Traveling There and Back Again: A Fingernail's Tale

This study focuses on the examination of stable isotope biomarkers in human fingernails of travelers who ventured away from Salt Lake City, UT and subsequently returned. Here, we describe three case studies examining: individual travelers (n = 4), paired travelers (n = 2), and a traveler (n = 1) who repeatedly left and returned. Our case studies examined the influences of dietary and drinking water inputs on fingernail stable isotope profiles for reconstructing travel histories. Stable isotope data were compared with theoretical and predictive models that laid the groundwork for anthropological and forensic geospatial reconstruction of travel histories. Drinking water inputs strongly influenced stable isotope profiles and the patterns observed were consistent with reported travel histories. Finally, observed fingernail stable isotope ratio data were consistent with modeled rates of stable isotope turnover and transition to expected values for the new environment. The results of our study further support the use of fingernail tissues for travel history reconstruction.     

Metric forensic anthropology decisions: Reliability and biasability of sectioning-point-based sex estimates

Subjective decisions make human cognitive processes more susceptible to bias and error. Specifically, research indicates that additional context biases forensic anthropologists’ morphological analyses. To address whether metric analyses are also subject to bias, we conducted a pilot study in which 52 experienced osteologists measured a difficult-to-classify human femur, with or without additional contextual information. Using a metric sectioning-point sex-estimation method, participants provided a sex estimate for individual skeletal element(s) and, when given multiple elements, the combined skeletal assemblage. Control group participants (n = 24) measured only the femur. In addition to the femur, bias group participants (n = 28) either measured a female humerus and viewed a female-biasing photograph (n = 14) or measured a male humerus and viewed a male-biasing photograph (n = 14). We explored whether the experts in the different groups would differ in: (1) femoral measurements; (2) femoral sex-estimation conclusions; and (3) final sex-estimation conclusions for the skeletal assemblage. Although the femoral measurements and femoral sex estimates were comparable across groups, the overall sex estimates in the female-biased group were impacted by contextual information—differing from both the control and male-biased groups (p < 0.001). Our results demonstrate that cognitive bias can occur even in metric sex-estimation conclusions. Specifically, this occurred when the metric data and single-element sex estimates were synthesized into an overall estimate. Thus, our results suggest that metric methods are most vulnerable to bias when data are synthesized into an overall conclusion, highlighting the need for bias countermeasures and comprehensive statistical frameworks for synthesizing metric data to mitigate the effects of cognitive bias.     

The Validity of Ear Prediction Guidelines Used in Facial Approximation*,†,‡

Abstract: This study examined eight previously published ear prediction methods by Welcker, Gerasimov, Fedosyutkin and Nainys, and Broadbent and Mathews. Computed tomography scans of 78 living adults (n₁) did not support any of these previously published recommendations. Free earlobes were found to accompany protruding supramastoid crests (Pearson’s χ² < 0.05); and ear length [l] and width [w] differed by sex (p < 0.05), correlated with age (r = 0.38[l]; 0.32[w]), and correlated with facial height (r = 0.37[l]; 0.30[w]). New regression equations (for ear length and width) were generated using these variables in several samples and, where possible, cross‐validated using independent data (n₁ = 78, n₂ = 2190, n₃ = 1328, n₄ = 1010, and n₅ = 47). As a result of these analyses, four valid and tested methods for ear prediction were identified, but large degrees of error continue to make accurate prediction of the ear, from the skull, problematic.     

Forensic applications of stable isotope analysis: Case studies of the origins of water in mislabeled beer and contaminated diesel fuel

This paper describes the use of oxygen (¹⁸O) isotope analysis of water contained in two different materials — beer and diesel fuel — involved in the resolution of two separate cases. In the first case study, it was possible to demonstrate that a sample of beer labelled as premium brand in fact belonged to a cheap brand. The second case related to the contamination of diesel fuel from a service station. The diesel fuel contained visible amounts of water, which caused vehicles that had been filled up with it to become defective. For insurance purposes, it was necessary to determine the source of water. The δ¹⁸O values for the water of nearly all samples of diesel was close to the δ¹⁸O of local tap water at the filling station.     

Resident and Nonresident Fingernail Isotopes Reveal Diet and Travel Patterns,,

Global travel has increased, and having a diagnostic tool to distinguish residents from visitors would be valuable. This study examined stable isotope biomarkers of fingernail tissues of resident (n = 26) and nonresident (n = 22) participants in Salt Lake City (SLC), UT, from 2015 to 2016. The purpose of this research was to determine whether fingernail isotopes could be used for reconstructing geolocation movements and to examine the convergence in nonresident fingernail isotopes to that of the resident signal following their arrival to SLC. Resident isotope values defined a baseline to make comparisons to. Initial nonresident hydrogen and oxygen isotope values were correlated with precipitation isotopes of their prior location. Fingernail isotope turnover rates were rapid and nonresident isotopes were indistinguishable from residents after ~71–90 days. The results of our study highlight the utility of stable isotope measurements of fingernail clippings to examine travel history reconstruction that could aid in identification of human remains.     

Effectiveness of Femur Bone Indexes to Segregate Wild from Captive Minks,Mustela vison,and Forensic Implications for Small Mammals

Utilization of free‐living populations of endangered wildlife species is usually strictly prohibited or restricted. Farming of endangered species can provide products that are in demand as a countermeasure. A novel forensic issue arises because it becomes necessary to discriminate the origin of given wildlife products. We tested the effectiveness of five measurements and four indexes of femur bone using farmed minks (n = 40) and escapees (n = 32). Results showed all measurements, namely body mass (L_f), body length (M_f), femur mass (V_f), femur length (M_b), and femur volume (L_b), were highly discriminatory. However, they are susceptible to the influence of nutrition level and sex. Femur length index (I_fl), femur linear density (D_l), and femur volume density (D_v) eliminated the influence of level of nutrition and were highly effective. However, I_fl and D_l were influenced by sex (p = 0.000). Because D_v was not influenced by sex (p = 0.683) and was highly effective, it was the preferred index.     

Detection of Mitragynine in Mitragyna Speciosa (Kratom) Using Surface-Enhanced Raman Spectroscopy with Handheld Devices

A simple, quick, selective, sensitive, and effective field-friendly method capable of being used by nonexperts has been developed for detecting mitragynine in Mitragyna speciosa (kratom) using surface-enhanced Raman spectroscopy (SERS). Over 100 samples and blanks (known to be either positive or negative for the presence of mitragynine) were examined in duplicate using five identical handheld Raman spectrometers, which provided a data set of over 1,000 examinations. Based on the results of these analyses, the method yielded a true-positive rate of 99.3%, a true-negative rate of 97.9%, a false-positive rate of 2.1%, and a false-negative rate of 0.7%. The average minimum detectable concentration (C_m) of mitragynine that reproducibly yielded a match for one of the library spectra on all five instruments was determined to be 342 ng/mL (ppb). This C_m value is a conservative estimate considering that the extraction process was not fully optimized by this study, which was not necessary since the C_m value achieved was well below typical mitragynine concentrations in kratom (1.3–2.3%). The method is ideal (i) for prioritizing samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify mitragynine and (ii) for field use at international mail facility (IMF) satellite laboratories to help interdict kratom and prevent this dangerous product from reaching the U.S. supply chain.     

Forensic Dental Age Estimation by Measuring Root Dentin Translucency Area Using a New Digital Technique

Dentin translucency measurement is an easy yet relatively accurate approach to postmortem age estimation. Translucency area represents a two‐dimensional change and may reflect age variations better than length. Manually measuring area is challenging and this paper proposes a new digital method using commercially available computer hardware and software. Area and length were measured on 100 tooth sections (age range, 19–82 years) of 250 μm thickness. Regression analysis revealed lower standard error of estimate and higher correlation with age for length than for area (R = 0.62 vs. 0.60). However, test of regression formulae on a control sample (n = 33, 21–85 years) showed smaller mean absolute difference (8.3 vs. 8.8 years) and greater frequency of smaller errors (73% vs. 67% age estimates ≤ ±10 years) for area than for length. These suggest that digital area measurements of root translucency may be used as an alternative to length in forensic age estimation.     

Isotopic fractionation of carbon and nitrogen during the illicit processing of cocaine and heroin in South America

The forensic application of stable isotope analysis to cocaine and heroin for geolocation of exhibits must take into account the possible enrichment and/or depletion of 13C and 15N during the illicit manufacturing process. Continuous-flow elemental analysis-isotope ratio mass spectrometry was utilized to measure changes in the stable isotope ratios of carbon and nitrogen for both cocaine (N = 92) and heroin/morphine (N = 81) exhibits derived from illicit manufacturing processes utilized by South American clandestine chemists. In controlled settings in South America, there was no siginficiant carbon isotope fractionation during the conversion of cocaine base to cocaine HCI using current illict methodologies. In contrast, nitrogen isotope fractionation for this conversion was 1 per thousand. There was a kinetic carbon isotope ratio fractionation during the acetylation of Colombian morphine to heroin and as a result heroin exhibits will almost always have more negative delta13C values than the original morphine. There was an isotopic fractionation against 15N during the acetylation of morphine base to heroin base, but this effect was not expressed since all of the heroin base was precipitated during the manufacturing process. However, the clandestine process of converting a single batch of heroin base usually involved two consecutive crops of heroin HCl and the latter crop was isotopically depleted as expected from a Rayleigh distillation process. When heroin was deacetylated to morphine, the morphine produced resulted in delta13C values that were indistinguishable from the original morphine. The kinetic carbon isotope fractionation factor for the South American process of morphine acetylation was -1.8 per thousand, allowing calculation of the delta13C values of the acetic anhydride from deacetylated heroin delta13C values.     

Is There a Correlation Between Footstep Length,Lower Extremities,and Stature?, ,

A probable correlation between stature and footstep length is expected, and consequently, the stature may be estimated from footstep length. The present research was conducted to study the correlation of footstep length with length of the lower extremities and stature. The study participants (n = 142) were asked to walk on a paper sheet with inked feet and footstep length was measured. Mean stature and lower limb length were significantly larger in males. Sex differences were not observed in the average footstep length. Average footstep length and lower limb length did not show a significant correlation among the participants. A statistically significant correlation was observed between average footstep length and stature only among females. Our observations suggest that the length of the lower limb may not be a major factor in determining the footstep length of a person and that the forensic utility of stature estimation from footstep length may be limited.     

Comparative analysis of 1-phenyl-2-propanone (P2P), an amphetamine-type stimulant precursor, using stable isotope ratio mass spectrometry: Presented in part as a poster at the 2nd meeting of the Joint European Stable Isotope User Meeting (JESIUM), Giens, France, September 2008

The isotope ratios of amphetamine type stimulants (ATS) depend as well on the precursor as the synthetic pathway. For clandestine production of amphetamine and methamphetamine, 1-phenyl-2-propanone (P2P, benzylmethylketone) is a commonly used precursor.Our aim was to determine the variation of the isotope ratios within precursor samples of one manufacturer and to compare seized samples of unknown sources to these values. δ¹³C_V-PDB, δ²H_V-SMOW and δ¹⁸O_V-SMOW isotope ratios were determined using elemental analysis (EA) and gas chromatography (GC) coupled to an isotope ratio mass spectrometer (IRMS). The comparison of all seized samples to the data of the samples of one manufacturer revealed considerable differences. The results show that IRMS provides a high potential in differentiating between precursors from different manufacturers for the clandestine production of ATS and identifying corresponding sources.     

idPAD: Paper Analytical Device for Presumptive Identification of Illicit Drugs

As drug overdose deaths across the United States continue to rise, there is increasing interest in field testing of illicit substances. This work discusses a paper-based analytical device (idPAD) that can run a library of 12 colorimetric tests at the same time, each detecting different chemical functional groups and materials found in illicit drugs, distractor substances, and cutting agents. The idPAD requires no electricity, costs less than $2 USD, and requires minimal training to operate. The results of the 12 tests form a color barcode which is “read” by comparison to standard images. The accuracy of the idPAD was assessed using samples of heroin, cocaine HCl, crack, and methamphetamine at concentrations of 25%–100% in a lactose matrix, as well as pure lactose. Based on 840 “reads” by three different users, the idPAD showed 95% sensitivity and 100% specificity for detecting these drugs; the most common error was mistaking cocaine HCl for crack or crack for cocaine HCl. In a second step, samples of heroin, cocaine, and methamphetamine (n = 30) and distractor substances (pharmaceuticals, cutting agents, and other illicit drugs, n = 64) were tested by two readers, yielding a sensitivity of 100% and specificity of 97%. Targeted substances were detected reliably at 55–180 μg/lane, and the idPAD was found to be stable for at least 3 months when stored at room temperature. The library approach used in the idPAD may provide the accuracy and robustness necessary for a presumptive field drug test.     

Can Stable Isotopes and Radiocarbon Dating Provide a Forensic Solution for Curbing Illegal Harvesting of Threatened Cycads?

Cycads in South Africa are facing an extinction crisis due to the illegal extraction of plants from the wild. Proving wild origin of suspect ex situ cycads to the satisfaction of a court of law is difficult, limiting law enforcement efforts. We investigated the feasibility of using multiple stable isotopes to identify specimens removed from the wild. Relocated and wild specimens from two species in the African genus Encephalartos (E. lebomboensis and E. arenarius) were sampled. ¹⁴C analysis indicated that a ± 30‐year chronology could be reliably obtained from the cycads. For E. arenarius, pre‐relocation tissue was consistent with a wild origin, whereas tissue grown post‐relocation was isotopically distinct from the wild for ⁸⁷Sr/⁸⁶Sr and δ¹⁵N. For E. lebomboensis, δ³⁴S, δ¹⁸O, and ⁸⁷Sr/⁸⁶Sr were different between relocated and control plants, consistent with the >30 years since relocation. Our findings demonstrate the potential for a forensic isotope approach to identify illegal ex situ cycads.     

Psychopathic Personality Traits and Delinquent and Risky Sexual Behaviors in Croatian Sample of Non-referred Boys and Girls

The current study investigated the association of psychopathic traits with violent and non-violent delinquency, delinquency versatility, and risky sexual behavior in Croatian sample of non-referred boys (n = 226) and girls (n = 480). Psychopathic traits were measured by the self-report Youth Psychopathic Traits Inventory (YPI). Consistent with the study’s hypotheses, Impulsive-Irresponsible and Callous-Unemotional dimensions were most consistently associated with all outcome measures. Results of the regression analyses showed that the Impulsive-Irresponsible behavioral style had stronger association with non-violent delinquency and delinquency versatility for boys. However, the Impulsive-Irresponsible dimension had stronger influence on risky sexual behavior for girls compared with boys. The results of a two-group confirmatory factor analysis revealed that the three-factor model of the YPI was invariant across gender.     

Drunk and dangerous: a randomised controlled trial of alcohol brief intervention for violent offenders

To assess the effectiveness of an alcohol brief intervention administered to violent offenders in a judicial (Magistrates’ court) setting, a randomised controlled trial was conducted. Participants (n = 269) were men aged 16–35 years, who resided within a 30-mile radius of Cardiff, UK, and who had been sentenced for a violent offence committed whilst intoxicated with alcohol. Recruitment occurred on-site. Participants were randomly allocated to receive an alcohol brief intervention (n = 135) or to a control group (n = 134). Objective measures comprised re-offending and injury rates. Self-reported outcome measures comprised Alcohol Use Disorders Identification Test (AUDIT); number of drinking days in the past 3 months; total weekly standard units of alcohol; and stage of change with respect to alcohol consumption (as measured by the Readiness to Change Questionnaire). Participants were followed up 3 months (n = 234; 87%) and 12 months (n = 202; 75.1%) after sentence. No significant between-group differences were observed in any of the alcohol measures or in re-offending. Injury was significantly less likely in offenders who had received the intervention (27.4%) than those who had not [39.6%; 95% confidence interval (CI) = −0.23, −0.009]. At 3-month follow-up, significantly more participants in the intervention group (31%; n = 37) than control group (16%; n = 18) demonstrated an increase in their readiness to change drinking behaviour (χ² = 8.56; df = 2; P = 0.014), but this did not persist at 12-month follow-up.

Validation of an LC–MS Method for the Detection and Quantification of BZP and TFMPP and their Hydroxylated Metabolites in Human Plasma and its Application to the Pharmacokinetic Study of TFMPP in Humans*

Abstract: An LC–MS method was developed for benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP), constituents of “party pills” or “legal herbal highs,” and their metabolites in human blood plasma. Compounds were resolved using a mixture of ammonium formate (pH 4.5, 0.01 M) and acetonitrile (flow rate of 1.0 mL/min) with a C18 column. Calibration curves were linear from 1 to 50 ng/mL (R² > 0.99); the lower limit of quantification (LLOQ) was 5 ng/mL; the accuracy was >90%; the intra‐ and interday relative standard deviations (R.S.D) were <5% and <10%, respectively. Human plasma concentrations of TFMPP were measured in blood samples taken from healthy adults (n = 6) over 24 h following a 60‐mg oral dose of TFMPP: these peaked at 24.10 ng/mL (±1.8 ng/mL) (C_max) after 90 min (T_max). Plasma concentrations of 1‐(3‐trifluoromethyl‐4‐hydroxyphenyl) piperazine peaked at 20.2 ng/mL (±4.6 ng/mL) after 90 min. TFMPP had two disposition phases (t_½ = 2.04 h (±0.19 h) and 5.95 h (±1.63 h). Apparent clearance (Cl/F) was 384 L/h (±45 L/h).     

Lessons learned from inter-laboratory studies of carbon isotope analysis of honey

Forensic application of carbon isotope ratio measurements of honey and honey protein to investigate the degree of adulteration with high fructose corn syrup or other C₄ plant sugars is well established. These measurements must use methods that exhibit suitable performance criteria, particularly with regard to measurement uncertainty and traceability – low levels of adulteration can only be detected by methods that result in suitably small measurement uncertainties such that differences of 1‰ or less can be reliably detected. Inter-laboratory exercises are invaluable to assess the state-of-the art of measurement capabilities of laboratories necessary to achieve such performance criteria. National and designated metrology institutes from a number of countries recently participated in an inter-laboratory assessment (CCQM-K140) of stable carbon isotope ratio determination of bulk honey. The same sample material was distributed to a number of forensic isotope analysis laboratories that could not participate directly in the metrological comparison. The results from these studies have demonstrated that the majority of participants provided isotope delta values with acceptable performance metrics; that all participants ensured traceability of their results; and that where measurement uncertainties were reported; these were fit-for-purpose. A number of the forensic laboratories only reported precision rather than full estimates of measurement uncertainty and this was the major cause of the few instances of questionable performance metrics. Reporting of standard deviations in place of measurement uncertainties is common practice outside metrology institutes and the implications for interpretations of small differences in isotopic compositions are discussed. The results have also highlighted a number of considerations that are useful for organisers of similar inter-laboratory studies in the future.     

Homicide by a Forensic Female Sample in Brazil: A Preliminary Study

The objective of the study was to evaluate the mental status of all women (n = 14) who were acquitted by reason of insanity of charges of murder or attempted murder and committed to a forensic psychiatric hospital in the state of Rio de Janeiro, Brazil. All cases were retrospectively examined, including medical files, technical records, and forensic experts' official reports. A conclusive psychiatric diagnosis was established using the Structured Clinical Interview for DSM‐IV Axis I and II Disorders and clinical and forensic records. The most common diagnosis was schizophrenia/schizoaffective disorders (n = 8; 57.3%). Most victims (n = 12; 75%) were close relatives of the patients. We found that 43% (n = 6) of the patients had a previous history of violent behavior. According to the initial psychiatric forensic evaluation, 5 patients (35.7%) had psychotic symptoms. It is expected that a growing understanding of motivational factors underlying homicidal behavior in mentally disturbed female offenders may further the implementation of effective preventive and therapeutic interventions.     

Stature Estimation from Various Foot Dimensions Among Slovak Population

The foot measurements are important in forensic field as they can be used as body height predictors for an individual. The morphology of human feet shows the variations and therefore the aim of this study was to find the relation between stature and foot measurements and to generate population‐specific equations. We measured the stature and bilateral foot measurements of 71 volunteers ranging in age between 18 and 27 years using standard measurements technique. The results revealed nonsignificant bilateral differences in all sex groups (p < 0.05). Sex differences were found to be significant in all foot measurements (p < 0.001). The highest significant and positive correlation coefficients with stature were observed for foot length in males (r = 0.759), in females (r = 0.722), and in the sex‐mixed group (r = 0.865). According to the nonsignificant sex effects on the relation between stature and foot dimensions, the regression equations were computed only for the pooled mixed‐sex group. Our study provides equations that can help to estimate stature from foot measurements among Slovaks.     

Repetitive TASER X26 Discharge Resulted in Adverse Physiologic Events with a Dose–Response Relationship Related to the Duration of Discharge in Anesthetized Swine Model

The objectives of our study were to investigate the dose–response relationship of the TASER X26 discharge duration in an anesthetized swine model. Fourteen swines were anesthetized and then exposed to TASER X26 discharge for 5 sec (n = 5) or for 10 sec (n = 6). The sham control group (n = 3) was anesthetized and studied using the same protocol except TASER X26 discharges during the experiments. Hemodynamic parameters were obtained. Blood pressure and total peripheral resistance decreased significantly after TASER discharge and returned to baseline value at 15 min after 5 sec of TASER discharge but did not return to baseline values during the 30‐min observation period after 10 sec of TASER discharge. Repetitive TASER X26 discharge resulted in adverse physiologic events with a dose–response relationship related to the duration of TASER X26 discharge in an anesthetized swine model.