PLA-Based Simulator for Dosimetry Assessment of Healthcare Waste

Healthcare waste (HCW) requires efficient treatment prior to final disposal to prevent the spread of pathogens and environmental contamination. Ionizing irradiation has emerged as a promising alternative to incineration; however, accurate absorbed-dose determination depends on knowledge of the material’s radiological properties. This work aims to develop a physical simulator for HCW to support dosimetric evaluation of irradiated waste, including experimental and computational validation. Data from the National Institute of Standards and Technology (NIST), along with the XCOM and ESTAR programs, were used to obtain mass energy-absorption coefficients for photons and mass stopping power for electrons in the energy range of 0.1 to 20 MeV. Two approaches were considered: a full compositional model representative of typical HCW, and a simplified model based on Polylactic Acid (PLA), containing only C, O, and H, assuming that PLA adequately reproduces the predominant elemental fraction of the waste. Dosimetric validation was performed by comparing mass attenuation coefficients (μ) and stopping power (S) between HCW and PLA. Computational simulations using PHITS evaluated the spatial dose distribution from photons and electrons. A physical simulator was subsequently manufactured by 3D printing in PLA, with a density of 0.15 g/cm³ and internal hexagonal geometry to reflect realistic waste packing characteristics. Comparisons of attenuation and stopping power coefficients showed minimal differences between HCW and PLA, demonstrating radiological equivalence. Simulations and analyses confirmed that the simulator effectively reproduces the spatial dose distribution, with good homogeneity and fidelity to real behavior. The use of PLA proved to be a practical, economical, and technically consistent solution for constructing simulators aimed at improving dosimetric processes in ionizing radiation treatment of healthcare waste, while also enabling reproducible studies with strong potential for practical application.