Dichlorprop is a post-emergence, selective herbicide. It has a moderate aqueous solubility and is volatile. Its data suggests it is not persistent in soils but may persist in some water systems. It is moderately toxic to. Dichlorprop has a moderate to low toxicity to most aquatic organisms.
Hazard 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. These hazard alerts do not take account of usage patterns or exposure, thus do not represent risk.
Cereals including wheat, barley; Non-crop situations including right-of-way, commercial and industrial sites
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)
Not applicable
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
Dichlorprop exhibits optical isomerism due to the presence of a single chiral centre in its molecular structure, making it a chiral molecule. This results in two enantiomers: the R- and S-forms. Originally, dichlorprop was marketed as a racemic mixture, containing equal amounts of both enantiomers. However, only the R-enantiomer, known as dichlorprop-p, is biologically active as a herbicide and so often used alone.
Example manufacturers & suppliers of products using this active now or historically
Headland Agrochemicals
FBC
Bayer
Universal Crop Protection
Example products using this active
Weedone 170
Hedonal DP
Hormatox
Polyclene
Seritox
Polymore
Formulation and application details
Often supplied as an emulsifiable concentrate or as an emulsion.
Commercial production
The commercial production of dichlorprop involves synthesising its active chiral acid form, (R)-2-(2,4-dichlorophenoxy)propanoic acid, through a controlled chemical process. Initially, 2,4-dichlorophenol is reacted with propylene oxide or a similar alkylating agent to form the phenoxypropanoic acid backbone. This intermediate is then resolved or synthesised asymmetrically to yield the R-enantiomer, known as dichlorprop-p, which is the biologically active form.
Impact on climate of production and use
-
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
350
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data
Moderate
Solubility - In organic solvents at 20 °C (mg l⁻¹)
689000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Ethyl acetate
-
1265000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Acetone
-
3030
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Hexane
-
61200
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Toluene
-
Melting point (°C)
117
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)
204
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
(open cup)
-
Octanol-water partition coefficient at pH 7, 20 °C
P
1.95 X 1002
Calculated
-
Log P
2.29
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data
Low
Fat solubility of residues
Solubility
-
-
-
Data type
-
-
-
Density (g ml⁻¹)
1.42
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Dissociation constant pKa) at 25 °C
3
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Strong acid
Vapour pressure at 20 °C (mPa)
0.01
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data
Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
8.80 X 10-06
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)
10
W4 W = French database provided by ARVALIS-Institut du Végétal. Dataset no longer available. 4 = Verified data
Non-persistent
DT₅₀ (lab at 20 °C)
14
Y4 Y = Germany's Federal Environment Agency (UBA) (click here ) 4 = Verified data
Non-persistent
DT₅₀ (field)
10
X3 X = WINPST database (click here ) 3 = Unverified data of known source
Non-persistent
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
Other sources: DT₅₀ 21-25 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
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Stable
Note
-
Water-sediment DT₅₀ (days)
12
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)
-
-
-
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)
-
Q4 Q = Miscellaneous data from online sources 4 = Verified data
Mobile
Koc (mL g⁻¹)
74
Notes and range
Other sources: 12.0-170 mL g⁻¹ (R3)
Freundlich
Kf (mL g⁻¹)
0.77
R4 R = Peer reviewed scientific publications 4 = Verified data
Mobile
Kfoc (mL g⁻¹)
41.2
1/n
0.87
Notes and range
Kf range 0.67-0.86 mL g⁻¹, Kfoc range 34.4-47.9 mL g⁻¹, 1/n range 0.86-0.88, Soils=2
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
2.39
Calculated
Transition state
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
5.07 X 10-02
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
-
-
-
Bio-concentration factor
BCF (l kg⁻¹)
6
Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
Moderate
Mammals - Short term dietary NOEL
(mg kg⁻¹)
-
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
-
(ppm diet)
> 5
-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Birds - Acute LD₅₀ (mg kg⁻¹)
504
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
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
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
Vegetative vigour ER₅₀ (g ha⁻¹)
-
-
-
Seedling emergence ER₅₀ (g ha⁻¹)
-
-
-
Honeybees (Apis spp.)
Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
16
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Moderate
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)
> 0.5
J4 J = Pesticide Action Network database (click here ) 4 = Verified data
Oncorhynchus mykiss
Moderate
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)
-
-
-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
0.22
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
Low risk to Europeans as no longer approved for use
Occupational
Low risk to Europeans as no longer approved for use
MRLs
European
EU MRL pesticide database
Great Britain
GB MRL Register
Notes
-
Drinking Water Standards
Non-statutory WHO drinking water guideline 0.1 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
UK EA QS database 2018
-
Drinking Water MAC (μg l⁻¹)
-
-
-
Mammalian dose elimination route and rate
-
-
-
Health issues
Specific human health issues
Carcinogen
Genotoxic
Endocrine disruptor
No data found
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
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
Ecotoxicity
Warning:
