Top Environmental Fate Ecotoxicology Human Health Translations
Home
A to Z
Search
Support information
Edit history
Purchasing and licensing
Ivermectin
Last updated: 31/08/2023
(Also known as: 22,23-dihyroavermectin B1)
Data alerts

The following alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement.

Environmental fate Ecotoxicity Human health
Environmental fate
High alert:
Potential for particle bound transport: High
Warning:
Significant data are missing
Ecotoxicity
High alert:
Daphnia acute ecotoxicity: High
Human health
High alert:
Mammals acute toxicity: High
GENERAL INFORMATION
Description
An antiparasitic medication, traditionally used against worms (except tapeworms) but more recently found to be effective against many species of mites and lice
Availability status
-
Introduction & key dates
mid 1980s, introduced as an anthelmintic.
Examples of species treated
Cattle, Pigs, Sheep, Horses
Chemical structure
Isomerism
Chiral molecules. Technical substance contains a mixture of 90% of 5-O-demethyl-22,23-dihydroavermectin A1b (B1a) and about 10% of 5-O-demethyl-25-de(1-methylpropyl)-22,23-dihydro 25–(1-methylethyl)avermectin (B1b)
Chemical formula
C₄₈H₇₄O₁₄ + C₄₇H₇₂O₁₄
Canonical SMILES
CCC(C)C1C(CCC2(O1)CC3CC(O2)CC=C(C(C(C=CC=C4COC5C4(C(C=C(C5O)C)C(=O)O3)O)C)OC6CC(C(C(O6)C)OC7CC(C(C(O7)C)O)OC)OC)C)C
Isomeric SMILES
CC[C@H](C)[C@@H]1[C@H](CC[C@@]2(O1)C[C@@H]3C[C@H](O2)C/C=C(/[C@H]([C@H](/C=C/C=C/4\CO[C@H]5[C@@]4([C@@H](C=C([C@H]5O)C)C(=O)O3)O)C)O[C@H]6C[C@@H]([C@H]([C@@H](O6)C)O[C@H]7C[C@@H]([C@H]([C@@H](O7)C)O)OC)OC)\C)C
International Chemical Identifier key (InChIKey)
AZSNMRSAGSSBNP-XPNPUAGNSA-N
International Chemical Identifier (InChI)
InChI=1S/C48H74O14.C47H72O14/c1-11-25(2)43-28(5)17-18-47(62-43)23-34-20-33(61-47)16-15-27(4)42(26(3)13-12-14-32-24-55-45-40(49)29(6)19-35(46(51)58-34)48(32,45)52)59-39-22-37(54-10)44(31(8)57-39)60-38-21-36(53-9)41(50)30(7)56-38;1-24(2)41-27(5)16-17-46(61-41)22-33-19-32(60-46)15-14-26(4)42(25(3)12-11-13-31-23-54-44-39(48)28(6)18-34(45(50)57-33)47(31,44)51)58-38-21-36(53-10)43(30(8)56-38)59-37-20-35(52-9)40(49)29(7)55-37/h12-15,19,25-26,28,30-31,33-45,49-50,52H,11,16-18,20-24H2,1-10H3;11-14,18,24-25,27,29-30,32-44,48-49,51H,15-17,19-23H2,1-10H3/b13-12+,27-15+,32-14+;12-11+,26-14+,31-13+/t25-,26+,28+,30+,31+,33-,34?,35+,36+,37+,38?,39+,40-,41+,42+,43-,44+,45-,47-,48-;25-,27-,29-,30-,32+,33?,34-,35-,36-,37?,38-,39+,40-,41+,42-,43-,44+,46+,47+/m10/s1
2D structure diagram/image available?
Yes
General status
Veterinary substance type
Insecticide, Acaricide, Antihelmintic
Substance groups
Avermectin
Minimum active substance purity
-
Known relevant impurities
-
Substance origin
Semi-synthetic
Mode of action
Broad spectrum, Glutamate-gated chloride channel (GluCl) allosteric modulator. Induces flaccid paralysis in parasitic nematodes, in vitro.
Molecular targets
[Glycine receptor subunit alpha-3, agonist], [Gamma-aminobutyric-acid (GABA) receptor subunit beta-3, agonist]
CAS RN
70288-86-7
Alternative/old CAS RN
71827-03-7
EC number
274-536-0
CIPAC number
-
US EPA chemical code
-
PubChem CID
-
ATCvet Code
QP54AA01; QS02QA03
Therapeutic Class
Antiparasitic products, insecticides & repellents: Endectocides; Sensory organs: Otologicals
Controlled Drug?
No
Regulation 37/2010 MRL Classification
Allowed substance (Table 1: Mammalian food species)
Molecular mass
861.1
PIN (Preferred Identification Name)
-
IUPAC name
ivermectin (22,23-dihydroavermectin B1a + 22,23-dihydroavermectin B1b)
CAS name
ivermectin
Other status information
-
Relevant Environmental Water Quality Standards
UK Environment Agency non-statutory standard for the protection of aquatic life in fresh surface water: 0.0001 µg l⁻¹ as annual average, 0.001 µg l⁻¹ as max acceptable conc.
UK Environment Agency non-statutory standard for the protection of aquatic life in salt water: 0.001 µg l⁻¹ as annual average, 0.01 µg l⁻¹ as max acceptable conc.
Physical state
Off-white coloured, slightly hydroscopic powdery solid
Related substances & organisms
Formulations
Property
Product
Manufacturer
Authorisation Route
UK Legal Class
Example products using this active
Alstomec 1% injection for Cattle & Pigs Alstoe Animal Health UK National authorisation (IC) Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
Animec 0.8mg/l Oral Solution for Sheep Chanelle Pharmaceuticals EU Mutually recognised procedure Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
Bimectin Oral Suspension Cross Vetpharm Group UK National authorisation Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
Enovex 0.5% Pour-on Solution for Cattle Norbrooks Labs UK National authorisation (IC) Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
Formulation and application details
Available in a variety of foumulations including solution for injection and pour-on solutions
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
4.0
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
Solubility - In organic solvents at 20 °C (mg l⁻¹)
30000
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
Butanol		 -
Melting point (°C)
155
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
 -
Boiling point (°C)
- - -
Degradation point (°C)
- - -
Flashpoint (°C)
- - -
Octanol-water partition coefficient at pH 7, 20 °C
P
- - -
Log P
- - -
Fat solubility of residues
Solubility
- - -
Data type
- - -
Density (g ml⁻¹)
- - -
Dissociation constant pKa) at 25 °C
- - -
-
Vapour pressure at 20 °C (mPa)
- - -
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
- - -
Maximum UV-vis absorption L mol⁻¹ cm⁻¹
In methanol: 238nm = 27100, 245nm = 30100
L3 L = Pesticide manuals and hard copy reference books / other sources
3 = Unverified data of known source
 -
Surface tension (mN m⁻¹)
- - -
Refractive Index
- - -
Degradation
Property
Value
Source; quality score; and other information
Interpretation
Soil degradation (days) (aerobic)
DT₅₀ (typical)
112
R4 R = Peer reviewed scientific publications
4 = Verified data
 Persistent
DT₅₀ (lab at 20 °C)
- - -
DT₅₀ (field)
- - -
DT₉₀ (lab at 20 °C)
- - -
DT₉₀ (field)
- - -
Note
General literature states DT₅₀ range 7 to 240 days
Manure DT₅₀ (days)
>45
R4 R = Peer reviewed scientific publications
4 = Verified data
Other data; DT₅₀ 6 days in dung; 7-14 days soil/faeces mix in summer		 -
Aqueous photolysis DT₅₀ (days) at pH 7
Value
1
R4 R = Peer reviewed scientific publications
4 = Verified data
 Moderately fast
Note
DT₅₀ range 12hrs to 39hrs, temp dependent
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7
Value
- - -
Note
-
Water-sediment DT₅₀ (days)
- - -
Water phase only DT₅₀ (days)
- - -
Soil adsorption and mobility
Property
Value
Source; quality score; and other information
Interpretation
Linear
Kd
-
R4 R = Peer reviewed scientific publications
4 = Verified data
 Non-mobile
Koc
14150
Notes and range
Koc range 12600-15700 mL g⁻¹
Freundlich
Kf
- - -
Kfoc
-
1/n
-
Notes and range
-
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
-0.31 Calculated Low leachability
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)
29.5
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
Rat		 High
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)
315
R3 R = Peer reviewed scientific publications
3 = Unverified data of known source
Eisenia foetida 28 day		 Moderate
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)
12
R4 R = Peer reviewed scientific publications
4 = Verified data
 Moderate
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
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
3.0
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
Oncorhynchus mykiss		 Moderate
Fish - Chronic 21 day NOEC (mg l⁻¹)
- - -
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)
0.000025
R4 R = Peer reviewed scientific publications
4 = Verified data
Daphnia magna		 High
Aquatic invertebrates - Chronic 21 day NOEC (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 - Acute 7 day EC₅₀, biomass (mg l⁻¹)
- - -
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)
- - -
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)
< 0.001
R3 R = Peer reviewed scientific publications
3 = Unverified data of known source
Chlorella pyrenoidosa 14 day		 High
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)
29.5
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
Rat		 High
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)
660
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
Rat		 -
Mammals - Inhalation LC₅₀ (mg l⁻¹)
- - -
Other Mammal toxicity endpoints
Intraperitoneal LD₅₀ = 55 mg kg⁻¹
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID )
3 = Unverified data of known source
Rat		 -
Intravenous TDLo = 0.571 mg kg⁻¹
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID )
3 = Unverified data of known source
Human		 -
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
May be absorbed through the skin
Mammalian dose elimination route and rate
Ivermectin excreted in faeces of treated cattle with little metabolism
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
;
E3 E = Unspecified genotoxicity type (miscellaneous data source)
3 = Negative
XNo, known not to cause a problem
Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant
?Possibly, status not identified
 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 swollen lymph glands, dizziness, hypotension, fever and myalgia
Posible liver 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
ivermectin
French
ivermectine
German
-
Danish
-
Italian
-
Spanish
ivermectino
Greek
-
Polish
-
Swedish
-
Hungarian
-
Dutch
-
Norwegian
-
Record last updated: 31/08/2023
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