DEMETON-S-METHYL
![](javascript:dropDownText("section1_info","section1_info_marker","/static/images/up_arrow.png","/static/images/down_arrow.png")){kind=icon}
![](javascript:dropDownText("sec1_help","sec1_help_marker","/static/images/dropdown_opened.gif","/static/images/dropdown_closed.gif"))
The
Chemical Identifier fields
include common identification numbers, the
NFPA diamond
U.S. Department of Transportation hazard labels, and a general
description of the chemical. The information in CAMEO Chemicals comes
from a variety of
data sources.
| CAS Number | UN/NA Number |
|---|---|
|
|
| DOT Hazard Label | USCG CHRIS Code |
|
none |
| NIOSH Pocket Guide | International Chem Safety Card |
| none |
NFPA 704
data unavailable
General Description
Pale yellow oil. Used as an insecticide. Not registered as a pesticide in the U.S. (EPA, 1998)
![](javascript:dropDownText("section2_info","section2_info_marker","/static/images/up_arrow.png","/static/images/down_arrow.png")){kind=icon}
![](javascript:dropDownText("sec2_help","sec2_help_marker","/static/images/dropdown_opened.gif","/static/images/dropdown_closed.gif"))
The
Hazard fields
include
special hazard alerts
air and water
reactions, fire hazards, health hazards, a reactivity profile, and
details about
reactive groups assignments
and
potentially incompatible absorbents.
The information in CAMEO Chemicals comes from a variety of
data sources.
Reactivity Alerts
none
Air & Water Reactions
No rapid reaction with air. No rapid reaction with water.
Fire Hazard
When heated to decomposition, it emits very toxic fumes of oxides of phosphorus and sulfur. This compound is a liquid organophosphorus insecticide. This material may burn but does not ignite readily. Container may explode in heat of fire. Fire may produce irritating or poisonous gases. Runoff from fire control water may give off poisonous gases. Hydrolyzed by alkali. (EPA, 1998)
Health Hazard
It inhibits the nervous system and is absorbed readily through the skin. This compound is a liquid organophosphorus insecticide. Poisonous; may be fatal if inhaled, swallowed or absorbed through skin. Contact may cause burns to skin and eyes. (EPA, 1998)
Reactivity Profile
Organophosphates, such as DEMETON-S-METHYL, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents
No information available.
![](javascript:dropDownText("section3_info","section3_info_marker","/static/images/up_arrow.png","/static/images/down_arrow.png")){kind=icon}
![](javascript:dropDownText("sec3_help","sec3_help_marker","/static/images/dropdown_opened.gif","/static/images/dropdown_closed.gif"))
The
Response Recommendation fields
include isolation and evacuation distances, as well as recommendations for
firefighting, non-fire response, protective clothing, and first aid. The
information in CAMEO Chemicals comes from a variety of
data sources.
Isolation and Evacuation
Excerpt from ERG Guide 152 [Substances - Toxic (Combustible)]:
IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.
SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.
FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.
SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.
FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
This compound is a liquid organophosphorus insecticide. Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. Wear positive pressure breathing apparatus and special protective clothing. Remove and isolate contaminated clothing at the site.
Small fires: dry chemical, carbon dioxide, water spray, or foam. Large fires: water spray, fog or foam. Move container from fire area if you can do so without risk. Fight fire from maximum distance. Dike fire control water for later disposal; do not scatter the material. (EPA, 1998)
Small fires: dry chemical, carbon dioxide, water spray, or foam. Large fires: water spray, fog or foam. Move container from fire area if you can do so without risk. Fight fire from maximum distance. Dike fire control water for later disposal; do not scatter the material. (EPA, 1998)
Non-Fire Response
This compound is a liquid organophosphorus insecticide. Do not touch spilled material; stop leak if you can do so without risk. Use water spray to reduce vapors.
Small spills: absorb with sand or other noncombustible absorbent material and place into containers for later disposal.
Large spills: dike far ahead of spill for later disposal. (EPA, 1998)
Small spills: absorb with sand or other noncombustible absorbent material and place into containers for later disposal.
Large spills: dike far ahead of spill for later disposal. (EPA, 1998)
Protective Clothing
For emergency situations, wear a positive pressure, pressure-demand, full facepiece self-contained breathing apparatus (SCBA) or pressure- demand supplied air respirator with escape SCBA and a fully-encapsulating, chemical resistant suit. (EPA, 1998)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Warning: Demeton-s-methyl is readily absorbed through the skin.
Note: Demeton-s-methyl is a cholinesterase inhibitor.
Signs and Symptoms of Acute Demeton-S-Methyl Exposure: Acute exposure to demeton-S-methyl may produce the following signs and symptoms: pinpoint pupils, blurred vision, headache, dizziness, muscle spasms, and profound weakness. Vomiting, diarrhea, abdominal pain, seizures, and coma may also occur. The heart rate may decrease following oral exposure or increase following dermal exposure. Hypotension (low blood pressure) is not uncommon. Respiratory symptoms include dyspnea (shortness of breath), respiratory depression, and respiratory paralysis. Psychosis may occur.
Emergency Life-Support Procedures: Acute exposure to demeton-S-methyl may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.
Inhalation Exposure:
1. Move victims to fresh air. Emergency personnel should avoid self-exposure to demeton-S-methyl.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Transport to a health care facility.
Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self- exposure to demeton-S-methyl.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Remove contaminated clothing as soon as possible.
4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
5. Wash exposed skin areas three times with soap and water.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Transport to a health care facility.
Ingestion Exposure:
1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
2. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
3. Vomiting may be induced with syrup of Ipecac. If elapsed time since ingestion of demeton-s-methyl is unknown or suspected to be greater than 30 minutes, do not induce vomiting and proceed to Step
4.Ipecac should not be administered to children under 6 months of age.Warning: Ingestion of demeton-s-methyl may result in sudden onset of seizures or loss of consciousness. Syrup of Ipecac should be administered only if victims are alert, have an active gag-reflex, and show no signs of impending seizure or coma. If ANY uncertainty exists, proceed to Step
4.The following dosages of Ipecac are recommended: children up to 1 year old, 10 mL (1/3 oz); children 1 to 12 years old, 15 mL (1/2 oz); adults, 30 mL (1 oz). Ambulate (walk) the victims and give large quantities of water. If vomiting has not occurred after 15 minutes, Ipecac may be readministered. Continue to ambulate and give water to the victims. If vomiting has not occurred within 15 minutes after second administration of Ipecac, administer activated charcoal.
4. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.
5. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults.
6. Transport to a health care facility. (EPA, 1998)
Note: Demeton-s-methyl is a cholinesterase inhibitor.
Signs and Symptoms of Acute Demeton-S-Methyl Exposure: Acute exposure to demeton-S-methyl may produce the following signs and symptoms: pinpoint pupils, blurred vision, headache, dizziness, muscle spasms, and profound weakness. Vomiting, diarrhea, abdominal pain, seizures, and coma may also occur. The heart rate may decrease following oral exposure or increase following dermal exposure. Hypotension (low blood pressure) is not uncommon. Respiratory symptoms include dyspnea (shortness of breath), respiratory depression, and respiratory paralysis. Psychosis may occur.
Emergency Life-Support Procedures: Acute exposure to demeton-S-methyl may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.
Inhalation Exposure:
1. Move victims to fresh air. Emergency personnel should avoid self-exposure to demeton-S-methyl.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Transport to a health care facility.
Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self- exposure to demeton-S-methyl.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Remove contaminated clothing as soon as possible.
4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
5. Wash exposed skin areas three times with soap and water.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Transport to a health care facility.
Ingestion Exposure:
1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
2. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
3. Vomiting may be induced with syrup of Ipecac. If elapsed time since ingestion of demeton-s-methyl is unknown or suspected to be greater than 30 minutes, do not induce vomiting and proceed to Step
4.Ipecac should not be administered to children under 6 months of age.Warning: Ingestion of demeton-s-methyl may result in sudden onset of seizures or loss of consciousness. Syrup of Ipecac should be administered only if victims are alert, have an active gag-reflex, and show no signs of impending seizure or coma. If ANY uncertainty exists, proceed to Step
4.The following dosages of Ipecac are recommended: children up to 1 year old, 10 mL (1/3 oz); children 1 to 12 years old, 15 mL (1/2 oz); adults, 30 mL (1 oz). Ambulate (walk) the victims and give large quantities of water. If vomiting has not occurred after 15 minutes, Ipecac may be readministered. Continue to ambulate and give water to the victims. If vomiting has not occurred within 15 minutes after second administration of Ipecac, administer activated charcoal.
4. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.
5. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults.
6. Transport to a health care facility. (EPA, 1998)
![](javascript:dropDownText("section4_info","section4_info_marker","/static/images/up_arrow.png","/static/images/down_arrow.png")){kind=icon}
![](javascript:dropDownText("sec4_help","sec4_help_marker","/static/images/dropdown_opened.gif","/static/images/dropdown_closed.gif"))
The
Physical Property fields
include properties such as vapor pressure and
boiling point, as well as explosive limits and
toxic exposure thresholds
The information in CAMEO Chemicals comes from a variety of
data sources.
Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
| Chemical Formula: |
|
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: data unavailable
Vapor Pressure:
0.00036 mmHg
at 68°F
(EPA, 1998)
Vapor Density (Relative to Air): data unavailable
Specific Gravity:
1.207
at 68°F
(EPA, 1998)
- Denser than water; will sink
Boiling Point:
192°F
at 0.15 mmHg
(EPA, 1998)
Molecular Weight:
230.3
(EPA, 1998)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: data unavailable
AEGLs (Acute Exposure Guideline Levels)
No AEGL information available.ERPGs (Emergency Response Planning Guidelines)
No ERPG information available.PACs (Protective Action Criteria)
| Chemical | PAC-1 | PAC-2 | PAC-3 |
|---|---|---|---|
| Demeton-S-methyl (919-86-8) | 0.45 mg/m3 | 5 mg/m3 | 22 mg/m3 |
(DOE, 2018)
![](javascript:dropDownText("section5_info","section5_info_marker","/static/images/up_arrow.png","/static/images/down_arrow.png")){kind=icon}
![](javascript:dropDownText("sec5_help","sec5_help_marker","/static/images/dropdown_opened.gif","/static/images/dropdown_closed.gif"))
The
Regulatory Information fields
include information from
the U.S. Environmental Protection Agency's Title III Consolidated List of
Lists,
the U.S. Cybersecurity and Infrastructure Security Agency's Chemical Facility
Anti-Terrorism Standards,
and the U.S. Occupational Safety and Health Administration's
Process Safety Management of Highly Hazardous Chemicals Standard List
(see more about these
data sources).
EPA Consolidated List of Lists
| Regulatory Name | CAS Number/ 313 Category Code |
EPCRA 302 EHS TPQ |
EPCRA 304 EHS RQ |
CERCLA RQ | EPCRA 313 TRI |
RCRA Code |
CAA 112(r) RMP TQ |
|---|---|---|---|---|---|---|---|
| Demeton-S-methyl | 919-86-8 | 500 pounds | 500 pounds |
(EPA List of Lists, 2022)
CISA Chemical Facility Anti-Terrorism Standards (CFATS)
No regulatory information available.OSHA Process Safety Management (PSM) Standard List
No regulatory information available.![](javascript:dropDownText("section6_info","section6_info_marker","/static/images/up_arrow.png","/static/images/down_arrow.png")){kind=icon}
![](javascript:dropDownText("sec6_help","sec6_help_marker","/static/images/dropdown_opened.gif","/static/images/dropdown_closed.gif"))
This section provides a listing of alternate names for this chemical,
including trade names and synonyms.
- BAY 18436
- BAYER 25/154
- DEMETON-S-METHYL
- DIMETHYL S-(2-ETHTHIOETHYL) THIOPHOSPHATE
- ETHANETHIOL, 2-(ETHYLTHIO)-, S-ESTER WITH O,O-DIMETHYL PHOSPHOROTHIOATE
- ISOMETASYSTOX
- ISOMETHYLSYSTOX
- METAISOSEPTOX
- METAISOSYSTOX
- METASYSTOX 55
- METASYSTOX FORTE
- METASYSTOX I
- METASYSTOX J
- METASYSTOX(I)
- METHYL DEMETON THIOESTER
- METHYL ISOSYSTOX
- METHYL-MERCAPTOFOS TEOLOVY
- METHYLTHIONODEMETON
- O,O-DIMETHYL 2-ETHYLMERCAPTOETHYL THIOPHOSPHATE, THIOLO ISOMER
- O,O-DIMETHYL S-(2-(ETHYLTHIO)ETHYL) PHOSPHOROTHIOATE
- O,O-DIMETHYL S-(2-ETHTHIOETHYL) PHOSPHOROTHIOATE
- O,O-DIMETHYL S-(ETHYLMERCAPTO)ETHYL THIOPHOSPHATE
- O,O-DIMETHYL S-2-(ETHYLTHIO)ETHYL PHOSPHOROTHIOATE
- PHOSPHOROTHIOIC ACID, O,O-DIMETHYL S-(2-(ETHYLTHIO)ETHYL) ESTER
- PHOSPHOROTHIOIC ACID, S-(2-(ETHYLTHIO)ETHYL) O,O-DIMETHYL ESTER
- S-(2-(ETHYLTHIO)ETHYL) DIMETHYL PHOSPHOROTHIOLATE
- S-(2-(ETHYLTHIO)ETHYL) O,O-DIMETHYL PHOSPHOROTHIOATE
- S-(2-(ETHYLTHIO)ETHYL) O,O-DIMETHYL THIOPHOSPHATE
- S-[2-(ETHYLTHIO)ETHYL] O,O-DIMETHYL PHOSPHOROTHIOATE
- S-[2-(ETHYLTHIO)ETHYL] O,O-DIMETHYL THIOPHOSPHATE
- THIOMETON OXON
Version 3.0.0