Carla Roselli

Soil concentration, vertical distribution and inventory of plutonium, 241Am, 90Sr and 137Cs in the Marche Region of Central Italy.

Soil concentrations of 239+240Pu, 238Pu, 241Am, 90Sr, and 137Cs are investigated in the Marche Region of Central Italy. Mean values in uncultivated soils (0.721 +/- 0.456, 0.023 +/- 0.014, 0.241 +/- 0.165, 5.40 +/- 3.32, and 62.3 +/- 33.9 Bq kg(-1), respectively) are 3.5-8 times higher than the corresponding values in cultivated soils (0.147 +/- 0.054, 0.005 +/- 0.002, 0.047 +/- 0.021, 1.53 +/- 0.44, and 7.70 +/- 2.07 Bq kg(-1)). Radionuclide inventories and ratios are consistent with values reported by the United Nations Scientific Committee on the Effect of Atomic Radiation for this latitude (40-50 degrees N). This suggests that radiocontamination in this region is mainly due to atmospheric deposition of nuclear weapon test fallout. The vertical distribution of these radionuclides is also studied. The results show that, with the exception of 90Sr (68%), more than 90% of these radionuclides are contained in the first 20 cm of soil and that mobility follows the order 90Sr > 241Am > 239+240Pu, 238Pu > 137Cs.

210Po and 210Pb inhalation by cigarette smoking in Italy.

210Po and its precursor 210Pb in cigarette smoke contribute a significant radiation dose to the lungs of smokers. In this work, the concentration of 210Po was determined in 17 of the most frequently smoked cigarette brands in Italy. Samples of tobacco, fresh filters, ash, and post-smoking filters were analyzed; 210Po was determined by alpha spectrometry after its spontaneous deposition on a silver disk. To verify the radioactive equilibrium between 210Po and 210Pb, lead was determined in one tobacco sample by counting the beta activity of its decay product 210Bi with a gas flow proportional detector after separation. The results of the present study show 210Po concentrations ranged from 6.84 to 17.49 mBq per cigarette. Based on these results, smokers who smoke 20 cigarettes per day inhale, on average, 79.53 ± 28.65 mBq d−1 of 210Po and 210Pb each. The mean value of the annual committed effective dose for Italian smokers, calculated by applying the dose conversion factor for adults of 4.3 &mgr;Sv Bq−1 for 210Po and 5.6 &mgr;Sv Bq−1 for 210Pb, was estimated to be 124.8 and 162.6 &mgr;Sv y−1 for 210Po and 210Pb, respectively. The lung dose from inhalation of cigarette smoke is much higher than the lung dose from inhalation of atmospheric 210Po and 210Pb.

Natural and artificial radioactivity determination of some medicinal plants.

Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha ((238)U, (210)Po) and gamma ((214)Pb-Bi, (210)Pb, (40)K and (137)Cs) spectrometry. (238)U ranged between <0.1 and 7.32 Bq kg(dry)(-1); (210)Po between <0.1 and 30.3 Bq kg(dry)(-1); (214)Pb-(214)Bi between <0.3 and 16.6 Bq kg(dry)(-1); (210)Pb between <3 and 58.3 Bq kg(dry)(-1); (40)K between 66.2 and 3582.0 Bq kg(dry)(-1); (137)Cs between <0.3 and 10.7 Bq kg(dry)(-1). The percentage of (210)Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of (210)Po extraction resulted 20.7+/-7.5.

Radiation protection and radioactive scales in oil and gas production.

Low specific-activity scales consisting of alkaline earth metal carbonates and sulfates are often present in some gaseous and liquid hydrocarbon plants. These scales contain a certain concentration of radium, uranium, and thorium which can cause a risk of gamma irradiation and internal radiocontamination when they must be mechanically removed. The gamma dose rates and the 238U, 232Th, 226Ra concentrations were determined in sludges, scales, and waters of some gas and oil hydrocarbon plants located in Italy, Congo, and Tunisia. 238U and 232Th concentrations were were low. The isotopes 238U and 234U resulted in radioactive equilibrium, while 232Th and 228Th were not always equilibrium. A rough correlation was found between the gamma dose rate and the 226Ra concentration. Some considerations and conclusions about radiation protection problems are pointed out.

The importance of radiochemistry for the characterization of NORM and of environments contaminated by NORM

Naturally occuring radioactive materials (NORM) are present in the environment and they can be concentrated by technical activities, particularly those involving natural resources. This article describes radioanalytical problems arising in the accurate determination of natural radionuclides in NORM and in the environment contaminated by NORM. The solution of these problems is of particular importance since the results can be used to estimate the dose to workers and to the population. A special emphasis is given to the reliability of the radiochemical methods and procedures applied for the detection and measurement of alpha or beta emitters by radiometric or non-radiometric techniques.

Essential and toxic elements in seaweeds for human consumption

ABSTRACT Essential elements (K, Ca, P, S, Cl, Mn, Fe, Cu, Zn, Ni, Br, and I) and nonessential or toxic elements (Al, Ti, Si, Rb, Sr, As, Cd, Sn, and Pb) were determined by energy-dispersive polarized x-ray fluorescence spectrometry in 14 seaweeds purchased in local specialty stores in Italy and consumed by humans. The differences in elements between the algae species reached up to 2–4 orders of magnitude. Lithothamnium calcareum showed the highest levels of Ca, Al, Si, Fe, and Ti. Palmaria palmata showed the highest concentrations of K, Rb, and Cl. The highest content of S was in Chondrus crispus. Laminaria digitata contained the highest concentrations of total As, Cd, Sn, Br, and I. The highest concentration of Zn was in Chlorella pyrenoidosa. Ulva lactuca displayed the highest levels of Cu, Ni, Mn, and Pb. Iodine levels ranged from 3.4 in Chlorella pyrenoidosa to 7316 mg/kgdry in Laminaria digitata. The nutrimental importance of essential elements was assessed using nutritional requirements. The results showed that the consumption of algae might serve as an important source of the essential elements. Health risk due to the toxic elements present in seaweed was estimated using risk estimators. Total As, Cd, and Pb concentrations ranged from <1 to 67.6, to 7.2 and to 6.7 mg/kgdry respectively; therefore, their contribution to total elemental intake does not appear to pose any threat to the consumers, but the concentrations of these elements should be controlled to protect the consumer against potential adverse health risks.

Natural radionuclides in seafood from the central Adriatic Sea (Italy).

Activity concentrations of 210Po, 210Pb, and 40K were measured in different samples of marine organisms from the central Adriatic Sea. The marine organisms were purchased from the local consumer market during all four seasons of the year to evaluate the spatial and temporal distribution of the natural radioactivity. The concentration trend is the following: 40K > 210Po > 210Pb. 40K concentration ranged between 54.9 and 235.9 Bq kg−1 fresh weight, and the arithmetic mean of 210Pb concentration for all samples is <0.7 Bq kg−1 fresh weight. 210Po activity concentration ranged between 0.3 and 44.6 Bq kg−1 fresh weight; its arithmetic mean was 5.7 ± 7.2 Bq kg−1 fresh weight. Among the pelagic species, anchovy displayed the highest polonium concentration. The data obtained depend upon the type of marine organism and the period of sampling. Committed effective dose due to 210Po ingestion from marine food for individuals in the two different population groups was calculated to be 95.9 and 466.4 &mgr;Sv y−1, respectively.

Vertical profiles of 239,240Pu and 241Am in two sphagnum mosses of Italian peat

Abstract During the last two years the Urbino University and the Padua ICTIMA CNR collaborated on a special radioecological program having the aim to study the Pu and Am retention behaviour in Sphagnum peat in the Alps region (northern Italy). 239,240 Pu, 238 Pu and 241 Am were separated and determined by extraction chromatography, electroplating and alpha spectrometry; 242 Pu and 243 Am were used as the yield tracers. The paper summarizes the results dealing with the vertical profiles of the radionuclides in Sphagnum compactum and S. nemoreum . Several 1–2 cm high sections were obtained and dated by 210 Pb determination. Typical concentration peaks for Pu and Am were found at a depth corresponding to the early 1960s which is the period characterized by the maximum nuclear weapon tests.

Essential and Toxic Elements in Honeys From a Region of Central Italy

Levels of iron (Fe), manganese (Mn), chromium (Cr), copper (Cu), zinc (Zn), mercury (Hg), cadmium (Cd), and lead (Pb) in several types of honey produced in a region of Central Italy were determined by atomic absorption spectroscopy (AAS). The degree of humidity, sugar content, pH, free acidity, combined acidity (lactones), and total acidity were also measured. These elements were found to be present in honey in various proportions depending upon (1) the area foraged by bees, (2) flower type visited for collection of nectar, and (3) quality of water in the vicinity of the hive. Strong positive correlations occurred between Pb and Hg, Pb and Cd, Pb and Fe, Pb and Cr, Hg and Cd, and Hg and Fe. The honey products synthesized in Central Italy were of good quality, but not completely free of heavy metal contamination. Compared with established recommended daily intakes, heavy metals or trace element intoxication following honey consumption in Italy was found not to be a concern for human health.

210Po determination in urines of people living in Central Italy

This paper presents the results of the monitoring programme on the urines of people living in an area of Central Italy (near the Republic of S. Marino) to evaluate the background level of the 210Po excretion rate (mBq day(-1)) in this region. The volunteers were subdivided in five age classes and in every age class groups of males and females, cigarette smokers and non-smokers were taken into account. The results indicated that the 210Po excretion rate was widely distributed within each group of volunteers. The 210Po excretion rate was <30 mBq day(-1) for 93.2% of people. The obtained results are discussed and some conclusion, based upon the average values, was drawn.