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Volatile organic compounds in stormwater from a community of Beijing, China
2018
Li, Haiyan | Wang, Youshu | Liu, Fei | Tong, Linlin | Li, Kun | Yang, Hua | Zhang, Liang
Stormwater samples were collected from six different land use sites with three time-intervals during a precipitation event on August 12, 2016, from a community of Beijing, China. A total of 46 species volatile organic compounds (VOCs) were detected in these stormwater samples, including methyl tertiary-butyl ether (MTBE), aromatic hydrocarbons, halogenated aromatics, Halogenated alkanes, and alkenes. The total VOC concentrations varied in the six sites following order: highway junction > city road > gas station > park > campus > residential area, except for MTBE, which was much higher at gas station compared to other land use sites. ANOVA results indicated both land use and precipitation time intervals could significantly affect the VOC concentrations even in the small area. The Beijing atmospheric VOC concentrations were too low to explain the high concentrations in stormwater, suggesting that land surfaces may be the main sources of VOC other than the ambient atmosphere. MTBE and other VOCs correlation analysis indicated that MTBE mostly came from gasoline emissions, spills or vehicle exhausts, whereas the BTEX (benzene, toluene, ethylbenzene, Xylenes) and the halogenated aromatics were transferred from chemical plants through land surfaces accumulating and the wind blowing atmospheric VOCs. Xylenes/ethylbenzene (X/E) ratios variations indicated that stormwater incorporated larger amount of fresh emitted air during the precipitation event than prior to it. Information of these stormwater VOCs in this study could be used in the community pollution reduction strategies.
Show more [+] Less [-]Ecotoxicological risk assessment for the herbicide glyphosate to non-target aquatic species: A case study with the mussel Mytilus galloprovincialis
2018
Glyphosate (GLY) is one of the most used herbicide worldwide. Considering that information concerning the impact of GLY on bivalves is scarce, in this study we evaluated for the first time the effects of environmentally realistic concentrations of GLY (10, 100 and 1000 μg/L) to the mussel Mytilus galloprovincialis. Mussels were exposed for 7, 14 and 21 days and several biomarkers were measured in haemocytes/haemolymph (total haemocyte counts, haemocyte diameter and volume, haemolymph pH, haemolymph lactate dehydrogenase activity, haemocyte lysate lysozyme and acid phosphatase activities), as well as in gills and digestive gland (antioxidant enzyme and acetylcholinesterase activities). The concentrations of GLY and its main metabolite aminomethylphosphonic acid in the experimental tanks were also measured. The MANOVA analysis demonstrated that the experimental variables considered (exposure concentration, exposure duration, and their interaction) affected significantly biomarker responses. In addition, the two-way ANOVA analysis indicated that GLY was able to affect most of the cellular parameters measured, whereas antioxidant enzyme activities resulted to be influenced moderately. Interestingly, exposure to GLY reduced significantly acetylcholinesterase activity in gills. Although preliminary, the results of this study demonstrated that GLY can affect both cellular and biochemical parameters in mussels, highlighting a potential risk for aquatic invertebrates.
Show more [+] Less [-]Modeling and evaluating spatial variation of polycyclic aromatic hydrocarbons in urban lake surface sediments in Shanghai
2018
Yang, Jing | Yang, Yi | Chen, Rui-Shan | Meng, Xiang-Zhou | Xu, Jie | Qadeer, Abdul | Liu, Min
To explore the influence of rapid urbanization development on the accumulation of 16 priority PAHs in urban environment, thirty-three surface sediments from city lakes in different urbanized areas of Shanghai were collected to evaluate the occurrence characteristic and source apportionment of PAHs. The concentrations of Σ₁₆PAHs in lake surface sediments ranged from 55.7 to 4928 ng g⁻¹ with a mean value of 1131 ng g⁻¹ (standard deviation, 1228 ng g⁻¹), of which 4-, 5- and 6-ring PAHs were the dominant components. Spatial distribution of PAHs in lake surface sediments showed a significantly declining trend along with a decreasing urbanization gradient (one-way ANOVA, p < .05). Two hotspots of sediment PAHs were mainly distributed at highly urbanized areas with intensive population density and heavy traffic activities and at burgeoning industrial towns in the suburb. Source apportionment of total PAHs identified by a constrained positive matrix factorization model revealed that vehicle emission and combustion of coal, biomass and natural gas were the absolutely predominant sources, respectively accounting for 55.0% and 40.45% of total PAHs burden in lake sediments. Land use regression (LUR) models were successfully developed to evaluate spatial variation of PAHs contamination in urban sediments based on their significant correlations with residential land, commercial land, traffic variables, industrial sources, and population density. All PAH compounds showed strong associations with one or two source indicators (the traffic congestion index and the number of industrial sources), with the fitting R² varying from 0.529 to 0.984. Our findings suggest that energy consumption related to land use activities obviously promoted PAH accumulations in urban sediment environment during rapid development of urbanization and industrialization in Shanghai.
Show more [+] Less [-]Fatty acid composition, enzyme activities and metallothioneins in Donax trunculus (Mollusca, Bivalvia) from polluted and reference sites in the Gulf of Annaba (Algeria): Pattern of recovery during transplantation
2018
Rabei, Amina | Hichami, Aziz | Beldi, Hayet | Bellenger, Sandrine | Khan, Naim Akhtar | Soltani, Noureddine
The gulf of Annaba, the most important touristic and economic coastal zone located in Northeast Algeria, is contaminated by several pollutants from urban, agricultural, harbor and industrial activities. Elevated levels of heavy metals were detected in a locally prevalent edible mollusk Donax trunculus (Bivalvia, Donacidae) widely used as a sentinel species for the assessment of marine pollution. The present work aims to measure the difference between two localities, one being full of different pollutants (Sidi Salem) and the other being relatively clean (El Battah) and to evaluate the ability of D. trunculus to overcome the environmental stress during a transplantation experiment by a determination of fatty acid profile, the enzymes activities and the level of metallothioneins (MTs), a biomarker of metallic contamination. Adults of D. trunculus were collected at Sidi Salem (contaminated site) and transplanted into El Battah (reference site) for 21 days in cages (60 × 60 × 60 cm with a 2 mm mesh). Biochemical analyzes were conducted at different times (0, 7, 14 and 21 days). At 0-day experiment: the rate of the fatty acids, the enzymes activities and MT levels at the site of Sidi Salem (polluted site) were significantly different from those of El Battah. During the transplantation a gradual restoration of fatty acids rates, enzymes activities and MT levels was observed. At the end of the period of transplantation, the values are comparable to those of El Battah. A two-way ANOVA (time, site) on data revealed significant effects of time and site. Overally, D. trunculus is able to induce its detoxification system and to restore relatively rapidly the status of individuals from the reference site (El Battah).
Show more [+] Less [-]Heterogeneous Activation of Persulfate by Graphene Oxide-TiO2 Nanosheet for Oxidation of Diclofenac: Optimization by Central Composite Design
2018
Genç, Nevim | Durna, Elif | Gengec, Erhan
In this study, the performance of oxidation with actived persulfate (PS) by graphene oxide-TiO₂ nanosheet (GO-TiO₂) was investigated for diclofenac (DCF) removal, an anti-inflammatory analgesic being widely used in human health care and veterinary treatment. GO-TiO₂ containing oxygen functional groups is employed as an activator for the activation of PS used as the oxidizing agent. Modeling and optimization of the process were performed by central composite design (CCD) as a response surface methodology (RSM). The effects of various factors, including PS concentration, GO-TiO₂ amount, initial pH of DCF solution, and reaction time on DCF oxidation, were evaluated. When the estimated values of the full quadratic model obtained with CCD were compared with the actual experimental results, a strong agreement was obtained with an R² value of 0.9553. Besides, the model consistency was verified by analysis of variance (ANOVA) with a value of 20.17 of F value and P value of less than 0.05. After the optimization run, maximum DCF removal of 93.06% occurred with contact time of 14 min, pH of 5.54, PS concentration of 10 g/L, and 0.1 g of GO-TiO₂ as optimal variable values.
Show more [+] Less [-]Multivariate Optimization of Binary Solvent Microextraction for the Simultaneous Determination of Endocrine Disruptive Phenolic Compounds and Organochlorine Pesticides in Wastewater and Sludge Samples by GC-MS
2018
Chormey, Dotse Selali | Fırat, Merve | Bakırdere, Sezgin
This study presents the development of a sensitive and accurate dispersive liquid-liquid microextraction method using binary solvents for the simultaneous determination of endocrine disruptive compounds by GC-MS. Optimum binary solvent and dispersive solvent amounts were determined using an experimental design. The main effects of these parameters and their interaction effects were assessed using analysis of variance. The detection limits of the analytes under optimal experimental conditions ranged between 0.16–1.5 ng/mL. All analytes exhibited good linearity over broad calibration ranges, and high precision (%RSD < 8.0%) was obtained for six repeated readings of the lowest concentrations of the calibration plots. The method’s applicability and accuracy were tested on two municipal wastewater samples spiked at 10, 50, and 100 ng/mL. The recovery results obtained ranged between 82 and 108%, indicating that the method can be used to quantify the analytes in wastewater matrix with substantial accuracy. In addition, matrix matching calibration method was used to improve the percent recovery (≈ 100%) for a waste sludge sample spiked at 50 ng/mL.
Show more [+] Less [-]Water Quality in a Reservoir used for Fish Farming in Cages in Winter and Summer Periods
2018
Godoy, AntonioCesar | Corrêia, ArlindoFabrício | Boscolo, WilsonRogério | Bittencourt, Fábio | Signor, Altevir | de Oliveira, JoséD. | Feiden, Aldi
This study aimed to evaluate the vertical dynamics of the water quality, in different seasons (summer and winter), in an aquaculture area of the Iguassu River electric plant reservoir (Paraná/Brasil). Water sampling was done monthly. Samples were collected from the water column layers (epilimnion, metalimnion and hypolimnion.). Water temperature, (pH), dissolved oxygen, biochemical oxygen demand, nitrite, chlorophyll, total phosphorus, orthophosphate and ammonia were the parameters evaluated. Data from each parameter were submitted to ANOVA and to Tukey’s test at the 0.05 significance level. Correlation analysis between the variables was performed using the Spearman’s test. Multivariate approach was adopted performing Royston’s multivariate normality test. A clustering analysis was performed using Ward’s minimum variance method with a Euclidean distance matrix. This study showed that fish farming did not alter the water quality during summer and winter. Heterogeneity in summer and homogeneity in winter are observed between the layers of the water column.
Show more [+] Less [-]The Impact of Diesel Oil Pollution on the Hydrophobicity and CO2 Efflux of Forest Soils
2018
Hewelke, Edyta | Szatyłowicz, Jan | Hewelke, Piotr | Gnatowski, Tomasz | Aghalarov, Rufat
The contamination of soil with petroleum products is a major environmental problem. Petroleum products are common soil contaminants as a result of human activities, and they are causing substantial changes in the biological (particularly microbiological) processes, chemical composition, structure and physical properties of soil. The main objective of this study was to assess the impact of soil moisture on CO₂ efflux from diesel-contaminated albic podzol soils. Two contamination treatments (3000 and 9000 mg of diesel oil per kg of soil) were prepared for four horizons from two forest study sites with different initial levels of soil water repellency. CO₂ emissions were measured using a portable infrared gas analyser (LCpro+, ADC BioScientific, UK) while the soil samples were drying under laboratory conditions (from saturation to air-dry). The assessment of soil water repellency was performed using the water drop penetration time test. An analysis of variance (ANVOA) was conducted for the CO₂ efflux data. The obtained results show that CO₂ efflux from diesel-contaminated soils is higher than efflux from uncontaminated soils. The initially water-repellent soils were found to have a bigger CO₂ efflux. The non-linear relationship between soil moisture content and CO₂ efflux only existed for the upper soil horizons, while for deeper soil horizons, the efflux is practically independent of soil moisture content. The contamination of soil by diesel leads to increased soil water repellency.
Show more [+] Less [-]Response Surface Methodology for Modeling Bisphenol A Removal Using Ultrafiltration Membrane System
2018
Muhamad, MimiSuliza | Hamidon, Nuramidah | Salim, MohdRazman | Yusop, Zulkifli | Lau, WoeiJye | Hadibarata, Tony
In this work, the effects of various operating parameters (pressure, pH, BPA concentration, and filtration time) toward bisphenol A (BPA) removal via ultrafiltration (UF) membrane system were investigated using response surface methodology (RSM). Historical data design of RSM was used to obtain the interaction between variables and response as well as optimizing the process. The analysis of variance (ANOVA) showed that the third-order polynomial model was significant in which pH and filtration time were identified as significant terms that influence BPA removal. The 3D response surface plots revealed the two-factor interaction between independent and dependent variables. The optimization process of the model predicted optimum conditions of 99.61% BPA removal at 1 bar, pH 6.7, 10 μg/L BPA concentration, and 10-min filtration time. The predicted optimum conditions for BPA removal were consistent with the obtained experimental values, indicating reliable application of historical data design RSM for modeling BPA removal in UF membrane system.
Show more [+] Less [-]Amendment Type and Dose Effects onto Coexisting Copper, Lead, and Nickel Ions Distribution in Soil
2018
Šljivić-Ivanović, Marija | Smičiklas, Ivana | Jović, Mihajlo | Dimović, Slavko | Onjia, Antonije
The use of soil additives for toxic metals chemical stabilization aims to decrease in situ the pollutants’ mobility and availability. In this study, the effectiveness of rinsed red mud (RBRM) and annealed animal bones (B400) was compared in terms of Cu, Pb and Ni stabilization in two contaminated soils with contrasting properties Dystric Cambisol (CM dy) and Rendzic Leptosol (LP rz). The mobility of metals in unamended soil samples (control) and samples amended with 1% and 5% of selected additives were compared using sequential extraction protocol. The relative content of metals in readily and potentially available fractions was higher in CM dy (62% Pb, 13% Cu, and 31% Ni in exchangeable fraction) than in LP rz (< 5% of Pb, Cu, Ni in exchangeable fraction). In CM dy, both additives have caused a decrease in metal mobility with an increase of their doses. The effect of 5% sorbent addition was most pronounced related to Pb immobilization, provoking decrease of exchangeable Pb content to < 10%. Furthermore, B400 addition has redistributed investigated metals from the exchangeable to the residual phase more effectively than RBRM, and its effect on metal mobility decreased in the order Pb > Cu > Ni. Amending of LP rz soil had limited effects with no apparent decrease in exchangeable metal content. The effects of soil type variation, the type of additive and the additive dose onto metal mobility were compared according to ANOVA results. The content of readily and potentially available forms of metals was found to be (i) significantly correlated with all investigated variables for Pb, (ii) significantly correlated with soil type for Cu, and (iii) not in significant correlation with selected variables for Ni. Complex impacts of soil properties and treatment conditions on the mobility of co-contaminants emphasize the need for an individual approach to each case of contamination.
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