Eye radiation dose from breast cancer screening using full field digital mammography and digital breast tomosynthesis: A phantom study

INTRODUCTION

The eye lens is recently classified as one of the most radiosensitive tissues by the International Commission on Radiological Protection (ICRP), and it has been suggested that the eye lens receives radiation dose during mammography due to scatter radiation. The aim of this study was to investigate the radiation dose received by the lens of the clients' eye from Full Field Digital Mammography (FFDM) and Digital Breast Tomosynthesis (DBT) screening.

METHODS

The eye radiation dose received by ATOM dosimetry phantom was estimated with thermo-luminescent dosemeters (TLDs). One TLD was utilised for each eye. A breast phantom was exposed for four-view screening mammography using 16 FFDM machines and one DBT machine. The breast phantom was exposed three times for each mammographic position and an average TLD dose reading was considered to minimise random error.

RESULTS

For four-view FFDM screening, the phantom eye radiation dose ranges from 0.013 mGy to 0.029 mGy with a mean±sd of 0.019 ± 0.005 mGy. A higher eye radiation dose of 0.041 mGy was recorded from four-view DBT screening. The statistical analysis demonstrated that the eye lens radiation dose is strongly and significantly correlated to breast organ dose and X-ray tube voltage.

CONCLUSION

The phantom eye lens was exposed to scatter radiation from FFDM and DBT screening. The measured dose via the four-view DBT screening was higher than the four-view FFDM screening, but sits below the internationally acceptable ranges. If the findings of our paper hold true in practice, then the risk to the lens of the eyes for women attending breast screening is acceptable.

IMPLICATIONS FOR PRACTICE

The new lens radiation dose levels recommended by the ICRP necessitate the reevaluation of eye radiation dose from different radiographic examinations, especially those used for screening purpose where healthy individuals involved.

Evaluation of natural radioactivity in soils of Konya (Turkey) and estimation of radiological health hazards

Surface soil samples were collected from Konya, Turkey and natural activity concentrations were determined using the ɤ-ray spectroscopy system with HPGe detector. The activity concentrations of 226Ra, 232Th and 40K were found to vary from 14.07 ± 0.71 Bq kg-1 dw to 67.27 ± 1.62 Bq kg-1 dw, 10.19 ± 2.60 Bq kg-1 dw to 46.09 ± 0.76 Bq kg-1 dw and 107.87 ± 13.32 Bq kg-1 dw to 605.95 ± 11.34 Bq kg-1 dry weight (dw), respectively. The radiological hazard parameters such as Raeq, D, AEDE, ELCR, AGDE, Hex, Hin, and Iɤ evaluated the radiological risk for the public and environment. The mean values of D, AEDE and ELCR are lower than the world average value of 57 nGy h-1, 70 μSv y-1, 0.29 × 10-3 respectively. The activity concentration distribution maps of 226Ra, 232Th and 40K and the radiological maps of the radiological hazard parameters were plotted using the Surfer programme. Cluster analysis was carried out to indicate the similarity between the variables.

Distribution dynamics and descriptive statistical analysis of radionuclides in the farmland soils near mining areas in Southwestern Nigeria

Human exposure to ionizing radiation in the environment is mainly due to naturally occurring radionuclides in the soils, building materials and rocks, but the level may vary depending on the anthropogenic activities prevalent in each location. Presently, in Nigeria, there are concerns due to environmental health implications of all sorts of mineral mining and processing spreading across the southwestern states of the country. This work determines the activity concentrations of naturally occurring radionuclide materials (NORMs) in the farmland soil with the aim of evaluating the radiation hazards. A total of 200 composite soil samples were taken from five states in the southwest of Nigeria, close to active mining sites at the root (0.2 m) and at deep planting zones (0.5 m) for analysis by gamma-ray spectrometry using NaI(Tl) detector. The activity concentrations of natural radionuclides in the composite soil samples were determined to vary in the order of ⁴⁰ K > ²³²Th > ²²⁶Ra/²³⁸U for all locations. In contrast to the other locations, Olode and Igbokoda had average radium equivalent activities (Ra_eq) to be 1.6 and 1.8 times, respectively, higher than the reference limit of 370 Bqkg^-1. The estimated excess life cancer risk values were lower than the 0.29 × 10^-3 global average value for soil by United Nations on Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and International Commission on Radiological Protection (ICRP). Negative and low skewness values of 0.61 and 1.20 were obtained for ⁴⁰ K in Itagunmodi, and also 0.47 and 0.66 for ²³²Th were obtained in Sagamu. The kurtosis analysis of the activity concentrations was low and negative for soil at Itagunmodi for ⁴⁰ K and ²²⁶Ra/²³⁸U; Olode for ⁴⁰ K and ²³²Th; and Igbokoda for ²²⁶Ra/²³⁸U and ²³²Th where mining activities are commonly practiced. The variation in the results has been attributed to different agriculture practices and artisanal mining operations in each location.

Assessment of hazardous radionuclide emission due to fly ash from fossil fuel combustion in industrial activities in India and its impact on public

Traditionally coal has been extensively used as a dominating fossil fuel in a wide range of industries due to its abundance. In India, industries like thermal power plants, cement industries, iron, and steel industries along with many captive power plants consume a huge quantity of coal each year to meet energy demand. Coal combustion releases blackish-grey colored fly ash waste is one of the most imperative sources of radionuclides like Radium (²²⁶Ra), Thorium (²³²Th), Potassium (⁴⁰K) and Uranium (²³⁸U). The estimated industrial fly ash is ∼308.416 Million Tonnes (MT) in 2019, considered as an emerging environmental problem. This study represents the first-ever radionuclide emission from Indian fly ash generated across various major industries. The results reveal that the estimated ²²⁶Ra, ²³²Th, ²³⁸U, and ⁴⁰K radionuclides were estimated to be ∼27.473 TBq, ∼44.351 TBq, ∼41.089 TBq, and ∼111.091 TBq respectively. The potential radionuclide hotspot regions across the nation are identified, which could be used as an important tool to assess its impact on the chronic exposure of millions of residents living near these sources. Cleaner or green energy could be the best alternative to combat the unseen health disaster. More effective and safe utilization of fly ash can minimize the hazardous effect of radionuclides emission.

Activity concentrations and radiological hazard assessments of 226Ra, 232Th, and 40K in soil samples of oil-producing areas of South Africa

The specific activity of natural radionuclide in soil samples of the oil-producing areas of South Africa was measured using a High Purity Germanium detector. The activity of226Ra, 232Th, and 40K in the soil range from 16.5 ± 1.3 to 64.9 ± 3.1, 16.8 ± 1.5 to 88.6 ± 1.2, 135.2 ± 17.5 to 604.8 ± 13.4 Bqkg-1 for Mossel Bay; 14.3 ± 1.2 to 48.9 ± 8.2, 22.3 ± 1.4 to 45.1 ± 3.2, 237.7 ± 10.9 to 486.5 ± 40.1 Bqkg-1 for Cape Town; 10.5 ± 1.1 to 25.8 ± 3.2, 13.1 ± 1.9 to 44.3 ± 5.2, 140.2 ± 10.9 to 229.8 ± 12.8 Bqkg-1 for Nelson Mandela Bay and 5.6 ± 2.2 to 13.1 ± 2.9, 4.5 ± 2.5 to 14.1 ± 2.7, 62.7 ± 22.6 to 126.5 ± 21.2 Bqkg-1 for Msunduzi. Most soil samples' radiological hazards were within the world average.

Distribution of natural and anthropogenic radionuclides and associated radiation indices in the Southwestern coastline of Caspian Sea

The distribution pattern of natural radionuclides (²²⁶Ra, ²³²Th, and ⁴⁰K) and anthropogenic radionuclide (¹³⁷Cs) in surface sediment samples from the southwestern coastline of the Caspian Sea were determined to estimate the radiation hazard indices using a high-purity germanium HPGe gamma-ray detector. The activity concentrations of the sediment samples ranged from 22.5 ± 1.0 to 47.4 ± 2.2 Bq kg^-1 dry weight (dw) for ²²⁶Ra, 6.5 ± 0.1 to 18.7 ± 0.7 Bq kg^-1 dw for ²³²Th, 559.9 ± 30.9 to 233.2 ± 19.4 Bq kg^-1 dw for ⁴⁰K, and 0.9 MDL (minimum detection limit) to 2.7 ± 0.1 Bq kg^-1 dw for ¹³⁷Cs. Based on the measured values, radiological risk indices were estimated. The mean values for absorbed dose rate, ambient dose equivalent rate, and excess lifetime cancer risk, were calculated as 35.7 nGy h^-1, 47.9 nSv h^-1, and 0.2, respectively.

Female astronauts: Impact of space radiation on menopause

Space travel has different effects on the reproductive capacity of women compared to men. The radiation exposure intrinsic to deep space travel causes destruction of some of a woman's primordial follicles. Data suggests that a typical Mars mission may reduce a women's ovarian reserve by about 50%. This has consequences to a woman's reproductive capacity and, more significantly, decreases the time interval to her menopause. A reduced time interval to menopause is associated with earlier mortality. Estrogen replacement therapy and cryopreservation of a female astronaut's oocytes may be used to address these issues. However, cortical tissue freezing provides advantages to more directly compensate for these workplace complications. Cortical tissue freezing especially provides advantages if there are plans to reproduce in an extraterrestrial location.

Assessment of radiation hazards from phosphate rocks, Sibaiya area, central eastern desert, Egypt

The present work used the integrated Carbone γ-ray spectrometric data and HPGe γ-ray spectrometer data to the prospect of radioactive zones at the Sibaiya area, Central Eastern Desert, Egypt. Carbone γ-ray spectrometric survey revealed ten uranium anomalies distributed along the car traverse from west to east direction have values of 240, 104, 44, 34, 150, 124, 232, 132, 60, and 90 ppm, respectively. These significant anomalies are associated mainly with phosphates mines characterized by a substantial increase of eU/eTh and eU/K ratios. Ten phosphate samples were collected from the determining anomalies. They were analyzed using the HPGe detector gamma-ray spectrometer. It was found that the results of radioelement concentrations by carborne survey agree well with that obtained by HPGe. The average activity concentration for the Sibaiya phosphate samples under study is 152.5, 947, and 33.2 Bq/kg against the worldwide accepted limit of 412, 33, and 45 Bq/kg for ⁴⁰K, ²³⁸U, and ²³²Th, respectively. The radium equivalent ranges from 499 to 3484.9 Bq/kg, which is higher than the recommended value 370 Bq/kg. The external hazard's (H_ex) calculated values range from 1.35 to 9.42 mGy/yr, and the internal hazard (H_in) ranges from 2.58 to 18.69. These indexes must be lower than unity to keep the radiation hazard insignificant. The value of the radioactivity level index (Iγ) is found to be more than unity, which varies between 1.68 and 11.63. The dose rate (D_R) ranges from 149.5 to 970 nGy/h, higher than the international mean value of 55 nGy/h. The annual effective dose ranges from 0.18 to 1.19 mSv, which less than unity in almost all values. Meanwhile, the values of activity of ²²⁶Ra ranged from 454 to 3429 Bq/kg and the mean of mass radon exhalation rate (J_m) is 6615 mBq kg^-1 h^-1 which is lower than the worldwide average.

An assessment of medical students' proficiency regarding the hazards of radiological examinations on the health of workers and patients: a cross-sectional study from Palestine

BACKGROUND

The use of radiological examination is increasing worldwide. Since radiation exposure can result in many health hazards, medical professionals, as well as medical students, should possess adequate knowledge regarding radiation and its related hazards to protect themselves and the patients. Many studies have assessed medical students' knowledge on this topic, but never in Palestine. In this study, we aimed to examine Palestinian medical students' awareness and knowledge regarding radiological examination modalities and their risks on themselves and their patients.

METHODS

This was an observational, cross-sectional, population-based study, conducted to assess the awareness of radiation exposure and its risks among Palestinian medical students. An online questionnaire was implemented on medical students at An-Najah National University. A total knowledge score that ranged from 0 to 22 was calculated for each participant, with higher scores indicating better knowledge regarding radiation doses and the related hazards.

RESULTS

Two hundred eighty and seven students participated in our study, with a response rate of 71%. The average knowledge score of the participants was 10.97 ± 4.31 out of a maximum of 22 points. Male participants and participants in advanced study years achieved better knowledge scores (p-values were 0.034 and < 0.001, respectively). Perceived radiology knowledge was significantly associated with the actual knowledge score among the participants (p-value< 0.001). Receiving radiology lectures in fourth and fifth years significantly affected the participants' knowledge score (p-values were < 0.001).

CONCLUSIONS

We found a severe lack of knowledge regarding radiation doses and related risks among medical students. Therefore, we recommend that medical schools update and supplement their curriculum regarding knowledge on radiation.

Radon exhalation study of manganese clay residue and usability in brick production

The reuse of by-products and residue streams is an important topic due to environmental and financial aspects. Manganese clay is a residue of manganese ore processing and is generated in huge amounts. This residue may contain some radionuclides with elevated concentrations. In this study, the radon emanation features and the massic exhalation rate of the heat-treated manganese clay were determined with regard to brick production. From the manganese mud depository, 20 samples were collected and after homogenization radon exhalation characteristics were determined as a function of firing temperatures from 100 to 750 °C. The major naturally occurring radionuclides ⁴⁰K, ²²⁶Ra and ²³²Th concentrations were 607 ± 34, 52 ± 6 and 40 ± 5 Bq kg^-1, respectively, comparable with normal clay samples. Similar to our previous studies a strong correlation was found between the internal structure and the radon emanation. The radon emanation coefficient decreased by ∼96% from 0.23 at 100 °C to 0.01 at 750 °C. The massic radon exhalation rate of samples fired at 750 °C reduced by 3% compared to samples fired at 100 °C. In light of the results, reusing of manganese clay as a brick additive is possible without any constraints.

Natural radioactivity assessment of surface sediments in the Yangtze Estuary

The activities of the natural radionuclides (²³⁸U, ²³²Th, ²²⁶Ra and ⁴⁰K) of the surface sediments in the Yangtze Estuary were determined and used to evaluate radiation hazards in the study area. The of activities of ²³⁸U, ²³²Th, ²²⁶Ra and ⁴⁰K ranges from 14.1 to 62.3, 26.1 to 71.9, 13.7 to 52.3, and 392 to 898Bqkg^-1, respectively, which were comparable to values of other regions in China. The activities of ²³²Th, ⁴⁰K and ²²⁶Ra were clearly different from the global recommended values. The radium equivalent activity was less than the recommended limit of 370Bqkg^-1; therefore, the sediment in this area can be safely used for reclamation. The external hazard index values were less than one. The average absorbed gamma dose rate and annual effective dose equivalent values were slightly greater than the world average value. ²²⁶Ra/²³⁸U and ²³²Th/²³⁸U ratios could potentially be applied for tracing sediment source.

Natural radioactivity level in beach sand along the coast of Xiamen Island, China

The activity concentration of (40)K, (232)Th and (226)Ra was determined in beach sand samples collected from Xiamen Island, China using gamma ray spectrometry. The activity concentrations of (40)K, (232)Th and (226)Ra in the beach sand range from 197.4 to 487.6, 6.5 to 41.4 and 7.9 to 25.7 Bq kg(-1) with the mean of 401.0, 11.3 and 14.1 Bq kg(-1), respectively, which are lower than the averages of Chinese soil and world soil. The radium equivalent activity values in all beach sand samples are lower than the recommended limit of 370 Bq kg(-1). The external hazard index values are less than unity. The outdoor air absorbed dose rate and the corresponding annual effective dose rate of beach sand investigated are lower than the worldwide average.