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The dynamics of the endogenous production of NO metabolites, nitrites, nitrates, and volatile nitrosamines, has been investigated in the body, a tumor tissue, and peritoneal macrophages of mice F1 (C57Bl × CBA), Balb/c and BDF with subcutaneously transplanted tumors: Ehrlich carcinoma (EC) and Lewis metastatic lung carcinoma (LC). It has been shown that during the first three weeks, growth of EC is accompanied by a statistically significant increase in the total concentration of NO metabolites (NOx; nitrites + nitrates) up to levels (7.3 ± 3.49) × 10−6−(7.8 ± 2.57) × 10−5 mol/kg in the tumor tissue and a sharp increase in NOx excretion with urine. At the same time, in the LC tumor tissue the maximal level of NOx (3.6 ± 0.46) × 10−5 mol/kg was registered on day 7, and later it decreased demonstrating negative correlation with the tumor mass. At the stage of intensive LC growth (14, 21 days) there was significant inhibition of nitrite secretion by peritoneal macrophages. In all the controlled time-intervals the EC tumor tissue contained carcinogenic N-nitrosodimethylamine and N-nitrosodiethylamine; however, their concentrations significantly varied. Thus, the ability of the tumor tissue to produce NO metabolites was more pronounced in EC than in LC and depended on the time parameters of tumor growth.

The endogenous formation of metabolites of NO - nitrite (NI), nitrates (NA) and volatile nitrosamines in the body, tumor tissue and by abdominal cavity by macrophages for dynamics was investigated in mice F1(C57BlxCBA), Balb/c and BDF with subcutaneous transplanted tumors (Erlich carcinoma - EC and metastatic Lewis lung carcinoma - LLC). It was shown that growth of EC was accompanied by a statistically significant increase in the concentrations of NI and NA in tumor tissue to (7.3±4.67)'10-6 - (7.8±2.57)'10-5 (mol/kg) for the first three weeks and a sharp increase in urinary excretion of NI and NA. The maximum total concentration of NI and NA - (3.,6±0.46)'10-5 in tissue LLC was registered during the early stage of the tumor growth (7 days); it later declined, negatively correlating with the mass of the tumor. NI secretion by abdominal cavity macrophages demonstrated statistically significantly decrease at the stage of intensive growth LLC (14, 21 days). The tissue of EC contained varied concentration of cancerogenic N-nitrosodimethylamine and N-nitrosodiethylamine at all investigated time points. Thus, the ability of different gistogenesis tumor tissue to synthesize metabolites NO depended on time parameters and was more pronounced for EC, than LLC.V issledovaniiakh na myshakh F1(C57BlxCBA), Balb/c i BDF s podkozhno perevitymi opukholiami (kartsinoma Érlikha – KÉ i metastaziruiushchaia kartsinoma legkikh L'iuisa – KL) izuchena dinamika éndogennogo obrazovaniia metabolitov NO – nitritov (NI), nitratov (NA), letuchikh nitrozaminov v organizme, v opukholevoĭ tkani i peritoneal'nymi makrofagami. Pokazano, chto rost KÉ v techenie pervykh trekh nedel' soprovozhdaetsia statisticheski znachimym uvelicheniem summarnoĭ kontsentratsii NI+NA v opukholevoĭ tkani do urovneĭ (7,3±4,67)´10-6 – (7,8±2,57)´10-5 (mol'/kg), a takzhe rezkogo uvelicheniia vydeleniia NI+NA s mochoĭ. V to zhe vremia, v opukholevoĭ tkani KL maksimal'nyĭ uroven' kontsentratsii NI+NA (3,6±0,46kh10-5) registrirovali na 7-e sutki, v dal'neĭshem on snizhalsia, otritsatel'no korreliruia s massoĭ opukholi. Na étape intensivnogo rosta KL (14, 21 sutki) obnaruzheno dostovernoe podavlenie sekretsii NI peritoneal'nymi makrofagami. Na vsekh kontroliruemykh srokakh razvitiia opukholevaia tkan' KÉ soderzhala kantserogennye N-nitrozodimetilamin i N-nitrozodiétilamin, kontsentratsiia kotorykh sushchestvenno var'irovala. Takim obrazom, sposobnost' opukholevoĭ tkani sintezirovat' metabolity NO bolee vyrazhena u KÉ, po sravneniiu s KL i zavisit ot vremennykh parametrov rosta opukholeĭ.

A method was described for determining polycyclic aromatic hydrocarbons (PAHs) and their nitro derivatives (nitro-PAHs) in samples of complex composition using low-temperature luminescence. Fractionation by HPLC was used to separate compounds with similar spectral properties. At the chromatograph inlet, a test sample was purified from weakly retained components additionally preconcentrated on a concentrator cartridge, which was fixed in the injector in place of the sampling loop. Step gradient fractionation was considered, and a table of retention times for PAHs and nitro-PAHs was presented. The the fractional distribution of the analytes was studied. Phosphorescence spectra of some nitro-PAHs were described. The method proposed is comparable in sensitivity to HPLC with the fluorescence detection, but does not require derivatization for determining nitro-PAHs. A table of spectral parameters of analytes suffices for qualitative analysis, as in chromatography–mass spectrometry. However, in distinction to the latter technique, the method described is selective because of the specificity of excitation and emission spectra of each of the analytes.

The authors performed investigations of the content of polycyclic aromatic hydrocarbons (PAH) (n = 17) and their nitro derivatives (n = 5) in commercial cold and hot smoked herrings and greenlings. The level of benz(a)pyrene in all fish samples was found to be well below the current sanitary and hygienic limits. The concentration of N-nitrosoamines in cold smoked fish was slightly below that in hot smoked one. The content of nitro derivatives of PAH in fish is indicative of the low significance of these compounds in the total negative potential of smoked fish.

The investigation deals with an assessment of carcinogenicity and mutagenicity of samples of smokeless tobacco now on the Russian market as well as ash from alternative cigarettes made of aromatic herbs. Our data showed that the levels of polycyclic aromatic hydrocarbons, volatile and tobacco-specific N-nitrosoamines complied with the standards in the producer-countries. Smokeless tobacco extracts failed to show (Ames) any mutagenic effects such as the "read-out frame shift" or "base-pair replacement" patterns. No tobacco-specific N-nitrosoamines were identified in herbal cigarettes. However, polycyclic aromatic hydrocarbons and volatile N-nitrosoamines content appeared to be identical to that of tobacco. Herbal cigarette smoke extracts mutagenicity induced by side-effects of carcinogenic substances was of similar magnitude as well.

The composition and contents of major N-nitrosoamines (NA) in the edible part of herrings and rock trouts exposed to hot and cold smoking and in the Smoked fish in oil type cans were studied. Among NA, only N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) were detected in all samples. In the cold-smoked fish, the levels of NDMA and NDEA were higher than in the hot smoked fish and cans. Of all the samples, only those of cold smoked herrings and rock trouts had standardized NDMA concentration that was greater than the standard limitation and equal to 3.48 and 3.74 mukg/kg.

The disperse phase of waste fumes forming during cold and hot fish smoking was studied by distributing the particles into 6 fractions and determining benz(a)pyrene (BP) in them. The level of BP in less than 2.5 mu was shown to be 85% whether smoking was hot or cold. The levels of 17 priority polycyclic aromatic hydrocarbons (PAH) were measured in three-dimensional fractions of fume particles. In all the fractions, phenanthrene and fluoranthene were of priority in weight. The proportion of BP in the total levels of PAH in waste fumes of cold and hot smokers was 0.69 and 0.74%, respectively and the carcinogenic activity was 46.42 and 49.0%. The investigations demonstrated that the waste fumes of smokers did not contain the particles that are PAH carriers.

The carcinogenic danger of the commercial smoked herring was assessed. The edible part of the smoked herring contains 16 polycyclic aromatic hydrocarbons whose bulk consists of phenanthrene, pyrene, floranthene, and benzo(b)fluoranthene. The content of benzo(a)pyrene (BP) in the cold and hot smoked herring are 189 and 291 ng/kg, respectively. It is lower than the present standard values. The proportion of carcinogenic danger of BP is 32% for cold smoked herring and 34% for hot smoked herring.

Moscow is used as an example to discuss the problem of urban atmospheric pollution by carcinogenic N-nitrosamines. An analytical method is proposed, which is based on the use of a Russian gas chromatograph compatible with a chemiluminescence detector, that is a TEA thermal energy analyzer (USA) having some modifications to reduce the time of analysis and loss during sample pretreatment. The minimal detected concentration is 3 ng/m3 for 2-hour sampling. The method identifies and quantifies 7 volatile N-nitrosamines: N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine, N-nitrosodibutylamine, N-nitrosodipropylamine, N-nitrosopiperidine, N-nitrosopyrrolidine, N-nitrosomorpholine. The pollution of the Moscow air was evaluated in the center of Moscow (30-60 ng/m3 for NDMA), in the industrial emission area (as high as several hundred ng/m3, and in the heavy traffic area (100 ng/m3 or more). It is proposed to study the working area for rubber and tire industries, to establish nitrosamine tolerances for these industries and maximum allowable discharge concentrations in the urban air and to monitor these parameters.

The level of volatile carcinogenic N-nitrosamines (NA) was studied in the air of various technological sites of tyre production. Reported total levels of NA in air exceeded MACs set in certain countries for the same enterprises. For example, German total MAC for 12 carcinogenic NA is 1 g/m3. N-nitrosomorpholine appeared to have the highest level (91 g/m3), probably, because its derivatives are used as raw material for technological process. Relative rate of volatile NA release from rubber samples containing 4-nitrosodiphenylamine (modifier) was studied. The parameter was reported to have no influence on NA outlet in conditions simulating technological process. NA was detected by means of gas chromatography with thermal energy detector TEA 502A provided by Thermo Electron Corporation, USA. The article necessitates regulation of NA in tyre production and better rubber mixtures to control the pollution of atmosphere.

Concentrations of benz(a)pyrene (BP) and 15 other polycyclic aromatic hydrocarbons (PAH) in soil with forage plants (lucerne) irrigated by biologically purified mixed domestic and industrial (coke-chemical) sewage from collection pond did not exceed those in control soil (irrigated by relatively clean fresh water) and were lower than in nonirrigated one, which is due, probably, to PAH oxidation by soil-proper microflora activated in humid soil polluted by PAH. BP content in control and experimental samples of lucerne coincide within +/- 25% limits.