Management of Iodine at Nuclear Reactors

Of the several radioisotopes of iodine created in nuclear reactors only two, and are present in sufficient quantities in gaseous effluents to warrant installation of effluent control systems. 

Levels of in environmental samples have been determined by a number of investigators (Studier et al., 1962 Edwards and Rey, 1969 Keisch et al., 1963, 1964, 1965 Cochran et al., 1970 Matuszek et al., 1974 Markham, 1974 Magno et al., 1972 Boulos et al., 1973 Kelleher and Michael, 1973 Brauer, 1974 Brauer et al., 1974b Brauer and Ballou, 1975). The high analytic sensitivity for by activation analysis permits measurements at concentrations much below those required for radiation protection. 

Field concentration methods can be used to increase the quantity of in certain materials that are collected. Thus, particle filters and activated charcoal filters have been used to collect atmospheric iodine (Brauer et al., 1974a). Ion-exchange methods, usually using anion exchange resins, have been used to sample water-borne iodine and ionic iodine in milk (Daly et al., 1974 Brauer and Rieck, 1973 Brauer et al., 1974b Keisch et al., 1965). Natural iodine collectors, such as thyroid tissue and seaweed, have been used for collection of environmental I samples (Brauer et al., 1974b Keisch et al., 1964 NSEC, 1963 Boulos et al., 1973 Kelleher and Michael, 1973 Smith, 1977 Oliver et al., 1982 Schuttelkopf and Pimpl, 1982). 

The content of in environmental materials has been determined in both fresh and dry samples. Drying methods utilized include air drying, low-temperature oven drying, and freeze drying. 

Analysis of in environmental samples generally requires separation of the iodine from the materials of concern. The need for separation results from the low specific activity of its low-energy emissions, and its low environmental levels. Separation of iodine from environmental samples has been accomplished by both chemistry and combustion methods (Studier et al., 1962 Keisch et al., 1965 Magno et al., 1972 Boulos et al., 1973 Gabay et al., 1974 McFarland et al., 1974 Brauer and Tenny, 1975). 

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