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Chemical Datasheet


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
  • 592-85-8
  • Poison
NFPA 704
data unavailable
NIOSH Pocket Guide International Chem Safety Card
Mercury compounds [except (organo) alkyls] (as Hg)external link none
General Description
An odorless white crystalline powder. Insoluble in water and denser than water. Hence sinks in water. Very toxic by inhalation and ingestion.


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
Air & Water Reactions
Insoluble in water.
Fire Hazard
Special Hazards of Combustion Products: When heated, decomposes into mercury, nitrogen, etc., at about 165°C.

Behavior in Fire: When heated, swells up to many times its original volume. (USCG, 1999)
Health Hazard
INHALATION: Acute poisoning symptoms are: Tightness in the chest, difficulty in breathing, coughing, and pain in the chest. EYES: Ulceration of conjunctiva and cornea. SKIN: Irritation, sensitization dermatitis. INGESTION: Necrosis, pain, vomiting, severe purging. Patient may die within a few hours from peripheral vascular collapse. (USCG, 1999)
Reactivity Profile
MERCURY THIOCYANATE decomposes into its elements at about 165°C. Burns readily in air to generate a coil of cohesive ash resembling a serpent (hence used in a firework: Pharaoh's serpents). Swells up to many times its original volume if heated (USCG, 1999). Soluble in dilute hydrochloric acid [Merck]. Incompatible with strong oxidizing agents.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

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 151 [Substances - Toxic (Non-combustible)]:

As an 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, in the downwind direction, as necessary, the isolation distance shown above.

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, 2016)
Excerpt from ERG Guide 151 [Substances - Toxic (Non-combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Water spray, fog or regular foam. Move containers from fire area if you can do it without risk. Dike fire-control water for later disposal; do not scatter the material. Use water spray or fog; do not use straight streams.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned hose holders 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 hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2016)
Non-Fire Response
Excerpt from ERG Guide 151 [Substances - Toxic (Non-combustible)]:

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, 2016)
Protective Clothing
Dust mask or self-contained breathing apparatus, when required; rubber gloves, safety or chemical goggles, disposable clothing, or rubber apron. (USCG, 1999)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Get medical attention.

INHALATION: Remove from exposure.

EYES: Flush with water.

SKIN: Wash thoroughly with water.

INGESTION: Give egg white, milk, or activated charcoal, then induce vomiting. Consult physician. (USCG, 1999)

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.
Chemical Formula:
  • C2N2S2.Hg
Flash Point: greater than 250 ° F (USCG, 1999)
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 Approximately (USCG, 1999)
Boiling Point: Decomposes about 329.0° F (USCG, 1999)
Molecular Weight: 316.79 (USCG, 1999)
Water Solubility: data unavailable
Ionization Potential: data unavailable
IDLH: 10 mg/m3 for Mercury compounds [except (organo) alkyls] (as Hg) (NIOSH, 2016)

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 thiocyanate; (Mercuric sulfocyanate) (592-85-8) 0.12 mg/m3 0.16 mg/m3 44 mg/m3
(DOE, 2016)

Regulatory Information

The Regulatory Information fields include information from the U.S. Environmental Protection Agency's Title III Consolidated List of Lists and the U.S. Department of Homeland Security's Chemical Facility Anti-Terrorism Standards (see more about these data sources).

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
CAA 112(r)
Mercuric thiocyanate 592-85-8 10 pounds 313c
Mercury Compounds N458 & 313

(EPA List of Lists, 2015)

DHS Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

Alternate Chemical Names

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