer reviewed scientific publications 4 = Verified data	Low
Fat solubility of residues	Solubility	-	-	-
	Data type	-	-	-
Density (g ml⁻¹)		-	-	-
Dissociation constant pKa) at 25 °C		5.54	R4 R = Peer reviewed scientific publications 4 = Verified data	-
		-
Vapour pressure at 20 °C (mPa)		2.11 X 10-04	R4 R = Peer reviewed scientific publications 4 = Verified data	Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		-	-	-
Volatilisation as max % of applied dose lost	From plant surface	-	-	-
	From soil surface	-	-	-
Maximum UV-vis absorption L mol⁻¹ cm⁻¹		-	-	-
Surface tension (mN m⁻¹)		-	-	-
Refractive Index		-	-	-
Environmental release		-

Degradation

Property		Value	Source; quality score; and other information	Interpretation
Soil degradation (days) (aerobic)	DT₅₀ (typical)	-	-	-
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	Note	-
Manure DT₅₀ (days)		-	-	-
Aqueous photolysis DT₅₀ (days) at pH 7	Value	-	-	-
	Note	-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7	Value	-	-	-
	Note	-
Water-sediment DT₅₀ (days)		-	-	-
Water phase only DT₅₀ (days)		-	-	-
Sediment phase only DT₅₀ (days)		-	-	-
Air degradation		As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.
Decay in stored produce DT₅₀		-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd (mL g⁻¹)	-	R4 R = Peer reviewed scientific publications 4 = Verified data	Slightly mobile
	Koc (mL g⁻¹)	1672
	Notes and range	Koc 2517 mL g⁻¹ soil with 81.5% sand, 4856 mL g⁻¹ soil with 52% sand
Freundlich	Kf (mL g⁻¹)	-	-	-
	Kfoc (mL g⁻¹)	-
	1/n	-
	Notes and range	-
pH sensitivity		-

Fate indices

Property		Value	Source; quality score; and other information	Interpretation
GUS leaching potential index		-	-	-
Bio-concentration factor	BCF (l kg⁻¹)	-	-	-
	CT₅₀ (days)	-		-

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property		Value	Source; quality score; and other information	Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		> 1000	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Rabbit	Moderate
Mammals - Short term dietary NOEL	(mg kg⁻¹)	-	-	-
	(ppm diet)	-		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		-	-	-
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)		-	-	-
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)		-	-	-
Soil micro-organisms		-	-	-
Collembola	Acute LC₅₀ (mg kg⁻¹)	-	-	-
	Chronic NOEC (mg kg⁻¹)	-	-	-
Non-target plants		-	-	-
		-	-	-
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)	-	-	-
	Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
	Chronic	-	-	-
	Notes	-
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 bee species (1)	Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)	-	-	-
	Mode of exposure	-
Other bee species (2)	Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)	-	-	-
	Mode of exposure	-
Beneficial insects (Ladybirds)		-	-	-
Beneficial insects (Lacewings)		-	-	-
Beneficial insects (Parasitic wasps)		-	-	-
Beneficial insects (Predatory mites)		-	-	-
Beneficial insects (Ground beetles)		-	-	-

Aquatic ecotoxicology

Property		Value	Source; quality score; and other information	Interpretation
Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		> 400	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source Oncorhynchus mykiss	Low
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		> 1000	R4 R = Peer reviewed scientific publications 4 = Verified data Danio rerio	Low
Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		189	R4 R = Peer reviewed scientific publications 4 = Verified data Daphnia magna	Low
Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (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 (free-floating, growth) - Acute 7 day EC₅₀, biomass (mg l⁻¹)		-	-	-
Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)		-	-	-
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		2.3	R4 R = Peer reviewed scientific publications 4 = Verified data Selenastrum capricornutum	Moderate
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		> 0.53	R4 R = Peer reviewed scientific publications 4 = Verified data Selenastrum capricornutum	Moderate
Mesocosm study data	NOEAEC mg l⁻¹	-	-	-
	NOEAEC mg l⁻¹	-	-	-
Marine bivalves		-	-	-

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)		> 1000	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Rabbit	Moderate
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		-	-	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		-	-	-
Other Mammal toxicity endpoints		Intravenous LD₅₀ = 1000 mg kg⁻¹	V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source Rabbit	-
		Subcutaneous LD₅₀ = 791 mg kg⁻¹	V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source Mouse	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		-	-	-
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	-
Mammalian dose elimination route and rate		Metabolised and excreted mainly in the urine	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor XNo, known not to cause a problem A0 A = Chromosome aberration (EFSA database) 0 = No data ; 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 ✓Yes, known to cause a problem No data found No data found Respiratory tract irritant Skin irritant Skin sensitiser ✓Yes, known to cause a problem ✓Yes, known to cause a problem No data found Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		May cause vomiting and diarrhoea Possible kidney and liver toxicant

Handling issues

Property	Value and interpretation
General	Hygroscopic
CLP classification 2013	-
WHO Classification	Not listed (Not listed)
UN Number	-
Waste disposal & packaging	-
Shelf-life, storage, stability and reactivity	-

TRANSLATIONS

Language	Name
English	sulphadimethoxine
French	-
German	-
Danish	-
Italian	sulfadimetossina
Spanish	sulfametoxina
Greek	-
Polish	-
Swedish	-
Hungarian	-
Dutch	-
Norwegian	-

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Record last updated:	25/01/2024
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