S.K. Sahoo 1 *, Z.S. Zunic 2, R. Kritsananuwat 1, H. Arae 1 and S. Mishra 1

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1 S.K. Sahoo 1 *, Z.S. Zunic 2, R. Kritsananuwat 1, H. Arae 1 and S. Mishra 1 1, Japan 2 Institute of Nuclear Sciences Vinca, Beograd, Serbia sahoo@nirs.go.jp 3rd TRE-ICEP Veszprém-Hungary, May 16-18, 2012

2 Introduction In the past few years human hair and nail have been recognized as the invaluable tissues for monitoring human environmental exposure. The content of elements in human hair and nail is a good alternative indicator of the public and occupational exposure to natural radionuclides and other toxic metals over a long period of months or even years. Compared to other types of biopsy, hair and nail have different uses and even advantages over blood, urine or other accessible tissue. But in some regions, there is a conservative tradition or faith about hair and nail so it is difficult to collect hair or nail sample from that area.

3 Advantages of hair and nail Hair and nail have many of the characteristics of an ideal tissue for assays since they can be: Painlessly removed Easily collected and transported Highly stable at room temperature Normally discarded Contained normally relatively higher elemental concentration than other body fluids and tissues Reflected the actual exposure over a period of months, or even year. (Blood and urine tend to show current or recent body status)

4 Sampling location Niška Banja, a spa town of Serbia is located in the quaternary alluvium of River Nišava along the contact of the Koritnik limestone and travertine rock.

5 Sampling location The high value of 226 Ra concentration in soil and indooroutdoor radon concentrations found around Niška Banja make this region a high background radiation area. Radionuclide in soil Concentration (Bq/Kg) 226 Ra Th K Rn Concentration Bq/m3 Indoor 6000 Outdoor 168

6 Sample collection 27 hair samples and 26 nail samples were collected from informed volunteers living in Niška Banja by cutting with ceramic equipment and stored in sealed plastic bags to avoid any contamination Transport to National Institute of Radiological Sciences (NIRS), Japan for chemical charaterization

7 Analytical procedures Hair and Nail samples Washed with ultra-pure water and acetone Hair samples Dry ashing 550 C 15 h Microwave Digestion 6 ml 68% HNO 3 and 1 ml 35% H 2 O 2 Nail Samples Acid digestion on a hot plate 6 ml 68% HNO 3 1 ml 35% H 2 O 2 U, Th and trace elemental analysis using ICP-MS and Rh as an internal standard

8 Advantages of ICP-MS Inductively coupled plasma-mass spectroscopy (ICP-MS) is the analytical technique of choice because of its: Multi-element capability Low detection limit High sensitivity Ability to measure a large range of concentration Simple experimental procedure

9 ICP-MS Plasma Frequency (MHz) RF power (kw) HP-4500 Argon flow, l/min Plasma Auxillary Carrier Nebulizer Sampling distance, mm Sample uptake rate, ml/min Babington type Data acquisition Mode Number of point per peak Number of scan sweeps Dwell time per point, s Scan mass range, a.m.u. Peak jumping mode

10 Certified reference materials BCR-397 Human hair Cd, Hg, Pb, Se, Zn, As, Cu, Ni NIES-13 Human hair Cd, Cu, Hg, Pb, Sb, Se, Zn, Ag, Al, As, Ba, Ca, Co, Fe, Mg, Mn, Na, V JLK-1 Sediment Ag, As, Au, Ba, Be, Br, C, Cd, Cu, Cs, REEs, Th, U SRM 1547 Peach leaves Al, As, Ba, B, Cd, Ca, Cr, Cu, Pb, Mn, Ni, Sr, Th, U SRM 1570a Spinach leaves Al, As, B, Cd, Co, Cu, Pb, Mg, Mn, Ni, Sr, Th, U Use for validation of analytical procedure and accuracy evaluation. CRMs were digested by micorwave digestion. A good agreement in the measured values with the certificate was achieved.

11 Dry ashing - Microwave digestion Dry ashing - Microwave digestion Dry ashing - Microwave digestion Dry ashing - Microwave digestion Comparison of sample preparation 5 4 R² = 0,9952 Mn (µg/g) 6 5 R² = 0,9975 Sr (µg/g) Open digestion Open digestion 0,10 0,08 0,06 R² = 0,9967 U (µg/g) 0,004 0,003 R² = -0,77 Cs (µg/g) 0,04 0,002 0,02 0,001 0,00 0,00 0,02 0,04 0,06 0,08 Open digestion 0,000 0,000 0,002 0,004 0,006 0,008 Open digestion

12 Elemental concentration in hair Element Present study (Niska Banja) Published * Mean S.D. Median range range Th U Cd Cs Cu Mn Ni Sr * I. Rodushkin, M.D. Axelsson (2000) G. Samanta et al. (2004)

13 Elemental concentration in nail Element Present study (Niska Banja) Published * Mean S.D. Median range range Th U Cd Cs Cu Mn Ni Sr * I. Rodushkin, M.D. Axelsson (2000) G. Samanta et al. (2004)

14 Comparison of elemental concentration in hair from present study with reported values of healthy individuals from different countries Niska Banja South Serbia (1) Sweden (2) Italy (3) Ghana (4) Japan (5) New Zealand (6) USA (7) England (8) Norway (9) U (ng/g) Mn ( g/g) Ni ( g/g) Cu ( g/g) Sr ( g/g) Cd ( g/g) Cs (ng/g) < S.K. Sahoo et al. (2012) 2. Rodushkin et al. (200) 3. Sonofonate et al. (2000) 4. Amartey et al. (2011) 5. Kamakura (1983) 6. Ward (1986) 7. ML (1989) 8. Ward (1988) 9. Gellein et al. (2008)

15 Data comparison with other populations The elemental concentration in hair and nail samples in the publications had a wide distribution range due to: geological differences Food habit method and detection limit of analysis The data obtained in our study on the high background radiation area are in agreement with previous publications dealing with other population.

16 Average concentration in hair Element Niska banja Range ( g/g) South Serbia DU area Range ( g/g) Th U Cd Cs Han Pijesak Niska banja Cu Mn Ni Gornja Stuba Bratoselce Sr a high background radiation area an evidence of depleted Uranium area

17 Average concentration in hair Han Pijesak Niska banja Gornja Stuba Bratoselce

18 Sample Hair U Th H H H H H H H H H H H H H H H H H H H H H U and Th concentration in hair

19 Sample Nail U Th N N N N N N N N N N N N N N N N N N N N N U and Th concentration in nail

20 Elemental concentration in hair and nail

21 Elemental concentration in hair and nail

22 Considering the column charts, elemental in hair and nail can be grouped into 3 groups as follow: 1. Concentration in Hair > Nail : Cu, Sr, U Cu is absorbed by Keratin in hair very well 2. Concentration in Hair < Nail : Cd, Mn, Ni, Th 3. Concentration in Hair <<< Nail : Cs

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29 Conclusion ICP-MS is a powerful tool for multi-element analysis of hair and nail samples that can provide elemental coverage and low detection limits. Hair and nail samples can be as the good biological material for worldwide environmental monitoring. The main problem of using hair and nails is the external or surface contamination and lack of standardized methodology.

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