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Radon (222Rn), a radioactive and gaseous progeny of Uranium (238U) decay series, accounts for almost 50% of the total background radiation in our dwelling environment. Inhalation and ingestion of radon in excessive amounts pose serious health effects to humans. The first-ever measurement of radon concentration in commercial bottled water available in Dhaka city and deep well water samples from the campus of the University of Dhaka was carried out using the RAD7 Radon monitoring system. The concentration of radon in the bottled water ranged from 0.11 Bq/L to 1.30 Bq/L with a mean of 0.59 Bq/L, and the deep well water showed a mean of 4.88 Bq/L with a range of 3.02 Bq/L to 5.98 Bq/L. All twenty-five samples of water had radon concentrations within the recommended limits of USEPA and WHO. The mean annual effective doses from radon in bottled water and deep well water were evaluated to be 0.126 µSv/y and 12.481 µSv/y, respectively. Although the calculated doses indicate the least potential risk according to WHO and UNSCEAR, however, it is expected that the present results play an important role in setting up a national guideline for radon in drinking water, and the monitoring of radon for the safety of public health. [ABSTRACT FROM AUTHOR]

This study determines the prevailing concentrations of 222Rn in twenty groundwater samples and primordial radionuclides in twelve soil samples collected from the surrounding area of the Rooppur Nuclear Power Plant (RNPP) in Bangladesh. The mean concentration of 222Rn, 226Ra, 232Th and 40K in the studied samples was found to be 4.42 ± 2 Bq/L (Water), 25.2 ± 5.3, 23.9 ± 6.3 and 317.1 ± 31.4 Bq kg−1 (Soil) respectively. Associated health hazards were estimated and compared with the respective safety limits recommended by international organizations. The present results may serve as the base values of naturally occurring radioactive materials in the vicinity of the RNPP in Bangladesh. [ABSTRACT FROM AUTHOR]

Radon (222Rn), an inert gas, is considered a silent killer due to its carcinogenic characteristics. Dhaka city is situated on the banks of the Buriganga River, which is regarded as the lifeline of Dhaka city because it serves as a significant source of the city's water supply for domestic and industrial purposes. Thirty water samples (10 tap water from Dhaka city and 20 surface samples from the Buriganga River) were collected and analyzed using a RAD H2O accessory for 222Rn concentration. The average 222Rn concentration in tap and river water was 1.54 ± 0.38 Bq/L and 0.68 ± 0.29 Bq/L, respectively. All the values were found below the maximum contamination limit (MCL) of 11.1 Bq/L set by the USEPA, the WHO-recommended safe limit of 100 Bq/L, and the UNSCEAR suggested range of 4–40 Bq/L. The mean values of the total annual effective doses due to inhalation and ingestion were calculated to be 9.77 μSv/y and 4.29 μSv/y for tap water and river water, respectively. Although all these values were well below the permissible limit of 100 μSv/y proposed by WHO, they cannot be neglected because of the hazardous nature of 222Rn, especially considering their entry to the human body via inhalation and ingestion pathways. The obtained data may serve as a reference for future 222Rn-related works. [ABSTRACT FROM AUTHOR]

The study has been carried out to measure the activity concentration of natural and anthropogenic radionuclides in fifteen(15) soil samples of Natore, Kushtia and Pabna district, which are around the 30 km peripheral area of Rooppur Nuclear Power Plant, by gamma ray spectrometry system using a High Purity Germanium (HPGe) detector. It is found that the activity concentration of 226Ra, in the collected sample was from 3.52 Bq/kg to 28.5 Bq/kg with the average value of 12.42 Bq/kg. For 232Th, the range was from 4.18 Bq/kg to 34.5 Bq/kg with the average value of 12.6 Bq/kg. Finally, the activity concentration of 40K, in the collected sample was in the range of 84 Bq/kg to 345 Bq/kg, and the average value was 198.9 Bq/kg. The absorbed dose rate (D) was found to be in the range of 4.59 nGy/h to 40.93 nGy/h with the mean value 21.3 nGy/h. The annual effective dose (E) was in the range of 0.006 mSv/yr to 0.152 mSv/yr with an average of 0.033 mSv/yr. The radium equivalent activity was in the range from 10.02 Bq/kg to 89 Bq/kg with an average of 44.99 Bq/kg. The external hazard index (Hex) was found to be in the range of 0.027 to 0.242 with the mean value of 0.121 and the internal hazard index (Hin) was found to be in the range of 0.044 to 0.302 with the mean value of 0.156. All the values are much below the recommended limit by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 35 Bq/kg for 226Ra, 30 Bq/kg for 232Th and 400 Bq/kg for 40K. According to international and national regulation, the annual dose to members of the public, 1 mSvy-1 and Hex & Hin must be lower than unity. Moreover, no artificial radioactivity was found in the soil samples of this study area. This research concludes that the found values are within the permissible limits as required by the Nuclear Safety and Radiation Control(NSRC) Rules-1997 of Bangladesh and International Atomic Energy Agency(IAEA) Safety Standards- General Safety Requirements (GSR): Part-3. [ABSTRACT FROM AUTHOR]

Sixteen samples in three categories vegetables, cereals (rice, wheat, maize, pulse) and powdered milk were collected from local markets (Dhaka city) in Bangladesh and analyzed by using High Purity Germanium (HPGe) Detector for the assessment of natural and artificial radioactivity. In vegetables (potato, raw banana, giant taro, red amaranth), the average activity concentrations of 232Th, 226Ra, and 40K were found to be 37.82±11.57, 54.93±9.98 and 617.43±65.69 Bqkg-1 respectively, for cereals (rice, wheat, maize, pulse) 24.01±3.67, 31.46±4.00 and 474.83±27.68 Bqkg-1 respectively and for milk samples 15.01±3.65, 26.73±6.77 and 494.21±38.71 Bqkg-1 respectively. The average values of outdoor annual effective dose were found to be 92.18, 61.19 and 52.37μSvy-1 in vegetables, cereals and milk samples respectively. No artificial radionuclide was found in any of these samples. The average value of radium equivalent activity in all samples was 113.89 Bqkg-1 which was less than maximum permissible value 370 Bqkg-1. The values of external hazard indices for vegetables, cereals and milk samples varied from 0.31 to 0.66, 0.17 to 0.40 and 0.11 to 0.36 respectively which is less than unity in all samples that indicate the non-hazardous nature of the samples. The average values of annual effective ingestion dose rate from foods (for adult) were 274.33 μSvy-1, 533.60μSvy-1, and 132.73μSvy-1for 232Th, 226Ra and 40K respectively. These data would be useful to establish a baseline for natural radioactivity concentrations in food items consumed in Bangladesh. [ABSTRACT FROM AUTHOR]

The radioactivity concentrations of 24 samples of soil and sand sediments from Cox's Bazar were determined using high purity germanium detector. The results of 226Ra, 232Th and 40K in the soil samples were found to vary from 15.34 ± 1.66 to 33.70 ± 2.08 Bq/kg, 30.09 ± 3.62 to 58.06 ± 4.23 Bq/kg and 379.99 ± 33.43 to 755.26 ± 38.03 Bq/kg, respectively. For sand samples the activity concentrations were between 8.98 ± 1.49 to 31.33 ± 2.04 Bq/kg, 16.82 ± 3.24 to 63.28 ± 4.37 Bq/kg and 252.42 ± 31.72 to 565.72 ± 35.78 Bq/kg, respectively, for sediment samples values were 13.90 ± 1.64 to 38.41 ± 2.19 Bq/kg, 37.94 ± 3.82 to 51.92 ± 4.11 Bq/kg and 367.70 ± 33.28 to 665.05 ± 36.97 Bq/kg, 367.70 ± 33.28 to 665.05 ± 36.97 Bq/kg, respectively. The absorbed dose rate of soil, sand and sediment samples were found as 79.98, 77.17, and 57.86 nGy/h, respectively. Outdoor annual effective doses were 0.49, 0.47 and 0.36 mSv/y. [ABSTRACT FROM AUTHOR]

A small part of the palaeo beach formation extending along the south-eastern fringe of Bangladesh was selected as study area. The sandy beach formation, enriched with heavy mineral sands containing 232Th-bearing monazite, is covered by a thin layer of top soil. Activity concentrations of natural and artificial radionuclides (238U, 226Ra, 232Th, 40K and 137Cs), outdoor and indoor annual effective dose rates and the radiation hazard indices were determined in the soil. The radionuclides, investigated by direct gamma-ray spectrometry using HPGe detector, showed that mean activity concentrations of 226Ra, 238U, 232Th, 40K and 137Cs in soils were 254.53±6.66, 193.95±7.23, 362.18±6.45, 135.79±24.63 and 2.21±0.49 Bq kg−1 respectively. The mean value of radium equivalent activity, external and internal hazards, outdoor absorbed dose rate and total annual effective dose rate were 783.24 Bq Kg−1, 2.12 and 2.80, 354.32 nGyh−1 and 2.52 mSv y−1, respectively, which exceed the average worldwide limit and may pose a radiological threat to inhabitants. [ABSTRACT FROM PUBLISHER]

With the use of traditional thermoluminescence dosimeters (TLDs), this study was carried out to determine the effective dose and its trend in order to ensure radiation safety at interventional cardiology practices in Bangladeshi hospitals. Between 2015 and 2019, 1015 radiation workers in Bangladesh who were under observation for their personal dose equivalent were reported. There were 417 physicians among them, while the remaining personnel included radiological technologists, physicists, and other medical staff members. To measure the exposure dose, a conventional TLD-100 (LiF:Mg, Ti) was used. A Harshaw TLD reader (Model 4500) was used to read the TLDs on a quarterly basis. All of the monitored workers, who made up around 19.11% of the total, had ionizing radiation exposure below the limit established by international organizations. The Mann–Kendall trend test and Sen's slope estimator were also applied to the annual collective effective doses, and it showed a decreasing trend over the time frame. The current state of occupational exposure and its trends show that most workplaces have effective radiation protective measures in place. [ABSTRACT FROM AUTHOR]