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PubMed2002

Determination of polycyclic aromatic hydrocarbons and polycylic aromatic sulfur heterocycles by high-performance liquid chromatography with fluorescence and atmospheric pressure chemical ionization mass spectrometry detection in seawater and sediment samples.

Two methods for determining 10 polycyclic aromatic compounds were developed. Both methods were based on high-performance liquid chromatography (HPLC), but one method used fluorescence detection, while the other used atmospheric pressure chemical ionization mass spectrometry (APCI-MS). For water analysis, solid-phase extraction (SPE) was on-line coupled to the separation system. Using a styrene-divinylbenzene copolymer (PLRP-s) as sorbent in the SPE and adding 20% of acetonitrile to the water sample before its preconcentration, recoveries were above 70% for most of the compounds. For the fluorescence method, all compounds were detected and six of them could be quantified at concentrations higher than 0.02 microg 1(-1). For the MS detection method, only seven of the compounds were detected and six were quantified at concentrations higher than 0.06 microg 1(-1). To analyse sediment samples, an extraction with dichloromethane was used and, due to the complexity of the matrix, a standard addition calibration was carried out. Seawater and sediment samples taken from the Tarragona fishing port and marina on the coast of Catalonia (Spain) were analysed, and five compounds (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) were quantified in the sediment samples.

Atmospheric Pressure↗
PubMedDate not supplied

The genotoxicity of unsubstituted and nitrated polycyclic aromatic hydrocarbons.

To determine the DNA damaging properties of unsubstituted and substituted polycyclic hydrocarbons, 61 aromatic and heterocyclic compounds were examined for the induction of the SOS system in E. coli PQ37. PAH such as benzo[ghi]fluoranthene, benzo[j]fluoranthene, benzo[c]phenanthrene, benzo[a]pyrene, chrysene, dibenzo[a,1]pyrene, fluoranthene and triphenylene showed relatively high genotoxicity. With respect to the nitroarenes, the highest genotoxic potencies were exhibited by the dinitropyrenes. The SOS-inducing potency of nitroarenes increased from the bicyclic to the tetracyclic ring system. Additionally, it was seen that any increase in the extent of nitration is paralleled by an increase of genotoxicity. Whereas PAH required metabolic activation by hepatic cytochrome P-450 enzymes, nPAH were direct-acting genotoxicants.

Animals↗
PubMed1994

Inhibitory activity of chlorophyllin on the genotoxicity of carcinogens in Drosophila.

Antimutagenic activity of copper chlorophyllin against various carcinogenic mutagens was assayed with Drosophila genotoxicity tests, i.e., the wing spot test for detecting somatic cell mutations and the DNA repair test for detecting DNA damage. In these tests, Drosophila larvae were fed carcinogens together with chlorophyllin. Polycyclic aromatic compounds, including heterocyclic amines, polycyclic aromatic hydrocarbons, aromatic amines and aromatic nitro compounds, were subject to inhibition, with a few exceptions. The results support the view that chlorophyllin traps carcinogens by forming complexes, thereby inhibiting the absorption of these compounds from the digestive tract. Consistent with this mechanism, Sepharose-supported chlorophyllin in the feed inhibited the Trp-P-2-induced wing spot formation, while Sepharose itself was ineffective.

Animals↗
PubMed2005

Synthetic musk fragrances in trout from Danish fish farms and human milk.

Synthetic musk compounds used in detergents and cosmetics include nitro and polycyclic musk compounds. These compounds are discharged after use via domestic wastewater and sewage treatment plants to the aquatic environment. Quantitative detection of nitro musk and polycyclic musk compounds by GC/HRMS in Danish farmed trout and human milk from primiparous mothers are reported. The polycyclic musk, HHCB, dominated the synthetic musk compounds found in trout samples from 1999 with a median concentration of 5.0microg/kg fresh weight (n.d.-52.6microg/kg fresh weight) and in trout samples collected in 2003 and 2004 with a median concentration of 1.2microg/kg fresh weight (n.d.-28.0microg/kg fresh weight). It was also found that the concentration of musk xylene in trout sampled at the same fish farms decreased considerably from a median concentration of 5.1microg/kg fresh weight in 1992 to a median of 0.5microg/kg fresh weight in 1999 and to a median less than the detection limit (0.23microg/kg fresh weight) in 2003. HHCB also dominated in Danish human milk samples collected in 1999 with a median concentration of 147microg/kg fat (38.0-422microg/kg fat). Human dietary intake assessment and body burden calculations on data from 1999 indicate that the main source of exposure to human cannot be attributed to the consumption of farmed trout.

Adult↗
PubMed1985

[Polar neutral organic compounds in urban aerosols. 1. Chemical characterization and mutagenic effect in relation to various sources].

Airborne particulate matter was collected by high volume samplers at two sampling stations in Berlin (West) between March 1983 and February 1984 (immissions). The stations were choosen so that two main-sources of urban air pollution could be considered (automobile) traffic and private fuel combustion (domesticfuel). Also in February and March 1983 particles were collected from private coal firing (emissions). The collected particles were fractionated into the following particle sizes (immissions, during October 1983-February 1984): greater than 7.2 microns, 7.2-1.5 microns and less than 1.5 micron (aerodynamic diameter). The etherextractable organic matter of the particles (= EEOM) was determined and the organic matter was then separated into acidic, basic, and neutral fractions. The neutral fraction was further separated into aliphatic compounds (= AlP), polycyclic aromatic hydrocarbons (= PAH), and polar neutral compounds (= POCN) by thin layer chromatography. The mutagenic activity of all organic fractions was determined by using the mammalian microsome bioassay by Ames and was compared with the activity of a whole polar organic extract (including POCN, acidic and basic fraction), a whole neutral extract, and a whole ethersoluble organic extract. Also in February 1984 the nitroreductase specific mutagenicity on immission-stations was determined using nitroreductase deficient strains. Some compounds of the POCN-fraction, and of PAH (in comparison) were identified by gas chromatography. The following results were obtained: The neutral fraction of the organic matter amounted to 70-90% of the EEOM (not depending from particle size, immissions and emissions). The separation of the neutral compounds into AlP, PAH and POCN showed a higher amount of AlP at the collecting station which includes mainly automobile traffic. Some cancer and/or mutagenic suspect compounds were identified by the chromatographic analysis of POCN and PAH. A higher amount of several nitrogroups-containing POCN was found at the collecting station which includes mainly private combustion whereas at the station including mainly automobile traffic 1-nitropyrene was the main compound. The POCN-fraction showed the mostly highest mutagenic activity in the Ames bioassay, mainly for lung penetrating particles (less than 1.5 micron diameter). The whole organic extract (EEOM) showed a lower mutagenic activity than the POCN-fraction. Using nitroreductase deficient strains, at the collecting station which includes mainly private fuel combustion a higher reduction of mutagenicity was shown than at the automobile-traffic including measurement station.

Aerosols↗
PubMed1990

[Pulsed method of sampling in monitoring of carcinogenic substances in gaseous atmosphere].

Experiments using various types of gas samplers showed that application of A phi A type fibrous material-containing filters for benzo(a)pyrene monitoring may result in significant underestimation of the carcinogen level in the air. The authors developed pulsed sampler using suspended layer of sorbent which proved most effective in catching benzo(a)pyrene in gaseous atmosphere. The unit allows simultaneous sampling of carcinogenic polycyclic aromatic hydrocarbons and N-nitroso compounds.

Air Pollutants↗
PubMed1978

[Carcinogens in food (author's transl)].

There is no evidence at present that certain chemicals are responsible for certain human cancers (with the exception of aflatoxin, which is the most suspect agent in the development of primary liver cancer in some districts of Africa and in Thailand). A number of chemicals which are carcinogenic to animals are present in human food. Any chemical which induces tumours in animals should be considered as a potential human carcinogen. But special studies must be undertaken before the role played by these substances in the development of human cancer can be definitely evaluated. First priority should be given to polycyclic aromatic hydrocarbons and N-nitroso compounds by reason of their general distribution in the human environment and their high efficiency in animal experiments. An appropriate approach to such studies would be the establishment of correlations between cancer morbidity data and the data on levels of these chemicals in special environments and, if possible, their total intake. This approach has proved fruitful in the aflatoxin intake studies carried out in countries where liver cancer is endemic. The IARC is currently carrying out a study of this kind in areas of high oesophageal cancer morbidity in Iran and in the north of France.

Carcinogens↗
PubMed1988

[Polar neutral organic compounds (POCN) in city aerosols. 3. Comparative studies of emission and immission particles in West Berlin].

After the concentration of the polar organic compounds (= POCN), especially from the neutral fraction, was investigated in urban suspended particulates over a longtime period in Berlin (West) (March 1983-January 1984 at three emission measurement stations loaded by different sources) and some emissions were taken during 1985 from vehicle diesel-engines and private coal firing (domestic fuel) a comparison between all these measurements are given now. The following results were gained: The amount of the ether-extractable organic matter (= EEOM) was higher for the emission samples (less than or equal to 80% of the total suspended particulate matter = TPM) than for the emission measurements (less than or equal to 40% of the TPM). Most of the EEOM was found for particle sizes less than or equal to 1.5-2 micron aerodynamic diameter. Making further separation of the EEOM, then the neutral fraction (= NF) showed the highest percentage of about 60-90% (of the EEOM) for emission measurements and of 60-80% for emission measurements. The values of the acidic fraction (= AF) were with 5-30% (emissions) and 10-25% (emissions). Quite the same results were found for the basic fraction (= BF) with 1-20% (emissions) and 5-20% (emissions). Of the neutral fraction, further separation was done into aliphatic compounds (= AIP), polycyclic aromatic hydrocarbons (= PAH) and polar neutral organic compounds (= POCN). From these compounds, the aliphatics amounted to 30-40% (of the NF) for the vehicle emission measurements and to only 10-20% for the coal firing emissions. The percentages of the PAH and POCN varied and were quite similar with 10-50% (PAH) and 25-50% (POCN). For the emission measurements, the PAH amounted to lower values (5-30%) and the POCN to (30-60%). Some differences between the measurements were found in the gas chromatographic analysis of single PAH and POCN compounds. Then, for the vehicle samples (diesel engines and highway traffic tunnel) higher concentrations were found for perylene and coronene (of the PAH) and for mainly 1-nitropyrene (of the POCN) in comparison with coal firing emissions. There, we found higher concentrations for phenanthrene, benzo(a)pyrene and dibenz(a,h) anthracene (of the PAH) and for 9-fluorenone (of the POCN). The concentration of the nitro-groups containing substances (included in the POCN-fraction) amounted here generally to higher values in comparison with the vehicle emissions (except of 1-nitropyrene).(ABSTRACT TRUNCATED AT 400 WORDS)

Air Pollutants↗
PubMed1981

The role of nitroaromatic compounds in the direct-acting mutagenicity of diesel particle extracts.

The Salmonella mutation assay has been adapted to a number of experimental procedures used to characterize the chemical components and molecular mechanisms involved in the direct-acting mutagenicity of diesel particle extracts. The mutagens were found to be unreactive towards purified DNA. Mutagenic activity was decreased in nitroreductase-deficient bacteria and increased in the absence of oxygen, suggesting that bacterial enzymes active the mutagens. The extract was fractionated by thin layer chromatography using both normal and reverse phase silica gel plates. On normal silica plates, a separation was made between unsubstituted PAH, nitro-PAH and the more polar aromatic compounds. About a third of the mutagenic activity in the particle extract was recovered in fractions containing monosubstituted nitro-PAH compounds. The absorption spectra and reverse phase chromatographic properties indicate 1-nitropyrene is a predominant component but not the only mutagen in these fractions. The remaining activity was in the more polar fractions, and mutagenicity assays using anaerobic conditions and nitro-reductase-deficient bacteria suggest they contain other nitro-substituted compounds.

Air Pollutants↗
PubMed1990

Sensitive method for the detection of mutagenic nitroarenes and aromatic amines: new derivatives of Salmonella typhimurium tester strains possessing elevated O-acetyltransferase levels.

Acetyl-CoA: N-hydroxyarylamine O-acetyltransferase is an enzyme involved in the intracellular metabolic activation of arylhydroxylamines derived from mutagenic nitroarenes and aromatic amines. The acetyltransferase gene of Salmonella typhimurium TA1538 was cloned into pBR322 and the plasmids harboring the gene were introduced into TA98 and TA100. The resulting strains (YG1024 and YG1029) had about 100 times higher 2-hydroxyamino-6-methyldipyrido[1,2-a:3',2'-d]-imidazole (N-hydroxy-Glu-P-1) O-acetyltransferase activity than TA1538 containing pBR322, and were extremely sensitive to the mutagenic actions of 2-nitrofluorene, 1-nitropyrene, 1,8-dinitropyrene, 2-amino-6-methyldipyrido[1,2-a:3',2-d)-imidazole (Glu-P-1), 2-aminofluorene and 2-aminoanthracene. These results indicate that the new strains permit the efficient detection of the mutagenicity of environmental nitroarenes and aromatic amines.

Acetyltransferases↗
PubMed1985

Activation and inactivation of a variety of mutagenic compounds by the reconstituted system containing highly purified preparations of cytochrome P-450 from rat liver.

Six cytochrome P-450 preparations from phenobarbital (PB)-treated rats and two preparations from beta-naphthoflavone (BNF)-treated rats were purified. Using Salmonella typhimurium TA98 the ability of these cytochrome P-450 preparations to mutagenically activate and inactivate a variety of carcinogens was examined. High- and low-spin forms of cytochrome P-448 isolated from BNF-treated rats (BNF-IIa and IId) activated various carcinogens. Both forms activated 2-aminofluorene, benzo[a]pyrene, and dibenz[a,c]anthracene. However, o-aminoazotoluene and 2-nitrofluorene were activated only by the low-spin form, and aflatoxin B1 only by the high-spin form. In contrast, only limited carcinogens were activated by some preparations from PB-treated rats. 2-Aminofluorene was activated by four PB-inducible preparations (PB-Ia, Ic, Id, and IIa), but only moderately. Unexpectedly, however, the most prominent activation of benzo[a]pyrene was observed with one preparation (PB-Id) from PB-treated rats. Direct mutagens to the S. typhimurium, 4-NQO and AF-2, were markedly inactivated by NADPH-cytochrome c (P-450) reductase without cytochrome P-450. One PB-inducible form (PB-Ic) inactivated 2-nitrofluorene, and the high-spin form of P-448 (BNF-IIa) inactivated AF-2.

Aflatoxin B1↗
PubMed2004

Preparation and characterization of a p-tert-butyl-calix[6]-1,4-benzocrown-4-bonded silica gel stationary phase for liquid chromatography.

A p-tert-butyl-calix[6]-1,4-benzocrown-4-bonded silica gel stationary phase (CR6BS) was first prepared via 3-glycidoxypropyltrimethoxysilane as coupling reagent for high performance liquid chromatography. The structure of the new stationary phase was characterized by diffuse reflectance infrared fourier transform spectroscopy (DRIFT), elemental analysis and thermal analysis. The chromatographic performance of the bonded-stationary phase was evaluated by using neutral, acidic and basic solutes as probes. Meanwhile, comparative study of the new stationary phase with a p-tert-butyl-calix[6]arene-bonded silica gel stationary phase (C6BS, the parent) and ODS was done under the same chromatographic conditions. The results show that the new stationary phase has an excellent reversed-phase property, which is similar to C6BS and ODS. However, the selectivities for some aromatic compounds are different from the parent phase (C6BS) and ODS, especially the latter. In one hand, as hybrid of calixarene and crown ether, CR6BS with the oxygen atoms of ether-bridge can provide the complexation sites for the solutes, lacking of C6BS. On the other hand, the rigid conformation of CR6BS may be responsible to the different performance partially. CR6BS exhibits high selectivity in the separation of alkylated aromatics from their parents as compared with C6BS.

Aniline Compounds↗
PubMed2005

Temperature-programmed retention indices for gas chromatography-mass spectroscopy analysis of plant essential oils.

A total of 95 volatile compounds from the essential oil in buds of Syringa oblata Lindl (lilac) were identified by gas chromatography-mass spectrometry (GC-MS) combined with heuristic evolving latent projections (HELP) and moving subwindow searching (MSS). The identified compounds are mainly aliphatic, terpenes and aromatic compounds. Their temperature-programmed retention indices (PTRIs) on HP-5MS and DB-35MS at three heating rates of 2, 4 and 6 degrees C/min from 80 to 290 degrees C were obtained, which showed that aliphatic compounds give nearly constant PTRIs and PTRIs of terpenoids do not vary much at different heating rates. But PTRIs of aromatic compounds exhibit relatively large temperature dependence. PTRIs vary much more on DB-35MS than those on HP-5MS according to the compound types. In general, differences of PTRIs between the two columns increase from aliphatic compounds to terpenoids to polycyclic aromatic compounds. The PTRIs in different heating rates were used as cross-references in the identification of components in the essential oil. When they were used in analysis of essential oil from flowers of lilac, good results were obtained. These PTRIs would be a part of our PTRI database being constructed on components from plant essential oils. The results also showed that efficiency and reliability were improved greatly when chemometric method and PTRIs were used as assistants of GC-MS in identification of chemical components in plant essential oils.

Flowers↗