Journal of Forensic Sciences

Published by Wiley

Online ISSN: 1556-4029


Print ISSN: 0022-1198


Gas chromatography/mass spectrometry for the determination of cocaine and benzoylecgonine over a wide concentration range (<0.005-5 mg/dL) in postmortem blood
  • Article

February 1994


104 Reads

Michael R. Corburt


The determination of cocaine and benzoylecgonine in blood by gas chromatography/mass spectrometry using selected ion monitoring was investigated. The method involved an extraction using rotation of an Amberlite XAD-2-blood mixture and the use of deuterated internal standards with derivatization of benzoylecgonine using diazopropane. Standard curves with logarithmic-transformed data were constructed over the concentration range from 0.005 to 5 mg/dL. The use of a wide concentration range precludes using smaller sample sizes in repeated extractions to conform to a narrower concentration range of standards. The recovery of the extraction method was 85% for both cocaine and benzoylecgonine. The method was applied primarily to postmortem blood samples from 180 forensic cases and was statistically evaluated. The limit of detection for cocaine or benzoylecgonine extractions from 1 mL forensic blood samples is 0.00025 mg/dL. The method is routinely reliable and applicable to forensic toxicology investigations.

The Crash of LOT Flight 007: Dental Identification

December 2002


150 Reads

The authors record the contribution of dentistry to the identification of American victims of one of the most significant aircraft tragedies involving American athletes-the March 1980 crash of a Soviet-made Ilyushin 62 Polish jetliner and the deaths of 31 Americans including a 22-member U.S. amateur boxing team with several U.S. Olympic team candidates. Preparedness was a factor in the dental team's ability to resolve many notable and unexpected problems. Jurisdictional restraints that Polish authorities imposed on the U.S. investigative team hindered its efforts to identify American passengers. The team used dental and fingerprint methods of identification whenever possible and obtained further evidence from anthropologic methods, visual recognition, and personal effects. Dental readiness, organization, methodology, and lessons learned are documented in this paper.

Considerations on the ASTM Standards 1789-04 and 1422-05 on the Forensic Examination of Ink

September 2010


443 Reads

The ASTM standards on Writing Ink Identification (ASTM 1789-04) and on Writing Ink Comparison (ASTM 1422-05) are the most up-to-date guidelines that have been published on the forensic analysis of ink. The aim of these documents is to cover most aspects of the forensic analysis of ink evidence, from the analysis of ink samples, the comparison of the analytical profile of these samples (with the aim to differentiate them or not), through to the interpretation of the result of the examination of these samples in a forensic context. Significant evolutions in the technology available to forensic scientists, in the quality assurance requirements brought onto them, and in the understanding of frameworks to interpret forensic evidence have been made in recent years. This article reviews the two standards in the light of these evolutions and proposes some practical improvements in terms of the standardization of the analyses, the comparison of ink samples, and the interpretation of ink examination. Some of these suggestions have already been included in a DHS funded project aimed at creating a digital ink library for the United States Secret Service.

Sudden Death Caused by 1,1-difluoroethane Inhalation

June 2004


1,775 Reads

A 20-year-old man was found dead on the floor next to a computer, with a nearly full can of "CRC Duster" dust remover located next to the deceased on the floor, and an empty can of the same product on the computer desk. Toxicologic evaluation using either gas chromatography/mass spectrometry (GC/MS) or gas chromatography/flame ionization detector (GC/FID) method identified the active ingredient 1,1-difluoroethane (Freon 152a) in all tissues analyzed. Tissue distribution studies revealed highest concentration in central blood, lung, and liver. It is believed that the 1,1-difluoroethane inhalation was the cause of death.

Evaluation of 1,2-Indanedione and 5,6-Dimethoxy-1,2-Indanedione for the Detection of Latent Fingerprints on Porous Surfaces

August 2000


465 Reads

The ability of 1,2-indanedione and 5,6-dimethoxy-1,2-indanedione to detect latent prints on porous surfaces, as compared to DFO and ninhydrin, has been evaluated. Comparisons of prints developed under various conditions determined the optimum development conditions for the new reagents. The indanediones tested were found to have lower detection limits for glycine. The carrier solvent used was found to affect the quality of the prints developed. In Arklone, the new reagents developed prints that displayed superior luminescence to those developed with DFO. In HFE 7100, 1,2-indanedione and 5,6-dimethoxy-1,2-indanedione gave superior luminescence to DFO after zinc salt treatment and cooling with liquid nitrogen, both of which improve the luminescence of prints developed with 1,2-indanediones. 1,2-Indanediones could offer less expensive but effective alternatives to DFO. With further optimization, the new reagents may supersede DFO as the method of choice for the detection of latent fingerprints on porous surfaces.

Chemical development of latent fingertips: 1,2-indanedoine has come of age

October 2001


966 Reads

The performance of 1,2-indanedione as a latent fingerprint reagent on some types of paper was found to exceed that of DFO, the leading fluorogenic fingerprint reagent. It even exceeds the performance of the sequence, DFO, followed by ninhydrin. No new prints could be observed when ninhydrin was applied after indanedione. On a large number of actual exhibits (used checks) indanedione developed 46% more identifiable prints than the sequence DFO-ninhydrin. A standard procedure for fingerprint development by indanedione is proposed. Best results are obtained with a 0.2% indanedione solution in HFE7100 solvent containing 7% ethyl acetate, but no acetic acid. It can be recommended to start using 1,2-indanedione, which is already commercially available, in actual fingerprint casework.

Use of an Optimized 1,2-Indanedione Process for the Development of Latent Prints*

September 2008


542 Reads

1,2-Indanedione belongs to a class of compounds which have demonstrated great potential in the processing of latent prints, particularly in the area of fluorescence. However, variability in results achieved worldwide has precluded it from being used extensively. In order to isolate the cause of this variability, various components of the formulation were analyzed, including purity level of the indanedione, type of carrier solvent, and the use of ZnCl(2) both as a secondary application and incorporated into the reagent. Using a resultant optimized formulation (Ind-Zn), performance comparisons were then made in the areas of visible color development, fluorescence, and degree of substrate staining with those of 1,8-diazafluoren-9-one (DFO) for both fresh and aged prints. Moisture content of the paper substrates on which the prints had been deposited was measured and a correlation found with percentage ambient relative humidity (% RH). Determination of visible color and fluorescence as it corresponded to percentage moisture content allowed for defining critical threshold levels necessary for achieving optimal results. Correlating these values with % RH then allowed for the development of standard operating procedures for obtaining best possible print development. Through this work, it was determined that a 7.4% v/v formulation of Ind-Zn having petroleum ether as a carrier solvent yielded the most optimal results when processing methods optimized for % RH in the laboratory were utilized. Both initial color development and fluorescence were superior to that of DFO; prints developed with Ind-Zn were a minimum of 6.5 units dE* darker and more red than with DFO for all substrates tested. Processing with Ind-Zn on the majority of the substrates examined yielded fluorescence intensity values approximately four times greater than with DFO.

1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine (MPTP): One Designer Drug and Serendipity

April 1988


28 Reads

Through an unlikely series of coincidences and fortunate accidents, the development of Parkinson's disease in several illicit drug users was traced to their use of a meperidine analog contaminated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The discovery of a chemical capable of producing animal models of the disease has revitalized research efforts and resulted in important new information. The serendipitous finding also prompted consideration of what changes seem advisable if designer drugs are to be dealt with more efficaciously.

1,2,4-Triazine-Based Chromogenic Reagents for the Detection of Microtraces of Various Metals Left on Human Skin

March 2010


91 Reads

This article extends the application of 1,2,4-triazine-based chromogenic reagents to the detection of nonferrous metal traces left on contact with canvas and human skin. The possibility of detection of iron traces resulting from contact with objects made of stainless steel was investigated as well. Additionally, the ability of triazines to form chromatic complexes with Zn(2+), Ni(2+), Co(2+), Cu(2+), Cr(3+), and Al(3+) ions was studied spectrophotometrically. Molar absorption coefficients, ranging from 8.8 to 29.9 x 10(3)/M/cm, provide high sensitivity of 1,2,4-triazines toward nonferrous ions, thus, enabling the detection at concentrations as low as a few muM. The method was sensitive enough to detect traces resulting from a 1-min contact with a stainless steel made object, which is commonly considered as a corrosion-resistant material. The amounts of metal ions transferred to the skin after a 2-min contact with objects made of brass, zinc, and copper were sufficient to develop chromatic imprints.

Formation of an Interfering Substance, 3,4-Dimethyl-5 - Phenyl 1,3 - Oxazolidine, During A Pseudoephedrine Urinalysis.

August 2000


399 Reads






During fatal aviation accident investigations, biosamples from the victims are submitted to the FAA Civil Aeromedical Institute (CAMI) for drug analysis. In the process of one such analysis by CAMI, an unknown substance was found in a urine sample. Simultaneous screening by thin layer chromatography (TLC) and gas chromatography/FID (GC/FID) suggested the presence of pseudoephedrine. A subsequent routine confirmation analysis of a separate urine aliquot by GC Fourier transform infrared (GC/FTIR) and GC mass spectrometry (GC/MS) indicated that the retention times of the unknown substance matched with those of pseudoephedrine. However, its infrared and mass spectra were different--the -OH and -NH groups were missing, a C-O-C group was present, and the molar mass was 12 atomic mass units (amu) more than that of pseudoephedrine. A subsequent literature search suggested that ephedrine-like amines react with aldehydes to form oxazolidines. Therefore, the 12-amu increase could be accounted for by condensation of pseudoephedrine with formaldehyde. Since this aldehyde is present in various grades of methanol and ethyl acetate, and these solvents were used during the solid-phase extraction, 3,4-dimethyl-5-phenyl-1,3-oxazolidine was synthesized by using (+)-pseudoephedrine HCl and formaldehyde. The analytical findings of the synthesized compound were consistent with those of the unknown interfering substance, confirming that it was the oxazolidine. Aldehyde contaminants in solvents or specimens can transform drugs of interest and may result in misidentification of a compound originally present in specimens. Therefore, chemicals used in analyses should be of the highest available purity, and a multi-analytical approach should be adopted to maintain a high degree of quality assurance.

Latent Fingermark Development on a Range of Porous Substrates Using Ninhydrin Analogs-A Comparison with Ninhydrin and 1,8-Diazofluoren

November 2011


181 Reads

Three relatively new reagents for developing latent fingermarks on porous substrates, 1,2-indandione (IND), 5-methylthioninhydrin (5-MTN), and lawsone, are compared with the more widely used ninhydrin and 1,8-diazofluoren (DFO). Developed latent fingermark visualization on 10 different substrates comprising colored papers, cardboard, and cellophane rather than conventional printer and writing/notepad paper is assessed using latent fingermark deposits from 48 donors. Results show improved fluorescent fingermark visualization using IND compared with DFO on a range of colored cardboards and thick white paper, thus extending the range of substrates known to yield improved visualization with IND. Adding zinc chloride to IND failed to yield any further improvement in fluorescent fingermark visualization. 5-MTN (with and without zinc chloride posttreatment) showed no improvement in visualization compared with ninhydrin and DFO although visible fingermarks were developed. Lawsone produced fluorescent visible fingermarks only with white substrates, which were inferior to those produced with DFO.

Analysis and interpretation of the HLA DQ alpha "1.1 weak-signal" observed during the PCR-based typing method

February 1994


17 Reads

The Perkin-Elmer (PE) AmpliType DQ alpha Forensic Kit is currently available for amplification and typing of a polymorphic region in the Human Leukocyte Antigen (HLA) DQ alpha DNA sequence. Following amplification of the DQ alpha region with the PE kit, typing strips are processed. These strips contain immobilized DNA probes designed to distinguish six possible HLA DQ alpha alleles. It has been observed in this laboratory and others that in a single source DNA sample, it is possible to detect a weak signal on the 1.1 specific allele dot when the samples' genotype clearly does not contain the 1.1 allele. It has been suggested that a potential source of this weak-signal is the non-specific amplification of a HLA DX alpha gene sequence. To demonstrate the relationship of the DX alpha gene to the 1.1 nonspecific signal, we designed biotinylated DX alpha PCR primers specific for a 178 bp region in which the amplified product spans the homologous DQ alpha region encompassing the DNA probes present on the typing strips. DX alpha DNA sequences from various DQ alpha genotypes were amplified and hybridized to DQ alpha typing strips. We have demonstrated that DX alpha PCR products do not always hybridize to the 1.1 probe on the typing strips. Sequence analysis of DX alpha PCR products show that this region is polymorphic which may explain why the occurrence of the "1.1 weak-signal" is unpredictable. We have further analyzed the effect of DNA template concentration for the DQ alpha amplification protocol and have shown that regulation of PCR input DNA optimizes the amplification and typing protocols for HLA DQ alpha alleles and minimizes the potential observation of the "1.1 weak-signal."

Detection of a Primer-Binding Site Polymorphism for the STR Locus D16S539 Using the Powerplex ® 1.1 System and Validation of a Degenerate Primer to Correct for the Polymorphism

April 2002


292 Reads

Quality assurance samples submitted from the NCSBI as part of a contract with TBTG to outsource DNA Database samples showed unexpected discrepancies for the locus D16S539 when all other loci yielded identical results. Discrepancies observed included allele drop out and an imbalance in sister alleles with samples returned from TBTG. This led to a comprehensive review of the technical procedures used between the two laboratories to determine the cause of the discrepancies noted for the locus D16S539, since both laboratories were using the PowerPlex 1.1 typing kit from the Promega Corporation. The NCSBI and the TBTG utilize different extraction methods (organic extraction vs. FTA) and amplification conditions (AmpliTaq vs AmpliTaq Gold), respectively, so the exact cause of discrepancy observed was not immediately apparent. Experiments at the NCSBI associated the observed allele drop out and the imbalance of the sister alleles with the use of AmpliTaq Gold and a hot start procedure. Sequencing data revealed that a point mutation resides on the D16S539 primer-binding site that reaches polymorphic levels in African-American populations. This led to the development of a degenerate primer by the Promega Corporation to detect "missing" alleles when AmpliTaq Gold is used. The degenerate primer was then thoroughly tested to show its efficacy in detecting the "true" D16S539 profile when used.

Validation of the PowerPlex 1.1(TM) loci for use in human identification

June 2000


79 Reads

STR typing is now the favored method of DNA analysis for the purposes of human identification in the forensic community. The Forensic Services Division of the Detroit Police Department has completed its validation of the PowerPlex 1.1 loci (CSF1PO, TPOX, THO1, vWA, D16S539, D7S820, D13S317, and D5S818) for use in forensic casework. Detroit Metro Area Red Cross samples were typed from each of five racial/ethnic groups--the Hispanic, Caucasian, African American, Asian, and American Indian populations--and allele and genotype frequencies were calculated. A rare off-ladder variant (9.1 allele at D7S820) was identified among the database samples. A number of validation studies were performed. DNA was extracted from different substrates and typed as expected, except for the DNA extracted from leather (signal absent from the D16S539, D7S820, D13S317, CSF1PO, and TPOX loci) and from dirt (no PCR product generated). The minor contributor in the mixture study (250 pg input DNA) was facile to discern. The Concordance study, the variety of fluids from the same individual, and NIST standards studies all produced the expected results. Finally, STR data confirmed previous DNA typing results from adjudicated casework samples.

Uruguayan Population Data for Eight STR Loci (Using the PowerPlex 1.2™ Kit)
  • Article
  • Full-text available

February 2001


55 Reads


An In Vitro Study of the Accuracy and Precision of Breathalyzer® Models 900, 900A, and 1000

November 1985


37 Reads

Ninety Breathalyzer instruments (Model 1000) and twenty instruments (Models 900, 900A) were studied using a protocol described by the Department of Transportation's "Standard for Devices to Measure Breath Alcohol." Although the mean of each of three concentrations tested (0.05, 0.10, and 0.15 g/210 L) compared favorably in both series, the standard deviation was consistently higher for the Model 1000 instruments. The Model 1000 instruments also produced a significant number of test results which exceeded the normally expected scientific deviation.

Natural Death as Viewed by the Medical Examiner: A Review of 1000 Consecutive Autopsies of Individuals Dying of Natural Disease

February 1991


39 Reads

A study of 1000 consecutive autopsies of individuals dying of natural disease was conducted. Cardiovascular disease was responsible for 60.9% of all deaths with coronary artery disease--not only the main cause of cardiovascular death but also the main cause of all natural deaths--accounting for 45.1% of such cases. Diseases of the central nervous and respiratory systems accounted for 8.7 and 8.6%, respectively, of the natural deaths. Seizure disorders and pneumonia were the main causes of death in these organ systems. There were 124 deaths of children less than one year in age, 91 of which were due to sudden infant death syndrome (SIDS). All of the SIDS deaths were in children less than 10 months old.

Anatomical Location of Bitemarks and Associated Findings in 101 Cases from the United States

August 2000


669 Reads

The purpose of this paper is to update and confirm previous studies that examined the anatomical location of human bitemarks. This information is useful to forensic odontologists and pathologists, physicians, and coroners who must be familiar with the most likely locations of bitemarks. The data are also useful for those involved in bitemark research. Using the legal database "Lexis," 101 bitemark cases were identified from the United States Courts of Appeal. Cases were included in the study if they provided details concerning the bitemark, such as anatomical location, number of injuries, and information concerning the victim. Information on 148 bites was collated. These data are presented in tabular and graphical form to allow comparisons between males and females, victims and perpetrators, adults and children, and the crime types associated with human bites.

Fungal tunneling of hair from a buried body. J Forensic Sci 37(4): 1048-1054

August 1992


231 Reads

Tunnels produced in human head hair by fungal hyphae were examined with a light microscope and with a scanning electron microscope. The tunnels had small diameters and exhibited minimal branching. The use of a backscattered electron detector facilitated the locating of the openings of the tunnels in the surfaces of the hairs. In the backscattered electron image, tunnel openings appeared as dark spots. The tunneling hyphae did not show a preference for a particular location for entering the shaft of the hair. Some hyphae penetrated under the free edges of the cuticular scales, while others burrowed through the surfaces of the scales.

Investigation of a murder case involving arson. J Forensic Sci 41, 1064 - 1067

December 1996


33 Reads

In some religious societies, the value of life seems to be different from that in western nonreligious societies. Violating the family honor could result in killing. This article presents a case in which a Moslem Israeli citizen killed his daughter. Professional field work, together with forensic laboratory examinations, led to life imprisonment of the father.

Observed Characteristics of Suicidal Hangings: An 11-year Retrospective Review

July 2012


118 Reads

Many studies have been published regarding suicidal hanging deaths, and most forensic pathologists and coroners are very familiar with such causes of death. Forensic pathologists are challenged over their rulings regarding manner of death in part because the general public has a limited scope of knowledge. One such challenge centers on the question of whether a hanging can be a suicide if the individual is not fully suspended. The authors designed a retrospective study to review suspension in hangings and to analyze other criteria used to help in deciding manner of death. We examined 229 suicidal hanging deaths over an 11-year period (1997 through early 2009) using the data from two separate jurisdictions in Ohio. In conclusion, we found that the vast majority (83.4%) of people who hanged themselves were found partially suspended. Among other criteria analyzed, only the presence of petechial hemorrhages and acute neck injury was statistically significant.

A Fatal Case of Trichlorofluoromethane (Freon 11) Poisoning. Tissue Distribution Study by Gas Chromatography-Mass Spectrometry

June 1994


99 Reads

A case of lethal poisoning due to trichlorofluoromethane (FC11) inhalation is described. The fluorocarbon was determined in biological tissues by headspace gas chromatography-mass spectrometry. FC11 was detected in all the examined tissues, with decreasing levels in heart, lung, brain, liver, blood, kidney, and spleen. The highest concentration measured in heart could be related to the mode of toxic action of fluorocarbons postulated by many authors, characterized by the sensitization of the myocardium to the catecholamines producing arrhythmia and cardiac arrest. Nevertheless the aspecific picture of the anatomo-pathological and histological findings does not exclude that the described accidental fatality may have been caused by the combination of direct from toxicity with hypoxemic asphyxiation, due to the saturation of the atmosphere by FC11 in the closed environment in which the intoxication occurred.

An Indoor Air Quality-Pharmacokinetic Simulation of Passive Inhalation of Marijuana Smoke and the Resultant Buildup of 11-Nor-Delta-9-Tetrahydrocannabinol-9-Carboxylic Acid in Urine

April 1997


40 Reads

In military courts of law, the good soldier defense is often used by the defendant to explain the presence of 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid in urine (hereafter referred to as THCA) above the Department of Defense (DOD) established limit of 15 ng/mL. The defense will contend the defendant unwittingly breathed side-stream marijuana smoke, thus resulting in the presence of THCA in the defendant's urine. The purpose of this work was to link an indoor air quality model (IAQ) with a pharmacokinetic (PK) model to predict a passive marijuana smoker's resultant concentration of the major urinary metabolite THCA.

Use of Styryl 11 and STaR 11 for the Luminescence Enhancement of Cyanoacrylate-Developed Fingermarks in the Visible and Near-Infrared Regions

July 2011


99 Reads

In current casework, most post-cyanoacrylate stains rely on luminescence emission in the visible region (400-700 nm). While traditional stains such as rhodamine 6G work well under most circumstances, some surfaces may generate background luminescence under the same conditions. Detection in the near-infrared region (NIR > 700 nm) has shown to be effective in minimizing the interferences from such surfaces. The laser dye styryl 11 generated strongly luminescent fingermarks when applied after cyanoacrylate fuming on all surfaces tested. When compared to rhodamine 6G, the dye was superior only when viewed in the NIR. Styryl 11 was subsequently combined with rhodamine 6G, and the mixed stain formulation (named StaR 11 by the authors) induced stronger luminescence compared with styryl 11 alone with an ability to visualize in both the visible and NIR regions. Reliable and consistent results were obtained when using either styryl 11 alone or the STaR 11 mixture. The enhancement achieved did not otherwise vary depending on the source of the fingermark secretions. With visualization possible in both the visible and NIR regions, the styryl 11/rhodamine 6G mixture showed significant potential as a post-cyanoacrylate stain.

Studies on the Stability and Detection of Cocaine, Benzoylecgonine, and 11-Nor-Delta-9-Tetrahydrocannabinol-9-Carboxylic Acid in Whole Blood Using Abuscreen® Radioimmunoassay

August 1989


175 Reads

A study was undertaken to assess the stability and the radioimmunoassay (RIA) detection of cocaine, benzoylecgonine (BZE), and 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in whole blood while stored in 4 different kinds of blood collection tubes for up to 30 days at refrigeration and room temperatures. At various intervals, the tubes were sampled and analyzed using Abuscreen RIA. Also, semi-quantitative data derived from RIA analysis of forensic blood specimens were compared with quantitative data acquired using gas chromatography (GC) or GC/mass spectrometry (GC/MS) on the same specimens. RIA and chromatographic studies revealed that BZE and THC-COOH were stable in blood under all conditions studied. Cocaine, however, was found not to be stable in blood, especially when stored at room temperatures. Despite cocaine's instability in blood, RIA was able to detect the presence of cocaine and its breakdown products in blood under all conditions studied.

Development and Validation of a Simple GC-MS Method for the Simultaneous Determination of 11 Anticholinesterase Pesticides in Blood-Clinical and Forensic Toxicology Applications

January 2012


195 Reads

Anticholinesterase pesticides are widely used, and as a result they are involved in numerous acute and even fatal poisonings. The aim of this study was the development, optimization, and validation of a simple, rapid, specific, and sensitive gas chromatography-mass spectrometry method for the determination of 11 anticholinesterase pesticides (aldicarb, azinphos methyl, carbofuran, chlorpyrifos, dialifos, diazinon, malathion, methamidophos, methidathion, methomyl, and terbufos) in blood. Only 500 μL of blood was used, and the recoveries after liquid-liquid extraction (toluene/chloroform, 4:1, v/v) were more than 65.6%. The calibration curves were linear (R(2) ≥ 0.996). Limit of detections and limit of quantifications were found to be between 1.00-10.0 and 3.00-30.0 μg/L, respectively. Accuracy expressed as the %E(r) was found to be between -11.0 and 7.8%. Precision expressed as the percent relative standard deviation was found to be <9.4%. The developed method can be applied for the investigation of both forensic and clinical cases of accidental or suicidal poisoning with these pesticides.

Utility of the Y-STR typing systems Y-PLEX™ 6 and Y-PLEX™ 5 in forensic casework and 11 Y-STR haplotype database for three major population groups in the United States

August 2004


72 Reads

The Y-PLEX 6 and Y-PLEX 5 systems enable analysis for 11 Y-STR loci. We present here the utility of these systems in forensic casework. A total of 188 samples, including 127 evidence samples, were analyzed using either or both of the systems. The evidence sample types included fingernail scrapings, sperm or seminal fluid, epithelial cells, blood and other tissues. The Y-STR typing systems provided useful probative results in difficult cases. A reference database for Caucasian (n = 517), African American (n = 535), and Hispanic (n = 245) population groups within the United States was generated for estimating the haplotype frequency in forensic casework. Among the individuals profiled, 311 Caucasians, 412 African Americans, and 194 Hispanics provided unique profiles in their respective population datasets. This is the first report describing the haplotype database for the set of 11 Y-STR loci recommended by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Linkage analysis reveals that the frequencies from forensically important autosomal loci can be multiplied with the Y-STR haplotype frequency. The results from Y-PLEX systems have been accepted in courts in the United States.

Simultaneous Quantitation of Delta-9-tetrahydrocannabinol (THC) and 11-Nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) in Serum by GC/MS Using Deuterated Internal Standards and Its Application to a Smoking Study and Forensic Cases

August 1992


69 Reads

A new procedure for the simultaneous detection of delta-9-tetrahydrocannabinol (THC) and its major metabolite, 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) in serum has been evaluated. The method combines rapid, efficient, solid-phase extraction and simple derivatization by methylation. Analysis and quantitation is performed by gas chromatography/mass spectrometry (GC/MS) using deuterated cannabinoids as internal standards (IS). Reproducibility and sensitivity of the method are good. The procedure is applied to serum specimens collected from a smoking study with 24 volunteers and 212 forensic cases. Results are interpreted based upon the current knowledge about THC metabolism and pharmacokinetics.

Gm(11) Grouping of Dried Bloodstains

November 1984


22 Reads

An absorption inhibition method for the detection of gamma marker Gm(11) in dried bloodstains is described. Particular reference is made to the association of Gm(11) with Gm(-1, -2). When a dried bloodstain fails to inhibit anti-Gm(1) and anti-Gm(2), this may represent a true Gm(-1, -2) result or there may be insufficient material to inhibit either antibody. The detection of Gm(11) in a bloodstain extract provides an objective means of confirming the apparent absence of Gm(1) and Gm(2) as representing a true Gm(-1, -2) result. This antigen compares very well with other blood group systems with regard to the amount of bloodstain required for analysis and its stability. No evidence is available for preferential loss of Gm(1) and Gm(2) relative to Gm(11) in dried bloodstains.

Solid-Phase Extraction, Identification, and Quantitation of 11-Nor-Delta-9-Tetrahydrocannabinol-9-Carboxylic Acid

August 1990


12 Reads

A procedure has been developed to extract and recover minute amounts of delta-9-carboxytetrahydrocannabinol (THC-COOH) from urine. A new non-isotopic internal standard is introduced to permit a chromatographic assay of the metabolite. The method affords a 91% recovery of 20 ng/mL of the THC-COOH acid from spiked urine with the assurance of a 3.8% coefficient of variation.

Composition of Bacillus Species in Aerosols from 11 U.S. Cities

June 2006


45 Reads

A PCR-based heteroduplex assay was used to determine the presence and composition of Bacillus species in 11,059 Environmental Protection Agency PM2.5 aerosol samples from 11 U.S. cities. The assay differentiated three groups: Type A containing Bacillus anthracis and very closely related, often pathogenic, Bacillus cereus and Bacillus thuringiensis strains; Type B containing other B. cereus and B. thuringiensis strains; and a third group of more-distantly related Bacillus species. Eight of the 11 cities were positive for Bacillus species in 50% or more of the samples, and the percent of aerosol samples that contained the HD Type A group ranged from 3% to 32%. Cities from the eastern half of the United States generally contained a higher frequency and broader diversity of Bacillus species than the western half of the United States. Positive samples were detected throughout the year. These results have implications for pathogen detection in environmental samples, understanding the natural evolution of new pathogenic strains, and incidence of infection caused by strains of the B. cereus subgroup.

Potassium Nitrite Reaction with 11-Nor-Delta9-Tetrahydrocannabinol-9-Carboxylic Acid in Urine in Relation to the Drug Screening Analysis

October 1999


151 Reads

Recently potassium nitrite has been used as an adulterant to interfere with the analysis of 11-nor-delta 9-tetrahydro-cannabinol-9-carboxylic acid (THC-COOH) in urine. A comprehensive study of the THC-COOH and nitrite reaction chemistry and stability under various conditions is presented. Reverse phase high performance liquid chromatography (HPLC) and negative electrospray mass spectrometry (ESMS) results are given to substantiate the derived reaction mechanism and properties leading to reaction termination. The addition of potassium carbonate as a buffering agent prior to or following sample void as a means of preventing the formation of a nitroso-complexed form of the 11-nor-delta 9+-tetrahydrocannabinol-9-carboxylic acid is evaluated.

Genetic Structure Among 38 Populations from the United States Based on 11 U.S. Core Y Chromosome STRs*

June 2006


22 Reads

A DNA database consisting of the 11 Y chromosome short-tandem-repeat (Y-STR) recommended by the Scientific Working Group on DNA Analysis Methods is constructed for 2517 individuals from 38 populations in the United States. The population samples derive from five ethnic groups currently living in 10 states. A multidimensional scaling (MDS) plot places the populations into four discrete clusters (African Americans (AA), European Americans (EA), Hispanic Americans (HA), and Asian Americans (SA)) and one dispersed cluster of Native Americans. An analysis of molecular variance (AMOVA) indicates that a large proportion of the total genetic variance is partitioned among ethnic groups (24.8%), whereas only a small amount (1.5%) is found among-populations within ethnic groups. Separate AMOVA analyses within each ethnic group show that only the NA sample contains statistically significant among-population variation. Pair wise population differentiation tests do uncover heterogeneity among EA and among HA populations; however, this is due to only a single sample within each group. The analyses support the creation of AA, EA, HA, and Asian American databases in which samples from different geographic regions within the United States are pooled. We recommend that separate databases be constructed for different NA groups.

Tolerance at High Blood Alcohol Concentrations: A Study of 110 Cases and Review of the Literature

February 1986


116 Reads

One hundred ten consecutive alcoholics who voluntarily entered a detoxification center were studied to determine their ability to perform certain designated functions (a) while under the influence of alcohol at admission and (b) four days later, after they had undergone detoxification. Their blood alcohol concentrations (BACs) within an hour of admission were determined by using the DuPont Automated Clinical Analyzer (ACA), following standard procedures. The results of the tests performed by these subjects were then studied to ascertain the level of psychomotor impairment in alcoholics at elevated BACs. The results were broken down by age, sex, race, and BAC. The findings indicate that alcoholics develop an increased tolerance to alcohol at BACs, which are extremely high, including levels generally considered to be potentially fatal.

Evaluation of the Abbott TD x -Radiative Energy Attenuation (REA) Ethanol Assay in a Study of 1105 Forensic Whole Blood Specimens

February 1987


27 Reads

In a preliminary study to determine the applicability of the Abbott radiative energy attenuation (REA) method for the quantification of ethanol in whole blood specimens it was concluded that a larger number of samples was required to evaluate the method, particularly for use in forensic toxicology applications. In this study, 573 blood specimens from suspected driving while intoxicated individuals (DWI blood) and 532 postmortem blood specimens (PM blood) were analyzed by the REA method and a headspace gas chromatographic method (GC) currently used in this laboratory. "Negative" specimens (less than 10 mg/dL by GC) and "positive" specimens (greater than or equal to 10 mg/dL by GC) in each category were analyzed. Linear regression analysis comparing the REA values with the GC values was performed for each type of blood specimen. The equation obtained for DWI blood specimens was REA = 0.943 GC + 1.54; the equation for PM blood specimens was REA = 0.980 GC + 2.76. The correlation coefficient for each group was greater than 0.99. The data suggested that a limit of detection of 10 mg/dL could be applied for DWI blood specimens, while 20 mg/dL would be recommended as the limit of detection for PM blood specimens.