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Background: Biochemical toxicology in suicides provides a template to improve preventive interventions in cases of suicide. The menu for biochemical toxicological analysis in coroners' cases is not prescriptive in Ireland or in the United Kingdom. The aim of the study was to confirm that reliance on the results of an immunoassay screen for drugs of abuse and common analgesics in order to select samples for compound confirmation by gas chromatography-mass spectrometry is likely to understate the potential role of drugs in suicide. Blood and urine samples were analyzed using enzyme immunoassay, alcohols by gas chromatography and urines were screened by Bio-Rad's Rapid Emergency Drug Identification (REMEDi) system. Laboratory data from analysis of 132 cases of suicide, including 101 cases of hanging revealed that 83 % were male confirming suicide as a male epidemic. Overall, alcohol was a factor in 57 %, benzodiazepines in 26 %, cannabinoids in 11 %, opioids in 19.7 %, sympathomimetics in 7.5 %, cocaine in 4.5 %, antidepressants 22 %, antipsychotics in 10 %, hypnotics in 5 %, and antihistamines in 4 % of these cases. Screening compounds in cases of hanging and other suicides should extend beyond the narrow focus of alcohol and illicit drugs to include a wide spectrum of psychoactive and other compounds as a standard procedure. The wide range of licit and illicit compounds found in these cases reflects current experience and dictates the necessity for chromatographic screening with mass spectroscopy confirmation in all cases as best practice.

The blood alcohol concentration (BAC) is an important evidence to determine the alcohol level at the time of death. But due to the postmortem synthesis and diffusion of alcohol, the cadaveric BAC can not always represent the original BAC at the time of death. It is a crucial problem to determine the original level in corpse. The article reviewed the following points: the distribution in corpse, and how to sample, the influences on the diffusion of alcohol and putrefaction, the discussion about alcohol mass concentration measure methods.

This article concerns the use of urine as a biological specimen for determination of alcohol in clinical and forensic toxicology and discusses factors that might influence variability in the urine/blood concentration ratio of alcohol. A large number of human drinking experiments were conducted to determine the time course of urine-alcohol concentrations (UAC) in relation to blood-alcohol concentrations (BAC). The UAC and BAC curves were shifted in time and the BAC curve always began to decrease before the UAC started to decline. During the early absorption phase the UAC/BAC ratio was less than unity, whereas in the late absorption/distribution period the ratio was between 1.0-1.2. On reaching the post-absorptive phase, the UAC always exceeded BAC and UAC/BAC ratios averaged 1.3-1.4, increasing appreciably as BAC decreased towards zero. Alcohol-induced diuresis was most pronounced during the rising portion of the BAC curve and near to the peak value. After about 2 hours post-drinking, the production rate of urine diminished to the pre-drinking rate of about 0.5-1 mL/min. Drinking water during the post-absorptive phase of the alcohol curve produced dilute urine, as reflected in lower creatinine content and osmolality, although the concentration of ethanol remained unchanged. After subjects drank a moderate dose of ethanol (0.54-0.85 g/kg) about 2% of the dose was recoverable in the urine after 7 hours. Ethyl glucuronide, a minor metabolite of ethanol, was measured in urine samples from drunk drivers. The UAC/BAC ratio of ethanol in drunk drivers did not depend on the creatinine content of the urine and therefore the relative dilution of the specimens. When alcohol-free urine was spiked with glucose and infected with the yeast species Candida albicans, ethanol was produced by fermentation after approximately 24 hours storage at room temperature. This post-sampling synthesis of ethanol was prevented by sodium fluoride (1% weight by volume) in the urine tubes or by keeping the specimens in the cold (4 degrees C). The UAC and BAC were highly correlated (r > 0.95) in drunk drivers and in autopsy cases, although the residual standard deviations were appreciable. This speaks against attempting to estimate BAC indirectly from UAC in any individual case. The UAC/BAC ratio and the change in UAC between two successive voids can help to resolve whether a large amount of alcohol had recently been consumed. This information is useful to support or challenge allegations of drinking alcohol after driving, which has become known as the hip-flask defence.

Many suspected victims of surreptitious drug and/or alcohol administration may present to hospitals or healthcare centres and never come to the attention of forensic or law enforcement professionals. Therefore, it is necessary to include clinical toxicological findings in order to assess the growing perception that instances have become more widespread within society. Between July 2002 and June 2004, 180 requests were received for toxicological analysis of individuals presenting to their GP or hospital following self-reported or suspected surreptitious drug administration (e.g. "spiked drink"). There was a rise of 77% in the number of requests from 2002-2003 to 2003-2004 which peaked in December of each year (most likely due to the increased socialization of people during the festive season). Between 2002 and 2004, 34% of patients were male and 66% were female with an overall average age of 25 (range 11-73). Following urinary analysis using immunoassay and gas chromatography (mass spectrometry, flame-ionisation detection and nitrogen-phosphorus detection), 59% of cases were negative for drugs and alcohol in 2002-2003 and 51% in 2003-2004. Drugs or alcohol were detected in 32% of cases in 2002-2003 and in 45% in 2003-2004. Out of the 169 cases analysed, ethanol (alcohol) was the most commonly detected compound (24% of cases), followed by amphetamines (amphetamine, MDMA, MDA, MDEA--11% of cases), cannabinoids (9% of cases), benzodiazepines (temazepam, nordiazepam, oxazepam--9% of cases), cocaine (4% of cases), opiates (dihydrocodeine, codeine--2% of cases), chlorpheniramine (0.6% of cases), ephedrine 0.6% of cases), fluoxetine (0.6% of cases), tramadol (0.6% of cases) and zopiclone (0.6% of cases). No gamma-hydroxybutyrate (GHB), gamma-butyrolactone (GBL) or flunitrazepam was detected in the cases analysed.

This study was prompted by a recent judgment in the Royal Courts of Justice (Gregory v. Director of Public Prosecutions, 2002) in a case of driving a motor vehicle after consuming too much alcohol (Road Traffic Act 1988). An expert witness for the defence alleged that a deficient volume of blood in the tube sent for analysis meant an excess amount of sodium fluoride (NaF) preservative, which would increase the concentration of ethanol, determined by headspace gas chromatography (HS-GC), owing to a salting-out effect. The prosecution did not produce expert evidence to rebut this argument and the drunk driving suspect was acquitted. A small volume of blood and excess sodium fluoride might have increased the concentration of ethanol in the air-space in the tube sent for analysis but this does not mean that the result of the HS-GC analysis would be higher. This follows because prior to analysis an aliquot of blood is removed and diluted (approximately 10 times) with n-propanol as the internal standard. The dilution lowers the concentration of NaF in the blood and for quantitative analysis the ratio of the ethanol to n-propanol response is measured. The use of a ratio also helps to compensate for any salting-out effect of ethanol. Our experiments showed that a deficient volume of blood and excess NaF actually lowered the concentration of ethanol by 2-3% compared with heparinised blood. Seemingly, n-propanol (n-PrOH) a 3-carbon straight chain alcohol is salted out slightly more effectively than the 2-carbon ethanol (EtOH) causing a lower peak area ratio (EtOH/n-PrOH) and a lower apparent concentration of ethanol. In a separate study, we showed that the concentration of ethanol was lowered even more when a 4-carbon alcohol (t-butanol) was used as the internal standard.

The concentration of ethanol in blood and urine provides important evidence in criminal and civil litigation when alcohol-related crimes are investigated (e.g., drunk driving). The determination of ethanol in body fluids is a routine procedure at forensic chemistry and toxicology laboratories and when gas chromatographic methods are used accurate and precise results are obtained. However, the risk for artifactual formation of ethanol, especially in postmortem specimens, always needs to be considered. The ratio of 5-HTOL/5-HIAA in urine provides a useful way to distinguish between ethanol produced after death, or generated in vitro after sampling, from the ethanol consumed. This article describes the application of the 5-HTOL/5-HIAA ratio as a biochemical marker for acute alcohol intake in various forensic situations. Examples include suspected drunk drivers, rape victims, and medico-legal autopsies where forensic ethanol analysis is requested.

The relationship between ethanol and risk of heroin overdosage was studied. Statistical processing of the results of forensic chemical analysis (460 expert evaluations) carried out in Chelyabinsk Regional Bureau of Forensic Medical Expert Evaluations in 2000 was carried out. The results of morphine and ethanol measurements in the blood and urine from corpses where deaths ensued from narcotic or ethanol poisoning, were analyzed. The concentrations of morphine in the blood and urine were measured on a gaseous chromatographer with mass-selective detector (Hewlett Packard HP 6890/HP-5972). Methods for measuring urinary and blood morphine are described. The results of statistical analysis demonstrated relationships between the age and ethanol concentrations in the blood and urine; blood ethanol and total urinary and blood morphine concentrations; blood concentration of free morphine and presence of 6-monoacetylmorphine in the blood. The authors conclude that the presence of ethanol in the blood together with morphine drastically augments the risk of rapid death from respiration arrest. It can also lead to a relatively high risk of overdosage in experienced narcomaniacs using heroin and ethanol.

A simple, sensitive, and reliable method was developed for the confirmation of nonroutine volatiles in the investigation of two traffic fatalities. Solid-phase microextraction (SPME) fibers were used to extract volatile compounds from the headspace of sample vials; components were subsequently analyzed by gas chromatography-mass spectrometry (GC-MS). In the first case, ethanol and methylene chloride were detected in a urine sample by headspace SPME and GC-MS. The second case involved the analysis of volatile petroleum products from submitted specimens by headspace SPME and GC-MS. In both cases, SPME and GC-MS analyses provided crucial evidence in the investigation of the traffic fatalities.

Solutions are reported here for two problems in automated headspace gas chromatographic analysis for ethanol. The first is the catalytic oxidation of ethanol by oxyhemoglobin, a process that is limited only by the amount of oxygen in the sealed vessel. This reaction is prevented by the addition of sodium dithionite. The other problem, the lack of a suitable salting-out agent, led to the selection of ammonium sulfate, which improved recovery of ethanol as well as enhancing method precision. A procedure incorporating these improvements is described.