A preliminary investigation into the comparison of dissolution/digestion techniques for the chemical characterization of polyurethane foam

Due to their widespread use in domestic and commercial premises, polyurethane foams, as either fragmented or bulk foam, are types of evidence commonly found at crime scenes. The traditional approach to determining the evidential value of polyurethane foam (PF) involves comparing recovered and control fragments under low and high magnification, under various lighting conditions, as well as the comparison of their respective dye spectra. As with most forms of trace evidence, chemical comparison is also desirable. In this work, two approaches to chemically comparing foam fragments were investigated, i.e. inductively coupled plasma–optical emission spectrometry (ICP–OES) analysis of the Tin (Sn) content in different foam types; and gas chromatography–flame ionization detection (GC–FID) analysis of soluble components in PFs mobilized by dichloromethane. Seven different foam types were studied and their Sn content was found to be different. They also produced characteristic GC–FID chromatographic profiles whose compounds were identified with gas chromatography–mass spectrometry (GC–MS) analysis. This study suggests that incorporating chemical data obtained from GC–FID/GC–MS and ICP–OES into a case involving PF could be advantageous, as this will enable the forensic scientist to broaden the comparison between control and recovered fragments, and further assess the strength of the evidence. However, ICP–OES analysis is a destructive technique with a relatively short sample turnaround time, whilst GC–FID analysis is more time-consuming and non-destructive, requiring corroboration with GC–MS data. The values of these two analytical techniques in the forensic chemical characterization of PFs are discussed.     

Drugs WorkBook (DWB): A tool for the analysis of illicit drugs in seized materials

Accurate and reliable analytical measurements are essential when data are to be used to assist the Court in deciding whether or not a drug offence has been committed and therefore about either the innocence or guilt of the accused. The Italian law on drugs demands that compliance with specification limits be assessed on the basis of the actual content of controlled substance contained in seized materials. As a consequence, the role of measurement uncertainty, significant figures and rounding errors becomes critical. In order to assist analysts of forensic toxicology laboratories with illicit drug-related cases, a software tool named Drugs WorkBook (DWB) has been developed. The tool is useful for the quantification of illicit drugs in seized materials along with their measurement uncertainties, the assessment of compliance to specification limits, the printing of comprehensive laboratory reports and the organization of case archives. Other quality control topics, such as control charts, are included. The tool's databases can be edited by the user and maintained up to date. The tool is made freely available to the scientific community.     

Review of analytical techniques for arson residues

Arson is a serious crime that affects society through cost, property damage, and loss of life. It is important that the methods and technologies applied by fire investigators in detection of evidence and subsequent analyses have a high degree of reliability, sensitivity, and be subject to rigorous quality control and assurance. There have been considerable advances in the field of arson investigation since the 1950s. Classification of ignitable liquids has been updated to include many new categories due to developments in the petroleum industry. Techniques such as steam or vacuum distillation and gas chromatography (GC) with flame ionization detection that may have been considered acceptable--even a benchmark--40 years ago, are nowadays generally disfavored, to the extent that their implementation may almost be considered as ignorance in the field. The advent of readily available mass spectrometric techniques has revolutionized the field of fire debris analysis, increasing the degree of sensitivity and discrimination possible considerably. Multi-dimensional GC--particularly GC x GC--while not yet widely applied, is rapidly gaining recognition as an important technique. This comprehensive review focuses on techniques and practices used in fire investigation, from scene investigation to analysis.     

X-ray powder diffraction data for some drugs, excipients, and adulterants in illicit samples.

X-ray powder diffraction data have been developed or refined for the identification of drugs, excipients, and adulterants found in illicit preparations.     

Tracing the source of illicit drugs through plastic packaging--a database

Common plastic drug packaging material available in Australia and in Asia was analyzed using a standard protocol including optical examination, UV-visible and Fourier transform infrared spectrometry. The aims were to determine whether there are significant differences between different sources, to establish the evidential value of these examinations, and to build a database of common packaging material. Visual examination was the most effective means for discriminating samples. Thickness and weight measurements provided useful information. Visualization of machining marks using crossed polarized light was found to be useful in the comparison process. UV-visible spectrophotometry has some value for distinguishing samples. Fourier transform infrared analysis was a good technique for determination of the polymer composition of the packaging. Significant differences were observed between Australian and overseas samples. The "Australian Database of Drug Packaging Materials" was created to systematically collate all of the collected data for application on personal computers. It is concluded that the properties of plastic packaging materials can be excellent indicators for identifying the specfic brand or origin of the packaging.     

Evaluation of the IDS One-Step ELISA kits for the detection of illicit drugs in hair

This work presents the validation of a new immunological assay, the One-Step enzyme-linked immunosorbent assay (ELISA) tests from International Diagnostic Systems Corp. for the screening of drugs of abuse (cannabis, amphetamines, opiates, and cocaine) in human hair, with subsequent GC-MS confirmation. After decontamination and segmentation into small pieces, 50 mg of hair sample were incubated in 1 ml of methanol during 16 h at 40 degrees C. A 100 microL aliquot was collected and evaporated to dryness in presence of 100 microL of methanol/hydrochloric acid (99:1, v/v) to avoid amphetamines loss. The dried extract was dissolved in 100 microL of the "sample and standard diluent" solution included in the kit. This solution was submitted to analysis according to the recommended instructions of the manufacturer. During the validation phase, GC-MS confirmations were conducted according to our fully validated and published methods for opiates, cocaine, cannabis, and amphetamines determinations in hair. In a last development step, these procedures were slightly modified to directly confirm ELISA results by GC-MS using the methanolic extract. Ninety-three specimens were simultaneously screened by the ELISA tests (103 for tetrahydrocannabinol (THC)) and confirmed by GC-MS. Twenty were found positive for cannabis (THC: 0.10-6.50 ng/mg), 21 for cocaine (0.50-55.20 ng/mg), 24 for opiates (6-acetylmorphine (6-AM): 0.20-11.60 ng/mg, MOR: 0.20-8.90 ng/mg, codeine (COD): 0.20-5.90 ng/mg), and 13 for amphetamines (AP: 0.20 and 0.27 ng/mg, methamphetamine (MAP): 0.30 and 1.10 ng/mg, methylenedioxymethamphetamine (MDMA): 0.22-17.80 ng/mg). No false negative results were observed according to the Society of Hair Testing's (SoHT) cutoffs (0.5 ng/mg for cocaine, 0.2 ng/mg for opiates and amphetamines, and 0.1 ng/mg for THC). The One-Step ELISA kits appear suitable due to their sensitivity and specificity for drug of abuse screening in hair. This technology should find interest in workplace drug testing or driving license regranting, especially when many samples have to be tested with a high rate of negative samples, as ELISA is an easy and high-throughput method.     

Bayesian adaptive approach to estimating sample sizes for seizures of illicit drugs

A considerable amount of discussion can be found in the forensics literature about the issue of using statistical sampling to obtain for chemical analyses an appropriate subset of units from a police seizure suspected to contain illicit material. Use of the Bayesian paradigm has been suggested as the most suitable statistical approach to solving the question of how large a sample needs to be to ensure legally and practically acceptable purposes. Here, we introduce a hypergeometric sampling model combined with a specific prior distribution for the homogeneity of the seizure, where a parameter for the analyst's expectation of homogeneity (α) is included. Our results show how an adaptive approach to sampling can minimize the practical efforts needed in the laboratory analyses, as the model allows the scientist to decide sequentially how to proceed, while maintaining a sufficiently high confidence in the conclusions.     

Review: Pharmacokinetics of illicit drugs in oral fluid

This article reviews studies that have measured drug concentrations in oral fluid following controlled dosing regimens. A total of 23 studies have been identified over the last 15 years. These show that the amphetamines including designer amphetamines, cocaine, cannabis and cocaine are quickly found in oral fluid following dosing and usually have similar time-courses to that in plasma. Following common doses peak oral fluid concentrations exceed 0.1 microg/mL and often even 1 microg/mL. The drug concentration will depend on whether a dilution step occurs with buffer as part of the sampling procedure. The uses of collectors that stimulate oral fluid usually reduce the drug concentration compared to a non-stimulated manner. This reduction will not disadvantage the recipient since it will potentially reduce the detectability of drug in oral fluid compared to non-stimulated collections. Only one recent study has been reported for a benzodiazepine. This showed nanogram per milliliter concentrations for flunitrazepam. More studies are required for benzodiazepines and indeed for other drugs, particularly in multiple drug situations and where disease may affect the pharmacokinetics of drugs.     

A rapid gas chromatographic method for the fingerprinting of illicit cocaine samples.

A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.     

Review: Pharmacokinetics of illicit drugs in oral fluid

This article reviews studies that have measured drug concentrations in oral fluid following controlled dosing regimens. A total of 23 studies have been identified over the last 15 years. These show that the amphetamines including designer amphetamines, cocaine, cannabis and cocaine are quickly found in oral fluid following dosing and usually have similar time-courses to that in plasma. Following common doses peak oral fluid concentrations exceed 0.1 μg/mL and often even 1 μg/mL. The drug concentration will depend on whether a dilution step occurs with buffer as part of the sampling procedure. The uses of collectors that stimulate oral fluid usually reduce the drug concentration compared to a non-stimulated manner. This reduction will not disadvantage the recipient since it will potentially reduce the detectablity of drug in oral fluid compared to non-stimulated collections. Only one recent study has been reported for a benzodiazepine. This showed nanogram per milliliter concentrations for flunitrazepam. More studies are required for benzodiazepines and indeed for other drugs, particularly in multiple drug situations and where disease may affect the pharmacokinetics of drugs.     

Violent crime and substance abuse: a medico-legal comparison between deceased users of anabolic androgenic steroids and abusers of illicit drugs

Several case reports and survey studies have indicated that abuse of anabolic androgenic steroids (AAS) often leads to increased aggressiveness and feelings of hostility that may occasionally trigger violent behaviour. Other observations indicate that many users of AAS also abuse alcohol and/or various illegal substances. Since substance abuse is a well-known risk factor for violent behaviour, it could be that violence committed by AAS users might, at least in many cases, actually be caused by abuse of other drugs. In order to examine this possibility further here, the criminal histories (in terms of incidences of convictions) of deceased users of AAS with (AASpos-subst.pos) and without (AASpos-subst.neg) signs of abuse of other illegal substances were compared to the corresponding histories of deceased users of illicit substances testing negatively for AAS (subst.pos-AASneg) at the time of autopsy. The risk of being convicted for a crime against property was significantly higher in the subst.pos-AASneg group than in either the AASpos-subst.neg or AASpos-subst.pos groups (RR=0.048 versus 0.408). At the same time, the risk of being convicted for a crime of violence was at least as high for the two AAS-positive groups as for the AAS-negative group. Furthermore, when compared with the first 3 years after the first criminal conviction, a pronounced increase in the proportion of incidence of violent crimes and a marked reduction in the proportion of incidence of crime against property was observed during the 3-year period immediately preceding death only among the AASpos-subst.neg subjects. In conclusion, the incidence of violent crime among users of AAS without signs of other drug abuse was comparable to the corresponding incidences for drug addicts without AAS use. This observation suggests that the violent criminality observed among AAS users is not confounded in any systematic fashion by abuse of other drugs. The findings also indicate that use of AAS in certain predisposed individuals might cause a high rate of violent crimes, especially if the use of AAS is combined with the use of other illegal substances.     

A survey of extraction techniques for drugs of abuse in urine

Sixty nine participants in the United Kingdom national external quality assessment scheme for drugs of abuse in urine reported details of their sample extraction technique by questionnaire. Laboratories were categorised by differences in technique and their analytical test results compared for samples containing D-amfetamine 0.4 (4) and 0.8 (3) mg/l, morphine 0.4 (4) and 0.8 (4)mg/l, and benzoylecgonine 0.15/0.2 (2) and 0.45/0.5 (4) mg/l. Values in parentheses are numbers of samples. For amfetamine, there was no significant difference in the frequency of true positive results between liquid-liquid or solid phase extraction and the Toxi-Lab A system at 0.8 mg/l. Toxi-Lab A gave significantly fewer positives when operating below its specified threshold at 0.4 mg/l. Paradoxically, laboratories using >5 ml urine volume performed less well. Acidification of the extract before volume reduction gave significantly more true positives. For extraction of morphine, solid phase systems significantly outperformed both liquid-liquid and the Toxi-Lab A system at both 0.8 and 0.4 mg/l. No significant differences between extraction techniques were demonstrated for analysis of benzoylecgonine.     

A review of recent advances in impurity profiling of illicit MDMA samples

Profiling illicit ecstasy tablets has the potential to become an invaluable tool in the crackdown on drug trafficking, but that potential has yet to be fully realized. The impurity profile of an ecstasy tablet can be used to determine the method employed to synthesize the actual controlled substance, which in most cases, is 3,4-methylenedioxymethamphetamine (MDMA). Tablets can then be linked to a common synthetic route, potentially to a common manufacturer, and possibly even to a common manufacturing batch, based on the impurities present. Current methods for profiling MDMA tablets typically involve extracting the organic impurities for analysis by gas chromatography-mass spectrometry. The potential of profiling the trace metals present in tablets has begun to be investigated while more robust statistical and chemometric procedures are being applied to compare and link tablets. This article reviews the recent advances in MDMA impurity profiling from 2002 up to the end of 2006.     

A methodology for illicit heroin seizures comparison in a drug intelligence perspective using large databases

To characterise links between different illicit drugs chemical profiles, various distance or correlation measurements are available.Different comparison methods have been tested and a method based on a correlation coefficient using a square cosine function was chosen to compare heroin chemical profiles. Its functioning and graphical representation are described. An assessment of the number of false positives is calculated and lead to a negligible number.Moreover, it emerges from the studies that possible variations in impurity peak areas subject to possible degradations do not influence the C correlation value nor question the already established links.This solid, reliable and simple method appears therefore suitable for heroin samples comparison, links profiling and routine use.     

The dynamics of illicit drugs production: Future sources and threats

This paper examines the opportunities for illicit drugs production which arise out of the economic, political and social conditions of some countries. These drivers can help us to understand the geographical pattern of global drugs sources and assist in the process of identifying those parts of the world in which new production opportunities are arising. It was found that there is not a homogenous set of risks which contributes to drugs production. Instead, the particular contexts which are conductive to drug production activities varies for different drug types. This has influenced the different patterns of drugs production for highly refined, organic drugs, such as cocaine and heroin, compared to synthetic drugs. The nature of developments which could trigger new areas of drug production are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

The recovery of illicit drugs from oral fluid sampling devices

Testing for drugs in oral fluid is a convenient procedure for determining recent drug use. A number of issues are still to be resolved and this paper investigates the effects of storage systems on drug stability and recovery using three different collection devices supplied by Cozart, Immunalysis and Microgenics (third party). Drugs were analysed using a range of immunoassay systems followed by MS confirmation and quantitation. The reproducibility of the weight of specimen collected was excellent (CV<10%) for the three collection devices tested. Of the three systems studied, only the Cozart product gave acceptable recovery of THC from drug-spiked oral fluid. A combination of Cozart, Immunalysis and Diagnostix immunoassays with the Cozart collection system gave the most sensitive and discriminating screening assays for the drugs studied, namely THC, benzodiazepines, methamphetamine and morphine. Storage at either 5 degrees C or room temperature had no significant effect on drug recoveries.     

Capillary electrophoresis: a new tool in forensic toxicology. Applications and prospects in hair analysis for illicit drugs

Capillary electrophoresis, the modern approach to instrumental electrophoresis, is probably the most rapidly expanding analytical technique that has appeared in recent years. In the hands of forensic toxicologists, capillary electrophoresis (CE) represents a powerful new analytical tool, which has proved suitable for the investigation of illicit drugs in seized preparations and also in complex biological matrices, among which is hair. CE can be applied according to different separation mechanisms, and among those that are toxicologically relevant are capillary zone electrophoresis and micellar electrokinetic capillary chromatography, which display different selectivities. For the investigation of hair for drugs of abuse, capillary electrophoresis proved effective, providing simultaneous determinations of different drugs without derivatization, with acceptable sensitivity (typically better than 1 ng of drug per mg of hair). The possibility of carrying out determinations of the same analytes, based on different separation mechanisms (capillary zone electrophoresis and micellar electrokinetic chromatography) with the same instrumentation, simply changing the buffer composition, provides an interesting possibility of ‘internal’ confirmation of the results.     

Evaluation of the IDS One-Step™ ELISA kits for the detection of illicit drugs in hair

This work presents the validation of a new immunological assay, the One-Step™ enzyme-linked immunosorbent assay (ELISA) tests from International Diagnostic Systems Corp. for the screening of drugs of abuse (cannabis, amphetamines, opiates, and cocaine) in human hair, with subsequent GC–MS confirmation. After decontamination and segmentation into small pieces, 50 mg of hair sample were incubated in 1 ml of methanol during 16 h at 40 °C. A 100 μL aliquot was collected and evaporated to dryness in presence of 100 μL of methanol/hydrochloric acid (99:1, v/v) to avoid amphetamines loss. The dried extract was dissolved in 100 μL of the “sample and standard diluent” solution included in the kit. This solution was submitted to analysis according to the recommended instructions of the manufacturer. During the validation phase, GC–MS confirmations were conducted according to our fully validated and published methods for opiates, cocaine, cannabis, and amphetamines determinations in hair. In a last development step, these procedures were slightly modified to directly confirm ELISA results by GC–MS using the methanolic extract. Ninety-three specimens were simultaneously screened by the ELISA tests (103 for tetrahydrocannabinol (THC)) and confirmed by GC–MS. Twenty were found positive for cannabis (THC: 0.10–6.50 ng/mg), 21 for cocaine (0.50–55.20 ng/mg), 24 for opiates (6-acetylmorphine (6-AM): 0.20–11.60 ng/mg, MOR: 0.20–8.90 ng/mg, codeine (COD): 0.20–5.90 ng/mg), and 13 for amphetamines (AP: 0.20 and 0.27 ng/mg, methamphetamine (MAP): 0.30 and 1.10 ng/mg, methylenedioxymethamphetamine (MDMA): 0.22–17.80 ng/mg). No false negative results were observed according to the Society of Hair Testing's (SoHT) cutoffs (0.5 ng/mg for cocaine, 0.2 ng/mg for opiates and amphetamines, and 0.1 ng/mg for THC). The One-Step™ ELISA kits appear suitable due to their sensitivity and specificity for drug of abuse screening in hair. This technology should find interest in workplace drug testing or driving license regranting, especially when many samples have to be tested with a high rate of negative samples, as ELISA is an easy and high-throughput method.     

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.     

Alcohol,illicit drugs and medicinal drugs in fatally injured drivers in Spain between 1991 and 2000

The aim of this study was to assess the presence of alcohol, illicit drugs and medicinal drugs among Spanish drivers involved in fatal road accidents between 1991 and 2000. Samples were obtained for 5745 drivers killed in road accidents from January 1991 to December 2000. Of the samples, 91.7% represented males and 8.3% females; 40.7% were under 30 years of age, 31.9% were under 31-50 years of age, 19.5% were over 51 years of age, and for 7.9% the age was unknown. Between 1991 and 2000, some type of psychoactive substance was detected among 50.1% of those drivers killed in road accidents, this being mainly alcohol (43.8%) and, less frequently, illicit drugs (8.8%) and medicinal drugs (4.7%). In all the cases, in which alcohol was detected, combined use with other substances accounted for only 12.5%, whilst in the case of illicit and medicinal drugs, figures representing combined use with other substances were 75.6% for the former and 65.8% for the latter. For one in every three cases (32.0%), a blood alcohol level over 0.8 g/l was recorded; cocaine (5.2%), opiates (3.2%) and cannabis (2.2%) were the three illicit drugs most frequently detected. Among medicinal drugs, were benzodiazepines (3.4%), anti-depressant drugs (0.6%) and analgesics (0.4%). The results show the frequent presence of psychoactive substances, particularly alcohol, among Spanish motor vehicle users involved in fatal road accidents. It should be pointed out that illicit and medicinal drugs in combination with other substances were a common feature.