³²₁₆S + ¹₀n → ³²₁₅P + ¹₁p
or, in still more abbreviated form, ³²Sn,p³²P. Phosphorus-32 atoms do not emit gamma rays upon disintegration and so are not detected in standard whole body counters. Attempts are being made, however, to adapt some whole body counters to pick up the secondary radiations, called bremsstrahlung, that occur when the high-energy beta particles that are emitted by phosphorus-32 collide with other atoms.
Figure 14 Whole body counter record of evidence that a cyclotron worker has picked up higher-than-average quantities of radioactive zinc-65. Note how the graph shows peaks at specific energy levels identifying the radionuclides.
Figure 15 Graphic evidence that a radioactive gas accidentally inhaled by a worker at an experimental reactor contained 3 radioactive isotopes of iodine.
Figure 16 The number of 1.38-Mev gamma rays emitted by sodium-24 in the body of a reactor accident victim indicates he received about 900 rads of neutron irradiation.
Figures [14] through [16] illustrate the kind of data that whole body counters provide to help physicians care for people involved in accidents.
Similarly, neutron bombardment of natural sodium (²³Na) atoms in the body produces sodium-24. This reaction is written: ²³Na(n, gamma ray)²⁴Na. The 1.38-Mev gamma rays emitted by sodium-24 are detected effectively by whole body counters. Since a given neutron dose converts a known proportion of ²³Na atoms to ²⁴Na, it is possible to determine how much neutron exposure a worker has received by obtaining his body count of radioactive sodium.