Drugs-of-abuse testing in urine: statistical approach and experimental comparison of immunochemical and chromatographic techniques.

This study deals with the experimental and statistical comparison of six immunochemical techniques, including noninstrumental on-site and instrumental formats (EIA-EMIT and EZ-SCREEN; FPIA-ADx; RIA-Coat-A-Count; LI-Abuscreen ONTRAK; CBI-Triage), and three chromatographic techniques (TLC-Toxi-Lab; HPLC; HPLC-REMEDi drug profiling system), using GC-MS as a reference technique for analyzing amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, methadone, and opiates in the urine of various kinds of drug users. The study reports (a) the values of sensitivity, specificity, false-positive rates, and false-negative rates of each technique; (b) the results of bayesian statistical analysis, which are based on prevalence values of the samples examined and expressed as positive and negative predictive values and cumulative predictive values for each single technique and for combinations of paired immunochemical and chromatographic techniques; and (c) the results of a rough classification of the various degrees of predictability of these techniques. Lastly, this study proposes a decision-making process for establishing the best combination of analytical techniques for the goals in question, according to the characteristics and facilities of each laboratory.

[Analysis and evaluation of blood alcohol values found in victims of fatal traffic accidents in the Parma region (1982-1986)]. / Analisi e valutazione dei valori alcolemici riscontrati nelle vittime degli accidenti mortali del traffico nel territorio parmense (1982-1986).

The Authors examined the relationship between blood alcohol levels and traffic accident incidence in 340 cases which came under the observation of the Institute of Forensic Medicine from 1982 to 1986. Positive blood alcohol (31.2% of cases) were correlated to age, sex, type of vehicle driven, day and hour of the accident and to influence upon behaviour (greater than or equal to 0.50 g%) and to drunkenness (greater than or equal to 1.50 g%). Positive blood alcohol resulted to be correlated to, in the following order, passengers, drivers, pedestrians, motorcyclists and cyclists. The incidence was also related to evening and night hours, and to the days Saturday, Sunday and Monday. Our results, even if not completely superimposable, from a statistical point of view, do permit a comparison between them and those found in the Literature regarding the casuistry of other forensic anatomo-pathologic studies that define the risk factors related to alcohol consumption and traffic accident risk.

Death caused by ingestion of endosulfan.

This paper reports the autopsy and toxicological findings of a death caused by ingestion of endosulfan dispersed in a colorless liquid containing about 55% of xylene (w/v). For isolation of endosulfan, the biological material was homogenized and the drug was isolated by extraction with ether. Quantitative determinations were carried out by gas chromatography. The following concentrations of endosulfan were found: Blood 30 mg/L Gastric contents 0.5 g in the total 50 mL Liver 20 mg/kg Kidney 2.0 mg/kg Brain 0.3 mg/kg Xylene (solvent) was detected only in stomach contents (0.4 g in the total 50 mL).

[High performance thin-layer chromatography in specific blood diagnosis (author's transl)]. / Applicazione del metodo cromatografico radiale (HPTLC) nella diagnosi specifica di sangue

Furthering their research into the differentiation of various haemoglobins (both human and animal) with the use of thin layer chromatographic methods, the Authors have applied Kaiser's high performance thin layer chromatography (HPTLC) to the specific diagnosis of blood. Although the method was superior to ascending one-dimensional thin layer chromatography for its sensitivity, Rf reproducibility and much briefer migration times, it did not turn out to be suitable for application to the specific requirements of forensic haematology.

[Determination of the retention indices (Rf) of hypnotic and anticonvulsant sedatives by thin layer chromatography using Merck silica gel plates (author's transl)]. / Determinazione degli indici di ritenzione (Rf) di sedativi ipnotici ed anticonvulsivanti in cromatografia su strato sottile (TLC) mediante utilizzazione di piastre Merck al gel di silice

In view of the sometimes considerable differences between absolute retention indices (Rf) given in the literature even with the same solvent, same type of adsorbent layer and same operating temperature, the Author proposes the adoption of a standard method derived from the analytical repeatability of Rf values on a thin layer; this would provide a means of searching for a specific parameter by which to identify whole categories of drugs, classified according to their primary therapeutic activity. The study here covers numerous items in the category of hypnotic and anticonvulsant sedatives (barbiturates, non-barbiturate hypnotic drugs, hydantoins, suxinimides, and anticonvulsant agents with various different structures.

[On fatal case acute ethyl alcohol poisoning (author's transl)]. / Su un caso di morte da avvelenamento acuto da alcool etilico

A fatal case was reported of acute intoxication with ethyl alcohol, in which the alcohol levels were higher than any previously reported by Italian workers. On the basis of the normal blood alcohol curve patterns, in the case in question the absorption phase must have lasted longer than the hours usually considered as maximum for absorption of ethyl alcohol.

[Ascending one-dimensional thin layer chromatography in specific blood diagnosis (author's transl)]. / Il metodo cromatografico su strato sottile monodimensionale ascendente nella diagnosi specifica di sangue

A brief review of the literature on chromatography in forensic haematology is followed by a report of the results obtained by using ascending one-dimensional thin layer chromatography in specific blood diagnosis.