In this paper, a case study is reported referring to an investigation carried out to evaluate the radioactivity content, and thus the radiological health risk for humans related to external exposure, in construction materials of the Giudecca urban section (Bova, Reggio Calabria, Italy). The analysis of natural radionuclides contents was performed through X-ray Fluorescence (XRF) spectrometry measurements and the massic concentration (in µg/g) of U, Th, and K was then converted into activity concentration according to Dragovic’s formula. The absorbed γ-dose rate and the Annual Effective Dose Equivalent (AEDE) outdoor radiological hazard indices were then assessed.

In our study, we introduce a model of a downscaled house with building materials containing technologically enhanced naturally occurring radioactive materials (TENORM). The house has an approximate volume of 1 m 3 , and its interior is equipped with detectors. The TENORM used are phosphorite metasilicates, which were sourced from the Crotone region in Italy. Our findings reveal that the presence of TENORM leads to a twofold increase in radon activity concentration compared to the environmental background. A dosimetry campaign conducted in Crotone demonstrated excellent agreement between the model's predictions and actual measurements, suggesting that monitoring radon activity provides a practical means to indirectly assess whether and where TENORM was utilized during building construction.

A procedure for the containment of potential radiological risk systematically applied to sampling activities and site visits in areas lacking environmental knowledge allowed the discovery of eight sources of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${}^{\mathbf{226}}\mathbf{Ra}$</tex> buried under the road surface in an industrial area of the Calabrian territory. The ArpaCal (Calabrian Envinronmental Protection Agency) and its researchers routinely perform a field radiometric check by preliminarily observing the environmental radioactivity levels of the sites of interest. This operation can be codified as a mere activity of prevention of workers' risk: a potential radiological risk associated with workers of territorial and laboratory services who perform sampling activities in portions of territory where there is no information on the possible presence of hostile material and who are usually classified as workers belonging to the population and therefore not exposed. On a portion of about 30 square meters of bituminous road and falling within a larger industrial perimeter of about 10 hectares, eight capsules of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${}^{\mathbf{226}}\mathbf{Ra}$</tex> were found scattered and buried without metallic support, covered with river stones and bitumen in a good state of preservation. This work presents the complex activities of unearthing the sources, the evaluation of the dose for the workers involved in the discovery operations, the management of the found material, and the opportunity and effectiveness of a containment procedure of the risk for workers and the population.

Radon activity concentration measurements in air can be easily performed by using CR-39 detectors whose response is almost linear in the range of medium-low exposures. However, when the exposure values grow too much, a saturation phenomenon becomes relevant and some corrections have to be adopted even if they cannot always be very accurate and easy to apply. Therefore, a simple alternative method for determining the correct response curve of the CR-39 detectors, from low up to very high radon exposures, is showed. To verify its robustness and the general applicability, several certified measurements were carried out in a radon chamber at different levels of exposure. Moreover, two different types of commercially available radon analysis systems were used.

We investigate the nonlinear optical properties of natural topaz. For the first time, the observation of nonlinear phenomena related to multiphoton absorption effects, such as the up-conversion luminescence of the material defects, is reported in natural gems. In particular, we were able to detect the presence of the AlO4-related defects which are responsible for the change of the color of topaz as a consequence of irradiation with γ-rays as well as electrons and neutrons beams. Besides, the nonlinear spectral broadening of intense laser beams permits to spot of the presence of rare earth elements, such as Ytterbium and Neodymium, which are not found by means of standard characterization techniques of natural gems, e.g., those based on X-ray fluorescence, electron paramagnetic resonance, and linear optical fluorescence and absorbance measurements. In this sense, our results demonstrate that nonlinear optical effects induced luminescence measurements are a complementary, and previously unforeseen, technique for the characterization of the optical and physicochemical properties of natural gems. Finally, using intense infrared laser pulses allowed us to trigger extreme nonlinear effects, such as multiphoton ionization and conical emission. Our results will be of interest for the investigation of novel nonlinear optical effects in materials that are transparent in the whole visible spectral range and may give insights into the development of materials for nonlinear photonics.

Contamination of terrestrial and aquatic ecosystems by toxic industrial waste has become a major issue in many countries. Of particular concern is the reuse of toxic hazardous waste in construction materials. This paper examined for the first time the chemical and radiation ecotoxicity of site-specific Technological Enhanced Naturally Occurring Radioactive Materials (TENORM) residues from phosphate processing industry in soil environmental matrices through bioindicators. The area under investigation was the former industrial district of Crotone (Calabria, Italy), recently included within the Sites of National Interest (SIN), comprising the 42 Italian national priority contaminated sites. Major biological exposure pathways considered were absorption and bioaccumulation. The marine bacterium Vibrio fischeri and the freshwater crustacean Daphnia magna were employed as aquatic bioindicators, while for the soil ecosystem, the seeds of Sorghum saccharatum and Lepidium sativum were used. Selection of test species aimed at assessing the toxicity of wastes in soil as well as in freshwater or marine systems. Results indicated V. fischeri as the most sensitive of all the species tested (5.56 g/L), while D. magna was found to be affected at 94.27 g/L. An overall inhibition was observed in seedling growth as compared to control at the highest concentration of the pollutants (100 g/L), while seed germination was not adversely affected by the pollutant. At this preliminary level, data indicated a potential risk for biodiversity of the area. In fact, the measured toxicity thresholds, even if above 100 mg/L, are comparable to concentrations of the toxicants spread all over the territory of Crotone.

A new radiological risk containment procedure, developed to manage the radiological risk in potentially contaminated areas, is presented here. This new methodological approach, systematically employed in sampling and site inspection activities in unknown areas from an environmental point of view, allowed the discovery of eight 226Ra orphan sources buried under the road surface, in a good state of conservation, in an industrial area of the Calabrian territory, southern Italy, and they are reported here as a case study. For workers performing sampling activities in areas for which information regarding the possible presence of contaminated material is missing, an in situ radiometric check is usually carried out as a potential radiological risk prevention, by measuring the levels of environmental radioactivity. Other than this, the procedure described in this article includes, as novelty, a series of progressive operations never carried out before all together for outdoor activities: the assessment of the presence (if any) of hot spots by recording radiometric anomalies, outdoor gamma spectrometry measurements in order to identify the radionuclides generating those anomalies, the sources unearthing activities, the management of the material found and the application of a risk containment protocol.

The use of isotopic geochemistry for hydrogeological studies is growing internationally. The use of isotopic geochemistry methodologies on hydrogeological survey data, integrated with the use natural tracers, is helpful when defining the hydrogeological model of the aquifer. In particular, the use of radioisotope concentration measurements as natural tracers and the detection of the temperature, redox potential and dissolved oxygen in groundwater in the field provide information on underground water circulation, which is useful for identifying recharge areas and groundwater drainage. Variations in these parameters in the aquifer allow for information about its hydrodynamics to be obtained. The application of this method in a sample area showed how the uranium and radon concentrations, temperature, redox potential and dissolved oxygen vary in the different sectors of the aquifer, depending on water mobility. This information, integrated with the results of a hydrogeological survey of the static levels, distinguished the recharge and drainage areas of the aquifer and the preferential directions in terms of water flow and allowed for information on the mobility of the aquifer in the various sectors to be obtained. The method presented in this paper was tested in a larger hydrogeological study in the southern sector of the shallow aquifer of the S. Eufemia Lamezia plain (Calabria, Italy).

Radon exhalation from soil and ores is among the most dangerous risks for the public health care. The impact becomes even more powerful when technological enhanced naturally occurring radioactive materials (TENORM) are used for public and private building. Here, we built a down-scaled model (a 1.0 m × 1.0 m × 0.5 m parallelepiped) of a dwelling, whose construction materials contain TENORM harvested in a site in Crotone (Italy). We observed an increase of the radon activity in the model when TENORM residues are employed, reaching a value around 120 Bq/m3, i.e. up to three times higher than the typical values of Crotone indoor environment, which ranges around 40 Bq/m3. These results have then been compared to a real use case. The correspondence found between the values of radon activity concentration in the model and in the use case suggests that estimating the radon concentration is a useful method to target TENORM presence inside buildings.

Radon exhalation from soil and ores is among the most dangerous risks for the public health care. The impact becomes even more powerful when technological enhanced naturally occurring radioactive materials (TENORM) are used for public and private building. Here, we report the realization of a down-scaled model of a building, whose construction materials contain TENORM harvested in a site in Crotone (Italy). We observe an increase of the radon activity in the model when TENORM residues are employed. These results have then been compared to a real use case. The correspondence found between the values of radon activity concentration in the model and in the use case suggests that estimating the radon concentration is an useful method to target TENORM presence inside buildings.

In the present article, a case study is reported regarding an investigation carried out in order to assess radioactivity concentration, heavy metals pollution and mineralogy of a beach stretch extending from Soverato to Squillace municipalities of the Ionian coast of Calabria, South of Italy, a popular tourist destination, especially in summer. The analysis of radionuclides contents was performed by using a High Purity Germanium (HPGe) gamma-ray detector, in order to quantify the average specific activity of 226Ra, 232Th and 40K natural radionuclides and 137Cs anthropogenic radioisotope. The absorbed dose rate and the annual effective dose equivalent radiological hazard indices were also estimated. Furthermore, X-ray Fluorescence (XRF) spectrometry measurements were carried out for the quantitative elemental analysis of the sand, in order to investigate any possible chemical pollution by heavy metals. For this aim, different indices such as Enrichment Factor (EF), Geoaccumulation Index (Igeo), Contamination Factor (CF) and Pollution Load Index (PLI) were applied to estimate the level of toxicity imposed on the ecosystem by the detected heavy metals. Finally, in order to identify the crystalline mineral components of the investigated sand samples, X-ray Diffraction (XRD) and Micro-Raman Scattering (MRS) measurements were carried out.

Starting in 2010, the Regional Environmental Protection Agency of Calabria has promoted a campaign to measure the concentration of radon activity in indoor environments. This work presents the procedures and methods used to implement radon risk mitigation actions in living environments, in the territory of Calabria Region starting from the measurement of the concentration of activity. In particular, we have an experience that has achieved the goal with a remedial action capable of significantly reducing the levels of natural radioactivity and making them negligible for the purpose of assessing the risk of lung cancer. Actions to mitigate the concentration of radon gas activity have been proposed and implemented in a middle school in the Calabria Region where values ​​of around 1000 Bq/m3 have been recorded. If the rules of environmental accounting are applied to the life cycle of the intervention, while satisfying the principle of justification that governs radioprotection interventions, it is possible to carry out assessments in terms of environmental sustainability.

SUMMARY : ZINC FRACTIONATION AND AVAILABILITY BY DIFFERENTEXTRACTANTS IN SEWAGE SLUDGE-INCUBATED SOILS The final disposal of sewage sludge has become a cause of environmental concern.Because of its high content of both organic matter and plant nutrients, sewage sludge hasbeen used as fertilizer. However, it is important to know the fractions and bioavailability ofheavy metals in sludge-amended soils. In the case of zinc, one of the most abundant metalsin sewage sludge, knowledge on forms and plant availability are important to predict itsbehavior in soils. The present experiment was carried out to evaluate the Zn distributionacross different soil fractions after incubation with sewage sludge. In addition, Znavailability was evaluated by DTPA, EDTA, Mehlich-1, and Mehlich-3 extractants as wellas its relationship with Zn uptake by corn plants. Five sewage sludge doses (0; 40.5; 81;162; and 243 Mg ha -1 ) were added to two chemically and physically contrasting soil samples.After a 180 day-period incubation, sludge applications increased corn shoot dry weight,with no Zn toxicity symptoms in both soils. The EPA recommended Zn dose was saferegarding Zn contamination of soils and plants. The Zn content in several soil fractionsfollow the order: Residual > Organic matter > exchangeable > crystaline iron oxide >amorphous iron oxide. Mehlich-1 and Mehlich-3 extractants presented the highest Znrecovery, but all of them were effective to predict Zn availability.Index terms: heavy metals, biosolid, sequential extraction, chemical extractant.