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Water Quality Assessment and Variation Trends Analysis of the Min River Sea-Entry Section, China Full text
2019
Rao, Qinghua | Qiu, Yu | Li, Jiabing
In order to further understand the status of the water quality of Min River’s sea-entry section, the index systems for water environmental quality assessment was built based on twenty evaluation parameters including dissolved oxygen (DO), permanganate index (CODMₙ), chemical oxygen demand (CODCᵣ), biochemical oxygen demand (BOD₅), ammonia (NH₃-N), total phosphorus (TP), and total nitrogen (TN). Water environmental quality of Min River’s sea-entry section in 2015–2017 was evaluated by utilizing the entire-array-polygon synthesis illustration method, accompanied by the time-dependent trend analysis. The results demonstrated that the water environmental quality of Min River’s sea-entry section was between the levels I and II of the Environmental Quality Standards for Surface Water (EQSSW, GB3838-2002) in 2015–2017, indicating a generally good water quality. The water quality was affected by both natural factors (such as temperature, rainfall, and runoff) and human factors and had a tendency to deteriorate at the duration of 2015–2017. The research results are of great significance for further understanding of the discharge of pollutants from the Min River basin and will be a strong support for the scientific decision-making of marine management in Fujian Province.
Show more [+] Less [-]Ambient air pollution and risk of type 2 diabetes in the Chinese Full text
2019
Li, Hui | Duan, Donghui | Xu, Jiaying | Feng, Xiaoqi | Astell-Burt, Thomas | He, Tianfeng | Xu, Guodong | Zhao, Jinshun | Zhang, Lina | You, Dingyun | Han, Liyuan
We performed a time series analysis to investigate the potential association between exposure to ambient air pollution and type 2 diabetes (T2D) incidence in the Chinese population. Monthly time series data between 2008 and 2015 on ambient air pollutants and incident T2D (N = 25,130) were obtained from the Environment Monitoring Center of Ningbo and the Chronic Disease Surveillance System of Ningbo. Relative risks (RRs) and 95% confidence intervals (95% CIs) of incident T2D per 10 μg/m³ increases in ambient air pollutants were estimated from Poisson generalized additive models. Exposure to particulate matter < 10 μm (PM₁₀) and sulfur dioxide (SO₂) was associated with increased T2D incidence. The relative risks (RRs) of each increment in 10 μg/m³ of PM₁₀ and SO₂ were 1.62 (95% CI, 1.16–2.28) and 1.63 (95% CI, 1.12–2.38) for overall participants, whereas for ozone (O₃) exposure, the RRs were 0.78 (95% CI, 0.68–0.90) for overall participants, 0.78 (95% CI, 0.69–0.90) for males, and 0.78 (95% CI, 0.67–0.91) for females, respectively. Exposure to PM₁₀ and SO₂ is positively associated with T2D incidence, whereas O₃ is negatively associated with T2D incidence.
Show more [+] Less [-]Application of modified receptor model for soil heavy metal sources apportionment: a case study of an industrial city, China Full text
2019
Li, Yufeng | Zhao, Zhongqiu | Yuan, Ye | Zhu, Peitian | Li, Xuezhen | Guo, Anning | Yang, Qiao
As we all know, geochemical data usually contain outliers and they are heterogeneous, which will severely affect the use of receptor models based on classical estimates. In this paper, an advanced modified RAPCS-RGWR (robust absolute principal component scores-robust geographically weighted regression) receptor model was introduced to analyze the pollution sources of eight heavy metals (Cd, Hg, As, Pb, Ni, Cu, Zn) in a city of southern China. The results showed that source identification and source apportionment are more consistent by this advanced model even though the soil types and farming patterns are diverse. Moreover, this model decreased the occurrence of negative values of the source contribution. For these reasons, the pollution sources were classified into five types by the new model in the study area: agricultural sources, industrial sources, traffic sources, comprehensive sources, and natural sources. (1) The contributions of agricultural sources to Cr and Ni were 243.36% and 242.61%, respectively; (2) the contribution of industrial sources to Cd was 79.25%; (3) the contribution of traffic sources to Cu was 100.31%; (4) the contributions of comprehensive sources to Hg, Pb, and Zn were 253.90%, 242.31%, and 93.32%, respectively; and (5) the contribution of natural sources to As was 208.21%. Overall, the RAPCS-RGWR receptor model improved the validity of the receptor models. It is of great realistic significance to understand and popularize the advanced model in soil source apportionment in agricultural land.
Show more [+] Less [-]Does water temperature influence the distribution and elimination of perfluorinated substances in rainbow trout (Oncorhynchus mykiss)? Full text
2019
Vidal, Alice | Lafay, Florent | Daniele, Gaelle | Vulliet, Emmanuelle | Rochard, Eric | Garric, Jeanne | Babut, Marc
Does water temperature influence the distribution and elimination of perfluorinated substances in rainbow trout (Oncorhynchus mykiss)? Full text
2019
Vidal, Alice | Lafay, Florent | Daniele, Gaelle | Vulliet, Emmanuelle | Rochard, Eric | Garric, Jeanne | Babut, Marc
Perfluorinated and polyfluorinated substances (PFASs) are widely found in freshwater ecosystems because of their resistance to degradation and their ability to accumulate in aquatic organisms. While water temperature controls many physiological processes in fish, knowledge of the effects of this factor on PFAS toxicokinetic is still limited. This study presents experimental results of internal distribution and elimination rates of two perfluorinated acid compounds, namely perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS) in adult rainbow trout (Oncorhynchus mykiss) exposed to three temperatures. Dietary exposure experiments were conducted at 7 °C, 11 °C, and 19 °C and liver, blood, muscle, brain, and kidney were sampled for analysis. PFOS concentrations were comparable to or exceeded those of PFHxS, while PFHxS was eliminated faster than PFOS, whatever the temperature. Internal distribution changed significantly for both substances when fish were exposed to a range of temperatures from 7 to 19 °C. Indeed, PFOS and PFHxS relative distribution increased in blood, liver, and brain while they decreased in muscle when the water temperature rose. The water temperature variation affected the elimination half-lives, depending on the substances and organs.
Show more [+] Less [-]Does water temperature influence the distribution and elimination of perfluorinated substances in rainbow trout (Oncorhynchus mykiss)? Full text
2019
Vidal, Alice | Lafay, Florent | Danièle, Gaëlle | Vulliet, Emmanuelle | Rochard, Eric | Garric, Jeanne | Babut, Marc | RiverLy - Fonctionnement des hydrosystèmes ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | ISA-TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | Perfluorinated and polyfluorinated substances (PFASs) are widely found in freshwater ecosystems because of their resistance to degradation and their ability to accumulate in aquatic organisms. While water temperature controls many physiological processes in fish, knowledge of the effects of this factor on PFAS toxicokinetic is still limited. This study presents experimental results of internal distribution and elimination rates of two perfluorinated acid compounds, namely perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS) in adult rainbow trout (Oncorhynchus mykiss) exposed to three temperatures. Dietary exposure experiments were conducted at 7 °C, 11 °C, and 19 °C and liver, blood, muscle, brain, and kidney were sampled for analysis. PFOS concentrations were comparable to or exceeded those of PFHxS, while PFHxS was eliminated faster than PFOS, whatever the temperature. Internal distribution changed significantly for both substances when fish were exposed to a range of temperatures from 7 to 19 °C. Indeed, PFOS and PFHxS relative distribution increased in blood, liver, and brain while they decreased in muscle when the water temperature rose. The water temperature variation affected the elimination half-lives, depending on the substances and organs.
Show more [+] Less [-]Assessment of Pb2+ removal capacity of lichen (Evernia prunastri): application of adsorption kinetic, isotherm models, and thermodynamics Full text
2019
Şenol, Zeynep Mine | Gül, Ülküye Dudu | Şimşek, Selçuk
Biological materials play a significant role in the treatment of heavy metal-contaminated soil and wastewater. In this study, the Pb²⁺ biosorption potential of lichen Evernia prunastri, extensively available at a forest in Bilecik-Turkey, was investigated at batch-scale level. The optimal conditions were determined and the adsorption isotherms, kinetics, and thermodynamic calculations were also done. In order to have detailed knowledge about metal biosorption, SEM, FTIR, and BET analyses were carried out before and after the biosorption process. The optimal pH was found pH 4 and the maximum metal uptake capacity was found as 0.067 mol kg⁻¹. The results of this study indicate that the lichen was effectively applied to the removal of Pb²⁺ process as an inexpensive biosorbent from industrial wastewater.
Show more [+] Less [-]Chromium Speciation in Water Samples by Loading a New Sulfide-Containing Biodegradable Polymer Adsorbent in Tip of the Syringe System Full text
2019
Ali, Jamshed | Tuzen, Mustafa | Hazer, Baki | Kazi, Tasneem G.
A new adsorbent poly-3-hydroxybutyrate-2-(dodecylthiocarbonothioylthio)-2-methylpropionate triester (PH-DTT-MPT) was first time loaded in a micropipette tip for speciation of chromium in different water samples. Total chromium (Cr), trivalent chromium (Crᴵᴵᴵ), and hexavalent chromium (Crⱽᴵ) in different natural water samples were determined by electrothermal atomic absorption spectrometry. Known concentration of Crᴵᴵᴵ and Crⱽᴵ was passed through a biodegradable polymer for investigation of the behavior of the newly used adsorbent. The newly used copolymer absorbed the Crᴵᴵᴵ on surface of the PH-DTT-MPT at pH 7.0, while Crⱽᴵ was not adsorbed in desired pH value. After passing the real and standard solutions through the micropipette, then 2.0 mol L⁻¹ HCl was used for elution of Crᴵᴵᴵ from the biodegradable polymer. Total Cr was calculated after reducing Crⱽᴵ into Crᴵᴵᴵ by specific concentration of hydroxy ammonium chloride (HONH₂·HCl). The concentration of Crⱽᴵ in different natural water samples was estimated after back calculation of Crᴵᴵᴵ from total chromium. Effect of analytical parameters like adsorbent, pH, eluent, sample volume, flow rates, and interfering ions was also studied. The LOD, LOQ, RSD, and EF of the developed method were calculated as 6.1 ng L⁻¹, 20 ng L⁻¹, 1.17%, and 90, respectively. Validation of developed method was checked by certified reference materials and spiking addition method. The developed method was successfully applied for determination of total Cr, Crᴵᴵᴵ, and Crⱽᴵ in various natural water ecosystems.
Show more [+] Less [-]Body size variation of the ant Lasius niger along a metal pollution gradient Full text
2019
Grześ, Irena M. | Okrutniak, Mateusz | Gorzałczany, Monika | Piszczek, Piotr
Body size variation of the ant Lasius niger along a metal pollution gradient Full text
2019
Grześ, Irena M. | Okrutniak, Mateusz | Gorzałczany, Monika | Piszczek, Piotr
The phenotypic diversity of ant workers plays a fundamental role in their biology. In this study, we asked if the body size variation of monomorphic workers of the ant Lasius niger (Formicidae) responds adaptively to metal pollution in a post-mining metal-polluted area. Nest samples of workers were collected along a pollution gradient to calculate the within-colony variance in body size (expressed as maximum head width, HW). The results showed that the body size variation of L. niger was unrelated to the pollution index but demonstrated considerable variation between colonies even within the same study site. We suggest that the differences in morphological diversity between the colonies of L. niger could be shaped by colony personality traits, i.e., by colony-specific foraging and/or the feeding efficiency of nursing workers. The study supports previous findings, showing that morphological traits in Lasius ants are weakly related to environmental metal pollution.
Show more [+] Less [-]Body size variation of the ant Lasius niger along a metal pollution gradient Full text
Irena Grześ | Mateusz Okrutniak | Monika Gorzałczany | Piotr Piszczek
The phenotypic diversity of ant workers plays a fundamental role in their biology. In this study, we asked if the body size variation of monomorphic workers of the ant Lasius niger (Formicidae) responds adaptively to metal pollution in a post-mining metal-polluted area. Nest samples of workers were collected along a pollution gradient to calculate the within-colony variance in body size (expressed as maximum head width, HW). The results showed that the body size variation of L. niger was unrelated to the pollution index but demonstrated considerable variation between colonies even within the same study site. We suggest that the differences in morphological diversity between the colonies of L. niger could be shaped by colony personality traits, i.e., by colony-specific foraging and/or the feeding efficiency of nursing workers. The study supports previous findings, showing that morphological traits in Lasius ants are weakly related to environmental metal pollution. | Ants, Trace metals, Body size, Pollution, Adaptation, Colony personality | 100 | 17858-17864 | 17
Show more [+] Less [-]Equilibrium and Kinetic Study of Ammonium Sorption by Raphia farinifera Full text
2019
Staroń, Paweł | Sorys, Paulina | Chwastowski, Jarosław
The study investigated the sorption capacity of biosorbent-raphia sp. against ammonia. Raphia fibers were used without and with the modification of its surface with NaCl, NaNO₃, and K₂SO₄. The data was analyzed in the state of equilibrium using four isotherm models such as Langmuir, Freudlich, Temkin, and Dubinin-Radushkevich. The equilibrium of ammonia sorption for all studied systems was best described by the Freudlich isotherm model. On its basis, it can be assumed that the studied process is of chemical nature, which results from the value of the coefficient 1/n < 1. In order to confirm the sorption mechanism, analysis of the kinetics of the ammonia sorption process on raphia fibers was performed. Four kinetic models of sorption were calculated: pseudo-first-order model, pseudo-second-order model, Elovich model, and Webber-Morris intermolecular diffusion model. The sorption kinetics of the modeled ammonia waste were carried out using unmodified palm fibers and all kinds of surface modification. This process was best described by the pseudo-second-order sorption model, which can be considered as a confirmation of the chemical nature of ammonia sorption on raphia sp. fibers.
Show more [+] Less [-]Cyto(geno)toxicity of Commercial Fungicides Based on the Active Compounds Tebuconazole, Difenoconazole, Procymidone, and Iprodione in Lactuca sativa L. Meristematic Cells Full text
2019
Aragão, Francielen Barroso | Bernardes, Paula Mauri | Ferreira, Adésio | Ferreira, Marcia Flores da Silva | Andrade-Vieira, Larissa Fonseca
The present work aimed to evaluate the effects of commercial fungicides containing the active compounds from the triazole group—tebuconazole (TBZ) and difenoconazole (DFZ)—and dicarboximide group—procymidone (PRD) and iprodione (IPD) on the mitotic cycle of the plant model Lactuca sativa L. These active compounds have been present in foods sampled at different Brazilian’s states and amounted higher than recommended by law. The bioassay with L. sativa was applied to access the toxicity and better understand the mechanisms of action of these compounds in living beings. The active principles IPD and DFZ presented mitodepressive effect, statistically reducing the MI at all applied concentrations in comparison to the negative control. TBZ was the most cytotoxic active compound tested inhibited in 77% mitotic active in the lowest concentration applied. PRD alter the frequency of mitotic cells only in the concentration above that recommended by the manufacture. C-metaphase and adherent chromosomes were the most frequent cell cycle alteration observed on the treated cells, followed by bridges and lost chromosomes. Therefore, the mechanism of action was mainly aneugenic (70%). For TBZ, the frequency of condensed nucleus was very expressive (313 higher than the negative control).
Show more [+] Less [-]Co-culturing of oleaginous microalgae and yeast: paradigm shift towards enhanced lipid productivity Full text
2019
Arora, Neha | Patel, Alok | Mehtani, Juhi | Pruthi, Parul A | Pruthi, Vikas | Poluri, Krishna Mohan
Oleaginous microalgae and yeast are the two major propitious factories which are sustainable sources for biodiesel production, as they can accumulate high quantities of lipids inside their bodies. To date, various microalgal and yeast species have been exploited singly for biodiesel production. However, despite the ongoing efforts, their low lipid productivity and the high cost of cultivation are still the major bottlenecks hindering their large-scale deployment. Co-culturing of microalgae and yeast has the potential to increase the overall lipid productivity by minimizing its production cost as both these organisms can utilize each other’s by-products. Microalgae act as an O₂ generator for yeast while consuming the CO₂ and organic acids released by the yeast cells. Further, yeast can break complex sugars in the medium, which can then be utilized by microalgae thereby opening new options for copious and low-cost feedstocks such as agricultural residues. The current review provides a historical and technical overview of the existing studies on co-culturing of yeast and microalgae and elucidates the crucial factors that affect the symbiotic relationship between these two organisms. Furthermore, the review also highlighted the advantages and the future perspectives for paving a path towards a sustainable biodiesel product.
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