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1.
Detection of PAH of six benzene rings is somewhat troublesome and lowering the limits of detection (LODs) for these compounds in food is necessary. For this purpose, we optimized a Programmable-Temperature-Vaporisation (PTV) injection with Large Volume Injection (LVI) with regard to the GC-MS detection of anthracene, benz[a]anthracene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene and dibenzo[a,e]pyrene. The optimization of PTV-LVI for GC-MS analysis included the choice of liner, solvent venting, splitless time, split flow and initial inlet temperature for injection of 25 μ L standard solution and spiked mussel samples. Samples were extracted with Accelerated Solvent Extraction (ASE) followed by two semi-automatic clean-up steps; gel permeation chromatography (GPC) on S-X3 and solid phase extraction (SPE) on pre-packed silica columns, prior to gas chromatography-mass spectrometry (GC-MS) detection. In comparison to traditional splitless injection, LODs were lowered for eighteen PAHs by the use of PTV-LVI ranging from 0.05 μ g kg ?1 to 1.0 μ g kg?1 fresh weight. In particular, the LOD of dibenzo[a,e]pyrene was improved by a factor of ten when using the validated PTV-LVI method.  相似文献   

2.
Exposure of mammalian cells to polycyclic aromatic compounds (PACs) such as the carcinogen benzo[a]pyrene (BaP) leads to the formation of DNA adducts N2-deoxyguanosine (dG) and N6-deoxyadenosine (dA) with adenine and guanine nucleotides, which are integral parts of DNA, RNA, and ATP. DNA adduct formation causes alteration of the DNA (RNA) sequence since neither adenine nor guanine can normally bind to its complementary nucleotide base, thymine (uracil) and cytosine respectively. The inability to form these bonds leads to mutations in the DNA double-helix structure during DNA replication, and eventually carcinogenesis. Therefore, the capability to detect and measure PAC species such as BaP in single living cells is important for studies required to establish the limits of BaP exposure necessary for carcinogenesis. Along these lines, we have developed antibody-based optical nanoprobes capable of detecting and measuring BaP in single living cells. The results obtained in this work demonstrate the practical application of antibody-based nanoprobes for performing measurements inside single living cells with their elements and their relationships intact.  相似文献   

3.
We evaluated in a pilot study a newly developed method of gas chromatography isotope dilution high-resolution mass spectrometry selected ion monitoring (GC-ID-HRMS-SIM). This method measures benzo[a]pyrene (B[a]P) tetrol metabolites released after albumin-BaPDE adduct hydrolysis. We isolated albumin adducts from the blood of a cohort of adult male and female smokers and nonsmokers randomly selected as exposed and nonexposed groups. Isomeric B[a]P tetrols released after adduct hydrolysis and silyl derivatization were quantified by GC-ID-HRMS-SIM using 13 C 6 -isotopically labeled BaP tetrol isomer standards (+/?)-BaP-r-7,t-8,t-9,c-10-tetrol (BPTI-1), (+/?)-BaP-r-7,t-8,t-9,t-10-tetrol (BPTI-2), (+/?)-BaP-r-7,t-8,c-9,t-10-tetrol (BPTII-1) and (+/?)-BaP-r-7,t-8,c-9,c-10-tetrol (BPTII-2). In all donor samples analyzed the method was sensitive enough to detect BPTII-1 and BPTI-1 in the low fmol range. In both smokers and nonsmokers BPTI-1 levels were higher than BPTII-1 levels. The mean levels of BPTII-1 and BPTI-1 in smokers were 0.16 ± 0.04 fmol/mg albumin (ranging from 0.09 to 0.28 fmol/mg albumin) and 0.40 ± 0.06 fmol/mg albumin (ranging from 0.25 to 0.75 fmol/mg albumin), respectively. The mean levels of BPTII-1 and BPTI-1 in nonsmokers were 0.22 ± 0.07 fmol/mg albumin (ranging from 0.09 to 0.41 fmol/mg albumin) and 0.47 ± 0.06 fmol/mg albumin (ranging from 0.30 to 0.75 fmol/mg albumin), respectively. The results from this study are the first reported quantitative levels of specific benzo[a]pyrene tetrol isomers detected by isotope dilution high-resolution mass spectrometry measurements of BaPDE-albumin adducts using 13 C 6 -isotopically labeled BaP tetrol isomer standards.  相似文献   

4.
Polycyclic aromatic hydrocarbons (PAHs) were previously measured in whole small finfish (< 30 cm) or in the internal organs relative to the rest of tissues, as well as in muscle, liver, and gonads of larger finfish, collected offshore in the Northwest Atlantic. Alkylated naphthalenes (NA) were more abundant than phenanthrenes (PA), while fluoranthene (FL), pyrene (PY), and chrysene (CH) were also detected in some cases. Bioaccumulation pointed to uptake by respiration and, probably by a dietary contribution, especially for benthic species. Therefore, speckled trout were exposed to PA, FL, and PY through food and the parent PAH and their respective metabolites were analyzed. Trout maintained at 10°C were fed daily for 10 weeks with pellets spiked with 0.33–0.38 μg of each PAH per g fish. Muscle, internal organs, and bile of fish were analyzed by HPLC every 2 weeks, for up to 14 weeks. The concentration of PA was always higher than that of FL. No phase I or phase II metabolites were detected for either compound, even in the bile. Concentrations and total tissue burdens were higher in the internal organs than in the muscle for PA and FL. The highest levels of PA equivalent to 5 days' feeding were present in internal organs on week 10. Levels of PY were lower than levels of FL in internal organs and muscle. The amounts of PY-glucuronide in whole gall bladder bile were higher than amounts of PY in any whole compartment. PY-glucuronide was also detected in internal organs. Comparison will be made to a short-term exposure of winter flounder to 5 μg/g of the same three PAHs.  相似文献   

5.
Biomonitoring of workers was carried out in seven workplaces—two aluminium plants, an electrometallurgy plant, two carbon brake disk factories, a creosoting workshop, and an artificial target factory—to assess exposure to polycyclic aromatic hydrocarbons (PAHs). At least all the 48 h voided urine samples were collected, the first urine before the preshift at the beginning of the week and the last one after the preshift of the third day. The 3-hydroxybenzo[a]pyrene (3-OHBaP) and 1-hydroxypyrene (1-OHPy) in each urine sample were then analyzed separately by methods developed by INRS. Concentration profiles were determined. They indicate a considerable lag between the maximum excretion of the two metabolites. Including the previously published data obtained with workers exposed to PAHs, this varies from 3 to 24 h (mean lag = 15 h, n = 42). In order to determine the most appropriate sampling time for 3-OHBaP, the time of the 3-OHBaP maximum concentration is compared with the preshift.  相似文献   

6.
A new calibration solution reference material (NMIJ CRM 4213-a) for benzo[a]pyrene (BaP) analysis was prepared and certified by the National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). Certification of CRM 4213-a was carried out at NMIJ using a freezing point depression method and gravimetric preparation. Certified concentration of this CRM was obtained by multiplying the dilution ratio of raw material BaP in a prepared solution with purity of the raw material. Purity of our raw material was calibrated by a gas chromatograph with flame ionization detection using that of high-purity BaP purified by using a high performance liquid chromatograph with a normal phase column, because purity determination of the raw material by a differential scanning calorimeter (DSC) couldn't be assessed directly. The purity of high-purity BaP was assessed in the molar fraction by DSC, and then the purity of the mass fraction was calculated based on average molecular weight of impurities and the purity of the molar fraction. CRM 4213-a has been developed with a certified value of 99.2 mg/kg. Uncertainty was evaluated from purity assessment as well as homogeneity and stability of the CRM, and expanded uncertainty was estimated as 3.9 mg/kg with coverage factor k = 2, corresponding to an estimated confidence interval of approximately 95%.  相似文献   

7.
Atmospheric and biological monitoring was carried out on 38 people exposed to polycyclic aromatic hydrocarbons in different workplaces. The relationship between the atmospheric BaP and the 3-OHBaP urinary concentration peaks was determined. To avoid misinterpretation due to dermal exposure, only people with mainly respiratory exposure were chosen. The selection was carried out from observation of working conditions and from urinary data. For the limit value determination, BaP concentrations higher than 5,000 ng/m3 were discarded and the 3-OHBaP values were adjusted to a 8 h exposure time. A close relationship was observed between the two variables: n = 17, r = 0.89, p < .0001 (C 3-OHBaP = 0.001835*C BaP + 0.1729). To estimate the 3-OHBaP limit concentration, the French recommended value of 150 ng/m3 for atmospheric BaP was used. The corresponding 3-OHBaP was 0.45 nmol/mol creatinine. This value could be used as a sound basic element for determining a biological exposure index.  相似文献   

8.
The levels of 16 EPA polycyclic aromatic hydrocarbons (PAHs) were investigated in samples of sugar beets and their products representative for a beet sugar factory located in the central part of Vojvodina, the main agricultural region in Serbia. The sum of the detected PAHs ranged from 51 pg g ?1 ww for molasses to 391 pg g ?1 ww for dried sugar beet pulp. The concentration of benzo(a)pyrene (BaP) for all sample types was about or less than 100 pg g ?1 ww, which is far less than the existing Serbian and EU tolerances set for some foodstuffs. The Serbian intake of BaP via total sugar consumption that ranged from 70–85 g per capita day ?1 , was assessed to be from 0.029 to 0.035 ng kg ?1 b.w. day ?1 . Furthermore, the toxic equivalency factor (TEF) approach was used to estimate the carcinogenicity of PAH mixture found in analyzed samples.  相似文献   

9.
Smoke from cigarette smoking and burning of incense sticks and mosquito-repellent incense, which is particularly used in summer, are thought to be primary factors of indoor air pollution by polycyclic aromatic hydrocarbons (PAHs) in Japanese houses. In this study, these respective smokes as indoor air pollutants were evaluated by quantifying their particulate matter (PM) and 7 PAHs. PM and PAHs in smoke from 5 popular brands of Japanese cigarettes were collected on the glass fiber filter by the international smoking mode. PM was quantified by weighing the filter before and after trapping them. PAHs were analyzed by HPLC after extracting the filter with ethanol/benzene (1:3, by vol.). Similarly, evaluation of smoke respectively generated by natural burning of 4 brands of incense sticks and 3 brands of mosquito-repellent incenses was also conducted. As the results of these experiments, the average concentrations of PM and benzo[a]pyrene in a 35 m3 closed room were estimated to increase 1630 μg/m3 and 8.2 ng/m3, respectively, by smoking of 3 cigarettes; 1320 μ/m3 and 4.1 ng/m3, respectively, by burning of 2 incense sticks; and 2510 μg/m3 and 17.3 ng/m3, respectively, by burning of 8 cm of mosquito-repellent incense.  相似文献   

10.
Three mechanisms have been proposed to explain the carcinogenic activities of polycyclic aromatic hydrocarbons (PAHs). On the basis of the nature of the active metabolites involved, they may be termed: the diol epoxide mechanism, the quinone mechanism, and the radical-cation mechanism. In connection with studies to evaluate the relative importance of these pathways, we required practical methods for the syntheses of the active PAH metabolites involved. We now report efficient new synthesis of the o-quinones of benzo[a]pyrene (BPQ), 7,12-dimethylbenz[a]anthracene (DMBAQ), and benz[a]anthracene (BAQ). These quinones are convenient synthetic precursors of the related o-catechols, trans-dihydrodiols, and diol epoxides, as well as the stable adducts of the o-quinones with 2-deoxyadenosine and 2′-deoxyguanosine.  相似文献   

11.
Polycyclic aromatic hydrocarbons (PAHs) occur in the environment as complex mixtures including compounds with mutagenic and carcinogenic activity. The PAH profile routinely determined in environmental samples at present encompasses isomers with molecular weight (MW) not greater than 300. However, PAHs with MW >300 have been demonstrated for several matrices to contribute up to 50% of the total activity when tested for carcinogenicity in experimental animals. Recent studies indicate that among the dibenzopyrenes with MW 302 dibenzo[a,l]pyrene, possessing a fjord region, is by far the most carcinogenic PAH hitherto identified. To further elucidate the environmental relevance of this compound we have applied the isotope dilution GC/MS technique as analytical procedure to determine this compound and the related fjord region PAH naphtho[1,2-a]- and naphtho[1,2-e]pyrene in various matrices. Identification was based on comparison of UV and mass spectra as well as retention times of authentic reference materials. Determination of these PAHs was achieved after clean-up by several chromatographic steps including fractionation on a modified TABA-silica gel column. Quantitative data for matrices such as two cigarette smoke condensates, motor vehicle exhaust condensate (Otto-type engines), and tar-cork are reported. Based on toxic equivalent factors the relative contribution of dibenzo[a,l]pyrene (5.4–42.3%) to the total carcinogenic activity of a PAH profile will be discussed comprising 14 selected isomers (benzo[b]naphtho[2,1-d]thiophene; cyclopenta[cd]pyrene; benz[a]anthracene; chrysene/triphenylene; sum of benzo[b]-, benzo[k]-, and benzo[j]fluoranthene; benzo[a]pyrene; indeno[1,2,3-cd]pyrene; dibenz[a,h]anthracene; benzo[ghi]perylene; anthanthrene; dibenzo[a,l]pyrene determined in these matrices.  相似文献   

12.
The dermal route is important in occupational exposure to polycyclic aromatic compounds (PACs), but other organs may be affected. We reported that kerosene-cleaning following treatment with used engine oil increased DNA adducts in the lungs of mice viz. animals treated with used oil alone. To determine the mechanism we topically applied 3 H-BAP(100 nmol in 25 μL acetone) and washed half the mice with 25 μL kerosene 1 h after carcinogen application. Groups of four mice were sacrificed from 1 to 72 h after treatment. Lung, liver, and skin were harvested. The fraction of the radiolabel remaining in the skin of animals treated with benzo[a]pyrene (BAP) and washed with kerosene was significantly less than those not washed, beginning at 24 h (p < .05). Fractional distribution to the lungs and livers of these animals became significantly elevated. Kerosene increased transdermal water loss. Kerosene treatment compromises dermal barrier function, enhances carcinogen absorption, and alters organ distribution.  相似文献   

13.
Polycyclic Aromatic Hydrocarbons (naphtalene, acenaphtene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[j]fluoranthene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylène, indeno[1,2,3-c,d]pyrene and coronene) have been consecutively analyzed in rainwater sampled in Strasbourg (urban site) and Erstein (rural site) between January 2002 and June 2003 and between April 2002 and June 2003 on a weekly basis respectively. For the sampling of rainwater, a wet-only rainwater sampler was used together with an open collector to take the measurements of precipitation.

PAHs in rainwater were extracted by using SPE cartridges and analyzed by HPLC-fluorescence following a method developed in the laboratory.

Mean concentrations of all PAHs (Σ 16 HAPs) varied between 0.15 and 79.60 ng·L?1 in Erstein, and between 3.70 and 1596.45 ng·L?1 in Strasbourg. Naphtalene, phenanthrene, fluoranthene, pyrene, chrysene, benzo[j]fluoranthne and benzo[a]pyrene were the most concentrated PAHs analyzed. Benzo[a]pyrene was frequently detected. Seasonal effects were observed with a maximum of concentrations of PAHs during cold periods. Some spatial influences were also reported. The calculation of some PAH ratios show that diesel exhaust could be the main source of PAHs in rainwater on the two sites.  相似文献   

14.
The direct synthesis method is a relatively simple approach for generating modified oligonucleotides of defined base sequence with site-specifically placed polycyclic aromatic hydrocarbon diol epoxide-modified deoxyguanosyl and deoxyadenosyl residues. Up to 5–10 mg quantities of several different modified oligonucleotides have been synthesized for detailed NMR structural studies. Smaller amounts of modified oligonucleotides containing a single modified guanosyl residue in oligonucleotides 10–11 bases long containing up to three other unmodified guanine residues can be readily generated in smaller quantities for site-directed mutagenesis and other studies.  相似文献   

15.
Eight polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene were analyzed in sediment and benthos collected on the coast of Chiba Prefecture in Japan by gas chromatography-mass spectrometry (GC/MS). The total concentration of the PAHs ranged from 8 to 18 μ g/kg-dry in the sediments and from 36 to 59 μ g/kg-wet in the benthos, Mactra quadrangularis, Scoletoma nipponica, and Arenicola basiliensis. The PAH composition in the sediments and the benthos was similar at four sampling points and dominated by phenanthrene (Phe), fluoranthene (Flu), and pyrene (Pyr). The ratios of abundance of Flu to that of Pyr, Flu/Pyr, and of Phe/anthracene suggest that the PAHs in the benthos are derived from the combustion of fossil fuels. The ratio, R, of the PAH concentration in the benthos to that in the sediment is 2.0 for Scoletoma nipponica and 1.8 for Arenicola basiliensis in average, indicating that the bioaccumulation is not significant in the benthos. However, the R value for perylene in Scoletoma nipponica was 3.7 times as large as the average.  相似文献   

16.
The concentration of polycyclic aromatic hydrocarbons (PAHs) in sediment and excrements of annelids was measured by gas chromatography-mass spectrometry (GC/MS) and the movement of PAHs in the tidal flat was investigated. The PAH concentrations ranged 4.4–80.4 and 61.2–286.9 μg/kg-dry for the excrement of Arenicola basiliensis and of Marphysa sanguinea, respectively; the former contained about 10 times as much PAHs as the sediment and the latter about 100 times. The difference in the PAH concentration between the two organisms was attributed to their feeding behavior; M. sanguinea intakes much more detritus containing PAHs than A. basiliensis. Moreover, after the excrement of M. sanguinea had stood on the sediment for 2 hours, the PAH concentrations decreased to half. The reduction of the PAHs may arise from chemical changes owing to microorganisms and/or enzymes in the excrement of M. sanguinea.  相似文献   

17.

Polycyclic Aromatic Hydrocarbons (PAH) were determined in the leaves of Nerium oleander L. an evergreen plant that occurs widely in both urban and rural areas, to monitor the degree of pollution in the urban area of Palermo (Italy) compared to remote areas. Twenty sites (urban roadside, urban, urban park, suburban and rural) in and around Palermo city were investigated.

The purpose of this research was to investigate concentration levels and distribution patterns and relate them to possible sources. Analysis of 19 PAH was performed by gas chromatography/mass spectrometry (GCMS) using selected ion monitoring (SIM). The total amount of PAH ranged from 10 to 166 μg/Kg d.w.

Each source gives rise to a characteristic PAH pattern, and it is therefore possible to get access to the processes that generate the compounds. To this aim, the recommended as priority pollutants by the Environmental Protection Agency (EPA), perylene and three additional alkylated compounds were analyzed.

Positive correlations were found between total PAH content of the leaves with CO, benzene and particulate levels measured in air of Palermo.  相似文献   

18.

Specimens of the mussel Perna perna were collected along Moroccan coasts to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) bioaccumulated in the tissues, and to measure benzo[a]pyrene hydroxylase (BPH) activity. Chemical analysis of PAHs show that the Mediterranean (Nador, Martil, Tanger) and central Atlantic coasts (from Rabat to Jorf Lihoudi) are those most contaminated (351 245 ng.g? 1 dry weight in Tanger). The mussel contaminants were of mixed origin for most of the locations with non negligible inputs of petrogenic origin in many of them. Baseline levels of PAHs were between 6 and 55 ng.g? 1 dry weight. BPH activity showed significant correlation (r s = 0.64, P < 0.05) with total PAH concentrations at the six most contaminated stations. The baseline level of BPH activity can be identified as in the range 0.1 to 13 pmol.min? 1.mg prot? 1 along the Mediterranean and Atlantic coasts.  相似文献   

19.
Evaluation of the content of polycyclic aromatic hydrocarbons (PAHs) in agricultural soils in Poland was performed on the basis of the results of three separate investigation programmes carried out in the years 1992-1997. Two of the programmes were restricted to small regions of different exposition to anthropogenic activity, the third one covered country-wide scale. The results confirm high point contamination in areas situated in the proximity of industrial/municipal/transport pollution sources. Arable soils from rural regions were characterised by very low contamination with PAHs with median content of σ 13PAH 180 μg/kg. The usefulness of the existing European criteria for the evaluation of soil contamination with PAHs was discussed.  相似文献   

20.
To investigate metabolization of benzo[ a ]pyrene (B a P), a high-molecular-weight polycyclic aromatic hydrocarbon consisting of five aromatic rings, by a Deuteromycete Fusarium solani , a culture with [7,10- 14 C]benzo[ a ]pyrene was carried out in a batch fermentor under cometabolic conditions. In spite of drastic culture conditions with a high load of B a P (302 mg in a 1.6 liters), analysis of the growth and substrate depletion kinetics showed a classical pattern. The evolution of 14 CO 2 release demonstrated that B a P mineralization by the non-white rot fungus F. solani occurred rapidly at early stages of fermentation (15 hr) during the germination process. At the end of fermentation, 1.2% of the B a P was evolved as 14 CO 2 and 5.3% was incorporated in biomass. B a P metabolization was also confirmed by isolating metabolic products, extracted from mycelia and identified as 1,6-benzo[ a ]pyrene quinone and 3,6-benzo[ a ]pyrene quinone, by mass and ultraviolet (UV) spectroscopic analyses.  相似文献   

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