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1.
Tagami K  Uchida S 《Chemosphere》2006,65(11):2358-2365
Concentrations of halogens (Cl, Br and I) in 30 Japanese rivers were measured by ion chromatography and inductively coupled plasma mass spectrometry to understand their behavior in the terrestrial environment. Concentrations of Cl, Br and I in each river, obtained at 10 sampling points from the upper stream to the river mouth, tended to increase near the river mouth. The ranges of geometric means of Cl, Br and I in each river were 1.0–19.4 mg l−1, 2.5–67.9 μg l−1, and 0.18–8.34 μg l−1, respectively. To compare halogen behavior, the concentration ratios, Br/Cl and I/Cl, were calculated. The Br/Cl range was (2.3–7.8) × 10−3 (geometric mean: 3.74 × 10−3), and it was nearly constant except for the Yoneshiro river. It was estimated that 60–80% of total Br in the middle to lower parts of this river was the excess Br. The Br chemical form in all the rivers is generally considered to be Br. The I/Cl ratios had different trends in rivers flowing into the Japan Sea and Pacific Ocean, possibly due to the different geological features in the river catchments.  相似文献   

2.
The rate coefficients for the photosensitized oxidation of various phenols in aqueous solutions containing dissolved natural organic material increased in some cases with decreasing phenol concentration. For 3,4-dimethoxyphenol and 4-methoxyphenol at initial concentration going from 10 to 1.0 μM, the rate coefficients increased by a factor of 5 in a humic acid solution and by a factor of 2 in a fulvic acid solution and a lake water. For 2,4,6-trimethylphenol, 4-methylphenol and phenol at initial concentration going from 15 to 2.5 μM, they increased by a factor < 2 in the humic acid solution and were constant in the fulvic acid solution and the lake water. We suggest that the methoxy phenols, which are known to easily reduce oxidants, readily react with a class of photo-oxidants whose lifetime is expected to be > 100 μs. Thereby the long-lived photo-oxidants seem to be scavenged by the phenols themselves.  相似文献   

3.
4.
Wang X  Liu X  Wang H  Dong Q 《Chemosphere》2007,67(11):2156-2162
A species of bacteria that is capable of utilizing imazaquin as the sole carbon source was isolated from soil with repeated imazaquin applications, and was identified as Arthrobacter crystallopoietes (designated as strain “WWX-1”). This isolate degrades imazaquin as high as 200 μg ml−1, and the estimated dissipation half-lives increased from 1.51 d for the treatment at 50 μg ml−1 to 4.75 d for 200 μg ml−1. Optimal growth of WWX-1 in mineral salt medium with 50 μg ml−1 imazaquin was obtained at 35 °C and a pH of 5.0. Growth of WWX-1 was also observed in mineral salt medium with the addition of other imidazolinone herbicides such as imazethapyr and imazapyr, but not with different classes of herbicides such as metsulfuron-methyl. Two imazaquin metabolites were detected, and spectral analysis with HPLC–MS, 1H NMR, and IR revealed one metabolite with a molecular weight (MW) of 199 as quinoline-2,3-dicarboxylic anhydride. We propose that A. crystallopoietes (WWX-1) could serve as an efficient biodegradation system for remediation of water and soils that are heavily contaminated with imazaquin or other structurally similar chemicals.  相似文献   

5.
To elucidate mechanisms of Cr3+ sorption onto the unaltered solid natural organic matter, the comparative studies of this ion binding from a solution at pH 4.0 onto three selected particle size fractions: 2000–1000 μm, 630–200 μm and 63–20 μm of markedly different HS content and structure, separated by a wet sieving from an overall sample of peat (Brushwood Peat Humus) were carried out. Comparable patterns of COOH groups and CECt confirmed that for cation exchange capacity were responsible mainly cations connected with COO functional groups. It was though found that aliphatic acids in the solid state did not take part in Cr3+ binding, thus the finest studied fraction 63–20 μm of the highest contents of functional groups showed the lowest sorption capacity for Cr3+, while similar patterns of sorbed Cr3+, soluble HS content and base CEC0 indicated that these parameters were directly interrelated. The base ion exchange processes determined by CEC0 (with Ca2+ as a predominant exchangeable cation) appeared to be not the major mechanisms responsible for Cr3+ sorption. For this metal, strong binding to insoluble large molecular weight organic pool two- to threefold prevailed over the ion exchange processes. Very low acid desorption indicated generally low mobility of Cr3+-organic compounds.  相似文献   

6.
Zhu R  Sun L 《Chemosphere》2005,59(11):1583-1593
Methane fluxes were measured from three exposed tundra sites and four snowpack sites on the Fildes Peninsula in the maritime Antarctic in the summertime of 2002. The average fluxes at two normal tundra sites were −15.3 μg m−2 h−1 and −14.3 μg m−2 h−1, respectively. The fluxes from tundra site with fresh penguin dropping addition showed positive values with the average of 36.1 μg m−2 h−1, suggesting that the deposition of fresh droppings greatly enhanced CH4 emissions from the poor Antarctic tundra during penguin breeding periods. The summertime variation in CH4 flux was correlated with surface ground temperature and the precipitation. The correlation between the flux and PT0, which is the product of the precipitation and surface ground temperature, was quite strong. The diurnal cycle of CH4 flux from the tundra soils was not obtained due to local fluky weather conditions. The fluxes through four snowpack sites were also obtained by the vertical CH4 concentration gradient and their average fluxes were −46.5 μg m−2 h−1, −28.2 μg m−2 h−1, −46.4 μg m−2 h−1 and −17.9 μg m−2 h−1, respectively, indicating that tundra soils under snowpack also consume atmospheric CH4 in the maritime Antarctic; therefore these fluxes could constitute an important part of the annual CH4 budget for Antarctic tundra ecosystem.  相似文献   

7.
Profiles of PAH emission from steel and iron industries   总被引:5,自引:0,他引:5  
Yang HH  Lai SO  Hsieh LT  Hsueh HJ  Chi TW 《Chemosphere》2002,48(10):3777-1074
In order to characterize the polycyclic aromatic hydrocarbons (PAHs) emission from steel and iron industries, this study measured the stack emission of twelve steel and iron plants in southern Taiwan to construct a set of source fingerprints. The study sampled the emissions by the USEPA's sampling method 5 with the modification of Graseby for the gas and particulate phase PAH and, then, used Hewlett-Packard 5890 gas chromatograph equipped with mass spectrometer detector to analyze the samples. The steel and iron industries are classified into three categories on the basis of auxiliary energy source: Category I uses coal as fuel, Category II uses heavy oil as fuel and Category III uses electric arc furnace. The pollution source profiles are obtained by averaging the ratios of individual PAH concentrations to the total concentration of 21 PAHs and total particulate matter measured in this study. Results of the study show that low molecular weight PAHs are predominant in gas plus particulate phase for all three categories. For particulate phase PAHs, however, the contribution of large molecular weight compounds increases. Two-ring PAHs account for the majority of the mass, varying from 84% to 92% with an average of 89%. The mass fractions of 3-, 4-, 5-, 6-ring PAHs in Category I are found to be more than those of the other two categories. The mass of Category III is dominated by 7-ring PAHs. Large (or heavy) molecular weight PAHs (HMW PAHs) are carcinogenic. Over all categories, these compounds are less than 1% of the total-PAH mass on the average. The indicatory PAHs are benz[a]anthracene, benzo[k]fluoranthene, benzo[ghi]perylene for Category I, benzo[a]pyrene, acenaphthene, acenaphthylene for Category II and coronene, pyrene, benzo[b]chrycene for Category III. The indicatory PAHs among categories are very different. Thus, dividing steel and iron industry into categories by auxiliary fuel is to increase the precision of estimation by a receptor model. Average total-PAH emission factors for coal, heavy oil and electric arc furnace were 4050 μg/kg-coal, 5750 μg/l-oil, 2620 μg/kW h, respectively. Carcinogenic benzo[a]pyrene for gas plus particulate phase was 2.0 g/kg-coal, 2.4 μg/l-oil and 1.4 μg/kW h for Category I, II and III, respectively.  相似文献   

8.
Fang GC  Wu YS  Lin JB  Lin CK  Rau JY  Huang SH 《Chemosphere》2006,63(11):1912-1923
Air aerosol samples for TSP (total suspended particulate), coarse particulate (particle matter with aerodynamical diameter 2.5–10 μm, PM2.5–10), fine particulate (particle matter with aerodynamical diameter <2.5 μm, PM2.5) and metallic elements were collected during March 2004 to January 2005 at TH (Taichung Harbor) in central Taiwan. The seasonal variation average concentration of TSP (total suspended particulate), coarse particulate (particle matter with aerodynamical diameter 2.5–10 μm, PM2.5–10) and fine particulate (particle matter with aerodynamical diameter <2.5 μm, PM2.5) were in the range 132–171.1 μg m−3 and 43–49.5 μg m−3, respectively. Seasonal variation of metallic elements Cu, Mn, Zn and Fe in the TSP (total suspended particulate) shows that higher concentration was observed during spring. Seasonal variation of metallic elements Pb, Cr and Mg in the TSP (total suspended particulate) shows that higher concentration was observed during winter. The average metallic element TSP (total suspended particulate) concentration order was Fe > Zn > Mg > Cu > Cr > Mn > Pb in spring. In addition, at the TH sampling site, the average concentration variation of TSP (total suspended particulate) displayed the following order: spring > winter > autumn > summer. However, the average concentration variation of coarse particulate (particle matter with aerodynamical diameter 2.5–10 μm, PM2.5–10) displayed the following order: spring > winter > summer > autumn. Finally, the average concentration variations of fine particulate (particle matter with aerodynamical diameter <2.5 μm, PM2.5) were in the following order: winter > spring > summer > autumn at the TH sample site.  相似文献   

9.
Polycyclic aromatic hydrocarbons (PAH) were analysed in 23 soil samples (0–10 cm layer) from the Swiss soil monitoring network (NABO) together with total organic carbon (TOC) and black carbon (BC) concentration, as well as some PAH source diagnostic ratios and molecular markers. The concentrations of the sum of 16 EPA priority PAHs ranged from 50 to 619 μg/kg dw. Concentrations increased from arable, permanent and pasture grassland, forest, to urban soils and were 21–89% lower than median numbers reported in the literature for similar Swiss and European soils. NABO soils contained BC in concentrations from 0.4 to 1.8 mg/g dw, except for two sites with markedly higher levels. These numbers corresponded to 1–6% of TOC and were comparable to the limited published BC data in soil and sediments obtained with comparable analytical methods. The various PAH ratios and molecular markers pointed to a domination of pyrogenically formed PAHs in Swiss soils. In concert, the gathered data suggest the following major findings: (1) gas phase PAHs (naphthalene to fluorene) were long-range transported, cold-condensated at higher altitudes, and approaching equilibrium with soil organic matter (OM); (2) (partially) particle-bound PAHs (phenanthrene to benzo[ghi]perylene) were mostly deposited regionally in urban areas, and not equilibrated with soil OM; (3) Diesel combustion appeared to be a major emission source of PAH and BC in urban areas; and (4) wood combustion might have contributed significantly to PAH burdens in some soils of remote/alpine (forest) sites.  相似文献   

10.
Determination of triazines herbicides (atrazine and simazine) by high performance liquid chromatography (HPLC) in samples of trophic chain were worked out. Determination limits of 0.5 μg g−1 for atrazine, 0.8 μg g−1 for simazine with pesticides recovery of 70–77% in trophic chain samples were obtained. The content of simazine in soils was in range 1.72–57.89 μg g−1, in grass 5–88 μg g−1, in milk 2.32–15.29 μg g−1, in cereals 10.98–387 μg g−1, in eggs 30.14–59.48 μg g−1, for fruits: 2.45–6.19 μg g−1. The content of atrazine in soils was in range 0.69–19.59 μg g−1, in grass 7.85–23.85 μg g−1, in cereals 1.88–43.08 μg g−1. Cadmium, lead and zinc were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) in the same samples as atrazine and simazine. Determination limits for cadmium 5 × 10−3 μg g−1, for lead 1 × 10−2 μg g−1, and for zinc 0.2 × 10−3 μg g−1, were obtained. The content of cadmium in soil was in range 0.13–5.89 μg g−1, in grass 114–627.72 × 10−3 μg g−1, in milk 8.88–61.88 × 10−3 μg g−1, in cereals 0.20–0.31 μg g−1, in eggs 0.11–0.15 μg g−1, in fruits 0.23–0.59 μg g−1. The content of lead in soils was in range 0.57–151.50 μg g−1, in grass 0.16–136.57 μg g−1, in milk 1.16–3.74 μg g−1, in cereals 1.05–5.47 μg g−1, in eggs 5.79–55.87 μg g−1, in fruits 21.00–87.36 μg g−1. Zinc content in soil was in range 9.15–424.5 μg g−1, in grass 35.20–55.87 μg g−1, in milk 20.00–34.38 μg g−1, in cereals 14.94–28.78 μg g−1, in eggs 15.67–32.01 μg g−1, in fruits 14.94–18.88 μg g−1.

Described below extraction and mineralization methods for particular trophic chains allowed to determine of atrazine, simazine, cadmium, lead and zinc with good repeatability and precision. Emphasis was focused on liquid–liquid extraction and solid-phase extraction of atrazine and simazine from analysed materials, as well as, on monitoring the content of herbicides and metals in soil and along trophic chain. Higher concentration of pesticides in samples from west region of Poland in comparison to that of east region is likely related to common applying them in Western Europe in relation to East Europe. The content of metals strongly depends on samples origin (industry area, vicinity of motorways).  相似文献   


11.
Reliable predictions of the fate and behaviour of pesticides in soils is dependent on the use of accurate ‘equilibrium’ sorption constants and/or rate coefficients. However, the sensitivity of these parameters to changes in the physicochemical characteristics of soil solids and interstitial solutions remains poorly understood. Here, we investigate the effects of soil organic matter content, particle size distribution, dissolved organic matter and the presence of crop residues (wheat straw and ash) on the sorption of the herbicides atrazine and isoproturon by a clay soil. Sorption Kd's derived from batch ‘equilibrium’ studies for both atrazine and isoproturon by <2 mm clay soil were approximately 3.5 L/kg. The similarity of Koc's for isoproturon sorption by the <2 mm clay soil and <2 mm clay soil oxidised with hydrogen peroxide suggested that the sorption of this herbicide was strongly influenced by soil organic matter. By contrast, Koc's for atrazine sorption by oxidised soil were three times greater than those for <2 mm soil, indicating that the soil mineral components might have affected sorption of this herbicide. No significant differences between the sorption of either herbicide by <2 mm clay soil and (i) <250 μm clay soil, (ii) clay soil mixed with wheat straw or ash at ratios similar to those observed under field conditions, (iii) <2 mm clay soil in the presence of dissolved organic matter as opposed to organic free water, were observed.  相似文献   

12.
Subbiah D  Kala S  Mishra AK 《Chemosphere》2005,61(11):1580-1586
The fluorescence spectroscopic behavior of bromadiolone (anticoagulant rodenticide), a substituted 4-hydroxycoumarin derivative, was investigated in water and in organized media like micelles and cyclodextrins. A detailed study on various photophysical parameters like fluorescence intensity (IF), quantum yield (), lifetime (τ) and steady state fluorescence anisotropy (r) of bromadiolone in aqueous and in organized media was carried out. Bromadiolone in aqueous solution was observed to be in an aggregated state, thereby showing weak emission due to self-quenching. Marked enhancement of fluorescence intensity was observed in organized media like micelles and β-cyclodextrin. A preliminary investigation has been done to find out whether this enhancement of fluorescence can be used to develop a sensitive analytical method for determination of bromadialone in aqueous media. A linear relationship between the fluorescence intensity and concentration of bromadiolone was observed in the range of 0.15–7.9 μg ml−1 in cetyltrimethylammonium bromide (CTAB) and 0.5–26.4 μg ml−1 in β-cyclodextrin medium. The lower detection limit was found to be 37 ng ml−1 in presence of CTAB and 23 ng ml−1 in β-cyclodextrin. Comparison with 4-hydroxycoumarin, an unsubstituted analogue, was made.  相似文献   

13.
Russ AS  Vinken R  Schuphan I  Schmidt B 《Chemosphere》2005,60(11):1624-1635
Eight tertiary nonanols were synthesized via Grignard reaction and coupled by Friedel–Crafts alkylation with phenol to the corresponding nonylphenols. Six branched para-nonylphenols (NP) were obtained: 4-(3′-methyl-3′-octyl)phenol (33NP), 4-(2′-methyl-2′-octyl)phenol (22NP), 4-(2′,5′-dimethyl-2′-heptyl)phenol (252NP), 4-(2′,5′,5′-trimethyl-2′-hexyl)phenol (2552NP), 4-(2′,4′-dimethyl-2′-heptyl)phenol (242NP) and 4-(4′-ethyl-2′-methyl-2′-hexyl)phenol (4E22NP). Their structures were confirmed by GC–MS and NMR spectroscopy. These six isomers as well as the earlier synthesized 4-(3′,5′-dimethyl-3′-heptyl)phenol (353NP), 4-(3′,6′-dimethyl-3′-heptyl)phenol (363NP) and 4-(2′,6′-dimethyl-2′-heptyl)phenol (262NP) were compared with commercial NP mixtures purchased from Acros and Fluka by GC–MS (equipped with a 100 m polysiloxane column). The analyses revealed that all obtained isomers are occurring in different quantities in both commercial NP mixtures.  相似文献   

14.
PCBs and PAHs in U.K. urban air   总被引:1,自引:0,他引:1  
C. Halsall  V. Burnett  B. Davis  P. Jones  C. Pettit  K.C. Jones   《Chemosphere》1993,26(12):2185-2197
As part of a long term air monitoring programme the ambient air in four UK urban areas was sampled throughout 1991. Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were sampled from the air in London, Cardiff, Manchester and Stevenage. Both vapour and particulate phases were collected at each site, and total concentrations are reported for 26 alternate weeks of the year.

Total PAH concentrations (sum of 15 compounds) varied between 11 and 735 ng/m3 for the four sites. For each site PAH levels were dominated by the lower molecular weight compounds of phenanthrene, fluorene and pyrene, which made up more than 75% of the ΣPAH. The contribution of individual compounds to the total was broadly similar at each site in both the winter and summer. Concentrations of the higher molecular weight compounds were greater by a factor of 2.5 in the winter months.

Eight PCB congeners (28, 52, 77, 101, 118, 138, 153 and 180) were measured at each site. London gave the highest recorded value of 3.85 ng ΣPCB/m3. Values at the four sites ranged between 0.19–3.85 ng/m3, this range being similar to levels reported in other European and American cities. Congeners 28 and 52 dominated the air mixture, comprising > 80% of the measured total. PCB concentrations in the summer were, on average, double those for the winter.  相似文献   


15.
Neamtu M  Siminiceanu I  Kettrup A 《Chemosphere》2000,40(12):1407-1410
The photodegradation of five representative nitromusk compounds in water has been performed in a stirred batch photoreactor with a UV low-pressure immersed mercury lamp, at constant temperature and different doses of hydrogen peroxide. The rate constants have been calculated on the basis of experimental data and a postulated first-order kinetic model. The rate constants, at 298 K and a dose of 1.1746 μmol l−1 H2O2 ranges from 0.3567 × 10−3 s−1 for musk tibetene, to 1.785 × 10−3 s−1 for musk ambrette.  相似文献   

16.
Duman F  Obali O  Demirezen D 《Chemosphere》2006,65(11):2145-2151
In this study, submerged aquatic plant Potamogeton lucens, corresponding sediment and water samples were seasonally collected from Lake Sapanca (Turkey) and analysed for their heavy metal contents (Pb, Cr, Cu, Mn, Ni, Zn and Cd). While heavy metals concentrations in the water samples were decreased as Zn > Cr > Ni > Pb > Mn > Cu > Cd, in sediment samples were Mn > Zn > Ni > Cu > Cr > Pb > Cd, respectively. Generally, heavy metals concentrations in the plant tissues were decreased in sequence of Mn > Zn > Cu > Ni > Cr > Pb > Cd. It was determined that Cu, Mn and Zn were actively transported to the root, where they were accumulated especially in autumn. Lower accumulation factor ratios were seen in spring than other seasons. Cd exhibited a relatively clear pattern of increasing accumulation in P. lucens with increasing sediment metal concentrations. Significant positive correlations were observed between Cr, Cu, Ni and Cd contents in sediment and Cd contents in root of P. lucens. The investigations suggested that Ni and Mn have a tendency to be accumulated in leaf especially in autumn and Cr and Cd to be accumulated in shoot especially in summer.  相似文献   

17.
R. Wacker  H. Poiger  C. Schlatter 《Chemosphere》1986,15(9-12):1473-1476
14C-1,2,3,7,8-Pentachloroaibenzodioxin (P5CDD), administered to rats as single oral dose (1.69–1.75 μg/animal, 8.42–10.06 μg/kg) was eliminated with a half life of 29.5±2.7 days from the body of the animals. Residual P5CDD was located mainly in the liver and the adipose tissue. In the bile, polar metabolites of P5CDD were detected but no unmetabolized P5CDD.  相似文献   

18.
The presence of 26 congeners of polychlorinated diphenyl ethers (PCDEs) was investigated in salmon from three locations in Finland. In addition to salmon, one chlorophenol wood preservative (Ky-5) and one fly ash sample were analyzed for PCDEs. Concentrations of PCDE congeners in salmon muscle measured by high resolution gas chromatography/low resolution mass spectrometry ranged from < 0.02 to 2.4 ng/g fresh weight. The major components of tetra- to octachlorinated PCDEs in salmon were one TeCDE (22′44′-), two PeCDEs (22′44′5- and 23′44′5-) and three HxCDEs (22′44′56′-, 22′44′55′- and 22′344′5-). The Baltic salmon caught from the Simojoki River had higher levels of PCDEs than the Atlantic salmon from the Tenojoki River or salmon from Lake Saimaa in South-Finland. Same PCDE congeners which were abundant in the wood preservative were also detected in salmon, whereas PCDE congeners in the fly ash were different from those in salmon or in Ky-5.  相似文献   

19.
Tahir SS  Rauf N 《Chemosphere》2006,63(11):1842-1848
The ability of bentonite to remove malachite green from aqueous solutions has been studied for different adsorbate concentrations by varying the amount of adsorbent, temperature, pH and shaking time. Maximum adsorption of the dye, i.e. >90% has been achieved in aqueous solutions using 0.05 g of bentonite at a pH of 9. Thermodynamic parameters such as Δ, Δ and Δ were calculated from the slope and intercept of the linear plots of ln KD against 1/T. Analysis of adsorption results obtained at 298, 308, 318 and 328 K showed that the adsorption pattern on bentonite seems to follow the Langmuir, Freundlih and D–R isotherms. The temperature increase reduces adsorption capacity by bentonite, due to the enhancement of the desorption step in the mechanism. The numerical values of sorption free energy (Ea) of 1.00–1.12 kJ mol−1 indicated physical adsorption. The kinetic data indicated an intraparticle diffusion process with sorption being first order. The rate constant k was 0.526 min−1. The concentration of malachite green oxalate was measured before and after adsorption by using UV–Vis spectrophotometer.  相似文献   

20.
A field method is described, which allows the qualitative estimation of pesticide contamination in the edgeof-field runoff. The method employs cheap and easy-to-use runoff sampling bottles, which were installed in an agricultural stream catchment over a period of three growing seasons. During this time 18 runoff events were detected, in nine of which insecticide contamination was measured (maximum concentrations: lindane 0.7 μg l−1 and 12.7 μg kg−1, parathion 20 μg l−1 and 728 μg kg, fenvalerate 18.4 μg 1-1 and 924 μg kg−1). These insecticides were detected mainly as particle-bound chemicals. On about 80 % of the occasions the presence or absence of runoff measured in the field was in agreement with a simulation of runoff presence or absence using the runoff model KINEROS.  相似文献   

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