Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 240-815-0 | CAS number: 16752-77-5
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
![](https://chesar.echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_toxicological-information.png)
Toxicological Summary
- Administrative data
- Workers - Hazard via inhalation route
- Workers - Hazard via dermal route
- Workers - Hazard for the eyes
- Additional information - workers
- General Population - Hazard via inhalation route
- General Population - Hazard via dermal route
- General Population - Hazard via oral route
- General Population - Hazard for the eyes
- Additional information - General Population
Administrative data
Workers - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.11 mg/m³
- Most sensitive endpoint:
- acute toxicity
- Route of original study:
- By inhalation
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 12.5
- Dose descriptor starting point:
- NOAEC
- Value:
- 5.6 mg/m³
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 1.4 mg/m³
- Explanation for the modification of the dose descriptor starting point:
An acute rat inhalation study (3 hours exposure time) that includes dose response relationships for relevant sub-lethal effects (cholinesterase inhibition) has been identified and a relevant NOAEC has been set.In general, methomyl’s effects are primarily acute in nature and are related to the inhibition of cholinesterase which occurs quickly and reverses rapidly following either oral or inhalation exposure. From the battery of studies (both short-term and long-term) conducted on methomyl the most sensitive adverse endpoint is cholinesterase inhibition and therefore the acute inhalation study selected should be relevant for assessing long-term inhalation systemic effects without the need for assessment factors for duration extrapolation. Within the EFSA Scientific Review Report, 2006, 83, 1-73, (Conclusion on the peer review of methomyl), a NOAEL from an acute study was considered as an appropriate basis upon which to derive longer term reference values such as the ADI and systemic AOEL with only the need to use uncertainty factors for inter and intra species variation.
The NOAEC in the acute inhalation study was selected based on % brain cholinesterase inhibition observed in an acute inhalation study conducted in rats. In this study brain cholinesterase inhibition was more sensitive than RBC inhibition and a NOAEC of 5.6 mg/m3was derived. In the study rats were exposed for 3 hours. For worker assessment, the inhalatory NOAEC rat needs to be corrected for the difference between respiratory rates under standard conditions and under conditions of light activity. With the assumption that inhalation absorption of methomyl in the rat is equal to inhalation absorption in humans the following calculation is conducted:
Corrected NOAEC = 5.6 mg/m3* (3 h/d / 8h/d)*(6.7m3/10m3)
= 1.4 mg/m3
- AF for dose response relationship:
- 1
- Justification:
- A factor of 1 is appropriate since the dose descriptor is a NOAEC
- AF for differences in duration of exposure:
- 1
- Justification:
- see reasoning above
- AF for interspecies differences (allometric scaling):
- 2.5
- Justification:
- or differences not related to allometric scaling
- AF for intraspecies differences:
- 5
- Justification:
- effects for workers
- AF for the quality of the whole database:
- 1
- Justification:
- A factor of 1 is appropriate because the database is adequately robust.
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.3 mg/m³
- Most sensitive endpoint:
- acute toxicity
- Route of original study:
- By inhalation
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 12.5
- Dose descriptor starting point:
- NOAEC
- Value:
- 5.6 mg/m³
- Modified dose descriptor starting point:
- NOAEC
- Value:
- 3.8 mg/m³
- Explanation for the modification of the dose descriptor starting point:
An acute rat inhalation study (3 hours exposure time) that includes dose response relationships for relevant sub-lethal effects (cholinesterase inhibition) has been identified and a relevant NOAEC of 5.6 mg/m3has been set based on % brain cholinesterase inhibition. For worker assessment, the inhalatory NOAEC rat needs to be corrected for the difference between respiratory rates under standard conditions and under conditions of light activity. The study duration of 3 hours maybe conservative in derive the acute DNEL. With the assumption that inhalation absorption of methomyl in the rat is equal to inhalation absorption in humans the following calculation is conducted:
Corrected NOAEC = 5.6 mg/m3* (6.7m3/10m3)
= 3.8 mg/m3
- AF for dose response relationship:
- 1
- Justification:
- A factor of 1 is appropriate since the dose descriptor is a NOAEC
- AF for interspecies differences (allometric scaling):
- 2.5
- Justification:
- for differences not related to allometric scaling
- AF for intraspecies differences:
- 5
- Justification:
- effects for workers
- AF for the quality of the whole database:
- 1
- Justification:
- A factor of 1 is appropriate because the database is considered to be adequately robust
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Workers - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.5 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
- Route of original study:
- Dermal
DNEL related information
- DNEL derivation method:
- ECHA REACH Guidance
- Overall assessment factor (AF):
- 180
- Dose descriptor starting point:
- NOAEL
- Value:
- 90 mg/kg bw/day
- AF for dose response relationship:
- 1
- Justification:
- A factor of 1 is appropriate since the dose descriptor is a NOAEC
- AF for differences in duration of exposure:
- 6
- Justification:
- A factor of 6 is appropriate to extrapolate from a sub-acute to chronic
- AF for interspecies differences (allometric scaling):
- 2.4
- Justification:
- for allometric scaling related to rabbit.
- AF for other interspecies differences:
- 2.5
- Justification:
- for differences not related to allometric scaling
- AF for intraspecies differences:
- 5
- Justification:
- effects for workers
- AF for the quality of the whole database:
- 1
- Justification:
- A factor of 1 is appropriate because the database is considered to be adequately robust
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
Workers - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- low hazard (no threshold derived)
Additional information - workers
General Population - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
General Population - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
General Population - Hazard via oral route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- no hazard identified
Acute/short term exposure
- Hazard assessment conclusion:
- no hazard identified
DNEL related information
General Population - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- no hazard identified
Additional information - General Population
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
![ECHA](/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/echa_logo.png)