Low-level 226Ra determination in groundwater by SF-ICP-MS: optimization of separation and pre-concentration methods

Inductively coupled plasma mass spectrometry (ICP-MS) techniques have been widely used for analysis of long-lived environmental radionuclides. In this paper, we present an optimization of the sector field (SF)-ICP-MS technique for the analysis of 226Ra in groundwater samples using a method of pre-concentration of radium in water samples. The separation protocol and a sequential application of ion exchange and extraction chromatography have been optimized, and related polyatomic interferences and matrix effects affecting the 226Ra signal were investigated. Analyzing 12 replicates (water spiking at 22 fg g−1 of 226Ra), the 226Ra recovery efficiency close to 100 % has been obtained. The instrumental 226Ra detection limit of 0.09 fg g−1 (3σ criterion) and the absolute detection limit of 0.05 fg in a 25-mL groundwater sample have been reached. An optimization of the radium separation method and a pre-concentration of radium in groundwater samples led to high radium recoveries, almost up to 100 %. The same could be said with respect to the separation of the interfering elements, important for the quantitative 226Ra analysis by SF-ICP-MS. The improvements in the separation and pre-concentration techniques also helped to improve the 226Ra detection limit down to 0.05 fg/25 mL of groundwater sample

Dissolved Nutrients from Submarine Groundwater in Flic en Flac Lagoon, Mauritius

The aim of this study was to investigate dissolved nutrients in a submarine groundwater discharge (SGD) in Flic en Flac lagoon on the west coast of the volcanic island of Mauritius. The SGD enters Flic en Flac lagoon through a thin blanket of unconsolidated sediment through a fracture system and is concentrated along the irregular surface of the buried rock. The results show that the major inputs of dissolved nitrate and phosphate in Flic en Flac lagoon arise from agricultural and domestic sources during periods of heavy rain. Dissolved nitrate (150-470 µg/l) and phosphate (10-115 µg/l) concentrations in the SGD, lagoon and offshore in the Flic en Flac region fell within the range of seawater values in the Pacific region. Rainfall caused dissolved nitrate and phosphate transfer through groundwater conduits in the coralline basement of the lagoon, delivering a significant discharge during the cyclone season in summer. The lagoon is subjected to diffuse SGD flows which may contribute to its high dissolved nutrient values. This will lead to a reduction in the lagoon’s assimilative capacity, exacerbating the problem of excessive nutrient input and associated eutrophication in the lagoon. The submarine groundwater discharge thus merits consideration in Mauritian coastal zone management and similar tropical volcanic lagoonal systems

Estimation of the radioactive source dispersion from Fukushima nuclear power plant accident

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A century of warfare shoots holes in anti-Caulerpa campaign

Effort to have all varieties of the marine alga Caulerpa taxifolia listed as noxious weeds hinges on the argument that the alga's proliferation in the Mediterranean Sea is a cause and not a consequence of environmental degradation. Until now, the occurrence of two populations in a pristine part of the northern Mediterranean near the island of Porquerolles has upheld this claim. Here we show that the alga's development at Porquerolles is indeed a consequence of environmental degradation caused by military weapons' impacts on seagrass beds during the last century. The available data show that substratum enrichment plays a key role in fostering development of Caulerpa, irrespective of whether this results directly from pollution or from the impacts of pollution and other anthropogenic factors on benthic vegetation cover

Estimation of the time-dependent radioactive source-term from the Fukushima nuclear power plant accident using atmospheric transport modelling

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Ground gamma-ray survey of the Solforata gas discharge area, Alban Hills-Italy: A comparison between field and laboratory measurements

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Mineralogy, geochemistry and classification of the new Smolenice iron meteorite from Slovakia

Abstract: A single 13.95 kg mass of a slightly weathered iron meteorite was found in the forest near Smolenice (48°31.2’N, 17°23.9’E; Trnava County, Slovakia). The bulk chemical composition (in wt. %) is: Fe 88.78, Ni 8.16, Co 0.38, P 0.05, S˂0.006 and (in μg/g): Ge˂0.18, Ir 1.67, Ga 1.80, Cr 87.3, Cu 135.1, As 4.52, Mo 5.82, Sn 1.53, W 0.56, Re 0.18, Ru 3.56, Rh 0.90, Pd 4.12, Pt 5.35, Au 1.19, Zn˂5, B˂0.68, Pb˂0.06. Bulk geochemistry, and Ni, Ga, Ge and Ir contents in particular suggest that the meteorite is an octahedrite belonging to the IVA group. The average thickness of kamacite lamellae is 0.22 mm, ranking it as fine octahedrite (Of). The mineral composition is simple, the most abundant minerals being iron (kamacite) (5.16–7.36 wt. % Ni) followed by taenite (16.73–33.93 wt. % Ni). Troilite nodules and daubréelite inclusions and thin veinlets are rare. The Widmanstätten pattern is uniform across the meteorite and plessite structure is developed locally. Analyses of cosmogenic radionuclides (14C and 26Al) indicate that the radius of the Smolenice meteorite could be 30±10 cm and its terrestrial age 11±2 kyr

Certified reference material IAEA-418: 129I in Mediterranean Sea water

A certified reference material designed for the determination of 129I in seawater, IAEA-418 (Mediterranean Sea water) is described and the results of certification are presented. The median of 129I concentration with 95% confidence interval was chosen as the most reliable estimates of the true value. The median, given as the certified value, is 2.28 × 108 atom L−1 (95% confidence interval is (2.16–2.73) 108 atom L−1), or 3.19 × 10−7 Bq L−1 (95% confidence interval is (3.02–3.82) × 10−7 Bq L−1). The material is intended to be used for standardization procedures applied in accelerator mass spectrometric laboratories. It is available in 1 L units and may be ordered via IAEA web side (www.iaea.org).The IAEA is grateful for the support provided to its Marine Environment Laboratories by the Government of the Principality of Monaco. PPP acknowledges a support provided by the EU Research & Development Operational Program funded by the ERDF (project No. 26240220004).Peer reviewe

New Analytical Technologies for New Science

Recent developments in ultra low-level radionuclide analyses using radiometrics and mass spectrometry methods, which have had important impacts on new applications of radionuclides as tracers of environmental processes are discussed