Chemical Datasheet

ARSENIC DISULFIDE

Chemical Identifiers

CAS Number	UN/NA Number	DOT Hazard Label	USCG CHRIS Code
1303-32-8 (replaced by 12044-79-0) 12044-79-0	1557	Poison	ARD
NIOSH Pocket Guide		International Chem Safety Card
Arsenic (inorganic compounds, as As)		none

NFPA 704

data unavailable

General Description

An odorless red-brown solid. Insoluble in water and denser than water. Hence sinks in water. Highly toxic by ingestion and inhalation.

Hazards

Reactivity Alerts

Strong Reducing Agent

Air & Water Reactions

Burns with a blue flame when heated in air [Mellor 9:270 1946-47]. Insoluble in water.

Fire Hazard

Special Hazards of Combustion Products: Poisonous fumes of the compound may be formed in fires. If ignited, will form sulfur dioxide gas.

Behavior in Fire: May ignite at very high temperatures (USCG, 1999)

Health Hazard

(Acute and sub-acute poisoning are not common.) Repeated inhalation causes irritation of nose, laryngitis, mild bronchitis. Ingestion causes weakness, loss of appetite, gastrointestinal disturbances, peripheral neuritis, occasional hepatitis. Contact with eyes causes irritation. Irritates skin, especially where moist; if not treated, may cause ulceration. (USCG, 1999)

Reactivity Profile

ARSENIC DISULFIDE reacts with oxidizing agents to generate heat and products that may be flammable, combustible, or otherwise reactive. These reactions may be violent. Soluble in acids and alkalis, but not soluble in water. Generates toxic gaseous hydrogen sulfide on contact with acids.

Belongs to the Following Reactive Group(s)

Sulfides, Inorganic

Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation

Excerpt from ERG Guide 152 [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 tank car or highway tank 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, 2024)

Firefighting

Fire Extinguishing Agents: Water (USCG, 1999)

Non-Fire Response

Excerpt from ERG Guide 152 [Substances - Toxic (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. 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, 2024)

Protective Clothing

Approved respirator; goggles; rubber gloves; clean protective clothing (USCG, 1999)

DuPont Tychem® Suit Fabrics

No information available.

First Aid

Consult physician after all overexposure to this compound.

INHALATION: move to fresh air.

INGESTION: induce vomiting by giving warm salt water; repeat until vomit is clear.

EYES: flush with water for at least 15 min.

SKIN: wash well with water. (USCG, 1999)

Physical Properties

Chemical Formula:

As2S2

Flash Point: data unavailable

Lower Explosive Limit (LEL): data unavailable

Upper Explosive Limit (UEL): data unavailable

Autoignition Temperature: data unavailable

Melting Point: 585°F (USCG, 1999)

Vapor Pressure: data unavailable

Vapor Density (Relative to Air): data unavailable

Specific Gravity: 3.5 at 68°F (USCG, 1999) - Denser than water; will sink

Boiling Point: 1049°F at 760 mmHg (USCG, 1999)

Molecular Weight: 214 (USCG, 1999)

Water Solubility: data unavailable

Ionization Energy/Potential: data unavailable

IDLH: 5 mg As/m3 ; A potential occupational carcinogen. (NIOSH, 2024)

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

No PAC information available.

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
Arsenic Compounds	N020			&	313
Arsenic disulfide	12044-79-0			1 pound	313c

313c indicates that although not listed by name and CAS number, this chemical is reportable under one or more of the EPCRA section 313 chemical categories.
& indicates that no RQ is assigned to this generic or broad class, although the class is a CERCLA hazardous substance. See 50 Federal Register 13456 (April 4, 1985).

(EPA List of Lists, 2024)

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

ARSENIC DISULFIDE
REALGAR
RED ARSENIC GLASS
RED ARSENIC SULFIDE
RED ORPIMENT
RUBY ARSENIC