X‐ray Scattering Evaluation of Ultrastructural Changes in Human Dental Tissues with Thermal Treatment

Micro‐ and ultrastructural analysis of burned skeletal remains is crucial for obtaining a reliable estimation of cremation temperature. Earlier studies mainly focused on heat‐induced changes in bone tissue, while this study extends this research to human dental tissues using a novel quantitative analytical approach. Twelve tooth sections were burned at 400–900°C (30‐min exposure, increments of 100°C). Subsequent combined small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) experiments were performed at the Diamond Light Source synchrotron facility, where 28 scattering patterns were collected within each tooth section. In comparison with the control sample, an increase in mean crystal thickness was found in burned dentine (2.8‐fold) and enamel (1.4‐fold), however at a smaller rate than reported earlier for bone tissue (5–10.7‐fold). The results provide a structural reference for traditional X‐ray scattering methods and emphasize the need to investigate bone and dental tissues separately to obtain a reliable estimation of cremation temperature.     

Bone Mineral Change During Experimental Calcination: An X‐ray Diffraction Study

The effects of calcination (400–1200°C) on pig bones have been studied using powder X‐ray diffraction (XRD) and secondary modifications, such as color change and weight loss. The characterisation by powder XRD confirmed the presence of the crystalline phase of hydroxyapatite, and comparison of the results obtained at different temperatures suggested that at 650°C, all the organic components and carbonate substitutions were completely removed. Accordingly, these samples were white. In addition, the crystallinity degree and the crystallite size progressively increased with the calcination temperature until 650°C, remaining stable until 1200°C. Below 650°C, bone samples presented organic compounds, resulting in background noise in the diffractogram and gray or black color. In addition, impurities in the lattice correspond to low crystallite sizes.     

Weight References for Burned Human Skeletal Remains from Portuguese Samples

Weight is often one of the few recoverable data when analyzing human cremains but references are still rare, especially for European populations. Mean weights for skeletal remains were thus documented for Portuguese modern cremations of both recently deceased individuals and dry skeletons, and the effect of age, sex, and the intensity of combustion was investigated using both multivariate and univariate statistics. The cremains from fresh cadavers were significantly heavier than the ones from dry skeletons regardless of sex and age cohort (p < 0.001 to p = 0.003). As expected, males were heavier than females and age had a powerful effect in female skeletal weight. The effect of the intensity of combustion in cremains weight was unclear. These weight references may, in some cases, help estimating the minimum number of individuals, the completeness of the skeletal assemblage, and the sex of an unknown individual.     

Preliminary Validation of Handheld X‐Ray Fluorescence Spectrometry: Distinguishing Osseous and Dental Tissue from Nonbone Material of Similar Chemical Composition

One of the tasks of a forensic anthropologist is to sort human bone fragments from other materials, which can be difficult when dealing with highly fragmented and taphonomically modified material. The purpose of this research is to develop a method using handheld X‐ray fluorescence (HHXRF) spectrometry to distinguish human and nonhuman bone/teeth from nonbone materials of similar chemical composition using multivariate statistical analyses. The sample materials were derived primarily from previous studies: human bone and teeth, nonhuman bone, nonbiological materials, nonbone biological materials, and taphonomically modified materials. The testing included two phases, testing both the reliability of the instrument and the accuracy of the technique. The results indicate that osseous and dental tissue can be distinguished from nonbone material of similar chemical composition with a high degree of accuracy (94%). While it was not possible to discriminate rock apatite and synthetic hydroxyapatite from bone/teeth, this technique successfully discriminated ivory and octocoral.     

X‐ray Powder Diffraction for Characterization of Raw Materials in Banknotes

We report about the X‐ray powder diffraction characterization of crystalline materials used to produce genuine and counterfeit banknotes, performed with a single‐crystal diffractometer that permits fast and nondestructive measurements in different 0.5‐mm sized areas; 20‐euro denomination genuine banknotes were analyzed, and results were compared with counterfeit banknotes. The analysis shows that the papers used to print real banknotes are composed, as expected, of cotton‐based cellulose and titanium dioxide as crystalline additive, but different polymorphs of TiO₂ for different emission countries are evidenced. The counterfeit banknotes are composed of cellulose based on wood pulp; moreover, an unexpected significant quantity of TiO₂ was found to be mixed with calcite, indicating that the paper employed by forgers is not simply a common low‐cost type. The crystalline index and intensity ratios between the peaks attributable to cellulose and fillers can provide additional information to trace back paper suppliers for forensic purposes.     

Multimethod Resolution of a Small‐Scale Case of Commingling

This study highlights the use of multiple methods for resolving a case of commingled human remains. Skeletal remains were located in a marijuana field in rural northern California by law enforcement. Although initially buried in shallow graves, the remains of two decedents were disturbed by large carnivores and scattered over a wide area. The remains were submitted by law enforcement for forensic anthropological analysis and resolution of commingling. To segregate the remains of the two individuals, a number of methods were employed, including: (i) physical matching of fragmented remains; (ii) articulation to evaluate joint congruence; (iii) visual pair‐matching of bilateral elements; (iv) osteometric pair‐matching; (v) evaluation of taphonomic patterns; (vi) DNA analysis; and (vii) portable X‐ray spectrometry (pXRF). This multimethod approach resulted in accurate resolution of the commingling and facilitated reconstruction of the biological profiles, taphonomic patterns, and trauma analysis for each individual.     

Shark‐Inflicted Trauma: A Case Study of Unidentified Remains Recovered from the Gulf of Mexico*

Abstract: Here, we present a case of an unidentified male whose remains, except for the right arm, were recovered from the Gulf of Mexico 10 years prior to osteological analysis by forensic anthropologists. After the poorly preserved soft tissue was removed and the bones cleaned, forensic analysis revealed an unusual series of hard tissue trauma later attributed by a shark expert as shark scavenging and/or predation. Identified were five unique hard tissue trauma patterns that are bite mark artifacts produced by sharks: punctures without fractures, punctures with associated fractures, striations with bone shaving, overlapping striations, and incised bone gouges. The cooperation among experts provided a comprehensive death case analysis and a better understanding of shark‐inflicted trauma on human skeletal remains.     

Elemental Analysis of Variably Contaminated Cremains Using X‐ray Fluorescence Spectrometry

Analyzing and identifying skeletal remains becomes increasingly difficult when remains have been cremated, especially in cases where the cremated material may have been intentionally contaminated with nonskeletal material. This study examined the potential of X‐ray fluorescence spectrometry (XRF) to detect the presence of nonskeletal contaminants in samples of cremains. Eleven samples of cremains were variably combined with concrete mix and analyzed using XRF. Photon counts of elements in each sample were analyzed, and the coefficient of determination (R²) using unweighted linear regression as a function of percent cremains was calculated. Results showed that with changes in the proportion of skeletal material and contaminant, there were significant (R² > 0.90) changes in detected levels of phosphorus, potassium, zinc, aluminum, and sulfur. The use of XRF is concluded to be a valid approach in the identification of the presence of nonskeletal material in potentially contaminated cremains.     

Practical Considerations in Trace Element Analysis of Bone by Portable X‐ray Fluorescence

Forensic anthropologists are more often turning to nondestructive methods to assist with skeletal analyses, specifically for trace elemental analyses. Portable XRF (pXRF) instruments are versatile and are able to be used in diverse settings or for specimens of a shape and size that cannot be accommodated by laboratory‐based instruments. Use of XRF requires knowledge of analysis parameters such as X‐ray penetration and exit depth. Analysis depth was determined by examining pure elements through known thicknesses of equine bone slices. Correlation between the element's X‐ray emission energy and the depth of reading was observed. Bone surfaces from a small unknown historic cemetery were analyzed before and after sanding of the periosteal surface to observe possible changes in XRF readings based on potential diagenesis. Results validate the pXRF device as a powerful and convenient instrument for nondestructive analysis, while highlighting limitations and considerations for the analysis of osseous materials.     

Indoor Wet Screening of Exhumed Skeletal Remains: A Suggested Procedure for the Preparation of Fragile Evidence for Anthropological Analysis

Abstract: The 2007 exhumation of three children’s graves, located in rural upstate New York and dating to 1979 and 1980, was warranted as their mother had come under suspicion for the death of a child she had been babysitting in late 2006. The local March weather conditions had been wet, and heavy rains fell during the 2‐day process of casket removal. The extremely wet soil and the poor preservation of two wooden caskets increased the likelihood of damage to evidence. After remains’ transport to the forensic center, an indoor wet‐screening station was established so that skeletal elements could be (i) separated from soil matrix and (ii) preserved carefully for analysis. Not only were the remains relatively small and fragile in comparison with those of an adult, but two of the three remains were known to be fire damaged, thus the use of special laboratory preparation techniques was crucial.     

Calcium and Phosphorus Detection Using Benchtop Versus Handheld X‐ray Fluorescence Spectrometers

Elemental analysis of calcium (Ca) and phosphorus (P) has been shown to be useful in differentiating skeletal and nonskeletal material. X‐ray fluorescence spectrometry (XRF) is an attractive, nondestructive technique for forensic anthropologists, and the development of portable XRF instrumentation is promising for field applications. This study examines the performance of handheld XRF instrumentation operated in air compared to a traditional benchtop XRF device that has the ability to control the analysis atmosphere. Both instruments can be used to effectively distinguish skeletal from nonskeletal remains. However, as the measurement atmosphere affects detection levels for calcium and phosphorus, Ca/P ratios obtained from the instruments and analysis conditions were found to differ significantly, with analyses conducted in air showing significantly lower phosphorus detection. Consequently, comparison of Ca/P ratios to conclude skeletal versus nonskeletal origin must be based on data collected under similar analysis conditions.     

Use of a Gelatin‐based Consolidant to Preserve Thermally‐Altered Skeletal Remains,

Thermally altered skeletal remains can be very fragile and fragmented and are typically further fragmented or even destroyed when handled; recovery of such remains from a scene can therefore be extremely challenging. There are few recommendations and no generally accepted practices for preserving burned bone for recovery and transport. Here, we test whether the application of a gelatin‐based consolidant at the scene can preserve thermally altered bone in the condition and relative anatomical position in which it was discovered. A solution of Knox^® brand gelatin and water was applied to burned pig mandibles using a spray bottle. Qualitative and quantitative analysis indicates that the application of the consolidant significantly decreased fragmentation as compared to untreated controls (p < 0.05), with most of the treated mandibles remaining completely intact after recovery and transport to a secondary location. In addition to the effectiveness for preservation, the method is also easy to apply, inexpensive, and reversible.     

A Case of Contested Cremains Analyzed Through Metric and Chemical Comparison

Since the 1980s, cremation has become the fastest growing area of the U.S. funeral industry. At the same time, the number of litigations against funeral homes and cremation facilities has increased. Forensic anthropologists are often asked to determine whether the contents of an urn are actually cremated bone, and to address questions regarding the identity of the remains. This study uses both metric and chemical analyses for resolving a case of contested cremains. A cremains weight of 2021.8 g was predicted based on the decedent's reported stature and weight. However, the urn contents weighed 4173.5 g. The urn contents also contained material inconsistent with cremains (e.g., moist sediment, stones, ferrous metal). Analysis using XRD and SEM demonstrated that the urn contained thermally altered bone as well as inorganic material consistent with glass fiber cement. Although forensically challenging, cremains cases such as this one can be resolved using a multidisciplinary approach.     

SEM and Stereomicroscopic Analysis of Cut Marks in Fresh and Burned Bone

This study documents the prevalence of cut mark characteristics in fresh and burned domestic pig ribs. Stab wounds from single edge serrated and smooth‐edged knives were inflicted in the vertebral and sternal regions of each fresh rib. Each rack of ribs was then divided into vertebral and sternal units. Vertebral units were defleshed and their associated cut marks were examined using a stereomicroscope. Sternal units were burned in an outdoor fire pit and examined with the addition of a scanning electron microscope (SEM). Linear cuts, V‐shaped cross‐sections, mounding, hinge fractures, and wastage were all observed on burned ribs. There was an overall decrease in the prevalence of all features (up to a 40% decrease), regardless of knife type, in burned ribs. Striations within cut marks were not observed in either fresh or burned ribs. Oblique faulting and bone lifts could only be observed using the SEM. Mounding and wastage were obliterated during the burning process. Therefore, cut marks in burned bone should ideally be examined for their characteristics utilizing an SEM.     

Taphonomic Effects of Mechanical Plowing on Buried Juvenile‐Sized Remains

Agricultural activity is a worldwide taphonomic process and can present unique challenges in the recovery of buried remains. Previous research has been mostly within the realm of site formation processes of archeological sites utilizing only surface material. This research expands upon the previous research by incorporating the distribution of subsurface material by the use of archeological excavation techniques. An experiment was conducted utilizing juvenile pig (Sus scrofa) skeletons buried in relative anatomical position at two different depths (15 cm below the surface [cmbs] and 22 cmbs). The burials were then subjected to different intervals of mechanical plowing: one, three, five, seven, or 10 plow passes. The skeletal material was recovered using pedestrian survey followed by hand excavation and screening of all sediments. This research shows that there is a significant relationship between the degree of plowing and the distance skeletal material is distributed and the percentage of material recovered undamaged.     

Forensic Comparison of Automotive Aluminum Wheel Fragments Using Synchrotron Radiation X‐ray Fluorescence with 18‐ and 116‐keV Excitation X‐rays

The performance of synchrotron radiation X‐ray fluorescence (SR‐XRF) spectrometry for nondestructive discrimination of small fragments of automotive aluminum wheels was studied. Fragments (< 500 × 500 μm²) of 45 kinds of wheels were first analyzed by scanning electron microscopy–energy dispersive spectroscopy (SEM‐EDS) and then by SR‐XRF. Despite the Mg/Al intensity ratio being a useful identification index, SEM‐EDS was not efficient enough because of the absence of other meaningful indicators of comparison. Conversely, pairwise comparison was conducted and a 92.9% identification was achieved via SR‐XRF using 18‐keV X‐rays. Trace heavy elements in the high‐energy region were detected by SR‐XRF using 116‐keV X‐rays, and an 82.9% identification was obtained. Combined use of 18‐ and 116‐keV X‐rays allowed 98.2% identification. Hence, SR‐XRF is a powerful tool for nondestructive discrimination of automotive aluminum wheels with high precision using trace elements in a wide energy region.     

Trace Elemental Analysis of Titanium Dioxide Pigments and Automotive White Paint Fragments for Forensic Examination Using High‐Energy Synchrotron Radiation X‐Ray Fluorescence Spectrometry*

Abstract: High‐energy synchrotron radiation x‐ray fluorescence spectrometry (SR‐XRF) utilizing 116 keV x‐rays was used to characterize titanium dioxide pigments (rutile) and automotive white paint fragments for forensic examination. The technique allowed analysis of K lines of 9 trace elements in 18 titanium dioxide pigments (rutile), and 10 trace elements in finish coat layers of seven automotive white paint fragments. High‐field strength elements (HFSE) were found to strongly reflect the origin of the titanium dioxide (TiO₂) pigments, and could be used as effective parameters for discrimination and classification of the pigments and paint fragments. A pairwise comparison of the finish coat layers of seven automotive white paint fragments was performed. The trace elements in the finish coat layers detected by the high‐energy SR‐XRF were especially effective for identification. By introducing the trace element information of primer and electrocoat layers, all the automotive white paint fragments could be discriminated by this technique.     

The Utility of the Samworth and Gowland Age‐at‐Death “Look‐up” Tables in Forensic Anthropology*

Abstract: Accurate age‐at‐death estimates are crucial to forensic anthropologists when onstructing biological profiles aimed at narrowing a missing‐persons list and to allow for timely and efficient identification of an unknown victim. The present contribution evaluates the utility of three new age‐at‐death estimation techniques recently proposed by Samworth and Gowland (2007). Results indicate that, in the samples under study, the Samworth and Gowland estimates from the pubic symphysis and auricular surface perform similar to alternate phase methods. The combined method does not appear to further enhance either the precision or the accuracy of the single pubic symphysis age‐at‐death estimate. In conclusion, these new methods seem to be more robust to distribution deviations than originally proposed by Samworth and Gowland (2007). They are therefore suitable for immediate and reliable forensic usage in the United States and worthy of further research for their use in North American forensic contexts.     

Quantitative Phase Analysis by the Rietveld Method for Forensic Science

Quantitative phase analysis (QPA) is helpful to determine the type attribute of the object because it could present the content of the constituents. QPA by Rietveld method requires neither measurement of calibration data nor the use of an internal standard; however, the approximate crystal structure of each phase in a mixture is necessary. In this study, 8 synthetic mixtures composed of potassium nitrate and sulfur were analyzed by Rietveld QPA method. The Rietveld refinement was accomplished with a material analysis using diffraction program and evaluated by three agreement indices. Results showed that Rietveld QPA yielded precise results, with errors generally less than 2.0% absolute. In addition, a criminal case which was broken successfully with the help of Rietveld QPA method was also introduced. This method will allow forensic investigators to acquire detailed information of the material evidence, which could point out the direction for case detection and court proceedings.     

Forensic Approach to an Archaeological Casework of “Vampire” Skeletal Remains in Venice: Odontological and Anthropological Prospectus*

Abstract: During the years 2006–2007, the Archeological Superintendent of Veneto (Italy) promoted a research project on mass graves located on Nuovo Lazzaretto in Venice, where the corpses of plague deaths were buried during the 16th and 17th centuries. The burials were of different stages and are believed to be the remains of plague victims from the numerous outbreaks of pestilence, which occurred between the 15th and 17th centuries. Among the fragmented and commingled human bones, an unusual burial was found. The body was laid supine, with the top half of the thorax intact, arms parallel to the rachis axis, the articulations were anatomically unaltered. Both the skull morphology and the dimensions of the caput omeris suggest the body was a woman. A brick of moderate size was found inside the oral cavity, keeping the mandible wide open. The data collected by the anthropologist were used to generate a taphonomic profile, which precluded the positioning of the brick being accidental. Likewise, the probability of the brick having come from the surrounding burial sediment was rejected, as the only other inclusions found were bone fragments from previous burials in the same area. The data collected by the odontologist were employed for age estimation and radiological dental assessment. The forensic profile was based conceptually on the “circumstances of death” and concluded that the positioning of the brick was intentional, and attributed to a symbolic burial ritual. This ritual confirms the intimate belief held at those times, between the plague and the mythological character of the vampire.