Experience of using neutron activation analysis on mineral and biological samples: environmental and medical studies

1. Experience of using neutron activation analysis on mineral and biological samples: environmental and medical studies ANA PANTELICĂ “Horia Hulubei” National Institute for Physics and Nuclear Engineering, P.O. Box MG-6. 76900 Bucharest- Măgurele, Romania

2. Introduction Main achievements from environmental and medical studies, based on a thirty-year experience in applying Instrumental Neutron Activation Analysis (INAA) on different mineral and biological samples at “Horia Hulubei” National Institute of Physics and Nuclear Engineering in Bucharest are presented. Neutron irradiation was carried out at the VVR-S reactor in Bucharest (short and long-term irradiation) and TRIGA reactor in Pitesti (long-term irradiation) after VVR-S reactor shutdown in 1997, at a neutron fluence rate of 2.3·1012 cm-2·s-1, and 1-3 ·1013 cm-2·s-1, respectively. Elements investigated by INAA on environmental samples: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Lu, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb, Zn and Zr by long-term irradiation, and Al, Cl, Cu, Dy, I, Mg, Mn, Ti and V by short-term irradiation (44 elements). As standards, reference materials such as W-1 and GSP rocks, IAEA-Soil 7, MA-M-2/TM mussel, MA-B-3/TM fish, IAEA-140 sea weed, WTM water sludge and EOP fly coal ash from the Institute of Radioecology and Applied Nuclear Techniques Kosice (Slovakia), as well as chemical compounds of Al, Ca, Mg, Mn and V were used. Monostandard method was in addition applied in some cases (e.g. Ti and Sr analytes, with Cl and Zn as monostandards, respectively). Experimental • For short half-lived radionuclides, irradiation time of 15 s for sediment, 30 s for water residues, and 45-60 s for biological samples at VVR-S reactor (pneumatic rabbit), decay time of 2-50 min, counting time of 2-10 min were chosen. • For medium and long half-life radionuclides, irradiation time of 4 h at VVR-S reactor, and of 1-2 h at the TRIGA reactor, decay time of 4-5 d, 7-10 d, and 25-30 d, counting time of about 0.5 h, 1.5 h, and 5-22 h, corresponding to three counting runs were used. Quality control in INAA was periodically checked on various mineral and biological Reference Materials from intercomparison runs (major, minor and trace element certification).

3. Introduction (continued) INAA standardization: • relative method,based onmultielement standards (appropriate Reference Materials), as well as on chemical compoundsas comparators was used especially for short half-life isotopes (e.g. Al, Ca, Cl, Mn, V). • monostandard method was complementary used for elements not present or not well determined in the multielement standard (e.g. for Au, Ga, Ag, Hg, Sr determination as standards are taken Na, Co, Fe, Zn). • Data processing: - GAMMAW program for automatic and semi-automatic spectra processing [W. Westmeier. GAMMAW. Version 17.11. Gesellschaft für Kernspektrometrie mbH Consulting, Software, Instruments, Ebsdorfergrund-Mölln, 1996]. - Program to determine concentration values as well as the corresponding statistical counting errors in relative INAA method.

4. I. Danube River and Black Seapollution study • Samples investigated: sediment, water and biota (flora and fauna). • Collaboration with University “Politehnica” Bucharest (Prof. Dr. Iulia I. Georgescu) and National Institute of Hydrology and Water Management (Dr. C. Borcia). • Element concentration levels of water and sediments were collected from ~20 transects of the Romanian sector of the Danube River, from Bazias, km 1072 to the Black Sea mouths (Danube Delta included) and from the Black Sea coast. • Surface water and bottom sediments were collected by NIHWM in expeditionary campaigns, in according with standard methodologies, on different transects along the Danube river, from its entrance in Romania (km 1072.4) to the Black Sea (Danube mouths) and on the Black Sea coast (6.5-37 km offshore, 21-31 m depths to the floor of the sea). • The biota samples examined consisted in: - marine algae (e.g. Enteromorpha linza as Clorophytes and Ceramium rubrum as Rhodophytes), - marine molluscs (Mytilus galloprovincialis and Mya arenaria), polychaete (Melina palmata), and crustacea (Mesopodopsis slabberi Van Bened of Mysidacea specie) - Danube River fish (Alburnus alburnus, Acipenser ruthenus, Carasius auratus, Cyrinus carpio, Ctenopharingodon idaella, Perca fluviatilis, Rutilus rutilus,and Silurus glanis).

6. Danube River and Black Seawater

7. Danube River and Black Seasediment

8. Danube River and Black Seawater

9. Danube River and Black Seasediment

10. Conclusions • It can be seen that, both for water and sediment samples, the highest contents of Al, Co, Cs, Fe, Rb, and Sb were found at the sites located upstream Portile de Fier (the Iron Gates) dam: at Turnu Severin (for water) and Orsova (for sediments). • In the case of water other elements having the highest concentrations at Turnu Severin are Ce, Cr, Hf, La, Mn, Sc, Sm, Sr, Th, V. Relative high elemental contents were determined in the Danube delta at Ceatal Sfantu Gheorghe (Sb, Zn), Sfantu Gheorghe (Co, Cr, Mn, V), Sulina (Hg), and Stambulul Vechi (Hg, Zn), at Bazias, Orsova, Turnu Magurele (Al, Ce, Co, Eu, Fe, La, Sm, Sc, Th) and at Turnu Severin (Zn). • Ag, Au, Ni, Yb, Zr were determined only in some of the water samples at the following concentration levels: ng L-1 (Au, Lu), tens of ng L-1 (Ag, Tb, Yb),hundreds of ng L-1 (Ag), µg L-1 (Ni, Zr), tens of µg L-1 (Ni, Ti). The highest values are found at Turnu Severin for Ag, Au and Yb, at Baziaş for Ni, while Zr has a rather uniform distribution along the river. • A comparison of the concentrations of Au, Ba, Ca, Cl, Co, Cr, Fe, Hg, Mg, Mn, Na, Ni, Se, Yb and Zn in the Danube water with the maximum permissible limits for the surface waters, shows that the limits were exceeded for Fe (at Bazias and Turnu Severin, by a factor of about 2 and 3 respectively) and Zn (at Stambulul Vechi by a factor of about 1.6). • In the case of sediments,the highest concentrations were found at Orsova for As, Ba, Br, K, V, Zn, at Braila for Cr, Mn, Ta, Ti, at Ceatal Sfantu Gheorghe for Hg and Se, at Stambul Vechi for Th and U. Relative high values were found at Cernavoda-km 300 (at about 300 m along the Danube-Black Sea man-made channel, in the vicinity of the CANDU Nuclear Power Plant) for almost all the elements determined The variation of SiO2 lies in the range 42.3 % at East Portita and 87.5 % at Ceatal Sfantu Gheorghe. The level of P2O5 was found ranging between 0.04 % at East Constanta and 0.15 % at East Portita. • The other elements found in sediments are at the following levels: ng kg-1 (Au), hundreds of ng kg-1 (Ag, Hg, Lu, Se, W), mg kg-1 (Ga, Hg, Mo, Nd, Se, W), tens of mg kg-1 (Ga, Hg, Nd, Ni, Se), hundreds of mg kg-1 (Cu), (15050) mg kg-1 (Cl, at Sulina), and in the range of (4.40.5)(6.00.5) g kg-1 (Cl, for the Black Sea sediments).

11. II. Air pollution studies 1. Air pollution (PM10) at Bucharest-Magurele and Stuttgart-Hohenheim was in parallel investigated, during one year (1 Nov. 1993 and 31 Oct. 1994), by a weekly collection of airborne particulate matter on filters. (German-Romanian BMBF Joint Project X055.1/1993-1995 Collaborations with Dr. V. Cercasov and Prof. H. Schreiber, and Institute of Physics and Meteorology, Univ. Hohenheim in Stuttgart, Germany}. 2. The suitability of three lichen species as bioaccumulators of trace elements from atmospheric deposition in zones with different pollution levels and different climates in Germany, Italy and Romania (two locations in every country - Bucharest and Târgoviste in Romania). The investigated species Cetraria islandica, Evernia prunastri and Ramalina farinacea were transplanted from a non-polluted Prealps area in Italy and exposed during 2, 4, 6 and 12 months. (German-Romanian BMBF Joint Project RUM-020-96/1995-1998 - Dr. V. Cercasov, Univ. Hohenheim in Stuttgart, Germany and Prof. G. Caniglia, Univ. Padua, Italy). 3. Characterization of air pollution at six locations with different types of industrial activity (Afumati, Baia Mare, Copsa Mica, Deva, Galati, Oradea) and a background site (Fundata) in Romania using transplant lichen bioaccumulators (Evernia prunastri and Pseudevernia furfuracea exposed during 6 and 12 months), bulk (wet and dry) deposition, and airborne particulate matter collection on filters. ICA1-CT-2000-70023 Center of Excellence EU Project IDRANAP (InterDisciplinary Research and Applications based on Nuclear and Atomic Physics, WP2), during 2000-2004 Collaboration with Univ. Hohenheim in Stuttgart, Germany (Dr. V. Cercasov), IRI TU Delft, The Netherlands (Dr. B. Wolterbeek and Dr. P. Bode) and Norwegian Univ. Trondheim, Norway (Prof. E. Steinnes).

12. Transplant lichen biomonitoring Comparison of elemental concentrations in Pseudevernia furfuracea before exposure (“zero level”) and after 12- months exposure at Copsa Mica (non-ferrous industry), Deva (coal-fired power plant and cement industry) and Galati (metallurgical industry)

13. Enrichment Factors for Evernia prunastri after 6 months of exposure

14. Fe, V and Zn in bulk deposition (μg) compared with lichen enrichment (mg kg-1) during 6 months of exposure

15. Conclusions • Both Evernia prunastri and Pseudevernia furfuracea lichen species showed significant enrichments in almost all of the investigated elements (Ag, As, Au, Cd, Co, Cr, Cu, Fe, Ni, Pb, S, Sb, Se, V, and Zn). • In correlation with the total deposition, their magnitude was found to differ strongly from one location to another, as a function of the atmospheric availability of these trace elements. • The values of the element concentrations determined in air, relative to a “reference station”, confirmed the pollution pattern shown by the bioaccumulators. • The relative degree of air pollution due to the anthropogenic and/or natural (crustal) contribution at six locations in Romania, relative to the background site Fundata, could be described by the following relationships: a) Anthropogenic contribution: Copşa Mică >> Baia Mare > Afumaţi, Galaţi, Deva > Oradea. b) Crustal contribution: Galaţi > Afumaţi > Copşa Mică > Deva > Baia Mare, Oradea. The anthropogenic pollution was mainly due to the following types of industrial activities: non-ferrous (Copşa Mică), metallurgic (Galaţi), coal power plant and cement factory (Deva), non-ferrous mining (Baia Mare), agriculture and mixed industry (Afumaţi, near Bucharest), traffic and mixed industry (Oradea).

16. III. Environmental impact of TURNU fertiliser plant Samples investigated: - soil and vegetation (tree leaves, potato, carrot, and corn) collected at different distances from the plant; - workplace air (airborne particulate matter and dust deposition) and tap water; - hair and nail biosubstrates from the occupational exposure. EU INCO-Copernicus project «Workplace monitoring and occupational health-related studies at some selected phosphate fertilizer plants in Russia, Uzbekistan, Poland, and Romania» (2000-2003) Collaboration with Univ. “Politehnica” Bucharest (Prof. E. Pincovschi – Project coordinator in Romania) and JINR Dubna (Dr. M. Frontasyeva); EU Project co-ordinator: Dr. P. Bode, IRI-TU Delft, The Netherlands.

17. Concentration levels in soil samples in the vicinity of the fertilizer plant

18. Ratio to control forelemental concentrations in crop vegetation and host soil in the vicinity of TURNU plant

19. Conclusions • Variation with the distance to the plant of the elemental concentrations in soil samples were observed as follows: - Decreasing of Ag, As, Au, Co, Fe, K, Ni, Rb, Sb, Sc, Se and Zn concentration; - Increasing of Rare Earths, Sr and Zr concentration, with a maximum at 10 km; - Increasing of Ca concentration on East and West directions, with no regular variation on Northeast and Northwest directions. • Relative to the control zone, significant higher concentrations were found for various elements in carrot and potato, and to a lower degree also in the maize (ear of corn) grown in the vicinity of the fertiliser plant. • Both potato and carrot pulp were found to accumulate Fe, Th, Ce, Cr, and Sb, their concentration ratio to control samples ranging between 2 and 10 for the potato and ranging between 50 and 113 for carrot samples. In addition, carrot pulp was found to accumulate As, La, Se, Zn, Sr and U (concentration ratios between 3 and 36). • Fe, Mg, Mn, Ca, Cl, and K concentration values in carrot pulp, as well as Fe and Cl in potato pulp were found to exceed the normal levels, while those of As, Zn, and Hg were found to be lower than the maximum allowable levels in Romania. • Ratios below unity in the vicinity of the fertiliser plant were determined for Br, Cs, and Rb in all maize samples examined.

20. IV. Trace elements in tumoral skin tissues Modifications of trace elements concentration in four types oftumoral skin tissues were assessed relative to a normal tissue. VIASAN / R&D program of the Ministry of Education and Research in Romania, during 2001-2004. Collaboration with "Carol Davila" Medicine and Pharmacy University Malign tumors: Squamous Cell Carcinoma (SCC) – 7 Basal Cell Carcinoma (BCC) - 2 Malignant Melanoma (MM) - 4 Benign tumor: Nevocytic Nevus (NN) tissue -2 Control samples: skin tissue from patients suffering of cutaneous cancer, but from a normal area determined by ahistopathological diagnose - 5 .

21. INAAin medical field (continued) Ratios of the elemental concentrations in tumor relative to normal skin tissue (SCC - Squamous Cell Carcinoma, BCC - Basal Cell Carcinoma,MM – Melanoma, NN – Nevocytic Nevus).

22. Conclusions • For some of the elements measured an enhancement of concentration in different tumor tissues (especially in the benign one) was observed by comparing with the normal tissue: e.g. Ag, Au, Ba, Ca, Ce, Co, Cr, Cs, Eu, Fe, Rb, Sb, Sm, Sr, Zn, Zr in the NN type benign tumor, as well as Sb in all types of the tumor tissues examined. • These results are in agreement with those we previously obtained by PIXE for P, S and K, as well as in a smaller degree for Ca, Fe and Zn (Ciortea et al., 2002). • Similarly, an enhancement of Zncontent in skin carcinoma was determined by Allen et al., 1978. • These results suggest that important disturbances could appear in malign and benign skin tumor tissues during their growth, both for essential and non-essential elements.

23. International Intercomparison Runs (24 exercises, 37 ReferenceMaterials) • 1. Sediment • IAEA-SD-M-2/TM (1988) • IAEA-356 (1992) • 2. Soil IAEA-Soil 7 (1984) • S-VM, S-MS, S-SP (Kosice, Slovakia, 1992) • SO-1 (Krakow, Poland. 1986) • 3. Fly coal ash • ENO, EOP, ECH (Kosice, Slovakia. 1984) • 4. Water sludge • WT-L, WT-M, WT-H (Kosice, Slovakia, 1995) • 5. Copper smelting flue dust • KHK (Kosice, Slovakia, 1988) • 6. Uranium phosphate ores • IAEA/S-17, S-18, S-19 (1984) • 7. Plants • IAEA-331 (spinach), 1993 • IAEA-359 (cabbage), 1993 • CL-1 (cabbage leaves), Krakow, Poland, 1986 • P- Alfalfa (lucerne), Kosice, Slovakia • P-ACHK (green algae), Kosice, Slovakia (1989) • IAEA-0140 (Fucussp. - marine algae, 1996) • IAEA-0390 (three different level algae IAEA-0391/ IAEA-0392/ IAEA-0393), 1996 INCT-TL-1 (Tea leaves), INCT-MPH-2 (Mixed Polish herbs), 2002 INCT-CF-3 (Corn Flour), INCT-SB-4 (Soya Bean Flour), 2004 (in progress) 8. Biological materials • IAEA-V8 (rye flour), 1982 • MP-1 (wheat flour), Krakow, Poland, 1988 • IAEA-155 (milk powder), 1989 • IAEA-MA-M-2/TM (mussel homogenate), 1985 • IAEA-MA-B-3/TM (shrimp tissue), 1988 • IAEA-350 (tuna fish, 1989)

24. En scores of the participants for the analysis of the intercomparison sample.

25. IAEA-0140 Fucussp. - marine seaweed,mg·kg-1,*g·kg-1(1998)109 laboratories from 51 countries (60 elements)

26. INCT-MPH-2 (Mixed Polish Herbs) - 109 labs, 19 countries

27. INCT-TL-1 (Tea Leaves) - 109 labs, 19 countries

28. Water sludge - WT-L (Low level concentrations)