Radionuclides in some spring mineral waters in Serbia

Radiochemical analyses ofsome natural mineral bottled waters from different location in Serbia were investigated. Concentrations of all present naturally occurring radionuclides, 238 U, 234U, 232Th, 230Th, 228Th, 228Ra and 226Ra and 234U/238 U, 226Ra/230Th, 228Th /232Th, and 228 Ra/228 Th activity ratios were calculated and discussed. Uranium series disequilibria in the hydrosphere occur due to geochemical differentiation processes resulting with different mobility of the radionuclides from the same series. We have investigated radioactive disequilibrium in the spring waters Crni Guber, Čibutkovica and Studenica, originated from metamorphic rock area. High content of radium isotopes (226Ra, 228Ra) in analysed natural spring waters indicates contribution from other non-water sources, probably environmental sediment.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

Justification, Optimization and Reference Levels in Existing Exposure Situations

U radu su razmatrani zahtevi za upravljanje situacijama postojećeg izlaganja a naročito primena principa opravdanosti i optimizacije zaštite, odnosno uvođenje referentnih nivoa za uspostavljanje kontrole nad ovim situacijama. Diskutovane su preporuke iz standarda MAAE i regulative Evropske unije, koje su zasnovane na nalazima Međunarodnog komiteta za zaštitu od zračenja, kao i relevantne odredbe propisa Republike Srbije. Istaknut je značaj donošenja dugoročne Strategije upravljanja situacijama postojećeg izlaganja, sa odgovarajućim akcionim planovima za implementaciju.The requirements for managing situations of existing exposure, and especially the implementation of the principles of justification and optimization of protection, and introduction of reference levels for establishing control over these situations have been discussed in the paper. Reccomendations given by the IAEA standards and EU regulations, which are based on the findings of the International Committee on Radiation Protection were considered as well as certain provisions of the regulations of the Republic of Serbia. The need and importance of adopting a long-term strategy for managing existing exposure situations, with appropriate action plans for implementation, was highlighted.XXXII Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, 4-6. oktobar 2023; Budva, Crna GoraProceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/11602

Migration of depleted uranium contamination through the soil

Military use of ammunition with depleted uranium at South Serbia, caused contamination of the environment. Surface soil and soil profile around projectile with depleted uranium were analyzed three years later by high resolution alpha/gamma spectrometry. It was found that activity levels in the soil layer next to the penetrator changes to 1% of initial value at 15 cm distance. This value is about double background uranium level of the soil at the Bratoselce location.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

Annual variations of fine respirable aerosol fraction in urban residential areas

Fine particlulate matter fraction (PM 2.5) of urban aerosol collected daily for one year with 3/7 frequency at urban background locations in Banja Luka (BL) and Belgrade (BG) had been analyzed and discussed. Mass concentrations of aerosol deposit were determined by standard gravimetric procedure and concentrations of elements with antropogenic and crustal origin have been obtained by application of nuclear analytical techniques (PIXE, XRF). Resulted descriptive statistic parameters have shown that PM 2.5 annual limit value 25 μgm-3was exceeded during the heating period in both investigated regions but with significantly higher values in Banja Luka due to different heating type and structure and local traffic characteristics. Observed concentrations of S and K are high and based on other metals concentration some industrial influences have been indicated.Physical chemistry 2016 : 13th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-30 September 201

The radiological risk assesment methodology applied on sands from public beaches

The radiological risk of public exposure to terrestrial radiation in the sand beaches is assessed through the total absorbed gamma dose rate in air and annual effective dose outdoors determination according to international recommendations. Corresponding hazards due to sand use as a building material has been estimated by gamma irradiation hazard indices, based on the data of natural radionuclides contents in sands from public seaside and riverbank beaches (Ulcinj, Belgrade- Danube) obtained in this study, using spectrometry of gamma radiation.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200

Heavy metal content of pm10 and pm2.5 within urban area of Belgrade

An assessment of air quality of Belgrade was performed by determining the trace element content in airborne PM10 and PM2.5 in two years period. Samples were collected at two locations in a heavy polluted area. The concentrations of Al, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn were determined with AAS. Results indicated that the ambient concentration of Zn in the PM10 and PM2.5 was the highest (1389.18 and 1998.00 ng m-3 respectively). Also, the highest enrichment factor (EF) value was obtained for Zn, folowing with high EF for Cd and Pb in PM10, reflecting the importance of anthropogenic inputs. The limit values of toxic trace elements from WHO and EC Air quality guidelines were not exceeded except for Ni.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

Uticaj dezificijensa na različite sojeve Listeria monocytogenes

The objective of this work was to determine which of the examined disinfectants represents the agent of choice for isolates of L monocytogenes originating from foodstuffs of animal origin and if there are differences regarding sensitivity associated with specific serotypes. Disinfectant A (sodium hypochlorite + phosphates + alkali) did not exhibit a listericidal effect on any examined serotype, while disinfectants B (10 % hydrochloride of 1- dodecyl-1.4.7- triazooctane - 8- carbonic) and C (acidic iodoform with tenside- iodine complex)) exhibited a listericidal effect against most strains. Desinfectant B had the greatest effect at the highest working concentration (2 %) with a very significant difference (p lt 0.01) in comparison with the listericidal effect of disinfectant C. Analysis of the sensitivity of different serotypes of L monocytogenes showed that, despite evident higher or lower sensitivity to disinfectant B, the antigenic structure (seroype) was not related to the sensitivity of the examined strains. However, with disinfectant C, the greatest listericidal effect was exhibited on serotypes 3a and 112b, while it was smaller for other serotypes of L monocytogenes. Statistically very significant differences (p lt 0.01) and significant differences (p lt 0.05) were detected between the mean inhibition zones of most serotypes of L monocytogents. Therefore, the sensitivity of different strains of L. monocytogenes originating from foodstuffs of animal origin to disinfectants can be related to the antigenic structure, actually the serotype (C) or not (disinfectant B).Cilj ovog rada je da odgovori na dva vrlo značajna pitanja: prvo, koji od ispitivanih dezinficijenasa ispoljava najbolji dezinfekcioni efekat na sojeve Listeria monocytogenes, poreklom iz namirnica animalnog porekla i drugo, da li u pogledu osetljivosti L monocytogenes prema ispitivanim dezinficijensima postoje razlike uslovljene serotipskom pripadnošću. Dezificijens A (natrijum hypochlorit+phosphati+alkalija) nije ispoljio listericidni efekat ni prema jednom ispitivanom serotipu, dok su dezificijensi B (10% hydrochloride 1-dodecil-1,4,7-triazooctan-8-carbonska kiselina) i C (kiseli iodoform satensid-iodnim kompleksom) ispoljili listericidni efekat prema većem broju sojeva. Dezificijens B ispoljio je najviši baktericidni efekat pri najvišoj radnoj koncentraciji sa statistički vrlo značajnom razlikom (p lt 0,01) u odnosu na listericidni efekat dezificijensa C. Analizom rezultata osetljivosti različitih sojeva Listeria monocytogenes utvrđeno je da i pored evidentne ispoljene osetljivosti listerija prema dezificijensu B, antigensa struktura odnosno, serotip nema većeg značaja u pogledu osetljivosti ispitivanih sojeva. Medutim dezificijens C, najveći listericidni efekat ispoljio je prema listerijama serotipa 3a i 1 /2b, dok je prema ostalim serotipovima bio manji. Između aritmetičkih sredina zona inhibicije većine serotipova, utvrđene su statistički vrlo značajne razlike (p lt 0,01), odnosno značajne razlike (p lt 0,05). Na osnovu dobijenih rezultata može se zaključiti da je osetljivost različitih sojeva L monocytogenes poreklom iz namirnica animalnog porekla bila ispoljena prema dezinficijensu B, kao i da osetljivost listerija prema ispitivanim dezinficijensima zavisi od njihove antigenske strukture odnosno serotipske pripadnosti

Health Risk Assessment of Particulate Matter Emissions from Natural Gas and Fuel Oil Heating Plants Using Dispersion Modelling

A significant proportion of homes and apartments in Serbia are still reliant on central heating systems during winter months, with about fifty heating plants in operation. Common fuels used in these plants primarily include fossil fuels such as coal, fuel oil, and natural gas. Some of these fuels have a high sulfur content, leading to an increased concentration of sulfur dioxide and particulate matter in the atmosphere (Todorović et al, 2020; Todorović et al, 2021). This study compares and evaluates the environmental impact of the two heating boilers at the Valjevo city (Serbia) heating plant. The AERMOD air dispersion model was used for estimating the concentrations of the various pollutants (Kakosimos et al, 2011; Mokhtar et al, 2014; Shaikh et al, 2020). Onsite emission data were gathered separately for the two heating boilers at the facility fuelled by natural gas and fuel oil, respectively. A combination of topographical and historical meteorological data were used to set up a receptor grid that was exposed to the gas emission in a radius of 10 km. The environmental impact from the fuel oil boiler was shown to be significantly higher than that caused by the natural gas-fuelled boiler. The resulting distribution of pollutant gases and particles showed that the concentration gradient is less inclined towards the city centre and instead spreads eastwards into the surrounding villages. The data were used to evaluate carcinogenic and non-carcinogenic health risks. It was found that the health risk was acceptable for different averaging periods. However, further study is still required in order to properly assess the cumulative health risk generated by other surrounding industries

Discovery of uranium mineralizations in the rhyolite-granite complex in the Jabal Eghei area of southern Libya

During investigation of the Jabal Eghei area in southern Libya and the production of geological maps at a scale of 1:250 000 (Tibesti sector, sheet Wadi Eghei NF 34-1 and NF 34-2), regional prospecting for mineral raw materials was performed. Radiometric survey of observed targets at the sites indicated two significant uranium mineralizations in rhyolites, and some smaller ones in granites that are in close contact with rhyolites. Rhyolites are located in the central part of the investigated region. They cut through granite rocks. The first mineralization is in the central part of the rhyolite region, which is mostly composed of silificated rhyolites. The second one was discovered near the granite-rhyolite contact zone, characterized by the presence of silicified breccia rocks. These findings were confirmed by laboratory measurements of more than seventy samples collected in the area, using high resolution gamma-ray spectrometry. The concentrations of uranium in these mineralizations were found to range from approx. 50 mg kg-1 to more than 600 mg kg-1. The latter value is about 240 times above the Earth’s average. Besides uranium, these measurements have also given concentrations of thorium and potassium. Additional geochemical analysis was performed on samples taken from locations where uranium anomalies were discovered using ICP-MS technique, in which concentrations of more than forty elements were determined. Uranium mineralizations are accompained by increased contents of silver (up to 17 times), arsenic (up to 8 times), molybdenum (up to 50 times), mercury (up to 9 times), and lead (up to 14 times), in regard to the Clark’s values. These results warrant a continued investigation of this region because of potential interest in the discovery of nuclear mineral raw materials