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Fulltext Field demonstration of irradiated sodium alginate as tea production booster

Hossain MA, Islam JMM, Hoque MM, Nahar S, Khan MA

Heliyon, 2021 Jan;7(1):e05881.
PMID: 33458447 DOI: 10.1016/j.heliyon.2020.e05881

Sodium alginate oligomers were tested for tea plant growth promoter and anti-fungal agent in this experiment. Sodium alginate solutions were irradiated by Co-60 gamma radiation with different radiation doses to produce the oligomers. Irradiated solutions were then diluted into 150, 300 and 500 ppm prior to foliar application. Solutions were applied through foliar spraying at 7 days interval and the best response of tea plants in terms of various attributes were recorded. Tea buds were collected in 10 days of interval and the growth attributes like- total number of buds, fresh weight of buds, average leaf area and weight per bud, weight of made tea etc. were calculated. The experiment was continued up to 12 weeks and the attributes were averaged to get results per plucking. 12 kGy radiation doses along with 300ppm solution showed the best results and about 36% increase in productivity was found based on the fresh weight of buds. Total fungal count in tea leaves was also found to be reduced greatly. Based on the present study, irradiated sodium alginate could be used as safe and environmentally friendly agent to increase tea production.

Matched MeSH terms: Cobalt Radioisotopes
Fulltext Primary thyroid lymphoma: A rare malignancy in the head and neck

Mohd Shaiful Nizam Mamat Nasir, Bathma Dhevi Susibalan, Muhammad Nasri Abu Bakar, Suhaimi Yusof, Arfahiza Selimin, Kahairi Abdullah, et al.

Archives of Orofacial Sciences, 2018;13(2):1-4.
MyJurnal

Primary thyroid lymphoma is a relatively uncommon pathology of the thyroid gland that mainly occurs in elderly females. We describe a rare case of B-cell thyroid lymphoma in a young healthy male. It is an important diagnosis to be considered in patients presenting with a rapidly enlarging neck mass as its management is different from other differentiated thyroid carcinoma which require total thyroidectomy plus adjuvant radioactive iodine ablation. Our report emphasizes the need for clinical awareness leading to early detection, followed by early multidisciplinary management.

Matched MeSH terms: Iodine Radioisotopes
Fulltext Natural radioactivity content and radionuclides lechability of bricks containing industrial waste

Zalina Laili, Mohd Zaidi Ibrahim, Muhamat Omar

Jurnal Sains Nuklear Malaysia, 2013;25(2):50-60.
MyJurnal

A study has been carried out using a gamma-ray spectrometric system to determine the natural
radioactivity level in bricks made from industrial waste and their associated radiation hazard.
Brick-1 and brick-2 contained waste from coal power plant and granite industry, respectively. The
leachability of radionuclides from these bricks was also investigated. The activity concentration
values of 226Ra,
228Ra,
232Th, and 40K are 64.25, 63.15, 67.9 and 254.19 Bq/kg, respectively in brick-
1, and 193, 164.48, 164.63 and 1348.75 Bq/kg, respectively in brick-2. The radiation hazard
indexes such as radium equivalent activities (Raeq), representative level index (Iγr), external hazard
index (Hex) and internal hazard index (Hin) were calculated and compared with the internationally
approved values. Results indicate that brick-1 showed less radiological hazard than brick-2. This
suggested that brick-1 could be used in building construction without exceeding the proposed
criterion level.The leachability of 226Ra for bricks showed the activity concentration slightly
exceeded 1 Bq/L which is the limit generally used for industrial wastewater.

Matched MeSH terms: Radioisotopes
Fulltext Anthropogenic airborne depositions of 210Po, 210Pb and 210Po/210Pb in the mosses and surface soils at the vicinity of a coal-fired power

Nita Salina Abu Bakar, Zal U’yun Wan Mahmood, Ahmad Saat, Abdul Kadir Ishak

Jurnal Sains Nuklear Malaysia, 2014;26(1):2-17.
MyJurnal

Anthropogenic airborne depositions of 210Po,
210Pb and 210Po/210Pb in the mosses and surface soils
collected at the vicinity of a coal-fired power plant were studied. The purpose of the study was to
determine activity concentrations of 210Po,
210Pb and 210Po/210Pb for assessing their variation
accumulation in the mosses and surface soils collected at the vicinity of a coal-fired power plant.
Other purposes were to determine their concentration factor (CF) in relation to track the potential
source of those radionuclides and to identify most suitable moss species as a biological indicator
for atmospheric deposition contaminants. In this study, different species of moss Leucobryum
aduncum, Campylopus serratus, Syrrhopodon ciliates and Vesicularia montagnei were collected in
May 2011 at the area around 15 km radius from Tanjung Bin coal-fired power plant located in
Pontian, Johor. The activity concentrations of 210Po,
210Pb and 210Po/210Pb in mosses were in the
range of 76.81 ± 4.94 – 251.33 ± 16.33 Bq/kg dry wt., 54.37 ± 3.38 – 164.63 ± 11.64 Bq/kg dry wt.
and 1.10 – 2.00, respectively. Meanwhile the ranges for those radionuclides in the surface soil
were 33.53 ± 2.10 – 179.67 ± 12.15 Bq/kg dry wt., 20.55 ± 1.33 – 106.62 ± 6.64 Bq/kg dry wt. and
1.61 – 2.44, respectively. Corresponding high ability of Leucobryum aduncum to accumulate more
210Po and 210Pb, wide geographical distribution, most abundant and high CF, therefore, the
findings can be concluded this species was the most suitable as a biological indicator for
atmospheric deposition contaminants such as 210Po and 210Pb. Furthermore, it is clear the
accumulation of 210Po and 210Pb in mosses might be supplied from various sources of atmospheric
deposition such as coal-fired power plant operation, industrial, agriculture and fertilizer activities,
burned fuel fossil and forest; and other potential sources. Meanwhile, the

Matched MeSH terms: Radioisotopes
Fulltext Quantification of coral sperm collected during a synchronous spawning event

Teo A, Guest JR, Neo ML, Vicentuan K, Todd PA

PeerJ, 2016;4:e2180.
PMID: 27478697 DOI: 10.7717/peerj.2180

Most studies of coral reproductive biology to date have focused on oocyte numbers and sizes. Only one (ex situ) study has enumerated sperm numbers, even though these data have multiple potential applications. We quantified total coral sperm and eggs per gamete bundle collected from six species in situ during a synchronous spawning event in Singapore. Egg-sperm bundles were captured midwater as they floated towards the surface after being released by the colony. For each sample, a semi-transparent soft plastic bottle was squeezed and released to create a small suction force that was used to 'catch' the bundles. This technique provided several advantages over traditional methods, including low cost, ease of use, no diving prior to the night of collection needed, and the ability to target specific areas of the colony. The six species sampled were Echinophyllia aspera, Favites abdita, F. chinensis, Merulina ampliata, M. scabricula and Platygyra pini. The mean number of sperm packaged within one egg-sperm bundle ranged from 2.04 × 10(6) to 1.93 × 10(7). The mean number of eggs per egg-sperm bundle ranged from 26.67 (SE ± 3.27) to 85.33 (SE ± 17.79). These data are critical for fertilisation success models, but the collection technique described could also be applied to studies requiring in situ spawning data at the polyp level.

Matched MeSH terms: Selenium Radioisotopes
Fulltext General purpose nuclear irradiation chamber

Nurul Fadzlin Hasbullah, Nuurul Iffah Che Omar, Nahrul Khair Alang Md Rashid, Jaafar Abdullah

Journal of Nuclear and Related Technologies, 2013;2013(2):70-76.
MyJurnal

Nuclear technology has found a great need for use in medicine, industry, and research. Smoke
detectors in our homes, medical treatments and new varieties of plants by irradiating its seeds are just a few examples of the benefits of nuclear technology. Portable neutron source such as Californium-252, available at Industrial Technology Division (BTI/PAT), Malaysian Nuclear Agency, has a 2.645 year half-life. However, 252 Cf is known to emit gamma radiation from the source. Thus, this chamber aims to provide a proper gamma shielding for samples to distinguish the use of mixed neutron with gamma-rays or pure neutron radiation. The chamber is compatible to be used with other portable neutron sources such as 241 Am-Be as well as the reactor TRIGA PUSPATI for higher neutron dose. This chamber was designed through a collaborative effort of Kulliyyah Engineering, IIUM with the Bahagian Teknologi Industri (BTI) team, Agency Nuklear Malaysia.

Matched MeSH terms: Radioisotopes
Fulltext Radioactive disequilibrium and total activity concentration of norm waste

Omar, M., Hamzah, M.S., Wood, A.K.

Journal of Nuclear and Related Technologies, 2008;2008(2):47-56.
MyJurnal

A study to measure the concentrations of long-lived radionuclides of the uranium and thorium series in naturally occurring radioactive materials (NORM) wastes was carried out using gamma spectrometry and neutron activation analysis methods. It was found that radionuclides in the NORM wastes of the oil/gas production and ores/minerals processing industries were not in equilibrium. The 226 Ra/ 238 U and 228 Ra/ 232 Th ratios were between 0.001 and 2220 indicating that the concentrations of daughters radionuclides ( 226 Ra, 228 Ra) were very low or very high compared to the parent radionuclides ( 238 U, 232 Th) in the NORM wastes.

Matched MeSH terms: Radioisotopes
Fulltext Analysis of the concentrations of natural radionuclides in rivers in Kota Tinggi district, Malaysia

Ahmad Taufek Abdul Rahman, Ahmad Termizi Ramli, Abd. Khalik Wood

Journal of Nuclear and Related Technologies, 2004;2004(1):34-45.
MyJurnal

Environmental radiation protection program is important in the effort to limit radiation dose to the public to be as low as reasonably achievable. As water is an important factor of transfer of radionuclide to human, therefore it is important to measure natural radionuclide concentrations in rivers. 20 water samples were collected randomly from the main rivers in Kota Tinggi district. The water samples collected were analysed using ICP-MS technique to determine uranium, thorium and potassium concentration in river water. Radionuclide concentrations obtained were compared with the terrestrial gamma radiation dose rate measured in the area. Significance of the results obtained is discussed.

Matched MeSH terms: Radioisotopes
Fulltext Measurement of some water quality parameters related to natural radionuclides in aqueous environmental samples from former tin mining lake

Zaini Hamzah, Masitah Alias, Ahmad Saat, Abdul Kadir Ishak

Journal of Nuclear and Related Technologies, 2011;2011(2):49-59.
MyJurnal

The issue of water quality is a never ended issue and becoming more critical when considering the presence of natural radionuclides. Physical parameters and the levels of radionuclides may have some correlation and need further attention. In this study, the former tin mine lake in Kampong Gajah was chosen as a study area for its past historical background which might contribute to attenuation of the levels of natural radionuclides in water. The water samples were collected from different lakes using water sampler and some in-situ measurement were conducted to measure physical parameters as well as surface dose level. The water samples were analyzed for its gross alpha and gross beta activity concentrations using liquid scintillation counting and in-house cocktail method. Gross alpha and beta analyzed using in-house cocktail are in the range of 3.17 to 8.20 Bq/L and 9.89 to 22.20 Bq/L; 1.64 to 8.78 Bq/L and 0.22 to 28.22 Bq/L, respectively for preserved and un-preserved sample. The surface dose rate measured using survey meter is in the range of 0.07 to 0.21 μSv/h and 0.07 to 0.2 μSv/h for surface and 1 meter above the surface of the water, respectively.

Matched MeSH terms: Radioisotopes
Fulltext Measurement of gross alpha, gross beta, radon and radium activity concentrations in aqueous samples using liquid scintillation technique

Zaini Hamzah, Masitah Alias, Siti Afiqah Abdul Rahman, Mohamed Kassim, Ahmad Saat, Abdul Kadir Ishak

Journal of Nuclear and Related Technologies, 2011;2011(2):85-93.
MyJurnal

Recently, Malaysia has taken a positive step toward providing a better water quality by introducing more water quality parameters into its Water Quality Standard. With regard to the natural radionuclides that may present in the water, 3 parameters were introduced that is gross alpha, gross beta and radium which need to be measured and cannot exceed 0.1, 1.0 and 1.0 Bq/L respectively. This study was conducted to develop a more practical method in measuring these parameters in aqueous environmental samples. Besides having a lot of former tin mining areas, some part of Malaysia is located on the granitic rock which also contributes to a certain extent the amount of natural radionuclides such as uranium and thorium. For all we know these two radionuclides are the origin of other radionuclides being produced from their decay series. The State of Kelantan was chosen as the study area, where the water samples were collected from various part of the Kelantan River. 25 liters of samples were collected, acidify to pH 2 and filtered before the analysis. Measurement of these parameters was done using liquid scintillation counter (LSC). The LSC was set up to
the optimum discriminator level and counting was done using alpha-beta mode. The results show that gross alpha and beta can be measured using scintillation cocktail and radium and radon using extraction method. The results for gross alpha, gross beta, 222Ra and 226Ra are 0.39-6.42, 0.66-16.18, 0.40-4.65 and 0.05-0.56 Bq/L. MDA for gross alpha, gross beta and radium is 0.03, 0.08 and 0.00035 Bq/L respectively.

Matched MeSH terms: Radioisotopes
Follicular carcinoma thyroid

Dharmalingam SK, Narasimha K

Med J Malaya, 1972 Sep;27(1):73-6.
PMID: 4264829
Matched MeSH terms: Iodine Radioisotopes
Fulltext Optical Properties and Conductivity of PVA-H3PO4 (Polyvinyl Alcohol-Phosphoric Acid) Film Blend Irradiated by γ-Rays

Susilawati S, Prayogi S, Arif MF, Ismail NM, Bilad MR, Asy'ari M

Polymers (Basel), 2021 Mar 28;13(7).
PMID: 33800592 DOI: 10.3390/polym13071065

This study assesses the optical properties and conductivity of PVA-H3PO4 (polyvinyl alcohol-phosphoric acid) polymer film blend irradiated by gamma (γ) rays. The PVA-H3PO4 polymer film blend was prepared by the solvent-casting method at H3PO4 concentrations of 75 v% and 85 v%, and then irradiated up to 25 kGy using γ-rays from the Cobalt-60 isotope source. The optical absorption spectrum was measured using an ultraviolet-visible spectrophotometer over a wavelength range of 200 to 700 nm. It was found that the absorption peaks are in three regions, namely two peaks in the ultraviolet region (310 and 350 nm) and one peak in the visible region (550 nm). The presence of an absorption peak after being exposed to hυ energy indicates a transition of electrons from HOMO to LUMO within the polymer chain. The study of optical absorption shows that the energy band gap (energy gap) depends on the radiation dose and the concentration of H3PO4 in the polymer film blend. The optical absorption, absorption edge, and energy gap decrease with increasing H3PO4 concentration and radiation dose. The interaction between PVA and H3PO4 blend led to an increase in the conductivity of the resulting polymer blend film.

Matched MeSH terms: Cobalt Radioisotopes
18F-labeled Bisphosphonate as an Alternative Candidate to the Gold Standard[18F]sodium fluoride ([18F]NaF) for PET Bone Imaging

Hassan H, Othman MF, Razak HRA

Curr Med Imaging, 2021;17(11):1271-1275.
PMID: 33593263 DOI: 10.2174/1573405617666210216091202

Bone metastases are a common source of malignancy in the skeleton and occur much more often than primary bone cancer. Several works were being performed to identify early markers for bone metastasis and novel drug targets to improve patients' quality of life. As some concerns exist with the [18F]sodiumfluoridein positron emission tomography (PET) bone imaging, there has been an increase in the number of targeted radiopharmaceutical markers for bone metastases imaging in its competitor, 68Ga. Since 18F properties are superior to those of 68Ga, there is a distinct motivation for developing 18F radiopharmaceuticals for bone metastases imaging.

Matched MeSH terms: Fluorine Radioisotopes
68Ga-prostate specific membrane antigen-11 PET/CT versus multiparametric MRI in the detection of primary prostate cancer: A systematic review and head-to-head comparative meta-analysis

Ren X, Nur Salihin Yusoff M, Hartini Mohd Taib N, Zhang L, Wang K

Eur J Radiol, 2024 Jan;170:111274.
PMID: 38147764 DOI: 10.1016/j.ejrad.2023.111274

PURPOSE: The goal of this study was to evaluate the effectiveness of two diagnostic methods, 68Ga-PSMA-11 PET/CT and mpMRI, in detecting primary prostate cancer without limitations on the Gleason score.
METHODS: We conducted a comprehensive literature review, searching databases such as PubMed, Embase, and Web of Science until June 2023. Our objective was to identify studies that compared the efficacy of 68Ga-PSMA-11 PET/CT and mpMRI in detecting primary prostate cancer. To determine heterogeneity, the I2 statistic was used. Meta-regression analysis and leave-one-out sensitivity analysis were conducted to identify potential sources of heterogeneity.
RESULTS: Initially, 1286 publications were found, but after careful evaluation, only 16 studies involving 1227 patients were analyzed thoroughly. The results showed that the 68Ga-PSMA-11 PET/CT method had a pooled sensitivity and specificity of 0.87 (95 % CI: 0.80-0.92) and 0.80 (95 % CI: 0.69-0.89), respectively, for diagnosing prostatic cancer. Similarly, the values for mpMRI were determined as 0.84 (95 % CI: 0.75-0.92) and 0.74 (95 % CI: 0.61-0.86), respectively. There were no significant differences in diagnostic effectiveness observed when comparing two primary prostate cancer methodologies (pooled sensitivity P = 0.62, pooled specificity P = 0.50). Despite this, the funnel plots showed symmetry and the Egger test results (P values > 0.05) suggested there was no publication bias.
CONCLUSIONS: After an extensive meta-analysis, it was found that both 68Ga-PSMA-11 PET/CT and mpMRI demonstrate similar diagnostic effectiveness in detecting primary prostate cancer. Future larger prospective studies are warranted to investigate this issue further.

Matched MeSH terms: Gallium Radioisotopes
Fulltext Neutron Activated Samarium-153 Microparticles for Transarterial Radioembolization of Liver Tumour with Post-Procedure Imaging Capabilities

Hashikin NA, Yeong CH, Abdullah BJ, Ng KH, Chung LY, Dahalan R, et al.

PLoS One, 2015;10(9):e0138106.
PMID: 26382059 DOI: 10.1371/journal.pone.0138106

Samarium-153 (153Sm) styrene divinylbenzene microparticles were developed as a surrogate for Yttrium-90 (90Y) microspheres in liver radioembolization therapy. Unlike the pure beta emitter 90Y, 153Sm possess both therapeutic beta and diagnostic gamma radiations, making it possible for post-procedure imaging following therapy.

Matched MeSH terms: Radioisotopes/therapeutic use*; Yttrium Radioisotopes/therapeutic use
Systematic investigation on the validity of partition model dosimetry for90Y radioembolization using Monte Carlo simulation

Hashikin NAA, Yeong CH, Guatelli S, Abdullah BJJ, Ng KH, Malaroda A, et al.

Phys Med Biol, 2017 Aug 22;62(18):7342-7356.
PMID: 28686171 DOI: 10.1088/1361-6560/aa7e5b

We aimed to investigate the validity of the partition model (PM) in estimating the absorbed doses to liver tumour ([Formula: see text]), normal liver tissue ([Formula: see text]) and lungs ([Formula: see text]), when cross-fire irradiations between these compartments are being considered. MIRD-5 phantom incorporated with various treatment parameters, i.e. tumour involvement (TI), tumour-to-normal liver uptake ratio (T/N) and lung shunting (LS), were simulated using the Geant4 Monte Carlo (MC) toolkit. 108track histories were generated for each combination of the three parameters to obtain the absorbed dose per activity uptake in each compartment ([Formula: see text], [Formula: see text], and [Formula: see text]). The administered activities, A were estimated using PM, so as to achieve either limiting doses to normal liver, [Formula: see text] or lungs, [Formula: see text] (70 or 30 Gy, respectively). Using these administered activities, the activity uptake in each compartment ([Formula: see text], [Formula: see text], and [Formula: see text]) was estimated and multiplied with the absorbed dose per activity uptake attained using the MC simulations, to obtain the actual dose received by each compartment. PM overestimated [Formula: see text] by 11.7% in all cases, due to the escaped particles from the lungs. [Formula: see text] and [Formula: see text] by MC were largely affected by T/N, which were not considered by PM due to cross-fire exclusion at the tumour-normal liver boundary. These have resulted in the overestimation of [Formula: see text] by up to 8% and underestimation of [Formula: see text] by as high as -78%, by PM. When [Formula: see text] was estimated via PM, the MC simulations showed significantly higher [Formula: see text] for cases with higher T/N, and LS ⩽ 10%. All [Formula: see text] and [Formula: see text] by MC were overestimated by PM, thus [Formula: see text] were never exceeded. PM leads to inaccurate dose estimations due to the exclusion of cross-fire irradiation, i.e. between the tumour and normal liver tissue. Caution should be taken for cases with higher TI and T/N, and lower LS, as they contribute to major underestimation of [Formula: see text]. For [Formula: see text], a different correction factor for dose calculation may be used for improved accuracy.

Matched MeSH terms: Yttrium Radioisotopes/therapeutic use*
Elevated concentrations of naturally occurring radionuclides in heavy mineral-rich beach sands of Langkawi Island, Malaysia

Khandaker MU, Asaduzzaman K, Sulaiman AFB, Bradley DA, Isinkaye MO

Mar Pollut Bull, 2018 Feb;127:654-663.
PMID: 29475708 DOI: 10.1016/j.marpolbul.2017.12.055

Study is made of the radioactivity in the beach sands of Langkawi island, a well-known tourist destination. Investigation is made of the relative presence of the naturally occurring radionuclide 40K and the natural-series indicator radionuclides 226Ra and 232Th, the gamma radiation exposure also being estimated. Sample quantities of black and white sand were collected for gamma ray spectrometry, yielding activity concentration in black sands of 226Ra, 232Th and 40K from 451±9 to 2411±65Bqkg-1 (mean of 1478Bqkg-1); 232±4 to 1272±35Bqkg-1 (mean of 718Bqkg-1) and 61±6 to 136±7Bqkg-1 (mean of 103Bqkg-1) respectively. Conversely, in white sands the respective values for 226Ra and 232Th were appreciably lower, at 8.3±0.5 to 13.7±1.4Bqkg-1 (mean of 9.8Bqkg-1) and 4.5±0.7 to 9.4±1.0Bqkg-1 (mean of 5.9Bqkg-1); 40K activities differed insubstantially from that in black sands, at 85±4 to 133±7Bqkg-1 with a mean of 102Bqkg-1. The mean activity concentrations of 226Ra and 232Th in black sands are comparable with that of high background areas elsewhere in the world. The heavy minerals content gives rise to elevated 226Ra and 232Th activity concentrations in all of black sand samples. Evaluation of the various radiological risk parameters points to values which in some cases could be in excess of recommendations providing for safe living and working. Statistical analysis examines correlations between the origins of the radionuclides, also identifying and classifying the radiological parameters. Present results may help to form an interest in rare-earth resources for the electronics industry, power generation and the viability of nuclear fuels cycle resources.

Matched MeSH terms: Radioisotopes/analysis*
Geological influence on the activity concentration of terrestrial radionuclides 226Ra, 232Th and 40K in the Jos Plateau, Nigeria

Tela Abba H, Wan Hassan WMS, Saleh MA, Aliyu AS, Ramli AT, Abdulsalam H

Isotopes Environ Health Stud, 2018 Oct;54(5):522-534.
PMID: 29847152 DOI: 10.1080/10256016.2018.1474879

The Jos Plateau has been reported to have elevated levels of natural background radiation. A few earlier studies have measured the levels of natural radioactivity for specific locations in the area. Our interest is to investigate how geology of the study area influences the activity concentrations of natural radionuclides. Thus, the activity concentrations of terrestrial radionuclides in soil samples collected across the geological formations of the Jos Plateau were determined by gamma spectrometry technique. The mean activity concentrations of 226Ra, 232Th and 40K were found to exceed their corresponding world reference values of 35, 40 and 400 Bq kg-1, respectively. Data were compared using statistical methods, analysis of variance (ANOVA) and post hoc tests. The results revealed in some instances significant influences of geological types on the activity concentrations in the area. The spatial distribution maps of activity concentrations of 226Ra, 232Th and 40K were geostatistically interpolated by ordinary Kriging method using ArcGIS software.

Matched MeSH terms: Potassium Radioisotopes/analysis*
Determination of 226Ra, 232Th and 40K in teeth by use of gamma spectroscopy

Salih NF

Isotopes Environ Health Stud, 2019 Mar;55(1):80-91.
PMID: 30241441 DOI: 10.1080/10256016.2018.1520708

This study entails the measurement of the specific activity of natural radionuclides (226Ra, 40K and 232Th) in 18 tooth samples obtained from the clinic of the Universiti Sains Malaysia (USM), Penang, by using an HPGe detector. The specific activity of 226Ra, 40K and 232Th was measured to estimate the hazard index of the radionuclides, radium equivalent activities (Raeq), external, internal hazard indices (Hex, Hin), and absorbed dose (Dout, Din). The maximum values of concentration of 226Ra, 232Th and 40K in the tooth samples were found to be 60.82, 60.29 and 594.22 Bq kg-1, respectively. Maximum values of Raeq, Hex, Hin, Dout and Din were found to be 192.78 Bq kg-1, 0.520, 0.685, 89.29 and 169.81 nGy h-1, Iγ and Iα as 0.702 and 0.304, respectively. The results were lower than the average world value (UNSCEAR). In addition, a strong correlation was found between the concentrations of 226Ra and Raeq, between energy and net area, as well as between radionuclides (226Ra, 40K and 232Th) in tooth samples and age of volunteers. This study showed that the concentrations and hazard indices of tooth samples are below the recommended safe levels; therefore, the study area is considered safe in terms of radiological health hazards.

Matched MeSH terms: Potassium Radioisotopes/analysis*
TERRESTRIAL RADIONUCLIDES IN SURFACE (DAM) WATER AND CONCOMITANT DOSE IN METROPOLITAN KUALA LUMPUR

Khandaker MU, Uwatse OB, Bin Shamsul Khairi KA, Faruque MRI, Bradley DA

Radiat Prot Dosimetry, 2019 Dec 31;185(3):343-350.
PMID: 30806465 DOI: 10.1093/rpd/ncz018

Batu Dam is of considerable importance to the metropolis of Kuala Lumpur, its existence and the quality assessment of its waters being essential in helping to maintain the lives of a large sector of the Malaysian population. Concerning the level of naturally occurring radioactivity contained within its waters, a well characterised HPGe γ-ray technique has been used in making measurements of the concentrations of primordial radionuclides in samples of surface water from the Dam. Based on the mean individual daily consumption of dam water, estimation has been made of the concomitant radiation dose. Activity concentrations, in units of Bq l-1, have been found to be in the range 2.4-3.2 for 226Ra, 1.1-1.3 for 232Th and 22.7-40.7 for 40K, in line with literature data for surface waters. The total annual ingestion dose for infants (<1 y) and adolescents (12-17 y) are found to be significant and greater than the World Health Organization recommended maximum dose of 0.1 mSv y-1 from the imbibing of drinking water. However, the Dam water does not pose a threat to public health, the Dam water not being used as the sole source of drinking water. Noting that this is the only known study of water from Batu Dam, the reported levels allow for evaluation of future changes in the natural radioactivity profile.

Matched MeSH terms: Potassium Radioisotopes/analysis*

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