| methoxychlor (Ref: OMS 466) |
 |
Environmental Fate - Ecotoxicology - Human Health
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Further data may be found in the VSDB
GENERAL INFORMATION 
for methoxychlor
Description: An insecticide effective against a wide range of pests encountered in agricultural (crops and livestock), horticulture and domestic situations
Example pests controlled: Flies, Mosquitoes; Cockroaches; Chiggers
Example applications: Liverstock pest control; Domestic gardens; Pet pest management
Efficacy & activity: -
Availability status: Current
Introduction & key dates: circa 1948
EC Regulation 1107/2009 (repealing 91/414):
| Status | Not approved |
| Dossier rapporteur/co-rapporteur | - |
| Date inclusion expires | Expired |
| EU Candidate for substitution (CfS) | - |
| Listed in EU database | Yes |
Approved for use (
) or known to be used (
) in the following European countries: 
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 |
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Also used in: USA
Chemical structure:
| Isomerism | A prochiral molecule |
| Chemical formula | C16H15Cl3O2 |
| Canonical SMILES | COC1=CC=C(C=C1)C(C2=CC=C(C=C2)OC)C(Cl)(Cl)Cl |
| Isomeric SMILES | No data |
| International Chemical Identifier key (InChIKey) | IAKOZHOLGAGEJT-UHFFFAOYSA-N |
| International Chemical Identifier (InChI) | InChI=1S/C16H15Cl3O2/c1-20-13-7-3-11(4-8-13)15(16(17,18)19)12-5-9-14(21-2)10-6-12/h3-10,15H,1-2H3 |
| 2D structure diagram/image available? | Yes |
Cambridge Crystallographic Data Centre diagrams:
| Common Name | Relationship | Link |
| Methoxychlor | - |  |
General status:
| Pesticide type | Insecticide, Veterinary substance | |||
| Substance group | Organochlorine | |||
| Minimum active substance purity | - | |||
| Known relevant impurities | - | |||
| Substance origin | Synthetic | |||
| Mode of action | Contact and stomach action. Central nervous stimulant, producing hyperactivity, convulsions and death. | |||
| CAS RN | 72-43-5 | |||
| EC number | 200-779-9 | |||
| CIPAC number | 14 | |||
| US EPA chemical code | 034001 | |||
| PubChem CID | 4115 | |||
| Molecular mass (g mol-1) | 345.65 | |||
| PIN (Preferred Identification Name) | - | |||
| IUPAC name | 1,1,1-trichloro-2,2-bis(4-methoxyphenyl)ethane | |||
| CAS name | 1,1'-(2,2,2-trichloroethylidene)bis(4-methoxybenzene) | |||
| Other status information | POP candidate; OSPAR pfa | |||
| Relevant Environmental Water Quality Standards | - | |||
| Herbicide Resistance Classification (HRAC) | Not applicable | |||
| Herbicide Resistance Classification (WSSA) | Not applicable | |||
| Insecticide Resistance Classification (IRAC) | 3B | |||
| Fungicide Resistance Classification (FRAC) | Not applicable | |||
| Examples of recorded resistance | Ctenocephalides felis Cydia pomonella Euxoa ochrogaster Haematobia irritans Helicoverpa zea many more |
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| Physical state | Colourless crystalline solid | |||
| Related substances & organisms | - | |||
Formulations:
| Property |
Value | |||
| Example manufacturers & suppliers of products using this active now or historically |
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| Example products using this active |
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| UK LERAP status | No UK approval for use as a pesticide under EC Regulation 1107/2009 | |||
| Formulation and application details | Supplied in a variety of formulations including emulsifiable concentrates, wettable powders, flowables, seed treatments and aerosols . | |||
ENVIRONMENTAL FATE
for methoxychlor
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Solubility - In water at 20oC (mg l-1) | 0.1 | G4 | Low | |
| Solubility - In organic solvents at 20oC (mg l-1) | 440000 | L3 - Xylene | - | |
| 50000 | L3 - Methanol | - | ||
| 700000 | V3 - Trichloroethane | - | ||
| 1333000 | V2 - Dichloromethane | - | ||
| Melting point (oC) | 87 | F3 | - | |
| Boiling point (oC) | - | - | - | |
| Degradation point (oC) | - | - | - | |
| Flashpoint (oC) | - | - | - | |
| Octanol-water partition coefficient at pH 7, 20oC | P | 6.76 X 1005 | Calculated | - |
| Log P | 5.83 | Q2 | High | |
| Bulk density (g ml-1)/Specific gravity | 1.41 | L3 | - | |
| Dissociation constant (pKa) at 25oC | - | - | - | |
| Note: | ||||
| Vapour pressure at 20oC (mPa) | 0.08 | Q2 | Low volatility | |
| Henry's law constant at 25oC (Pa m3 mol-1) | 2.00 X 10-02 | V3 | Non-volatile | |
GUS leaching potential index  |
-1.88 | Calculated | Low leachability | |
| SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate |
Value | 5.35 X 10-03 | Calculated | - |
| Note | Estimated concentrations of chemicals with Koc values greater than 9995 ml g-1 are beyond the scope of the regression data used in SCI-GROW development. If there are concerns for such chemicals, a higher tier groundwater exposure assessment should be considered, regardless of the concentration returned by SCI-GROW | |||
| Potential for particle bound transport index |
- | Calculated | High | |
| Maximum UV-vis absorption L mol-1 cm-1 | - | - | - | |
| Surface tension (mN m-1) | - | - | - | |
Degradation:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
General biodegradability | - |
| Soil degradation (days) (aerobic) | DT50 (typical) | 120 | G4 | Persistent |
| DT50 (lab at 20oC) | 120 | F3 | Persistent | |
| DT50 (field) | - | - | - | |
| DT90 (lab at 20oC) | - | - | - | |
| DT90 (field) | - | - | - | |
| DT50 modelling endpoint | - | - | - | |
| Note | Best available data | |||
| Dissipation rate RL50 on plant matrix | Value | 6.5 | R3 | - |
| Note | Cherry leaves, n=1 | |||
| Dissipation rate RL50 on and in plant matrix | Value | 1.8 | R3 | - |
| Note | Collard leaves, n=1 | |||
| Aqueous photolysis DT50 (days) at pH 7 | Value | - | - | - |
| Note | - | |||
| Aqueous hydrolysis DT50 (days) at 20oC and pH 7 | Value | - | - | - |
| Note | - | |||
| Water-sediment DT50 (days) | - | - | - | |
| Water phase only DT50 (days) | - | - | - | |
Soil adsorption and mobility:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Linear | Kd | - | G3 | Non-mobile |
| Koc | 80000 | |||
| Notes and range | Best available data | |||
| Freundlich | Kf | - | - | - |
| Kfoc | - | |||
| 1/n | - | |||
| Notes and range | - | |||
| pH sensitivity | - | |||
Key metabolites:
| Metabolite | Formation medium | Estimated maximum occurrence fraction | 1107/2009 relevancy |
|
| 1,1-(2,2-dichloroethylidene)bis(4-methoxybenzene) | Soil | - | - | |
ECOTOXICOLOGY
for methoxychlor
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Bio-concentration factor | BCF (l kg-1) | 1622 | E3 (Other literature values Log BCF range 2.8-4.1 (R3)) | Threshold for concern |
| CT50 (days) | Not available | - | ||
| Mammals - Acute oral LD50 (mg kg-1) | > 6000 | L3 Rat | Low | |
| Mammals - Short term dietary NOEL | (mg kg-1) | - | L2 Rat, 2 year | - |
| (ppm diet) | 200 | - | ||
| Birds - Acute LD50 (mg kg-1) | > 2000 | F4 Anas platyrhynchos | Low | |
| Birds - Short term dietary (LC50/LD50) | - | - | - | |
| Fish - Acute 96 hour LC50 (mg l-1) | 0.052 | L3 Oncorhynchus mykiss | High | |
| Fish - Chronic 21 day NOEC (mg l-1) | - | - | - | |
| Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) | 0.00078 | L3 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) | - | - | - | |
| Non-target plants | - | - | - | |
| - | - | - | ||
| Algae - Acute 72 hour EC50, growth (mg l-1) | 0.6 | F4 Scenedesmus quadricauda | Moderate | |
| Algae - Chronic 96 hour NOEC, growth (mg l-1) | - | - | - | |
| Honeybees (Apis spp.) | Contact acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | > 23.6 | F4 | 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) | - | - | - | |
| 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 pollinators (1) | Acute LD50 (worst case from 24 , 48 and 72 hour values - μg insect-1) | - | - | - |
| Mode of exposure | - | |||
| Other pollinators (2) | Acute LD50 (worst case from 24 , 48 and 72 hour values - μg insect-1) | - | - | - |
| Mode of exposure | - | |||
| Earthworms - Acute 14 day LC50 (mg kg-1) | - | - | - | |
| Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1) | - | - | - | |
| Other soil macro-organisms - e.g. Collembola | LR50 / EC50 / NOEC / % Effect | - | - | - |
| Other arthropod (1) | LR50 g ha-1 | - | - | - |
| % Effect | - | - | - | |
| Other arthropod (2) | LR50 g ha-1 | - | - | - |
| % Effect | - | - | - | |
| Soil micro-organisms | - | - | - | |
| Mesocosm study data | NOEAEC mg l-1 | - | - | - |
| NOEAEC mg l-1 | - | - | - | |
HUMAN HEALTH AND PROTECTION
for methoxychlor
General:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Threshold of Toxicological Concern (Cramer Class) |
High (class III) | - | - | |
| Mammals - Acute oral LD50 (mg kg-1) | > 6000 | L3 Rat | Low | |
| Mammals - Dermal LD50 (mg kg-1 body weight) | > 2000 | L3 Rabbit | - | |
| Mammals - Inhalation LC50 (mg l-1) | - | - | - | |
| Other Mammal toxicity endpoints | - | - | ||
| ADI - Acceptable Daily Intake (mg kg-1bw day-1) | 0.1 | JMPR 1977 | - | |
| ARfD - Acute Reference Dose (mg kg-1bw day-1) | - | - | - | |
| AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) | - | - | - | |
| AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) | - | - | - | |
| Dermal penetration studies (%) | - | - | - | |
| Dangerous Substances Directive 76/464 | List I; List II | - | - | |
| Exposure Routes | Public | - | ||
| Occupational | - | |||
| European MRLs | Click here for the EU MRL pesticide database | |||
| Drinking Water Standards | Non-statutory WHO drinking water guideline 0.02 mg/L | UK EA QS database, 2018 | - | |
| Drinking Water MAC (μg l-1) | - | - | - | |
Health issues:
| Carcinogen | Genotoxic | Endocrine disrupter | Reproduction / development effects | Cholinesterase inhibitor | Neurotoxicant | |||
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A3; B0; C0; D0; E3 |
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| Respiratory tract irritant | Skin irritant | Skin sensitiser | Eye irritant | Phototoxicant | ||||
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| General human health issues | Endocrine issues - Strong estrogenic effect Potential kidney & liver toxicant IARC Group 3 carcinogen |
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| Key: Genotoxicity A: Chromosome aberration (EFSA database) B: DNA damage/repair (EFSA database) C: Gene mutation (EFSA database) D: Genome mutation (EFSA database) E: Unspecified genotoxicity type (miscellaneous data source) 0: No data 1: Positive 2: Mixed/ambiguous results 3: Negative |
Key: Other : Yes, known to cause a problem  : No, known not to cause a problem  : Possibly, status not identified - : No data found |
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Handling issues:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| General |
Highly flammable and easily ignited by heat, sparks and flames | |||
| CLP classification 2013 | Health: H302, H312, H332, H351, H371 Environment: H400 |
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| EC Risk Classification |
Not classified: Obsolete | |||
| EC Safety Classification |
Not classified: Obsolete | |||
| WHO Classification | U | - | Unlikely to present an acute hazard | |
| UN Number | 2761 | |||
| Waste disposal & packaging |
- | |||
| Language | Name |
| English | methoxychlor |
| French | methoxychlore |
| German | Methoxychlor |
| Danish | methoxychlor |
| Italian | metossicloro |
| Spanish | metoxiclor |
| Greek | - |
| Slovenian | metoksiklor |
| Polish | metoksychlor |
| Swedish | - |
| Hungarian | - |
| Dutch | - |
Record last updated: Tuesday 02 July 2019
Contact: aeru@herts.ac.uk