Availability of Radioiodines in Fallout.
Final rept. 5 Oct 71-30 Jun 73,
GULF GENERAL ATOMIC CO SAN DIEGO CALIF
Pagination or Media Count:
A review of the behavior of radioiodine in fallout according to diffusion limited fission product absorption is presented. It suggests that radioiodines are highly fractionated. The isotopes I-131 through I-135 vary from calculated surface loadings of about 70 for I-131 to about 100 for I-135 for silicate fallout. Coral fallout is expected to have even higher fractions of surface loading. Experiments have been performed to evaluate the vaporization and liquid leaching of iodides from fission recoil loaded samples and vapor loaded substrate. Liquid leaching has been demonstrated as fast for surface oriented iodine. Vapor leaching has been demonstrated as being slow with the exception that exposure to direct environmental conditions greatly accelerates the iodine release. The major effect is thought to be due to sunlight. Ion microprobe studies to observe fission products in a high specific activity fallout were unsuccessful. The instrument did prove capable of some valuable microprobe type studies. Author