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In the present work natural radioactivity was investigated in 27 samples of meat (fish, pork, chicken) collected in the period 2014–2016 from Galati, Braila and Vrancea counties, Romania. Level of gross alpha activity, gross beta activity and the concentrations of 210Po, 210Pb, 238U, 232Th, 226Ra, and 40K were determined. The values of the activity concentrations (fresh weight) in meat samples ranged in the intervals: 9–1632 mBq kg−1 (gross alpha), 31–133 Bq kg−1 (gross beta), 15–62 mBq kg−1 (210Po), 7–28 mBq kg−1 (210Pb), 9–58 mBq kg−1 (238U), 5–19 mBq kg−1 (232Th), 18–126 Bq kg−1 (40K), 0.7–5.7 Bq kg−1 (226Ra). Although the highest effective dose per kg was calculated for fish samples (2.4 ± 0.3 μSv kg−1), the highest annual effective dose (47.5 ± 6.6 μSv year−1) has been found in case of pork meat consumption.

Background This paper aims to investigate the correlations between the concentrations of nine heavy metals in moss and atmospheric deposition within ecological land classes covering Europe. Additionally, it is examined to what extent the statistical relations are affected by the land use around the moss sampling sites. Based on moss data collected in 2010/2011 throughout Europe and data on total atmospheric deposition modelled by two chemical transport models (EMEP MSC-E, LOTOS-EUROS), correlation coefficients between concentrations of heavy metals in moss and in modelled atmospheric deposition were specified for spatial subsamples defined by ecological land classes of Europe (ELCE) as a spatial reference system. Linear discriminant analysis (LDA) and logistic regression (LR) were then used to separate moss sampling sites regarding their contribution to the strength of correlation considering the areal percentage of urban, agricultural and forestry land use around the sampling location. After verification LDA models by LR, LDA models were used to transform spatial information on the land use to maps of potential correlation levels, applicable for future network planning in the European Moss Survey. Results Correlations between concentrations of heavy metals in moss and in modelled atmospheric deposition were found to be specific for elements and ELCE units. Land use around the sampling sites mainly influences the correlation level. Small radiuses around the sampling sites examined (5 km) are more relevant for Cd, Cu, Ni, and Zn, while the areal percentage of urban and agricultural land use within large radiuses (75–100 km) is more relevant for As, Cr, Hg, Pb, and V. Most valid LDA models pattern with error rates of

The aim of this work was to assess the levels of copper and zinc in fish from the main freshwater ecosystems of Moldova, in relation with species, habitat, age, sex, season, and development stage. Fish from Cyprinidae and Percidae families (Cyprinus carpio, Carassius auratus gibelio, Rutilus rutilus heckeli, Abramis brama, Aristichthys nobilis, Hypophtalmichthys molitrix, Sander lucioperca) were collected from Prut and Dniester rivers, Cuciurgan, Dubasari, and Costesti-Stanca reservoirs, and ponds of farms in the Dniester delta. The Cu and Zn content of fish tissues (skeletal muscles, liver, gonads, gills, skin, and scales) was determined by flame atomic absorption spectrophotometer AAS-3, of water by graphite furnace HGA 900 of AAnalist 400. The level of heavy metals accumulation in muscles of immature fish follows their dynamics in water. The highest concentration of zinc was registered in the gonads of mature fish, and of copper—in the liver. The lowest Cu and Zn contents were recorded in the muscles and are in the United Nations Food and Agriculture Organization safety-permissible levels for human consumption. Cu and Zn contents in muscles of fish depend on specimen age. Their level in fish gonads was sharply increasing during pre-spawning period. During the early developmental stages, the metal concentration in fish eggs and larvae varies within wide limits, but the accumulation pattern is similar in the investigated species. The fish represent one of the most indicative factors for the estimation of trace metals pollution in freshwater systems and this is important not only for monitoring purposes, but also for the fish culture ones.

The nuclear and spectral interferences in the 14 MeV neutron activation analysis (NAA) of gold from Romanian auriferous alluvial sands, concentrates and rocks have been studied and the optimum of activation, cooling and measuring times was determined for a maximum peak-to-background ratio for gold. The contribution of the nuclear interfering elements in the samples, Hg and Pt, to the concentration of gold has been calculated and, concluded that the nuclear reactions 197Au(n,2n)196Au, 197Au(n,2n)196mAu and 197Au(n,n')197mAu can be used for gold determination, with minimal errors. Using the nuclear reactions 197Au(n,n')197mAu and 197Au(n,2n)196Au the spectral interferences are minimal and are due to Rb, Ti and V for a short irradiation and to Se for a long one. Two methods of fast gold determination were proposed for auriferous alluvial sands and rocks in the range of 20-2500 ppm, under the optimum conditions established so that the systematic errors of analysis due to the gold accompanying elements can be considerably diminished. For measuring the induced gamma-radioactivity in the samples either a short irradiation (25 seconds) with a NaI(Tl) detector or a long irradiation (3000 seconds) with a Ge(Li) detector were used.

Instrumental neutron activation analysis (INAA) was applied to investigated a total of 16 samples of raw materials, intermediate and final products involved in metallurgical processes in Romanian Iron and Stell works Sidex Galatzy: iron ores and pellets from different regions of the world, cast iron, slag and steels. A series of chemical elements was determined in the analyzed samples: Al, As, Ce, Co, Cr, Fe, La, Mn, Na, Sc, Sm, V, W. A qualitative discussion regarding the passing of from elements with different chemical affinity for oxygen compared to that of iron, from the raw materials to slag or to finite products is presented.