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Chemical Datasheet

PARATHION

 6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 56-38-2
  • 2783 (solid)
  • 3018 (liquid)
  • Poison
  • PTO
NIOSH Pocket Guide International Chem Safety Card
Parathion
  • PARATHION
NFPA 704
data unavailable
General Description
Parathion is a deep brown to yellow liquid with a faint odor of garlic. It is an organic phosphate insecticide which acts as an inhibitor of cholinesterase, and as such it is highly toxic by all routes of exposure. It may be found as a liquid or as a dry mixture where the liquid is absorbed onto a dry carrier.

Hazards

Reactivity Alerts
none
Air & Water Reactions
Slightly soluble in water.
Fire Hazard
When heated to decomposition, it can emit toxic fumes of oxides of nitrogen, phosphorus, and sulfur. High pressure hoses may scatter material from broken containers. Containers may explode when heated. Stable in distilled water and in acid solution. Store below 77-86F. It slowly decomposes in air and hydrolyzes in the presence of alkaline material. Containers may explode when heated. (EPA, 1998)
Health Hazard
This material is extremely toxic; the probable oral lethal dose is 5-50 mg/kg, or between 7 drops and 1 teaspoonful for a 150-lb. person. As little as 1 drop can endanger life if splashed in the eye. Toxicity is highest by inhalation. People at special risk are those with a history of glaucoma, cardiovascular disease, hepatic disease, renal disease, or central nervous system abnormalities. (EPA, 1998)
Reactivity Profile
Light-yellow liquid, it turns solid at 6°C, a deadly poison by all routes. Organic phosphate insecticide, acts as an inhibitor of cholinesterase. Violent reaction when used as solvent to dissolve endrin. When heated to decomposition it emits very toxic fumes of oxides of sulfur, phosphorus, and nitrogen [Lewis, 3rd ed., 1993, p. 984].
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.

Response Recommendations

Isolation and Evacuation
Excerpt from 152 Polymerizable warning [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
Use water spray to keep fire-exposed containers cool. If a leak or spill has not ignited, use water spray to disperse vapors and to provide protection for firefighters. Water spray may be used to flush spills away from exposures. Fight advanced or massive fires from a safe distance or from a protected location. Special protective clothing should be worn; normal protective clothing may be penetrated.

Use water spray, dry chemical, foam, or carbon dioxide. (EPA, 1998)
Non-Fire Response
In case of leaks or spills, special protective clothing should be worn. Use water spray to disperse vapors and flush spills away. Ventilate area of spill or leak. Spills may be absorbed in vermiculite, dry sand, earth, or a similar material. (EPA, 1998)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Parathion:

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.

Provide:
• EYEWASH - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection.
• QUICK DRENCH - Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.] (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Ethyl parathion 56-38-2 Liquid >480 >480 >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2023)

First Aid
CAUTION: Parathion is a cholinestorase inhibitor. It has been reported that as little as one drop of parathion can endanger life if splashed in the eye. Toxicity is highest by inhalation.

Signs and Symptoms of Acute Parathion Exposure: Acute exposure to parathion 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 parathion 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 parathion.
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 parathion.
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 parathion 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 parathion 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)

Physical Properties

Chemical Formula:
  • C10H14NO5PS
Flash Point: 248 to 320°F (EPA, 1998)
Lower Explosive Limit (LEL): Not highly flammable. (EPA, 1998)
Upper Explosive Limit (UEL): Not highly flammable. (EPA, 1998)
Autoignition Temperature: data unavailable
Melting Point: 43°F (EPA, 1998)
Vapor Pressure: 3.78e-05 mmHg at 68°F (EPA, 1998)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.26 (EPA, 1998) - Denser than water; will sink
Boiling Point: 707°F at 760 mmHg (EPA, 1998)
Molecular Weight: 291.27 (EPA, 1998)
Water Solubility: less than 1 mg/mL at 73°F (NTP, 1992)
Ionization Energy/Potential: data unavailable
IDLH: 10 mg/m3 (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

Interim AEGLs for Parathion (56-38-2)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes NR 2.8 mg/m3 3.6 mg/m3
30 minutes NR 1.9 mg/m3 2.5 mg/m3
60 minutes NR 1.5 mg/m3 2 mg/m3
4 hours NR 0.96 mg/m3 1.3 mg/m3
8 hours NR 0.48 mg/m3 0.63 mg/m3
NR = Not recommended due to insufficient data
(NAC/NRC, 2023)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Parathion (56-38-2) 0.15 mg/m3 1.5 mg/m3 2 mg/m3
(DOE, 2018)

Regulatory Information

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
Parathion 56-38-2 100 pounds 10 pounds 10 pounds 313 P089
Phosphorothioic acid, O,O-diethyl-O-(4-nitrophenyl) ester 56-38-2 100 pounds 10 pounds 10 pounds X P089

(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