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clopyralid
** clopyralid-olamine ** Dowco 290 ** clopyralid acid ** 3,6-dichloropicolinic acid ** DCP ** Translations

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SUMMARY

A herbicide currently approved for use in the EU. It has a high aqueous solubility, is volatile and, based on its chemical properties, there is a high risk of it leaching to groundwater. It can be persistent in both soil and water systems depending upon conditions. It has a low mammalian toxicity and is not expected to bioaccumulate. It is an irritant. It is moderately toxic to birds, fish, aquatic invertebrates, honeybees and earthworms. It has a low toxicity to aquatic plants and algae.

GENERAL INFORMATION Click here for an explantaion of the general chemical status information
for clopyralid

Description: A herbicide for a post-emergence control of many broad-leaved weeds in a range of crops

Example pests controlled: Broadleaved weeds generally; Capeweed; Volunteer peas; Thistles; Prickly lettuce; Knapweed; Volunteer vetch; Cape ivy

Example applications: Cereals including wheat, barley, oats, triticale; Turf; Ornamentals; Non-cropped and fallow land; Industrial situations

Efficacy & activity: Research supports the effectiveness of clopyralid to control a wide range of broadleaved weeds

Availability status: Current

Introduction & key dates: 1977, France

EC Regulation 1107/2009 (repealing 91/414):
Status Approved
Dossier rapporteur/co-rapporteur Finland/Poland
Date inclusion expires 30/04/2020
EU Candidate for substitution (CfS) No
Listed in EU database Yes

Approved for use () or known to be used () in the following European countries: Click to access a note on the approvals information on this site

AT

BE

BG

CY

CZ

DE

DK

EE

EL

ES

FI

FR

HR

HU

IE

IT

LT

LU

LV

MT

NL

PL

PT

RO

SE

SI

SK

UK

Also used in: Australia, USA

Chemical structure: Click here for further information on the general chemical status information used on this site
Isomerism -
Chemical formula C6H3Cl2NO2
Canonical SMILES C1=CC(=NC(=C1Cl)C(=O)O)Cl
Isomeric SMILES No data
International Chemical Identifier key (InChIKey) HUBANNPOLNYSAD-UHFFFAOYSA-N
International Chemical Identifier (InChI) InChI=1S/C6H3Cl2NO2/c7-3-1-2-4(8)9-5(3)6(10)11/h1-2H,(H,10,11)
2D structure diagram/image available? Yes

General status: Click here for further information on the general chemical status information used on this site
Pesticide type Herbicide
Substance group Pyridine compound
Minimum active substance purity 950 g/kg
Known relevant impurities EU dossier - None declared
Substance origin Synthetic
Mode of action Selective, systemic, absorbed through leaves and roots. Synthetic auxin.
CAS RN 1702-17-6
EC number 216-935-4
CIPAC number 455
US EPA chemical code 117401
PubChem CID 15553
Molecular mass (g mol-1) 192.0
PIN (Preferred Identification Name) 3,6-dichloropyridine-2-carboxylic acid
IUPAC name 3,6-dichloropyridine-2-carboxylic acid
CAS name 3,6-dichloro-2-pyridinecarboxylic acid
Other status information PAN Listed as Highly Hazardous Chemical; Potential groundwater contaminant
Relevant Environmental Water Quality Standards -
Herbicide Resistance Classification (HRAC) O
Herbicide Resistance Classification (WSSA) 4
Insecticide Resistance Classification (IRAC) Not applicable
Fungicide Resistance Classification (FRAC) Not applicable
Examples of recorded resistance -
Physical state Cream to white coloured crystals
Related substances & organisms

Formulations:
Property Click here for information on the general product and branding information used on this site Value
Example manufacturers & suppliers of products using this active now or historically
  • AgriGuard
  • Dow AgroSciences
  • Teliton
Example products using this active
  • Esteem
  • Galera
  • Grazon 90
  • Stinger
  • Lontrel
  • Dowco 290
UK LERAP status None
Formulation and application details Usually supplied as a soluble concentrate, wettable powder or emulsifiable concentrate.


ENVIRONMENTAL FATE

for clopyralid

Property Click here for information on the parameters used to describe environmental fate on this site Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with fate data Interpretation Click here for information on the way in which we interpret environmental fate data
Solubility - In water at 20oC (mg l-1) 7850 A5 High
Solubility - In organic solvents at 20oC (mg l-1) 250000 A5 - Acetone -
102000 A5 - Ethyl acetate -
4600 A5 - Xylene -
6000 A5 - n-Hexane -
Melting point (oC) 149.6 A5 -
Boiling point (oC) Decomposes before boiling A5 -
Degradation point (oC) 164 A5 -
Flashpoint (oC) Not expected to self ignite; Not highly flammable A5 -
Octanol-water partition coefficient at pH 7, 20oC P 2.34 X 10-03 Calculated -
Log P -2.63 A5 Low
Bulk density (g ml-1)/Specific gravity 1.76 A5 -
Dissociation constant (pKa) at 25oC 2.01 A5 -
Note: Strong acid
Vapour pressure at 20oC (mPa) 1.36 X 10-09 A5 Low volatility
Henry's law constant at 25oC (Pa m3 mol-1) 1.80 X 10-11 A5 Non-volatile
GUS leaching potential index Click here for a note on the limitations of the GUS index 4.51 Calculated High leachability
SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate Click here for a note on the limitations of the SCI-GROW index Value 1.04 X 10+00 Calculated -
Note -
Potential for particle bound transport index Click here for a note on the limitations of the potential for particle bound transport index - Calculated Low
Maximum UV-vis absorption L mol-1 cm-1 Neutral solution: Maxima at 220nm, 280nm : 22100nm, 9200nm & 4790nm; [Acidic solution: Maxima at 202nm, 225nm, 281nm : 16200nm, 8890nm & 3800nm; [Basic solution: Maxima at 220nm, 279nm : 9300nm, 5030nm A5 -
Surface tension (mN m-1) 71.5 A5 at 20 oC -

Degradation:
Property Click here for information on the parameters used to describe substance degradation Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with degradation data Interpretation Click here for information on the way in which we interpret substance degradation data
General biodegradability Not readily biodegradable
Soil degradation (days) (aerobic) DT50 (typical) 23.2 A5 Non-persistent
DT50 (lab at 20oC) 23.2 A5 Non-persistent
DT50 (field) 8.2 A5 Non-persistent
DT90 (lab at 20oC) 82.6 A5 -
DT90 (field) 49.5 A5 -
DT50 modelling endpoint 23.7 A5 representative of field studies -
Note EU 2017 dossier lab studies DT50 range 4.9-64.6 days, DT90 range 16.2-214.6 days, Soils=10; field studies DT50 range 2.0-13.5 days, DT90 range 12.1-78.7 days; Other sources: DT50 40 days (R3)
Dissipation rate RL50 on plant matrix Value - - -
Note -
Dissipation rate RL50 on and in plant matrix Value 5.4 R4 -
Note Published literature RL50 range 4.3-6.7 days, 3 field crops, various matrices, n=3
Aqueous photolysis DT50 (days) at pH 7 Value 271 A5 Stable
Note Not significant degradation route
Aqueous hydrolysis DT50 (days) at 20oC and pH 7 Value Stable A5 -
Note Stable pH 4 to pH 9, 50 degC
Water-sediment DT50 (days) - - -
Water phase only DT50 (days) 148 A5 Stable

Soil adsorption and mobility:
Property Click here for information on the parameters used to describe substance adsorption and mobility Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with adsorption and mobility data Interpretation Click here for information on the way in which we interpret substance adsorption and mobility
Linear Kd 0.071 A5 Very mobile
Koc 5.0
Notes and range EU dossier Kd range 0.032-0.151, Koc range 3.43-7.34 mL/g, Soils=5
Freundlich Kf - - -
Kfoc -
1/n -
Notes and range -
pH sensitivity Limited evidence of decreasing adsorption with increasing pH


ECOTOXICOLOGY

for clopyralid

Property Click here for information on the parameters used to describe substance ecotoxicology Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with ecotoxicology data Interpretation Click here for information on the way in which we interpret substance ecotoxicology
Bio-concentration factor BCF (l kg-1) 1 A5 Lepomis macrochirus Low potential
CT50 (days) 0.1 -
Mammals - Acute oral LD50 (mg kg-1) > 5000 A5 Rat Low
Mammals - Short term dietary NOEL (mg kg-1) > 15 L2 Rat, 2 year High
(ppm diet) > 150 -
Birds - Acute LD50 (mg kg-1) 1465 A5 Anas platyrhynchos Moderate
Birds - Short term dietary (LC50/LD50) > 1033 mg kg bw-1 day-1 A5 Colinus virginianus -
Fish - Acute 96 hour LC50 (mg l-1) > 99.9 A5 Oncorhynchus mykiss Moderate
Fish - Chronic 21 day NOEC (mg l-1) 10.8 A4 Pimephales promelas Low
Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) > 99 A5 Daphnia magna Moderate
Aquatic invertebrates - Chronic 21 day NOEC (mg l-1) 17 A5 Daphnia magna Low
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) 50.0 A5 Chironomus riparius Low
Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg-1) - - -
Aquatic plants - Acute 7 day EC50, biomass (mg l-1) 89 A5 Lemna gibba Low
Non-target plants - - -
- - -
Algae - Acute 72 hour EC50, growth (mg l-1) 30.5 A5 Raphidocelis subcapitata Low
Algae - Chronic 96 hour NOEC, growth (mg l-1) 17 Q1 Unknown species Low
Honeybees Contact acute 48 hour LD50 (μg bee-1) > 98.1 A5 Apis mellifera Moderate
Oral acute 48 hour LD50 (μg bee-1) > 100 A5 Apis mellifera Low
Unknown mode acute 48 hour LD50 (μg bee-1) - - -
Earthworms - Acute 14 day LC50 (mg kg-1) > 1000 A5 Eisenia foetida Low
Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1) >= 1.97 A5 Eisenia foetida Moderate
Other soil macro-organisms - e.g. Collembola LR50 / EC50 / NOEC / % Effect - - -
Other arthropod (1) LR50 g ha-1 2000 as mL/ha
A5 Aphidius rhopalosiphi
-
% Effect 0
90
Mortality
Fecundity
Dose: 0.2 kg ha-1
A5 Aphidius rhopalosiphi, adult
-
Other arthropod (2) LR50 g ha-1 2000 as mL/ha
A5 Typhlodromus pyri
-
% Effect 5.9
27.7
Mortality
Fecundity
Dose: 0.2 kg ha-1
A5 Typhlodromus pyri, protonymph
-
Soil micro-organisms Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect
A5
Dose: 5 x field rate
-
Mesocosm study data NOEAEC mg l-1 - - -
NOEAEC mg l-1 - - -


HUMAN HEALTH AND PROTECTION

for clopyralid

General:
Property Click here for information on the parameters used to describe human health and protection issues Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with human health and protection data Interpretation Click here for information on the way in which we interpret human health and protection data
Threshold of Toxicological Concern (Cramer Class) Click here for a note on the limitations of the Cramer class High (class III) - -
Mammals - Acute oral LD50 (mg kg-1) > 5000 A5 Rat Low
Mammals - Dermal LD50 (mg kg-1 body weight) > 5000 A5 Rat -
Mammals - Inhalation LC50 (mg l-1) > 1.0 A5 Rat (nose only) -
Other Mammal toxicity endpoints - -
ADI - Acceptable Daily Intake (mg kg-1bw day-1) 0.15 A5 Rat, SF=100 -
ARfD - Acute Reference Dose (mg kg-1bw day-1) None allocated A5 -
AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) - - -
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) 0.15 A5 -
Dermal penetration studies (%) 25-75 A5 concentration dependent -
Dangerous Substances Directive 76/464 - - -
Exposure Limits - - -
Exposure Routes Public Minimal risk of dietary exposure
Occupational Risk of exposure acceptable under label recommendations for use for personal protection clothing and equipment
European MRLs Click here for the EU MRL pesticide database
Drinking Water Standards - - -
Drinking Water MAC (μg l-1) - - -

Health issues:
Carcinogen Mutagen Endocrine disrupter Reproduction / development effects Cholinesterase inhibitor Neurotoxicant

Respiratory tract irritant Skin irritant Skin sensitiser Eye irritant Phototoxicant

-

-

General human health issues Possible liver and kidney toxicant

: Yes, known to cause a problem
: No, known not to cause a problem
: Possibly, status not identified
- : No data found

Handling issues:
Property Click here for information on the parameters used to describe substance handling issues Value Source/Quality Score/Other Information Click here for information on the primary data sources used to populate this database with data on handling issues Interpretation Click here for information on the way in which we interpret data on handling issues
General Click here for a description of the International Maritime Dangerous Goods (IMDG) codes Prevent release of dust
Not explosive or oxidising
CLP classification 2013 Health: H318
EC Risk Classification Click here to view information omn the EU risk phrases Xn - Harmful: R41
EC Safety Classification Click here to view information omn the EU safety phrases S2, S26, S39
WHO Classification III - Slightly hazardous
US EPA Classification (formulation) IV - Caution - Not acutely toxic
UN Number Usually 3077
Waste disposal & packaging Click here for a description of UN packaging marks Packaging Group III (minor danger)


TRANSLATIONS

for clopyralid

Language Name
English clopyralid
French clopyralid
German Clopyralid
Danish clopyralid
Italian clopiralid
Spanish clopiralida
Greek clopyralid
Slovenian klopiralid
Polish chlopyralid
Swedish klopyralid
Hungarian klopiralid
Dutch clopyralid

Record last updated: Wednesday 03 April 2019
Contact: aeru@herts.ac.uk
© University of Hertfordshire