Back to top

• Consult safety resources available on the web:
  • Material Safety Data Sheet (MSDS) Sources
  • Laboratory Chemical Safety Summary: Osmium Tetroxide, "Prudent Practices in the Laboratory: Handling and Disposal of Chemicals" (1995)
• Know about these physical characteristics:
  • Osmium tetroxide is:
  • Noncombustible
  • Colorless to pale yellow-green when solid
  • Moderately soluble in water
  • A strong oxidizer
  • Osmium tetroxide will sublime (pass directly from solid to vapor and back to solid) readily at room temperature and significantly when refrigerated.
• Consider these hazards specific to osmium tetroxide:
  • Highly toxic (LD50 oral [rat] 14 mg/kg)
  • Ingesting very small amounts can cause death.
  • Severe irritant to the eyes and respiratory tract
  • Acute or chronic exposure can be severe with the following possible results:
  • Severe damage to the eyes, even blindness
  • Dermatitis
  • Inhalation can lead to lung or kidney damage
  • Chemical burns to the respiratory tract
• If possible, use a less dangerous product that can perform the same task.

  Back to top

• Inform employees about handling osmium tetroxide, its specific hazards, and health effects.
• Explain possible routes of exposure, as appropriate:
  • Skin absorption
  • Ingestion
  • Inhalation
• Provide personal protective equipment and engineering controls, and train employees in their proper use.
• Post emergency procedures in the lab and make sure everyone who works with osmium tetroxide is familiar with them.
• Consult the chemical safety officer, (858) 822-1579, on training procedures for any new or revised projects involving large quantities of osmium tetroxide.
• Keep training records on file, including:
  • Information covered
  • Date
  • Names
  • Employee signatures

  Back to top

• Keep a chemical spill kit easily accessible.
• Read How to Handle Chemical Spills in Laboratories.
• Print and keep the Material Safety Data Sheet for osmium tetroxide with your emergency supplies.
• Know the location of safety equipment, including eyewash, shower station, first aid kit, and Emergency Guide.
• Clean up only small quantities of osmium tetroxide, and only if you have been properly trained.
  • Note: Corn oil deactivates osmium tetroxide.
  • Use chemical absorbent pads for solutions, as described in the chemical spill kit instructions.
  • Cover solid osmium tetroxide spills with sand, sweep up, and place in a tightly sealed container.
• Dispose of all spill containment material as hazardous waste.

  Back to top

• Buy the least amount of osmium tetroxide the work requires. Do not buy in large quantities to save money.
• Label all containers with this information:
  • Name of the material
  • Concentration
  • Warnings
  • Date
  • Preparer's initials
• Label the work area with a sign saying "Osmium Tetroxide Use Area."
• Follow these storage guidelines:
  • Store in a tightly sealed container.
  • Place the container in a secondary container large enough to capture the entire contents should the primary container leak or rupture.
  • Store away from acids, bases, metals, strong reducing agents, and strong oxidizing agents.
  • Contact an EH&S Research Assistance Program specialist if you have questions about chemical and container compatibility.
  • Store separately from hydrochloric acid. Osmium tetroxide reacts with hydrocholoric acid to form chlorine gas.
  • Refrigerated osmium tetroxide: Put the osmium tetroxide in a glass-vacuum-type blood collection tube to prevent vapors from escaping into the refrigerator.

  Back to top

• Engineering controls: Work with osmium tetroxide in a chemical fume hood to reduce risk of inhalation. Never work with it on the open bench top.
• Wear this personal protective equipment (PPE):
  • Lab coat with sleeves fully extended to the wrists
  • Safety glasses or splash goggles
  • 2 layers of nitrile surgical gloves
  • Full-length pants
  • Closed-toe shoes
  Follow these PPE guidelines:
  • Always double-check your PPE before each use of osmium tetroxide.
  • Never re-use disposal gloves.
  • Leave all personal protective equipment in the lab when your work is complete.
• Restrict access to the work area.
• Keep container sizes and quantities in the work area as small as possible.
• Perform a dry run to work out any potential pitfalls.
• If you suspect equipment has been contaminated with osmium tetroxide, contact an EH&S Research Assistance Program specialist.

  Back to top

• Ingestion: Seek medical attention immediately.
• Skin exposure: Flush exposed skin with water for at least 15 minutes while removing any contaminated clothing.
• Eye exposure: Flush eyes with water for at least 15 minutes. Affected individuals may need help holding their eyes open under water.
• For all exposures:
  • Seek medical attention immediately at an emergency room.
  • Call UCSD Police at (858) 534-4357 (534-HELP) and request an ambulance if transportation is necessary.
  • Call the Poison Control System: (800) 222-1222, if additional information is needed.

  Back to top

• Read how to:
  • Store and dispose of hazardous and extremely hazardous chemical waste
  • Request a hazardous waste collection

  Back to top