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1.
Hexavalent chromium [Cr(VI)] and arsenite [As(III)] are the most toxic forms of chromium and arsenic respectively, and reduction of Cr(VI) to Cr(III) and oxidation of As(III) to As(V) has great environmental implications as they affect toxicity and mobility of these toxic species. Bacillus firmus strain TE7, resistant to chromium and arsenic was isolated from tannery effluent. The strain exhibited ability to reduce Cr(VI) and oxidize As(III). It reduced 100 mg L?1 Cr(VI) within 60 h in nutrient broth and oxidized 150 mg L?1 As(III) within 10 h in minimal medium. It also completely reduced 15 mg L?1 Cr(VI) and oxidized 50 mg L?1 of As(III) simultaneously in minimal medium. To the best of our knowledge, this is the first bacterial strain showing simultaneous reduction of Cr(VI) and oxidation of As(III) and is a potential candidate for bioremediation of environments contaminated with these toxic metal species.  相似文献   

2.
Venlafaxine hydrochloride is a structurally novel antidepressant. Its occurrence in surface waters and drinking water has only been reported in recent works. The aim of this work is to assess the acute and chronic sublethal toxicity of venlafaxine in relevant taxa of riparian ecosystems. We used the fern Polystichum setiferum during the critical life stage of development. Reliable biomarkers of cell viability (mitochondrial activity), plant physiology (chlorophyll), and growth (DNA content) were assessed as sensitive endpoints of toxicity. About DNA quantification, our results show that venlafaxine induces acute lethal phytotoxicity at 24 and 48 h (LOECs 1 μg L?1 and 0.1 μg L?1, respectively). At 24 h, hormetic effects in spores of P. setiferum mitochondrial activity mask lethality and adverse effects are observed (LOEC 1 μg L?1). At 48 h a reduction in the mitochondrial activity happens (LOEC 10 μg L?1). In chronic exposure of 1 week, LOEC for DNA is 0.1 μg L?1. Mitochondrial activity showed a strong hormetic stimulation of a surviving spore population (LOEC 10 μg L?1). Changes were not observed in chlorophyll autofluorescence. Environmental concentrations of venlafaxine can be deleterious for the development of significant populations of sensitive individuals in riparian ecosystems.  相似文献   

3.
Antibiotics and antibacterials are present in water bodies worldwide but little is known about their effects on the biological processes often used to treat water. In this research, the effect of antibiotics on bacterial activity and community structure was investigated by growing biofilms in the presence and absence of a mixture of three compounds (sulfamethoxazole, erythromycin, and ciprofloxacin) in a continuous-flow rotating annular bioreactor fed acetate as a carbon and energy source. Steady-state, surface area-normalized substrate utilization rates for all antibiotic treatments (all at 0.33 μg L?1, all at 3.33 μg L?1, and 1 at 3.33 μg L?1 with the other 2 at 0.33 μg L?1) were similar to the control experiments. Higher attached biomass levels in the experiments with ciprofloxacin at 3.33 μg L?1 resulted in lower steady-state biomass-normalized substrate utilization rates in comparison to other runs. Microbial community analyses via automated ribosomal intergenic spacer analysis revealed significant shifts in community structure for the experiments dosed with the highest concentrations of ciprofloxacin, suggesting that the antibiotic selected for more resistant bacterial strains. The results of this research also suggest that mixtures of antibiotics at the sub-μg L?1 concentrations typically observed in surface waters are unlikely to affect biological process performance, at least in terms of the degradation of easily assimilable compounds. Conversely, changes to community structure and biofilm quantity might be expected with ciprofloxacin at μg L?1 concentrations.  相似文献   

4.
Pyrethroid insecticides are extensively and increasingly applied in agricultural and residential environments in China. Children’s exposure to pesticides attracted global concerns because of their particular vulnerability. Several studies have reported residual pyrethroid levels in urine both in adults and in children. However, few published data focused on very young infants. The study aimed to assess exposure to pyrethroid insecticides in young infants and investigate the potential influence factors on pyrethroid exposure levels. Data on pyrethroids exposure was based on questionnaire items and measurement of urinary metabolite levels among 481 infants. We detected pyrethroid metabolites of 3-phenoxybenzoic acid (3-PBA), cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (cis-DCCA and trans-DCCA) in urine using a gas chromatography-mass spectrometry method. Median values for urinary pyrethroid metabolites in these infants were 0.39 μg L?1 for 3-PBA, 0.18 μg L?1 for cis-DCCA, 0.92 μg L?1 for trans-DCCA, respectively. About 60.9% of the infants had urinary concentrations of three pyrethroid metabolites that were above the level of 0.10 μg L?1 (limit of detection, LOD). These findings of the urinary metabolites were comparable or slightly higher than those children from the other countries. From questionnaire, we learned that more than 70% of households reported that they or family members had applied mosquito repellents in infants. Above data indicated the need to assess the potential adverse effects of pyrethroids exposure on infants in order to take adequate measures to protect them from pesticide exposures during early childhood.  相似文献   

5.
Uptake, accumulation and translocation of caffeine by Scirpus validus grown in hydroponic condition were investigated. The plants were cultivated in Hoagland’s nutrient solution spiked with caffeine at concentrations of 0.5–2.0 mg L?1. The effect of photodegradation on caffeine elimination was determined in dark controls and proved to be negligible. Removal of caffeine in mesocosms without plants showed however that biodegradation could account for about 15–19% of the caffeine lost from solutions after 3 and 7 d. Plant uptake played a significant role in caffeine elimination. Caffeine was detected in both roots and shoots of S. validus. Root concentrations of caffeine were 0.1–6.1 μg g?1, while the concentrations for shoots were 6.4–13.7 μg g?1. A significant (p < 0.05) positive correlation between the concentration in the root and the initial concentrations in the nutrient solution was observed. The bioaccumulation factors (BAFs) of caffeine for roots ranged from 0.2 to 3.1, while BAFs for shoots ranged from 3.2 to 16.9. Translocation from roots to shoots was the major pathway of shoot accumulation. The fraction of caffeine in the roots as a percentage of the total caffeine mass in solution was limited to 0.2–4.4% throughout the whole experiment, while shoot uptake percentage ranged from 12% to 25% for caffeine at the initial concentration of 2.0 mg L?1 to 50–62% for caffeine at the initial concentration of 0.5 mg L?1. However, a marked decrease in the concentration of caffeine in the shoots between d-14 and d-21 suggests that caffeine may have been catabolized in the plant tissues subsequent to plant uptake and translocation.  相似文献   

6.
Reactive black B (RBB) is a group of azo dyes that are widely used in the textile industry. In this study, a new microbial strain was isolated from azo dye contaminated river sediment which is capable of degrading RBB. The strain was identified as Bacillus cereus strain HJ-1 by 16S rRNA gene sequences analysis. The optimal conditions for RBB decolorization by B. cereus strain HJ-1 are: 25 °C, pH 8, 1 CMC of triton X-100, 0.15 g L?1 of added yeast extract, 0.125 g L?1 of added glucose and static culture. Then the toxicity of RBB on the green algae Chlorella vulgaris was determined. The results showed that the median effective concentration (EC50) of RBB for C. vulgaris is 48 mg L?1 and toxicity will really decrease after decolorization. In the end, B. cereus strain HJ-1 was amended into the origin river sediment and analyzed the whole microbial community structure of river sediment samples by PCR-DGGE technique. The result showed that B. cereus strain HJ-1 could survive in the river sediment after 12 d of incubation. Based on this work, we hope that these findings could provide some useful information for applying the decolorization of RBB in our environment.  相似文献   

7.
Aerosol from the burning two types of sandalwood-based incense, Hsing Shan and Lao Shan, was analyzed to characterize the chemical profile of total particulate matter emitted. The total particulate matter (PM) mass emission factors were 46.3 ± 2.68 mg g?1 of Hsing Shan incense and 43.7 ± 1.08 mg g?1 of Lao Shan incense. Chemical analysis of emissions from the two types of incense revealed that of the 25 components in four groups characterized, anhydrosugars formed the major group, at 46.7–52.2% w/w of the identified particulate and 1078.3–1169.8 μg g?1 of incense, followed by inorganic salts at 30.4–31.8% w/w of identified particulate and 681.6–734.0 μg g?1 of incense, carboxylic acids at 12.0–17.1% w/w of the identified particulate and 268.6–392.8 μg g?1 of incense, and sugar alcohols at 4.44–5.38% w/w of the identified particulate and 102.3–120.6 μg g?1 of incense. More anhydrosugars and sugar alcohols were emitted from Lao Shan incense than from Hsing Shan incense whereas more carboxylic acids and organic salts were emitted from Hsing Shan than from Lao Shan. These differences were due to structural and functional differences in the young sandalwood used to make Hsing Shan and the aged sandalwood used to make Lao Shan. The anhydrosugar levoglucosan, used as a marker of biomass burning, was always the most abundant species in emitted PM for both incenses (Lao Shan 21.7 mg g?1 of PM and Hsing Shan 18.7 mg g?1). K+ and Cl? were the second most abundant components (K+ and Cl? were summed), accounting for 10.6 mg g?1 of Hsing Shan PM and 9.85 mg g?1 of Lao Shan PM. The most abundant carboxylic acids in the emissions were formic, acetic, succinic, glutaric and phthalic acid. The latter is a fragrance ingredient and a potential health hazard and was twice as prevalent in Lao Shan emissions. Xylitol was the most prevalent of the sugar alcohols at 35.7–36.6% w/w of total identified sugar alcohols. These abundant species are potential markers for incense burning. K+, levoglucosan, mannosan and xylitol are already reported in discriminator ratios for wood burning and it is proposed here that these can and should also apply to incense burning. The calculated discriminator ratios for two types of incense burning reported here are 0.229–0.288 for K/Levo, 12.5–13.5 for Levo/Manno, and 21.5–23.7 for the novel discriminator ratio Levo/Xylitol.  相似文献   

8.
Environmental heavy metal contamination is a case of concern for both animal and human health. Studying the fate of metals in plant or animal tissues may provide information on pollution. In the present study, we investigated the possibility to follow the biological fate of chromium and platinum uptake in common garden snails (Helix aspersa), typically accumulating high concentrations of metals from their environment. Chromium and platinum were administered orally to snails in 5 groups (n = 25/group): control, food contaminated by ca. 2.5 μg g?1 and 19 μg g?1 chromium and 2.5 μg g?1 and 25 μg g?1 platinum, for 8 weeks. Following exposure, surviving snails were sacrificed, shell and remaining tissue investigated by ICP-MS, and shell, midgut gland and mantle by nano-secondary ion mass-spectrometry (Nano-SIMS). 12C14N-normalized platinum and 40Ca-normalized chromium measurements indicated highest enrichments in cellular vesicles of the midgut gland, and lower concentrations in mantle and shell, with significantly higher platinum and chromium concentrations in the 2 exposure groups vs. control (P < 0.05), with somewhat differing distribution patterns for chromium and platinum. Comparable results were obtained by ICP-MS, with both chromium and platinum fed snails showing drastically elevated concentrations of metals in shell (up to 78 and 122 μg g?1 dw platinum and chromium, respectively) and in other tissues (up to 200 and 1125 μg g?1 dw platinum and chromium, respectively). Nano-SIMS allowed for semi-quantitative comparison of metal fate in snail tissues, making this an interesting technique for future studies in the area of environmental pollution.  相似文献   

9.
Perfluoroalkyl acids (PFAs), one kind of emerging contaminants, have attracted great attentions in recent years. However, the study about their bioaccumulation mechanism remains scarce. In this research, the bioaccumulation of six kinds of PFAs in water flea Daphnia magna was studied. The uptake rates of PFAs in D. magna ranged from 178 to 1338 L kg?1 d?1, and they increased with increasing perfluoroalkyl chain length; the elimination rates ranged from 0.98 to 2.82 d?1. The bioaccumulation factors (BAFs) of PFAs ranged from 91 to 380 L kg?1 in wet weight after 25 d exposure; they increased with increasing perfluoroalkyl chain length and had a significant positive correlation with the n-octanol/water partition coefficients (log Kow) of PFAs (p < 0.05). This indicated that the hydrophobicity of PFAs plays an important role in their bioaccumulation. The BAFs almost kept constant when the PFA concentrations in aqueous phase increased from 1 to 10 μg L?1. Scenedesmus subspicatus, as the food of D. magna, did not significantly affect the bioaccumulation of PFAs by D. magna. Furthermore, the body burden of PFAs in the dead D. magna was 1.08–2.52 times higher than that in the living ones, inferring that the body surface sorption is a main uptake route of PFAs in D. magna. This study suggested that the bioaccumulation of PFAs in D. magna is mainly controlled by their partition between organisms and water; further research should be conducted to study the intrinsic mechanisms, especially the roles of protein and lipid in organisms.  相似文献   

10.
The concentrations of polychlorinated biphenyls (PCBs) were assessed at four sites in Khour-e-Mousa (Mah-Shahr), Iran. Sea water, sediment and fish (cynoglossus bilineatus) samples were taken at each site and were analysed for PCB levels. To investigate the possible source of PCBs found in fish samples, sediments and waters were collected from four sites (D1, D2, D3, and D4) and studied. The relationship between PCB concentrations in sediment, water and fish is discussed. The results indicate that PCBs are detected in all fish samples and its concentration range from 3.2 to 102.7 μg kg?1 dry weight and 5.4–149.7 μg kg?1 dry weight in cold and warm seasons, respectively. The D2 and D4 sites were found to have the highest and lowest levels of PCB concentrations, respectively. Total congener PCB (CB, 28, 52, 44, 101, 149, 118, 153, 138, and 180) concentrations at the sediment samples for D1, D2, D3, and D4 sites ranged from 1.6 to 30.9 μg kg?1 dry weight and 2.3–47.1 μg kg?1 dry weight in cold and warm seasons, respectively. The total PCB concentrations for D2 site were found to be significantly higher than other three sites. Total water congener PCB (CB, 28, 52, 44, 101, 149, 118, 153, 138, and 180) concentrations ranged from 0.01 to 0.25 μg L?1 and 0.02–0.39 μg L?1 in cold and warm seasons, respectively.  相似文献   

11.
The object of this study was to develop an accurate estimation method to evaluate the contribution of the various compartments of swine husbandry to dust and GHG (greenhouse gases, CO2, CH4 and N2O) emission into the atmosphere during one year of observation.A weaning, a gestation, a farrowing and a fattening room in an intensive pig house were observed in three different periods (Autumn–Winter, Springtime and Summer, monitoring at least 60% of each period (20% at the beginning, in the middle and at the end) of each cycle).During monitoring, live weight, average live weight gain, number of animals and its variation, type of feed and feeding time were taken into account to evaluate their influence on PM10, or the fraction of suspended particulate matter with an aerodynamic diameter less than or equal to 10 μm [Emission Inventory Guidebook, 2007. B1100 Particle Emissions from Animal Husbandry Activities. Available from: <http://reports.eea.europa.eu/EMEPCORINAIR5/en/B1100vs1.pdf> (accessed October 2008)] and to define GHG emission.The selected piggery had a ventilation control system using a free running impeller to monitor continuously real-time environmental and management parameters with an accuracy of 5%.PM10 concentration was monitored by a sampler (Haz Dust EPAM 5000), either continuously or through traditional gravimetric technique, and the mean value of dust amount collected on the membranes was utilized as a correction factor to be applied to continuously collected data.PM10 concentration amount incoming from inlets was removed from PM10 emission calculation, to estimate the real contribution of pig house dust pollution into atmosphere.Mean yearly emission factor of PM10 was measured in 2 g d?1 LU?1 for the weaning room, 0.09 g d?1 LU?1 for the farrowing room, 2.59 g d?1 LU?1 for the fattening room and 1.23 g d?1 LU?1 for the gestation room. The highest PM10 concentration and emission per LU was recorded in the fattening compartment while the lowest value was recorded in the farrowing room.CO2, CH4 and N2O concentrations were continuously measured in the exhaust ducts using an infrared photoacoustic detector IPD (Brüel & Kjaer, Multi-gas Monitor Type 1302, Multipoint Sampler and Doser Type 1303) sampling data every 15 min, for the 60% of the cycles.Yearly emission factor for CO2 was measured in 5997 g d?1 LU?1 for the weaning room, 1278 g d?1 LU?1 for the farrowing room, 13,636 g d?1 LU?1 for the fattening room and 8851 g d?1 LU?1 for the gestation room.Yearly emission factor for CH4 was measured in 24.57 g d?1 LU?1 for the weaning room, 4.68 g d?1 LU?1 for the farrowing room, 189.82 g d?1 LU?1 for the fattening room and 132.12 g d?1 LU?1 for the gestation room.Yearly emission factor for N2O was measured in 3.62 g d?1 LU?1 for the weaning room, 0.66 g d?1 LU?1 for the farrowing room, 3.26 g d?1 LU?1 for the fattening room and 2.72 g d?1 LU?1 for the gestation room.  相似文献   

12.
Air–water exchange fluxes of polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in air and water samples from two sites on the Kenting coast, located at the southern tip of Taiwan, from January to December 2010. There was no significant difference in the total PAH (t-PAH) concentrations in both gas and dissolved phases between these two sites due to the less local input which also coincided to the low levels of t-PAH concentration; the gas and dissolved phases averaged 1.29 ± 0.59 ng m?3 and 2.17 ± 1.19 ng L?1 respectively. The direction and magnitude of the daily flux of PAHs were significantly influenced by wind speed and dissolved PAH concentrations. Individual PAH flux ranged from 627 ng m?2 d?1 volatilization of phenanthrene during the rainy season with storm–water discharges raising dissolved phase concentration, to 67 ng m?2 d?1 absorption of fluoranthene during high wind speed periods. Due to PAH annual fluxes through air–water exchange, Kenting seawater is a source of low molecular weight PAHs and a reservoir of high molecular weight PAHs. Estimated annual volatilization fluxes ranged from 7.3 μg m?2 yr?1 for pyrene to 50 μg m?2 yr?1 for phenanthrene and the absorption fluxes ranged from ?2.6 μg m?2 yr?1 for chrysene to ?3.5 μg m?2 yr?1 for fluoranthene.  相似文献   

13.
We here report complementary trace element (Fe, Pb, Cd, Zn, Cr, Cu, Ni and sulfur) concentrations and ratios in pine needles collected in the urban area of Cologne, Germany. Potential element sources are discussed in conjunction with enviromagnetic and PAH data to evaluate air quality. Foliar trace element concentrations of Zn, Cr, Cu, Ni and sulfur are close to essential nutrient levels. Median concentrations of foliar Fe, Pb and Cd in Cologne are 132, 1.1, and 0.06 μg g?1, respectively. Thus these elements are enhanced over biogenic background levels and show significant accumulation with needle exposure time. Foliar sulfur concentrations vary between 868 and 2076 μg g?1 with a median value of 1409 μg g?1, except for two locations where 2370 and 2379 μg g?1 were observed. Cadmium serves as an indicator for local industrial emissions with short transport distances of only a few kilometres in Cologne City. Elevated Fe, Pb and Zn concentrations mark areas with higher traffic loads and agree with enhanced PAH burdens and magnetic susceptibility intensities of pine needles. Isopleths mapping and source differentiation of atmospheric pollutants using foliar trace elements is feasible. For temporal or spatial high-resolution studies more cost-effective environmental magnetics is recommended, which may guide in design of detailed studies aiming at identification and allocation of emission sources. Hereby, a combination of organic tracers (PAH), magnetic properties, and trace metals is considered most reliable.  相似文献   

14.
White-nose syndrome (WNS) is a condition associated with white fungal growth on ears, wings, and nose of hibernating bats; this condition has recently resulted in high bat mortality in the northeastern United States. Nevertheless, the pathogenesis of morbidity and mortality are still unknown. Elevated exposure to toxic contaminants could be a contributing factor via the consequent immunosuppression and endocrine disruption. In this study, diseased little brown bats (Myotis lucifugus) were collected from several hibernacula in eastern New York State in 2008. Fat tissues of bats were analyzed for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), and organochlorine pesticides (OCPs; DDT, chlordanes, HCB, and HCH), and liver was analyzed for perfluorinated compounds (PFCs). A reference population of little brown bats, not affected by WNS, was also collected from a cave in Kentucky for the analysis of trace organic contaminants. Concentration of PCBs in fat tissues of bats from New York ranged from 1900 ng g?1 to 35 000 ng g?1, lipid wt, with the highest concentrations found in bats collected from caves in Albany County. High concentrations of PCBs were also found in bats from Kentucky (17 100–18 400 ng g?1, lipid wt). Total PBDE concentrations in fat tissues ranged from 520 ng g?1 to 10 900 ng g?1, lipid wt, in bats from New York and from 4300 ng g?1 to 13 000 ng g?1, lipid wt, in bats from Kentucky. High concentrations of DDT (26 900 ng g?1, lipid wt), chlordanes (6350 ng g?1, lipid wt), and HCB (260 ng g?1, lipid wt) were found in bats from New York. Concentrations of hexabromobiphenyl congener 153 (PBB 153) in bats from New York ranged from 8.6 ng g?1 to 12 4000 ng g?1, lipid wt. Concentrations of PFCs were on the order of a few tens to a few hundreds of nanograms per gram liver, on a wet weight basis. Overall, high concentrations of PCBs, PBDEs, DDT, and chlordanes were found in fat tissues of diseased bats from New York, although the concentrations in bats from non-diseased, reference population, from Kentucky were also high.  相似文献   

15.
In this work, the photocatalytic degradation of aqueous microcystin-LR was studied using TiO2 and ZnO as photocatalysts. The process was optimised and characterised at the bench scale (200 mL); both semiconductors exhibited a high degradation capacity at reaction times of 1 min (degradation greater than 95%). The transient species that were observed indicate that the degradation occurs via the multiple hydroxylation and elimination of the labile peptide residues of the molecule. When photocatalysis was applied in a continuous treatment system (20–50 L), the photocatalytic process exhibited a high degradation efficiency, which resulted in residual microcystin-LR concentrations that were less than 1 μg L?1 (C0 = 5 μg L?1).  相似文献   

16.
Seawater, atmospheric dimethylsulfide (DMS) and aerosol compounds, potentially linked with DMS oxidation, such as methanesulfonic acid (MSA) and non-sea-salt sulfate (nss-SO42?) were determined in the North Yellow Sea, China during July–August, 2006. The concentrations of seawater and atmospheric DMS ranged from 2.01 to 11.79 nmol l?1 and from 1.68 to 8.26 nmol m?3, with average values of 6.20 nmol l?1 and 5.01 nmol m?3, respectively. Owing to the appreciable concentration gradient, DMS accumulated in the surface water was transferred into the atmosphere, leading to a net sea-to-air flux of 6.87 μmol m?2 d?1 during summer. In the surface seawater, high DMS values corresponded well with the concurrent increases in chlorophyll a levels and a significant correlation was observed between integrated DMS and chlorophyll a concentrations. In addition, the concentrations of MSA and nss-SO42? measured in the aerosol samples ranged from 0.012 to 0.079 μg m?3 and from 3.82 to 11.72 μg m?3, with average values of 0.039 and 7.40 μg m?3, respectively. Based on the observed MSA, nss-SO42? and their ratio, the relative biogenic sulfur contribution was estimated to range from 1.2% to 11.5%, implying the major contribution of anthropogenic source to sulfur budget in the study area.  相似文献   

17.
18.
The liquid chromatography–electrospray ionization-tandem mass spectrometer (LC–MS/MS) method coupled with an automated solid-phase extraction procedure has been developed to identify 22 psychiatric pharmaceuticals, including seven anxiolytic-sedative-hypnotics, six antidepressants, and nine anti-schizophrenia drugs, in wastewater samples from two psychiatric hospital wastewater treatment plants (P-WWTPs) and three municipal wastewater treatment plants (M-WWTPs) in Beijing, China. Analyte recoveries from spiking experiments in the WWTP influent and effluent at three concentrations ranged from 70% to 110%, excluding sulpiride, ziprasidone, and olanzapine. Method detection limits for five, eight, and nine analytes in the WWTP influent and effluent were 20–80, 1–16, and <1 ng L?1, respectively. High psychiatric pharmaceutical concentrations (e.g., ~942 ng L?1oxazepam, 5552–12,782 ng L?1 clozapine, 2762–9832 ng L?1sulpiride, and 2030–4967 ng L?1quetiapine) were frequently observed in P-WWTP influent compared to M-WWTPs. Although P-WWTPs typically had higher removal rates, significantly higher concentrations of the target compounds were observed in the P-WWTP secondary effluent than in the M-WWTP influent (e.g., ~752 ng L?1oxazepam, ~8183 ng L?1 clozapine, ~10,833 ng L?1sulpiride, and ~1168 ng L?1quetiapine). Thus, the discharge control of psychiatric pharmaceuticals from psychiatric hospitals requires improvement.  相似文献   

19.
Henry’s law constants H of formaldehyde and benzaldehyde were determined using a dynamic system based on the water/air equilibrium at the interface within the length of a microporous tube. The measurements were conducted over the range 273–293 K in (i) deionized water, (ii) 35 g L?1 solution of NaCl simulating seawater and (iii) two nitric acid solutions, i.e. 0.63 and 6.3 wt%.In pure water, the obtained data were used to derive the following Arrhenius expressions: ln H = (6423 ± 542)/T ? (13.4 ± 2.0) and ln H = (6258 ± 280)/T ? (17.5 ± 1.0) for formaldehyde and benzaldehyde, respectively. The H values, calculated at 293 K from Arrhenius expressions cited above were the following (in units of M atm?1): H = 5020 ± 1170 (formaldehyde), H = 47 ± 5 (benzaldehyde). The temperature dependence of H permits then to derive the solvation enthalpies for both compounds: ΔHsolv = ?(53.4 ± 4.5) kJ mol?1 and ΔHsolv = ?(52.0 ± 2.3) kJ mol?1 for formaldehyde and benzaldehyde, respectively.In 35 g L?1 salt solution, the H values were 27–66% and 12–21% lower than their respective determinations in deionized water, for formaldehyde and benzaldehyde respectively. The observed salt effect was used to estimate the following Setschenow coefficients at 293 K for 0.6 M NaCl: formaldehyde (0.21) and benzaldehyde (0.09).In 6.3 wt% nitric acid solution, H values of benzaldehyde were approximately 30% higher than those found in pure water although no significant influence was observed for formaldehyde.Finally, our experimental data were then used to estimate the fractions of formaldehyde and benzaldehyde in atmospheric aqueous phase and their derived atmospheric lifetimes.  相似文献   

20.
Polybrominated diphenyl ether (PBDE) concentrations in sediment and fish from 12 principal rivers in Taiwan were investigated to determine their association with water quality parameters as well as the biota-sediment accumulation factor (BSAF) in fish with different living patterns. The highest PBDE concentration in sediment was found in the Bajhang River (261 ng g?1 dry weight (d.w.)) and the lowest in the Beinan River and the Da-an River (0.17 ng g?1 d.w.). The PBDE concentrations in fish samples ranged from 1.28 ng g?1 d.w. (Oreochromis niloticus niloticus) in the Yanshuei River to 33.7 ng g?1 d.w. (Varico rhinos barbatulus) in the Da-an River. We conclude that PBDEs contamination in sediment was significantly affected by NH3–N, pH, and DO. The BSAF results showed a parabolic trend from low- to high-brominated BDEs. Fish easily accumulated the congeners BDE-47, -100, -119, -126, and -154 from sediment. The BSAF decreased in the following order: PeBDE > HxBDE > TeBDE > other BDEs. Principle component analysis showed that demersal fish have different PBDE sources than do pelagic fish. We conclude that living and feeding habits are critical factors affecting PBDE accumulation in fish.  相似文献   

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