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. These hazard alerts do not take account of usage patterns or exposure, thus do not represent risk.
Human health Moderate alert: Mammals acute toxicity: Moderate; Endocrine disrupter
Warning: Significant data are missing
GENERAL INFORMATION
Description
A pre- and post-emergence herbicide used in a wide range of crops
Example pests controlled
Chickweed; Red shank; Knotgrass; Barnyardgrass
Example applications
Rice; Vegetables including carrots, celeriac and celery; Tomatoes; Ornamentals; Herbs including fennel and parsley
Efficacy & activity
-
GB regulatory status
GB COPR regulatory status
Not approved
Date COPR inclusion expires
Expired
GB LERAP status
No UK approval for use as a plant protection agent
EC Regulation 1107/2009 (repealing 91/414)
EC Regulation 1107/2009 status
Not approved
Dossier rapporteur/co-rapporteur
Not applicable
Date EC 1107/2009 inclusion expires
Expired
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
Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries
ISIceland
NONorway
Additional information
Also used in
-
Chemical structure
Isomerism
Pentanochlor exhibits stereoisomerism, specifically optical isomerism, due to the presence of a chiral centre at the 2-position of the pentanamide side chain. This chiral carbon is bonded to four distinct groups, allowing for the existence of two enantiomers. Commercial formulations of pentanochlor are typically racemic mixtures, containing equal proportions of both enantiomers,
Selective with contact action. Photosynthetic electron transport inhibitor at the photosystem II.
CAS RN
2307-68-8
EC number
218-988-9
CIPAC number
317
US EPA chemical code
020901
PubChem CID
16826
CLP index number
No data found
Molecular mass
239.7
PIN (Preferred Identification Name)
-
IUPAC name
(RS)-3'-chloro-2-methylvaler-p-toluidide
CAS name
N-(3-chloro-4-methylphenyl)-2-methylpentanamide
Forever chemical
-
Other status information
-
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 solid
Commercial
Property
Value
Availability status
Unknown
Introduction & key dates
1960, first reported
Example manufacturers & suppliers of products using this active now or historically
Certis
NUfarm UK
FMC
Example products using this active
Croptex bronze
Atlas brown
Solan
Dakuron
Formulation and application details
Usually suppled as an emulsifiable concentrate
Commercial production
The production of pentanochlor typically involves the acylation of a substituted aniline, specifically 3-chloro-4-methylaniline, with 2-methylpentanoic acid or its activated derivative such as an acid chloride. This reaction forms the amide bond central to pentanochlor’s structure, yielding N-(3-chloro-4-methylphenyl)-2-methylpentanamide. The process is carried out under controlled conditions using an organic solvent and a base to neutralise the byproduct (usually HCl if an acid chloride is used). After the reaction, the crude product is purified through recrystallisation or chromatography to achieve the desired purity for agricultural use.
Impact on climate of production and use
Data for the amount of life cycle GHGs produced by pentanochlor are not available in the public domain. However, whilst estimates vary, more general data suggests that between 18 and 27 kilograms of CO₂e is emitted per kilogram of herbicide produced.
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
8.5
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)
250000
L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source
Xylene
-
Melting point (°C)
85.5
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
2.04 X 1004
Calculated
-
Log P
4.31
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
High
Fat solubility of residues
Solubility
-
-
-
Data type
-
-
-
Density (g ml⁻¹)
1.11
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Dissociation constant pKa) at 25 °C
-
-
-
-
Vapour pressure at 20 °C (mPa)
0.3
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
at 25 °C
Low volatility. If applied directly to plants, drift is a concern & mitigation is advisable
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
1.59 X 10-03
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
at 25 °C
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)
4
S1 S = Expert judgement 1 = Estimated data with little or no verification
Non-persistent
DT₅₀ (lab at 20 °C)
-
-
-
DT₅₀ (field)
-
-
-
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
Best available data
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
-
-
-
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)
-
G3 G = Extension Toxicology network database EXTOXNET. Available online but no longer updated. (click here ) 3 = Unverified data of known source
Mobile
Koc (mL g⁻¹)
30
Notes and range
-
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
1.52
Calculated
Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
3.50 X 10-03
Calculated
-
Note
-
Potential for particle bound transport index
Low
Calculated
-
Potential for loss via drain flow
Mobile
Calculated
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
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
Environmental fate
Warning:
Ecotoxicity
