Guido Romano

Determination of drugs of abuse in hair: evaluation of external heroin contamination and risk of false positives

One of the most controversial point regarding the validity of hair testing is the risk of false positive due to external contamination. The aim of our experience is to verify if a 5 consecutive days contamination with a small amount of a powdered mixture of heroin hydrochloride and acetylcodeine hydrochloride (10:1 w/w) will last sufficiently long to make a contaminated subject indistinguishable from active users, and if normal washing practices together with the decontamination procedure are sufficient to completely remove the external contamination. Our results suggest that decontamination procedures are not sufficient to remove drugs penetrated into hair from external source. In fact, all contaminated subjects were positive for opiates (heroin, 6-MAM, morphine, acetylcodeine and codeine) for at least 3 months. Significant 6-MAM concentrations (>0.5 ng/mg) were found in each subject until 6th week. Further, 6-MAM/morphine ratio were always above 1.3.

Application of principal components analysis to the evaluation and selection of eluent systems for the thin-layer chromatography of basic and neutral drugs

Abstract The R F values of 55 drugs in 40 eluent mixtures are reported. Principal component analysis of these data provides a four-significant-components model, which explains 92% of the total variance. This analysis, showing that the eluent mixtures cluster into different groups according to their information content, provides a reliable criterion for the choice of optimal eluents. Four eluent mixtures of [ethyl acetate—methanol—30% ammonia (85:10:5), cyclohexane—toluene—diethylamine (65:25:10), ethyl acetate—chloroform (50:50) and acetone with the plate dipped in potassium hydroxide solution), chosen on the basis of the above criterion and of the R F reproducibility, provide a two significant principal components model that can be used for the identification of unknown samples.

The pathogenetic role of adulterants in 5 cases of drug addicts with a fatal outcome

The purpose of the present study is to determine the role of lidocaine, caffeine and dextromethorphan, used as adulterant substances, in five cases of drug overdose which have come to our attention. Taking into account the pharmacological mechanism, blood concentration and route of administration (intravenous) we evaluated the hypothesis that these substances could act with a synergistic effect - or at least additive - with the illicit drugs on the central nervous system and cardiovascular system.

Post mortem concentrations of endogenous gamma hydroxybutyric acid (GHB) and in vitro formation in stored blood and urine samples

Gamma-hydroxybutyrate (GHB) is a central nervous system depressant, primarily used as a recreational drug of abuse with numerous names. It has also been involved in various instances of drug-facilitated sexual assault due to its potential incapacitating effects. The first aim of this paper is to measure the post-mortem concentration of endogenous GHB in whole blood and urine samples of 30 GHB free-users, who have been divided according to the post-mortem interval (PMI) in three groups (first group: 24-36h; second group: 37-72h; third group: 73-192h), trying to evaluate the role of PMI in affecting post mortem levels. Second, the Authors have evaluated the new formation of GHB in vitro in blood and urine samples of the three groups, which have been stored at -20°C, 4°C and 20°C over a period of one month. The concentrations were measured by GC-MS after liquid-liquid extraction according to the method validated and published by Elliot (For. Sci. Int., 2003). For urine samples, GHB concentrations were creatinine-normalized. In the first group the GHB mean concentration measured after autopsy was: 2.14mg/L (range 0.54-3.21mg/L) in blood and 3.90mg/g (range 0.60-4.81mg/g) in urine; in the second group it was: 5.13mg/L (range 1.11-9.60mg/L) in blood and 3.93mg/g (range 0.91-7.25mg/g) in urine; in the third group it was: 11.8mg/L (range 3.95-24.12mg/L) in blood and 9.83mg/g (range 3.67-21.90mg/g) in urine. The results obtained in blood and urine samples showed a statistically significant difference among groups (p<0.001) in the first analysis performed immediately after autopsy. Throughout the period of investigation up to 4 weeks, the comparison of storage temperatures within each group showed in blood and urine samples a mean difference at 20°C compared to -20°C not statistically significant at the 10% level. These findings allow us to affirm that the PMI strongly affects the post mortem production of GHB in blood and urine samples. Regarding the new formation of GHB in vitro both in blood and urine samples of the three groups, which have been stored at -20°C, 4°C and 20°C over a period of one month, although there was no significant increases of GHB levels throughout the period of investigation, the lowest increases were found both in blood and urine at -20°C, therefore we recommend the latter as optimal storage temperature.

A fatal case of benzene poisoning

Chronic effects following repeated exposure to low doses of benzene have been well assessed, whereas few data are available about acute exposure to benzene. We report a case of fatal acute intoxication which occurred aboard a chemical cargo ship. Autopsy findings included blood clots inside the heart and main vessels, multi-organ congestion, pulmonary edema and the presence of many vibices in the hypostatic areas. Toxicological analysis of blood and urine showed a benzene concentration of 31.67 and 2.26 micrograms/mL, respectively; high concentrations of benzene (microgram/g) were also found in the lungs (22.23), liver (378.60), brain (178.66), heart (182.57) and kidneys (75.15). The above data provide evidence for benzene distribution in various organs.

A suicidal poisoning due to tramadol. A metabolic approach to death investigation

Tramadol is a synthetic opioid, widely used for post-surgical and chronic pain. Lethal overdose due only to tramadol is not common; more often the poisoning is due to tramadol in combination with other substances. Reported is a suicidal case of lethal tramadol poisoning in a 48-year-old woman. Tramadol and its metabolites O-desmethyltramadol (M1), N-desmethyltramadol (M2), N,N-didesmethyltramadol (M3), N,O-didesmethyltramadol (M5) were detected by GC/MS in biological fluids (femoral blood, bile, urine, gastric content) and viscera (brain, lung, liver and kidney). The tramadol concentration in femoral blood was 61.83 mcg/ml which is approximately 30 times higher than that believed to be lethal. According with other Authors, a preferential formation of M1 over M2 (M1/M2 ratio >1) is indicative of acute death, while M1/M2 ratio <1 suggests that death occurred after a longer time lapse from ingestion.

A Fatality Involving Clothiapine and Clomipramine

A fatality resulting from the suicidal ingestion of clothiapine, clomipramine and biperiden is reported. Clomipramine, its metabolite N-desmethylclomipramine and clothiapine were quantified in blood, liver, kidney and gastric contents by HPLC and GC. Biperiden was detected only in the gastric content. Significant differences of drug levels were found in postmortem blood obtained from brain and from heart. Concentrations of clomipramine and N-desmethylclomipramine ranged from 0.48 to 1.61 mg/L and 0.26 to 1.32 mg/L, respectively, and clothiapine from 0.50 to 2.15 mg/L. This phenomenon may reflect a postmortem drug redistribution.

Domino effect: An unusual case of six fatal hydrogen sulfide poisonings in quick succession

Hydrogen sulfide (H2S) is one of the most serious toxic gases encountered in forensic practice. Aside from being a by-product of many industrial processes, this gas is naturally produced during the putrefaction of organic substances. We report six autopsy cases of fatal H2S poisonings from inhalation of H2S gas after an occupational accident. These six men died during the unblocking of a wastewater cistern. The first worker died shortly after clearing the obstruction, the other five died, one by one, as they attempted to help their colleagues. The macroscopic and histological findings are discussed here to provide useful information for future cases. Greenish discoloration of the skin and of internal organs (liver, trachea, esophagus, stomach) was observed, and one case showed signs typical of drowning. We present a very unusual incident, complete with rare photographs and toxicological analysis. In these cases, based on both macroscopic and microscopic findings, the cause of death was most likely an inhibitory effect on cellular cytochrome oxidase causing respiratory failure.

Levamisole-adulterated cocaine: Two fatal case reports and evaluation of possible cocaine toxicity potentiation

Levamisole has been identified as a cocaine adulterant in the United States since 2002. Although there is a variation in the percentage of levamisole in cocaine samples between European countries, measurement of levamisole in human samples of cocaine users has become increasingly important. To our best knowledge, only five deaths are reported (one twice) as a result of complications secondary to levamisole-tainted cocaine and none of these cases reports the post-mortem levamisole concentration. In this article, we present the post-mortem levamisole concentrations in fluids and tissues in two young cocaine users, dead after levamisole-adulterated cocaine intake. With the dearth of levamisole reported concentrations in literature, this particular report is of interest to the forensic toxicological and pathological communities. This article aims to be a supplementary alert to aware the risk that may occur using levamisole-adulterated cocaine and an incentive to publication of toxicity reports and new researches involving the combination of levamisole and cocaine.

A fatal accidental subarachnoid injection of lidocaine and levobupivacaine during a lumbar paravertebral block

Paravertebral block (PVB) is the technique of injecting a local anesthetic solution alongside the vertebral column, close to where the spinal nerves emerge, resulting in unilateral somatic and sympathetic nerve blockade. Here is reported a fatal case involving a 60-year-old woman with spondylitis arthropathy, who developed cardiac and respiratory arrest 40min after receiving an accidental subarachnoid injection (L5-S1 bilaterally) of depomedrol lidocaine and levobupivacaine. A complete autopsy including histological and toxicological analyses was performed in order to establish the cause of death. Liquid/liquid extraction (LLE) and GC-MS analysis were performed according to a previously published method. Lidocaine and bupivacaine were detected both in blood, at concentrations of 14.8mg/L and 13.3mg/L respectively, and in cerebrospinal fluid (CSF) at concentrations of 287.1mg/L and 464.2mg/L respectively. Both lidocaine and bupivacaine were also detected in the urine. The toxicological findings along with the autopsy allowed us to establish that the accidental subarachnoid injection of lidocaine and levobupivacaine had led to a progressive hypotension and normovolaemic shock caused by a severe ganglionic block, determining the patients death.