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Fossil fragments of bone and teeth that are exposed to a humid environment take up fluorine from the surrounding soil and accumulate it in their mineral phase. In cortical parts of long bone diaphysis a fluorine concentration profile can be observed, which carries information on the exposure duration of the buried object in its shape. The distribution of fluorine in a sample however is strongly influenced by environmentally induced processes of bone diagenesis, i.e. alteration in the structure and composition of bone mineral and degradation of the organic components that may make the time information indistinct.

PIGE (Proton Induced Gamma-ray Emission) is a precise and fast analytical technique to determine the quantitative fluorine content and its distribution in cross sections of bone and tooth specimen non-destructively. The simultaneous detection of Ca by PIXE (Proton Induced X-ray Emission) provides additional information on the sample topography. Cracks, alteration haloes and the porosity, which is typical for human bone samples, are parameters which have direct influence on the fluorine uptake and transport during burial. This contribution outlines the combined approach of using PIGE and PIXE measurement to understand some aspects of the complex environmental impact that impedes exposure age dating by fluorine diffusion profiling.

Fluoride (F) distributions in a synthesized hydroxyl apatite (HAp) block of uniform structure and in teeth were measured using in-air micro-PIGE (particle induced gamma-ray emission) and micro-PIXE system, which was developed at the Japan Atomic Energy Agency (JAEA) in Takasaki. We used a nuclear reaction ¹⁹F(p,αγ)¹⁶O to measure F density. The characteristic important feature of this technique is that it can measure F quantitatively in a microscopic area of the specimen placed in air. A surface of the HAp, the enamel buccal surface of a human molar, and a class V cavity wall in dentin were applied a sodium fluoride solution (NaF) four times and immersed in a normal saline solution. After one month, specimens were cut longitudinally. The F distributions were measured from the surface toward the inner part of the cut surface. The F penetration into specimens following NaF application was quantitatively configured in a two-dimensional mapping form. This method is quite useful for characterizing F distribution in a microscopic area of a tooth.

Fluoride (F) distribution in human teeth was measured using an in-air micro-PIGE and micro-PIXE system. Class V cavities in the extracted teeth were prepared with Fluoro-Bond Shake One to provide a thin layer of an F-releasing material (FRM). The cavities were then filled with Beautifil Flow F10 (FRM, Group I) or LITE FIL IIP (non-FRM, Group II). Following a four-year period, specimens were cut longitudinally perpendicular to the cavity floor. The F distribution was measured at the floor of the cut surface. The position including 90% of the intact Ca level was defined as the wall surface. Based on this demarcation, indices of F distribution (surface F concentration and F penetration depth) were determined. Thickness of FRM thin layers varied (≈339 μm) and did not affect F distribution. Both values of F distribution indices in Group I [821–8763 (mean 3797) ppm, 34–668 (mean 241) μm] were significantly larger than those in Group II [0–7064 (mean 1865) ppm, 0–143 (mean 21) μm]. The F distribution in Group I was affected more by the filling material than by the FRM thin layer during the four-year exposure. Methodologies using this system may give insightful information for the development of new dental materials.

The New Zealand capability in Ion Beam Analysis of air particulate samples has been upgraded in recent years. The main equipment change has been the introduction of the ability to analyse samples taken using the Streaker (PIXE International Corporation) sampling system. This is an automated sampler which allows for great flexibility in monitoring programmes by collecting particulates for up to about 70 sampling periods which can range in collection times from seconds to many hours. The IBA analysis for hydrogen on standard filters and for PIXE multi-elemental analysis of the Streaker filters has also been studied with a view to optimising analytical methods.

Water is the most important source of minerals for both human beings and animals. But at the same time, water is also a source of disease due to the contamination of various elements. Therefore, knowledge of the elemental content of water is important. In this work, water samples were collected from areas around Chandigarh and Bathinda district, Panjab, India. Proton-induced X-ray emission (PIXE) and proton-induced gamma-ray emission (PIGE) techniques were used for the determination of heavy and light trace elements, respectively, in wide varieties of water samples. A large number of elements, namely F, Na, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, As, Pb, and U were detected in the samples and results are discussed.

The concentration and distribution of fluorine in mature leaves of Camellia sinensis were determined using micro-PIGE. The elemental concentration was measured as 2210 ± 450 ppm. Fluorine showed clear localization in the epidermis. Fluorine was distributed uniformly in the upper epidermis, suggesting that fluorine was localized in the cytoplasm. On the other hand, extremely concentrated areas of fluorine were observed in the lower epidermis.

Whether fluorine penetrated from material completely incorporates into tooth mineral is a matter of debate, although it is well known that the fluoride from material penetrates directly into tooth structures. The purpose of this study is to determine tooth-bound fluoride uptake from fluoride-containing materials using PIGE/PIXE system at the Wakasa Wan Energy Research Center. Class V cavities in buccal surfaces of eighteen extracted human teeth were drilled and filled with six fluoride-containing materials. After being stored in distilled water for one year, a longitudinal section including materials was obtained from each tooth. Fluorine and calcium distribution of specimens were evaluated using PIGE/PIXE system. After evaluation, the specimens were immersed in 10 mL of 1M KOH solution and were agitated at room temperature for 24 h to remove a KOH soluble fluoride. The specimens were washed with 200 mL distilled water and left to dry. Again, to estimate tooth-bound fluorine (KOH-insoluble fluoride) uptake, the same portion of the specimens after KOH treatment were evaluated using PIGE/PIXE system. It was confirmed that fluorine penetrated from material partly incorporated into tooth mineral. This tooth-bound fluoride have the potential to prevent dental caries after loss of the bond between the filling material and tooth structure.

A microbeam system at the Wakasa Wan Energy Research Center is presented. A magnetic quadrupole doublet is used for the focusing of ion beams from a 5 MV tandem accelerator. Micro-PIXE and micro-PIGE measurements both in the vacuum and air are applicable with this system. Examples of the measurements for tooth and tea leaves are also presented.

For confirming the feasibility of micrometer scale analysis of lithium distribution in the all-solid-state lithium battery using a sulfide-based solid electrolyte, the cross-section of pellet type battery was analyzed by microbeam particle-induced X-ray emission (PIXE) and particle-induced gamma-ray emission (PIGE) measurements. A three-layered pellet-type battery (cathode: LiNbO₃-coated ${\mathrm{\text{LiCoO}}}_2+{\mathrm{\text{Li}}}_{10}{\mathrm{\text{GeP}}}_2{\mathrm{\text{S}}}_{12}$/solid electrolyte: ${\mathrm{\text{Li}}}_{10}{\mathrm{\text{GeP}}}_2{\mathrm{\text{S}}}_{12}$/anode: ${\mathrm{\text{TiS}}}_2+{\mathrm{\text{Li}}}_{10}{\mathrm{\text{GeP}}}_2{\mathrm{\text{S}}}_{12}$) was prepared for the measurements. Via elemental mapping of the cross-section of the prepared battery, the difference in the yields of gamma rays from the ${}^7\mathrm{\text{Li}}{(p,p^{\prime }\gamma )}^7\mathrm{\text{Li}}$ inelastic scattering (i.e., the lithium concentrations) between the composite electrodes and the solid electrolyte layer was clarified. The difference in the number of lithium ions at the composite anode/solid electrolyte interface of ($\mathrm{\Delta }n=0.26\times 10^{-4}$ mol) in the battery can be clearly detected by the microbeam PIGE technique. Therefore, lithium distribution analysis with a micrometer-scale spatial resolution is demonstrated. Further analysis of the cathode/anode composite electrodes with the different states of charge could provide important information to design a composite for high-performance all-solid-state lithium batteries.

A thallium bromide (TlBr) gamma-ray detector was developed for particle-induced gamma-ray emission (PIGE) applications. The PIGE spectrum of a lithium fluoride (LiF) crystal was obtained for the first time using the TlBr detector. This detector was fabricated using a zone-purified crystal with dimensions of approximately 2mm × 2mm × 5mm. An energy resolution of 2.3% full-width at half maximum for 511 keV gamma rays was obtained from the detector at room temperature. The LiF crystal target was irradiated with a 20 MeV proton beam at the Aomori Prefecture Quantum Science Center. Full-energy peaks of 478 keV and 197 keV were successfully detected from lithium and fluorine, respectively, using the TlBr detector in the PIGE experiment.

The objective of this research is to determine whether there is a difference in the Ca, P, Fe, F, Mg, and Sr concentrations in teeth from children with and without cystic fibrosis (CF) as a function of age, sex of the child, maternal smoking habit, maternal drinking habit, and fluoridation of water supply. The nuclear analytical methods used were Proton-Induced X-Ray Emission (PIXE) and Proton-Induced Gamma Emission (PIGE). The findings are: (1) the concentration of Mg is higher in the teeth of children with cystic fibrosis who took antibiotics other than tetracycline (CF+NT) than in non-cystic fibrosis (NCF) teeth for the “female” category; (2) P concentration is less in (CF+NT) teeth for the “age greater than ten” group; (3) Fe concentration is greater for females in the NCF group; (4) Ca and Fe concentrations are lower for CF than for NCF in the “mother smokes” group; (5) F and Sr concentrations for CF+NT are higher for the “mother drinks” group than for the “mother does not drink” group; (6) “mother smokes” shows a depletion of Ca and Fe compared to “mother does not smoke” for CF+NT. (7) “fluoridation of water supply” shows an increase in F, except for NCF teeth.

The construction of a new Nuclear Microprobe at the Livermore multi-user 10 MV FN tandem Laboratory has recently been completed. The facility is primarily used for PIXE, PIGE and Proton energy loss tomography (PELT) in a broad range of multi-disciplinary sciences. Details of the new facility and current applications/programs are discussed.