Erythromycin	Last updated: 18/05/2024
(Also known as: EES; abomacetin; abomacetin; erythromycin A)

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GENERAL INFORMATION

Description	A macrolide antibiotic produced by Streptomyces erythreus and used in veterinary medicine
Availability status	Current
Introduction & key dates	1953, patented; 1968, first reviewed
Examples of veterinary uses	Used to treat a range of bacterial infections including mastitis, pneumonia, tick-borne infections like Lyme Disease, sinus infections, wound infections, skin infections, bone infections, and certain other types of bacterial infections
Examples of species treated	Poultry; Cattle; Sheep; Pigs

Approval status

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

Chemical structure

Isomerism	Isomeric
Chemical formula	C₃₇H₆₇NO₁₃
Canonical SMILES	CCC1C(C(C(C(=O)C(CC(C(C(C(C(C(=O)O1)C)OC2CC(C(C(O2)C)O)(C)OC)C)OC3C(C(CC(O3)C)N(C)C)O)(C)O)C)C)O)(C)O
Isomeric SMILES	CC[C@@H]1[C@@]([C@@H]([C@H](C(=O)[C@@H](C[C@@]([C@@H]([C@H]([C@@H]([C@H](C(=O)O1)C)O[C@@H]2C[C@@]([C@H]([C@@H](O2)C)O)(C)OC)C)O[C@H]3[C@@H]([C@H](C[C@H](O3)C)N(C)C)O)(C)O)C)C)O)(C)O
International Chemical Identifier key (InChIKey)	ULGZDMOVFRHVEP-UMCXFAKASA-N
International Chemical Identifier (InChI)	InChI=1S/C37H67NO13/c1-14-25-37(10,45)30(41)20(4)27(39)18(2)16-35(8,44)32(51-34-28(40)24(38(11)12)15-19(3)47-34)21(5)29(22(6)33(43)49-25)50-26-17-36(9,46-13)31(42)23(7)48-26/h18-26,28-32,34,40-42,44-45H,14-17H2,1-13H3/t18-,19+,20+,21+,22-,23+,24-,25-,26+,28+,29+,30-,31+,32-,34-,35-,36-,37-/m1/s1
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
erythromycin B trihydrate	Variant
erythromycin A dihydrate	Variant
erythromycin B dihydrate	Variant
erythromycin A	-

General status

Veterinary substance type	Antibiotic, Antibacterial, Antimicrobial, Medicinal drug
Substance groups	Macrolide
Minimum active substance purity	-
Known relevant impurities	FAO: N-demethyl-erythromycin A; anhydroerythromycin A; erythromycin A enol ether; pseudoerythromycin A enol ether, erythromycin E, erythromycin F
Substance origin	Natural
Mode of action	Inhibits protein synthesis which is the basis of this antimicrobial action
Molecular targets	[3S rRNA, Antagonist], [50S ribosomal protein L22, Antagonist], [50S ribosomal protein L4, Antagonist]
CAS RN	114-07-8
EC number	204-040-1
CIPAC number	-
US EPA chemical code	-
PubChem CID	-
Therapeutic Class	Antiinfectants for systemic use: Antibacterials for intramammary use
ATCvet Code	QJ51FA01
Controlled Drug?	No
Regulation 37/2010 MRL Classification	Allowed substance (Table 1: All food producing species)
Molecular mass	733.93
PIN (Preferred Identification Name)	-
IUPAC name	(3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-6-{[(2S,3R,4S,6R)-4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy}-14-ethyl-7,12,13-trihydroxy-4-{[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy}-3,5,7,9,11,13-hexamethyl-1-oxacyclotetradecane-2,10-dione
CAS name	-
Other status information	-
Relevant Environmental Water Quality Standards	-
Physical state	White to slightly yellow crystalline solid, slightly hygroscopic
Related substances & organisms	tulathromycin A tilmicosin

Formulations

Property	Product	Manufacturer	Authorisation Route	Legal Class (GB/UK)
Example products (past and present) using this active	Erythrocin 16.5% w/w soluble powder for oral solution	Ceva Animal Health Ltd	UK National authorisation (IC)	Prescription only medicine to be authorised by a veterinarian (POM-V)
Formulation and application details	Often formulated as powders or oral use

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		2000	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source	High
Solubility - In organic solvents at 20 °C (mg l⁻¹)		-	-	-
Melting point (°C)		135	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source resolidifies MP(2) = 190	-
Boiling point (°C)		-	-	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	3.02 X 1002	Calculated	-
	Log P	2.48	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data	Low
Fat solubility of residues	Solubility	-	-	-
	Data type	-	-	-
Density (g ml⁻¹)		-	-	-
Dissociation constant pKa) at 25 °C		8.88	R4 R = Peer reviewed scientific publications 4 = Verified data	-
		@ 25DegC
Vapour pressure at 20 °C (mPa)		-	-	-
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		pH 6.3: 280nm	-	-
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)	64	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source	Moderately persistent
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	Note	USEPA data: >64 days in three soils - sandy clay loam, silty clay 7 silty loam
Manure DT₅₀ (days)		11	V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source Temp and OM dependent data for sandy loam+cattle manure 20°C	-
Aqueous photolysis DT₅₀ (days) at pH 7	Value	-	-	-
	Note	-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7	Value	63.0	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source	Moderately persistent
	Note	at pH5 DT₅₀ 0.8 days; at pH9 DT₅₀ 35 days
Water-sediment DT₅₀ (days)		-	-	-
Water 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)	-	V1 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 1 = Estimated data with little or no verification	Slightly mobile
	Koc (mL g⁻¹)	570
	Notes and range	Estimated
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		2.25	Calculated	Transition state
Bio-concentration factor	BCF (l kg⁻¹)	-	-	-
	CT₅₀ (days)	-		-

Known soil and groundwater metabolites

None

Other known metabolites

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction
des-N-methyl-erythromycin Note: Major metabolite; Pharmacologically active	-	Humans (Liver)	-

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property		Value	Source; quality score; and other information	Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		> 4600	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source Rat	Low
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	-	-	-
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)		349	V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source Morone saxatilis	Low
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		-	-	-
Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		30.5	R4 R = Peer reviewed scientific publications 4 = Verified data Daphnia magna	Moderate
Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)		0.25	R4 R = Peer reviewed scientific publications 4 = Verified data Daphnia magna	Moderate
Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		> 0.11	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Ceriodaphnia dubia	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)		> 1000	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Lemna gibba as LOEC	Low
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		0.02	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Pseudokirchneriella subcapitata	Moderate
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		0.01	R4 R = Peer reviewed scientific publications 4 = Verified data Selenastrum capricornutum	Moderate
Mesocosm study data	NOEAEC mg l⁻¹	-	-	-
	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)		> 4600	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source Rat	Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		-	-	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		-	-	-
Other Mammal toxicity endpoints		Subcutaneous LD₅₀ = 427 mg kg⁻¹	V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source Rat	-
		Intravenous LD₅₀ = 426 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		Largely (~95%) metabolised by the liver and excreted in the bile and to lesser extent the urine	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data	-

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 XNo, known not to cause a problem Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant ✓Yes, known to cause a problem No data found ?Possibly, status not identified Respiratory tract irritant Skin irritant Skin sensitiser ?Possibly, status not identified ?Possibly, status not identified No data found Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		May cause diarrhoea, nausea, abdominal pain, and vomiting Reported cases of hearing impairment Kidney, liver and lungs toxicant

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	-
WHO Classification	Not listed (Not listed)
UN Number	-
Waste disposal & packaging	-
Shelf-life, storage, stability and reactivity	-

TRANSLATIONS

Language	Name
English	erythromycin
French	erythromycine
German	-
Danish	-
Italian	-
Spanish	eritromicina
Greek	-
Polish	-
Swedish	-
Hungarian	-
Dutch	-
Norwegian	-

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Record last updated:	18/05/2024
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