Forensic isoscapes based on intra-individual temporal variation of δ 18O and 206Pb/207Pb in human teeth.

Isotopic signatures used in the georeferencing of human remains are largely fixed by spatially distinct geologic and environmental processes. However, location-dependent temporal changes in these isotope ratios should also be considered when determining an individual's provenance and/or trajectory. Distributions of the relevant isotopes can be impacted by predictable external factors such as climate change, delocalisation of food and water sources and changes in sources and uses of metals. Using Multi-Collector Inductively-Coupled Plasma Mass Spectrometer (MC-ICP-MS) analyses of 206Pb/207Pb in tooth enamel and dentin from a population of 21 ± 1-year-old individuals born circa 1984 and isotope ratio mass spectrometry (IRMS) of δ 18O in their enamel, we examined the expected influence of some of these factors. The resulting adjustments to the geographic distribution of isotope ratios (isoscapes) found in tooth enamel and dentin may contain additional useful information for forensic identification, but the shifts in values can also impact the uncertainty and usefulness of identifications if they are not taken into account.KEY POINTSIsoscapes of 206Pb/207Pb and δ 18O used for geolocation are not static.Within a few years, the enamel and dentin of a person may exhibit measurable differences in 206Pb/207Pb even without changing locations.Changes in climatic patterns tied to rising temperatures are more significant than the direct effect of increasing temperature on δ 18O fixed in tooth bioapatite.Third molar (M3) enamel mineralisation includes material incorporated from before formal amelogenesis takes place.

Time-of-Flight Neutron Diffraction (TOF-ND) Analyses of the Composition and Minting of Ancient Judaean "Biblical" Coins.

TOF-ND elastic scattering of thermal neutrons offers some important advantages over X-ray diffraction (XRD), X-ray fluorescence (XRF), and metallography for the study of archaeological and numismatic problems. Traditional analytical methods are usually destructive and often probe only the surface. Neutrons deeply penetrate samples, simultaneously giving nondestructive bulk information about the crystal structure, composition, and texture (alignment of crystallites) from which thermomechanical manufacturing processes (e.g., cast, struck, or rolled) may be inferred. An analysis of the metal composition and minting processes used for making ancient Judaean bronze and leaded bronze coins from first century BCE and CE is used as a case study. One of the first ND analyses of the temperature used for striking bronze coins is also presented.

Insights into Geographic and Temporal Variation in Fatty Acid Composition of Croton Nuts Using ATR-FTIR.

Croton megalocarpus seedcake oils from 30 different locations in south central Kenya were analyzed for their fatty acid composition using ATR-FTIR to determine the efficacy of a simple procedure for measuring initial geographic and subsequent temporal variation during five months of seed storage. To our knowledge, this is the first report showing variation in how oils in untreated nuts from different locations change during storage, and how these differences are correlated with local environments. These variations are important to forensic authentication efforts and they provide insights into ways to optimize Croton oil composition.

Evaluation of the efficacy of spatiotemporal Pb isoscapes for provenancing of human remains.

Geospatially distributed isotopes (isoscapes) from biogeochemically fractionated processes have been applied in many forensic investigations, such as authentication of food and sourcing of drugs. Provenancing of human remains using isotopes has been hindered by a lack of appropriate isoscapes, by changes in these isoscapes over time, and by various homogenization processes. In this study we create spatiotemporal isoscapes for anthropogenic lead (Pb) for the contiguous United States and Europe using literature data from dated sediments, soils and biological tissues. We compare (206)Pb/(207)Pb isoscapes with isoscapes of δ(13)C, δ(18)O and (87)Sr/(86)Sr to determine their relative efficacy for the forensic identification of human remains. We do this comparison using third molar enamel data from 22 United States Air Force Academy cadets with known life trajectories born between 1983 and 1985. We use these spatiotemporal isoscapes with osteologic analyses, hospital records and isotopic analyses of tooth enamel carbonate from permanent teeth to help identify 32 individuals from unmarked graves found in a forgotten 19th century mental asylum cemetery.

Nondestructive Determination of the Age of 20th-Century Oil-Binder Ink Prints Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FT-IR): A Case Study with Postage Stamps from the Lódz Ghetto.

The ability to determine the production date for a painting or print would be of great benefit in the forensic detection of fakes and forgeries as well as in art history and conservation. Changes in the pigments used at different times have been invaluable in detecting incongruities that suggest fraud, but relatively little work has been published that uses the chemical changes in oil binders as they dry to determine when an ink print or an oil painting was made. Using attenuated total reflectance-Fourier transform infrared (ATR FT-IR) spectroscopy and samples with known dates, we calibrate the drying of oil binders in inks and paints and cross-validate the paints with pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). We apply the ink calibration to a case study involving the age determination of possible philatelic counterfeits from a World War II Jewish Ghetto in Occupied Poland, obtaining a date of 1946 ± 6 (1 s, n = 9) for the genuine stamps, and 1963 ± 16 (1 s, n = 19) for the various reproductions.

Chemical attribution of corroded coins using X-ray fluorescence and lead isotope ratios: a case study from first century Judaea.

Nondestructive analyses using a quadrupole inductively coupled plasma-mass spectrometer (ICP-QMS) and polarizing, multi-target, energy dispersive X-ray fluorescence (PEDXRF) with three-dimensional optics were conducted on Judean coins from the first century BCE and CE to determine the efficacy and limits of these methods for numismatic analyses of coins with a patina. Comparisons with destructive analyses and literature databases demonstrate their value even when corrosion is present. An outstanding question about the dating of Herod Agrippa I or II "canopy" coins that has significance to Biblical historians is used as a case study. Multiple lines of evidence attribute this coin to Agrippa I, with a date of 41 to 45 CE, produced using Faynan (Feinan), Jordan, and Cyprus ores.

Mountain pine beetle attack associated with low levels of 4-allylanisole in ponderosa pine.

Mountain pine beetle (Dendroctonus ponderosae) is the most important insect pest in southern Rocky Mountain ponderosa pine (Pinus ponderosa) forests. Tree mortality is hastened by the various fungal pathogens that are symbiotic with the beetles. The phenylpropanoid 4-allylanisole is an antifungal and semiochemical for some pine beetle species. We analyzed 4-allylanisole and monoterpene profiles in the xylem oleoresin from a total of 107 trees at six sites from two chemotypes of ponderosa pine found in Colorado and New Mexico using gas chromatography-mass spectroscopy (GC-MS). Although monoterpene profiles were essentially the same in attacked and nonattacked trees, significantly lower levels of 4-allylanisole were found in attacked trees compared with trees that showed no evidence of attack for both chemotypes.

Human lead exposure in a late 19th century mental asylum population.

Lead isotope ratios and lead (Pb) levels were analyzed in 33 individuals from a forgotten cemetery at the Colorado Mental Health Institute at Pueblo, Colorado dating to 1879-1899. Isotopic ratios from healing bone fractures, cortical bone, and tooth dentine provide information about sources of Pb exposures over a range of time that illuminates individual's life histories and migration patterns. Historical records and Pb production data from the 19th century were used to create a database for interpreting Pb exposures for these African, Hispanic and European Americans. The analysis of these individuals suggests that Pb exposure noticeably impacted the mental health of 5-10% of the asylum patients in this frontier population, a high number by standards today, and that differences exist in the three ancestral groups' exposure histories.