DIMETHYL CHLOROTHIOPHOSPHATE
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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
Colorless to light amber liquid. Used as a chemical intermediate for insecticides, pesticides, and fungicides; oil and gasoline additives; plasticizers; corrosion inhibitors; flame retardants; and flotation agents. Not registered as a pesticide in the U.S. (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
This material may burn but does not ignite readily. This material may ignite combustibles (wood, paper, oil, etc.). When heated it emits very toxic fumes of chlorine containing compounds, phosphorus oxides, and sulfur oxides. (EPA, 1998)
Health Hazard
This material is a strong irritant to the eyes, skin, and mucous membranes. (EPA, 1998)
Reactivity Profile
Organothiophosphates, such as DIMETHYL CHLOROTHIOPHOSPHATE, 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
Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below. More info about absorbents, including situations to watch out for...
- Cellulose-Based Absorbents
- Mineral-Based & Clay-Based Absorbents
- Dirt/Earth
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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 156 [Substances - Toxic and/or Corrosive (Combustible / Water-Sensitive)]:
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
Wear positive pressure breathing apparatus and special protective clothing. Move container from fire area if you can do so without risk. Cool containers that are exposed to flames with water from the side until well after fire is out.
May react violently with water. Extinguish with dry chemical, carbon dioxide, water spray, fog, or foam. (EPA, 1998)
May react violently with water. Extinguish with dry chemical, carbon dioxide, water spray, fog, or foam. (EPA, 1998)
Non-Fire Response
Caution : Avoid sources of heat including fire. Dimethyl phosphorochloridothioate will liberate toxic phosphorus and sulfur oxides when heated to decomposition.
Avoid inhalation. Use water spray to reduce vapors. Do not touch spilled material; stop leak if you can do so without risk. Apply powdered limestone, slaked lime, soda ash, or sodium bicarbonate.
Small spills: absorb with sand or other noncombustible absorbent material and place into containers for later disposal.
Large spills: dike spill for later disposal. (EPA, 1998)
Avoid inhalation. Use water spray to reduce vapors. Do not touch spilled material; stop leak if you can do so without risk. Apply powdered limestone, slaked lime, soda ash, or sodium bicarbonate.
Small spills: absorb with sand or other noncombustible absorbent material and place into containers for later disposal.
Large spills: dike 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: Methyl PCT is extremely corrosive. Caution is advised.
Note: Methyl PCT is a cholinesterase inhibitor.
Signs and Symptoms of Acute Dimethyl Phosphorochloridothioate (Methyl PCT) Exposure: Acute exposure to Methyl PCT 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 either decrease following oral exposure or increase following dermal exposure. Hypotension (low blood pressure) may occur, although hypertension (high blood pressure) is not uncommon. Chest pain may be noted. Respiratory symptoms include dyspnea (shortness of breath), respiratory depression, and respiratory paralysis. Psychosis may occur. Contact with the skin, eyes, or mucous membranes may result in severe irritation, burns, and pain.
Emergency Life-Support Procedures: Acute exposure to Methyl PCT 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 Methyl PCT.
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 Methyl PCT.
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. Give the victims water or milk: children up to 1 year old, 125 mL (4 oz or 1/2 cup); children 1 to 12 years old, 200 mL (6 oz or 3/4 cup); adults, 250 mL (8 oz or 1 cup). Water or milk should be given only if victims are conscious and alert.
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: Methyl PCT is a cholinesterase inhibitor.
Signs and Symptoms of Acute Dimethyl Phosphorochloridothioate (Methyl PCT) Exposure: Acute exposure to Methyl PCT 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 either decrease following oral exposure or increase following dermal exposure. Hypotension (low blood pressure) may occur, although hypertension (high blood pressure) is not uncommon. Chest pain may be noted. Respiratory symptoms include dyspnea (shortness of breath), respiratory depression, and respiratory paralysis. Psychosis may occur. Contact with the skin, eyes, or mucous membranes may result in severe irritation, burns, and pain.
Emergency Life-Support Procedures: Acute exposure to Methyl PCT 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 Methyl PCT.
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 Methyl PCT.
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. Give the victims water or milk: children up to 1 year old, 125 mL (4 oz or 1/2 cup); children 1 to 12 years old, 200 mL (6 oz or 3/4 cup); adults, 250 mL (8 oz or 1 cup). Water or milk should be given only if victims are conscious and alert.
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)
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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:
1.32
at 77°F
(EPA, 1998)
- Denser than water; will sink
Boiling Point:
151 to 153°F
at 16 mmHg
(EPA, 1998)
Molecular Weight:
160.56
(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 |
|---|---|---|---|
| Dimethyl phosphorochloridothioate (2524-03-0) | 0.29 mg/m3 | 3.2 mg/m3 | 15 mg/m3 |
(DOE, 2018)
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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 |
|---|---|---|---|---|---|---|---|
| Dimethyl chlorothiophosphate | 2524-03-0 | 500 pounds | 500 pounds | 313 | |||
| Dimethyl phosphorochloridothioate | 2524-03-0 | 500 pounds | 500 pounds | X |
- "X" indicates that this is a second name for an EPCRA section 313 chemical already included on this consolidated list. May also indicate that the same chemical with the same CAS number appears on another list with a different chemical name.
(EPA List of Lists, 2022)
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.
- CHLORODIMETHOXYPHOSPHINE SULFIDE
- DIMETHOXY THIOPHOSPHONYL CHLORIDE
- DIMETHYL CHLOROPHOSPHOROTHIOATE
- DIMETHYL CHLOROTHIONOPHOSPHATE
- DIMETHYL CHLOROTHIOPHOSPHATE
- DIMETHYL PHOSPHOROCHLORIDOTHIOATE
- DIMETHYL THIONOPHOSPHOROCHLORIDATE
- DIMETHYL THIOPHOSPHOROCHLORIDATE
- METHYL PCT
- METHYL PHOSPHOROCHLORIDOTHIOATE ((MEO)2CLPS)
- O,O-DIMETHYL CHLOROPHOSPHOROTHIOATE
- O,O-DIMETHYL CHLOROTHIONOPHOSPHATE
- O,O-DIMETHYL CHLOROTHIOPHOSPHATE
- O,O-DIMETHYL PHOSPHOROCHLORIDOTHIOATE
- O,O-DIMETHYL PHOSPHOROCHLOROTHIOATE
- O,O-DIMETHYL PHOSPHOROTHIONOCHLORIDATE
- O,O-DIMETHYL THIONOPHOSPHOROCHLORIDATE
- O,O-DIMETHYL THIOPHOSPHORIC ACID CHLORIDE
- O,O-DIMETHYL THIOPHOSPHORYL CHLORIDE
- O,O-DIMETHYLPHOSPHOROCHLORIDOTHIOATE
- O,O-DIMETHYLTHIONOPHOSPHORYL CHLORIDE
- PHOSPHONOTHIOIC ACID, CHLORO-, O,O-DIMETHYL ESTER
- PHOSPHOROCHLORIDOTHIOIC ACID, O,O-DIMETHYL ESTER
Version 3.0.0