Branko Petrinec - Academia.edu (original) (raw)

Papers by Branko Petrinec

Journal of Environmental Science and Health, Part B, 2007

Systematic investigations of 137 Cs and 134 Cs activity concentrations in potatoes (Solanum tuber... more Systematic investigations of 137 Cs and 134 Cs activity concentrations in potatoes (Solanum tuberosum) for the post-Chernobyl period (1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005) in the Republic of Croatia are summarized. The correlation between 137 Cs activity concentrations in fallout and potatoes, has been found to be very good, the correlation coefficient being r 2 =0.88 with P(t) < 0.001 for 18 degrees of freedom. As the radiocaesium levels in potatoes decreased exponentially, the mean residence time of 137 Cs in potatoes was estimated by fitting the measured activity concentrations to the exponential curve. The mean residence time was found to be 6.8 ± 1.1 years, the standard deviation being estimated by the Monte Carlo simulations.

Radiation Protection Dosimetry, 2013

Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sedi... more Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sediment samples in the period from 2007 to 2011. The sampling areas were coastal waters of Slovenia, Croatia and Albania, together with the deepest part of the Adriatic in South Adriatic Pit and Otranto strait. Sampling locations were chosen to take into account all major geological and geographical features of this part of the Adriatic Sea and possible coastal influences. After initial sample preparation steps, samples were measured by gamma-ray spectrometry. In the seawater 40 K activity concentrations were in the range from 6063 to 10519 Bq m 23 , 137 Cs from 1.6 to 3.8 Bq m 23 , 226 Ra from 23 to 31 Bq m 23 , 228 Ra from 1 to 25 Bq m 23 and 238 U from 64 to 490 Bq m 23 . The results of sediment samples showed that 40 K was in the range from 87 to 593 Bq kg 21 , 137 Cs from 0.8 to 7.3 Bq kg 21 , 226 Ra from 18 to 35 Bq kg 21 , 228 Ra from 4 to 29 Bq kg 21 and 238 U from 14 to 120 Bq kg 21 . In addition, the ERICA Assessment Tool was used for the assessment of dose rates for reference marine organisms using the activity concentrations of the determined radionuclides in seawater. The assessment showed that for the most of the organisms, the dose rates were within the background levels, indicating that the determined values for seawater does not pose a significant risk for the most of marine biota. In the study, the results are critically discussed and compared with other similar studies worldwide. Generally, the activity concentrations of the examined radionuclides did not differ from those reported for the rest of the Mediterranean Sea.

Archives of Industrial Hygiene and Toxicology, 2000

This article brings the results of a method for quality assurance in gamma-ray spectrometry of se... more This article brings the results of a method for quality assurance in gamma-ray spectrometry of seabed sediments. Sediments were collected in selected locations of the South and Middle Adriatic Sea using grab and corer tools. Using our own experimental design, we determined the self-attenuation factors of selected samples. The article also discusses sources of uncertainty in gamma-ray spectrometry, which is another important issue in quality assurance. Together with self-attenuation correction sources of uncertainty are used to calculate the activity concentration for a given sample. The presented procedure demonstrates how a gamma-ray spectrometry experiment should be approached in order to properly account for errors and uncertainties specifi c to a particular sample.

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4±0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adriatic ...

Radiation Protection Dosimetry, 2012

Investigations in the post-Chernobyl period ) of radiocaesium activity concentrations in Adriatic... more Investigations in the post-Chernobyl period ) of radiocaesium activity concentrations in Adriatic pilchards are presented. Compared with pre-Chernobyl period, the Chernobyl nuclear accident caused increase of 137 Cs activity concentrations in pilchards. By fitting the measured 137 Cs activity concentrations to the theoretical curve was estimated to be 1.5+ + + + +0.4 y for 1986-90 and 5.8+ + + + +0.4 y for 1991-2009 and the bimodal behaviour for the ecological half-life of 137 Cs in pilchards has been observed. Estimated annual effective doses received by 134 Cs and 137 Cs intake due to consumption for an adult member of Croatian population are small. Collective dose for the 1986-2009 period was 4.910.3 person-Sv. The observed 134 Cs/ 137 Cs activity ratio in pilchards was similar to the ratio that has been found in other environmental samples.

Environmental Monitoring and Assessment, 2009

The long-term behaviour of l37Cs activity concentrations in air and fallout has been studied in t... more The long-term behaviour of l37Cs activity concentrations in air and fallout has been studied in the city of Zagreb for the post-Chernobyl period as a paft of an extended monitoring program of radioactive contamination of human environment in Croatia. Annual mean l37Cs activity concentrations in air and annual total deposition fluxes (wet plus dry) decreased from 2.8x10'-4 Bq m 3 in September 1986 to 3.0x 10-6 Bq rn-t in last quarler of 2006 and from 6,410 Bq m-' year-t in 1986 to 2 Bq m-2 year"-' in 2006 respectively. By fitting the measured l37Cs activity concentrations to the theoretical curve the ecological half-lives of l37Cs in air and fallout were estimated with respective values of 0.46 and 0.54 years for immediate post-Chemobyl period, increasing to 5.52 and 3.97 years aftetwards. Using the data on '37Cs activity concentrations in air and fallout total caesium deposition velocity of (3.34+ 3.13)x i0-2 ms-l was estimated with median value being 2.13 x 10-2 ms-r. Such relatively high r37Cs deposition velocities compared with pre-Chernobyl ones, are characteristic for the post-Chemobyl period and, according to Stokes' settling law, indicate that the diameters of aerosol particles associated with l37Cs originated from the Chernobyl accident are pretty large, i.e. >1 pm. l3'lcs/r37Cs activity ratio in fallout and in air has been found to be similar to the theoreticaily predicted values, initial value being about 0.5 and decreasing according to differential radioactive decay. The similar ratio has been observed in most of the other environmental samples.

Geologia Croatica, 2014

Geochemical analysis and trace element distribution were performed on the marine sediments from s... more Geochemical analysis and trace element distribution were performed on the marine sediments from short cores (30 to 50 cm) from the Middle (Jabuka and Palagruža pits, depth 230 m and 170 m, respectively) and South Adriatic Sea (depth 1030 m) and the Albanian offshore (50 m depth). The distribution of trace elements (As, Co, Cd, Cu Cr, Ni, Zn, Hg, and Pb) and major elements (Al, Ca and Mn) and mineralogy in the sediments is presented. Sediments are highly heterogeneous and consist of carbonate and detrital aluminosilicate minerals. The main mineral phase is calcite, followed by quartz, feldspars, micas and clay minerals (smectite, chlorite, illite and kaolinite). The cores were dated using 137 Cs. The cores from the South Adriatic Pit and Palagruža Sill gave estimated sedimentation rates of 1.8 mm y -1 and 3.1 mm y -1 in Jabuka Pit. Distributions of Ni and Cr showed that they can be used as tracers of sediment provenance along the southern part of the Eastern Adriatic Current. Calculated enrichment factors for Pb, Cd and Hg are highest in the top 2 cm of the cores. Mercury shows the highest degree of enrichment in 0-2 cm sediment intervals (the highest in the Albania core). Generally the estimated surface enrichment follows the order: Hg>Pb>Cd. No enrichment was found for Zn, Ni and Cr.

Quaternary Geochronology, 2013

Measurement of 226 Ra activity concentrations is often used to estimate supported levels of 210 P... more Measurement of 226 Ra activity concentrations is often used to estimate supported levels of 210 Pb for purposes of geochronology. However, the implicit assumption that supported 210 Pb and 226 Ra are in secular radioactive equilibrium may not always be true because of the migration of an intermediate product, gaseous 222 Rn. As a consequence, supported 210 Pb activity concentration might be lower than the measured 226 Ra value, which was the case in a core collected from the South Adriatic Pit. Here we present a new approach to improve the determination of supported 210 Pb, which is based on correction of 226 Ra activity concentrations using the average ( 210 Pb/ 226 Ra) activity ratio in deeper sediment layers. Using this approach, sedimentation rates for the South Adriatic Pit with a constant rate of supply model and a constant initial concentration model were 0.054 g/cm 2 /a and 0.070 g/cm 2 /a, respectively.

This article brings the results of a method for quality assurance in gamma-ray spectrometry of se... more This article brings the results of a method for quality assurance in gamma-ray spectrometry of seabed sediments. Sediments were collected in selected locations of the South and Middle Adriatic Sea using grab and corer tools. Using our own experimental design, we determined the self-attenuation factors of selected samples. The article also discusses sources of uncertainty in gamma-ray spectrometry, which is another important issue in quality assurance. Together with self-attenuation correction sources of uncertainty are used to calculate the activity concentration for a given sample. The presented procedure demonstrates how a gamma-ray spectrometry experiment should be approached in order to properly account for errors and uncertainties specifi c to a particular sample.

Arhiv za higijenu rada i toksikologiju, 2006

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4 +/- 0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adria...

Radiation Protection Dosimetry, 2010

Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric... more Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric measurements, both in situ and in laboratory, as well as radon measurements in the seawater were performed. Activity concentrations and the associated dose rates due to naturally occurring 232 Th, 238 U and 40 K radioisotopes were determined. Dose rates calculated from in situ gamma spectrometry are in correlation with dose rates calculated from activity concentrations measured in collected samples of pebbles and rocks. In situ gamma ray spectrometry in the seawater has been performed, showing activity concentration of 220 and 240 Bq m 23 for 214 Bi and 214 Pb, respectively due to the presence of magmatic rocks in the seabed. The radium equivalent activity varied from 13 to 53 Bq kg 21 . These values are lower than the limit values, indicating that the radiation hazard is not significant. The highest mean activity concentrations of naturally occurring radionuclides in rock samples collected were found on the islands of magmatic origin.

Radiation Protection Dosimetry, 2012

137 Cs activity concentrations were studied in the sediment profiles collected at five locations ... more 137 Cs activity concentrations were studied in the sediment profiles collected at five locations in the Middle and South Adriatic. In the sediment profiles collected from the South Adriatic Pit, the deepest part of the Adriatic Sea, two 137 Cs peaks were identified. The peak in the deeper layer was attributed to the period of intensive atmospheric nuclear weapon tests (early 1960s), and the other to the Chernobyl nuclear accident (1986). Those peaks could be used to estimate sedimentation rates by relating them to the respective time periods. Grain-size analysis showed no changes in vertical distribution through the depth of the sediment profile, and these results indicate uniform sedimentation, as is expected in deeper marine environments. It was not possible to identify respective peaks on more shallow locations due to disturbance of the seabed either by trawlers (locations Palagruža and Jabuka) or by river sediment (location Albania). The highest sedimentation rates were found in Albania (∼4 mm y 21 ) and Jabuka (3.1 mm y 21 ). For Palagruža, the sedimentation rate was estimated to be 1.8 mm y 21 , similar to the South Adriatic Pit where the sedimentation rate was estimated to be 1.8+ + + + +0.5 mm y 21 . Low sedimentation rates found for the Middle and South Adriatic Sea are consistent with previously reported results for the rest of the Mediterranean.

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4±0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adriatic ...

Arhiv za higijenu rada i toksikologiju, 2015

Phosphogypsum (PG) is a waste product (residue) from the production of phosphoric acid characteri... more Phosphogypsum (PG) is a waste product (residue) from the production of phosphoric acid characterized by technologically enhanced natural radioactivity. Croatia's largest PG deposition site is situated at the edge of Lonjsko Polje Nature Park, a sensitive ecosystem possibly endangered by PG particles. This field study investigates two aspects relevant for the general radiological impact of PG: risk assessment for the environment and risk assessment for occupationally exposed workers and local inhabitants. Activity concentrations of natural radionuclides (238U, 235U, 232Th, 226Ra, 210Pb, and 40K) were measured in the PG (at the deposition site), soil, and grass samples (in the vicinity of the site). The ERICA Assessment Tool was used to estimate the radiological impact of PG particles on non-human biota of the Lonjsko Polje Nature Park. The average annual effective dose for occupationally exposed workers was 0.4 mSv which was within the worldwide range.

Arhiv za higijenu rada i toksikologiju, 2006

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4 +/- 0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adria...

Geochemical analysis and trace element distribution were performed on the marine sediments from s... more Geochemical analysis and trace element distribution were performed on the marine sediments from short cores (30 to 50 cm) from the Middle (Jabuka and Palagruža pits, depth 230 m and 170 m, respectively) and South Adriatic Sea (depth 1030 m) and the Albanian offshore (50 m depth). The distribution of trace elements (As, Co, Cd, Cu Cr, Ni, Zn, Hg, and Pb) and major elements (Al, Ca and Mn) and mineralogy in the sediments is presented. Sediments are highly heterogeneous and consist of carbonate and detrital aluminosilicate minerals. The main mineral phase is calcite, followed by quartz, feldspars, micas and clay minerals (smectite, chlorite, illite and kaolinite). The cores were dated using 137 Cs. The cores from the South Adriatic Pit and Palagruža Sill gave estimated sedimentation rates of 1.8 mm y -1 and 3.1 mm y -1 in Jabuka Pit. Distributions of Ni and Cr showed that they can be used as tracers of sediment provenance along the southern part of the Eastern Adriatic Current. Calculated enrichment factors for Pb, Cd and Hg are highest in the top 2 cm of the cores. Mercury shows the highest degree of enrichment in 0-2 cm sediment intervals (the highest in the Albania core). Generally the estimated surface enrichment follows the order: Hg>Pb>Cd. No enrichment was found for Zn, Ni and Cr.

Radiation Protection Dosimetry, 2014

Long-term indoor radon measurements performed by LR 115 track etched detectors in Croatian homes ... more Long-term indoor radon measurements performed by LR 115 track etched detectors in Croatian homes during 2003-04 showed that the arithmetic means of radon concentrations in Lika-Senj and the southern part of Karlovac counties were three times higher (198 Bq m 23 ) than in houses at national level (68 Bq m 23 ). Recently, indoor radon measurements in randomly selected houses were investigated. The obtained values in these new measurements have confirmed the values obtained 10 y ago (the average radon value in 225 investigated houses in this area is 223 Bq m 23 ). Radon concentrations in soil gas were measured in September and October 2012 and 2013 with the AlphaGUARD measuring system. Areas with both elevated indoor radon levels and radon in soil gas were identified (some micro locations in Korenica, Ličko Lešće, Generalski Stol, Slunj and Ogulin) and visually presented in the form of maps using the inverse distance weighting approach.

Radiation Protection Dosimetry, 2009

Thermal waters are known as valuable natural resources of a country. They contain certain degree ... more Thermal waters are known as valuable natural resources of a country. They contain certain degree of natural radioactivity attributable to the elements of the uranium and thorium natural decay series. Among these elements, the most radiotoxic and the most important is radium that exists in several isotopic forms ( 226 Ra and 228 Ra). The focus of attention was the content of radium in samples of thermal and mineral spring water from several spas in Croatia. These waters are mainly used for medical, bathing and recreational purposes, and some of them are used for drinking. Measured activity concentrations of 226 Ra ranged from 87 to 6200 mBq l 21 which, in some springs, exceed the maximal permissible level of 1 Bq l 21 for drinking water. Measured activity concentrations of 228 Ra ranged from 23 to 3480 mBq l 21 . The study showed that radium content for the investigated thermal and mineral waters is below the levels at which negative consequences would arise due to ingestion.

Radiation Protection Dosimetry, 2013

Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sedi... more Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sediment samples in the period from 2007 to 2011. The sampling areas were coastal waters of Slovenia, Croatia and Albania, together with the deepest part of the Adriatic in South Adriatic Pit and Otranto strait. Sampling locations were chosen to take into account all major geological and geographical features of this part of the Adriatic Sea and possible coastal influences. After initial sample preparation steps, samples were measured by gamma-ray spectrometry. In the seawater 40 K activity concentrations were in the range from 6063 to 10519 Bq m 23 , 137 Cs from 1.6 to 3.8 Bq m 23 , 226 Ra from 23 to 31 Bq m 23 , 228 Ra from 1 to 25 Bq m 23 and 238 U from 64 to 490 Bq m 23 . The results of sediment samples showed that 40 K was in the range from 87 to 593 Bq kg 21 , 137 Cs from 0.8 to 7.3 Bq kg 21 , 226 Ra from 18 to 35 Bq kg 21 , 228 Ra from 4 to 29 Bq kg 21 and 238 U from 14 to 120 Bq kg 21 . In addition, the ERICA Assessment Tool was used for the assessment of dose rates for reference marine organisms using the activity concentrations of the determined radionuclides in seawater. The assessment showed that for the most of the organisms, the dose rates were within the background levels, indicating that the determined values for seawater does not pose a significant risk for the most of marine biota. In the study, the results are critically discussed and compared with other similar studies worldwide. Generally, the activity concentrations of the examined radionuclides did not differ from those reported for the rest of the Mediterranean Sea.

Radiation Protection Dosimetry, 2010

Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric... more Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric measurements, both in situ and in laboratory, as well as radon measurements in the seawater were performed. Activity concentrations and the associated dose rates due to naturally occurring 232 Th, 238 U and 40 K radioisotopes were determined. Dose rates calculated from in situ gamma spectrometry are in correlation with dose rates calculated from activity concentrations measured in collected samples of pebbles and rocks. In situ gamma ray spectrometry in the seawater has been performed, showing activity concentration of 220 and 240 Bq m 23 for 214 Bi and 214 Pb, respectively due to the presence of magmatic rocks in the seabed. The radium equivalent activity varied from 13 to 53 Bq kg 21 . These values are lower than the limit values, indicating that the radiation hazard is not significant. The highest mean activity concentrations of naturally occurring radionuclides in rock samples collected were found on the islands of magmatic origin.

Journal of Environmental Science and Health, Part B, 2007

Systematic investigations of 137 Cs and 134 Cs activity concentrations in potatoes (Solanum tuber... more Systematic investigations of 137 Cs and 134 Cs activity concentrations in potatoes (Solanum tuberosum) for the post-Chernobyl period (1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005) in the Republic of Croatia are summarized. The correlation between 137 Cs activity concentrations in fallout and potatoes, has been found to be very good, the correlation coefficient being r 2 =0.88 with P(t) < 0.001 for 18 degrees of freedom. As the radiocaesium levels in potatoes decreased exponentially, the mean residence time of 137 Cs in potatoes was estimated by fitting the measured activity concentrations to the exponential curve. The mean residence time was found to be 6.8 ± 1.1 years, the standard deviation being estimated by the Monte Carlo simulations.

Radiation Protection Dosimetry, 2013

Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sedi... more Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sediment samples in the period from 2007 to 2011. The sampling areas were coastal waters of Slovenia, Croatia and Albania, together with the deepest part of the Adriatic in South Adriatic Pit and Otranto strait. Sampling locations were chosen to take into account all major geological and geographical features of this part of the Adriatic Sea and possible coastal influences. After initial sample preparation steps, samples were measured by gamma-ray spectrometry. In the seawater 40 K activity concentrations were in the range from 6063 to 10519 Bq m 23 , 137 Cs from 1.6 to 3.8 Bq m 23 , 226 Ra from 23 to 31 Bq m 23 , 228 Ra from 1 to 25 Bq m 23 and 238 U from 64 to 490 Bq m 23 . The results of sediment samples showed that 40 K was in the range from 87 to 593 Bq kg 21 , 137 Cs from 0.8 to 7.3 Bq kg 21 , 226 Ra from 18 to 35 Bq kg 21 , 228 Ra from 4 to 29 Bq kg 21 and 238 U from 14 to 120 Bq kg 21 . In addition, the ERICA Assessment Tool was used for the assessment of dose rates for reference marine organisms using the activity concentrations of the determined radionuclides in seawater. The assessment showed that for the most of the organisms, the dose rates were within the background levels, indicating that the determined values for seawater does not pose a significant risk for the most of marine biota. In the study, the results are critically discussed and compared with other similar studies worldwide. Generally, the activity concentrations of the examined radionuclides did not differ from those reported for the rest of the Mediterranean Sea.

Archives of Industrial Hygiene and Toxicology, 2000

This article brings the results of a method for quality assurance in gamma-ray spectrometry of se... more This article brings the results of a method for quality assurance in gamma-ray spectrometry of seabed sediments. Sediments were collected in selected locations of the South and Middle Adriatic Sea using grab and corer tools. Using our own experimental design, we determined the self-attenuation factors of selected samples. The article also discusses sources of uncertainty in gamma-ray spectrometry, which is another important issue in quality assurance. Together with self-attenuation correction sources of uncertainty are used to calculate the activity concentration for a given sample. The presented procedure demonstrates how a gamma-ray spectrometry experiment should be approached in order to properly account for errors and uncertainties specifi c to a particular sample.

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4±0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adriatic ...

Radiation Protection Dosimetry, 2012

Investigations in the post-Chernobyl period ) of radiocaesium activity concentrations in Adriatic... more Investigations in the post-Chernobyl period ) of radiocaesium activity concentrations in Adriatic pilchards are presented. Compared with pre-Chernobyl period, the Chernobyl nuclear accident caused increase of 137 Cs activity concentrations in pilchards. By fitting the measured 137 Cs activity concentrations to the theoretical curve was estimated to be 1.5+ + + + +0.4 y for 1986-90 and 5.8+ + + + +0.4 y for 1991-2009 and the bimodal behaviour for the ecological half-life of 137 Cs in pilchards has been observed. Estimated annual effective doses received by 134 Cs and 137 Cs intake due to consumption for an adult member of Croatian population are small. Collective dose for the 1986-2009 period was 4.910.3 person-Sv. The observed 134 Cs/ 137 Cs activity ratio in pilchards was similar to the ratio that has been found in other environmental samples.

Environmental Monitoring and Assessment, 2009

The long-term behaviour of l37Cs activity concentrations in air and fallout has been studied in t... more The long-term behaviour of l37Cs activity concentrations in air and fallout has been studied in the city of Zagreb for the post-Chernobyl period as a paft of an extended monitoring program of radioactive contamination of human environment in Croatia. Annual mean l37Cs activity concentrations in air and annual total deposition fluxes (wet plus dry) decreased from 2.8x10'-4 Bq m 3 in September 1986 to 3.0x 10-6 Bq rn-t in last quarler of 2006 and from 6,410 Bq m-' year-t in 1986 to 2 Bq m-2 year"-' in 2006 respectively. By fitting the measured l37Cs activity concentrations to the theoretical curve the ecological half-lives of l37Cs in air and fallout were estimated with respective values of 0.46 and 0.54 years for immediate post-Chemobyl period, increasing to 5.52 and 3.97 years aftetwards. Using the data on '37Cs activity concentrations in air and fallout total caesium deposition velocity of (3.34+ 3.13)x i0-2 ms-l was estimated with median value being 2.13 x 10-2 ms-r. Such relatively high r37Cs deposition velocities compared with pre-Chernobyl ones, are characteristic for the post-Chemobyl period and, according to Stokes' settling law, indicate that the diameters of aerosol particles associated with l37Cs originated from the Chernobyl accident are pretty large, i.e. >1 pm. l3'lcs/r37Cs activity ratio in fallout and in air has been found to be similar to the theoreticaily predicted values, initial value being about 0.5 and decreasing according to differential radioactive decay. The similar ratio has been observed in most of the other environmental samples.

Geologia Croatica, 2014

Geochemical analysis and trace element distribution were performed on the marine sediments from s... more Geochemical analysis and trace element distribution were performed on the marine sediments from short cores (30 to 50 cm) from the Middle (Jabuka and Palagruža pits, depth 230 m and 170 m, respectively) and South Adriatic Sea (depth 1030 m) and the Albanian offshore (50 m depth). The distribution of trace elements (As, Co, Cd, Cu Cr, Ni, Zn, Hg, and Pb) and major elements (Al, Ca and Mn) and mineralogy in the sediments is presented. Sediments are highly heterogeneous and consist of carbonate and detrital aluminosilicate minerals. The main mineral phase is calcite, followed by quartz, feldspars, micas and clay minerals (smectite, chlorite, illite and kaolinite). The cores were dated using 137 Cs. The cores from the South Adriatic Pit and Palagruža Sill gave estimated sedimentation rates of 1.8 mm y -1 and 3.1 mm y -1 in Jabuka Pit. Distributions of Ni and Cr showed that they can be used as tracers of sediment provenance along the southern part of the Eastern Adriatic Current. Calculated enrichment factors for Pb, Cd and Hg are highest in the top 2 cm of the cores. Mercury shows the highest degree of enrichment in 0-2 cm sediment intervals (the highest in the Albania core). Generally the estimated surface enrichment follows the order: Hg>Pb>Cd. No enrichment was found for Zn, Ni and Cr.

Quaternary Geochronology, 2013

Measurement of 226 Ra activity concentrations is often used to estimate supported levels of 210 P... more Measurement of 226 Ra activity concentrations is often used to estimate supported levels of 210 Pb for purposes of geochronology. However, the implicit assumption that supported 210 Pb and 226 Ra are in secular radioactive equilibrium may not always be true because of the migration of an intermediate product, gaseous 222 Rn. As a consequence, supported 210 Pb activity concentration might be lower than the measured 226 Ra value, which was the case in a core collected from the South Adriatic Pit. Here we present a new approach to improve the determination of supported 210 Pb, which is based on correction of 226 Ra activity concentrations using the average ( 210 Pb/ 226 Ra) activity ratio in deeper sediment layers. Using this approach, sedimentation rates for the South Adriatic Pit with a constant rate of supply model and a constant initial concentration model were 0.054 g/cm 2 /a and 0.070 g/cm 2 /a, respectively.

This article brings the results of a method for quality assurance in gamma-ray spectrometry of se... more This article brings the results of a method for quality assurance in gamma-ray spectrometry of seabed sediments. Sediments were collected in selected locations of the South and Middle Adriatic Sea using grab and corer tools. Using our own experimental design, we determined the self-attenuation factors of selected samples. The article also discusses sources of uncertainty in gamma-ray spectrometry, which is another important issue in quality assurance. Together with self-attenuation correction sources of uncertainty are used to calculate the activity concentration for a given sample. The presented procedure demonstrates how a gamma-ray spectrometry experiment should be approached in order to properly account for errors and uncertainties specifi c to a particular sample.

Arhiv za higijenu rada i toksikologiju, 2006

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4 +/- 0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adria...

Radiation Protection Dosimetry, 2010

Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric... more Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric measurements, both in situ and in laboratory, as well as radon measurements in the seawater were performed. Activity concentrations and the associated dose rates due to naturally occurring 232 Th, 238 U and 40 K radioisotopes were determined. Dose rates calculated from in situ gamma spectrometry are in correlation with dose rates calculated from activity concentrations measured in collected samples of pebbles and rocks. In situ gamma ray spectrometry in the seawater has been performed, showing activity concentration of 220 and 240 Bq m 23 for 214 Bi and 214 Pb, respectively due to the presence of magmatic rocks in the seabed. The radium equivalent activity varied from 13 to 53 Bq kg 21 . These values are lower than the limit values, indicating that the radiation hazard is not significant. The highest mean activity concentrations of naturally occurring radionuclides in rock samples collected were found on the islands of magmatic origin.

Radiation Protection Dosimetry, 2012

137 Cs activity concentrations were studied in the sediment profiles collected at five locations ... more 137 Cs activity concentrations were studied in the sediment profiles collected at five locations in the Middle and South Adriatic. In the sediment profiles collected from the South Adriatic Pit, the deepest part of the Adriatic Sea, two 137 Cs peaks were identified. The peak in the deeper layer was attributed to the period of intensive atmospheric nuclear weapon tests (early 1960s), and the other to the Chernobyl nuclear accident (1986). Those peaks could be used to estimate sedimentation rates by relating them to the respective time periods. Grain-size analysis showed no changes in vertical distribution through the depth of the sediment profile, and these results indicate uniform sedimentation, as is expected in deeper marine environments. It was not possible to identify respective peaks on more shallow locations due to disturbance of the seabed either by trawlers (locations Palagruža and Jabuka) or by river sediment (location Albania). The highest sedimentation rates were found in Albania (∼4 mm y 21 ) and Jabuka (3.1 mm y 21 ). For Palagruža, the sedimentation rate was estimated to be 1.8 mm y 21 , similar to the South Adriatic Pit where the sedimentation rate was estimated to be 1.8+ + + + +0.5 mm y 21 . Low sedimentation rates found for the Middle and South Adriatic Sea are consistent with previously reported results for the rest of the Mediterranean.

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4±0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adriatic ...

Arhiv za higijenu rada i toksikologiju, 2015

Phosphogypsum (PG) is a waste product (residue) from the production of phosphoric acid characteri... more Phosphogypsum (PG) is a waste product (residue) from the production of phosphoric acid characterized by technologically enhanced natural radioactivity. Croatia's largest PG deposition site is situated at the edge of Lonjsko Polje Nature Park, a sensitive ecosystem possibly endangered by PG particles. This field study investigates two aspects relevant for the general radiological impact of PG: risk assessment for the environment and risk assessment for occupationally exposed workers and local inhabitants. Activity concentrations of natural radionuclides (238U, 235U, 232Th, 226Ra, 210Pb, and 40K) were measured in the PG (at the deposition site), soil, and grass samples (in the vicinity of the site). The ERICA Assessment Tool was used to estimate the radiological impact of PG particles on non-human biota of the Lonjsko Polje Nature Park. The average annual effective dose for occupationally exposed workers was 0.4 mSv which was within the worldwide range.

Arhiv za higijenu rada i toksikologiju, 2006

This paper gives a review of marine radioecology research in the Adriatic area carried out by the... more This paper gives a review of marine radioecology research in the Adriatic area carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health. Measurements of radioactivity in the Adriatic started in 1963 as a part of an extended monitoring programme of radioactivity in Croatian environment. The main sources of radioactive contamination of the Adriatic Sea are the fallout from past nuclear weapon testing conducted in the atmosphere and the Chernobyl accident. In 2005, the activity concentrations of fission radionuclides were detectable at very low levels in all environmental samples collected on the Adriatic. The 90Sr data obtained from long-term monitoring were used to estimate the upper limit of the Adriatic seawater turnover time, which turned out to be (3.4 +/- 0.4) years. Detailed knowledge about seawater circulation, including the turnover time is essential for planning an overall communal and other wastewater management on the Adria...

Geochemical analysis and trace element distribution were performed on the marine sediments from s... more Geochemical analysis and trace element distribution were performed on the marine sediments from short cores (30 to 50 cm) from the Middle (Jabuka and Palagruža pits, depth 230 m and 170 m, respectively) and South Adriatic Sea (depth 1030 m) and the Albanian offshore (50 m depth). The distribution of trace elements (As, Co, Cd, Cu Cr, Ni, Zn, Hg, and Pb) and major elements (Al, Ca and Mn) and mineralogy in the sediments is presented. Sediments are highly heterogeneous and consist of carbonate and detrital aluminosilicate minerals. The main mineral phase is calcite, followed by quartz, feldspars, micas and clay minerals (smectite, chlorite, illite and kaolinite). The cores were dated using 137 Cs. The cores from the South Adriatic Pit and Palagruža Sill gave estimated sedimentation rates of 1.8 mm y -1 and 3.1 mm y -1 in Jabuka Pit. Distributions of Ni and Cr showed that they can be used as tracers of sediment provenance along the southern part of the Eastern Adriatic Current. Calculated enrichment factors for Pb, Cd and Hg are highest in the top 2 cm of the cores. Mercury shows the highest degree of enrichment in 0-2 cm sediment intervals (the highest in the Albania core). Generally the estimated surface enrichment follows the order: Hg>Pb>Cd. No enrichment was found for Zn, Ni and Cr.

Radiation Protection Dosimetry, 2014

Long-term indoor radon measurements performed by LR 115 track etched detectors in Croatian homes ... more Long-term indoor radon measurements performed by LR 115 track etched detectors in Croatian homes during 2003-04 showed that the arithmetic means of radon concentrations in Lika-Senj and the southern part of Karlovac counties were three times higher (198 Bq m 23 ) than in houses at national level (68 Bq m 23 ). Recently, indoor radon measurements in randomly selected houses were investigated. The obtained values in these new measurements have confirmed the values obtained 10 y ago (the average radon value in 225 investigated houses in this area is 223 Bq m 23 ). Radon concentrations in soil gas were measured in September and October 2012 and 2013 with the AlphaGUARD measuring system. Areas with both elevated indoor radon levels and radon in soil gas were identified (some micro locations in Korenica, Ličko Lešće, Generalski Stol, Slunj and Ogulin) and visually presented in the form of maps using the inverse distance weighting approach.

Radiation Protection Dosimetry, 2009

Thermal waters are known as valuable natural resources of a country. They contain certain degree ... more Thermal waters are known as valuable natural resources of a country. They contain certain degree of natural radioactivity attributable to the elements of the uranium and thorium natural decay series. Among these elements, the most radiotoxic and the most important is radium that exists in several isotopic forms ( 226 Ra and 228 Ra). The focus of attention was the content of radium in samples of thermal and mineral spring water from several spas in Croatia. These waters are mainly used for medical, bathing and recreational purposes, and some of them are used for drinking. Measured activity concentrations of 226 Ra ranged from 87 to 6200 mBq l 21 which, in some springs, exceed the maximal permissible level of 1 Bq l 21 for drinking water. Measured activity concentrations of 228 Ra ranged from 23 to 3480 mBq l 21 . The study showed that radium content for the investigated thermal and mineral waters is below the levels at which negative consequences would arise due to ingestion.

Radiation Protection Dosimetry, 2013

Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sedi... more Artificial and natural radionuclides were determined in the Adriatic Sea in the seawater and sediment samples in the period from 2007 to 2011. The sampling areas were coastal waters of Slovenia, Croatia and Albania, together with the deepest part of the Adriatic in South Adriatic Pit and Otranto strait. Sampling locations were chosen to take into account all major geological and geographical features of this part of the Adriatic Sea and possible coastal influences. After initial sample preparation steps, samples were measured by gamma-ray spectrometry. In the seawater 40 K activity concentrations were in the range from 6063 to 10519 Bq m 23 , 137 Cs from 1.6 to 3.8 Bq m 23 , 226 Ra from 23 to 31 Bq m 23 , 228 Ra from 1 to 25 Bq m 23 and 238 U from 64 to 490 Bq m 23 . The results of sediment samples showed that 40 K was in the range from 87 to 593 Bq kg 21 , 137 Cs from 0.8 to 7.3 Bq kg 21 , 226 Ra from 18 to 35 Bq kg 21 , 228 Ra from 4 to 29 Bq kg 21 and 238 U from 14 to 120 Bq kg 21 . In addition, the ERICA Assessment Tool was used for the assessment of dose rates for reference marine organisms using the activity concentrations of the determined radionuclides in seawater. The assessment showed that for the most of the organisms, the dose rates were within the background levels, indicating that the determined values for seawater does not pose a significant risk for the most of marine biota. In the study, the results are critically discussed and compared with other similar studies worldwide. Generally, the activity concentrations of the examined radionuclides did not differ from those reported for the rest of the Mediterranean Sea.

Radiation Protection Dosimetry, 2010

Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric... more Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric measurements, both in situ and in laboratory, as well as radon measurements in the seawater were performed. Activity concentrations and the associated dose rates due to naturally occurring 232 Th, 238 U and 40 K radioisotopes were determined. Dose rates calculated from in situ gamma spectrometry are in correlation with dose rates calculated from activity concentrations measured in collected samples of pebbles and rocks. In situ gamma ray spectrometry in the seawater has been performed, showing activity concentration of 220 and 240 Bq m 23 for 214 Bi and 214 Pb, respectively due to the presence of magmatic rocks in the seabed. The radium equivalent activity varied from 13 to 53 Bq kg 21 . These values are lower than the limit values, indicating that the radiation hazard is not significant. The highest mean activity concentrations of naturally occurring radionuclides in rock samples collected were found on the islands of magmatic origin.