Radiation hazard assessment from NORM-added paint products in Malaysia

Abstract

Introduction: Across the globe, radioactive consumer products are widely marketed for daily use. Objectives: The present study investigated commercially available ion paint, and the evaluations were using gamma (γ)-ray spectroscopy and Geant4 Monte Carlo (GMC) simulations. Methods: An assessment of a radiological risk arising from using such products in the painting of living areas is conducted when Technologically Enhanced Naturally Occurring Radioactive Material (TENORM) was observed, with a daily inhalation exposure dose being of particular concern. Organ doses were simulated using adult mathematical Medical Internal Radiation Dose 5 (MIRD5)-type phantoms, incorporating dose conversion factors (DCFs). Results: Results showed that a product sample code of IP04 contained the highest activity, i.e., 4449 ± 530, 31888 ± 2175, and 2963 ± 405 Bq kg−1, for 238U, 232Th, and 40K, respectively. Contrarily, NP18 recorded the lowest, i.e., 16 ± 2 and 30 ± 5, Bq kg−1 of 238U and 232Th, respectively. The IP04 paint offered the most significant concentrations, with mean percentages of 0.026, 0.81, and 0.06 for 238U, 232Th, and 212Pb, respectively. Its use in a designated Room 1 had resulted in an annual effective dose of 1.53 mSv y−1, assuming an exposure for a period of 8 h day−1. Conclusion: In brief, using these ion paints could result in amounts that exceed the annual public dose limit of 1 mSv.