RESUMO
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.
Assuntos
Benzamidas/análise , Carbamatos/análise , Fungicidas Industriais/análise , Resíduos de Praguicidas/análise , Solanum lycopersicum/química , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Índia , Limite de Detecção , Medição de RiscoRESUMO
A single trait linear mixed random regression test-day model was applied for the first time for analyzing the first lactation monthly test-day milk yield records in Karan Fries cattle. The test-day milk yield data was modeled using a random regression model (RRM) considering different order of Legendre polynomial for the additive genetic effect (4th order) and the permanent environmental effect (5th order). Data pertaining to 1,583 lactation records spread over a period of 30 years were recorded and analyzed in the study. The variance component, heritability and genetic correlations among test-day milk yields were estimated using RRM. RRM heritability estimates of test-day milk yield varied from 0.11 to 0.22 in different test-day records. The estimates of genetic correlations between different test-day milk yields ranged 0.01 (test-day 1 [TD-1] and TD-11) to 0.99 (TD-4 and TD-5). The magnitudes of genetic correlations between test-day milk yields decreased as the interval between test-days increased and adjacent test-day had higher correlations. Additive genetic and permanent environment variances were higher for test-day milk yields at both ends of lactation. The residual variance was observed to be lower than the permanent environment variance for all the test-day milk yields.
RESUMO
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.
Assuntos
Compostos Aza/análise , Capsicum/química , Imidazóis/análise , Inseticidas/análise , Nitrocompostos/análise , Compostos de Espiro/análise , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Frutas/química , Meia-Vida , Neonicotinoides , Medição de RiscoRESUMO
AIMS: Local failure remains the major concern in grade 4 glioma or glioblastoma (GBM). Pilot studies have shown a radiotherapy (RT) dose-response relationship in GBM. Here we present our preliminary data of RT dose escalation using 68Ga-Pentixafor PET scan. High 68Ga-pentixafor uptake in glioma cells helps in sharp demarcation between tumour and normal brain. MATERIALS AND METHODS: This phase II prospective study was conducted from 2018 to 2020. Thirty, biopsy-proven cases of grade 4 glioma were included. All patients underwent post-operative MRI of the brain and 68Ga-Pentixafor PET scan. RT was planned in 2-phases. Phase-1 GTV (GTV1) comprised of T2/flair abnormality, PET-avid disease and post-op cavity. A margin of 2cm was given to GTV-1 to create phase-1 CTV (CTV1), which was further expanded to 0.5cm to generate phase-1 PTV (PTV1). A radiation dose of 46Gy/23fr was prescribed to PTV-1. Phase-2 GTV (GTV2) consisted of CT/MRI contrast-enhancing lesion, PET avid disease and post-op cavity. A margin of 0.5 cm was given to GTV2 to create phase-2 CTV (CTV2) which was expanded to 0.5 cm to create phase-2 PTV (PTV2). RT dose of 14 Gy/7 fr was prescribed to PTV2. PET avid disease was delineated as GTV PET and a margin of 3mm was given to generate PTV-PET which received escalated RT dose of 21 Gy/7fr by simultaneous integrated boost (SIB) in phase 2 (Total dose to PTV PET = 67 Gy/30 fr). All patients received concurrent and adjuvant temozolomide. The data was prospectively maintained in Microsoft Excel sheet. SPSS v 23 was used for statistical analysis. The primary endpoints were estimation of the overall survival (OS) and progression-free survival (PFS), and secondary endpoint was to measure the incidence of radiation necrosis. Categorical variables were reported as frequency and percentage and quantitative variables were reported as median and range. RESULTS: Data from thirty patients were analysed. A median OS of 23 months was observed with estimated 1, 2 and 3 years OS of 90%, 40% and 17.8% respectively. A significant association of OS was seen with the extent of surgery (p = 0.04) and kernofsky performance status (p = 0.007). No patient developed significant radiation necrosis. CONCLUSIONS: The index study did not show any survival benefit from dose escalation RT. However, all of the patients tolerated the treatment well and none of them developed radiation necrosis. Considering the small sample size as a limitation of the index study, the role of 68Ga-pentixafor PET scan for radiation dose escalation should be further explored. CLINICAL TRIAL NUMBER: CTRI/2019/05/019146.
Assuntos
Neoplasias Encefálicas , Glioma , Tomografia por Emissão de Pósitrons , Humanos , Estudos Prospectivos , Masculino , Pessoa de Meia-Idade , Feminino , Glioma/radioterapia , Glioma/diagnóstico por imagem , Glioma/patologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Adulto , Tomografia por Emissão de Pósitrons/métodos , Idoso , Dosagem Radioterapêutica , Radioisótopos de Gálio , Gradação de TumoresRESUMO
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.
Assuntos
Radiação de Fundo , Doses de Radiação , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Solo/química , Índia , Monitoramento de RadiaçãoRESUMO
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.
Assuntos
Herbicidas/análise , Cebolas/química , Resíduos de Praguicidas/análise , Propionatos/análise , Quinoxalinas/análise , Monitoramento Ambiental , Meia-Vida , Herbicidas/química , Índia , Resíduos de Praguicidas/química , Propionatos/química , Quinoxalinas/química , Solo/química , Poluentes do Solo/análiseRESUMO
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.
Assuntos
Antimetabólitos Antineoplásicos/química , Portadores de Fármacos , Fluoruracila/química , Polissacarídeos Bacterianos/química , Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cloreto de Cálcio/química , Sobrevivência Celular/efeitos dos fármacos , Celulose/análogos & derivados , Celulose/química , Química Farmacêutica , Neoplasias do Colo/patologia , Preparações de Ação Retardada , Composição de Medicamentos , Fluoruracila/farmacologia , Células HT29 , Humanos , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Tecnologia Farmacêutica/métodos , Sulfato de Zinco/químicaRESUMO
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.
Assuntos
Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Espectrometria gama/métodos , Egito , Tório/análise , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Rádio (Elemento)/análiseRESUMO
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.
Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Poluentes Radioativos do Solo/análise , Solo , Índia , Dosímetros de Radiação , Radiação de Fundo , Doses de RadiaçãoRESUMO
Spherical agglomerates of pioglitazone hydrochloride were prepared by the emulsion solvent diffusion method with additives (polyethylene glycol 6000, polyvinyl pyrrolidone, beta cyclodextrin, eudragit RS100, low acyl gellan gum and xanthan gum) using methanol, chloroform and water as a good solvent, bridging liquid and poor solvent respectively. Prepared agglomerates were evaluated for compressibility, solubility, dissolution rate and bioavailability, and characterized by SEM, XRPD, DSC and FTIR spectroscopy. Particle size, flowability, compactibility, packability, solubility, dissolution rate and bioavailability of plain agglomerates and agglomerates with additives (except with polyvinyl pyrrolidone) were advantageously improved compared with raw crystalline pioglitazone hydrochloride. These improved properties for direct compression were due to their large-spherical shape and enhanced fragmentation during compaction, together with increased tensile strength and reduced elastic recovery of the compacts. XRPD and DSC studies indicated polymorphic transition of pioglitazone hydrochloride from form II to I during recrystallization but this was not associated with any chemical transition, as indicated by FTIR spectra, well supported by stability studies. Thus spherical crystallization by the emulsion solvent diffusion method with selected additives is a satisfactory method for direct tableting of pioglitazone hydrochloride giving improved bioavailability.
Assuntos
Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Tiazolidinedionas/administração & dosagem , Tiazolidinedionas/farmacocinética , Animais , Disponibilidade Biológica , Calibragem , Varredura Diferencial de Calorimetria , Cromatografia em Camada Fina , Cristalização , Difusão , Composição de Medicamentos , Estabilidade de Medicamentos , Emulsões , Hipoglicemiantes/química , Masculino , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Pioglitazona , Ratos , Ratos Wistar , Solubilidade , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Tiazolidinedionas/química , Difração de Raios XRESUMO
Dissipation of ß-cyfluthrin and imidacloprid in okra was studied following three applications of a combination formulation of Solomon 300 OD (ß-cyfluthrin 9 % + imidacloprid 21 %) @ 60 and 120 g a.i. ha(-1) at 7 days interval. Residues of ß-cyfluthrin and imidacloprid in okra were estimated by gas liquid chromatography (GLC) and high performance liquid chromatography (HPLC), respectively. Residues of ß-cyfluthrin were confirmed by gas chromatograph-mass spectrometry (GC-MS) and that of imidacloprid by high performance thin layer chromatography (HPTLC). Half-life periods for ß-cyfluthrin were found to be 0.91 and 0.68 days whereas for imidacloprid these values were observed to be 0.85 and 0.96 days at single and double the application rates, respectively. Residues of ß-cyfluthrin dissipated below its limit of quantification (LOQ) of 0.01 mg kg(-1) after 3 and 5 days at single and double the application dosage, respectively. Similarly, residues of imidacloprid took 5 and 7 days to reach LOQ of 0.01 mg kg(-1), at single and double dosages respectively. Soil samples collected after 15 days of the last application did not show the presence of ß-cyfluthrin and imidacloprid at their detection limit of 0.01 mg kg(-1).
Assuntos
Abelmoschus/química , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Imidazóis/análise , Nitrilas/análise , Nitrocompostos/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Monitoramento Ambiental , Contaminação de Alimentos/análise , Frutas/química , Inseticidas/análise , NeonicotinoidesRESUMO
Dissipation of trifloxystrobin and tebuconazole were studied following two applications of a combination formulation of Nativo 75 WG (trifloxystrobin 25% + tebuconazole 50%) @ 250 and 500 g ha(-1) at 10 days interval. Samples of chili were collected at 0, 1, 3, 5, 7, 10 and 15 days after the last application. Red chili and soil samples were collected after 20 days of last application. Half-life period for trifloxystrobin were found to be 1.81 and 1.58 days and for tebuconazole these values were observed to be 1.37 and 1.41 days, respectively, at single and double the application rates. Trifloxystrobin residues dissipated below its limit of quantification (LOQ) of 0.01 mg kg(-1) after 5 and 7 days, respectively, at single and double the application dosages whereas tebuconazole residues took 7 and 10 days, respectively. Red chili & soil samples collected after 20 days did not reveal the presence of trifloxystrobin and tebuconazole at their determination limit of 0.01 mg kg(-1).
Assuntos
Acetatos/química , Capsicum/química , Fungicidas Industriais/química , Iminas/química , Solo/química , Triazóis/química , Acetatos/análise , Fungicidas Industriais/análise , Meia-Vida , Iminas/análise , Cinética , Metacrilatos/análise , Metacrilatos/química , Modelos Químicos , Poluentes do Solo/análise , Poluentes do Solo/química , Estrobilurinas , Triazóis/análiseRESUMO
Indoxacarb residues were estimated by employing standardized QuEChERS technique in cabbage following three applications of Avant(R) 14.8 EC @ 52.2 and 104.4 g a.i. ha(-1). The average recoveries of indoxacarb on cabbage for fortification levels of 0.01, 0.05 and 0.1 mg kg(-1) were observed to be 83.93, 89.86 and 95.40%, respectively, with relative standard deviation of 1.21, 1.53 and 2.23. The method was also validated with respect to parameters of linearity, precision and limit of quantification (LOQ). The LOQ for cabbage was found to be 0.01 mg kg(-1). The average initial deposits of indoxacarb on cabbage were observed to be 0.18 and 0.39 mg kg(-1), respectively, at single and double the application rate. These indoxacarb residues dissipated below its LOQ of 0.01 mg kg(-1)after 7 and 10 days, respectively, at single and double dosages. Half-life of indoxacarb was observed to be 2.88 and 1.92 days, respectively, at recommended and double the recommended dosages.
Assuntos
Brassica/química , Modelos Químicos , Oxazinas/química , Resíduos de Praguicidas/química , Monitoramento Ambiental , Meia-Vida , Limite de Detecção , Oxazinas/análise , Resíduos de Praguicidas/análise , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/químicaRESUMO
Multi-location supervised field trials were conducted at four different agro climatic locations in India to evaluate the dissipation pattern of deltamethrin on chili. Deltamethrin 10 EC was applied on chili @17.5 and 35 g a.i. ha(-1), samples of green chili were drawn at different time intervals and that of red chili and soil at harvest time and quantified by gas liquid chromatography equipped with electron capture detector. The identity of residues were confirmed by Gas Chromatograph-Mass Spectrophotometer in selective ion monitoring mode in mass range 181, 253 m/z. Limit of quantification of the method was found to be 0.01 mg kg(-1). Half-life of deltamethrin at application rate of 17.5 g a.i. ha(-1) varied from 0.36 to 1.99 days and at double the application rate was found to range from 0.38 to 2.06 days. Residues of deltamethrin were found below its determination limit of 0.01 mg kg(-1) in red chili and soil. On the basis of the data generated, Deltamethrin 10 EC has been registered for use on chili in India and its Maximum Residue Limit has been fixed as 0.05 µg/g.
Assuntos
Capsicum/química , Inseticidas/análise , Nitrilas/análise , Piretrinas/análise , Agricultura , Clima , Monitoramento Ambiental , Poluentes Ambientais/análise , Índia , Cinética , Modelos Químicos , Resíduos de Praguicidas/análiseRESUMO
A semi-dynamic leaching test was carried out for metallurgical wastes and ore samples from the uranium and copper mining industry over a 142 day period using distilled water and 0.1N NaNO(3) as solvents. Laser fluorimetry was used as the analytical technique to determine the total uranium content in the leachates. The cumulative leach fraction (CLF) of uranium release from the samples was calculated to be 0.22, 0.22, 0.07 and 0.39% for rock, uranium tailings, copper kinker ash samples and copper tailings respectively using distilled water as solvent and 0.31, 0.27, 0.05 and 0.59% for the same matrices using 0.1N NaNO(3). The release of mobile uranium fraction was very slow, being faster in the initial stage and then attained a near steady state condition. The diffusion coefficient and bulk release of uranium from the samples have been calculated. The processes governing the release of uranium from these matrices have been identified to be surface wash-off and diffusion. Hence the use of weak solvents (leach out the mobile/exchangeable fraction of uranium) under semi-dynamic conditions aids the determination of leaching parameters and identification of the leaching mechanism for mobile uranium fraction from different matrices by slow leaching processes.
Assuntos
Mineração , Poluentes Radioativos/isolamento & purificação , Urânio/isolamento & purificação , Difusão , Fluorometria , Modelos TeóricosRESUMO
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.
Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Radioisótopos de Césio/análise , Japão , Espectrometria de Massas , Plasma/química , Solo , Poluentes Radioativos do Solo/análise , Urânio/análiseRESUMO
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.
Assuntos
Monitoramento de Radiação , Liberação Nociva de Radioativos , Agricultura , Produtos Agrícolas , Humanos , ÍndiaRESUMO
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 Kd(S) as well as desorption coefficient Kd(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 Kd(S) and Kd(D) values of U were compared with values of Kd(S) and Kd(D) of Cs and Sr and Kd(S)-U in known Fukushima accident contaminated soils reported in the literature for better understanding. It was observed that Kd(S)-U varied from 160 to 5100 L/kg, whereas Kd(D)-U ranged from 200 to 11000 L/kg. Kd(D) was higher than Kd(S) for U in these soils implying irreversibility of the sorption process. Pearson's correlation of Kd(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 Kd(S) and Kd(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.
Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Adsorção , Radioisótopos de Césio/análise , Solo , Poluentes Radioativos do Solo/análise , Urânio/análiseRESUMO
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 60â¯km along the coast were selected for sample collection. The concentrations of U and Th ranged from 1.1 to 737.8⯵gâ¯g-1 and 25.2-12250.6⯵gâ¯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.
Assuntos
Metais Terras Raras , Monitoramento de Radiação , Urânio , Radiação de Fundo , Índia , Metais Terras Raras/análise , Areia , Tório/análise , Urânio/análiseRESUMO
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.