- Mercury(II) oxide
- Mercury monoxide
Red or orange-red odorless, dense crystalline powder or scales, yellow when finely powdered.
Similar to that of the red oxide, fungicide.
Registry Numbers and Inventories.
EC Index Number
very toxic, dangerous for the environment
R 26/27/28 33 50/53
S 13 28 45 60 61
Agricultural Chemical and Pesticide; Tumorigen; Reproductive Effector
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Decomposition point, °C
Vapor pressure, mmHg
701.968 (667.45 C)
0.6 (butyl acetate=1)
Solubility in water
Hazards and Protection.
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Wash thoroughly after handling. Wash hands before eating. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Minimize dust generation and accumulation. Wash clothing before reuse.
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Vacuum or sweep up material and place into a suitable disposal container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. If sweeping is necessary, use a dust suppressant agent. Avoid generating dusty conditions. Provide ventilation.
Stable at room temperature in closed containers under normal storage and handling conditions.
Chlorine, hydrazine hydrate, hydrogen peroxide, hypophosphorus acid, iodine + methyl and ethyl alcohol, magnesium, phospham, phosphorus, sodium + potassium, sulfur, reducing agents, easily oxidized materials, phosphinic acid.
Mercury/mercury oxides, oxygen.
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use water spray to keep fire-exposed containers cool. Containers may explode when heated. Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Extinguishing media: Do NOT get water inside containers. Do NOT use straight streams of water. For small fires, use dry chemical, carbon dioxide, or water spray. For large fires, use water spray, fog or regular foam. Cool containers with flooding quantities of water until well after fire is out.
Slight fire hazard, by chemical reactions; an oxidizer.
When heated to decomposition (932F) it decomposes into mercury and oxygen. Fumes from fire may contain poisonous mercury vapor; oxygen may increase intensity of fire. Explosion of mercuric oxide may occur with friction or application of heat. Avoid reducing agents. Avoid light; may decompose into mercury and oxygen.
Fire may produce irritating, corrosive and/or toxic gases.
NIOSH REL: C 0.1 mg/m3 [skin] OSHA PEL: C 0.1 mg/m3 10 mg/m3 (as Hg)
Overexposure may cause delayed kidney injury. Prolonged or repeated skin contact may cause dermatitis. Prolonged or repeated exposure can cause psychic abnormalities such as anxiety, depression and excitability. May cause adverse nervous system effects including muscle tremors and incoordination. May cause reproductive and fetal effects.
May be fatal if swallowed. May cause severe and permanent damage to the digestive tract. Causes gastrointestinal irritation with nausea, vomiting and diarrhea. May cause kidney damage. Inorganic mercury compounds may cause central and peripheral nervous system effects.
May cause respiratory tract irritation. May cause abdominal pain, nausea, vomiting, and inflammation of the gums and mouth. Acute exposure to high concentrations of mercury vapors may cause severe respiratory tract irritation. May cause liver damage.
May cause mild skin irritation. Harmful if absorbed through the skin.
May cause eye irritation. Contact may cause ulceration of the conjunctiva and cornea.
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid immediately. Induce vomiting by giving one teaspoon of Syrup of Ipecac.
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
Get medical aid immediately. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.
USCG CHRIS Code
2825 90 50