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Chemical Datasheet

POTASSIUM SILVER CYANIDE

6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 506-61-6
  • 1588
  • Poison
none
NIOSH Pocket Guide International Chem Safety Card
Silver (metal dust and soluble compounds, as Ag) none
NFPA 704
data unavailable
General Description
White crystals. Poisonous. Used in silver plating, as a bactericide and in the manufacture of antiseptics. Not registered as a pesticide in the U.S. (EPA, 1998)

Hazards

Reactivity Alerts
none
Air & Water Reactions
Water soluble [Merck].
Fire Hazard
When heated to decomposition, potassium silver cyanide emits very toxic fumes of cyanide and nitrogen oxides. Avoid light. (EPA, 1998)
Health Hazard
The primary health hazard is as a cyanide. (Non-specific -- Cyanide, Inorganic, n.o.s.). It is poisonous and may be fatal if inhaled, swallowed or absorbed through the skin. Fire may produce irritating or poisonous gases. (EPA, 1998)
Reactivity Profile
POTASSIUM SILVER CYANIDE is light sensitive. Acids precipitate silver cyanide from its aqueous solution. Fusion with metal chlorates, perchlorates, nitrates or nitrites can cause violent explosions [Bretherick 1979 p. 101].
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: 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
(Non-Specific -- Cyanide, Inorganic, n.o.s.) 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. Fight fire from maximum distance. Dike fire control water for later disposal. Do not scatter the material.

(Non-Specific -- Cyanide, Inorganic, n.o.s.) Use dry chemical, carbon dioxide, water spray, or foam for small fire, and water spray, fog, or foam for large fires. Move containers of this material away from fire area if this can be done without risk. (EPA, 1998)
Non-Fire Response
Avoid inhalation or skin contact. (Non-Specific -- Cyanide, Inorganic, n.o.s.) Do not touch spilled materials; 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)
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: Effects, including skin reactions, may be delayed. Caution is advised. Vital signs should be monitored closely. Heart palpitation may begin within minutes after exposure.

Note: Potassium silver cyanide is very readily absorbed through the skin.

Signs and Symptoms of Potassium silver cyanide Exposure: Signs and symptoms of acute exposure to potassium silver cyanide may include hypertension (high blood pressure) and tachycardia (rapid heart rate), followed by hypotension (low blood pressure) and bradycardia (slow heart rate). Cherry-red mucous membranes and blood, cardiac arrhythmias, and other cardiac abnormalities are common. Cyanosis (blue tint to the skin and mucous membranes) is not a consistent finding. Tachypnea (rapid respiratory rate) may be followed by respiratory depression. Lung hemorrhage and pulmonary edema may also occur. Headache, vertigo (dizziness), agitation, and giddiness may be followed by combative behavior, convulsions, paralysis, protruding eyeballs, dilated and unreactive pupils, and coma. Potassium silver cyanide is irritating to the skin and mucous membranes. Lacrimation (tearing) and a burning sensation of the mouth and throat are common. Excessive salivation, nausea, and vomiting may also occur.

Emergency Life-Support Procedures: Acute exposure to potassium silver cyanide 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 potassium silver 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 potassium silver 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 potassium silver 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 potassium silver cyanide-contaminated persons or their gastric contents may result in self-poisoning.
3. Rush to a health care facility.
4. Remove and isolate 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 thoroughly with 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 potassium silver cyanide-contaminated persons or their gastric contents may result in self-poisoning.
2. Rush to a health care facility.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. DO NOT induce vomiting or attempt to neutralize!
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. 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. (EPA, 1998)

Physical Properties

Chemical Formula:
  • KAg(CN)2
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: 2.36 at 77°F (EPA, 1998) - Denser than water; will sink
Boiling Point: data unavailable
Molecular Weight: 199.01 (EPA, 1998)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: 10 mg Ag/m3 (NIOSH, 2023)

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
Potassium silver cyanide (506-61-6) 2.9 mg/m3 32 mg/m3 190 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
Potassium silver cyanide 506-61-6 500 pounds 1 pound 1 pound 313c P099
Silver Compounds N740 & 313

(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