- Styrene monomer
Colorless to light yellow liquid with a sweet, almost floral odor at low concentrations, sharp, penetrating, odor at high concentrations.
Manufacture of plastics, synthetic rubber, insulator.
Registry Numbers and Inventories.
EC Index Number
Flammable; Harmful; Irritant
R 10 20 36/38
Tumorigen; Mutagen; Reproductive Effector; Human Data; Primary Irritant
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
5 (23 C)
Vapor density (air=1)
0.59% at 20 C
Odor Threshold Odor threshold 0.047 ppm
0.906 g/cm3 (20 C)
Solubility in water
0.751 cp (20 C)
32.14 g/s2 at 19 C
1.5463 (20 C)
2.46 (20 C)
Partition coefficient, pKow
Heat of fusion
Heat of vaporization
Heat of combustion
Hazards and Protection.
Keep away from sources of ignition. Store in a cool place in the original container and protect from sunlight. Refrigerator/flammables.
B2 D2A D2B F
Wash thoroughly after handling. Use only in a well ventilated area. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Take precautionary measures against static discharges. Wash clothing before reuse. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
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 protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.
A half-face organic vapor respirator may be worn for up to ten times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. A full-face piece organic vapor respirator may be worn up to 50 times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. For emergencies or instances where the exposure levels are not known, use a full-face piece positive-pressure, air-supplied respirator.
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation.
Stable under normal temperatures and pressures.
Vapor is explosive when exposed to heat or flame; reacts with oxygen above 40C (104F) to form a heat-sensitive explosive peroxide. On exposure to light and air, styrene slowly undergoes polymerization and oxidation with formation of peroxides. Violent polymerization may be initiated by alkali metal-graphite composites, butyllithium, dibenzoyl peroxide, azoisobutyronitrile or di-tert-butyl peroxide. Styrene reacts violently with chlorosulfonic acid, oleum, sulfuric acid, chlorine + iron(II)chloride and can react vigorously with oxidizing materials. Dissolves rubber. Corrosive to copper and copper alloys. Incompatible with peroxides, aluminum chloride, strong acids, metallic salts, halogens, polymerization catalysts and accelerators.
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.
Upper exp. limit, %
Lower exp. limit, %
Wear full protective clothing and NIOSH-approved self-contained breathing apparatus with full facepiece operated in the pressure demand or other positive pressure mode. Extinguishing media: Water spray, dry chemical, alcohol foam, or carbon dioxide. Material floats on water and may travel back to an ignition source and spread fire. Water spray may be used to keep fire exposed containers cool. Do not allow water runoff to enter sewers or waterways.
Flammable liquid and vapor.
Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back. At elevated temperatures such as in fire conditions, polymerization may take place which may lead to container explosion.
Toxic gases and vapors (such as carbon monoxide) may be released in a fire involving styrene. Styrene fumes are very acrid.
OSHA PEL: TWA 100 ppm C 200 ppm 600 ppm (5-minute maximum peak in any 3 hours) NIOSH REL: TWA 50 ppm (215 mg/m3) ST 100 ppm (425 mg/m3) NIOSH IDLH: 700 ppm
Repeated exposure may cause nausea, vomiting, appetite loss, a sensation of drunkenness, general weakness, and functional disorders of the nervous system and liver. May cause dermatitis. Women may experience ovulation and menstrual disorders. May cause mutagenic and teratogenic effects.
May cause irritation to the gastrointestinal tract. Symptoms may include nausea, vomiting and diarrhea. May cause central nervous system depression. Symptoms may include lethargy, drowsiness, staggering and sleepiness. May cause possible convulsions and risk of pulmonary edema.
Causes irritation to the respiratory tract. Symptoms may include coughing, shortness of breath. A central nervous system depressant. Higher exposures can cause a build-up of fluid in the lungs (pulmonary edema), a medical emergency.
Causes irritation to skin. Symptoms include redness, itching, and pain. May produce blisters. May be absorbed through the skin.
May cause irritation, redness, pain, and corneal damage.
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists. Wash clothing before reuse.
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.