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Chemical Datasheet

CHLORPYRIFOS

6.1 - Poison
Chemical Identifiers | Hazards | Response Recommendations | Physical Properties | Regulatory Information | Alternate Chemical Names

Chemical Identifiers

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
  • 2921-88-2
  • Poison
NIOSH Pocket Guide International Chem Safety Card
Chlorpyrifosexternal_link
NFPA 704
data unavailable
General Description
Chlorpyrifos is a white crystalline or irregularly flaked solid. It has a very faint mercaptan-type odor. It is not soluble in water. It can cause slight irritation to the eye and skin.

Hazards

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
Insoluble in water. It reacts with water and most reactive hydrogen compounds. The rate of hydrolysis in water increases with pH, with temperature and with the presence of copper and possibly other metals that can form chelates. (NTP, 1992)
Fire Hazard
Excerpt from ERG Guide 152 [Substances - Toxic (Combustible)]:

Combustible material: may burn but does not ignite readily. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form. (ERG, 2020)
Health Hazard
Symptoms of organophosphate insecticide poisoning: cholinesterase inhibition, headache, fatiguedizziness, blurred vision, weakness, nausea, cramps, diarrhea, chest discomfort, sweating, miosis, tearing, salivation, vomiting, cyanosis, papilledema, and muscle twitching. In advanced cases convulsions, coma, loss of reflexes, and loss of sphincter control may occur. EYES: Can produce mild to moderate eye irritation and transient corneal injury. SKIN: Undiluted liquid products can cause skin irritation. Prolonged or repeated exposure may cause superficial burns. (USCG, 1999)
Reactivity Profile
CHLORPYRIFOS is sensitive to heat and is decomposed by moisture. This chemical is hydrolyzed by strong alkalis. It is corrosive to copper and brass. It is also corrosive to copper alloys. It reacts with water and most reactive hydrogen compounds. The rate of hydrolysis in water increases with pH, with temperature and with the presence of copper and possibly other metals that can form chelates. (NTP, 1992)
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 absorbent listed below. More info about absorbents, including situations to watch out for...

Response Recommendations

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)
Firefighting
Excerpt from ERG Guide 152 [Substances - Toxic (Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Water spray, fog or regular foam. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal. Avoid aiming straight or solid streams directly onto the product.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from ERG Guide 152 [Substances - Toxic (Combustible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Cover with plastic sheet to prevent spreading. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Chlorpyrifosexternal link:

Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.

Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.

Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.

Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises. (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

Physical Properties

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.
Chemical Formula:
  • C9H11Cl3NO3PS
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: 108 to 110°F (NTP, 1992)
Vapor Pressure: 1.87e-05 mmHg at 77°F (NTP, 1992)
Vapor Density (Relative to Air): 12.09 (calculated) (NTP, 1992) - Heavier than air; will sink
Specific Gravity: 1.4 (Liquid at 110°F) (NIOSH, 2023) - Denser than water; will sink
Boiling Point: 320°F at 760 mmHg (Decomposes) (NIOSH, 2023)
Molecular Weight: 350.59 (NTP, 1992)
Water Solubility: approximately 2 mg/L at 77°F (NTP, 1992)
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
Chlorpyrifos; (Dursban) (2921-88-2) 0.6 mg/m3 15 mg/m3 44 mg/m3
(DOE, 2018)

Regulatory Information

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
Chlorpyrifos 2921-88-2 1 pound

(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.

Alternate Chemical Names

This section provides a listing of alternate names for this chemical, including trade names and synonyms.