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The study of Total Dissolved Solids (TDS) and concentration distribution of multielements including toxic elements in river–wetland ecosystem at different locations of Satluj River and Harike Wetland were carried out to understand the mobilization behavior of elements including toxic elements. The concentrations of multi-elements in water and sediments were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Instrumental Neutron Activation Analysis (INAA) utilizing reactor neutrons, respectively. The concentration values are found to be within permissible limit set by WHO and BIS. The concentration factors of selected common elements namely Cr, Mn, Fe, Zn and As were evaluated utilizing their corresponding concentrations in water and sediment samples.

Arsenic, which is ubiquitous in nature, was found associated with iron oxides in soils and sediments. Our interest was to utilize the same mechanism for the sorptive removal of arsenic from groundwater. The iron(III) oxides: hematite, goethite, were synthesized, characterized and sorption studies of arsenic [As(III) and As(V)] were carried out in batch mode. For studying the evidence of the interaction between arsenic and iron oxide during the process of sorption, a new electrochemical method was developed. Differential pulse voltammetry (DPV) study indicated that the sorbed arsenic species is redox active on the surface of the sorbent. X-ray photoelectron spectroscopy (XPS) measurement was performed for confirmation of the changes occurring to the oxidation states of iron as well as arsenic after the sorption. XPS studies confirmed that the behavior of arsenic species on hematite/goethite was similar and occurs via a partial redox reaction. During sorption of As(III), a partial oxidation occurs resulting in As(V) species, simultaneously the Fe(III) present in the iron oxide gets reduced to Fe(II). However, during the sorption of As(V), there occurs a Fe(II) oxidation followed by As(V) reduction. Based on the results, a mechanistic scheme for sorption of arsenic on iron(III) oxides as sorbents was proposed.

A sonochemical reduction method of permanganate (MnO4−) was utilized for preparation of manganese dioxide (MnO2) coating on the surface of XAD-4 resin. Characterization of the modified MnO2-coated ...

A radiotracer technique was employed to study the sorption of As(III) and As(V) on chemically synthesized iron oxides: magnetite (Fe

Manganese dioxide (MnO2) synthesized by solid-state reaction was characterized and sorption of As(III) and As(V) on it was studied in batch mode using 76As radiotracer. Arsenic removal efficiency w...

A radiotracer technique was employed to study the sorption of As(III) and As(V) on chemically synthesized iron oxides: magnetite (Fe3O4), goethite (α-FeOOH) and hematite (Fe2O3) by batch equilibration mode. Magnetite and goethite were found to be promising sorbents for arsenic removal and applied to real ground water from West Bengal, India. A solvent extraction method using benzene was applied for the investigation of oxidation state of sorbed arsenic. A sorption mechanism was proposed for interaction of As(III)/As(V) with iron oxides.

Instrumental and preconcentration methods of neutron activation analysis (NAA) have been standardized for the determination of concentration of iodine in grass and cow milk samples, respectively. To study the transfer of iodine from grass to milk, known quantity of grass spiked with potassium iodide solution was fed to a cow. The spiked grass samples and milk samples, obtained from the cow after the ingestion of spiked grass, were collected. Iodine was separated from the milk samples chemically using Dowex 1X8 anion exchange resin. Spiked grass and ion exchange resin samples were neutron irradiated and radioactive assay was carried out using a 45 % relative efficiency HPGe detector coupled to an 8k channel analyzer. Iodine concentrations in spiked grass samples were found to be in the range of 1,487–2,002 mg kg−1. Concentration of iodine in milk after 12 h of feeding the cow with spiked grass was 871 ± 56 μg L−1 which was reduced to 334 ± 32 μg L−1 after 48 h.

Kidney stones obtained from six patients belonging to the stone belt region of India (Punjab) were analyzed for inorganic constituents using instrumental neutron activation analysis (INAA) and energy dispersive X-ray fluorescence (EDXRF) techniques. For INAA, samples were irradiated along with IAEA RM Soil 7 as reference standard in CIRUS reactor, BARC, Mumbai. Gamma activity of irradiated samples was measured using a 45% relative efficiency HPGe detector coupled to 8 k channel analyzer. EDXRF method was used for determination of concentration of Ca. The concentrations of ten elements namely Ca, Na, K, Mn, Co, Cr, Zn, Br, Sm and Cl, are reported and discussed.

Large sample neutron activation analysis of dross from India Government Mint, Mumbai was carried out for quantification of gold (Au) and silver (Ag) using graphite reflector position of Advanced Heavy Water Reactor critical facility at Bhabha Atomic Research Centre, Mumbai. The k 0-based internal monostandard NAA was used to calculate concentration ratios of Au and Ag with respect to sodium (Na), which was used as an internal monostandard. The concentration ratio values of Au to Na of varying mass of dross showed that mass ≥2 g was the representative sample size for analysis. Concentrations of gold and silver were found to be in the range of 200–400 and 1200–1700 mg kg−1, respectively in three different samples.

For standardization of k 0-based instrumental neutron activation analysis, k 0-factors for short-lived nuclides (half-lives—11 s to 37 min) of elements F, Se, Sc, Al, V, Ti, Cu, Ca, Mg, I, and Cl with respect to gold (197Au) were determined using pneumatic carrier facility (PCF) at CIRUS reactor of BARC, Mumbai. Characterization of PCF was carried out by cadmium-ratio method using Au and Zr. The experimental k 0-factors of the isotopes were found to be in good agreement with the recommended k 0-factors in most of the cases, as evident from the values of % error and U-score at 95% confidence level. The method was validated by determining concentrations of elements through their short-lived nuclides in one type of the synthetic multielement standards (SMELS-I) obtained from SCK-CEN, Belgium. The method was also applied for determination of concentrations of some of the elements in two reference materials of IAEA, SL-3, and SL-1.

Arsenic in groundwater is a major concern in many parts of the world and suitable sorbents are required for removal of arsenic from ground water. Removal of arsenic from groundwater has been studied using manganese dioxide, synthesized by solid state reaction of manganese acetate with potassium permanganate. Manganese dioxide was characterized by X-ray diffraction (XRD), zeta potential, surface area, particle size measurements and thermal analysis. XRD measurement showed that the manganese dioxide had α-MnO2 structure. Sorption of As(III) and As(V) on manganese dioxide was studied by radiotracer technique using (76)As radio isotope. Arsenic removal efficiency for both As(III) and As(V) at concentration of 2 mg L(-1) was ∼99% in the pH range of 3-9. The sorption capacities for As(III) and As(V) were ∼60 mg g(-1). Kinetic studies showed that the equilibrium was reached within 30 s. Arsenic sorbed on manganese dioxide was present as As(V) irrespective of initial oxidation state. The presence of Ca(2+), Mg(2+), Cl(-) and SO4(2-) up to a concentration of 1000 mg L(-1) had no significant effect on arsenic sorption. The sorption of arsenic decreased significantly in the presence of phosphate and bicarbonate anions above 10 mg L(-1). Arsenic sorbed on manganese dioxide was desorbed by 0.1M NaOH. Arsenic was effectively removed by manganese dioxide from groundwater samples collected from arsenic contaminated areas of West Bengal, India.

Radioiodine ( 131 I) is one of the radionuclides likely to get released into the atmosphere in case of a reactor accident, though chances of such an accident are very remote due to stringent engineering safety features. If released to the environment during an accident, 131 I may enter the grass→cow→cow milk pathway, leading to increased thyroid dose to those consuming milk, especially infants and children. The estimation of site-specific grass to milk transfer coefficient (F m ) for iodine is essential for an accurate assessment of the radiological hazard to the population in the region surrounding a nuclear power plant. In this study, a method based on the chemical separation of iodine present in grass and cow milk, and subsequent neutron activation analysis (NAA) has been optimized for the determination of stable iodine concentration in grass and cow milk. The method involves preconcentration of iodine from the sample matrix, and determination of iodine by NAA. The detection limit of stable iodine in milk was found to be 1 ng/mL. For the validation of the result, iodine concentration in NIST reference materials was determined simultaneously. The present study has yielded a F m value of 5.6 × 10−3 d/L for dairy farm cows and 6.3 × 10−3 d/L for local breed cows under equilibrium conditions. These results are similar to the values given in International Atomic Energy Agency report (TRS-472). To simulate a rapid deposition of iodine on grass and for the estimation of F m value for an emergency situation, grass grown in the experimental field was sprayed with stable potassium iodide solution and fed to the adopted cows, and the milk samples were collected regularly and analyzed. The F m value for the simulated accidental situation was found to be 3.9 × 10−3 d/L.