LCSS: HYDROGEN PEROXIDE

HYDROGEN PEROXIDE
Substance	Hydrogen peroxide (Hydrogen dioxide) CAS 7722-84-1
Formula	HOOH
Physical Properties	Colorless liquid bp 150 °C, mp -0.4 °C Miscible in all proportions in water
Odor	Slightly pungent, irritating odor
Vapor Density	1.15 (air = 1.0)
Vapor Pressure	1 mm Hg at 15.3 °C 5 mm Hg at 30 °C
Flash Point	Noncombustible
Autoignition Temperature	None
Toxicity Data	LD₅₀ oral (rat) 75 mg/kg (70%) LD₅₀ skin (rabbit) 700 mg/kg (90%) LD₅₀ skin (rabbit) 9200 mg/kg (70%) LC₅₀ inhal (rat) >2000 ppm (90%) PEL (OSHA) 1 ppm (1.4 mg/m³) (90%) TLV-TWA (ACGIH) 1 ppm (1.4 mg/m³) (90%)
Major Hazards	Contact with certain metals and organic compounds can lead to fires and explosions; concentrated solutions can cause severe irritation or burns of the skin, eyes, and mucous membranes.
Toxicity	Contact with aqueous concentrations of less than 50% cause skin irritation, but more concentrated solutions of H₂ O₂ are corrosive to the skin. At greater than 10% concentration, hydrogen peroxide is corrosive to the eyes and can cause severe irreversible damage and possibly blindness. Hydrogen peroxide is moderately toxic by ingestion and slightly toxic by inhalation. This substance is not considered to have adequate warning properties. Hydrogen peroxide has not been found to be carcinogenic in humans. Repeated inhalation exposures produced nasal discharge, bleached hair, and respiratory tract congestion, with some deaths occurring in rats and mice exposed to concentrations greater than 67 ppm.
Flammability and Explosibility	Hydrogen peroxide is not flammable, but concentrated solutions may undergo violent decomposition in the presence of trace impurities or upon heating.
Reactivity and Incompatibility	Contact with many organic compounds can lead to immediate fires or violent explosions (consult Bretherick for references and examples). Hydrogen peroxide reacts with certain organic functional groups (ethers, acetals, etc.) to form peroxides, which may explode upon concentration. Reaction with acetone generates explosive cyclic dimeric and trimeric peroxides. Explosions may also occur on exposure of hydrogen peroxide to metals such as sodium, potassium, magnesium, copper, iron, and nickel.
Storage and Handling	Hydrogen peroxide should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the procedures for work with reactive and explosive substances (Chapter 5.G). Use extreme care when carrying out reactions with hydrogen peroxide because of the fire and explosion potential (immediate or delayed). The use of safety shields is advisable, and is essential for experiments involving concentrated (>50%) solutions of hydrogen peroxide. Sealed containers of hydrogen peroxide can build up dangerous pressures of oxygen, owing to slow decomposition.
Accidents	In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If hydrogen peroxide is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once. In the event of a spill, remove all ignition sources, soak up the hydrogen peroxide with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal	Excess hydrogen peroxide and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines.
The information in this LCSS has been compiled by a committee of the National Research Council from literature sources and Material Safety Data Sheets and is believed to be accurate as of July 1994. This summary is intended for use by trained laboratory personnel in conjunction with the NRC report Prudent Practices in the Laboratory: Handling and Disposal of Chemicals. This LCSS presents a concise summary of safety information that should be adequate for most laboratory uses of the title substance, but in some cases it may be advisable to consult more comprehensive references. This information should not be used as a guide to the nonlaboratory use of this chemical. Copyright 1995 National Academy of Sciences. All rights reserved.