I-123 is produced from Xe-123 in cyclotron (see Eq. (8.28)). Its half-life is 13 h, and it disintegrates with electron capture and gamma radiation. Because of its short half-life, the I-125 isotope is used in nuclear medicine for examinations of pregnant women and children.

I-125 is applied as irradiation source in X-ray fluorescence studies. Its half-life is 60 days, and it disintegrates with electron capture and gamma radiation. For more information, see Section 8.7.1.3.

I-131 is formed by the irradiation of tellurium and by beta decay of the product: 130Te(n, Y)131Te!131I. The half-life of 131I is 8 days, and it has в_ and gamma radiation. During the production of Mo-99 from the spent fuel elements of nuclear reactors, I-131 is separated by acidic treatment, that is, I-131 is a by-product of Mo-99 production. I-131 obtained in this way has a higher specific activity than I-131 produced by irradiation of tellurium. I-131 has important medical applica­tions. For more information, see Section 8.7.1.3.

8.6.17 Xenon Isotopes

Similar to Kr isotopes, xenon isotopes are fission products and emitted into the air from nuclear reactors and reprocessing plants.