Innovative methods for determination of Sr and Cs in soil samples based on effective radiochemical separation and beta-counting.

- Innovative methods were developed for direct Sr and Cs determination in soils by radiochemical separation and β-counting. Studies focused on: (1) the suitability of PEG to remove silica by coating, (2) the decontamination effect of Cs from K, (3) iron elimination with Microthene-TOA column instead of oxalate complex, and (4) the effective separation of Y and Sr from Pb by a Microthene-TOA column which made the direct Sr determination possible in less time with just one resin-column. The methods were validated by analysing the IAEA reference materials, showing good agreement with the recommended values.

An innovative method for determination of uranium isotopes in soils by alpha-spectrometry coupled with Microthene-TOPO column separation.

In the new procedure for determination of uranium isotopes by α-spectrometry, silica in the leachate of fused soil samples was coated with polyethylene glycol 2000 and eliminated through filtration, and uranium isotopes were separated from other α-emitters with a Microthene-TOPO column and electrodeposited on a stainless steel disc for measurement. It was observed that treatment with HF has negligible contribution on the release of uranium from the leachate containing silicates, so the use of HF for mineralization can be avoided. The reference material IAEA-315 marine sediment was analysed, and the obtained U, U and U concentrations are in good agreement with the certified values.

Radioecological studies of the main naturally occurring radionuclides in the area of Gela Phosphate Industry (Italy) through radioanalytical separation and measurement techniques.

Radioecological studies have been carried out in area of Gela Phosphate Industry. As a part of the project, some achievements have been described in the paper, including: (1) determination of the activity concentrations of Po, Pb, uranium, and radium isotopes in phosphogypsum, phosphoric acid, soil, and marine sediment, (2) inventory estimation of the NORM in the residual product and by-product, and (3) the radioecological investigation and evaluation on the NORM contamination in the sea area of Gela. The obtained data showed that the Po, Pb, uranium, and radium isotope contamination due to discharge of phosphogypsum from 1960s to 1990s is not observable through sediment analyses.

Sensitive and accurate methods for determination of low activity level of Sr and Cs in grass/vegetable samples.

Sensitive, precise and accurate methods for determination of low activity level of Sr and Cs in grass/vegetable samples by a low background β-counter were developed. The method for Sr determination was based on coprecipitation as carbonate, elimination of Bi and iron with a Microthene-TOA column, separation of Y with a Microthene-HDEHP column, and source preparation as Y(CO). The method for Cs determination was based on Cs adsorption on ammonium molybdophosphate and precipitation as CsBiI for source preparation.

The fate of the main naturally occurring radionuclides in mussels (Mytilus edulis) and their radiological impact on human beings.

A comprehensive study was made on the activity concentrations, concentration factors, and radiation exposure impact of the main naturally occurring radionuclides in blue mussels collected in the Mediterranean Sea. The results showed that the concentrations of the measured radionuclides were site-specific and all detectable in gram-size samples of the soft tissues of the mussels, especially, some activity concentrations can reach as high as 16.8-102 Bq kg for Po, 16.

Simultaneous determination of Po and Pb in solid samples: A new method for Pb determination.

A new method has been developed for determination of Pb and a simultaneous determination of Po and Pb was performed in solid samples. Po and Pb were sequentially leached at 250 °C with HNO+HF, HClO and HCl. Twenty percent of the leaching solution was used for Po determination by α-spectrometry after Po spontaneous deposition on a silver disc from a weak HCl solution that containing hydroxylamine hydrochloride, sodium citrate and Po tracer.

A radiological survey and the impact of the elevated concentrations of (210)Pb and (210)Po released from the iron- and steel-making plant ILVA Taranto (Italy) on the environment and the public.

A radiological survey on the iron- and steel-making plant ILVA Taranto (Italy) was mainly focused on contamination source-term investigation and exposure impact evaluation of the volatile radionuclides 210Po and 210Pb. The activity concentrations of 210Po and 210Pb in the raw materials, dust particles, surficial soils and atmospheric particulate samples collected in the area of ILVA Taranto were determined. The results showed that the activity concentrations in the raw materials were in the range of 3.

Determination of radium isotopes in environmental samples by gamma spectrometry, liquid scintillation counting and alpha spectrometry: a review of analytical methodology.

Radium (Ra) isotopes are important from the viewpoints of radiation protection and environmental protection. Their high toxicity has stimulated the continuing interest in methodology research for determination of Ra isotopes in various media. In this paper, the three most routinely used analytical techniques for Ra isotope determination in biological and environmental samples, i.

Concentrations of 238U, 234U, 235U, 232Th, 230Th, 228Th, 226Ra, 228Ra, 224Ra, 210Po, 210Pb and 212Pb in drinking water in Italy: reconciling safety standards based on measurements of gross alpha and beta.

Some important naturally occurring alpha- and beta-radionuclides in drinking water samples collected in Italy were determined and the radiological quality evaluated. The mean activity concentrations (mBqL(-1)) of the radionuclides in the water samples were almost in the order: 26+/-36 ((234)U)>21+/-30 ((238)U)>8.9+/-15 ((226)Ra)>4.

Determination of thorium isotopes in mineral and environmental water and soil samples by alpha-spectrometry and the fate of thorium in water.

A method has been developed for determination of thorium isotopes in water and soil samples by alpha-spectrometry. After fusion with Na(2)CO(3) and Na(2)O(2) at 600 degrees C, soil samples were leached with HNO(3) and HCl. Thorium in water sample or in soil leaching solution was coprecipitated together with iron (III) as hydroxides and/or carbonates at pH 9 with ammonia solution, separated from uranium and other alpha-emitters by a Microthene-TOPO (tri-octyl-phosphine oxide) chromatographic column, electrodeposited on a stainless steel disk, and measured by alpha-spectrometry.

Estimation of radiation doses to members of the public in Italy from intakes of some important naturally occurring radionuclides (238U, 234U, 235U, 226Ra, 228Ra, 224Ra and (210)Po) in drinking water.

The radiological quality in some samples of drinking water collected in Italy has been evaluated in the paper. As far as the measured alpha or beta radionuclides are concerned, the doses for all the analysed samples of drinking water are in the range of 1.80-36.

Determination of 210Pb and 210Po in soil or rock samples containing refractory matrices.

A new method has been developed for determination of (210)Pb and (210)Po in soil or rock samples containing refractory matrices. The samples were first fused with Na(2)CO(3) and Na(2)O(2) at 600 degrees C for pre-treatment and then (210)Pb and (210)Po were sequentially leached out at 200-250 degrees C with HNO(3)+HF, HClO(4) and HCl. About 10% of the leaching solution was used for (210)Po determination, carried out by spontaneous deposition of polonium on a silver disc from a weakly acidic solution that contained hydroxylamine hydrochloride, sodium citrate and (209)Po tracer, measurement being made by alpha-spectrometry.

Concentration and characteristics of depleted uranium in biological and water samples collected in Bosnia and Herzegovina.

During Balkan conflicts in 1994-1995, depleted uranium (DU) ordnance was employed and was left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Bosnia and Herzegovina, radiological survey of DU in biological and water samples were carried out over the period 12-24 October 2002.

Concentration and characteristics of depleted uranium in water, air and biological samples collected in Serbia and Montenegro.

During the Balkan conflicts, in 1995 and 1999, depleted uranium (DU) rounds were employed and were left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Serbia and Montenegro, radiological surveys of DU in water, air and biological samples were carried out over the period 27 October-5 November 2001.

Distribution coefficients of polonium between 5% TOPO in toluene and aqueous hydrochloric and nitric acids.

The distribution coefficients (D) of polonium between 5% TOPO in toluene and aqueous hydrochloric and nitric acids have been studied. Results show that: (1) D values are ranged from 61.3 to 331 when the acidities vary from 0.