A study of illicit cocaine seizure classification by pattern recognition techniques applied to metal data

Fifteen metallic species, silver (Ag), aluminum (Al), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), lead (Pb), strontium (Sr) and zinc (Zn), were determined in 46 cocaine samples confiscated by the Spanish police in Galicia (northwest Spain). Classification of these cocaine samples according to their geographic origin (Colombia and Venezuela) was achieved by the application of pattern recognition techniques to the metallic content data. Cocaine samples, around 0.5 g, were directly dissolved in 2 mL of 35.0% (v/v) HNO3, diluted to 10 mL with ultrapure water. The metals were quantified by means of electrothermal atomic absorption spectrometry (Ag, Al, Cd, Cr, Cu, Mn, Ni, Pb and Sr), flame atomic absorption spectrometry (Ca, Fe, Mg and Zn), and flame atomic emission spectrometry (K and Na). Results show that two geographic origins can be established through the presence of trace and major elements.     

Shotgun shooting in northern India--a review (1980-1999)

Central Forensic Science Laboratory (CFSL), Chandigarh undertakes the examination of the crime cases of some northern states of India. The shooting cases of last two decades (1980-1999) involving shotguns were analysed in this laboratory. This paper consists of the study of 360 actual cases of shotguns for evaluation of various parameters, such as type of firearm, number of firearm and firing, location of wound, age, occupation, sex and caste of accused and victim, etc. Out of 360 cases, 253 (70%) were classified as homicidal, 68 (19%) accidental, 11 (3%) suicidal, 9 (2.5%) hunting and 19 (5.5%) cases of insufficient information including the cases of illegal possession of firearm. Single Barrel Breech Loading (SBBL) gun 144 (40%) was preferred over Single Barrel Muzzle Loading (SBML) 109 (30.3%), Double Barrel Breech Loading (DBBL) 72 (20%) and Double Barrel Muzzle Loading (DBML) gun 35 (9.7%). All the breechloader guns were of 12 bore. Muzzleloader gun were recovered only from the remote rural areas. Three hundred and thirty-one (92%) cases involved single, 22 (6%) double and 7 (2%) more than two shotgun. Majority of cases were found of single firing 288 (80%), followed by double 29 (8%) and multi-firing 18 (5%). Eleven (3%) cases were of misfiring and in 14 (4%) cases information was not available. Accidental and suicidal cases had only one firing. The mean age for male and female victim was 31 and 24 years, respectively. Occupationally, agriculture is predominating over business, service and security guards for accused and for victim agriculture followed by service, business, student and security guards are in the descending order. Caste wise the most aggressive community of Kshatriyas is predominating as accused and victim over lower cast people. Head (64%) being a vital part was chosen most frequently for committing suicide followed by body (36%). Service personnel committed maximum number of suicide.     

USGS42 and USGS43: human-hair stable hydrogen and oxygen isotopic reference materials and analytical methods for forensic science and implications for published measurement results

Because there are no internationally distributed stable hydrogen and oxygen isotopic reference materials of human hair, the U.S. Geological Survey (USGS) has prepared two such materials, USGS42 and USGS43. These reference materials span values commonly encountered in human hair stable isotope analysis and are isotopically homogeneous at sample sizes larger than 0.2 mg. USGS42 and USGS43 human-hair isotopic reference materials are intended for calibration of δ(2)H and δ(18)O measurements of unknown human hair by quantifying (1) drift with time, (2) mass-dependent isotopic fractionation, and (3) isotope-ratio-scale contraction. While they are intended for measurements of the stable isotopes of hydrogen and oxygen, they also are suitable for measurements of the stable isotopes of carbon, nitrogen, and sulfur in human and mammalian hair. Preliminary isotopic compositions of the non-exchangeable fractions of these materials are USGS42(Tibetan hair)δ(2)H(VSMOW-SLAP) = -78.5 ± 2.3‰ (n = 62) and δ(18)O(VSMOW-SLAP) = +8.56 ± 0.10‰ (n = 18) USGS42(Indian hair)δ(2)H(VSMOW-SLAP) = -50.3 ± 2.8‰ (n = 64) and δ(18)O(VSMOW-SLAP) = +14.11 ± 0.10‰ (n = 18). Using recommended analytical protocols presented herein for δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) measurements, the least squares fit regression of 11 human hair reference materials is δ(2)H(VSMOW-SLAP) = 6.085δ(2)O(VSMOW-SLAP) - 136.0‰ with an R-square value of 0.95. The δ(2)H difference between the calibrated results of human hair in this investigation and a commonly accepted human-hair relationship is a remarkable 34‰. It is critical that readers pay attention to the δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) of isotopic reference materials in publications, and they need to adjust the δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) measurement results of human hair in previous publications, as needed, to ensure all results on are on the same scales.     

The changes of fourier transform infrared spectrum in rat brain

Estimation of the time since death (postmortem interval [PMI]) is one of the most difficult problems in forensic investigations, and many methods currently are utilized to estimate the PMI. The goal of this study was to investigate the changes of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra of rat brain from postmortem time 0-144 h. The intensity ratios of major absorbance bands were examined (I(1066)/I(1392), I(1168)/I(1392), I(1234)/I(1454), I(1301)/I(1392), I(1647)/I(2956), I(2921)/I(2850), and I(1647)/I(1539)). The spectra of rat brain displayed prominent changes with increasing PMI. The band at 2871 and 1737 per cm became weak with the time increasing and even disappeared at postmortem 96 and 72 h, respectively. A close linear correlation was shown between the relative absorption intensity and the PMI, and the I(1234) /I(1454) offered a stronger correlation (r = 0.973). Our results indicate that ATR-FTIR spectroscopy may be a useful technique for estimating the PMI.     

Immunocytochemical study on the ultrastructural localization of human-type ABO (H)-blood group activities in a macaque (Macaca irus)

The immunocytochemical study on the ultrastructural localization of human-type ABO(H)-activities in a crab-eating macaque (Macaca irus) was carried out by using postembedding and immuno-gold staining method. The tissue specimens examined were the esophagus, stomach (St), small intestine (Si), large intestine, liver, kidney, and pancreas. The specimens from these organs and submandibular gland (Sg) of a human (O-group) were used as staining reaction controls. Primary and secondary antibodies were commercially obtained mouse monoclonal anti-A, -B, -H (IgM), and goat anti-mouse IgM labeled with colloidal gold particles (luminal diameter 20 nm), respectively. The results were as follows: (1) In macaque specimens, only A-activity could be observed as the location of gold particles on the peripheral rim of serous secretory granules (Sg) and of epithelial cells (esophagus), the mucous droplets in epithelial cells and brush border (St, Si), the intracellular secretory canaliculi [ISC (St)] and the zymogen granules and secretory ducts (pancreas). Gold particles could be also noted at the Golgi apparatus and nascent secretory granules. (2) By periodic acid-thiocarbohydrazide-osmium tetroxide (PA-TCH-OS) reaction, hexose-rich neutral mucopolysaccharides were noted on the peripheral rim of serous secretory granules (Sg), the mucous droplets (St, Si), the ISC (St), and the brush border (Si). Such a distributional pattern corresponded well with that of gold particles, indicating that the substances were responsible for ABO(H)-activities.     

Exemption of certain systems of records under the Privacy Act. Final rule

This final rule exempts four systems of records (SORs) from subsections (c)(3), (d)(1) through (d)(4), (e)(4)(G) and (H), and (f) of the Privacy Act pursuant to 5 U.S.C. 552a(k)(2): The Automated Survey Processing Environment (ASPEN) Complaint/ Incidents Tracking System (ACTS), HHS/CMS, System No. 09-70-0565; the Health Insurance Portability and Accountability Act (HIPAA) Information Tracking System (HITS), HHS/CMS, System No. 09-70-0544; the Organ Procurement Organizations System (OPOS), HHS/CMS, System No. 09-70- 0575; and the Fraud Investigation Database (FID), HHS/CMS, System No. 09-70-0527.     

Concentration of drugs in blood of suspected impaired drivers

Analytical records concerning 440 living drivers suspected of driving under the influence of drug (DUID) were collected and examined during a 2 years period ranging from 2002 to 2003 in canton de Vaud, Valais, Jura and Fribourg (Switzerland). This study included 400 men (91%) and 40 women (9%). The average age of the drivers was 28+/-10 years (minimum 16 and maximum 81). One or more psychoactive drugs were found in 89% of blood samples. Half of cases (223 of 440, 50.7%) involved consumption of mixtures (from 2 to 6) of psychoactive drugs. The most commonly detected drugs in whole blood were cannabinoids (59%), ethanol (46%), benzodiazepines (13%), cocaine (13%), amphetamines (9%), opiates (9%) and methadone (7%). Among these 440 cases, 11-carboxy-THC (THCCOOH) was found in 59% (median 25 ng/ml (1-215 ng/ml)), Delta(9)-tetrahydrocannabinol (THC) in 53% (median 3 ng/ml (1-35 ng/ml)), ethanol in 46% (median 1.19 g/kg (0.14-2.95 g/kg)), benzoylecgonine in 13% (median 250 ng/ml (29-2430 ng/ml)), free morphine in 7% (median 10 ng/ml (1-111 ng/ml)), methadone in 7% (median 110 ng/ml (27-850 ng/ml)), 3,4-methylenedioxymethamphetamine (MDMA) in 6% (median 218 ng/ml (10-2480 ng/ml)), nordiazepam in 5% (median 305 ng/ml (30-1560 ng/ml)), free codeine in 5% (median 5 ng/ml (1-13 ng/ml)), midazolam in 5% (median 44 ng/ml (20-250 ng/ml)), cocaine in 5% (median 50 ng/ml (15-560 ng/ml)), amphetamine in 4% (median 54 ng/ml (10-183 ng/ml)), diazepam in 2% (median 200 ng/ml (80-630 ng/ml)) and oxazepam in 2% (median 230 ng/ml (165-3830 ng/ml)). Other drugs, such as lorazepam, zolpidem, mirtazapine, methaqualone, were found in less than 1% of the cases.     

“法”义新论

"法"在字源和词源上有三个系统,即灋、佱、。许慎在《说文》中仅以战国篆文为据,未能考察商至战国前期文字发展的理路,对"灋"的词源解释有误。廌与作为神兽的獬豸有差异,并无掌法神兽之义。灋字在西周时代作为"废"的本字使用,与后世的"法"义并无关联。宗周文化系统中有一个表规范、法则意义的"佱"字;南方文化中有一个表达规范、法则、效法甚至法律的"",因此在先秦时代有宗周的"佱"和南方的""两个与后世"法"有渊源关系的概念系统。这两个系统在春秋中叶至战国时代发生碰撞、融合,最终以""吸纳并取代"佱",并写作"灋"为终结。具有"刑罚"、"审判"之义的"法",通过"灋"的字源和词源无法解释,而当与宗周文化系统之外的南方文化中的系统有关。     

Age estimation by pulp/tooth ratio in canines by mesial and vestibular peri-apical X-rays

Changes in the size of the pulp canal, caused by apposition of secondary dentine, are the best morphometric parameters for estimating age by X-rays. The apposition of secondary dentine is the most frequently used method for age estimation in adult subjects. In two previous papers, we studied the application of the pulp/tooth area ratio by peri-apical X-rays as an indicator of age at death. The aim of the present study was to test the accuracy of age evaluation by combined analysis of labio-lingual and mesial peri-apical X-rays of lower and upper canines. A total of 200 such X-rays were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio according to labio-lingual and mesial X-rays on upper (x(1), x(2)) and lower (x(3), x(4)) canines. Very good agreement was found between intra-observer measurements. Statistical analysis showed that all variables x(1), x(2), x(3), and x(4) and the first-order interaction between x(1) and x(3) contributed significantly to the fit, so that they were included in the regression model, yielding the following regression formula: Age = 120.737 - 337.112x(1) - 79.709x(2) - 364.534x(3) - 65.655x(4) + 1531.918x(1)x(3) . The residual standard error of estimated ages was 3.62 years, with 94 degrees of freedom, and the median of the residuals was -0.155 years, with an interquartile range of 4.96 years. The accuracy of the method was ME = 2.8 years, where ME is the mean prediction error. The model also explained 94% of total variance (R(2) = 0.94).     

实验性急性心肌梗死心肌K~+/Na~+、Mg~(2+)/Ca/~(2+)Zn~(2+)/Cu~(2+)比值变化的研究

用结扎家免左冠状动脉建立急性心肌梗死区的模型,探讨梗死区心肌中K~+/Na~+、Mg~(2+)/Ca/~(2+)、Zn~(2+)/Cu~(2+)比值的变化与急性心肌梗死发生时间的规律。结果提示:(1)K~+/Na~+、Mg~(2+)/Ca/~(2+)比值随心肌缺血时间延长呈进行性下降。K~+/Na~+比值在60min、120min实验组与对照组比较有显著性差异(P<0.01);(2)Zn~(2+)/Cu~(2+)比值各实验组与对照组比较无显著性差异(P>0.05),但实验组随缺血时间延长,Zn~(2+)/Cu~(2+)比值呈下降趋势,120min组比15min、30min、60min组降低约1/2(PC<0.01)。测定心肌梗死区K~+/Na~+、Mg~(2+)/Ca/~(2+)比值可以作为显示和判定急性心肌梗死的重要指标。     

A fatality caused by accidental production of hydrogen sulfide.

A 55-year-old male Caucasian truck driver was dead at the scene after breathing hydrogen sulfide (H(2)S) produced by an accidental transfer of sodium hydrogen sulfide (NaHS) from a tanker truck to a tank containing 4% sulfuric acid (H(2)SO(4)) and iron(II) sulfate (FeSO(4)). Autopsy of the decedent's body revealed pulmonary edema and passive congestion in lungs, spleen, kidneys, and adrenal glands. Postmortem biological samples were analyzed for carbon monoxide, cyanide, ethanol, and drugs. Since a potential exposure to H(2)S was involved, blood was also analyzed for sulfide (S(2-)). The analysis entailed isolating S(2-) from blood as H(2)S using 0.5M H(3)PO(4), trapping the gas in 0.1M NaOH, and determining the electromotive force using a sulfide ion specific electrode. Acetaminophen at a concentration of 14.3 microg/ml was found in blood, and metoprolol was detected in the blood, liver, and kidney samples. The blood S(2-) level was determined to be 1.68 microg/ml. It is concluded that the cause of death was H(2)S poisoning associated with a hazardous material accident in an industrial situation.     

Poisoning deaths in Central China (Hubei): A 10-year retrospective study of forensic autopsy cases

A retrospective study of autopsy cases was conducted at the Department of Forensic Medicine, Tongji Medical College (DFM-TMC), in Hubei, China to describe the characteristics of poisoning deaths from 1999 to 2008. A total of 212 poisoning deaths were investigated by DFM-TMC during the 10-year period. The poisoning deaths ranged from 17 cases in 1999 to 27 cases in 2008. Of the 212 cases, 82 deaths (38.7%) were from pesticides, 36 deaths (17.0%) from carbon monoxide, 34 deaths (16.0%) from drugs, 22 deaths (10.4%) from alcohol, 17 deaths (8.0%) from other chemicals, 15 deaths (7.1%) from poisonous plants and animals, and six deaths (2.8%) from heavy metals. Of the 82 pesticide poisoning deaths, 43 (52.4%) cases were caused by rodenticides, mainly tetramine (N = 39). The majority of poisoning deaths were accidents (63.7%), followed by suicides (25.9%) and homicides (3.8%). The manner of death could not be determined in 14 cases (6.6%).     

Simultaneous phenotyping of genetic markers for paternity testing

Time-and cost-saving methods for paternity testing are described. Seventeen genetic systems were divided into six groups: (1) transferrin (Tf), factor B (Bf), and phosphoglucomutase 1 (PGM1); (2) group-specific component (Gc) or alpha 1-antitrypsin (PI) and alpha 2HS-glycoprotein (HSGA); (3) complement components C6 and C7, factor 13B (F13B), and plasminogen (PLG); (4) haptoglobin (Hp), C8 alpha-gamma chain (C81), and factor I (IF); (5) red cell acid phosphatase (ACP), esterase D (ESD), and glutamic-pyruvic transaminase (GPT); and (6) 6-phosphogluconate dehydrogenase (PGD) and glyoxalase I (GLO). Each group of systems was typed simultaneously by electrophoresis or isoelectric focusing (IEF) followed by staining or immunoblotting. These methods are very practical because they afford a considerable saving of time, work and expense, and facilitate semipermanent preservation of electrophoretic patterns.     

听力正常人听性稳态反应阈值与纯音测听阈值的比较

目的 通过比较听性稳态反应（auditory steady-state responses,ASSR）阈值与纯音测听（pure tone audiometry,PTA）阈值,为ASSR技术应用于听力障碍法医学鉴定提供技术数据。建立本实验室ASSR阈值与PTA阈值的校正值。方法 对27例（54耳）正常听力志愿者进行PTA及500、1000、2000和4000Hz的ASSR测试,采用配对t检验法比较测试耳ASSR闽值与PTA阈值的关系;并验证Smart EP-ASSR测试系统校正后的ASSR阈值与PTA阈值的一致性。结果 正常耳ASSR阈值较PTA阈值高（P〈0．05）,各频率差值：500Hz为（22．04±5．79）dB,1000Hz为（11．02±5．44）dB,2000Hz为（12．59±5．89）dB,4000Hz为（17．78±7．25）dB;仪器校正后的ASSR阈值与PTA阈值的差值：500Hz为（-3．96±5．79）dB,1000Hz为（0．02±5．44）dB,2000Hz为（-0．41±5．89）dB,4000Hz为（-1．25±7．25）dB。结论 听力正常人ASSR阈值较盯A阈值高,其差值在各频率不一致．平均为16．9dB。ASSR用于听力障碍法医学鉴定中评估行为听阈时,ASSR阈值需要进行校正。     

The relationship between bedding and face-down death in infancy: mathematical analysis of a respiratory simulation system using an infant mannequin to assess gas diffusibility in bedding

Rebreathing is a model for the relationship between a prone sleeping position and sudden infant death syndrome. This study used a mechanical simulation model to establish the relationship between types of bedding and rebreathing potential for an infant placed prone (face down) at different postnatal ages. The infant mannequin was connected to a respirator set to deliver physiologically appropriate combinations of tidal volume (V(T)) and respiratory rates (RR) across a range of postnatal ages (0-18 months). Before measurements were made, CO(2) flow was regulated to 5+/-0.1% of end-tidal PCO(2) (EtCO(2)). After the model was placed in a prone position, any increase in the fractional concentration of inspired CO(2) (FiCO(2)) was measured. FiCO(2) increased immediately and rapidly, and reached a maximum value within a few minutes. The maximum FiCO(2) ranged from under 2% to over 10%, depending on the bedding. FiCO(2) was also affected by V(T) and RR. This model is not applicable to actual infants because of the large tissue stores of CO(2) in infants; however, it is useful for evaluation of gas diffusibility of bedding and will simplify the investigation of sleeping environments when a baby is found dead with its face covered by soft bedding. In general, the higher the FiCO(2), the greater the rebreathing potential. Theoretically, considering the paucity of body stores of O(2), changes in FiO(2) would be affected not by changes in FiCO(2), but by CO(2) production and gas movement around the infant's face. The rapid decrease of FiO(2) is approximated at the inverse of the FiCO(2) timecourse, suggesting the significance of not only CO(2) accumulation but also O(2) deprivation in the potential space around the baby's face.     

(1S,2S)-1-Methylamino-1-phenyl-2-chloropropane: Route specific marker impurity of methamphetamine synthesized from ephedrine via chloroephedrine

Identification of route specific marker impurities of (S)-(+)-methamphetamine can provide us with very useful information for (S)-(+)-methamphetamine abuse criminal investigation. (1S,2S)-(+)-Chloropseudoephedrine and (1R,2S)-(-)-chloroephedrine are well known impurities of (S)-(+)-methamphetamine synthesized by metal catalyzed hydrogenation of (1R,2S)-(-)-ephedrine or (1S,2S)-(+)-pseudoephedrine. In this report (1S,2S)-1-methylamino-1-phenyl-2-chloropropane is identified as a route specific marker impurity from metal catalyzed hydrogenation method for the synthesis of (1R,2S)-(-)-ephedrine or (1S,2S)-(+)-pseudoephedrine via its chloro-derivative. (1S,2S)-1-Methylamino-1-phenyl-2-chloropropane is a ring-opening compound of cis-1,2-dimethyl-3-phenylaziridine by reacting with HCl in high temperature condition of GC inlet.     

Application of discriminant analysis to differentiate between incorporation of cocaine and its congeners into hair and contamination

The requirement to differentiate between incorporation and external contamination of drugs into hair is undisputed, in particular when dealing with compounds which are administered by sniffing or inhalation (e.g. cocaine). With the aim of making this discrimination, hair samples from cocaine (COC) users (group IN) and seized cocaine samples (group OUT) were compared regarding the parameters benzoylecgonine (BZE), ecgonine methyl ester (EME), ecgonine (ECG), anhydroecgonine methyl ester (AEME), cocaethylene (CE) and norcocaine (NCOC). Since most of these compounds may be minor by-products of COC or be formed by biotransformation or chemical degradation, the stability of each substance was carefully examined. COC was found to be converted into significant amounts of BZE, EME and ECG even under mild extraction conditions, while traces of NCOC proved to be a ubiquitous by-product of COC. Cocaine positive hairs and seized cocaine samples (diluted to relevant concentrations) were equally preprocessed and analyzed by LC-MS-MS. Out of the metabolites listed above, NCOC, CE and AEME (each normalised to COC) were significantly increased in the incorporation group (i.e. hair samples from cocaine users). Based on this approach, a statistical discriminant analysis enabled us to make a prediction (and estimation of uncertainty) for each cocaine positive hair sample as to its likelihood of belonging to the group of cocaine users or of being contaminated.     

The association between body mass index and pulmonary thromboembolism in an autopsy population

Abstract: To evaluate the association between obesity and pulmonary thromboembolism (PTE) in a forensic context, 160 autopsy cases of fatal PTE were compared with age‐ and gender‐matched controls. The mean age of cases was 66 years (range 26–98 years; M/F 74:86). The mean body mass index (BMI) of cases with PTE was 30.88 (range 14.95–79.51), which was significantly higher than in the controls (mean BMI = 25.33; range 12.49–61.84) (p < 0.0001). Comparing the group with PTE with controls showed that five (3.1%) compared to 20 (12.5%) were underweight, 39 (24.4%) compared to 67 (41.88%) were of normal weight, 49 (30.63%) compared to 43 (26.88%) were overweight, 43 (26.88%) compared to 24 (15%) were obese, and 24 (15.0%) compared to six (3.75%) were morbidly obese. In each category of above‐normal BMIs, there were significantly greater numbers in the groups with PTE: overweight (p < 0.01), obese (p < 0.001), and morbidly obese (p < 0.0001).     

A case of death after ingestion of an agrochemical spreading agent

An agrochemical spreading agent was found near the slightly decomposed corpse of a deceased female. The appearance of the stomach contents suggested that ingestion of a surfactant had occurred before death. The spreading agent was found to contain nonionic nonylphenol ethoxylates (NPEO(n)) and anionic sulfonated naphthalene-formaldehyde condensates (SNFC(n)). A solid phase extraction cartridge containing a mixed reversed phase-weak anion exchange sorbent (Oasis WAX, Waters) was used to successfully extract both NPEO(n) and SNFC(n) from the blood. The cartridge was preconditioned with methanol and acetic acid (AcOH). After the dilute blood sample was applied to the cartridge, it was washed with AcOH, and then NPEO(n) and SNFC(n) were eluted with methanol/dichloromethane (7:3, v/v) and 5% NH(3)/80% methanol, respectively. The concentrations of NPEO(n=2-9) and SNFC(n=0) in the blood sample were 7.7μg/mL and 1.8mg/mL, respectively. It is possible that postmortem changes increased the concentration of SNFC(n=0) monomer by breaking down the polymer. However, the behavior of these compounds in the human body is unclear and further case studies are needed to investigate this result.     

Hair analysis for delta(9)-THC,delta(9)-THC-COOH,CBN and CBD,by GC/MS-EI. Comparison with GC/MS-NCI for delta(9)-THC-COOH

A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit.