[Unified gas chromatography method for the detection of volatile toxicants in biological samples]. / Unifitsirovannyi gazokhromatograficheskii metod opredeleniia letuchikh toksikantov v biomateriale.

A method was designed to identify and quantify the volatile toxicants in cadaveric samples; it is based on analyzing the equilibrium of the gas-vapor phase. A system comprising 3 gas chromatography columns with different polarities and without preliminary isolation of an analyzed substance is used in toxicants' identification. 0.2% n-propanol solution was used in quantification of fresh biological samples, while methanol solution was used in cases of purulence-affected materials. The method sensitivity provides for detecting some of the toxicants, like acetaldehydes, acetone as well as ethyl and higher alcohols at the level of their natural content. The method has been tested for as long as 15 years at expertise objects.

[Forensic and chemical determination of methane in cadaveric samples]. / Sudebno-khimicheskoe opredelenie metana v trupnom materiale.

Conditions were elaborated for the determination of methane, through gas chromatography, in blood and the lung by using a 2% methanol solution as an internal standard and with the below gas-chromatography column being applied: dimensions--200 x 0.3 cm, 15% di-2-ethylhexyl sebacate on Dinochrome II (0.16 x 0.21 mm) at 110 0 degree C. The detector is of the flame-ionization type. The normal content of methane was determined for blood and for the lung--0.122 +/- 0.0074 microgram/ml and 0.20 +/- 0.04 microgram/g, respectively. Biological samples from cadavers of other persons who died due to trauma were suggested for use as controls. The method was used to examine expertise objects, blood and the lung from the cadavers of peoples who died in fire.

[Gas chromatography in quantitative analysis of hydrocyanic acid and its salts in cadaveric blood]. / Gazokhromatograficheskii metod kolichestvennogo opredeleniia sinil'noi kisloty i ee solei v trupnoi krovi.

A direct gas chromatography method was designed for the quantitative determination of cyanides (prussic acid) in cadaveric blood. Its sensitivity is 0.05 mg/ml. The routine volatile products, including substances, which emerge due to putrefaction of organic matters, do not affect the accuracy and reproducibility of the method; the exception is H-propanol that was used as the internal standard. The method was used in legal chemical expertise related with acute cyanide poisoning (suicide) as well as with poisoning of products of combustion of nonmetals (foam-rubber). The absolute error does not exceed 10% with a mean quadratic deviation of 0.0029-0.0033 mg.

[Preservation of methanol in cadaveric material]. / Sokhraniaemost' metilovogo spirta v trupnom materiale.

Duration of preservation of methanol in cadaveric material at 20 +/- 3 degrees C during 4-13 months was studied on 19 model and expert objects of cadaveric material (muscle tissue, kidney, blood, urine). Exponential relationship between methanol concentration and duration of storage of the object was detected. Methanol concentration decreased by 30-70% during the first weeks, after which the process decelerated to 5-10% a month. Toxicologically significant concentrations of endogenous methanol were not revealed in any case.

[Forensic chemical testing of cadaveric material for acetonitrile]. / Sudebno-khimicheskoe issledovanie trupnogo materiala na atsetonitril.

Gas chromatographic conditions for qualitative and quantitative evaluation of acetonitrile in biological material were determined, including those for reactive gas chromatography. Absolute and relative time of acetonitrile and concomitant substances retention in three columns of different polarity was determined. Study of the time of acetonitrile retention in biological material showed that acetonitrile concentration in the blood virtually did not change in cadaveric material stored in a hermetically closed flask for 2 weeks at 20 +/- 3 degrees C, while its concentration in the stomach decreased by 10-15%. Distribution of acetonitrile in human viscera in lethal poisoning was studied; the agent was evenly distributed in the gastric wall, intestine, liver, and kidney, while its concentrations in the lung and brain were 2-3 times higher. Forensic chemical expert analyses of the blood, urine, and viscera from corpses of humans dead from lethal acetonitrile poisoning showed that lethal concentration in the blood was 28.3-57.0 mg and in the urine 23.2-40.6 mg/100 ml.

[Detection of chlorinated carbohydrates in putrefactive biological material]. / Obnaruzhenie khlorproizvodnykh uglevodorodov v gnilostno-izmenennom biomateriale.

Carbochlorohydrates were separated from putrefaction products of organic substances and volatile solvents by gas chromatographic column packed with CaA 5 A. A 100 x 0.4 cm column, used for forensic chemical analysis of fresh and putrefactive cadaveric material, proved to be highly effective. The data were confirmed by results of chemical analysis of distillates from the viscera.

[Gas chromatographic method of quantitative determination of carbon monoxide in cadaver blood]. / Gazokhromatograficheskaia metodika kolichestvennogo opredeleniia okisi ugleroda v krovi iz trupa.

A gas chromatographic method has been developed for measurement of carbon monoxide in cadaveric blood on a chromatographer with thermal conductivity detector and air oxygen as the internal standard. The error of the method is no more than 4% with the mean quadratic deviation +/- 0.18-0.33 min. The method was studied on 10 model and 30 expert blood samples. Putrefactive products did not influence the accuracy of analysis.

[Expert significance of evaluating volatile non-metal combustion products in analysis of blood from subjects dead in fire]. / Ekspertnoe zhachenie opredeleniia letuchikh produktov goreniia nemetallicheskikh materialov pri issledovanii krovi pogibshikh na pozhare.

Qualitative and quantitative composition and time course of formation of toxic substances during burning of polymers have been studied for two polymers, P-53-P and STBO. The most toxic gaseous products of nitrogen combustion are listed: hydrogen cyanide, nitrites, acid nitriles, aldehydes, aromatic carbohydrates, alkanes, and carbon oxide. Two expert conclusions are presented, including analysis of blood and viscera from subjects who died during fire. The following toxic substances were detected: carbon oxide, hydrogen cyanide, nitrites, acrylonitrile, acetonitrile, benzene, and methane in one case and the same products except carbon oxide in the other. The author considers that the list of tested toxic substances should be extended, particularly in cases with negative results of blood testing for carbon oxide and carboxyhemoglobin.

[The gas chromatographic detection of acetylene in cadaveric material]. / Gazokhromatograficheskoe obnaruzhenie atsetilena v trupnom materiale.

Acetylene traces were detected by gas chromatography in the cadaveric right crural muscle of a 30-year-old man dead from an explosion of an acetylene reservoir at a plant. Acetylene was identified using the absolute calibration method on 3 standard gas chromatographic columns, reaction gas chromatography, and acetylene "deduction" by silver sulfate on silicagel.

[A gas chromatographic method for detecting nitrites in the blood and stomach contents]. / Gazokhromatograficheskii metod obnaruzheniia nitritov v krovi i soderzhimom zheludka.

Ethyl nitrite method is proposed as the tentative test for nitrites in studies of the blood and gastric contents. The sensitivity of the method in "pure" solutions is 17 micrograms/sample. The method is specific and its sensitivity is not inferior to routine chemical analyses of biological materials for nitrites.

[The development of the conditions for the direct gas chromatographic determination of ethyl alcohol in cadaveric material]. / Razrabotka uslovii priamogo gazokhromatograficheskogo opredeleniia étilovogo spirta v trupnom materiale.

Conditions for direct gas chromatographic analysis of ethyl alcohol using a device with flame ionization detector have been developed. The presence of other C1-C5 alcohols or alcohol surrogates (acetone, aromatic carbohydrates, organochlorine compounds) did not impede ethanol measurement. Comparison of the accuracy and reproducibility of the routine ethylnitrite and the new direct gas chromatographic analyses showed that the two methods are similar by their metrological parameters and time needed for the measurement. At the same time, use of direct (without ethanol derivation) analysis helps eliminate the contamination of the working area with harmful gases, including nitrogen oxide and alkylnitrites. The above methods of analysis were used with various objects of expert evaluation, including putrescent organs and tissues. Putrefaction products did not influence the accuracy and reproducibility of ethanol measurement.

[Device for calibration of gas-analytical apparatus in the analysis of organochlorine compounds]. / Ustroistvo dlia kalibrovki gazoanaliticheskoi apparatury pri analize khlororganicheskikh soedinenii.

Epoxy resin- and polymethylometacrylate-based polymeric matrices in the device for calibration of gas analytical equipment for analysis of organochlorine compounds are compared. Use of an organochlorine substance solution in polymethylmetacrylate matrix as a generator of these substances microconcentrations helps prolong the period of the device service to 15 months if the deviations of the concentrations from their mean value are up to 10%. An optimal composition of a polymethylmetacrylate-based matrix is offered.

[A device for calibration of a gas chromatograph in analysis of aromatic hydrocarbons]. / Ustroistvo dlia kalibrovki gazovogo khromatografa pri analize aromaticheskikh uglevodorodov.

The article deals with the description of elaborated device for calibration of gas chromatograph in analysis of aromatic hydrocarbons in various media. The device includes a polymeric pattern based on epoxy resin, consolidated by polyethylene polyamine freezing. The authors suggested and tested an optimum composition of aromatic hydrocarbons inserted into the polymeric pattern. The suggested device was proved to maintain the stable calibration of gas chromatograph within at least 1.5 years while the existing concentrations of aromatic hydrocarbons deviate 3.5-7.5% from the average value during 3 months of permanent work.

[Use of temperature coefficients of Kovach indexes in the identification of barbiturates]. / Primenenie temperaturnykh koéffitsientov indeksov Kovacha dlia identifikatsii barbituratov.

The conditions of direct gas chromatographic assessment of barbiturates in reference solutions and cadaveric material extracts were analyzed with the aim of their unification. Along with the Kovach indexes, their temperature coefficients seem promising for the identification of barbiturates. Critical parameters of the evaporator temperature regimen were established, that may be used for barbiturate identification as well. The threshold values of gas chromatographic detection of phenobarbital, barbital, etaminal, hexenal, quietal, and hexobarbital were determined.

[Express method of laboratory study of the outgassing of thermostable plastics and rubbers]. / Ekspress-metod laboratornogo issledovaniia gazovydeleniia termostoikikh plastikov i rezin.

Time-temperature dependence of concentrations of outgasing products of polymers and rubbers was studied. Applying the principle of time-temperature equilibrium, the exposure time for a laboratory rapid study of polymers at 100 degrees C was estimated to be 1 hr for enamels, lacquers and dyes, 1.5 hr for block and sheet polymers, 2.5 hr for sealants and rubbers, and 4 hr for textile materials, measured from the time when the preassigned temperature was achieved. The rapid method can be recommended for preliminary chemical study of polymers at the stage of their laboratory testing.