Hair as a specimen to document tetramethylene disulfotetramine exposure

Tetramethylene disulfotetramine (tetramine) is a rodenticide that has been banned for many years in China. Since 2005, inhabitants of a village in the Henan Province have been suffering from grand mal seizures. To investigate the possibility of tetramine as the cause, we developed a method to determine tetramine in human hair. Sample preparation involved external decontamination, frozen pulverization, and ultrasonication in 2 mL ethyl acetate in the presence of cocaine-d3 as an internal standard. The method exhibited good linearity; calibration curve was linear over a range of 0.1-20 ng/mg hair. The limit of detection for the assay was 0.05 ng/mg hair. Except for one subject (No. 4), all head and pubic hair samples were positive for tetramine. The concentrations of tetramine in pubic hair were significantly higher than those in the same subjects' head hair samples. Because of a long retention in body, segmental head hair analysis cannot provide an accurate exposure history of tetramine in the body.     

Evaluation of the Suchey-Brooks method for aging skeletons in the Balkans

This study has been carried out to examine whether the Suchey-Brooks (S&B) methods could be successfully applied in age assessment of populations from the Balkans. The known-age sample consists of 33 females and 52 males pairs of pubic bones collected from the autopsy cases. Age estimation by S&B method showed an accuracy of 89.74% in males and 72.0% in females. Statistical analysis showed a positive correlation between the actual age of the investigated individuals and age phases obtained by the S&B method, although the mean values of the sixth age category differed significantly compared with the original model. The most reliable indicators in both sexes were the relief of the symphyseal surface, lipping, symphyseal rim, and dorsal margin. The discriminating power of these indicators was the least reliable in distinguishing S&B phases 2 and 3. Based on these results, the appropriate recommendations for aging Serbian populations are made. There was a good agreement between two observers (kappa=0.726).     

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.     

Pubic Symphyseal Age Estimation from Three‐Dimensional Reconstructions of Pelvic CT Scans of Live Individuals

Skeletal age estimation using the pubic symphysis is a reliable and popular practice among forensic anthropologists. In instances in which accessing the skeleton is impossible, such as in the case of living individuals, three‐dimensional (3D) reconstructions of computed tomography (CT) scans can be created and analyzed for aspects of the biological profile. This study examined 3D reconstructions of pelvic CT scans of a sample of 44 live adults to estimate age using the Suchey–Brooks J Hum Evol 1990;5(3):227‐38 method. Images were created using OsiriX software (Pixmeo, Geneva, Switzerland). Estimated age ranges based on the 3D‐CT images captured the true age of the individual at the time of the CT scan 79.5% of the time with good intra‐observer reliability. The features best visualized on the 3D images included the ossific nodule and the pubic symphyseal rim. This study shows that clinical CT scanning parameters are adequate for creating 3D images to be analyzed for age using the pubic symphysis.     

Using PMCT of Individuals of Known Age to Test the Suchey–Brooks Method of Aging in Victoria,Australia

The estimation of an individual's age at death plays a critical role in the investigation of unidentified human remains. The Suchey–Brooks method, which involves the analysis of degenerative morphological changes in the pubic symphysis, is currently widely used to estimate age in adults. This study tested the applicability of the Suchey–Brooks method on a contemporary adult Australian (Victorian) subpopulation by observing three‐dimensional volume‐rendered postmortem computed tomographic (PMCT) reconstructions of the pubic symphysis of 204 individuals aged 15–100 years. Results showed the method was reliable for females (85% correct allocations) but not for males (67% correct allocations). It is therefore recommended that extreme caution be used when applying the Suchey–Brooks method for estimating age at death of an individual in this subpopulation from PMCT images. The results suggest further investigation into alternate age estimation methods is required.     

Evaluation of the Enhanced Computational Methods of Estimating Age-at-Death Using the Pubic Symphyses of a White South African Population

To address problems of reproducibility related to current age estimation methods, the enhanced computational Methods (ECM) were previously developed using a sample of white North American male pubic symphyses and showed promise in improving current techniques. However, given the evidence of sex and population differences in the onset of age markers, this study set out to test the ECM on a white South African sample. The sample consisted of 184 well-preserved os coxae from individuals of known age and sex. Pubic symphyseal surfaces were scanned using the Artec Spider 3D scanner, processed using Artec Studio 10 and analyzed using forAge. Point estimates of age were then compared to the true age of each individual. Results indicate that the ECM performed poorly in a white South African population, with consistent underestimation of age-at-death and weak positive correlations with true age. Despite the low correlations, the ECM did, however, reduce observer error.     

Modeling Bone Surface Morphology: A Fully Quantitative Method for Age‐at‐Death Estimation Using the Pubic Symphysis

The pubic symphysis is widely used in age estimation for the adult skeleton. Standard practice requires the visual comparison of surface morphology against criteria representing predefined phases and the estimation of case‐specific age from an age range associated with the chosen phase. Known problems of method and observer error necessitate alternative tools to quantify age‐related change in pubic morphology. This paper presents an objective, fully quantitative method for estimating age‐at‐death from the skeleton, which exploits a variance‐based score of surface complexity computed from vertices obtained from a scanner sampling the pubic symphysis. For laser scans from 41 modern American male skeletons, this method produces results that are significantly associated with known age‐at‐death (RMSE = 17.15 years). Chronological age is predicted, therefore, equally well, if not, better, with this robust, objective, and fully quantitative method than with prevailing phase‐aging systems. This method contributes to forensic casework by responding to medico‐legal expectations for evidence standards.     

A Comparison of Different Age Estimation Methods of the Adult Pelvis

The adult human pelvis is useful to estimate age because it contains three age indicators—the pubic symphysis, auricular surface, and acetabulum. This study tested the accuracy, inaccuracy, and bias of age estimation from the Suchey‐Brooks pubic symphysis, Osborne auricular surface, Rissech and Calce acetabulum aging methods, and a summary age of these indicators. The study sample consisted of 212 White individuals with known age and sex from the William M. Bass Donated Skeletal Collection. The Rissech method performed the best, was the most accurate method with smallest inaccuracy and bias, followed by the Osborne, Suchey‐Brooks, summary age, and then Calce methods. Though the Pearson correlation showed only the Suchey‐Brooks method to correlate significantly with known age, it is likely the Suchey‐Brooks study sample coincidentally reflected the age distribution of this test sample. Results suggested that Bayesian prediction may improve age estimation and should be applied to other age indicators.     

Quantification of Pubic Symphysis Metamorphosis Based on the Analysis of Clinical MDCT Scans in a Contemporary Malaysian Population

Forensic age estimation methods are biased to sex and population; in general, accuracy is reduced when applied to foreign populations. This study assessed the accuracy of the Suchey–Brooks method in contemporary Malaysian individuals and aimed to formulate population‐specific standards. Multi‐detector computed tomography scans of 355 individuals (165 male; 190 female) of 15–83 years of age were reconstructed using 3D‐volumetric rendering in RadiAnt. Pubic symphyseal phase, bias, inaccuracy, and percentage correct age classifications are examined. Transition analysis was used to develop age estimation standards. High observer agreement (κ = 0.763–0.832) and a positive relationship between age and pubic symphyseal phase (r = 0.884–0.90) were demonstrated. Mean inaccuracies were 8.62 and 8.95 years for males and females, respectively; overall correct classification was 97.8%. Transition ages between phases in males were 18.79, 23.29, 28.85, 43.64, and 61.15 years; in females, the corresponding data were 19.77, 22.53, 32.62, 41.85, and 57.39 years.     

A Test of Hartnett's Revisions to the Pubic Symphysis and Fourth Rib Methods on a Modern Sample

Estimating age at death is one of the most important aspects of creating a biological profile. Most adult age estimation methods were developed on North American skeletal collections from the early to mid‐20th century, and their applicability to modern populations has been questioned. In 2010, Hartnett used a modern skeletal collection from the Maricopia County Forensic Science Centre to revise the Suchey‐Brooks pubic symphysis method and the ??can et al. fourth rib methods. The current study tests Hartnett's revised methods as well as the original Suchey‐Brooks and ??can et al. methods on a modern sample from the William Bass Skeletal Collection (N = 313, mean age = 58.5, range 19–92). Results show that the Suchey‐Brooks and ??can et al. methods assign individuals to the correct phase 70.8% and 57.5% of the time compared with Hartnett's revised methods at 58.1% and 29.7%, respectively, with correctness scores based on one standard deviation of the mean rather than the entire age range. Accuracy and bias scores are significantly improved for Hartnett's revised pubic symphysis method and marginally better for Hartnett's revised fourth rib method, suggesting that the revised mean ages at death of Hartnett's phases better reflect this modern population. Overall, both Hartnett's revised methods are reliable age estimation methods. For the pubic symphysis, there are significant improvements in accuracy and bias scores, especially for older individuals; however, for the fourth rib, the results are comparable to the original ??can et al. methods, with some improvement for older individuals.     

A comparative study on the concentrations of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in head and pubic hair

In this study, the concentrations of 11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in pubic, axillary and beard hair were measured and the correlation between the concentrations of THCCOOH in head and pubic hair from same cannabis users were evaluated. The papers on body hair analysis for THCCOOH were rarely found although police officers submit body hair as a complimentary specimen to forensic laboratories in case cannabis users had no hair. Head, pubic, axillary, and beard hair were collected. All hair samples were cut into 0.5mm segments and decontaminated with methanol, digested with 1 mL of 1M NaOH at 85 °C for 30 min and extracted in 2 mL of n-hexane:ethyl acetate (9:1) two times after adding 1 mL of 0.1N sodium acetate buffer (pH = 4.5) and 200 μL of acetic acid followed by derivatization with 50 μL of PFPA and 25 μL of PFPOH for 30 min at 70 °C. The extracts were analyzed using gas chromatography tandem mass spectrometry operating in negative chemical ionization mode (GC/MS/MS-NCI). We determined the concentrations of THCCOOH in both pubic and head hair. The concentrations of THCCOOH in pubic hair were higher than those in head hair. We also evaluated the concentrations of THCCOOH in body hair (pubic, axillary and beard hair) and head hair according to the positive/negative urine test results. There was no statistically significant difference in the concentrations of THCCOOH in head and body hair according to urine results.     

Quantitative Analysis of the Morphological Changes of the Pubic Symphyseal Face and the Auricular Surface and Implications for Age at Death Estimation

Age estimation methods are often based on the age‐related morphological changes of the auricular surface and the pubic bone. In this study, a mathematical approach to quantify these changes has been tested analyzing the curvature variation on 3D models from CT and laser scans. The sample consisted of the 24 Suchey–Brooks (SB) pubic bone casts, 19 auricular surfaces from the Buckberry and Chamberlain (BC) “recording kit” and 98 pelvic bones from the Terry Collection (Smithsonian Institution). Strong and moderate correlations between phases and curvature were found in SB casts (ρ 0.60–0.93) and BC “recording kit” (ρ 0.47–0.75), moderate and weak correlations in the Terry Collection bones (pubic bones: ρ 0.29–0.51, auricular surfaces: ρ 0.33–0.50) but associated with large individual variability and overlap of curvature values between adjacent decades. The new procedure, requiring no expert judgment from the operator, achieved similar correlations that can be found in the classic methods.     

A Comparative Assessment of the Chen et al. and Suchey‐Brooks Pubic Aging Methods on a North American Sample, ,

Accurately estimating the age‐at‐death of adult human skeletons is fundamental in forensic anthropology. This study evaluates the accuracy of two pubic bone age estimation methods—Chen et al. and Suchey‐Brooks. Specimens were obtained from a known collection of modern pubic bones curated at the Maricopa County Forensic Science Center in Phoenix, Arizona. A sample of 296 left male pubic bones of European ancestry was statistically evaluated via bias, absolute mean error, and intra‐ and inter‐observer error. Results indicate that the two methods are similar; the Suchey‐Brooks method is the most accurate for aging young adults (error c. 7 years), while the Revised Chen et al. method is most accurate for aging middle‐age adults (error c. 6 years). Thus, the Chen et al. method is an important contribution to forensic anthropology for aging older adult skeletal remains. There are, however, some limitations such as subjectivity and the intricate scoring system of Chen et al. method.     

Age Estimation by Amino Acid Racemization in Human Teeth

Abstract: When an unidentified body is found, it is essential to establish the personal identity of the body in addition to investigating the cause of death. Identification is one of the most important functions of forensic dentistry. Fingerprint, dental, and DNA analysis can be used to accurately identify a body. However, if no information is available for identification, age estimation can contribute to the resolution of a case. The authors have been using aspartic acid racemization rates in dentin (D‐aspartic acid/L ‐ aspartic acid : D/L Asp) as an index for age estimation and have obtained satisfactory results. We report five cases of age estimation using the racemization method. In all five cases, estimated ages were accurate within a range ±3 years. We conclude that the racemization method is a reliable and practical method for estimating age.     

Metric Assessment of the Pubic Bone Using Known and Novel Data Points for Sex Estimation,

Biological sex estimation of skeletal remains is essential in forensic and archaeological analyses. Anthropologists most often use the pelvis, which is the most sexually dimorphic element both morphologically and metrically. While nonmetric pubic bone features have been studied extensively, few metric studies have examined this individual bone for dimorphism. For this study, three observers examined three previously identified and ten novel measurements of the pubic body on a modern sample of isolated pubic bones from the Maricopa County Forensic Science Center (FSC), in Phoenix, Arizona (n = 400). A relationship between pubic body measurements and biological sex was demonstrated, with significant correlations. Discriminant function analyses found that five measurements, four of which were novel, discriminated between males (89%) and females (86%). Observer experience level did not significantly impact the results. These five measurements were reliable and show promise for inclusion in metric methods for assessment of sex.     

Fetal Age Determination Through Biparietal Diameter: A Simple Method of Cranial Reconstruction Using Multipurpose Silicone

In forensic medicine, gestational age of fetal remains is a crucial information in several contests, but the classic methods are inadequate when early gestational age needs to be assessed. In the author's experience, the measurement of the biparietal diameter provides more accurate information for this purpose. The status of the fetal head is therefore critical. This work describes an easy technique that allows to reconstruct the cranial volume of the fetus using multipurpose silicone given both the flexibility of the fetal head structure and the inorganic nature of the silicone itself. In conclusion, the determination of the biparietal diameter achieved through the above‐described technique permitted a more accurate estimation of the dating of pregnancy in judicial cases where the fetal remains were incomplete and disrupted.     

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.     

X线片的骨骼年龄判定

目前,对儿童青少年骨骼年龄评价以手腕部及膝部较好,方法也较多,但主观性强,随机误差大。随着计算机图像识别及智能化技术的应用,将使得骨骼年龄评价更为客观、准确。对于成年人X线片骨龄推断,以胸骨、耻骨及锁骨等方法具有一定的应用价值,尚需更广泛的方法学研究以增加推断年龄的方法及准确性。本文介绍了X线片的骨骼年龄判定方法的现状及研究进展。