Substance profile
Methomyl
Methomyl is a white crystalline solid with a slightly sulfurous odor.
01 · Identification
What Methomyl is
Methomyl is a white crystalline solid with a slightly sulfurous odor. It boils at 335 °C, melts at 77.8 °C.
Under the GHS it carries the signal word Danger.
Other names for Methomyl
- methomyl (ISO)
- 1-(methylthio)ethylideneamino N-methylcarbamate
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H300 | Fatal if swallowed. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic to aquatic life with long lasting effects. |
Precautionary statements: P270, P273, P301, P310, P330, P391, P501
03 · Physical and chemical properties
Methomyl properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 335 °C (635 °F) | at 760 mmHg | DOE PAC |
| Melting point | 77.78 °C (172 °F) | NIOSH | |
| 78 °C (172.4 °F) | ICSC | ||
| Density | 1.3 g/cm³ | ICSC | |
| 1.2946 g/cm³ | at 23.89 °C | CAMEO | |
| 1.2946 g/cm³ | at 24 °C | HSDB | |
| Solubility | SOL IN MOST ORG SOLVENTS | HSDB | |
| Sol at 25 °C in wt/wt percent: water 5.8; ethanol 42; methanol 100; isopropanol 22; acetone 73 | at 25 °C | HSDB | |
| In water, 58,000 mg/l @ 25 °C | at 25 °C | HSDB | |
| Vapor pressure | 0.0000054 mmHg | at 25 °C | HSDB |
| 0.00005 mmHg | at 25 °C | NIOSH | |
| Lower explosive limit (LEL) | Noncombustible Solid, but may be dissolved in flammable liquids. | NIOSH | |
| Corrosivity | AQ SOLN NONCORROSIVE | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Methomyl
Storage conditions
Keep /liq formulations/ away from heat, sparks, & open flame. Do not subject liquid to temperatures below 32 °F.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Strong bases.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
METHOMYL is a carbamate ester. Carbamates are chemically similar to, but more reactive than amides. Like amides they form polymers such as polyurethane resins. Carbamates are incompatible with strong acids and bases, and especially incompatible with strong reducing agents such as hydrides. Flammable gaseous hydrogen is produced by the combination of active metals or nitrides with carbamates. Strongly oxidizing acids, peroxides, and hydroperoxides are incompatible with carbamates.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Methomyl in the storage compatibility matrix →