Monolinuron is a herbicide that is not widely approved for use in the developed world. It has a low to moderate mammalian oral toxicity. It is highly soluble in water and many organic solvents, and is volatile. Monolinuron has a high leaching potential and studies suggest that it is moderately persistent in soils. It is moderately toxic to birds, fish, aquatic invertebrates, aquatic plants and earthworms. It is relatively less toxic to honeybees.
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: GUS: High leachability
Selective, systemic absorbed by roots and leaves and translocated. Inhibition of photosynthesis at photosystem II
CAS RN
1746-81-2
EC number
217-129-5
CIPAC number
169
US EPA chemical code
207500
PubChem CID
15629
Molecular mass
214.65
PIN (Preferred Identification Name)
-
IUPAC name
3-(4-chlorophenyl)-1-methoxy-1-methylurea
CAS name
N'-(4-chlorophenyl)-N-methoxy-N-methylurea
Other status information
Chemical subject to PIC regulations
Relevant Environmental Water Quality Standards
-
Herbicide Resistance Class (HRAC MoA class)
C2
Herbicide Resistance Class (WSSA MoA class)
7
Insecticide Resistance Class (IRAC MoA class)
Not applicable
Fungicide Resistance Class (FRAC MOA class)
Not applicable
Examples of recorded resistance
-
Physical state
Colourless crystals
Formulations
Property
Value
Example manufacturers & suppliers of products using this active now or historically
Bayer CropScience
Hoechst
Example products using this active
Gramonol
Aresin
Monamex
Formulation and application details
Usually supplied as an emulsifiable concentrate or wettable powder.
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
735
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
High
Solubility - In organic solvents at 20 °C (mg l⁻¹)
200000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Acetone
-
3900
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Hexane
-
200000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Methanol
-
200000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Toluene
-
Melting point (°C)
81.5
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Boiling point (°C)
-
-
-
Degradation point (°C)
-
-
-
Flashpoint (°C)
-
-
-
Octanol-water partition coefficient at pH 7, 20 °C
P
1.58 X 1002
Calculated
-
Log P
2.2
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Low
Fat solubility of residues
Solubility
-
-
-
Data type
-
-
-
Density (g ml⁻¹)
1.5
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
-
Dissociation constant pKa) at 25 °C
Not applicable
A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes
-
No dissociation
Vapour pressure at 20 °C (mPa)
0.0064
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
3.80 X 10-04
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data
Non-volatile
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)
-
-
-
Degradation
Property
Value
Source; quality score; and other information
Interpretation
General biodegradability
-
Soil degradation (days) (aerobic)
DT₅₀ (typical)
60
DW4 DW = Don Wauchope personal database for Pka data: Wauchope, R. D. and Edwards, J. Dissociation constants for pesticide active ingredients: a database and comparison with predicted values. Dataset is no longer available. 4 = Verified data
Moderately persistent
DT₅₀ (lab at 20 °C)
50
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Moderately persistent
DT₅₀ (field)
-
-
-
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
General literature DT₅₀ range 33-66 days (R3)
Dissipation rate RL₅₀ (days) on plant matrix
Value
-
-
-
Note
-
Dissipation rate RL₅₀ (days) on and in plant matrix
Value
-
-
-
Note
-
Aqueous photolysis DT₅₀ (days) at pH 7
Value
-
-
-
Note
-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7
Value
Stable
C2 C = AGRITOX dataset. Dataset is no longer available. 2 = Unverified data of unknown source
Stable
Note
-
Water-sediment DT₅₀ (days)
22
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Fast
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)
-
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data
Moderately mobile
Koc (mL g⁻¹)
200
Notes and range
Best available data
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
2.89
Calculated
High leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
2.58 X 10-01
Calculated
-
Note
-
Potential for particle bound transport index
Medium
Calculated
-
Potential for loss via drain flow
Moderately mobile
Calculated
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
-
-
-
Bio-concentration factor
BCF (l kg⁻¹)
40
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
Whole fish
Low potential
CT₅₀ (days)
Not available
-
Known metabolites
None
ECOTOXICOLOGY
Terrestrial ecotoxicology
Property
Value
Source; quality score; and other information
Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)
2100
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Rat
Low
Mammals - Short term dietary NOEL
(mg kg⁻¹)
5
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Rat
High
(ppm diet)
50
-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Birds - Acute LD₅₀ (mg kg⁻¹)
1690
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Coturnix japonica
Moderate
Birds - Short term dietary (LC₅₀/LD₅₀)
-
-
-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)
1000
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Eisenia foetida
Moderate
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)
296
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Low
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)
Moderately harmful
AA2 AA = IOBC Database on classification of side effects to beneficial organisms, 2005 2 = Unverified data of unknown source
Chrysoperla carnea
-
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)
42
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Oncorhynchus mykiss
Moderate
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)
5
P3 P = Other non-EU, UK or US Governments and Regulators 3 = Unverified data of known source
Unknown species
Moderate
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
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
Chironomus riparius 1 day
Low
Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)
Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)
2.4
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
Lemna gibba
Moderate
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)
0.001
B1 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 1 = Estimated data with little or no verification
Scenedesmus subspicatus
High
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)
-
-
-
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)
2100
B5 B = UK CRD and ACP Evaluation Documents / and other DEFRA (UK) documents; Also Chemicals Regulation Division, Health and Safety Executive (HSE), UK (click here ) 5 = Verified data used for regulatory purposes
Rat
Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)
2000
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
-
Mammals - Inhalation LC₅₀ (mg l⁻¹)
3.39
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
-
Other Mammal toxicity endpoints
-
-
-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)
0.003
A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes
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