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1.

Twenty seven PAH were detected in 45 selected smoked food samples produced in Denmark, including mackerel, herring, trout, small sausages, salami, and bacon. The sum of PAH in smoked meat products ranged from 24 μg/kg for salami to 64 μg/kg in bacon, while those in fish products ranged from 22 μg/kg in smoked mackerel prepared in an electric oven to 1387 μg/kg in herring smoked by direct smoking. The concentration of benzo[a]pyrene for all sample types were below the maximum level of 5 μg/kg for smoked fish and meat set by the European Commission. Results from this survey confirm that the actual level of individual PAH in fish products is dependent on variables such as the type of wood used in the smoking process. Furthermore, the use of the benzo[a]pyrene approach for estimation of the carcinogenicity of PAH in food is confirmed. The Danish intake of benzo[a]pyrene from these smoked products is 2 to 4 ng/person/day.  相似文献   

2.
The study reports levels of parent polycyclic aromatic hydrocarbons (PAHs) in three native fish species—mullet, sea bream and tonguesole—captured from Kuwait Bay (KB) area and outside the Bay from the Auha area between October 2004 and June 2005. KB has witnessed rapid urban and industrial development since the discovery of oil and is considered to be the most productive area in the region. Whole fish analysis revealed that the lower molecular weight PAHs (pyrene, fluoranthene and phenanthrene) were present in all the three varieties of fish in considerably higher amounts. Other low molecular weight PAHs like acenaphthylene, acenaphthene and anthracene were also present but in lower concentrations. Among the higher molecular weight PAHs, the frequency of detection of benzo(a)anthracene and chrysene was high and were present in high concentrations, whereas Benzo(k)fluoranthene and benzo(a)pyrene were not frequent in detection. The contamination of Σ PAHs was higher in the winter season in mullet and sea bream but in tonguesole a reverse pattern was found. Tonguesole from KB had the highest Σ PAHs suggesting that this bottom dwelling species can be used as an indicator of sediment pollution in the area. The observed seasonality in ∑ PAHs concentration in fish coupled with species difference may be related to difference in metabolic disposition of pollutants and their habitats.  相似文献   

3.
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   

4.
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   

5.
Atmospheric sampling (gas and particles) of PAHs (naphthalene, acenaphthene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[j]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene, dibenz[a,h]anthracene, indeno[1,2,3-cd]pyrene, coronene) on XAD-2 resin (20 g) and glass fiber filters respectively, were performed in 2002 by using Digitel DA80 high-volume samplers equipped with a PM10 head. Samplings were performed in Strasbourg (east of France) and its vicinity (Schiltigheim and Erstein). Sites were chosen to be representative of urban (Strasbourg), suburban (Schiltigheim), and rural (Erstein) conditions. Field campaigns were undertaken simultaneously in urban, and suburban, urban and rural sites during spring and autumn during 4 h at a flow rate of 60 m3/h?1 which gives a total of 240 m3 · h?1 of air per sample. The period of sampling varied between 06:00 to 10:00, 11:00 to 15:00, 17:00 to 21:00 in order to evaluate a variation of concentration during automobile traffic between urban, suburban, and rural areas. Gas and particle samples were separately Soxhlet extracted for 12 h with a mixture of CH2Cl2/n-hexane (50:50 v/v), concentrated to about 1 mL with a rotary evaporator and finally dried under nitrogen. Dry extracts were dissolved in 1 mL of CH3CN before analysis. Before use, traps were Soxhlet cleaned for 24 h with the same mixture as used for the extraction. Analysis of each extract was performed by reverse phase HPLC, and fluorescence detection and quantification was done with respect to triphenylene used as internal standard. Results shows that automobile traffic seems to be the main source of PAHs in urban areas whatever the period (autumn and spring) while in autumn other sources, especially coming from combustion, influence the atmospheric contamination by PAHs.  相似文献   

6.
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   

7.
Particles present in urban air pollution are mainly derived from diesel- and gasoline-fueled vehicles. Exhaust emission is able to cause several health effects in humans including mutagenicity and carcinogenicity. Polycyclic aromatic hydrocarbons (PAHs) were measured in diesel and gasoline particulate extracts and DNA binding to CT DNA (±S9 and ±XO) was investigated. A large difference in content of 14 PAHs in diesel and gasoline extracts was observed, showing higher concentration of 14 PAHs, 6 carcinogenic PAHs, benzo[a]pyrene (B[a]P) in diesel than in gasoline extracts. Selected PAH standards of B[a]P, benzo[c]fluoranthene (B[c]F), and 3-nitrobenzanthrone (NBA) were used in 32P-postlabeling/polyacrylamide gel electrophoresis (PAGE) technique to identify CT DNA adducts formed by diesel particulate extracts. CT DNA adduct formation was higher for diesel extracts in comparison with gasoline extracts; however, no clear origin of DNA adducts derived from B[c]F-, 3-NBA-, B[a]P was detected. 32P-postlabeling/PAGE was a useful assay for analyzing and identifying PAH-DNA adducts. Occupational exposure to particulate and volatile PAH concentrations were evaluated using personal air samples and lymphocyte DNA adducts as markers of exposure. Overall air PAH concentrations were low in all eight workplaces, consisting of 97% of vapor phase compounds. DNA adducts analyzed by 32P-postlabeling assay were compared between the butanol and nuclease P1 enrichment procedures. Only in winter samples of exposed workers, butanol extraction revealed significantly higher adduct levels in comparison with those of control persons. No differences in adduct levels between exposed and control persons in summer were detected by using either butanol extraction or nuclease P1 treatment. Total concentrations of particulate and volatile PAHs measured in eight workplaces in winter showed a significant correlation with total DNA adducts analyzed in workers' lymphocytes (r = 0.852N = 8, p = .007).  相似文献   

8.
9.

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   

10.
The overcrowded large polycyclic aromatic hydrocarbon (LPAH) hexabenzo[a,cd,f,j,lm,o]perylene (HBP) was subjected to a theoretical study. The ab-initio Hartree-Fock (HF) and the density functional theory (DFT) B3LYP methods were employed to calculate energies and geometries of the stationary point conformations of HBP. The global minimum was found to be the twisted t-D 2 ; the local minimum anti-folded a-C 2h was 20.5 kJ/mol higher in energy (B3LYP/6-31G(d)). Thus, only t-D 2 -HBP exists at room temperature in solution. The enantiomerization of HBP proceeds via a pathway that connects the chiral t-D 2 to the achiral a-C 2h through a chiral twisted-folded transition state, tf-C 1 . The energy barrier for enantiomerization was 134.4 kJ/mol. The central benzene ring F of t -D 2 is highly distorted from planarity (torsion angles of 15.4° and ?30.5°), and has a remarkable resemblance to the twist angle of the central ene in the parent BAE bifluorenylidene (32°). Yet, nucleus-independent chemical shift (NICS) values, calculated at GIAO-B3LYP/6-31G(d)//B3LYP/6-31G(d) and the almost equal bond lengths (ca. 142 pm) of the central ring are indicative of the aromatic character of this ring. The NICS values are also indicative of the aromatic character of the peripheral rings and the central rings of the two minima and the transition state, consistent with the Clar picture.  相似文献   

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