HP-27: P-32 Handling and Other Information

Phosphorus-32 is a commonly used radionuclide with a half-life of 14.3 days, emitting beta particles with a maximum energy of 1.71MeV. The beta particles travel a maximum of 20 feet in air.

• Surface radiation exposure to the skin of the hands
• A drop of contamination containing 1 microcurie of P-32 on 1 cm² area of the skin produces an exposure of 2,000 mrem/hour
• Radiation exposure in air over an open vial
• The dose rate at the opening of a vial containing 1 mCi of P-32 can be as high as 26000 mrem/hour

Plexiglass (lucite) is the best shield for beta particles from P-32. When more than 1 mCi of P-32 is handled, a sufficient number of x-rays (bremmstrahlung) may be formed to require lead foil to be added to the exterior of the shield. The beta particles travel a maximum of 3.1 mm in glass, 6.7 mm in lucite, and 8 mm in tissue.

A tiny drop of contamination of P-32 can be easily detected with a Geiger Counter.

The following equipment and supplies must be available:

• A Geiger Counter sensitive to beta particles
• A plexiglass benchtop shield.
• Disposable latex or plastic gloves.
• Film badge and ring badge.
• Full-length lab coat.
• Plexiglass containers for radioactive waste.
• Pipettes dedicated to the use of P-32.
• Plastic safety glasses.
• Commercial decontaminate

If the following safety rules are followed, personnel radiation exposure will be as low as reasonably achievable.

• Designate a specific area of the lab for P-32 handling
  • Place the plexiglass shield near a wall (not toward another work area on the other side of the bench) away from the main flow of traffic in the lab
• All persons in the laboratory must wear a whole body film badge when in the lab, even those who are not handling P-32
• All persons handling P-32 must wear a ring badge on the hand which is most frequently used to handle vials, samples, pipettes, etc. containing P-32
• Full-length lab coats must be worn by all persons who handle P-32
• Protect the skin of your hands from becoming contaminated by wearing two pairs of disposable gloves
• A Geiger counter must be in operation during the experiment, and preferably at all other times
  • To avoid contaminating the detector, place a thin sheet of plastic (i.e., Saran Wrap) around the detector
• Place all vials and test tubes containing P-32 behind a plexiglass shield
  • Check the radiation level in front of the shield to determine if Lead foil should be added to block out the x-rays (called bremstrahlung) formed by the beta particles interacting with the plexiglass
• Do not work directly over an open container of P-32
• Never pipette 32P by mouth
• Only use pipettes which have been dedicated to your specific use of P-32
  • Pipettes will easily become contaminated and therefore, should not be shared with others
• Use the Geiger Counter to check your gloves frequently for contamination
  • If contamination is found, immediately dispose of the gloves in the radioactive waste container

For example, if your vial contained 250 uCi of P-32 on 07 Aug 98, the amount of activity remaining on 19 Aug 98 (12 elapsed days) would be:

Activity x Decay Factor = 250 uCi x 0.559 = 139.75 uCi