Distribution of natural radionuclides in NORM samples from North Abu Rusheid area, Egypt

The North Abu Rusheid area in Egypt is a well-known high background natural radiation area (HBNRA) due to the existence of naturally occurring radioactive materials (NORMs) in mylonitic rocks. In this study, 27 rock samples were selected for dose estimation studies. ²³⁸U and ²³²Th were measured using inductively coupled plasma mass spectrometry (ICP-MS) and ⁴⁰K was measured using sodium iodide (thallium) gamma-ray spectroscopy. The ranges of activity concentrations (Bq/kg) of ²³⁸U, ²³²Th and ⁴⁰K in the samples varied from 270 ± 2 to 2120 ± 29, 350 ± 2 to 1840 ± 27 and 20 ± 2 to 1390 ± 35 with mean values of 980 ± 349, 770 ± 351, and 640 ± 402 Bq/kg, respectively. The radiological hazard parameters were estimated from activity concentrations of ²³⁸U, ²³²Th and ⁴⁰K and compared to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) values. The present study revealed that the hazard parameters were several times higher than the worldwide averages. The U/Th concentration ratio ranged from 0.7 to 3 and could be attributed to the presence of kasolite, uranothorite, zircon, and columbite in mylonitic rocks. From the radiological protection viewpoint, it is necessary to monitor natural radionuclides in these rocks prior to their use in residential and commercial construction materials.

Generation of map on natural environmental background absorbed dose rate in India

A systematic mapping of natural absorbed dose rate was carried out to assess the existing exposure situation in India. The mammoth nationwide survey covered the entire terrestrial region of the country comprising of 45127 sampling grids (grid size 36 km²) with more than 100,000 data points. The data was processed using Geographic Information System. This study is based on established national and international approaches to provide linkage with conventional geochemical mapping of soil. Majority (93%) of the absorbed dose rate data was collected using handheld radiation survey meters and remaining were measured using environmental Thermo Luminescent Dosimeters. The mean absorbed dose rate of the entire country including several mineralized regions, was found to be 96 ± 21 nGy/h. The median, Geometric Mean and Geometric Standard Deviation values of absorbed dose rate were 94, 94 and 1.2 nGy/h, respectively. Among the High Background Radiation Areas of the country, absorbed dose rate varied from 700 to 9562 nGy/h in Karunagappally area of Kollam district, Kerala. The absorbed dose rate in the present nationwide study is comparable with the global database.

Dissipation kinetics of imidacloprid in cotton flower, nectariferous tissue, pollen and Apis mellifera products using QuEChERS method

BACKGROUND

Exposure of Apis mellifera to neonicotinoid insecticides is one of the factors attributed to the recent decline in A. mellifera populations resulting in economic and ecological losses due to loss of pollination services. Honey bees can get exposed to neonicotinoids like imidacloprid directly in the field at the time of application as well as during consumption of pollen and nectar from treated plants. So, the fate of imidacloprid in commodities to which honey bees get exposed needs to be overhauled.

RESULTS

Residue of imidacloprid was investigated following imidacloprid application as seed treatment (2.4 and 4.8 g a.i. kg^-1 seed) at the time of sowing and as foliar spray (17.8 and 35.6 g a.i. ha^-1 ) at 70 days after sowing when the crop was at full bloom stage.  The imidacloprid residue was below limit of quantification (LOQ) in flowers, necatariferous tissue, pollen from seed-treated cotton plants and honey collected from hives kept in plots with seed-treated cotton plants. However, average initial imidacloprid residue (2 h after spray) was 1.84 and 1.95 mg kg^-1 in flowers; 0.22 and 0.24 mg kg^-1 in nectariferous tissue; 0.88 and 0.96 mg kg^-1 in pollen collected from plants sprayed with imidacloprid @ 17.8 g a.i. ha^-1 at locations Faridkot and Bathinda, respectively. The average initial imidacloprid residue (21 days after spray) in honey collected from hives was 0.01 mg kg^-1 .

CONCLUSION

The residue in different substrates sampled from seed treated cotton plants was below LOQ. However, its foliar spray at bloom time resulted in imidacloprid residue in flower, nectariferous tissue, pollen and honey sampled from hives placed in plots. © 2021 Society of Chemical Industry.

Effectiveness of community-based treatment programs for treatment of uncomplicated severe acute malnourished children aged 6-59 months using locally produced nutrient dense foods: protocol for a multicentric longitudinal quasi-experimental study

Background

Severe acute malnutrition (SAM) is a major underlying cause of mortality among children. Around one third of the world’s acutely malnourished children live in India. The WHO recommends community-based management of acute malnutrition (CMAM) for managing children with SAM. In India, different states are implementing community-based SAM treatment programme, hereinafter called CSAM, using varieties of locally produced nutrient dense food items with different nutrient compositions. The study will assess the effectiveness of these state specific CSAM interventions.

Methods

The longitudinal quasi-experimental study will be undertaken in two purposively selected blocks of one district each in the four intervention states and one comparison state. From each state, 200 SAM children identified using weight-for-length/height z-score (WHZ) < − 3 criteria will be enrolled in the study. Their anthropometric data and skinfold thickness will be taken on admission, at sixth week and at discharge by trained field investigators. Other child details, incidence of morbidity and socio-economic details will be collected on admission. To assess food consumption pattern including consumption of locally produced nutrient dense food supplements, dietary assessment, using 24-h dietary recall will be conducted on admission, at sixth week and at discharge. In addition, body composition parameters will be assessed for a sub-set of children using bio-electrical impedance analysis on admission and at discharge to analyse changes in total body water, fat-free mass, and fat mass. Post discharge, all study participants will be followed up monthly until 6 months. Atleast 10% of the sample will be checked for quality assessment.

The study’s primary outcome is cure rate defined as children attaining WHZ ≥ -2. Secondary outcomes include mean weight gain, mean length of stay, body composition parameters, relapse and mortality rates. Additionally, process evaluation and cost effectiveness analysis will be conducted.

Discussion

There is a shortage of robust evidence regarding the effectiveness of locally produced nutrient dense food supplements provided as part of the CSAM intervention in India. This study will contribute to evidence on effective strategies to manage children with uncomplicated SAM in India. The study protocol has all necessary ethical approvals. Written informed consent will be obtained from caregivers of the children.

Trial registration

The study is registered with Clinical Trial Registration of India (Registration No.: CTRI/2020/09/028013) Date of registration 24/09/2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40795-021-00489-1.

Assessment of Cytokine and Herpesvirus Level in Peri-implantitis and Healthy Patients

BACKGROUND

The present study was conducted to assess level of cytokine and herpesvirus in peri-implantitis and healthy patients.

METHODOLOGY

Fifty patients with healthy dental implant (Group I) and dental implant with peri-implantitis (Group II) were enrolled. The level of interleukin (IL)-1 β, IL-2, IL-4, IL-6, MCP-1 and tumor necrosis factor-α (TNF-α), and herpesvirus was estimated.

RESULTS

The mean IL-1 β level was 1.54 in Group I and 5.12 in Group II, IL-2 was 0.05 in Group I and 0.02 in Group II, IL-4 was 0.018 in Group I and 0.0021 in Group II, IL-6 was 0.83 in Group I and 0.92 in Group II, MCP-1 was 64.5 in Group I and 23.1 in Group II, and TNF-alpha was 1.54 in Group I and 1.05 in Group II. There was a significant higher level of TNF-alpha in virus + patients (P < 0.05).

CONCLUSION

The cytokine level was increased in patients with peri-implantitis as compared to patients with healthy dental implants. Virus-positive patients exhibited higher cytokine levels than virus-negative patients.

Validation of QuEChERS Method for Estimation of Imidacloprid and its Metabolites in Cotton Flower, Pollen, Nectariferous Tissue and Honey

BACKGROUND

Exposure of Apis mellifera to neonicotinoid insecticides is one of the factors attributed to the recent decline in Apis mellifera populations resulting in economic and ecological losses due to loss of pollination services. Honeybees can get exposed to neonicotinoids like imidacloprid directly in the field at the time of application as well as during consumption of pollen and nectar from treated plants. In addition, some metabolites of imidacloprid are more toxic than the parent compound. So, the fate of imidacloprid and its metabolites in commodities to which honeybees get exposed needs to be overhauled.

OBJECTIVE

To validate QuEChERS method for estimation of imidacloprid and its metabolites in cotton flower, pollen, nectariferous tissue and honey using HPLC.

METHODS

The QuEChERS method was validated in terms of selectivity, linearity, LOD, LOQ, matrix match, accuracy, and precision. The estimation of residues was done by HPLC.

RESULTS

Recoveries of imidacloprid and its metabolites for cotton flowers, nectariferous tissue, pollen and honey samples were in the range of 80.42 to 99. 83%. LOQ for imidacloprid and its metabolites was 0.01 ug/g. Acceptable precision (RSD < 20%) was obtained.

CONCLUSIONS

The method allows simple and fast extraction of imidacloprid and its metabolites from cotton flower, pollen, nectariferous tissue and honey.

HIGHLIGHTS

An accurate, simple, and sensitive analytical method was validated for imidacloprid and its metabolites. The method was validated according to the SANTE/12682/2019 guidelines.

Protocol for sampling and analysis of food and agricultural produces consequent to a nuclear accident in India

Nuclear accidents, despite having an extremely low probability of occurrence, could cause uncontrolled release of radioactive elements (fission and activation products) into the environment, and may ultimately lead to contamination of food products. Such a scenario requires extraordinary measures for control of food, which might be contaminated to a level not suitable for human consumption. Agricultural products (which include grain crops, vegetable, fruits, dairy, meat, eggs and poultry) pass through a series of local, district and state level markets to finally reach consumers. An effective intervention at different stages of distribution by targeted sampling and analysis of suspected (contaminated) foodstuffs will substantially reduce the chances of contaminated food to reach the public. At the same time, it will also ensure food security of the people without imposing unreasonable restrictions in market flow. This can also help in getting the farmers adequately compensated. This paper presents a protocol for sampling and analysis suitable for India, considering the diversity with respect to climate, soil type, land use, crop pattern, population density, etc. The paper also provides an estimate of infrastructure requirement to carry out environmental monitoring following the emergency with respect to human resources and instruments. The paper proposes to use the national web portal for collection of data pertaining to crop pattern, land use and market flow. A web-based decision support system (Web-DSS) on a GIS platform, for sampling, analysis and display of data online would enhance the transparency of decision being taken and enable the administrators to effectively monitor the work flow, details of sample collection, analysis and effective use of human and other resources.

Sorption-desorption coefficients of uranium in contaminated soils collected around Fukushima Daiichi Nuclear Power Station

Various radionuclides including fission products and heavy nuclides were released into the environment during the Fukushima Daiichi Nuclear Power Station (FDNPS) accident. The dissolution followed by migration of deposited radionuclides of Cs, Sr and U on soils could take place to the local environment. Therefore, it is necessary to determine sorption-desorption coefficients of U in soil-water system around the FDNPS from a migration viewpoint. The determination of sorption coefficient K_d(S) as well as desorption coefficient K_d(D) for U has been carried out in the present study using a laboratory batch method. Stable U was used for sorption from simulated ground water onto contaminated soil samples collected from Okuma Town, Fukushima. Different soil parameters were measured to understand their effects on sorption and desorption processes. The obtained K_d(S) and K_d(D) values of U were compared with values of K_d(S) and K_d(D) of Cs and Sr and K_d(S)-U in known Fukushima accident contaminated soils reported in the literature for better understanding. It was observed that K_d(S)-U varied from 160 to 5100 L/kg, whereas K_d(D)-U ranged from 200 to 11000 L/kg. K_d(D) was higher than K_d(S) for U in these soils implying irreversibility of the sorption process. Pearson's correlation of K_d(S) values suggested that U sorption is affected by various soil parameters. However, desorption is decided by the nature of U species formed in sorption process and soil parameters like pH, presence of carbonates, Ca ions, clay minerals etc. to some extent. The comparison between K_d(S) and K_d(D) values for Cs, Sr and U revealed that unsorbed Sr could migrate farther than unsorbed Cs or U under the present experimental conditions. Both sorption and desorption studies are of great importance to understand migration of metal ions from contaminated sites to local uncontaminated areas.

Measurement of uranium isotope ratios in Fukushima-accident contaminated soil samples using multi collector inductively coupled plasma mass spectrometry

In the present study, ¹³⁷Cs and ²³⁸U activity concentrations, ²³⁴U/²³⁸U activity ratio, and ²³⁵U/²³⁸U isotope ratio were measured in fifteen soil samples collected from the exclusion zone around the Fukushima Daiichi Nuclear Power Station (FDNPS). The ¹³⁷Cs activity concentrations of Fukushima-accident contaminated soil samples ranged from 29.9 to 4780 kBq kg^-1 with a mean of 2007 kBq kg^-1. On the other hand, the ²³⁸U activity concentrations of these soil samples ranged from 5.2 to 22.4 Bq kg^-1 with a mean of 13.2 Bq kg^-1. The activity ratios of ²³⁴U/²³⁸U ranged from 0.973 to 1.023. The ²³⁵U/²³⁸U isotope ratios of these exclusion zone soil samples varied from 0.007246 to 0.007260, and they were similar to the natural terrestrial ratio confirming the natural origin. Using isotope dilution technique, the ²³⁵U/¹³⁷Cs activity ratio was theoretically estimated for highly ¹³⁷Cs contaminated soil samples from Fukushima exclusion zone ranged from 5.01 × 10^-8 - 6.16 × 10^-7 with a mean value of 2.51 × 10^-7.

Geochemical characterization of monazite sands based on rare earth elements, thorium and uranium from a natural high background radiation area in Tamil Nadu, India

The Kanyakumari coastal area in the southernmost part of Tamil Nadu, India is a well-known natural high background radiation area due to the abundance of monazite in beach placer deposits. In the present study, the concentrations of major oxides, rare earth elements (REEs), Th and U were measured to understand geochemical characteristics of these monazite sands. Based on the ambient dose rate, 23 locations covering an area of about 60 km along the coast were selected for sample collection. The concentrations of U and Th ranged from 1.1 to 737.8 μg g^-1 and 25.2-12250.6 μg g^-1, respectively. The Th/U ratio ranged from 2.2 to 61.6, which clearly indicated that Th was the dominant contributing radionuclide to the enhanced natural radioactivity in this coastal region. The chondrite-normalized REEs pattern of the placer deposits showed enrichment in light REEs and depletion in heavy REEs with a negative Eu anomaly that indicated the monazite sands were derived from granite, charnockite, and granitoid rocks from the Nagercoil and the Trivandrum Blocks of the Southern Granulite Terrain.

Embryonal tumors with multilayered rosettes: A tertiary care centre experience

BACKGROUND

Embryonal tumors with multilayered rosettes (ETMR) is an extremely rare and highly aggressive tumor. It includes three distinct entities i.e, embryonal tumor with abundant neuropil and true rosettes (ETANTR), ependymoblastoma (EBL) and medulloepithelioma (MEPL). Here, we present our institutional experience of seven ETMR cases treated over a period of five years.

MATERIALS AND METHODS

Patients' records from 2015 to 2019 were reviewed manually and electronically to retrieve the data. Clinicopathological and outcome details of ETMR cases were entered in a predesigned proforma.

RESULTS

A total of seven cases of ETMR were registered from 2015 to 2019 with a median age at presentation of four years (range 3-7 years). All patients underwent surgery. However, only three patients completed the planned adjuvant treatment, comprising of focal radiotherapy (RT) alone, craniospinal irradiation (CSI) alone and CSI followed by six cycles of chemotherapy in one patient each respectively. Two patients commenced CSI but deteriorated during RT and thereafter needed best supportive care. Two patients could not be started on any adjuvant treatment. Unfortunately, six patients succumbed to their disease within one year of their diagnosis. Only one patient who received both CSI and adjuvant chemotherapy is alive at 15 months of diagnosis.

CONCLUSION

ETMR is a rare and aggressive entity. Majority of the patients die within one year of the diagnosis despite multimodality treatment.

Can Increased Metabolic Status be a Grading Tool for Oral Squamous Cell Carcinoma? A Glucose Transporter 1 Immunoexpression Study

Background:

Glucose transporter-1 (GLUT-1) is a GLUT protein whose expression is upregulated in malignant cells where enhanced uptake of glucose is observed.

Aim:

The aim of this study is to evaluate the expression of GLUT-1 protein in oral squamous cell carcinoma (OSCC) tissue sections using immunohistochemistry and to describe the relationship between increased metabolic status and the grades of OSCC.

Materials and Methods:

This is cross-sectional study with 76 formalin-fixed paraffin-embedded tissue blocks of OSCC, obtained from the archives of the department. All the cases were scored using Bryne's grading system by three oral pathologists independently. The tissue sections were then stained using immunohistochemistry with anti-GLUT-1 rabbit monoclonal antibody.

Results:

Staining intensity and localization of positively stained slides were evaluated. Overall, a significant correlation between Bryne's histopathological grading system for OSCC and GLUT-1 immunohistochemical expression was observed. Thus, high GLUT-1 expressions are observed with increasing grades of OSCC.

Conclusion:

This study shows that a significant positive correlation exists between GLUT-1 immunoexpression and histological grading of OSCC. Thus, GLUT-1 expression can be used as a diagnostic adjunct and prognostic marker for OSCC patients.

MEASUREMENT OF URANIUM IN URINE, HAIR AND NAILS IN SUBJECTS OF NISKA BANJA TOWN, A HIGH NATURAL BACKGROUND RADIATION AREA OF SERBIA

Urine, hair and nail samples were collected from a population of both sex aged from 40 to 87 years in Niška Banja (227 km south of Belgrade, Serbia) with a high level of natural radioactivity (HLNRA). To assess and monitor the public exposure, urine samples for each subject (24 h period) were collected and concentration of uranium (U) was analysed using alpha-particle spectrometry. Human hair and nails considered as bio-indicators of the public exposure to radionuclides over a long period of months or even years and concentration of U was determined using inductively coupled plasma-mass spectrometry. The mean concentrations of U in urine, hair and nail were 123 ng/L, 17 ng/g and 8 ng/g, respectively. There was a large variation and may be due to geological origin.

URANIUM, THORIUM AND RARE EARTH ELEMENTS DISTRIBUTION IN FUKUSHIMA SOIL SAMPLES

Uranium, thorium and rare earth elements (REEs) in soil samples contaminated by Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident was determined using inductively coupled plasma-mass spectrometry (ICP-MS). This information provides knowledge about concentration levels of REEs in soil samples as a background data after FDNPP accident. Chondrite-normalised REEs pattern does not show enrichment in concentrations of REEs, which could be related to FDNPP accident. The high concentration of these elements at few sampling points may be due to soil formation process from granitic rocks.

NATURAL RADIOACTIVITY MEASUREMENT AND DOSE ASSESSMENT OF BEACH PLACER SANDS IN THE COASTAL REGION OF TAMIL NADU (INDIA)

A preliminary study was carried out to determine the radioactivity concentration of 232Th, 226Ra and 40K in beach placer sands from 13 locations along the coast line of Tamil Nadu state, India. The ambient dose rates varied from 9 to 467 nGy h-1. The activity concentrations of radionuclide 232Th, 226Ra and 40K ranged from 5.2 to 683 Bq kg-1, 13 to 198 Bq kg-1 and 107 to 421 Bq kg-1, respectively. The annual effective dose rate ranges from 27 to 620 μSv y-1 and was higher at seven beaches in comparison to the UNSCEAR annual worldwide average value.

Measurement of uranium distribution coefficient and 235U/238U ratio in soils affected by Fukushima dai-ichi nuclear power plant accident

Fukushima Daiichi Nuclear Power Plant (FDNPP) accident resulted radioactive contamination in soil due to deposition of mainly radiocesium as well as many long-lived radionuclides surrounding a large area around FDNPP. Depending upon environmental conditions, radionuclides in soil can be mobilized in aquatic systems. Therefore, the fate and transfer of these radionuclides in the soil water system is very important for radiation protection and dose assessment. In the present study, soil and water samples were collected from contaminated areas around FDNPP. Inductively coupled plasma mass spectrometry (ICP-MS) is used for total uranium concentration. Emphasis has been given on isotope ratio measurement of ²³⁵U/²³⁸U ratio using thermal ionization mass spectrometry (TIMS) that gives us the idea about its contamination during accident. For the migration behavior, its distribution coefficient (K_d) has been determined using laboratory batch method. Chemical characterization of soil with respect to different parameters has been carried out. The effect of these soil parameters on distribution coefficient of uranium has been studied in order to explain the radionuclide mobility in this particular area. The distribution coefficient values for uranium are found to vary from 30 to 36000 L/kg. A large variation in the distribution coefficient values shows the retention or mobility of uranium is highly dependent on soil characteristics in the particular area. This variation is explained with respect to soil pH, Fe, Mn, CaCO₃ and organic content. There is a very good correlation of uranium K_d obtained with Fe content. There is no enrichment of ²³⁵U has been noticed in the studied area.

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).

238Pu/(239+240)Pu activity ratio as an indicator of Pu originating from the FDNPP accident in the terrestrial environment of Fukushima Prefecture

The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident has caused significant radionuclide contamination. Pu isotopes at the level of GBq were released from the damaged reactors to terrestrial and marine ecosystems. In this work, 35 samples were collected at different locations of Fukushima. Samples consisted of three types, soil, forest litter and alluvial dust (road dust, sludges from drainage systems and below gutter pipe outflows). The obtained activity ratios of ²³⁸Pu/^(239+240)Pu ranged from 0.030 to 1.86. 14 of our samples contained trace amounts of Pu originating from the damaged reactors (2SM verification). Our study identified a few previously unknown "hot spots" of ²³⁸Pu/^(239+240)Pu activity ratio localized in an area between 15 and 30 km in the northwest direction from the FDNPP. Additionally, results obtained in this study combined with previously published data allowed us to prepare a map of spatial distribution of the Pu isotope fingerprints (²³⁸Pu/^(239+240)Pu) in Fukushima Prefecture.

Radiocesium and 40K distribution of river sediments and floodplain deposits in the Fukushima exclusion zone

In this study, radiocesium and ⁴⁰K analysis were accomplished for samples of riverbed sediments and floodplain deposits collected from five rivers in the vicinity (<20 km) of the damaged Fukushima Daiichi Nuclear Power Plant after seven years of the accident. Sediment particle size distribution and major oxide content were determined also for six selected samples to understand the retention and migration process of radiocesium in river environments. The radiocesium activity concentration varied from 103 ± 6 Bq·kg^-1 to 22,000 ± 500 Bq·kg^-1 in riverbed sediments and from 92 ± 5 Bq·kg^-1 to 117,000 ± 2000 Bq·kg^-1 in floodplain deposits. The ¹³⁴Cs/¹³⁷Cs ratio (decay corrected to 15 March 2011) was 1.02 in the both samples. Compared to monitoring results in 2011, it was proved that the radiocesium distribution pattern had been changed remarkably during seven years. The radiocesium was primarily attached to fine clay particles but its sorption on sand and coarse sand particles was also considerable. The sorption process of radiocesium was not affected by the presence of water and moreover, after seven years of the Fukushima accident, a significant radiocesium migration cannot be expected without particle migration. Consequently, radiocesium will remain for a long time in the river environments and its redistribution is mainly affected by the erosion process of the sediments. The average ⁴⁰K activity concentration of riverbed sediment and floodplain deposit samples was 640 ± 152 Bq·kg^-1 changing from 319 ± 18 Bq·kg^-1 to 916 ± 41 Bq·kg^-1. In the river estuary zones, significant activity concentration decrements were observed for both radionuclides. This suggests that seawater intrusion has a decreasing effect on both natural and artificial radionuclides via wash-out of particulate radiocesium and ⁴⁰K, and desorption of these radionuclides, but to reveal the detail of this process further investigations are required. The analysis of ⁴⁰K can help in a simple and easy way to reveal the mineral composition differences of sediment samples.

THE SCREENING INDOOR RADON AND PRELIMINARY STUDY OF INDOOR THORON CONCENTRATION LEVELS IN KUWAIT

Indoor measurements of radon and thoron in Kuwait were conducted during the years 2015 and 2016. In this study, 65 dwellings were selected for the long-term radon-thoron survey using passive nuclear track monitors. The monitors (at least one) were used at various locations in the dwellings for 83-306 days. Some measurements were also repeated at the same locations in different seasons. This current study is a preliminary thoron survey with relatively small sample size. The results showed that the range of thoron concentration was from below the lower limit of detection to 35 Bq m-3, whereas the range of radon concentration was within 10-202 Bq m-3. Furthermore, 22% of the radon results exceeded the WHO radon reference level of 100 Bq m-3. The analysis of variance showed a correlation between indoor radon concentration and the season. However, the thoron measurements were rather limited and the values were low. In addition, the relationship was investigated between radon and thoron concentrations involving the floor levels and the type of ventilation systems used.

Estimation of Salivary and Serum Lactate Dehydrogenase in Oral Submucous Fibrosis

AIM AND OBJECTIVES

The objective of the present study was to estimate the serum and salivary lactate dehydrogenase (LDH) levels in patients with oral submucous fibrosis (OSMF) and to study the association between serum and salivary LDH levels and mouth opening, frequency of habit, and duration of habit in patients with OSMF.

MATERIALS AND METHODS

Participants were divided into two groups: Group I - case group diagnosed with OSMF and Group II - the control group. Unstimulated whole saliva was collected from all the participants. The International Federation of Clinical Chemistry method was carried out with the help of LDH (P-L) kit (Crest Biosystems, Goa). Collection of blood sample was done under aseptic precautions and processed for LDH. The data were analyzed using SPSS software 2010 (version 19, IBM, Armonk, NY, USA). Descriptive statistics including mean, range, standard deviation, and percentage were used along with unpaired t-test and Pearson's correlation test.

RESULTS

All the participants were male and were in the age range of 18-60 years, with a mean age of 28.63 ± 10.39 years. The mean salivary LDH levels in patients with OSMF were 1057.30 ± 640.12 μg/dl and in the control group were 668.25 ± 498.45 μg/dl. The mean serum LDH level in patients with OSMF was 408.35 ± 158.35 μg/dl as compared to the control group was 313.05 ± 82.69 μg/dl. The Pearson's correlation coefficient between serum LDH and frequency of habit, duration of habit, and mouth opening was found to be 0.55, 0.53, and 0.69, respectively. The Pearson's correlation coefficient between salivary LDH and frequency of habit, duration of habit, and mouth opening was found to be 0.33, 0.04, and 0.13, respectively. The Pearson's correlation coefficient between salivary LDH and serum LDH was found to be -0.18.

CONCLUSIONS

There was a significant increase in the serum and salivary LDH in OSMF patients as compared to controls; the salivary LDH did not seem to correlate with frequency of the habit, duration of the habit, or mouth opening of OSMF patients. However, serum LDH was found to correlate directly with frequency of the habit and mouth opening in OSMF patients. Hence, based on the results of the present study, it can be hypothesized that serum LDH is a better biological marker than salivary LDH in the evaluation of OSMF.

Multilocation field trials for risk assessment of a combination fungicide Fluopicolide + Propamocarb in tomato

Dissipation kinetics of two systemic fungicides, namely fluopicolide and propamocarb used as a combination formulation (Infinito 68.75 SC), were studied on tomato at four different locations by the All India Network Project on Pesticide Residues to recommend their pre-harvest interval (PHI) and to propose the maximum residue limits (MRL) for the two fungicides based on chronic hazard exposure assessment. The combination fungicide was sprayed thrice at the recommended dosage of 93.75 g a.i./ha fluopicolide and 937.50 g a.i./ha propamocarb as well as at double the recommended dosage of 187.50 g a.i./ha fluopicolide and 1875.0 g a.i./ha propamocarb on tomato crops and the residues were monitored periodically by GC-MS. The fungicides dissipated to below the limit of quantification (LOQ) within 10 to 15 days, with a half-life of 2-4 days for fluopicolide and 1-2 days for propamocarb. Taking into consideration the MRLs of codex and calculations made using the method of MRL fixation of the Food Safety and Standard Authority of India (FSSAI) as well as the Organization for Economic Co-operation and Development (OECD) calculator, MRL of 5 mg/kg is proposed for fluopicolide and 15 mg/kg for propamocarb, following critical exposure of the commodity considering PHI of 1 day.

NATURAL RADIOACTIVITY LEVEL AND ELEMENTAL COMPOSITION OF SOIL SAMPLES FROM A HIGH BACKGROUND RADIATION AREA ON EASTERN COAST OF INDIA (ODISHA)

A comprehensive study was carried out to determine the radioactivity concentration of soil samples from different sites of a high background radiation area in the eastern coast of India, Odisha state. The dose rate measured in situ varied from 0.25 to 1.2 µSv h^-1 The gamma spectrometry measurements indicated Th series elements as the main contributors to the enhanced level of radiation and allowed the authors to find the mean level of the activity concentration (±SD) for ²²⁶Ra, ²²⁸Th and ⁴⁰K as 130±97, 1110±890 and 360±140 Bq kg^-1, respectively. Human exposure from radionuclides occurring outdoor was estimated based on the effective dose rate, which ranged from 0.14±0.02 to 2.15±0.26 mSv and was higher than the UNSCEAR annual worldwide average value 0.07 mSv. Additionally, X-ray fluorescence analysis provided information about the content of major elements in samples and indicated the significant amount of Ti (7.4±4.9 %) in soils.

Oceanic oxygenation events in the anoxic Ediacaran ocean

The ocean-atmosphere system is typically envisioned to have gone through a unidirectional oxygenation with significant oxygen increases in the earliest (ca. 635 Ma), middle (ca. 580 Ma), or late (ca. 560 Ma) Ediacaran Period. However, temporally discontinuous geochemical data and the patchy metazoan fossil record have been inadequate to chart the details of Ediacaran ocean oxygenation, raising fundamental debates about the timing of ocean oxygenation, its purported unidirectional rise, and its causal relationship, if any, with the evolution of early animal life. To better understand the Ediacaran ocean redox evolution, we have conducted a multi-proxy paleoredox study of a relatively continuous, deep-water section in South China that was paleogeographically connected with the open ocean. Iron speciation and pyrite morphology indicate locally euxinic (anoxic and sulfidic) environments throughout the Ediacaran in this section. In the same rocks, redox sensitive element enrichments and sulfur isotope data provide evidence for multiple oceanic oxygenation events (OOEs) in a predominantly anoxic global Ediacaran-early Cambrian ocean. This dynamic redox landscape contrasts with a recent view of a redox-static Ediacaran ocean without significant change in oxygen content. The duration of the Ediacaran OOEs may be comparable to those of the oceanic anoxic events (OAEs) in otherwise well-oxygenated Phanerozoic oceans. Anoxic events caused mass extinctions followed by fast recovery in biologically diversified Phanerozoic oceans. In contrast, oxygenation events in otherwise ecologically monotonous anoxic Ediacaran-early Cambrian oceans may have stimulated biotic innovations followed by prolonged evolutionary stasis.

Estimation and risk assessment of flubendiamide on fodder berseem clover (Trifolium alexandrinum L.) by QuEChERS methodology and LC-MS/MS

The residues of flubendiamide from berseem were extracted and cleaned up by the QuEChERS approach and analysed by liquid chromatography/mass spectrometry (LC-MS/MS). The dissipation studies on berseem were carried out by application of flubendiamide at five different dosages i.e. 24, 36, 48, 72 and 96 g a.i. ha(-1). The residues reached below determination limit (BDL) of 0.01 mg kg(-1) in 7, 10, 10, 15 and 15 days for 24, 36, 48, 72 and 96 g.a.i. ha(-1)dosages, respectively. Half-life (t1/2) of flubendiamide on berseem was observed to be 1.08, 1.88, 1.94, 2.26 and 2.27 days, respectively, at 24, 36, 48, 72 and 96 g a.i. ha(-1). Theoretical maximum residue contributions (TMRC) values reached below the maximum permissible limit (MPI) for 3, 5 and 7 days in treatments at 24, 36 and 48 g.a.i. ha(-1), respectively, whereas in case of higher dose treatments i.e. 72 and 96 g a.i. ha(-1), the residues of flubendiamide reached below MPI after 10 days of treatment. These data could provide guidance for the proper and safe use of this pesticide on berseem in India.

Uptake of uranium by aquatic plants growing in fresh water ecosystem around uranium mill tailings pond at Jaduguda, India

Concentration of uranium was determined in aquatic plants and substrate (sediment or water) of fresh water ecosystem on and around uranium mill tailings pond at Jaduguda, India. Aquatic plant/substrate concentration ratios (CRs) of uranium were estimated for different sites on and around the uranium mill tailings disposal area. These sites include upstream and downstream side of surface water sources carrying the treated tailings effluent, a small pond inside tailings disposal area and residual water of this area. Three types of plant groups were investigated namely algae (filamentous and non-filamentous), other free floating & water submerged and sediment rooted plants. Wide variability in concentration ratio was observed for different groups of plants studied. The filamentous algae uranium concentration was significantly correlated with that of water (r=0.86, p<0.003). For sediment rooted plants significant correlation was found between uranium concentration in plant and the substrate (r=0.88, p<0.001). Both for other free floating species and sediment rooted plants, uranium concentration was significantly correlated with Mn, Fe, and Ni concentration of plants (p<0.01). Filamentous algae, Jussiaea and Pistia owing to their high bioproductivity, biomass, uranium accumulation and concentration ratio can be useful for prospecting phytoremediation of stream carrying treated or untreated uranium mill tailings effluent.

Measurement of 90Sr in contaminated Fukushima soils using liquid scintillation counter

A method based on liquid scintillation counting system has been developed for the measurement of (90)Sr in Fukushima soil samples due to contamination of (134)Cs and (137)Cs. Three soil samples were collected within 30 km radius from the Fukushima Daiichi Nuclear Power Plant (FDNPP). Activity concentration of (134)Cs and (137)Cs were measured using a gamma spectroscopy system with high-purity germanium detector. (90)Sr contamination is little elevated but comparable with the background contamination level that originated from atmospheric nuclear weapon tests, whereas radiocesium contamination has increased significantly. Activity concentration of (90)Sr in the soil samples varied in the range of 10.4±0.6-22.0±1.2 Bq kg(-1). Activity concentrations of (134)Cs and (137)Cs in the soil samples were in the range of 28.2±0.2-56.3±0.2 kBq kg(-1) and 35.2±0.1-70.2±0.2 kBq kg(-1), respectively (reference date for decay correction is 1 December 2011).

Estimation of radon emanation coefficient for representative soils in Okinawa, Japan

Radon ((222)Rn) emanation coefficients for the representative soils distributed in Okinawa Island, Japan, have been estimated empirically. Arithmetic means of the emanation coefficients for dry and moist conditions were calculated to be 0.19 and 0.29, respectively. In Okinawa, the soils are traditionally classified into three types, namely the dark red soils, the residual regosols and the red and yellow soils. The dark red soils have relatively high coefficients. The residual regosols and the red and yellow soils have relatively low coefficients. To investigate the variable factor of the emanation coefficients, analyses of radioactive elements and physical properties have also been performed on the soils. For the dark red soils, the contents of the fine particle and the (226)Ra are relatively higher than those for the other soils. Based on these results, it is suggested that the variation in the radon emanation coefficient is mainly regulated by the (226)Ra concentration, the particle sizes and the water contents of the soils.

Comparative dosimetry for radon and thoron in high background radiation areas in China

The present study focuses on internal exposure caused by the inhalation of radon and thoron progenies because the internal exposures have not yet been clarified. For their dose assessment, radon, thoron and thoron progeny concentrations were measured by passive monitors over a long period (for 6 months). Consequently, radon, thoron and equilibrium equivalent thoron concentrations were given as 124 ± 78, 1247 ± 1189 and 7.8 ± 9.1 Bq m(-3), respectively. Annual effective doses are estimated to be 3.1 ± 2.0 mSv for radon and 2.2 ± 2.5 mSv for thoron. Total dose are estimated to be 5.3 ± 3.5 mSv a(-1). The present study has revealed that the radon dose was comparable with the thoron dose, and the total dose was ∼2 times higher than the worldwide average.

Variability of radiocaesium inventory in Fukushima soil cores from one site measured at different times

The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident has resulted in the deposition of radioactive contamination of soils mainly by (134)Cs and (137)Cs. The contaminated areas are of a great concern since external radiation may lead to significant long-term doses to humans and animals. External dose rate above ground will decrease with physical decay of the radionuclides and as they migrate deeper into the soil with time. In the present study, depth profiles of Cs radioisotopes have been studied at different times over a period of 1 y. Radiocaesium inventories for (134)Cs and (137)Cs down to a depth of 10 cm at the four measurement times varied from 2.09 to 4.14 MBq m(-2) with coefficient of variation (CV): 27.4 %, n = 4 and from 2.13 to 4.23 MBq m(-2) with CV: 27.3 %, n = 4, respectively. The activity ratio for (134)Cs/(137)Cs decreased from 0.62 to 0.46 during 1 y of measurement i.e. July 2012 to June 2013. However, the ratio with decay correction (15 March 2011) was found to be constant ∼1, indicating contamination from FDNPP origin. In order to understand the radiocaesium distribution in soil profile, physico-chemical characterisation of soil has been carried out.

Comparative study of various techniques for environmental radon, thoron and progeny measurements

Long-term average concentrations of radon, thoron and progeny were measured in normal and high background radiation areas in India using different techniques. Radon, thoron and progeny concentrations were measured using Raduet, Pin-Hole dosimeter, deposition-based CR-39 and deposition-based direct radon/thoron progeny sensor (DRPS/DTPS) detector system. All these techniques were used at a same time inside an individual dwelling. Radon concentration was recorded higher than thoron concentration in Garhwal Homes (NBRA) while thoron concentration was found relatively higher in the houses of Chhatarpur area (HBRA) in Odisha, India. The values measured with the CR-39 detector-based technique were found comparable with the values measured with the LR-115 detector-based technique. The comparisons of results using various techniques and their usefulness in radiation measurements are discussed in detail.

Distribution of uranium, thorium and some stable trace and toxic elements in human hair and nails in Niška Banja Town, a high natural background radiation area of Serbia (Balkan Region, South-East Europe)

Human hair and nails can be considered as bio-indicators of the public exposure to certain natural radionuclides and other toxic metals over a long period of months or even years. The level of elements in hair and nails usually reflect their levels in other tissues of body. Niška Banja, a spa town located in southern Serbia, with locally high natural background radiation was selected for the study. To assess public exposure to the trace elements, hair and nail samples were collected and analyzed. The concentrations of uranium, thorium and some trace and toxic elements (Mn, Ni, Cu, Sr, Cd, and Cs) were determined using inductively coupled plasma mass spectrometry (ICP-MS). U and Th concentrations in hair varied from 0.0002 to 0.0771 μg/g and from 0.0002 to 0.0276 μg/g, respectively. The concentrations in nails varied from 0.0025 to 0.0447 μg/g and from 0.0023 to 0.0564 μg/g for U and Th, respectively. We found significant correlations between some elements in hair and nails. Also indications of spatial clustering of high values could be found. However, this phenomenon as well as the large variations in concentrations of heavy metals in hair and nail could not be explained. As hypotheses, we propose possible exposure pathways which may explain the findings, but the current data does not allow testing them.

Risk assessment of mixture formulation of spirotetramat and imidacloprid in chilli fruits

Persistence and risk assessment of spirotetramat and imidacloprid in chilli fruits were studied following three applications of a mixture formulation of spirotetramat (12%) and imidacloprid (12%) at 1000 and 2000 mL ha(-1). Residues of spirotetramat and imidacloprid in chilli were estimated by high-performance liquid chromatograph (HPLC). Residues of spirotetramat and imidacloprid dissipated to more than 65% after 3 days at both the dosages. Residues of spirotetramat on chilli fruits were found to be below its limit of quantification (LOQ) of 0.03 mg kg(-1) after 5 and 7 days for recommended and double the recommended dosages, respectively. Similarly, imidacloprid residues were found to be below its LOQ of 0.01 mg kg(-1) at 7 and 10 days, respectively. Half-life periods for spirotetramat were found to be 1.91 and 1.30 days, whereas, for imidacloprid, these values were observed to be 1.41 and 1.65 days at recommended and double the recommended dosages, respectively. Red chilli samples collected after 20 days of the last application did not show the presence of spirotetramat and imidacloprid at their respective determination limit. As the theoretical maximum residue contributions on chilli fruits are found to be less than the maximum permissible intake values on initial deposits, a waiting period of 1 day may follow to reduce risk before consumption at the recommended dose.

Degradation pattern and risk assessment of chlorantraniliprole on berseem (Trifolium alexandrinum L.) using high performance liquid chromatography

The persistence pattern of chlorantraniliprole on berseem leaves and its risk assessment for the safety of cattle were studied. QuEChERS method was used for the extraction and cleanup of samples and the residues of chlorantraniliprole were estimated using high performance liquid chromatography (HPLC) and confirmed by Liquid Chromatograph-Mass Spectrometer (LCMS-MS). The dissipation studies on berseem were carried out by application of chlorantraniliprole at five different dosages i.e. 11.6, 17.1, 23.1, 34.7 and 46.2 g a.i. ha(-1). Average initial deposits of chlorantraniliprole were found to be 0.47, 0.61, 0.78, 1.15 and 1.31 mg kg(-1), respectively. The residues reached below determination limit (BDL) of 0.01 mg kg(-1) in 5, 7, 7, 10 and 10 days for 11.6, 17.1, 23.1, 34.7 and 46.2 g a.i. ha(-1) dosages, respectively. Half-life (t1/2) of chlorantraniliprole on berseem was observed to be 0.93, 1.14, 1.06, 1.00 and 1.33 days, respectively, at 11.6, 17.1, 23.1, 34.7 and 46.2 g a.i. ha(-1). It was found that the theoretical maximum residue contributions (TMRC) values reached below maximum permissible intake (MPI) on 0 day in berseem samples treated with chlorantraniliprole. These studies, therefore suggest that the use of chlorantraniliprole formulation at different dosages does not seem to pose any hazards to the consumers and a waiting period of one day is suggested to reduce the risk before consumption of berseem leaves. These data could provide guidance for the proper and safe use of this pesticide on berseem in India.

Risk assessment of β-cyfluthrin and imidacloprid in chickpea pods and leaves

Dissipation of β-cyfluthrin and imidacloprid in chickpea pods and leaves was measured following three applications of Solomon 300 OD (β-cyfluthrin 9 percent +imidacloprid 21 percent) at 200 and 400mLha(-1). Residues of β-cyfluthrin on chickpea pods and leaves were found to be below its limit of quantification (LOQ) of 0.01mgkg(-1) after 7 days at both the dosages. Similarly, imidacloprid residues were found to be below its LOQ of 0.01mgkg(-1) at 10 days. Half-life periods on chickpea pods and leaves for β-cyfluthrin were found to be 1.06 and 0.58 days, whereas for imidacloprid these values were observed to be 2.07 and 1.75 days at recommended dose. As the theoretical maximum residue contributions on chickpea pods and leaves are found to be less than the maximum permissible intake values even on 0 day, therefore consumer health risks are minimal at both the dosages on chickpea.

Estimation of quizalofop ethyl residues in black gram (Vigna mungo L.) by gas liquid chromatography

Quizalofop ethyl, a phenoxy propionate herbicide is used for post emergence control of annual and perennial grass weeds in broad-leaved crops in India. The experiments were designed to study the harvest time residues of quizalofop ethyl in black gram for two seasons. At harvest time, the residues of quizalofop ethyl on black gram seed, foliage and soil were found to be below the determination limit of 0.01 mg kg(-1) following a single application of the herbicide at 50 and 100 g a.i. ha(-1) for both the periods. Application of the herbicide is quite safe from a consumer and environmental point of view.

Distribution of norm and 137Cs in soils of the Visakhapatnam region, Eastern India, and associated radiation dose

The specific activity of naturally occurring radioactive materials and (137)Cs in surface soils around the new Bhabha Atomic Research Centre site at Visakhapatnam region, Eastern India, has been determined using high-resolution gamma-ray spectrometry as part of a baseline radiological survey. Radiation hazard for the samples was assessed by radium equivalent activity (Raeq) and absorbed gamma dose rate (D). The mean absorbed gamma dose rate was found to be 104.9 nGy h(-1). The average annual effective dose equivalent was found to be 0.13 mSv y(-1).

Plasmodium vivax induced myocarditis: a rare case report

Malaria is one of the commonest parasitic disease in the tropics since ages. However the plasmodium still continues to give surprises to all of us. In the similar context we report a case of Plasmodium vivax induced myocarditis in a 20 year old male and review the literature related to this rare entitiy.

Persistence of thiacloprid residues on brinjal (Solanum melongena L.)

Thiacloprid, a neonicotinoid insecticide with novel mode of action, is found to be effective against several lepidopteran as well as hemipteran pests. The present studies were carried out to observe the persistence pattern of thiacloprid on brinjal and to suggest suitable waiting period for the safety of consumers. Persistence of thiacloprid in brinjal was studied following three applications of thiacloprid (Alanto 240 SC) at 180 and 360 g a.i. ha(-1) at 7 days interval. Residues of thiacloprid in brinjal were estimated by high-performance liquid chromatography and were confirmed by liquid chromatography-mass spectrometry. The average initial deposits of thiacloprid were observed to be 0.48 and 1.05 mg kg(-1) on the brinjal fruit following third application of thiacloprid at recommended and double the recommended dosages, respectively. Half-life periods for thiacloprid were found to be 0.47 and 0.50 days at single and double the application rates, respectively. Residues of thiacloprid declined below its limit of quantification of 0.05 mg kg(-1) after 3 and 5 days, respectively, at recommended and double the recommended application rates. Therefore, the use of thiacloprid does not seem to pose any risk hazard and a waiting period of 1 day is suggested for safe consumption of brinjal fruits.

Distribution of radionuclides in surface soils, Singhbhum Shear Zone, India and associated dose

Gamma emitters were estimated in surface soils from a mineralized zone in Eastern India using high purity Germanium detector-based high resolution gamma spectrometry system. Activities of (238)U, (226)Ra, (232)Th, (235)U, (227)Th, (234 m)Pa, (210)Pb, (40)K, and (137)Cs were 79 ± 50, 81 ± 53, 65 ± 23, 4 ± 2, 5 ± 4, 92 ± 50, 97 ± 45, 517 ± 201, and 4 ± 2 Bq/kg, respectively. Most radionuclides were observed to follow log-normal distribution. The correlation between physicochemical properties of the samples, like pH, organic matter content, particle size, and moisture content were also studied. Activity ratios of (226)Ra/(238)U, (210)Pb/(226)Ra, and (227)Th/(235)U indicated deviation from secular equilibrium in some samples. The associated annual effective dose ranged from 0.07 to 0.24 mSv and the mean was calculated to be 0.12 ± 0.04 mSv for this region, indicating it to be one of normal natural background radiation.

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

Uranium is a heavy metal that is not only radiologically harmful but also a well-known nephrotoxic element. In this study, occurrence of uranium in drinking water samples from locations near the uranium mining site at Jaduguda, India, was studied by Laser-induced fluorimetry. Uranium concentrations range from 0.03 ± 0.01 to 11.6 ± 1.3 µg l(-l), being well within the US Environmental Protection Agency drinking water limit of 30 μg l(-1). The ingestion dose due to the presence of uranium in drinking water for various age groups varies from 0.03 to 28.3 μSv y(-1). The excess lifetime cancer risk varies from 4.3×10(-8) to 1.7×10(-5) with an average value of 4.8×10(-6), much less than the acceptable excess lifetime cancer risk of 10(-3) for radiological risk. The chemical risk (hazard quotient) has an average value of 0.15 indicating that the water is safe for drinking.

Uptake of 210Po by aquatic plants of a fresh water ecosystem around the uranium mill tailings management facility of Jaduguda, India

PURPOSE

The present study was designed to investigate the uptake of Polonium-210 ((210)Po) by aquatic plants growing in a fresh water ecosystem around the tailings management facility of the uranium industry of Jaduguda, India. Evaluation of the activity concentration of (210)Po in aquatic plants, the concentration ratio of (210)Po from substrate to plants and the relationship of (210)Po with other stable elements were major objectives of the investigation.

MATERIALS AND METHODS

Based on the habitat, three types of plant were collected and analyzed for (210)Po activity estimation. Along with aquatic plants, effluent, surface water and bottom sediment were also collected and analyzed for (210)Po activity content. From the acid solution (210)Po was electrodeposited on brightly polished silver discs and counted for alpha activity in an alpha counter.

RESULTS

The highest (210)Po activity concentration (4884 Bq kg(-1) fresh weight) was found in filamentous algae from residual water of the tailings pond. For sediment-rooted plants, a significant positive correlation (r = 0.91, p < 0.0001) was observed between plant and sediment activity concentration of (210)Po.

CONCLUSIONS

For all of the three different groups of plants studied, highly significant correlations were observed between activity concentration of (210)Po and Cu with the significance level variation between 0.00-0.05 (both for linear and log transformed data).

Ingestion dose from 238U, 232Th, 226Ra, 40K and 137Cs in cereals, pulses and drinking water to adult population in a high background radiation area, Odisha, India

A natural high background radiation area is located in Chhatrapur, Odisha in the eastern part of India. The inhabitants of this area are exposed to external radiation levels higher than the global average background values, due to the presence of uranium, thorium and its decay products in the monazite sands bearing placer deposits in its beaches. The concentrations of (232)Th, (238)U, (226)Ra, (40)K and (137)Cs were determined in cereals (rice and wheat), pulses and drinking water consumed by the population residing around this region and the corresponding annual ingestion dose was calculated. The annual ingestion doses from cereals, pulses and drinking water varied in the range of 109.4-936.8, 10.2-307.5 and 0.5-2.8 µSv y(-1), respectively. The estimated total annual average effective dose due to the ingestion of these radionuclides in cereals, pulses and drinking water was 530 µSv y(-1). The ingestion dose from cereals was the highest mainly due to a high consumption rate. The highest contribution of dose was found to be from (226)Ra for cereals and drinking water and (40)K was the major dose contributor from the intake of pulses. The contribution of man-made radionuclide (137)Cs to the total dose was found to be minimum. (226)Ra was found to be the largest contributor to ingestion dose from all sources.

Residual behavior of quizalofop ethyl on onion (Allium cepa L.)

Quizalofop ethyl, a phenoxy propionate herbicide, is used for postemergence control of annual and perennial grass weeds in broad-leaved crops in India. The experiments were designed to study the dissipation kinetics of quizalofop ethyl on onion for two seasons. A simple, rapid, and sensitive method for estimation of quizalofop ethyl residues in onion and soil was developed and validated. The recoveries of quizalofop ethyl residues from onion and soil at different spiking level range from 84.81 to 92.68 %. The limit of quantification of this method was found to be 0.01 μg g(-1). The risk assessment through consumption of the onion in comparison to its acceptable daily intake which is an important parameter for the safety of the consumer was also evaluated. Standardized methodology supported by recovery studies was adopted to estimate residues of quizalofop ethyl on onion and soil. The average initial deposits of quizalofop ethyl on onion were observed to be 0.25 and 0.33 mg kg(-1), following single application of the herbicide at 50 g active ingredient (a.i.) ha(-1) during 2009 and 2010, respectively. The half-life values (T (1/2)) of quizalofop ethyl on onion crop were worked out to be 0.85 and 0.79 days, respectively, during 2009 and 2010. At harvest time, the residues of quizalofop ethyl on onion and soil were found to be below the determination limit of 0.01 mg kg(-1) following single application of the herbicide at 50 and 100 g a.i. ha(-1) for both the periods.

Formulation, in vitro drug release study and anticancer activity of 5-fluorouracil loaded gellan gum microbeads

5-Fluorouracil loaded calcium-zinc-gellan and calcium-zinc-gellan-ethyl cellulose microbeads were successfully prepared by simple ionotropic gelation and oil in water ionotropic gelation technique, respectively. Prepared microbeads were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and evaluated for particle size, drug content, encapsulation efficiency, drug release and cell cytotoxicity study. Microbeads formed were spherical with rough surface. As concentration of gellan and ethyl cellulose has increased encapsulation efficiency, particle size and sustained drug release effect also increased. The release of 5-fluorouracil from microbeads has followed Hixson Crowell model suggesting the mechanism of drug release as dissolution controlled. Cytotoxicity analysis on HT-29 human colon cancer cell lines indicated that 5-FU loaded gellan gum/gellan in combination with ethyl cellulose microbeads leads to sustained releases of drug and thus delayed apoptosis over a long period of time. The formulation with drug:gellan:ethyl cellulose ratio 2.5:7.5:1 was found to be more effectual in terms of sustained drug release activity in addition to anti-cancer activity.