scholarly journals The Enhanced Naturally Occurring Radioactivity of Negative Ion Clothing and Attendant Risk

2021 ◽  
Vol 11 (12) ◽  
pp. 5412
Author(s):  
Halmat Jalal Hassan ◽  
Suhairul Hashim ◽  
Noor Zati Hani Abu Hanifah ◽  
Muhammad Fahmi Rizal Abdul Hadi ◽  
Mohamad Syazwan Mohd Sanusi ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Gamma Ray ◽  
Annual Effective Dose ◽  
Radioactive Material ◽  
Negative Ion ◽  
Dose Limit ◽  
Radiological Risk ◽  
Organ Doses ◽  
Naturally Occurring ◽  
Naturally Occurring Radioactive Material

The study investigates commercially available negative ion clothing, and evaluations are made using gamma-ray spectroscopy and Geant4 Monte Carlo simulations. Observed to contain naturally occurring radioactive material (NORM), evaluations are made of the radiological risk arising from the use of these as items of everyday wear, undergarments in particular. Organ doses from these were simulated using the MIRD5 mathematical female phantom, with the incorporation of dose conversion factors (DCFs). At 175 ± 26, 1732 ± 247, and 207 ± 38 Bq, for 238U, 232Th, and 40K respectively, item code S05 was found to possess the greatest activity, while item code S07 was shown to have the least activity, at 2 ± 0.5 and 15 ± 2 Bq, and again for 238U and 232Th, respectively. Sample code S11 recorded least activity, at 29 ± 5 Bq, for 40K. Among the clothing items, sample item code S05 offered the greatest concentrations of Th, U and Zr, with percentage means of 1.23 ± 0.1, 0.045 ± 0.001, and 1.29 ± 0.1, respectively, giving rise to an annual effective dose of 1.57 mSv/y assuming a nominal wearing period of 24 h per day. Accordingly, the annual public dose limit of 1 mSv can be exceeded by their use.

scholarly journals Naturally Occurring Radioactive Materials in Bracelets and Necklaces: Radiological Risk Evaluation

2021 ◽  
Vol 18 (21) ◽  
pp. 11170
Author(s):  
Halmat Jalal Hassan ◽  
Suhairul Hashim ◽  
Noor Zati Hani Abu Hanifah ◽  
Sib Krishna Ghoshal ◽  
Mohamad Syazwan Mohd Sanusi ◽  
...  
Keyword(s):  
Effective Dose ◽  
Gamma Ray ◽  
Annual Effective Dose ◽  
Threshold Model ◽  
Negative Ions ◽  
Radioactive Material ◽  
Gamma Ray Spectrometry ◽  
Radiological Risk ◽  
Naturally Occurring ◽  
Dose Conversion Coefficient

A particular category of jewelry is one involving bracelets and necklaces that are deliberately made to contain naturally occurring radioactive material (NORM)—purveyors making unsubstantiated claims for health benefits from the release of negative ions. Conversely, within the bounds of the linear no-threshold model, long-term use presents a radiological risk to wearers. Evaluation is conducted herein of the radiological risk arising from wearing these products and gamma-ray spectrometry is used to determine the radioactivity levels and annual effective dose of 15 commercially available bracelets (samples B1 to B15) and five necklaces (samples N16 to N20). Various use scenarios are considered; a Geant4 Monte Carlo (Geant4 MC) simulation is also performed to validate the experimental results. The dose conversion coefficient for external radiation and skin equivalent doses were also evaluated. Among the necklaces, sample N16 showed the greatest levels of radioactivity, at 246 ± 35, 1682 ± 118, and 221 ± 40 Bq, for 238U, 232Th, and 40K, respectively. For the bracelets, for 238U and 232Th, sample B15 displayed the greatest level of radioactivity, at 146 ± 21 and 980 ± 71 Bq, respectively. N16 offered the greatest percentage concentrations of U and Th, with means of 0.073 ± 0.0002% and 1.51 ± 0.0015%, respectively, giving rise to an estimated annual effective dose exposure of 1.22 mSv, substantially in excess of the ICRP recommended limit of 1 mSv/year.

scholarly journals The naturally occurring radioactivity of ‘scalar energy’ pendants and concomitant radiation risk

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0250528
Author(s):  
Halmat Jalal Hassan ◽  
Suhairul Hashim ◽  
Mohamad Syazwan Mohd Sanusi ◽  
Mohamad Hidayat Jamal ◽  
Sitti Asmah Hassan ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Radiation Risk ◽  
Organ Dose ◽  
Consumer Products ◽  
Radioactive Material ◽  
Gamma Ray Spectrometry ◽  
The Public ◽  
Naturally Occurring ◽  
Naturally Occurring Radioactive Material ◽  
K Activity

Forming part of a study of radiological risk arising from use of radioactive consumer products, investigation is made of pendants containing naturally occurring radioactive material. Based on use of gamma-ray spectrometry and Monte Carlo (MC) simulations, the study investigates commercially available ‘scalar energy pendants’. The doses from these have been simulated using MIRD5 mathematical phantoms, evaluation being made of dose conversion factors (DCFs) and organ dose. Metallic pendants code MP15 were found to contain the greatest activity, at 7043 ± 471 Bq from 232Th, while glass pendants code GP11 were presented the greatest 238U and 40K activity, at 1001 ± 172 and 687 ± 130 Bq respectively. MP15 pendants offered the greatest percentage concentrations of Th, Ce, U and Zr, with means of 25.6 ± 0.06, 5.6 ± 0.005, 1.03 ± 0.04 and 28.5 ± 0.08 respectively, giving rise to an effective dose of 2.8 mSv for a nominal wearing period of 2000 h. Accordingly, these products can give rise to annual doses in excess of the public limit of 1 mSv.

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