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We have examined a dosimetry characteristic of carbonate hydroxyapatite (CO3HAp), which is a dental bone graft material. The purpose of this work is to investigate the reproducibility and stability of radiation-induced radicals on CO3HAp samples and assess the feasibility of using these materials as dosemeters. CO3HAp samples were exposed to gamma rays with dose range from 10 to 10 000 Gy. The electron spin resonance (ESR) spectra for irradiated samples were measured. Variation of peak-to-peak amplitude of the ESR signal intensity as a function of absorbed dose for CO3HAp was compared with that for alanine dosemeters, suggesting that the CO3HAp sample has a good linear dose response in the range from 10 to 10 000 Gy as well as does the alanine dosemeters., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Irradiation of ground beef and beef liver inoculated with Escherichia coli O157 466 and DT66 and Salmonella Enteritidis 3313 were performed with gamma rays from cobalt-60 at refrigerated and frozen temperatures under air- and vacuum-packaged conditions. Results showed that D 10 values for all pathogens in frozen beef liver were higher than those in frozen ground beef samples, with significant differences observed between the D 10 values of E. coli O157 466 and S. Enteritidis 3313 under air-packaged conditions, as well as in E. coli O157 DT66 and S. Enteritidis 3313 under vacuum-packaged conditions. To verify effective bacterial inactivation under high bacterial-contamination levels (10 5 -10 7  CFU/g), survival/death interfaces of E. coli O157 DT66 and S. Enteritidis 3313 inoculated in beef liver under vacuum-packaged and frozen conditions were constructed, with results suggesting that doses from 5.3 kGy to 5.5 kGy and 8.2 kGy-8.5 kGy would be sufficient to kill 10 5  CFU/g of E. coli O157 and S. Enteritidis 3313, respectively, at a 95%-99% predicted confidence interval. These results suggested that food matrixes containing high amounts of antioxidants (such as beef liver) and treated under frozen and vacuum-packaged conditions require additional consideration and evaluation for applications of irradiation treatment., (Copyright © 2018. Published by Elsevier Ltd.)