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Chemical Datasheet

SODIUM CYANIDE

6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 143-33-9
  • 1689
  • Poison
  • SCN
NIOSH Pocket Guide International Chem Safety Card
Sodium cyanide (as CN)
  • SODIUM CYANIDE
NFPA 704
Diamond Hazard Value Description
0
3 0
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 0 Normally stable, even under fire conditions.
White Special
(NFPA, 2010)
General Description
A white crystalline solid, lump solid or powder. A deadly human poison by ingestion. Toxic by skin absorption through open wounds, by ingestion, and by inhalation of dust.

Hazards

Reactivity Alerts
Air & Water Reactions
Deliquescent. Soluble in water. Slowly decomposed by water and very rapidly by acids to give off hydrogen cyanide, a flammable poison gas.

Based on a scenario where the chemical is spilled into an excess of water (at least 5 fold excess of water), half of the maximum theoretical yield of Hydrogen Cyanide gas will be created in 12 minutes. Experimental details are in the following: "Development of the Table of Initial Isolation and Protective Distances for the 2008 Emergency Response Guidebook", ANL/DIS-09-2, D.F. Brown, H.M. Hartmann, W.A. Freeman, and W.D. Haney, Argonne National Laboratory, Argonne, Illinois, June 2009.
Fire Hazard
Sodium cyanide is not combustible itself, but contact with acids releases highly flammable hydrogen cyanide gas. Fire may produce irritating or poisonous gases. Runoff from fire control water may give off poisonous gases. Container may explode in the heat of fire. Avoid strong oxidizers such as nitrates and chlorates; acids and acid salts. Avoid contact with acids. Aqueous solutions rapidly decompose. (EPA, 1998)
Health Hazard
Super toxic; probable oral lethal dose in humans is less than 5 mg/kg or a taste (less than 7 drops) for a 70 kg (150 lb.) person. Sodium cyanide is poisonous and may be fatal if inhaled, swallowed or absorbed through the skin. Contact with sodium cyanide may cause burns to skin and eyes. Individuals with chronic diseases of the kidneys, respiratory tract, skin, or thyroid are at greater risk of developing toxic cyanide effects. (EPA, 1998)
Reactivity Profile
SODIUM CYANIDE produces deadly and flammable hydrogen cyanide gas pon contact with acids, even very weak acids , e.g., carbon dioxide dissolved in water (soda pop). Reacts violently with fluorine, magnesium, nitric acid, nitrates and nitrites [Sax, 9th ed., 1996, p. 2958]. Incompatible with strong oxidizing agents.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 157 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-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: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 1689 datasheet.

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
Full protective clothing including self-contained breathing apparatus, rubber gloves, boots, and bands around legs, arms, and waist should be provided. No skin surface should be exposed. Normal fire fighting procedures may be used.

Fight fire from maximum distance. Move container from area if you can do it without risk. Dike fire control water for later disposal. Do not scatter the material.

Use water. Use dry chemical, carbon dioxide, water spray, or foam for small fires, water spray, fog, or foam for large fires. (EPA, 1998)
Non-Fire Response
Excerpt from 157 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. A vapor-suppressing foam may be used to reduce vapors. DO NOT GET WATER INSIDE CONTAINERS. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Prevent entry into waterways, sewers, basements or confined areas.

SMALL SPILL: Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Sodium cyanide (as CN):

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
Sodium cyanide (45%) 143-33-9 Liquid >480 >480 >480 >480 >480
Sodium cyanide (sat) 143-33-9 Liquid >480 >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
Warning: Heart palpitations may occur within minutes after exposure. Caution is advised. Effects may be delayed.

Signs and Symptoms of Acute Sodium Cyanide Exposure: Signs and symptoms of acute exposure to sodium cyanide may include hypertension (high blood pressure) and tachycardia (rapid heart rate), followed by hypotension (low blood pressure) and bradycardia (slow heart rate). Cardiac arrhythmias and other cardiac abnormalities are common. Cyanosis (blue tint to the skin and mucous membranes) and cherry-red or bloody mucous membranes may occur. Tachypnea (rapid respiratory rate) may be followed by respiratory depression. Pulmonary edema and lung hemorrhage may also occur. Headache, vertigo (dizziness), agitation, and giddiness may be followed by combative behavior, dilated and unreactive pupils, convulsions, paralysis, and coma. Sodium cyanide is irritating to the skin and mucous membranes. Lacrimation (tearing) and a burning sensation of the mouth and throat are common. Increased salivation, nausea, and vomiting are often seen.

Emergency Life-Support Procedures: Acute exposure to sodium cyanide may require decontamination and life support for the victims. All exposed persons should be transported to a health care facility as quickly as possible. 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 sodium cyanide.
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. IMMEDIATELY begin administering 100% oxygen to all victims. Monitor victims for respiratory distress.Warning: To prevent self-poisoning, avoid mouth-to-mouth breathing; use a forced-oxygen mask. Direct oral contact with sodium cyanide-contaminated persons or their gastric contents may result in self-poisoning.
3. RUSH to a health care facility!
4. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self- exposure to sodium cyanide.
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. IMMEDIATELY begin administering 100% oxygen to all victims. Monitor victims for respiratory distress.Warning: To prevent self-poisoning, avoid mouth-to-mouth breathing; use a forced-oxygen mask. Direct oral contact with sodium cyanide-contaminated persons or their gastric contents may result in self-poisoning.
3. RUSH to a health care facility!
4. Remove contaminated clothing as soon as possible.
5. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
6. Wash exposed skin areas twice with soap and water.
7. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

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. IMMEDIATELY begin administering 100% oxygen to all victims. Monitor victims for respiratory distress.Warning: To prevent self-poisoning, avoid mouth-to-mouth breathing; use a forced-oxygen mask. Direct oral contact with sodium cyanide-contaminated persons or their gastric contents may result in self-poisoning.
2. RUSH to a health care facility!
3. DO NOT induce vomiting. Ipecac is not recommended for ingestion of sodium cyanide.
4. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
5. 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.
6. 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. (EPA, 1998)

Physical Properties

Chemical Formula:
  • CNNa
Flash Point: Not combustible (EPA, 1998)
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: Not flammable (USCG, 1999)
Melting Point: 1047°F (EPA, 1998)
Vapor Pressure: 1 mmHg at 1502.6°F (EPA, 1998)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.6 at 77°F (USCG, 1999) - Denser than water; will sink
Boiling Point: 2725°F at 760 mmHg (EPA, 1998)
Molecular Weight: 49.01 (EPA, 1998)
Water Solubility: greater than or equal to 100 mg/mL at 68°F (NTP, 1992)
Ionization Energy/Potential: data unavailable
IDLH: 25 mg CN/m3 (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Sodium cyanide (143-33-9)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 5 mg/m3 34 mg/m3 54 mg/m3
30 minutes 5 mg/m3 20 mg/m3 42 mg/m3
60 minutes 4 mg/m3 14 mg/m3 30 mg/m3
4 hours 2.6 mg/m3 7 mg/m3 17 mg/m3
8 hours 2 mg/m3 5 mg/m3 13 mg/m3
(NAC/NRC, 2023)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Sodium cyanide (143-33-9) 4 mg/m3 14 mg/m3 30 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
Cyanide Compounds N106 & 313
Sodium cyanide (Na(CN)) 143-33-9 100 pounds 10 pounds 10 pounds 313c P106

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Sodium cyanide 143-33-9 ACG APA sabotage/ contamination

(CISA, 2007)

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names