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International audience; We investigated 89Zr production induced by deuteron beams on yttrium targets at energies up to Ed = 32 MeV using the stacked-foil activation technique. Cross sections of the following nuclear reactions 89Y(d,2n)89Zr, 89Y(d,3n)88Zr and 89Y(d,x)88Y have also been measured. Based on the measured values, we determined the thick target yields for 89Zr and 88Zr which is the main contaminant associated to the production of 89Zr.

The activity size distributions of the natural radionuclide tracer 7Be in different size fractions ( 9.0 μm) were determined at four different site places in Northern Italy during the four seasons of the year 2011. One cascade impactor operated at the LASA-station considered the reference station and the other used for simultaneous measurements at the three other sites. Three sets of independent samples were collected during every season of the year 2011. The initial activity distribution inverted into smooth size distribution. The model parameters successfully defined to obtain the best fit-curve and two or three modes were resolved, with the predominant fit at the accumulation range. The lowest Activity Median Aerodynamic Diameter (AMAD) values were observed during summer. The AMAD values were anticorrelated with 7Be activities, while they were correlated with Relative Humidity. Similar AMAD values in suburban and urban regions were observed during all periods of the year. AMAD values of 7Be aerosol particles in areas with poor air quality were greater than those at the less polluted environments far from anthropogenic activities regions. This indicates that 7Be AMAD values could be used as an index of air quality conditions in areas like the Po Valley.

Background Knowledge on Bi metabolism in laboratory animals refers to studies at “extreme” exposures, i.e. pharmacologically relevant high-doses (mg kg−1 b.w.) in relation to its medical use, or infinitesimal doses (pg kg−1b.w.) concerning radiobiology protection and radiotherapeutic purposes. There are no specific studies on metabolic patterns of environmental exposure doses (ultratrace level, μg kg−1 b.w.), becoming in this context Bi a “heavy metal fallen into oblivion”. We previously reported the results of the metabolic fate of ultratrace levels of Bi in the blood of rats [ 1 ]. In reference to the same study here we report the results of the retention and tissue binding of Bi with intracellular and molecular components. Methods Animals were intraperitoneally injected with 0.8 μg Bi kg−1 b.w. as 205+206Bi(NO)3, alone or in combination with 59Fe for the radiolabeling of iron proteins. The use of 205+206Bi radiotracer allowed the determination of Bi down to pg fg−1 in biological fluids, tissues, subcellular fractions, and biochemical components isolated by differential centrifugation, size exclusion chromatography, solvent extraction, precipitation, immunoprecipitation and dialysis. Main findings At 24 h post injection the kidney contained by far the highest Bi concentration (10 ng g−1 wt.w.) followed by the thymus, spleen, liver, thyroid, trachea, femur, lung, adrenal gland, stomach, duodenum and pancreas (0.1 to 1.3 ng g−1 wt.w.). Brain and testis showed smaller but consistently significant concentrations of the element (0.03 ng g−1 wt.w). Urine was the predominant route of excretion. Intracellularly, liver, kidney, spleen, testis, and brain cytosols displayed the highest percentages (35%–58%) of Bi of homogenates. Liver and testis nuclei were the organelles with the highest Bi content (24 % and 27 %). However, when the recovered Bi of the liver was recorded as percent of total recovered Bi divided by percent of total recovered protein the lysosomes showed the highest relative specific activity than in other fractions. In the brain subcellular fractions Bi was incorporated by neuro-structures with the protein and not lipidic fraction of the myelin retaining 18 % of Bi of the total homogenate. After the liver intra-subcellular fractionation: (i) 65 % of the nuclear Bi was associated with the protein fraction of the nuclear membranes and 35 % with the bulk chromatin bound to non-histone and DNA fractions; (ii) about 50 % of the mitochondrial Bi was associated with inner and outer membranes being the other half recovered in the intramitochondrial matrix; (iii) in microsomes Bi showed a high affinity (close to 90 %) for the membranous components (rough and smooth membranes); (iv) In the liver cytosol three pools of Bi-binding proteins (molecular size > 300 kDa, 70 kDa and 10 kDa) were observed with ferritin and metallothionein–like protein identified as Bi-binding biomolecules. Three similar protein pools were also observed in the kidney cytosol. However, the amount of Bi, calculated in percent of the total cytosolic Bi, were significantly different compared to the corresponding pools of the liver cytosol. Conclusions At the best of our knowledge the present paper represents the first in vivo study, on the basis of an environmental toxicology approach, aiming at describing retention and binding of Bi in the rat at tissue, intracellular and molecular levels.

Background The number of the applications of bismuth (Bi) is rapidly and remarkably increasing, enhancing the chance to increase the levels to which humans are normally daily exposed. The interest to Bi comes also from the potential of Bi-based nanoparticles (BiNPs) for industrial and biomedical purposes. Like other metal-based NPs used in nanomedicine, BiNPs may release ultratrace amounts of Bi ions when injected. The metabolic fate and toxicity of these ions still needs to be evaluated. At present, knowledge of Bi metabolism in laboratory animals refers almost solely to studies under unnatural “extreme” exposures, i.e. pharmacologically relevant high-doses (up to thousand mg kg−1) in relation to its medical use, or infinitesimal-doses (pg kg−1 as non-carrier-added Bi radioisotopes) for radiobiology protection, diagnostic and radiotherapeutic purposes. No specific study exists on the “metabolic patterns” in animal models exposed to levels of Bi, i.e. at “environmental dose exposure” that reflect the human daily exposure (μg kg−1). Methodology Rats were intraperitoneally injected with 0.8 μg Bi kg−1 bw as 205+206Bi(NO)3 alone or in combination with 59Fe for radiolabelling of iron proteins. The use of 205+206Bi radiotracers allowed the detection and measurement down to pg fg−1 of the element in the blood biochemical compartments and protein fractions as isolated by differential centrifugation, size exclusion- and ion exchange chromatography, electrophoresis, solvent extraction, precipitation and dialysis. Results 24 h after the administration, the blood concentration of Bi was 0.18 ng mL−1, with a repartition plasma/red blod cells (RBC) in a ratio of 2:1. Elution profiles of plasma from gel filtration on Sephadex G-150 showed four pools of Bi-binder proteins with different molecular sizes (> 300 kDa, 160 kDa, 70 kDa and Conclusions On the basis of an environmental biochemical toxicology approach, we have undertaken a study on the metabolic patterns of Bi3+ ions in rats at tissue, subcellular and molecular level with the identification of cellular Bi-binding components. As a first part of the study the present work reports the results concerned with the metabolic fate of ultratrace levels of 205+206Bi(NO)3 in the blood.

Non linear modelling of data in photomineralization kinetics of organic micropollutants, by photocatalytic membranes immobilizing semiconductors (TiO2 particularly) has been previously applied to methane, phenol and to 2,4-dichlorophenol as model molecules, by using a four parameters kinetic modelling based on substrate disappearance and total organic carbon (TOC) in laboratory scale experiments, as a function of initial concentration of substrate and of irradiance. In the present paper, the photocatalytic degradation of diclofenac as model molecule was investigated in a pilot plant module, fitted with 2–3 concentric membranes. Maximum allowable quantum efficiencies corresponded to equal distances between 3 membranes immobilizing photocatalyst. This arrangement fully behaves as if a photocatalyst nanopowder would be homogeneously suspended in the reactor, but obviating all drawbacks of a nanopowder suspension.

Deuteron-induced nuclear reactions for the generation of 103Pd were investigated using the stacked-foil activation technique on rhodium targets at deuteron energies up to Ed=33MeV. The excitation functions of the reactions 103Rh(d,xn)101,103Pd, 103Rh(d,x)100g,cum,101m,g,102m,gRh and 103Rh(d,2p)103Ru have been measured, and the Thick-Target Yield for 103Pd has been calculated.

Proton-induced nuclear reactions for generation of (99)Mo and (99m)Tc radionuclides were investigated using the stacked-foil activation technique on 99.05% enriched (100)Mo targets at energies up to Ep=21MeV. Excitation functions of the reactions (100)Mo(p,x)(99)Mo and (100)Mo(p,2n)(99m)Tc have been measured.

Analyses of 131I, 137Cs and 134Cs in airborne aerosols were carried out in daily samples at two different sites of investigation: Thessaloniki, Greece (40° N) and Milan, Italy (45° N) after the Fukushima accident during the period of March–April, 2011. The radionuclide concentrations were determined and studied as a function of time. The 131I concentration in air over Milan and Thessaloniki peaked on April 3–4, 2011, with observed activities 467 μBq m−3 and 497 μBq m−3, respectively. The 134Cs/137Cs activity ratio values in air were around 1 in both regions, related to the burn-up history of the damaged nuclear fuel of the destroyed nuclear reactor. The high 131I/137Cs ratio, observed during the first days after the accident, followed by lower values during the following days, reflects not only the initial release ratio but also the different volatility, attachment and removal of the two isotopes during transportation due to their different physico-chemical properties. No artificial radionuclides could be detected in air after April 28, 2011 in both regions of investigation. The different maxima of airborne 131I and 134,137Cs in these two regions were related to long-range air mass transport from Japan, across the Pacific and to Central Europe. Analysis of backward trajectories was used to confirm the arrival of artificial radionuclides following atmospheric transport and processing. HYSPLIT backward trajectories were applied for the interpretation of activity variations of measured radionuclides.

The radionuclides 131 I, 137 Cs and 134 Cs were observed in the Milano region (45°) of Italy early after the nuclear accident in Fukushima, Japan. Increased atmospheric radioactivity was observed on an air filter taken on 30 March 2011, while the maximum activity of 467 μBq m −3 for 131 I was recorded at April 3–4, 2011. The first evidence of Fukushima fallout was confirmed with 131 I and 137 Cs measured in precipitation at two sampling sites at Milano on 28 March, 2011, with the concentrations of 131 I and 137 Cs in the rainwater equal to 0.89 Bq L −1 and 0.12 Bq L −1 , respectively. A sample of dry deposition that was collected 9 days after the first rainfall event of 27–28 March, 2011 showed that the dry deposition was more effective in the case of 137 Cs than it was for 131 I, probably because iodine was mainly in gaseous form whereas caesium was rapidly bound to aerosols and thus highly subject to dry deposition. The relatively high observed values of 137 Cs in grass, soil and fresh goat and cow milk samples were probably from Chernobyl fallout and global fallout from past nuclear tests rather than from the Fukushima accident. Finally, a dose assessment for the region of investigation showed clearly that the detected activities in all environmental samples were very far below levels of concern.

Deuteron-induced nuclear reactions for generation of no-carrier-added Lu radionuclides were investigated using the stacked-foil activation technique on natural Yb targets at energies up to E(d)=18.18 MeV. Excitation functions of the reactions (nat)Yb(d,xn)(169,170,171,172,173,174g,174m,176m,177g)Lu and (nat)Yb(d,pxn)(169,175,177)Yb have been measured, among them three ((169)Lu, (174m)Lu and (176m)Lu) are reported for the first time. The upper limit of the contamination from the long-lived metastable level (177m)Lu was evaluated too. Thick-target yields for all investigated radionuclides are calculated.

Deuteron-induced nuclear reactions for generation of no-carrier-added (NCA) Lu isotopes were investigated using the stacked-foil activation technique on natural Yb targets at energies up to E d = 18.18 MeV. The decay curve of 177 Yb, the growth curve of the cumulative (direct and indirect) and the direct production of 177g Lu were determined. The analysis of these curves conducts to the evidence that the predominant route for the production of 177g Lu is the indirect reaction 176 Yb(d,p) 177 Yb, which decays to 177g Lu. In the spectra acquired one year from the EOB the γ lines of 177m Lu are not evident. A comparison between the calculated activity of 177g Lu produced with a cyclotron and with a nuclear reactor is given.

(90)Y is one of the most useful radionuclides for radioimmunotherapeutic applications and has a half-life (t(1/2)=64.14h) suitable for most therapeutic applications, beta particles of high energy and decays to a stable daughter. It is significant that (90)Y is available conveniently and inexpensively from a radionuclide "generator" by decay of its parent, (90)Sr. Nevertheless, current and planned clinical applications with [(90)Y] labelled compounds employ activity levels that cannot be readily obtained from an in-house generator, but from commercial sources. We have evaluated Eichrom's Sr-resin, either as an "in-house" generator or as a fast QC method for analysis of (90)Y solutions. In particular, for the development as a generator, we investigated the percentage of the radio-Sr in the first 8M HNO(3) eluate: in this fraction the concentration of (90)Sr must be smaller than 10(-5)% (recommendations of the International Commission on Radiological Protection). For evaluation as a rapid QC method, we analyzed the concentration of (90)Y in all the fractions containing "only" radio-Sr: (90)Y should not be present in these eluates. After the collection of beta(-) and gamma spectra and analysis of them, we concluded that commercial Sr-resin minicolumn cannot give us the results expected; we developed an in-house system loaded with 4mL of Sr-resin which gave better results as a generator and a rapid QC method.

An empirical equation was developed for the count rate of a cylindrical radioactive source by an HPGe detector as a function of the volume and the height of the source. The equation can be used to calculate the height of the cylinder, which will yield maximum count rate for a known volume of environmental source.

A method is described to locate a radioactive point source in a lung using a commercial array of lung detectors. The method takes advantage of the fact that modern commercial systems consist of several Ge detectors, each connected to a multi-channel analyzer, and the information from each detector can be analyzed separately. The system is calibrated with point sources placed in various locations in the lungs of a phantom. A vector method is presented for determining which of the calibration locations in the phantom is closest to the location of the unknown point source. It has been shown that the accuracy of the method increases with increasing number of the vector dimensions. A higher dimensionality can be achieved by analyzing counts of several gamma lines or by using more detectors.

The short-lived (12.7h half-life) (64)Cu radioisotope is both a beta(+) and a beta(-) emitter. This property makes (64)Cu a promising candidate for novel medical applications, since it can be used simultaneously for therapeutic application of radiolabelled biomolecules and for diagnosis with PET. Following previous work on (64)Cu production by deuteron irradiation of natural zinc, we report here the production of this radioisotope by deuteron irradiation of enriched (64)Zn. In addition, yields of other radioisotopes such as (61)Cu, (67)Cu, (65)Zn, (69m)Zn, (66)Ga and (67)Ga, which were co-produced in this process, were also measured. The evaporation code ALICE-91 and the transport code SRIM 2003 were used to determine the excitation functions and the stopping power, respectively. All the nuclear reactions yielding the above-mentioned radioisotopes were taken into account in the calculations both for the natural and enriched Zn targets. The experimental and calculated yields were shown to be in reasonable agreement. The work was carried out at the Scanditronix MC-40 Cyclotron of the Institute for Health and Consumer Protection of the Joint Research Centre of the European Commission (Ispra site, Italy). The irradiations were carried out with 19.5 MeV deuterons, the maximum deuteron energy obtainable with the MC-40 cyclotron.

Two widespread misconceptions regarding Tc are dealt with. First, it is shown that although primordial Tc has decayed completely, Tc is still present in nature due to natural processes, in addition to substantial man-made quantities. Thus, Tc cannot be considered as a purely artificial element. Second, it is shown that 99mTc from 99Mo/99mTc generators is certainly not carrier-free (CF) and that, “no-carrier-added” (NCA) is a more appropriate designation. As a quantitative measure of the amount of long-lived 99gTc carrier present in 99mTc preparations from generators, the Isotope Dilution Factor (IDF) is used and calculated for some practical situations.

In the measurement of natural occurring radioactive material (NORM) concentrations of 40 K , 232 Th and 238 U are measured by passive gamma ray spectrometry with either HPGe or NaI(Tl) detectors. 40 K is measured through its 1460.8 keV γ line. However, till now it has been ignored that this line is mixed with the 1459.2 keV line of 228 Ac from the chain of 232 Th . A correction must be made for this contribution. All the data in literature has wrong data about the concentration of 40 K although in many cases the error is less than 1%. However, there are cases of considerably higher errors. It should be emphasized that even if the correction in 40 K concentration is large the correction of external dose index is negligible due to the higher weighing factor for 232 Th than for 40 K (by at least a factor of 10).

A novel method for production of No-Carrier-Added 64 Cu and 66,67 Ga has been developed, based on reactions induced by deuterons up to 19 MeV on Zn target. HPGe and beta (by LSC) spectrometries proved very effective to determine radionuclidic purity of 64 Cu and 66,67 Ga fractions. Experimental specific activity for 64 Cu was measured by ET-AAS and was of the order of 700 MBq · μg −1 . Radiochemical yields for 64 Cu and 66,67 Ga were >80% and >99%.

The radioisotopes of ruthenium (103Ru and 106Ru) are abundant fission products and represent a radiological risk for the population in case of nuclear accidents. Few biokinetic studies have been performed on humans up to now and consequently the current model recommended by ICRP for ruthenium is derived mainly by extrapolation from animal data. The stable isotope 101Ru and proton activation analysis have been used to study the biokinetics of Ru in blood plasma samples taken during 8 studies in three healthy volunteers. The results obtained demonstrated that complexed Ru (in the form of citrate Ru(IV) complexes) is cleared from blood plasma very rapidly (characteristic half time of 17+/-2 min), while inorganic Ru remains longer in the systemic circulation, and is transferred to other organs and/or excreted with a biological half time of 23+/-2h. Good reproducibility of the clearance curves indicated no evidence of inter- or intra-individual variability when the same Ru solution was injected in repeated experiments to different subjects.

There is much interest in understanding the biokinetics of zirconium in humans due to the potential radiological risk represented by the radionuclide 95Zr and by its daughter 95Nb. Despite the significance of zirconium, few data are available on the actual biokinetics of zirconium in humans. Accordingly the biokinetic model currently recommended by ICRP for this element is based mainly on data from animal experiments. In this study, the use of the stable isotopes 90Zr and 96Zr as tracers has enabled the conduct of 6 biokinetic investigations in 3 healthy volunteers. These studies have provided new valuable information about intestinal absorption and kinetics in blood plasma of zirconium and have been used for the set-up of a more realistic compartmental model with possible applications for dosimetric purposes.

Despite the cyclotron production method and the efficiency of the radiochemical procedures adopted, the long-lived radio-isotopic impurity 202Tl is always present in [201Tl]-labelled radio-pharmaceuticals, together with other short-lived impurities like, 200Tl. Rapid determination of the 202Tl impurity, can be achieved using HPGe gamma spectrometry and a detector shielded by a 5 mm thick envelope of lead. In this way, dead-time correction errors, Compton and X-ray background, are very efficiently avoided and suppressed. The same method could be applied routinely in nuclear medicine, to determine the radioisotopic purity of 201Tl by means of an ionisation chamber dose calibrator.

This work describes the method adopted in our laboratories, to produce 94gTc, 95gTc, 95mTc and 96gTc radionuclides via proton-cyclotron irradiation on molybdenum targets of natural isotopic composition. A new set of experimental thin-target excitation functions and "effective" cross-sections for direct natMo(p,xn)(A)Tc [with A = 94, 95, 95, 96] nuclear reactions, with incident proton energy in the range from threshold up to 44 MeV is presented. Some definitions of the equations used and nuclear data traceability are reported. Thick-target yield values were calculated and optimised, by numerical fitting and integration of the measured excitation functions. These values allow optimisation of production yield of one radionuclide, minimising at the same time the yield of the others. Radiochemical separation on NCA technetium radionuclides from both molybdenum target and niobium, zirconium and yttrium radioactive by-products is reported. Quality control tests of the radiotracers were developed for the applications envisaged in environmental metallo-biochemical toxicology.

Thin- and thick-target excitation functions of 188,189,191 Pt radionuclides were experimentally determined by cyclotron irradiation, using nuclear reactions nat Os(α,xn) in the energy range up to 38 MeV with the Scanditronix-MC40 Cyclotron of the Joint Research Centre-Ispra, VA (Italy) of the European Communities. Radionuclidic, radiochemical and chemical purities have been also measured by use of analytical and radioanalytical techniques. In this paper, the result of the experimental thick- and thin-target excitation functions of 188,189,191 Pt radiotracers, produced via nat Os(α,xn) reactions, are presented. The data are of relevant interest for optimising cyclotron production of platinum radionuclides to be used as radiotracers for metallo-biochemical, biomedical, toxicological and environmental studies. In this paper, we will present the analytical and radioanalytical methods that have been developed to determine the amount of isotopic carrier and the SA(NCA) in the case of 188 Pt, 191 Pt, to be used for ‘multiple labelling’ experiments, by: high resolution γ-spectrometry, β-spectrometry by liquid scintillation counting, neutron activation analysis, FL-AAS, and ICP-OES. Moreover, some preliminary biological applications were carried out in order to determine the cyto-toxicology of different chemical forms of platinum.

Both essential and toxic elements are present in the biosphere in different inorganic and organo–metallic forms. Some trace elements like Cr, Cu, Mn, Rb, Se, Tl, V, Zn are essential to human life and are present in human tissues, body fluids, cells and sub-cellular components, bonded to enzymes, proteins, etc. Many trace elements are introduced daily in the body in amounts ranging from ng to μg per kg. A powerful tool to set up analytical procedures, to evaluate the chemical separation yield and to follow the fate of different chemical forms of ultra-trace elements on living organisms is the use of ‘high specific activity’ radioactive tracers (RT). Amongst the more effective RTs for radio-analytical chemistry, there are the short-lived medium γ-energy emitters. A review of the last 25 years in the field of both cyclotron and nuclear reactors producing high specific activity radionuclides in radio-analytical chemistry is presented. As, Au, Cu, Ga, Mn, Np, Pd, Pt, Rb, Rh, Sb, Te, Ti, Tl, V, etc., γ- and β emitting RTs have had interesting applications in the ultra-trace metallo-toxicology field. High-resolution γ-spectrometry by HPGe detection and β spectrometry by liquid scintillation counting, have been used, hyphenated with ‘elemental analysis’ radio-analytical and analytical techniques. The ‘high specific activity’ of the No Carrier Added RTs is the ‘key factor’ of this powerful radio analytical technique.

The possibility to measure the flux of thermal neutrons by activation of gold of unknown weight using the counts of both 199 Au and 198 Au gamma emission was studied. It can be used for impure gold monitors or when the activated sample has gold in it. The possible interferences are discussed.

First results are given from the comparison of experimental values and model calculations on accelerator-produced high specific activity radionuclides in no-carrier-added (NCA) form. The relevant radioisotopes are: 64 Cu, produced by nat Zn(d, αx n) and nat Zn(d,2p) reactions, for simultaneous positron/negatron metabolic radiotherapy and PET imaging; 66 Ga high-energy positron emitter (4.2 MeV), produced by nat Zn(d, x n) reactions, for metabolic radiotherapy and for PET; 186g Re, produced by 186 W(p,n) and 186 W(d,2n) reactions, for negatron (1.1 MeV) metabolic radiotherapy; 211 At/ 211 Po, produced by 209 Bi( α ,2n) reaction (with spike of gamma emitter 210 At produced by 209 Bi( α ,3n) reaction) and 225 Ac/ 213 Bi/ 213 Po, produced by 226 Ra(p,2n) reaction, both for high-LET radiotherapy.

Iodine-125 is a radioisotopic impurity “always” present in iodine-123, produced by nuclear reactions induced either on natural or “highly” enriched targets. Liquid scintillation counting is a very sensitive tool to determine low level impurities of both low energy electrons and photons in aqueous and organic solutions of radiopharmaceutical compounds. With this technique it was possible to determine, on commercial samples, that the content of 125I was of the order of not less than 0.1% for 123I produced via 127I(p,5n) reactions and not less than 0.01% for 123I produced via “highly” enriched 124Xe(p,X) nuclear reactions.

High specific activity radionuclides are a powerful tool for labeling a large range of inorganic and metallorganic species that are present in the environment at very low concentrations. In order to study the environmental impact of trace elements (TE) on the humans, it is of fundamental importance to carry out both in vitro and in vivo experiments on cell cultures and laboratory animals, with concentrations of these TE representative of the actual long-term and low-level exposures. In order to obtain these radiotracers in a very high specific activity form, it is necessary: (a) to optimize the production method by either charged particle accelerator (normally cyclotron) or nuclear reactor irradiation, (b) to separate and purify them from the irradiated target by chemical or physicochemical methods, without the addition of inactive carriers (i.e., the so-called no carrier added form), (c) to carry out a series of analytical and radioanalytical tests, in order to verify the chemical, radiochemical, and radionuclide purities of the tracer or labeled compound under investigation. Some production, separation, purification, and quality control methods developed for the two cyclotron-produced radionuclides 52gMn and 48V will be presented and discussed.

In order to find the optimal granularity of the electromagnetic section of a hadronic calorimeter, with tungsten or uranium absorbers, lateral shower extension is to be defined. A test was performed in t9 beam at the CERN-PS (proton synchrotron) with incoming electron energies of 2, 4 and 6 GeV. It was found that in the investigated radial region, the structure of the lateral shower development has two components.