Phosphorus-32 is a commonly used radionuclide with a half-life
of 14.3 days, emitting beta particles with a maximum energy of 1.71
MeV (Million Electron Volts).
The major concerns with using P-32 are:
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 millirems / hour.
Radiation exposure in air over an open vial: The dose rate at the
opening of a vial containing 1 millicurie of P-32 can be as high as
26,000 millirems per hour.
Working with P-32 orthophosphate in high concentrations: Using
thophosphate poses significant problems because of the large
activity and high concentrations (i.e., 5 millicuries in 10 lambda
!). If you can avoid using them, please do so.
Using lower concentrations of P-32 in any form is very
desirable. Most companies will provide lower concentrations if
requested. The cost of using pre-labelled materials or lower
concentrations is higher but the return in safety more than offsets
the additional cost.
The following equipment and supplies must be available:
- A Geiger Counter sensitive to beta particles calibrated by
EH&S and a liquid scintillation counter.
- We recommend the Ludlum Model 3-98 or an equivalent. This
device will allow the detection not only of P-32's beta particles
but also the secondary x-rays.
- 3/8" or 1/2" Plexiglas benchtop shield. These are available
from many lab equipment vendors. The Health Science Fabrication
Department in Farber Hall (829-2477) on the South Campus can also
custom make one for you. If you are going to handle more than 1
millicurie, we recommend the 1/2" thickness.
- Disposable latex or plastic gloves.
- Film badge and ring badge.
- Full-length lab coat.
- EH&S approved waste containers (P-32 Decay Storage box for
dry waste; P-32 Decay Sorage Organic Liquid container for
scintillation waste; Aqueous Liquid container for water based
- Plexiglass shields for radioactive waste containers. These are
available from many lab equipment vendors such as VWR, Fisher, etc.
but also may be customed made at the Health Science Fabrication
- Pipettes dedicated to the use of P-32.
- Plastic safety glasses.
- Commercial decontaminate, i.e. DuPont's "Count Off".
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 Plexiglas 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 should 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
- 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.
- Place all vials and test tubes containing P-32 behind a 3/8" or
1/2" thick 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
- Do not work directly over an open container of P-32.
- Never pipette P-32 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
- If contamination is found, immediately dispose of the gloves in
the P-32 Decay Storage radioactive waste container
After handling P-32:
- Use the Geiger Counter to check your hands, shoes, clothing,
work bench, floor, centrifuges, and water baths for
- If any contamination is found on your shoes and/or clothing,
contact the EH&S.
- If any contamination is found on your hands, wash thoroughly
with soap and water. This will usually be sufficient to remove the
surface contamination. If it does not, contact EH&S for
- If any contamination is found on the work bench, floor, or lab
equipment, use a commercial radiation contamination remover (i.e.
Count Off) with paper towels to clean up the equipment. Place the
towels in the P-32 Decay Storage radioactive waste box.
- If contamination cannot be removed, place a "radiation" label
on the equipment indicating that it is P-32, maximum cpm found, and
the date you measured the level. Contact EH&S.
- If contamination cannot be removed from the floor, contact the
Radiation Safety to obtain shielding materials.
- Inform your fellow lab workers if any unremovable contamination
- Check the normal trash container to make sure no radioactive
waste has been accidentally placed there.
- Store the waste temporarily in plexiglass containers or other
containers which are sufficient to absorb P-32's beta
- Call EH&S if you have any questions about where to
- Wash your hands thoroughly after using P-32.
- Do not let the waste pile up. EH&S picks up waste on a
weekly basis. Call 829-3281 for waste pick up and delivery.