Age-dependent dose and health risk due to intake of uranium in drinking water from Jaduguda, India

Health risk implications due to uranium content in drinking water sources from the tectonically active zone of Garhwal Himalaya, India

Uranium is omnipresent in the earth's crust, and its high concentration in the water poses a different type of health risk to humans. In view of this, water samples were collected from several locations in the Uttarkashi district region of Uttarakhand, India. The collected water samples were analyzed using an LED Fluorimeter. The range of the uranium concentrations in the collected water samples was found to be 0.01-3.48 μg l-1 (ppb) with an AM (Arithmetic Mean) of 0.31 μg l-1 (ppb). The Pearson's r between uranium and some physicochemical parameters (pH, temperature and Total Dissolve Solids) was 0.10, 0.008 and 0.04, respectively. The calculated values of excess lifetime cancer risk, lifetime average daily dose, and hazard quotient were found to be well within the safe limit as suggested by many agencies. The Annual Effective Dose (AED) received by the different age groups was also found within the safe limit of 100 μSv y-1 recommended by the World Health Organization (WHO).

Appraisal of age-dependent geogenic radiation exposure and carcinogenic risks in the groundwater of Sevathur mine region, Pambar River basin, South India

This study investigates groundwater uranium contamination and radiological risks in a part of Pambar River basin, South India, a region with significant geogenic radiation influenced by carbonatite rock formations. Uranium concentrations ranged from 5.8 to 240.8 μg L⁻¹ , with 35 % of samples exceeding the WHO limit of 30 μg L⁻¹ . Annual effective doses varied from 7.22 to 604.36 μSv y⁻¹ , posing higher risks to infants. Despite these findings, cancer mortality and morbidity risks remained below the permissible thresholds, with values of 6.29 × 10-5 and 9.15 × 10-5, respectively. A strong correlation between uranium and total dissolved solids (TDS) highlights the influence of geogenic and anthropogenic factors. Petrological and geochemical analyses revealed uranium-rich pyrochlore minerals in carbonatite rocks, with an average uranium concentration of 14.08 mg kg⁻¹ . This study emphasizes the need for proactive groundwater monitoring and management in uranium-affected regions, providing insights into radiological health risks and geogenic contamination processes.

Risk assessment of uranium in water sources near coal mines and in human organs of Shahdol District, Madhya Pradesh, using biokinetic modelling

This study concentrated on determining the levels of uranium present in drinking water samples obtained from various locations throughout the Shahdol district in Madhya Pradesh, India. In this assessment a LED fluorimeter Quantalase (LF-2a) was utilized. Uranium, being a radioactive substance, can be hazardous to health when consumed in significant quantities over extended durations. The study found that the average uranium concentration was 167.91 µg/L. 82% of samples exceeded recommended limits, emphasizing the essential aspect of this study. The study utilizes the age-specific biokinetic model developed by the International Commission on Radiological Protection to examine uranium distribution across various organs. Using dosimetric model, the study provides a comprehensive health risk analysis by assessing the chemical toxicity and the radiation dosages received by particular organs. Longitudinal studies on uranium distribution across different organs and tissues showed that the kidneys, liver, non-exchangeable bone volume, and soft tissues are the primary locations where uranium accumulates.

Transfer factors of naturally occurring radionuclides from soil-to-rice cultivated in Bangladesh and associated health implications

This study investigates the uptake of naturally occurring radionuclides (226Ra, 232Th, and 40K) from soil by rice plants in extensively cultivated regions in Bangladesh. It also evaluates the potential radiation risks associated with rice consumption by the Bangladeshi populace. High purity germanium (HPGe) gamma-ray spectrometry was employed to measure the concentrations of radionuclides in both soil and rice samples. For 40K, our results agree with the International Atomic Energy Agency's (IAEA) published value; however, the transfer factors (TF) for the other two radionuclides differ considerably. Despite the fact that the IAEA based its publication of TFs for 226Ra and 232Th on clay soil, the majority of the soil profile in the present study was silty clay with a little alkalinity. Moreover, the data obtained may have been impacted by the growing seasons, cultivation methods, and soil fertility. Additionally, the annual effective dose due to the ingestion of radioactivity resulting from rice consumption was evaluated and the results agree with UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation), 2000. With a few exceptions, the excess lifetime cancer risk (ELCR) values for 226Ra, 232Th, and 40K were below the globally average permissible level (1 × 10-3). In light of this, the current study indicates that consuming rice does not pose an immediate health risk to the general public. By studying TFs among various rice varieties and geographical areas, scientists can develop models to forecast the possible radiation exposure from rice consumption and pinpoint activities or areas that require additional attention.

Tritium contents in drinking and surface seawaters before the nuclear power plant planned in Sinop (Türkiye) and their radiological risks on human population

This study aims to determine the background levels of tritium radioisotope in drinking and seawater samples of Sinop province before the nuclear power plant was established in Sinop. In this context, a total of 174 water samples were collected, these are as follows: nine drinking water samples from the Sinop center and districts and 165 seawater samples from the seacoast from Samsun to Kastamonu. Tritium concentrations in the collected water samples were measured by the liquid scintillation counter. The minimum detectable activity for the method used was found to be 1.48 Bq/L. The tritium concentrations of the seawater and drinking water samples were found in the range of Collapse

Key Words Collapse

MESH Headings

• Adult
• Child
• Infant
• Humans
• Tritium
• Nuclear Power Plants
• Drinking Water
• Turkey

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Grants Collapse

Affiliation(s)

Serdar Dizman Department of Physics, Faculty of Arts and Sciences, Recep Tayyip Erdogan University, Rize 53100, Türkiye E-mail:
Feyza Zeynep Aşık Institute of Graduate Studies, Recep Tayyip Erdogan University, Rize 53100, Türkiye
Ali Erdem Özçelik Department of Landscape and Architecture (Geomatics Engineer), Faculty of Engineering and Architecture, Recep Tayyip Erdogan University, Rize 53100, Türkiye
Recep Keser Department of Basic Sciences, Faculty of Engineering, Samsun University, Samsun 55100, Türkiye
Filiz Korkmaz Görür Department of Physics, Faculty of Arts and Science, Bolu Abant İzzet Baysal University, Bolu 14100, Türkiye

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Evaluation of transfer factors of 226Ra, 232Th, and 40K radionuclides from soil to grass and mango in the northern region of Bangladesh

Bangladesh is a rapidly developing country, which is vulnerable to various types of pollution due to the large-scale industrial and associated human activities that might potentially affect the locally harvested foodstuffs. Therefore, the transfer factor is an essential tool to assess the safety of foodstuffs due to the presence of natural radioactivity in environmental matrix and/or strata. This is a first study of its kind conducted in a well-known region for mango farming in Bangladesh, measuring the uptake of naturally occurring radioactive materials (NORMs) by grass and mango from soil to assess the ingestion doses to humans. The HPGe gamma-ray detector was used to determine the concentrations of NORMs in samples of soil (20), grass (10), and mango (10), which were then used to calculate the transfer factors of soil to grass and soil to mango. Average activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K in associated soil samples (47.27 ± 4.10, 64.49 ± 4.32, 421.60 ± 28.85) of mango and ²²⁶Ra and ²³²Th in associated soil samples (45.07 ± 3.93, 52.17 ± 3.95) of grass were found to exceed the world average values. The average transfer factors (TFs) for mango were obtained in the order of ⁴⁰K(0.80) > ²²⁶Ra (0.61) > ²³²Th (0.31), and for grass, it shows the order of ⁴⁰K (0.78) > ²³²Th (0.64) > ²²⁶Ra (0.56). However, a few values (3 mango samples and 3 grass samples) of the estimated TFs exceeded the recommended limits. Moreover, Bangladesh lacks the transfer factors for most of the food crops; therefore, calculation of TFs in the major agricultural products is required all over Bangladesh, especially the foodstuffs produced near the Rooppur Nuclear Power Plant, which is scheduled to be commissioned in 2023.

Radiological dose and associated risk due to 210Po in commercial inter-tidal bivalves of southwest (Arabian Sea) coast of India

The activity concentration of ²¹⁰Po was determined in edible tissues of commercial bivalves on the southwest coast of India. The ²¹⁰Po activity ranged from 38.3 ± 6.9 Bq kg^-1 to 91.2 ± 18.6 Bq kg^-1. The annual committed effective dose (ACED) and lifetime carcinogenic risk (LCR) were calculated for different age groups to determine the potential health risk associated with bivalve consumption. The average ACED ranged from 81.5 to 194.1 μSv y^-1, with the 10th and 95th percentiles being 68 and 261 μSv y^-1, respectively. Lifelong mortality risk (LMTR) values ranged from 1.2 × 10^-3 to 2.9 × 10^-3, while lifetime morbidity risk (LMBR) values ranged from 1.9 × 10^-6 to 4.9 × 10^-6. The effective dose was found to be within the UNSCEAR limits.

Radioactive releases from the nuclear power sector and implications for child health

Although radioactivity is released routinely at every stage of nuclear power generation, the regulation of these releases has never taken into account those potentially most sensitive-women, especially when pregnant, and children. From uranium mining and milling, to fuel manufacture, electricity generation and radioactive waste management, children in frontline and Indigenous communities can be disproportionately harmed due to often increased sensitivity of developing systems to toxic exposures, the lack of resources and racial and class discrimination. The reasons for the greater susceptibility of women and children to harm from radiation exposure is not fully understood. Regulatory practices, particularly in the establishment of protective exposure standards, have failed to take this difference into account. Anecdotal evidence within communities around nuclear facilities suggests an association between radiation exposure and increases in birth defects, miscarriages and childhood cancers. A significant number of academic studies tend to ascribe causality to other factors related to diet and lifestyle and dismiss these health indicators as statistically insignificant. In the case of a major release of radiation due to a serious nuclear accident, children are again on the frontlines, with a noted susceptibility to thyroid cancer, which has been found in significant numbers among children exposed both by the 1986 Chornobyl nuclear accident in Ukraine and the 2011 Fukushima-Daiichi nuclear disaster in Japan. The response among authorities in Japan is to blame increased testing or to reduce testing. More independent studies are needed focused on children, especially those in vulnerable frontline and Indigenous communities. In conducting such studies, greater consideration must be applied to culturally significant traditions and habits in these communities.

Assessment of U and As in groundwater of India: A meta-analysis

More than 2.5 billion people depend upon groundwater worldwide for drinking, and giving quality water has become one of the great apprehensions of human culture. The contamination of Uranium (U) and Arsenic (As) in the groundwater of India is gaining global attention. The current review provides state-of-the-art groundwater contamination with U and As in different zones of India based on geology and soil texture. The average concentration of U in different zones of India was in the order: West Zone (41.07 μg/L) > North Zone (37.7 μg/L) > South Zone (13.5 μg/L)> Central Zone (7.4 μg/L) > East Zone (5.7 μg/L) >Southeast Zone (2.4 μg/L). The average concentration of As in groundwater of India is in the order: South Zone (369.7 μg/L)>Central Zone (260.4 μg/L)>North Zone (67.7 μg/L)>East Zone (60.3 μg/L)>North-east zone (9.78 μg/L)>West zone (4.14 μg/L). The highest concentration of U and As were found in quaternary sediments, but U in clay skeletal and As in loamy skeletal. Results of health risk assessment showed that the average health quotient of U in groundwater for children and adults was less than unity. In contrast, it was greater than unity for As posing a harmful impact on human health. This review provides the baseline data regarding the U and As contamination status in groundwater of India, and appropriate, effective control measures need to be taken to control this problem.

Quantitative appraisal of spatiotemporal uranium distribution, quality of groundwater, and associated risks in Kapurthala, Jalandhar, and Hoshiarpur districts of northern Punjab, India

Groundwater samples from Kapurthala (45), Jalandhar (70), and Hoshiarpur (70) districts from northern Punjab, India, were studied for seasonal variation (pre-monsoon and post-monsoon) of uranium distribution and physicochemical parameters, quality and suitability for drinking purposes, source apportionment, and health risks. The average uranium concentration (in μg L^-1) in Kapurthala, Jalandhar, and Hoshiarpur districts was 12.7, 18.8, and 7.0, respectively, in pre-monsoon and 8.0, 17.3, and 5.6, respectively, in post-monsoon. In both seasons, uranium concentration was below WHO limit (30 μg L^-1) in more than 90% of groundwater samples, and it was found to exhibit positive correlation majorly with TDS, EC, and total alkalinity. Principal component analysis revealed dissolution of rocks/minerals contributing to mineralization of associated aquifers in addition to some anthropogenic activities such as excessive application of fertilizers/pesticides and dumping of domestic waste followed by their seepage into the groundwater table. All groundwater samples fall in very good to good drinking groundwater quality and its quality is more improved in post-monsoon season owing to dilution of various inorganic salts during groundwater recharge in monsoon season. Average Hazard Index (HI) values due to ingestion of U, F^-, and NO₃^- via drinking water for both adults and children were found to be marginally greater than safe limit of 1 with major contribution from F^-. It is advisable to local government/public that regular monitoring of groundwater and proper management policies or strategies should be adopted followed by their implementation to control groundwater pollution in three districts.

Hydrogeochemical Processes Governing Uranium Mobility: Inferences from the Anthropogenically Disturbed, Semi-arid Region of India

Khetri Copper Belt, Rajasthan, is anthropogenically active and geologically belongs to the Delhi super-group. A study was designed to understand the geochemical processes controlling the elemental mobility in the groundwater. Sampling sites were divided into three zones, i.e. copper, quartzite and granite mine zones depending on the type of mineral excavated. A total of 32 representative groundwater samples were collected and analysed for heavy metals and radionuclide (U) using ICP-MS. A maximum U concentration (average 87 µgL^-1) is observed in the quartzite mine zone, and minimum (average 13 µgL^-1) is found in the copper mine zone samples. A high concentration of U (maximum of 430 µgL^-1) in groundwater is attributed to mineral dissolution due to geogenic and anthropogenic activities. Despite the presence of Jaspura and Gothra granitoid in the copper mine zone, the abundance of U is low suggesting the scavenging of U by sulphides or iron oxides. Additionally, at the confluence of two geological groups, Fe concentration is found high with a low concentration of U which further confirms scavenging of U. It is evident from the results that in the absence of iron-bearing sulphides, U concentration in groundwater would be very high compared to the current concentration. It also indicates low concentration of U in the copper mine zone is due to dissolution of Fe sulphide-rich waste. The present study recommends further research to understand the feasibility of mining waste for the removal of U contamination from groundwater.

Committed effective dose and lifetime cancer risk due to ingestion of natural radionuclides in grains grown in an area of high background radiation

The current study aimed at estimating committed effective dose and cancer risk due to the intake of K-40, Ra-226, Ra-228 and Th-228 present in grains grown in an HBRA. The highest activity concentrations found were (606.2 ± 25.13), (8.07 ± 6.37), (10.01 ± 1.45), (43.97 ± 5.54) Bq.kg^-1 for K-40, Ra-226, Ra-228 and Th-228, respectively. The committed effective dose estimated was 0.5 mSv.y^-1, and the estimated cancer risk suggested that uninterrupted and unrestricted consumption of beans grown in this HBRA is not desirable.

Tritium concentrations and consequent doses in bottled natural and mineral waters sold in Turkey and Azerbaijan

In this study, tritium levels in commercially sold bottled natural and mineral waters in Turkey and Azerbaijan were determined. Tritium measurements were performed using Liquid Scintillation Counter (PerkinElmer TriCarb 2910 TR). 16 natural and 11 mineral samples from Turkey and 7 natural and 8 mineral samples from Azerbaijan, for a total of 42 commercially sold water samples were analyzed. The Minimum Detectable Activity (MDA) value for the method used was found as 1.69 Bq L^-1. In total, 7 of the natural water samples and 8 of the mineral water samples were found to be below the MDA value. The average activity concentrations in natural and mineral water samples were found as 2.23 ± 0.90 Bq L^-1 and 2.51 ± 0.90 Bq L^-1 for Turkey and 2.69 ± 0.91 Bq L^-1 and 2.43 ± 0.89 Bq L^-1 for Azerbaijan, respectively. In addition, annual effective dose rates and lifetime cancer risk values for the water samples were calculated. These radiological parameters were compared with the values recommended by international organizations. The results demonstrated that consumption by humans of the studied waters would not constitute any health risks in terms of tritium.

Assessment of the Levels of Pollution and of Their Risks by Radioactivity and Trace Metals on Marine Edible Fish and Crustaceans at the Bay of Bengal (Chattogram, Bangladesh)

Marine environmental pollution is a longstanding global problem and has a particular impact on the Bay of Bengal. Effluent from different sources directly enters rivers of the region and eventually flows into the Bay of Bengal. This effluent may contain radioactive materials and trace metals and pose a serious threat to the coastal environment, in addition to aquatic ecosystems. Using gamma spectrometry and atomic absorption spectrometry, a comprehensive study was carried out on the radioactivity (226Ra, 232Th, 40K, and 137Cs) and trace metal (Cd, Pb, Zn, Cu, Ni, Fe, Mn, and Cr) concentrations, respectively, in fish and crustacean species collected from the coastal belt of the Bay of Bengal (Chattogram, Bangladesh). The analysis showed a noticeable increment in the levels of different radioactive pollutants in the marine samples, although the consumption of the studied fish and crustacean species should be considered safe for human health. Anthropogenic radionuclide (137Cs) was not detected in any sample. Furthermore, the metal concentrations of a small number of trace elements (Pb, Cd, Cr) were found to be higher in most of the samples, which indicates aquatic fauna are subject to pollution. The estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TR) were calculated and compared with the permissible safety limits. It was found that consuming the seafood from the Bay of Bengal may cause adverse health impacts if consumption and/or means of pollution are not controlled.

Estimation of uranium in groundwater and assessment of age-dependent radiation dose in Nalbari district of Assam, India

Uranium concentration has been estimated in 31 groundwater samples collected from the Nalbari district of Assam in pre-monsoon and post-monsoon season. Fourteen other water quality parameters have also been monitored to study their correlation with uranium. The uranium concentration varies from 0.3 to 7.1 µg/L with the mean value of 2.15 µg/L in pre-monsoon and 0.6–10.3 µg/L with the mean value of 2.75 µg/L in the post-monsoon season. The higher concentration of uranium in post-monsoon may be ascribed to the dissolution of uranium from soil sediments in the rainy season. It has been observed that the uranium content in both seasons is far lower than the WHO (2011) permissible limit of 30 µg/L. In both seasons, nitrate, sulphate, and especially phosphate show a positive correlation with uranium, which may be due to different agricultural activities. Agricultural nitrate and phosphate fertilization might be the carrier of uranium in groundwater through dissolution. For all life stage groups, the annual effective dose was appeared to be far below the WHO (2011) prescribed limit of 100 µSv/y. In consideration to adults, the ingestion dose for infants was turned out to be higher. The carcinogenic and non-carcinogenic risk was less than the permissible limits for both children and adults. Both dose value and risk indices were found higher in the post-monsoon season.

Distribution and Geochemical Controls of Arsenic and Uranium in Groundwater-Derived Drinking Water in Bihar, India

Chronic exposure to groundwater containing elevated concentrations of geogenic contaminants such as arsenic (As) and uranium (U) can lead to detrimental health impacts. In this study, we have undertaken a groundwater survey of representative sites across all districts of the State of Bihar, in the Middle Gangetic Plain of north-eastern India. The aim is to characterize the inorganic major and trace element aqueous geochemistry in groundwater sources widely used for drinking in Bihar, with a particular focus on the spatial distribution and associated geochemical controls on groundwater As and U. Concentrations of As and U are highly heterogeneous across Bihar, exceeding (provisional) guideline values in ~16% and 7% of samples (n = 273), respectively. The strongly inverse correlation between As and U is consistent with the contrasting redox controls on As and U mobility. High As is associated with Fe, Mn, lower Eh and is depth-dependent; in contrast, high U is associated with HCO₃⁻, NO₃⁻ and higher Eh. The improved understanding of the distribution and geochemical controls on As and U in Bihar has important implications on remediation priorities and selection, and may contribute to informing further monitoring and/or representative characterization efforts in Bihar and elsewhere in India.

Study of Primordial 226Ra, 228Ra, and 40K Concentrations in Dietary Palm Dates and Concomitant Radiological Risk

The presence of natural radionuclides in the food chain point to a need to assess concentration levels and concomitant radiological risk. Highly popular and forming a staple part of the diet in North Africa, the Arabian Peninsula, and West Asia, palm dates growing naturally there have even greater marketability than simple satisfaction of domestic demand, the palm dates representing a valuable export item. Accurate knowledge of the levels of natural radioactivity in the fruit is thus of importance. In this study, using high-purity germanium gamma-ray spectrometry, quantification has been made of natural radionuclide concentrations in imported dates originating from Iran, Saudi Arabia, and Tunisia. Sample analyses reveal respective mean activity concentrations of 1.4 ± 0.3, 0.8 ± 0.4, and 186 ± 9 Bq kg dry weight for Ra, Ra, and K. For each nuclide, the mean concentration varies little between the dates of the three represented regions. The estimated committed effective dose resulting from the consumption of date fruits for a typical adult was found to be 29.9 μSv y, well below the global internal dose of 290 μSv y assessed by the United Nations Scientific Committee on the Effects of Atomic Radiation to be due to food and water intake. Similarly, the excess lifetime cancer risk due to naturally occurring radioactive material exposure via date fruit consumption is seen to be below the International Commission on Radiological Protection cancer risk factor of 2.5 × 10 based on the additional annual dose limit of 1 mSv for a member of the general public. The results show no significant uptake in the analyzed date fruits.

Uranium distribution in groundwater and assessment of age dependent radiation dose in Amritsar, Gurdaspur and Pathankot districts of Punjab, India

A comprehensive study of seasonal variation of uranium distribution in groundwater of Amritsar, Gurdaspur and Pathankot districts of Punjab, India and assessment of associated radiological risks, chemical risks and effective radiation dose for different age groups, was conducted to determine its health impact on humans residing in these regions. Physicochemical parameters such as pH, EC, TDS, total hardness and contents of various anions such as carbonates/bicarbonates, chlorides, fluorides, nitrates, sulphates and phosphates in groundwater were also analysed to determine correlation between groundwater chemistry and uranium distribution. The average values of uranium concentration in ground water samples of Amritsar, Gurdaspur and Pathankot districts were found to be 8.6 μg L^-1, 4.3 μg L^-1 and 3.0 μg L^-1, respectively, in pre-monsoon and 8.8 μg L^-1, 4.9 μg L^-1 and 3.4 μg L^-1, respectively, in post-monsoon. The uranium concentration in majority of the ground water samples was found to be below the permissible limit of 30 μg L^-1 recommended by World Health Organization (WHO, 2011). In all three districts, TDS, EC and bicarbonates were found to have positive correlation with observed uranium contents in both seasons. The annual effective dose due to ingestion of uranium through drinking water was found to be less than the prescribed limit of 100 μSv y^-1 given by WHO (2004). Radiological and chemical toxicity risk assessment of uranium in groundwater was also carried out and found to be within the permissible values of 1.67 × 10^-4 and 4.53 μg kg^-1 day^-1 respectively, recommended by Atomic Energy Regulatory Board (AERB, 2004).

Recent aspects of uranium toxicology in medical geology

Uranium (U) is a chemo-toxic, radiotoxic and even a carcinogenic element. Due to its radioactivity, the effects of U on humans health have been extensively investigated. Prolonged U exposure may cause kidney disease and cancer. The geological distribution of U radionuclides is still a great concern for human health. Uranium in groundwater, frequently used as drinking water, and general environmental pollution with U raise concerns about the potential public health problem in several areas of Asia. The particular paleo-geological hallmark of India and other Southern Asiatic regions enhances the risk of U pollution in rural and urban communities. This paper highlights different health and environmental aspects of U as well as uptake and intake. It discusses levels of U in soil and water and the related health issues. Also described are different issues of U pollution, such as U and fertilizers, occupational exposure in miners, use and hazards of U in weapons (depleted U), U and plutonium as catalysts in the reaction between DNA and H₂O_2, and recycling of U from groundwater to surface soils in irrigation. For use in medical geology and U research, large databases and data warehouses are currently available in Europe and the United States.

Natural radionuclide dose and lifetime cancer risk due to ingestion of fish and water from fresh water reservoirs near the proposed uranium mining site

Ten sampling locations in Nagarjuna Sagar Dam have been selected to assess the suitability of the reservoir water for human consumption. The sediment, water, and fish samples were collected and analyzed for radionuclide (²³⁸U, ²³²Th, ²¹⁰Po, ²²⁶Ra, ²¹⁰Pb) and physicochemical parameters like pH, TOC, total hardness, alkalinity, DO, cation exchange capacity, and particle size. The spatial variations among the radionuclides (²³⁸U, ²³²Th, ²¹⁰Po, ²²⁶Ra, ²¹⁰Pb) in water and bottom sediments of Nagarjuna Sagar Dam were determined. The uranium concentration in the sediment and water was in BDL (<0.5 ppb). The maximum permissible limits in water samples of the analyzed radionuclides are ²³⁸U-10 Bq/l, ²¹⁰Po-0.1 Bq/l, ²²⁶Ra-1 Bq/l, and ²¹⁰Pb-0.1 Bq/l. The radionuclides in our water samples were approximately 50 times far below the recommended limit. The ingestion of water and fish would not pose any significant radiological impact on health or cancer risk to the public, implicating that the fishes from Nagarjuna Sagar Dam reservoir are safe for human consumption except the fisherman community.

Evaluation of radionuclides transfer from soil-to-edible flora and estimation of radiological dose to the Malaysian populace

Malaysia, a rapidly growing industrial country, is susceptible to pollution via large-scale industrial engagements and associated human activities. One particular concern is the potential impact upon the quality of locally resourced vegetables, foodstuffs that contain important nutrients necessary for good health, forming an essential part of the Malaysian diet. As a part of this, it is of importance for there to be accurate knowledge of radioactive material uptake in these vegetables, not least in respect of any public health detriment. Herein, using HPGe γ-ray spectrometry, quantification has been performed of naturally occurring radionuclides in common edible vegetables and their associated soils. From samples analyses, the soil activity concentration ranges (in units of Bq/kg) for (226)Ra, (232)Th and (40)K were respectively 1.33-30.90, 0.48-26.80, 7.99-136.5 while in vegetable samples the ranges were 0.64-3.80, 0.21-6.91, 85.53-463.8. Using the corresponding activities, the transfer factors (TFs) from soil-to-vegetables were estimated, the transfers being greatest for (40)K, an expected outcome given the essentiality of this element in support of vigorous growth. The TFs of (226)Ra and (232)Th were found to be in accord with available literature data, the values indicating the mobility of these radionuclides to be low in the studied soils. Committed effective dose and the associated life-time cancer risk was estimated, being found to be below the permissible limit proposed by UNSCEAR. Results for the studied media show that the prevalent activities and mobilities pose no significant threat to human health, the edible vegetables being safe for consumption.

Measurement of radioactivity and heavy metal levels in edible vegetables and their impact on Kuala Selangor communities of Peninsular Malaysia

Vegetable is an essential daily diet item for the people of Malaysia. This work addressed the radiation and heavy metal exposure scenarios through the consumption of vegetables. Kuala Selangor is located in Sungai Selangor estuary in the west coast of Peninsular Malaysia, which is susceptible to pollution load due to the presence of large-scale industrial and human activities. Radioactivity and heavy metals level in human diet is of particular concern for the assessment of possible radiological and chemical hazards to human health. Therefore, a comprehensive study was carried out to determine the radioactivity levels ((226)Ra, (228)Ra and (40)K) and heavy metal concentrations (Cr, As, Cd, Mn, Mg, Al, Sr, Rb, Sb, Ba, Hg, Fe, Ni, Zn, Cu, Bi and Pb) in 10 varieties of vegetable collected from different farmlands in Kuala Selangor region. The committed doses for (226)Ra, (228)Ra and (40)K due to consumption of vegetables were found 16.6±1.3, 23.6±1.7 and 58±5 µSv y(-1), respectively, with a total of 98±8 µSv y(-1). This dose imposes no significant threat to human health. The estimated cancer risk shows that probability of increase in cancer risk from daily intake of vegetables is only a minor fraction of International Commission on Radiological Protection values. The concentrations of heavy metal were below the daily intake recommended by the international organisations.

Assessment of Radiation and Heavy Metals Risk due to the Dietary Intake of Marine Fishes (Rastrelliger kanagurta) from the Straits of Malacca

The environment of the Straits of Malacca receives pollution as a result of various industrial and anthropogenic sources, making systematic studies crucial in determining the prevailing water quality. Present study concerns concentrations of natural radionuclides and heavy metals in marine fish (Rastrelliger kanagurta) collected from the Straits of Malacca, since aquatic stock form an important source of the daily diet of the surrounding populace. Assessment was made of the concentrations of key indicator radionuclides (226Ra, 232Th, 40K) and heavy metals (As, Mn, Fe, Cr, Ni, Zn, Cu, Co, Sr, Al, Hg and Pb) together with various radiation indices linked to the consumption of seafish. The annual effective dose for all detected radionuclides for all study locations has been found to be within UNSCEAR acceptable limits as has the associated life-time cancer risk. The overall contamination of the sampled fish from heavy metals was also found to be within limits of tolerance.