This contribution describes the effect of absorbing materials on the functionalization and the concentration of radicals of poly(tetrafluoroethylene) (PTFE) during the -irradiation compared to the results without absorbing materials. Different absorbing calcium-based materials were used to study their efficiency to avoid the release of fluorinated gases that occur within the irradiation procedure in the environment. It was found, that the type of the absorbing material had a significant effect on the formation and concentration of functional groups (carbonyl fluoride, carboxylic acid) and persistent radicals within the radiation-treated PTFE samples. In addition, by means of wide angle X-ray scattering (WAXS) the quantitative determination of fluorine (F-) concentration after irradiation in the absorbing materials could be followed. It may be used for scientific investigations of radiation induced PTFE chain scission mechanisms as well as for the monitoring of industrial -irradiation processes. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1787-1793, 2013