PHOSPHOROTHIOIC ACID, O,O-DIMETHYL S-(2-(METHYLTHIO) ETHYL) ESTER
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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 | none |
NFPA 704
data unavailable
General Description
A straw-colored liquid. Used as a systemic insecticide and acaricide effective against sucking insects. (EPA, 1998)
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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
(Non-Specific -- Organophosphorus pesticide, liquid, n.o.s.) 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. (EPA, 1998)
Health Hazard
(Non-specific -- Organophosphorus pesticide, liquid) May be fatal if inhaled, swallowed or absorbed through the skin. Contact may cause burns to skin and eyes. (Non-specific -- Organophosphate insecticide) May cause respiratory failure. (EPA, 1998)
Reactivity Profile
PHOSPHOROTHIOIC ACID, O,O-DIMETHYL S-(2-(METHYLTHIO) ETHYL) ESTER, like other thiophosphate esters, may react with strong reducing agents such as hydrides to give highly toxic and flammable phosphine gas. 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.
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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 171 [Substances (Low to Moderate Hazard)]:
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 tank car or highway tank 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, 2024)
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 tank car or highway tank 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, 2024)
Firefighting
(Non-Specific -- Organophosphorus pesticide, liquid, n.o.s.) 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.
(Non-Specific -- Organophosphorus pesticide, liquid, n.o.s.) 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-Specific -- Organophosphorus pesticide, liquid, n.o.s.) 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
(Non-Specific -- Organophosphorus pesticide, liquid) 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.
Small dry spills: with clean shovel place material into clean, dry container and cover; move containers from spill area.
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.
Small dry spills: with clean shovel place material into clean, dry container and cover; move containers from spill area.
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: Extremely toxic by all routes of exposure. Effects may be delayed up to 12 hours. Caution is advised.
Note: Demephion-S is a cholinesterase inhibitor.
Signs and Symptoms of Demephion-S Exposure: Acute exposure to Demephion-S may produce the following signs and symptoms: sweating, pinpoint pupils, blurred vision, headache, dizziness, profound weakness, muscle spasms, seizures, and coma. Mental confusion and psychosis may occur. Excessive salivation, nausea, vomiting, anorexia, diarrhea, and abdominal pain may also occur. The heart rate may decrease following oral exposure or increase following dermal exposure. Chest pain may be noted. Hypotension (low blood pressure) may be observed, although hypertension (high blood pressure) is not uncommon. Respiratory symptoms include dyspnea (shortness of breath), pulmonary edema, respiratory depression, and respiratory paralysis.
Emergency Life-Support Procedures: Acute exposure to Demephion-S 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 Demephion-S.
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 100% humidified 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. Rush to a health care facility.
Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self-exposure to Demephion-S.
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 100% humidified 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. Speed in removing material from the skin is of extreme importance.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Rush 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 100% humidified oxygen or other respiratory support.
2. DO NOT induce vomiting.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
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. Rush to a health care facility. (EPA, 1998)
Note: Demephion-S is a cholinesterase inhibitor.
Signs and Symptoms of Demephion-S Exposure: Acute exposure to Demephion-S may produce the following signs and symptoms: sweating, pinpoint pupils, blurred vision, headache, dizziness, profound weakness, muscle spasms, seizures, and coma. Mental confusion and psychosis may occur. Excessive salivation, nausea, vomiting, anorexia, diarrhea, and abdominal pain may also occur. The heart rate may decrease following oral exposure or increase following dermal exposure. Chest pain may be noted. Hypotension (low blood pressure) may be observed, although hypertension (high blood pressure) is not uncommon. Respiratory symptoms include dyspnea (shortness of breath), pulmonary edema, respiratory depression, and respiratory paralysis.
Emergency Life-Support Procedures: Acute exposure to Demephion-S 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 Demephion-S.
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 100% humidified 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. Rush to a health care facility.
Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self-exposure to Demephion-S.
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 100% humidified 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. Speed in removing material from the skin is of extreme importance.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Rush 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 100% humidified oxygen or other respiratory support.
2. DO NOT induce vomiting.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
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. Rush to a health care facility. (EPA, 1998)
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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: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity:
1.218
at 77°F
(EPA, 1998)
- Denser than water; will sink
Boiling Point:
149°F
at 0.1 mmHg
decomposes
(EPA, 1998)
Molecular Weight:
216.27
(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 |
|---|---|---|---|
| Methyl demeton methyl; (Phosphorothioic acid, O,O-dimethyl-S-(2-methylthio)ethyl ester) (2587-90-8) | 1.8 mg/m3 | 20 mg/m3 | 120 mg/m3 |
(DOE, 2024)
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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 |
|---|---|---|---|---|---|---|---|
| Phosphorothioic acid, O,O-dimethyl-5-(2-(methylthio)ethyl)ester | 2587-90-8 | 500 pounds | 500 pounds |
(EPA List of Lists, 2024)
CISA Chemical Facility Anti-Terrorism Standards (CFATS)
No regulatory information available.OSHA Process Safety Management (PSM) Standard List
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This section provides a listing of alternate names for this chemical,
including trade names and synonyms.
- CEBETOX
- CYMETOX
- DEMEPHION
- DEMEPHION-S
- ETHANETHIOL, 2-(METHYLTHIO)-, O,O-DIMETHYL PHOSPHOROTHIOATE
- ETHANETHIOL, 2-(METHYLTHIO)-, S-ESTER WITH O,O-DIMETHYL PHOSPHOROTHIOATE
- ISONITOX
- ISOTINOX
- METHYL DEMETON METHYL
- 2-METHYLTHIOETHYL O,O-DIMETHYL PHOSPHOROTHIOATE
- PHOSPHOROTHIOIC ACID,
- PHOSPHOROTHIOIC ACID, O,O-DIMETHYL S-(2-(METHYLTHIO) ETHYL) ESTER
- TINOX
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