Background and Overview of Hazards

Uranium and thorium are naturally occurring radioactive materials with very long half-lives (4.5 billion years for U-238 and 14 billion years for Th-232). Both decay by alpha emission releasing a He2+ nucleus. Alpha radiation has a short range in air of a few centimeters and is blocked by a sheet of paper. Consequently, handling uranium and thorium does not pose an external radiation hazard. However, alpha radiation is extremely hazardous when taken into the body. In addition, the radioactive substance may pose chemical hazards such as high toxicity, chronic health effects, or chemical reactivity. Always consult the Safety Data Sheet for the specific chemical in use.

Good chemical hygiene practices, and contamination control is key to safe handling and preventing adverse effects for all materials.


Campus is required to track radioactive materials. For this reason, purchase orders for radioactive materials are routed to the Division of Research Safety for review. Exemptions are small amounts contained in articles or dilute solutions such as standards or uranyl staining solutions (e.g., uranyl acetate or formate). A radiation permit is usually not required to purchase small quantities from commercial vendors. All materials will be shipped to the Environmental Health and Safety Building and delivered to the lab on the same day. 


It is recommended to explore safer alternatives when radioactivity is not a desired property. Alternatives exist to uranyl solutions frequently used for microscopy staining. Those are free of radioactive isotopes and do not require DRS review. Examples are UranyLess and UA-Zero.  

Safe Handling

  • To prevent contamination of work areas, work on bench top paper when handling dispersible materials and solutions.
  • Wear a lab coat, gloves, and safety glasses.
  • Weigh dry powders in a chemical fume hood. If the balance is not located inside the hood, use the following procedure:
    1. Tare the container with lid.
    2. Add the chemical inside the fume hood.
    3. Close the container.
    4. Weigh the container.
    5. Add the solvent inside the hood.
  • Remove bench top paper when done. Next, clean the work area by wiping with soap and water.
  • Remove gloves immediately after handling the compounds and wash hands with soap and water.


DRS tracks the amounts on campus through purchasing and disposal. To maintain an accurate inventory, please be able to provide the approximate amount in your wastes. 

Waste Disposal

Always keep radioactive waste separate from non-radioactive wastes as much as possible. Collect all radioactive waste and items contaminated with radioactive isotopes in an appropriate container and mark with the radiation symbol (for example, utilize RAD tape). List the isotope and any other hazardous chemicals present. Submit to DRS for disposal:

  • Dry debris (bench top paper, gloves, pipette and pipette tips) can be collected in a bag. Yellow bags displaying the radiation symbol are commercially available. Submit under UI# 7 “Dry Radioactive Debris Waste Long-lived.”
  • Sharps (microscopy slides, glass Pasteur pipettes, syringes and needles) must be collected in a sharps disposal container. Sharps containers used primarily for microscopy slides are limited to two gallons to keep the weight manageable. Submit under UI# 3 “Sharps Disposal container with Radioactive Materials.”
  • Solutions should be collected in a closable waste container such as a Nalgene bottle or an empty and cleaned chemical bottle. Avoid mixing radioisotopes with hazardous chemicals (including ethanol, methanol, etc.) whenever possible, as this dual hazard waste incurs high disposal costs. Submit all radioactive liquid waste under the chemical name and check the radioactive material box.

Enter the isotope and isotope amount in the description. Estimates are acceptable and include activity, in µCi, or mass, in mg, that is contained in the contaminated waste. Provide your permit number if applicable.

More information on radioactive waste disposal can be found here.

Emergency Procedures

Skin Contact

Remove contaminated clothing and rinse off affected skin immediately with soap and copious amounts of water for at least 15 minutes. 

Eye Contact

Use the eye wash to rinse the eye thoroughly for at least 15 min, occasionally lifting upper and lower eyelids and rolling the eyeballs around.


Move into fresh air immediately. 

    Last Updated: 9/27/2023