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Chemical Datasheet

MERCURIC CYANIDE

6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 592-04-1
  • 1636
  • Poison
  • MCN
NIOSH Pocket Guide International Chem Safety Card
Mercury compounds [except (organo) alkyls] (as Hg) none
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
Odorless tetragonal crystals or white powder. Toxic by inhalation (dust, and the hydrogen cyanide from decomposition) and by ingestion. Toxic oxides of nitrogen are produced in fires.

Hazards

Reactivity Alerts
none
Air & Water Reactions
Soluble in water. Gradually decomposed by water to give off hydrogen cyanide, a flammable poison gas.
Fire Hazard
Special Hazards of Combustion Products: Fumes from fire may contain toxic mercury and hydrogen cyanide. (USCG, 1999)
Health Hazard
Symptoms of both cyanide and mercury intoxication can occur. Acute poisoning has resulted from inhaling dust concentrations of 1.2-8.5 mg/m 3 of air; symptoms include tightness and pain in chest, coughing, and difficul ty in breathing; cyanide poisoning can cause anxiety, confusion, dizziness, and shortness of breath, with possible unconsciousness, convulsions, and paralysis; breath may smell like bitter almonds. Ingestion causes necrosis, pain, vomiting, an d severe purging, plus the above symptoms. Contact with eyes causes ulceration of conjunctiva and cornea. Contact with skin causes irritation and possible dermatitis; systemic poisoning can occur by absorption through skin. (USCG, 1999)
Reactivity Profile
MERCURIC CYANIDE is rapidly decomposed by acids to give off hydrogen cyanide, a flammable poison gas. Decomposed in the light. May tend to explosive instability. Capable of violent reaction with oxidizing agents. Fusion with metal chlorates, perchlorates, nitrates or nitrites can cause a violent explosion [Bretherick 1979. p. 101].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-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 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

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. (ERG, 2020)
Non-Fire Response
Excerpt from 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-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. 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
Dust mask; goggles or face shield; rubber gloves (USCG, 1999)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Act quickly; call physician.

INHALATION: if victim has stopped breathing, start artificial respiration immediately; using amyl nitrite pearls, administer amyl nitrite by inhalation for 15-30 seconds of every minute while sodium nitrite solution is being prepared; discontinue amyl nitrite and immediately inject intravenously 10 ml of a 3% solution of sodium nitrite (nonsterile if necessary) over a period of 2-4 min.; without removing needle, infuse intravenously 50 ml of a 25% aqueous solution of sodium thiosulfate; injection should take about 10 min. (concentrations of 5-50% may be used, but keep total dose approx. 12 gm). Oxygen therapy may be helpful in combination with the above.

INGESTION: alimentary absorption is very rapid; action during first 10-15 min. determines prognosis. Give egg whites, milk, or activated charcoal and induce vomiting; treat for cyanide poisoning as above.

EYES or SKIN: wash with water for 15 min. (USCG, 1999)

Physical Properties

Chemical Formula:
  • Hg(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: 4 at 68°F (USCG, 1999) - Denser than water; will sink
Boiling Point: data unavailable
Molecular Weight: 252.63 (USCG, 1999)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: 10 mg Hg/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
Mercuric cyanide (592-04-1) 0.094 mg/m3 0.13 mg/m3 35 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
Mercuric cyanide 592-04-1 1 pound 313c
Mercury Compounds N458 & 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