A re-examination of cremains weight: sex and age variation in a Northern California sample

The reduction of modern commercially cremated remains into a fine powder negates the use of traditional methods of skeletal analysis. The literature on the use of cremains weight for estimating aspects of the biologic profile is limited, often with conflicting results. This study re-evaluates the value of weight in the assessment of biologic parameters from modern cremated remains. A sample of adults was collected in northern California (n = 756), with a cremains weight averaging 2737.1 g. Males were significantly heavier than females (mean = 3233.2 g versus mean = 2238.3 g, respectively; p<0.001). Comparison of this sample with other previously reported samples from southern California, Florida, and Tennessee indicates a consistent sex difference, with the most similar mean values to the Tennessee study. Although cremains weight decreases with age as expected, the relationship is weak; thus, cremains weight cannot accurately predict age-at-death. While sex estimation shows considerable accuracy (86.3% for males and 80.9% for females), sectioning points may be population specific.     

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.     

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.     

Elemental analysis of human cremains using ICP-OES to classify legitimate and contaminated cremains

The Tri-State Crematory Incident in Nobel, GA (February 2001) revealed limitations in traditional human cremated remains (cremains) analytical methodology. The goal of this study was to develop a method for effectively classifying questionable sets of cremains as legitimate or contaminated. Eighty-eight samples of known human cremains, concrete, mixtures of the two, and questionable sets of cremains were acid digested and analyzed for 21 elements by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Variable cluster and principle component analyses identified the seven elements (Sb, B, Li, Mn, Sr, Tl, and V) used to develop discriminant functions to classify questionable sets into two groups: cremains and concrete. The discriminant analysis shows that at the 0.90 probability level, mixtures of 50% or less human content were classified as concrete. Mixtures with 90% human content classified as cremains. Sixty percent and 75% human content mixtures remained in the questionable classification, but as the concentration of human increased in the mixture, the probability of assignment to the known cremains group increased. Most of the questionable human samples classified as cremains. This is a pilot study and cannot yet satisfy Daubert standards for courtroom admissibility, but it indicates that it is possible to determine the legitimacy of cremains using elemental analysis by ICP-OES coupled with multivariate statistical analysis.     

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.     

Identification through X-ray fluorescence analysis of dental restorative resin materials: a comprehensive study of noncremated, cremated, and processed-cremated individuals

Tooth-colored restorative materials are increasingly being placed in the practice of modern dentistry, replacing traditional materials such as amalgam. Many restorative resins have distinct elemental compositions that allow identification of brand. Not only are resins classifiable by elemental content, but they also survive extreme conditions such as cremation. This is of significance to the forensic odontologist because resin uniqueness adds another level of certainty in victim identification, especially when traditional means are exhausted. In this three-part study, unique combinations of resins were placed in six human cadavers (total 70 restorations). Simulated ante-mortem dental records were created. In a blind experiment, a portable X-ray fluorescence (XRF) unit was used to locate and identify the resin brands placed in the dentition. The technique was successful in location and brand identification of 53 of the restorations, which was sufficient to enable positive victim identification among the study group. This part of the experiment demonstrated the utility of portable XRF in detection and analysis of restorative materials for victim identification in field or morgue settings. Identification of individuals after cremation is a more difficult task, as the dentition is altered by shrinkage and fragmentation, and may not be comparable with a dental chart. Identification of processed cremains is a much greater challenge, as comminution obliterates all structural relationships. Under both circumstances, it is the nonbiological artifacts that aid in identification. Restorative resin fillings can survive these conditions, and can still be named by brand utilizing elemental analysis. In a continuation of the study, the cadavers were cremated in a cremation retort under standard mortuary conditions. XRF was again used to analyze retrieved resins and to identify the individuals based on restorative materials known to exist from dental records. The cremains were then processed and the analysis was repeated to determine whether restorative resins could be found under this extreme condition. Under both circumstances, sufficient surviving resin material was found to distinguish positively each individual in the study group. This study showed the utility of XRF as an analytical tool for forensic odontology and also the significance of the role of restorative resins in victim identification, even after cremation.     

Epiphyseal Union of the Cervical Vertebral Centra: Its Relationship to Skeletal Age and Maturation of Thoracic Vertebral Centra

Epiphyseal union stages for cervical vertebral centra (ring epiphyses) were documented for 55 individuals (females and males, ages 14–27 years) from the Terry Collection, using the Albert and Maples method 1, to examine both its relationship to age at death and to thoracic data collected from the same individuals using the same method. Results showed a moderate correlation between cervical ring union and age (r = 0.63, p = 0.000), and a fairly low correlation between cervical and thoracic ring union (r = 0.41, p = 0.002). Paired samples t‐tests yielded a statistically significant difference between cervical and thoracic union mean values (p = 0.01). Union progressed earlier in cervical vertebrae and in females. Results indicated fairly substantial variation in both sexes. Findings may serve as a basic guideline for estimating a general age range at death for unknown skeletal remains and to corroborate findings from other skeletal age indicators.     

Potential Use of Bacterial Community Succession in Decaying Human Bone for Estimating Postmortem Interval,,

Bacteria are taphonomic agents of human decomposition, potentially useful for estimating postmortem interval (PMI) in late‐stage decomposition. Bone samples from 12 individuals and three soil samples were analyzed to assess the effects of decomposition and advancing time on bacterial communities. Results indicated that partially skeletonized remains maintained a presence of bacteria associated with the human gut, whereas bacterial composition of dry skeletal remains maintained a community profile similar to soil communities. Variation in the UniFrac distances was significantly greater between groups than within groups (p < 0.001) for the unweighted metric and not the weighted metric. The members of the bacterial communities were more similar within than between decomposition stages. The oligotrophic environment of bone relative to soft tissue and the physical protection of organic substrates may preclude bacterial blooms during the first years of skeletonization. Therefore, community membership (unweighted) may be better for estimating PMI from skeletonized remains than community structure (weighted).     

A Powder-free DNA Extraction Workflow for Skeletal Samples

The processing of skeletal material poses several challenges for forensic laboratories. Current methods can be laborious, time-consuming, require dedicated equipment, and are vulnerable to contamination. In this study, various sample mass (1 × 50 mg, 3 × 50 mg, and 1 × 150 mg chip(s)) and incubation times (2, 4, and 16 h) were tested using the PrepFiler^® BTA™ Forensic DNA Extraction Kit to digest whole bone chips in lieu of powdering. The most effective method was then applied to bones and tooth fragments collected from contemporary human cadavers exposed to various environmental conditions using an automated platform. Over a third of the samples tested generated full DNA profiles without having to powder the bone/tooth fragment or further alter the manufacturer's protocol. However, for most samples resulting in incomplete STR profiles due to low amounts of DNA, slightly better results were achieved with powdered tissue. Overall, this work demonstrates the potential use of a faster, nonpowdering DNA extraction method for processing skeletal samples as an effective first-pass screening tool.     

Determining Postmortem Interval Using Glycoproteinous Adhesion Deposits by Balanus improvisus on Human Skeletal and Dental Remains

An anthropological analysis was conducted on skeletal and dental remains brought to the Galveston County Medical Examiner's office. The skeletal remains were dry, fragmented, and absent of typical fluvial characteristics. During microscopic examination, semitransparent, circular objects were discovered on the dentition, the mandible, tibial plateau, and distal femur. The objects were glycoproteinous adhesions deposited by the acorn barnacle, Balanus improvisus. B. improvisus is an intertidal barnacle found in estuaries in Galveston Bay. Basal diameter of the adhesions on the dentition were significantly smaller than those found on the postcranial bones (p = 0.010), indicating two consecutive cohorts adhered to the bone and dentition. As settlement typically occurs once a year, this would indicate that the remains were in the fluvial environment for at least 375–410 days. It is important in geographic areas that have prevalent fluvial environments that human remains, particularly dentition, are microscopically examined for marine life evidence.     

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.     

DNA Identification of Commingled Human Remains from the Cemetery Relocated by Flooding in Central Bosnia and Herzegovina

The floods in Bosnia and Herzegovina in May 2014 caused landslides all over the country. In the small village of ?eri?i, near the town of Zenica, a landslide destroyed the local cemetery, relocated graves, and commingled skeletal remains. As the use of other physical methods of identification (facial recognition, fingerprint analysis, dental analysis, etc.) was not possible, DNA analysis was applied. DNA was isolated from 20 skeletal remains (bone and tooth samples) and six reference samples (blood from living relatives) and amplified using PowerPlex^® Fusion and PowerPlex^®Y23 kits. DNA profiles were generated for all reference samples and 17 skeletal remains. A statistical analysis (calculation of paternity, maternity, and sibling indexes and matching probabilities) resulted in 10 positive identifications. In this study, 5 individuals were identified based on one reference sample. This has once again demonstrated the significance of DNA analysis in resolving the most complicated cases, such as the identification of commingled human skeletal remains.     

The Reliability of the Greulich and Pyle Atlas When Applied to a Modern Scottish Population

This study examines the reliability of age estimation utilizing the Greulich and Pyle atlas in relation to a modern Scottish population. A total of 406 left‐hand/wrist radiographs (157 females and 249 males) were age‐assessed using the Greulich and Pyle atlas. Analysis showed that there was a strong correlation between chronological age and estimated age (females R² = 0.939, males R² = 0.940). When age groups were broken down into year cohorts, the atlas over‐aged females from birth until 13 years of age. The pattern for males showed that the atlas under‐estimated age until 13 years of age after which point it consistently over‐aged boys between 13 and 17 years of age. This study showed that the Greulich and Pyle atlas can be applied to a modern population but would recommend that any analysis takes into account the potential for over‐ and under‐aging shown in this study.     

A Test of a Recently Devised Method of Estimating Skeletal Age at Death using Features of the Adult Acetabulum

Estimation of age at death from adult skeletal remains is highly problematic, due in great part to interpopulation variability in skeletal age changes. Thorough testing of aging methods is therefore of key importance. A method recently devised by Calce (Am J Phys Anthropol 148 (2012): 11–23) for placing adult skeletons into three broad age at death classes (17–39, 40–64, 65+ years) on the basis of acetabular morphology is tested on a collection of 18–19th century AD skeletons (N = 185) of documented age at death from London. Results showed that 45% were correctly assigned to age class using this method. This compares with 81% reported by Calce on 20th century North American material. This indicates significant interpopulation differences in the relationship between the Calce acetabular variables and age, even between populations of European ancestry. Until the sources of this variation are better understood, caution should be used before applying this method to estimate age in unknown skeletons.     

The Use of Femoral Neck Axis Length to Estimate Sex and Ancestry

Having multiple reliable methods of estimating sex and ancestry from various skeletal features increases the likelihood of identifying skeletal remains. Femoral neck axis length (FNAL), as measured in living individuals, has been shown to vary by sex and ancestry. FNAL has not, however, been previously measured directly from skeletonized remains and investigated for its potential use in forensic anthropological applications. This research proposes a method for measuring FNAL from skeletal remains, determines the reliability and repeatability of the measurement, and assesses the validity of FNAL in sex and ancestry estimation. Results showed low interobserver error in the measurement of FNAL (TEM = 0.33 mm, R = 0.99). Significant differences in FNAL were found between sexes as well as between American Black, American White, and Native American groups. FNAL can correctly classify sex in ~86% of all cases and is considered valuable to sex estimation. The value of FNAL to ancestry estimation, however, is considered limited.     

Validation of X-ray fluorescence spectrometry for determining osseous or dental origin of unknown material

Forensic anthropological examinations typically involve the analysis of human skeletal remains, but in cases where samples are very small and/or physically compromised, it may first be necessary to determine whether the material is even osseous or dental in origin. X-ray fluorescence spectrometry (XRF) is a technique that reveals the elemental composition of materials and is hypothesized to have utility in such cases. XRF analysis was conducted on a variety of tissues and materials in unaltered and altered (damaged) states. With few exceptions, osseous and dental tissues in unaltered and altered conditions contained characteristic levels of calcium and phosphorus, while other materials did not. Materials could be accurately identified as osseous or dental in origin based on the calcium and phosphorus levels identified by XRF, and we therefore conclude that XRF analysis is a valid and effective means of determining osseous or dental origin of unknown material.     

Shells and Bones: A Forensic Medicine Study of the Association of Terrestrial Snail Allopeas micra with Buried Human Remains in Brazil

Little is known regarding the scavenger fauna associated with buried human corpses, particularly in clandestine burials. We report the presence of 20 shells of the terrestrial snail Allopeas micra, within hollow bones of human remains buried for 5 years, during the process of collecting DNA material. The fact that a large number of shells of A. micra had been found in the corpse and in the crime scene supports the assumption that there was no attempt to remove the corpse from the area where the crime occurred. Despite this, our observations cannot be used to estimate the postmortem interval because there is no precise knowledge about the development of this species. This is the first record of a terrestrial snail associated with a human corpse and its role in this forensic medicine case.     

Validation of the Acetabulum As a Skeletal Indicator of Age at Death in Modern European‐Americans,

Progressive changes in the acetabulum have been used in modern skeletal age estimation, but they have not been completely understood. If their age correlations are weakened by the influence of factors like physical activity and obesity, acetabular changes should not be used for age estimation. To investigate their utility for aging, the acetabular variables of Rissech et al. (2006) were analyzed in 409 modern European‐Americans (Bass Collection, Tennessee). Correlation tests assessed potential associations between acetabular data, osteoarthritis scores (collected per Jurmain, 1990), and documented demographic information (age, body mass index [BMI], metabolic intensity of physical activities). Acetabular changes had statistically significant, positive correlations with osteoarthritis (p < 0.001 in most joints/regions) and age (p < 0.001), indicating their degenerative nature and relevance for age estimation. Acetabular changes showed no associations with BMI or metabolic values, suggesting resistance to obesity and activity effects. These results suggest that acetabular degeneration is a valid skeletal age‐at‐death indicator.     

The Effect of Time on Bone Fluorescence: Implications for Using Alternate Light Sources to Search for Skeletal Remains

Bones fluoresce when exposed to certain wavelengths of shortwave light, and this property can be useful in locating and sorting skeletal remains in forensic contexts. The proteins in bone collagen are largely responsible for its fluorescent properties, but these proteins degrade and denature over time. This study examined the fluorescence of bones from four temporal groups (recent, semi‐recent, ancient, and historic) ranging from 0 to 1064 years before present. Specimens were photographed under 490 nm wavelength light, and fluorescence was quantified by converting intensity to a gray scale value based on the RGB color model using ImageJ^® software. Significant (p < 0.05) differences were found in mean fluorescence between all four temporal groups, and a 0.324 coefficient of correlation indicates a significant (inverse) relationship between fluorescence and time. Bone fluorescence decreases with time, but some fluorescence is retained even in older samples. Fluorescence can therefore be reliably used in many modern skeletal remains searches.