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PCB residues in the tissues of sea ducks wintering on the south coast of the Baltic Sea, Poland
2019
Tomza-Marciniak, Agnieszka | Pilarczyk, Bogumiła | Witczak, Agata | Rząd, Izabella | Pilarczyk, Renata
The Baltic Sea is known to be severely polluted by a range of chemicals, one group of which being PCBs. Although the use and production of PCBs were limited or banned in many countries in the 1970s, their presence is still observed in the environment. The aim of this study was to evaluate PCBs concentration in four species of diving sea ducks, interspecies and tissues differences, and in the case of game species, comparison of the obtained results with maximal residue levels (MRLs) and tolerable weekly intake (TWI). The level of Σi-PCBs was noted in most examined samples (liver, muscle, fat tissue) at levels ranging between < LoD and 2315.45 ng/g lw. The dominant congener was PCB 153, followed by PCB 180 and 138. The mean dl-PCB-TEQ value in the muscles of the tested tufted ducks and common pochards was 0.31 and 0.71 pg-TEQ/g lw, respectively, which is 8–25 and 18–57% of the TEQ maximum limit (ML) value for farm animal muscles. The average decrease in i-ΣPCB concentration in the fat tissue of ducks wintering in the Baltic Sea southern coast was found to be 2.9–3.3%/year. The analysis of PCB residues indicates that the common pochard and tufted duck are not suitable for consumption due to high Σi-PCB concentrations. However, the regular consumption of muscle and liver of game birds does not result in an unacceptable intake of dl-PCBs, i.e., above the TWI value.
Afficher plus [+] Moins [-]Magnetic polymer–supported adsorbent with two functional adsorption sites for phosphate removal
2019
Li, Ting | Huang, Pengwei | Liao, Taiwan | Guo, Jia | Yu, Xiang | Han, Boping | Peng, Liang | Zhu, Yi | Zhang, Yuanming
In this paper, a new magnetic polymer–supported phosphate adsorbent MPVC-EDA-Ce was prepared by loading cerium (hydr)oxides onto ethylenediamine-functionalized polyvinyl chloride for the first time. MPVC-EDA-Ce showed excellent adsorption performances towards phosphate and easy recovery. The adsorption isotherm and kinetics of MPVC-EDA-Ce followed Langmuir monolayer model and the pseudo-second-order model, respectively. The pH results demonstrated that the MPVC-EDA-Ce could effectively remove phosphate in a wide range of pH with insignificant cerium leaching. Furthermore, analyses on adsorption mechanism and effect of competing anions demonstrated the formation of strong inner-sphere complexation between cerium (hydr)oxides and phosphate, which was a selective adsorption process, while positively charged quaternary ammonium groups adsorbed phosphate via relatively weak electrostatic attraction which was a non-selective adsorption process. The study provided a good reference to design novel phosphate adsorbents with two even more functional adsorption sites and a deep insight to investigate the adsorption mechanism towards phosphate.
Afficher plus [+] Moins [-]Nano-sized Prussian blue immobilized costless agro-industrial waste for the removal of cesium-137 ions
2019
El-Din, Ahmed Mohamed Shahr | Monir, Tarek | Sayed, Moubarak A.
For human health and safety, it is of great importance to develop innovative materials with a vast capacity for powerful removal of radioactive ions from aqueous solutions. Prussian blue functionalized sugarcane bagasse (PB-SCB) was successfully prepared for the efficient elimination of radioactive cesium (¹³⁷Cs) using a nontoxic, environmentally friendly, and costless method. The prepared renewable material was characterized using different techniques to emphasize morphology, functional groups, crystal structure, and the adsorption process. The adsorption of Cs(I) was better fitted to the pseudo-second-order model than pseudo-first-order model which revealed a chemical adsorption mechanism. The experimental isotherm results were best illustrated by the Freundlich model (R² = 0.98). Besides, the obtained values for the thermodynamic parameters indicating that the adsorption process was endothermic and spontaneous in nature. In addition to demonstrating high adsorption capacity for Cs ion removal (56.7 mg/g at 30 °C), PB-SCB might consider being an efficient and cost-effective adsorbent for the decontamination of cesium, where an estimated cost analysis revealed that the expenditure for the removal of 1000 mg/L cesium from alkaline radioactive wastewater is likely to be US$0.12. Graphical abstract
Afficher plus [+] Moins [-]Landfill leachates and wastewater of maritime origin as possible sources of endocrine disruptors in municipal wastewater
2019
Wilk, Barbara K. | Fudala-Ksiazek, Sylwia | Szopińska, Małgorzata | Luczkiewicz, Aneta
In this study, wastewater from municipal services, such as a port wastewater reception facility (PRF-WW) and a municipal solid waste plant (MSWP), was tested for the presence of the suspected endocrine-disrupting compounds phthalates (PAEs) and bisphenol A (BPA). PAEs and BPA were found in this study in high concentrations in raw wastewater obtained from passenger ships (RMT-WWs) (up to 738 μg/L and 957 μg/L, respectively) collected in the Port of Gdynia and in landfill leachates (LLs) (up to 536 μg/L and up to 2202 μg/L, respectively) from a MSWP located near Gdynia. In particular, the presence of reprotoxic di(2-ethylhexyl) phthalate (DEHP, up to 536 μg/L in LLs and up to 738 μg/L in RMT-WWs) requires further action because if this compound, as well as other PAEs and BPA, is not degraded by activated sludge microorganisms, it may reach receiving waters and adversely impact aquatic organisms. Therefore, PAEs and BPA should be removed either during the onsite pretreatment of tested industrial wastewater or during tertiary treatment at municipal wastewater treatment plants (WWTPs, representing end-of-pipe technology). Graphical abstract
Afficher plus [+] Moins [-]Long-term responses of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) to the contamination of light soils with diesel oil
2019
Bęś, Agnieszka | Warmiński, Kazimierz | Adomas, Barbara
Research into trees plays a very important role in evaluations of soil contamination with diesel oil. Trees are ideal for reclaiming contaminated soils because their large biomass renders them more resistant to higher concentrations of pollutants. In the literature, there is a general scarcity of long-term studies performed on trees, in particular European beeches. The aim of this study was to evaluate the responses of Scots pines and European beeches grown for 8 years on soil contaminated with diesel oil. Selected morphological and physiological parameters of trees were analyzed. The biomass yield of Scots pines was not significantly correlated with increasing concentrations of diesel oil, but it was more than 700% higher than in European beeches. Scots pines were taller and had a larger stem diameter than European beeches during the 8-year study. The diameter of trees grown on the most contaminated soil was reduced 1.5-fold in Scots pines and more than twofold in European beeches. The length of Scots pine needles from the most contaminated treatment decreased by 50% relative to control needles. The shortest needles were heaviest. The fluctuating asymmetry (FA) of needle length was highest in Scots pines grown on the most contaminated soil, whereas the reverse was noted in the FA of needle weight. Diesel oil decreased the concentrations of chlorophylls a and b, total chlorophyll, and carotenoids. The Fv/Fm ratio of needles and leaves was influenced by the tested concentrations of diesel oil. The results of the study indicate that the Scots pine better adapts (grows more rapidly and produces higher biomass) to long-term soil contamination with diesel oil than the European beech. In European beeches, growth inhibition and leaf discoloration (a decrease in chlorophyll content) were observed already after the first year of the experiment, which indicates that 1-year-old seedlings of European beech are robust bioindicators of soil contamination with diesel oil.
Afficher plus [+] Moins [-]The interactive effect of the season and estuary position on the concentration of persistent organic pollutants in water and sediment from the Cua Dai estuary in Vietnam
2019
Nguyen, Tong Xuan | Nguyen, Binh Thanh | Tran, Huong Thu Thi | Le, Trinh Thi | Trinh, Tham Thi | Trinh, Thuy Thi | Tu, Minh Binh | Cao, Ngoc-Dan-Thanh | Vo, Hien Dieu Thi
The current study was conducted in the Cua Dai estuary, Vietnam, (1) to assess the status of persistent organic pollutants (POPs) and (2) to examine the interactive effect of season and estuary position on the concentration of the pollutants in surface water and sediment. Fifty-two water and sediment samples were taken in the dry and rainy seasons from inner- and outer-estuary positions to analyze for six POPs, including hexachlorocyclohexane isomers (HCHs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), heptachlor, aldrin, dieldrin, and polychlorinated biphenyl (PCBs). The averaged concentrations of the respective POPs in water samples were 0.07, 0.1, 0.01, 0.03, 0.001, and 0.2 μg L⁻¹ and in sediment samples were 2.6, 3.1, 0.9, 0.2, 0.2, and 121 μg kg⁻¹. Of the six POPs examined, the concentration of DDTs in sediment samples and PCBs in water samples was significantly affected by the interactive effect of the two examined factors. The concentrations of HCHs, DDTs, heptachlor, and aldrin in water samples and of HCHs in sediment samples were significantly higher in the rainy season than in the dry season. Sediment samples collected from the inner position had a significantly higher concentration of HCHs and PCBs than in the outer position. Some mechanisms possibly influenced the varying POP concentration could include (1) greater riverine discharge in the rainy season and (2) the sea dilution effect in the outer position. Therefore, the concentration of the individual examined POPs in water and sediment in the Cua Dai estuary significantly depended on either the season, estuary position, or their combination.
Afficher plus [+] Moins [-]Diel changes in aquatic biogeochemistry of a pristine stream receiving untreated urban sewage at Brazilian rainforest
2019
Santos, Debora Alves | De Paula, Francisco Carlos Fernandes
Freshwater bodies experience diel variations in aquatic chemistry, driven by natural processes. However, changes in land use, like urbanization, can modify the natural dynamics of such systems. This article describes changes in biogeochemistry of a pristine stream after receiving untreated sewage of an urban nucleus. Water samples were collected and field parameters measured, during low flow period. Temperature, pH, dissolved oxygen, electric conductivity, turbidity, total suspended solids, silicate, N-NO₃, N-NO₂, N-NH₄, dissolved and particulate organic nitrogen, PO₄, and dissolved and particulate organic phosphorus were measured hourly during a diel cycle. Upstream hydrochemistry resembles pristine watersheds in tropical rainforest, and results are restricted to a narrow range of values during the entire sampling period. Conversely, values downstream varied widely and, for some analytes, presented differences between day and night. Dissolved oxygen and electric conductivity showed the effect of the urban pulse, varying according to the routine of the population. Other field parameters did no presents a pattern that could distinguish up- and downstream stations. All the nutrients, but silicate, increased in concentration downstream. Particulate organic phosphorus, N-NO₂, and N-NH₄ were the nutrients that highlight the magnitude of the changes driven by urban effluents. These three nutrient species, and dissolved organic phosphorus, revealed a remarkably pattern that reflects the routine of the urban population, with low concentrations at night and a progressive increase starting at the early morning.
Afficher plus [+] Moins [-]A sulfur-resistant CuS-modified active coke for mercury removal from municipal solid waste incineration flue gas
2019
Liu, Wei | Zhou, Yongxian | Hua, Yinfeng | Peng, Bin | Deng, Mei | Yan, Naiqiang | Qu, Zan
Adsorption is a typical method for air pollutant removal from flue gas. A CuS-modified active coke (CuS/AC) sorbent was developed to improve the elemental mercury removal efficiency from municipal solid waste incineration (MSWI) flue gas. The influences of the loading amount of CuS, reaction temperature, and flue gas components including O₂, SO₂, H₂O, and HCl on Hg⁰ removal efficiency were investigated, respectively. The results showed that the mercury adsorption capacity of CuS/AC₍₂₀%₎ sorbent was about 7.17 mg/g with 50% breakthrough threshold, which is much higher than that of virgin active coke. The analysis of XPS indicated that HgS was the main species of mercury on spent CuS/AC, which implied that adsorption and oxidation were both included in Hg⁰ removal. S₂²⁻ played a vital role in the oxidation of physically adsorbed Hg⁰. Meanwhile, the common components of MSWI flue gas exhibited no significant inhibition effect on Hg⁰ removal by CuS/AC sorbent. CuS/AC sorbent is a promising sorbent for the mercury removal from MSWI flue gas.
Afficher plus [+] Moins [-]Activated carbon produced from waste coffee grounds for an effective removal of bisphenol-A in aqueous medium
2019
Alves, Andreia Cristina Fonseca | Antero, Romario Victor Pacheco | de Oliveira, Sergio Botelho | Ojala, Satu Anneli | Scalize, Paulo Sérgio
Bisphenol-A is widely used chemical in industry and unfortunately often detected in natural waters. Considered as an emerging pollutant, bisphenol-A represents an environmental problem due to its endocrine-disrupting behavior. The production of activated carbon from alternative precursors has shown to be attractive in the removal of emerging pollutants from the water. Activated carbon was produced from waste coffee by physical and chemical activation and applied in the removal of bisphenol-A. The samples were characterized by elemental analysis, scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and analysis of textural properties. Bisphenol-A adsorption experiments showed that the chemically activated carbon was more efficient due to its high specific surface area (1039 m²/g) compared to the physically activated carbon (4.0 m²/g). The bisphenol-A adsorption data followed the pseudo-second-order model and Langmuir isotherm, which indicated a maximum adsorption capacity of 123.22 mg/g for chemically activated carbon. The results demonstrated a potential use of the coffee grounds as a sustainable raw material for the production of chemically activated carbon that could be used in water treatment.
Afficher plus [+] Moins [-]Determination of endogenous substance change in PM2.5-induced rat plasma and lung samples by UPLC-MS/MS method to identify potential markers for lung impairment
2019
Fan, Ronghua | Ren, Qingquan | Zhou, Tao | Shang, Lei | Ma, Mingyue | Wang, Bolun | Xiao, Chunling
Exposure to fine particulate matter (PM₂.₅) could induce lung impairment aggravation. Moreover, endogenous substances are known to play a significant role in lung impairment. Therefore, the research objectives was to investigate the influence of PM₂.₅-induced lung impairment on the levels of the eight endogenous substances, γ-aminobutyric acid (GABA), acetylcholine (ACh), glutamate (Glu), serotonin (5-HT), 5-hydroxyindole-3-acetic acid (5-HIAA), noradrenaline (NE), dopamine (DA), and 3, 4-dihydroxyphenylacetic acid (DOPAC). A sensitive UPLC-MS/MS method for the simultaneous determination of these endogenous substances in rat plasma and lung tissues was developed. The validated method was successfully applied for comparing profiles of analytes in rat plasma and lung tissues. The results indicated that five endogenous substances, namely, GABA, Ach, Glu, DA, and DOPAC, had a significant change in the rats with PM₂.₅-induced lung impairment.
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