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Occurrence and assessment of environmental risks of endocrine disrupting compounds in drinking, surface and wastewaters in Serbia
2020
Čelić, Mira | Škrbić, Biljana D. | Insa, Sara | Živančev, Jelena | Gros, Meritxell | Petrović, M. (Mira)
The present study is the first comprehensive monitoring of 13 selected endocrine disrupting compounds (EDCs) in untreated urban and industrial wastewater in Serbia to assess their impact on the Danube River basin and associated freshwaters used as sources for drinking water production in the area. Results showed that natural and synthetic estrogens were present in surface and wastewater at concentrations ranging from 0.1 to 64.8 ng L⁻¹. Nevertheless, they were not detected in drinking water. For alkylphenols concentrations ranged from 1.1 to 78.3 ng L⁻¹ in wastewater and from 0.1 to 37.2 ng L⁻¹ in surface water, while in drinking water concentrations varied from 0.4 to 7.9 ng L⁻¹. Bisphenol A (BPA) was the most abundant compound in all water types, with frequencies of detection ranging from 57% in drinking water, to 70% in surface and 84% in wastewater. Potential environmental risks were characterized by calculating the risk quotients (RQs) and the estrogenic activity of EDCs in waste, surface and drinking water samples, as an indicator of their potential detrimental effects. RQ values of estrone (E1) and estradiol (E2) were the highest, exceeding the threshold value of 1 in 60% of wastewater samples, while in surface water E1 displayed potential risks in only two samples. Total estrogenic activity (EEQₜ) surpassed the threshold of 1 ng E2 L⁻¹ in about 67% of wastewater samples, and in 3 surface water samples. In drinking water, EEQₜ was below 1 ng L⁻¹ in all samples.
Show more [+] Less [-]Emerging concerns of VOCs and SVOCs in coking wastewater treatment processes: Distribution profile, emission characteristics, and health risk assessment
2020
Saber, Ayman N. | Zhang, Haifeng | Cervantes-Avilés, Pabel | Islam, Ashraful | Gao, Yingxin | An, Wei | Yang, Min
In this study, the distribution profiles, emission characteristics, and health risks associated with 43 volatile and semi-volatile organic compounds, including 15 phenols, 18 polycyclic aromatic hydrocarbons (PAHs), 6 BTEX, and 4 other compounds, were determined in the wastewater treatment plant (WWTP) of a coking factory (plant C) and the succeeding final WWTP (central WWTP). Total phenols with a concentration of 361,000 μg L⁻¹ were the predominant compounds in the influent wastewater of plant C, whereas PAHs were the major compounds in the final effluents of both coking WWTPs (84.4 μg L⁻¹ and 30.7 μg L⁻¹, respectively). The biological treatment process in plant C removed the majority of volatile organic pollutants (94.1%–99.9%). A mass balance analysis for plant C showed that biodegradation was the main removal pathway for all the target compounds (56.6%–99.9%) except BTEX, chlorinated phenols, and high molecular weight (MW) PAHs. Chlorinated phenols and high MW PAHs were mainly removed via sorption to activated sludge (51.8%–73.2% and 60.2%–75.9%, respectively). Air stripping and volatilization were the dominant mechanisms for removing the BTEX compounds (59.8%–73.8%). The total emission rates of the detected volatile pollutants from plant C and the central WWTP were 1,640 g d⁻¹ and 784 g d⁻¹, respectively. Benzene from the equalization basins of plant C and the central WWTP corresponded to the highest inhalation carcinogenic risks (1.4 × 10⁻³ and 3.2 × 10⁻⁴, respectively), which exceeded the acceptable level for human health (1 × 10⁻⁶) recommended by the United States Environmental Protection Agency. The results showed that BaP exhibited the highest inhalation non-cancer risk, with a hazard index ratio of 70 and 30 for plant C and the central WWTP, respectively. Moreover, the excess sludge generated during wastewater treatment should also be carefully handled because it adsorbed abundant PAHs and chlorinated phenols at coking plant C (58,000 μg g⁻¹ and 3,500 μg g⁻¹) and the central WWTP (622 μg g⁻¹ and 54 μg g⁻¹).
Show more [+] Less [-]Phytoremediation of polluted soils and waters by native Qatari plants: Future perspectives
2020
Al-Thani, R.F. | Yasseen, B.T.
Because pollution is predicted to worsen and sources of quality water for agriculture and other human activities are limited, many countries have been motivated to seek novel water sources. Qatar relies on groundwater and water desalinization to meet its water needs, and additional water resources will be needed to avoid unexpected crises in the future. Industrial wastewater (IWW) is an alternative water source, and much research activities should be focused on developing innovative and contemporary approaches to removing pollutants from IWW. Phytoremediation methods, shown to be efficient methods of removing and degrading contaminants of various kinds from polluted waters and soils, require knowledge of the native plants and associated microorganisms. In Qatar, many native plants (monocot and dicot, indigenous or introduced) have been shown to be greatly effective in remediating polluted areas. This article is a guide for Qatari scientists aiming to identify promising native plants and associated microbes for IWW phytoremediation. In it, we review the basic components of bioremediation and summarize the principle phytoremediation approaches and preferred recycling options. The multiple mechanisms and methods of phytoremediation for cleansing polluted soils and waters are also discussed as are details of the metabolic reactions degrading the organic components of oil and gas. Finally, heavy metal accumulation is addressed. Wastewater from industrial and domestic activities is currently being used to create green areas around Doha, Qatar, and such areas could be at risk of contamination. Many native Qatari plants and soil-dwelling microbes are efficient at removing organic and inorganic contaminants from polluted soils and waters, and some are promising candidates for achieving a clean environment free of contaminants.
Show more [+] Less [-]A new thermoanalytical method for the quantification of microplastics in industrial wastewater
2020
Mallow, Ole | Spacek, Stefan | Schwarzböck, Therese | Fellner, Johann | Rechberger, Helmut
Plastics are crucial for our modern lifestyle and yet pose a major threat to our environment. Rising levels of microplastics (MP) in rivers and oceans are a big challenge for our economy and regulatory institutions as well as from a scientific point of view. Smaller microplastic particles, in particular, are especially hard to identify and even harder to quantify in environmental samples. Hence, we present a novel and inexpensive approach to quantify microplastics (MP) on a weight basis, relying on a thermoanalytical method. The Elemental Analysis combined with Overdetermined Equation Method (EA-OEM) was originally developed for determining the plastic content of refuse-derived fuels. It makes use of the distinct differences in the organic elemental composition (C, H, N, S, O) of plastics, biogenic and inorganic materials to calculate the (micro)plastic content on a detailed weight base. The study presented provides the first experimental results yielded from the application of the EA-OEM and two different laboratory approaches to the analysis of polyethylene (PE) and polypropylene (PP) MP content in industrial effluent samples from one source. In this way, it was possible to ensure that the polymer composition was known and the MP content therein (10–29%) could be derived. Further, the study reveals good MP recovery rates when applying the methodology to PE/PP-spiked samples.
Show more [+] Less [-]Geo-environmental assessment of heavy metals in the bottom sediments of the Southern Corniche of Jeddah, Saudi Arabia
2020
Bantan, Rashad A. | Al-Dubai, Talha A. | Al-Zubieri, Aaid G.
The Southern Corniche of Jeddah (SCJ) is located on the centre of the eastern Red Sea coast, Saudi Arabia and is increasingly affected by many anthropogenic activities, making it vulnerable to pollution. Sixty-three sediments and water samples were examined in regard to environmental parameters (temperature, salinity, dissolved oxygen (DO) and pH), grain size, organic matter (OM) and carbonate content and metals concentrations (Fe, Mn, Cu, Pb, Cr, Zn, Ni, and Co) in order to assess the level of contamination in SCJ's bottom sediment. The results showed that the highest concentrations of heavy metals in the shoreline and Lagoon areas are mainly due to the influx of domestic and industrial wastewater into the area where they were correlated with mud, OM, salinity and pH. The contamination factor (CF) for Fe and Co in the bottom sediments exhibited higher values than the threshold 3 value, particularly in the Lagoon and Al-Budhai area. The pollution load index (PLI) values of sediment samples could be classified as contaminated samples, especially in the nearshore samples indicating an increase of metals accumulation with decreasing distance from the source area. PCA has shown that Fe and Mn are positively correlated with all heavy metals, probably due to their high adsorption capacity in the presence of DO. The metals were Normalized with Fe, it was found that the bottom sediments of the SCJ could be reported as metal contaminated and mainly affected by natural and human sources.
Show more [+] Less [-]Chemical fractionation and risk assessment of trace elements in sewage sludge generated from various states of Pakistan
2020
Riaz, Umair | Murtaza, Ghulam | Saifullah, | Fārūq, Muḥammad | Aziz, Humera | Qadir, Ayesha Abdul | Mehdi, Shahzada Munawar | Qazi, Muhammad Akram
In the developing world, rapid urbanization and industrialization produces an enormous volume of wastes daily. This study was aimed to explore the potential and risks associated with sewage sludge through the characterization and fractionation technique. Sewage sludge samples were collected from various wastewater treatment in five different cities of Pakistan. Considerable amounts of macro-elements were detected in all types of sewage sludge samples. The pHw of all sewage sludge were neutral to slightly alkaline in reaction. Total organic carbon (TOC) was maximum (18.73%) with Coca-Cola sewage sludge (CSS) while the minimum (14.69%) was with Water and Sanitation Agency (WASA) sewage sludge (WSS). Percent relative distribution of cadmium (Cd) was higher in residual fraction (F4) up to 52% in the Nestle wastewater treatment plant, Sheikhupura (NSS). The chromium (Cr) concentration in Kasur sewage sludge (KSS) was extremely in mobile fraction (exchangeable) as compared with all other sludge samples, therefore showing a higher level of risk assessment code. While in the case of Iron (Fe), mobility was less and its maximum portion was noted in residual fraction (F4) of all sewage sludge samples. Percent distribution of manganese (Mn) showed variable trends for different sewage sludge samples. Zinc (Zn) concentration showed high mobility (exchangeable fraction) in case of NUST wastewater treatment plant, Islamabad (NTS) (31.16%) and WSS (37.83%) as compared with other sewage sludges. The risk assessment code indicated that Zn and Ni had a medium level of risk with I-9 Sector wastewater treatment plant, Islamabad (ISS), CSS, KSS, and NSS whereas these pose a high risk with NTS and WSS. Based on physicochemical properties, nutrients, trace elements, mobility, and risk assessment code, it was concluded that KSS should not be recommended at any application rate while NTS and WSS may be used at low application rates whereas ISS, CSS, and NSS may be used for agricultural crop production.
Show more [+] Less [-]Improved filtration for dye removal using keratin–polyamide blend nanofibrous membranes
2020
David, Padma Sheeba | Karunanithi, Arthi | Fathima, Nishter Nishad
Dyes from industrial wastewaters represent one of the most hazardous pollutants as they are not effectively biodegradable. The present work is focused to study the novel properties of keratin-polyamide blend nanofibrous filtration membranes for treating wastewaters containing dye. Keratin protein was extracted from goat hair, a tannery waste through sulphitolysis process. The extracted keratin was blended with polyamide to prepare a nanofibrous membrane through the electrospinning process. The fabricated pristine polyamide and keratin-altered polyamide membranes were characterized and compared for their properties. Effects of solution pH, dye concentration, membrane flux, and membrane capacity have been examined. Very fine nanofibers and enhanced porosity drive the membrane to enhanced flux and higher filtration efficiencies. At pH 2, the dye removal efficiency of the blend membranes was 100, 99, 98, 90, and 83% for 100, 200, 250, 300, and 400 ppm concentrations of dye, respectively. The keratin–polyamide blend membrane exhibited better properties in all aspects. The results of this present investigation indicate that the presence of keratin in filtration membranes is promising for dye removal from the effluents.
Show more [+] Less [-]Treatment of wastewater from petroleum industry: current practices and perspectives
2020
Varjani, Sunita | Joshi, Rutu | Srivastava, V. K. (Vijay Kumar) | Ngo, Huu Hao | Guo, Wenshan
Petroleum industry is one of the fastest growing industries, and it significantly contributes to economic growth in developing countries like India. The wastewater from a petroleum industry consist a wide variety of pollutants like petroleum hydrocarbons, mercaptans, oil and grease, phenol, ammonia, sulfide, and other organic compounds. All these compounds are present as very complex form in discharged water of petroleum industry, which are harmful for environment directly or indirectly. Some of the techniques used to treat oily waste/wastewater are membrane technology, photocatalytic degradation, advanced oxidation process, electrochemical catalysis, etc. In this review paper, we aim to discuss past and present scenario of using various treatment technologies for treatment of petroleum industry waste/wastewater. The treatment of petroleum industry wastewater involves physical, chemical, and biological processes. This review also provides scientific literature on knowledge gaps and future research directions to evaluate the effect(s) of various treatment technologies available.
Show more [+] Less [-]Study on the interactive influence between economic growth and environmental pollution
2020
Rao, Congjun | Yan, Bangjie
With the rapid growth of economy, the environmental pollution problem is becoming increasingly prominent. How to promote the coordinated and balanced development of economy and environment is a strategic problem of great significance that we face urgently. Taking Wuhan City of China as the research object, this paper selects the key indexes of economic growth and environmental pollution and studies the interactive influence between economic growth and environmental pollution in Wuhan. On the one hand, the impact of Wuhan’s economic growth on environmental pollution is analyzed by the proposed time-delay correlation analysis method and the time-delay EKC (Environment Kuznets Curve) models. On the other hand, the impact of Wuhan’s environmental pollution on environmental growth is studied. By establishing the LARS-LASSO (least angle regression-least absolute shrinkage and selection operator) regression model and the stepwise regression model, the main factors affecting economic growth in preliminary environmental pollution indexes are analyzed, and then, an interaction model is established to study the impact of the interaction between any two main environmental factors on economic growth. The results of empirical analysis show that the main factors affecting economic growth are industrial wastewater emissions, industrial waste gas emissions, and industrial smoke and dust emissions, and the interaction between industrial waste gas emissions and industrial wastewater emissions restrains economic growth.
Show more [+] Less [-]Biosorption of Cr(VI) by Halomonas sp. DK4, a halotolerant bacterium isolated from chrome electroplating sludge
2020
Kalola, Vidhi | Desai, Chirayu
This study evaluated Cr(VI) biosorption by a halotolerant gram-negative bacterium Halomonas sp. DK4 isolated from chrome electroplating sludge. The bacterium could withstand high concentrations of Cr(VI) exhibiting a minimal inhibitory concentration (MIC) of 250 mg/L. Plackett–Burman design confirmed glucose, KH₂PO₄, NaCl, inoculum size, and initial Cr(VI) concentration as significant variables influencing the Cr(VI) removal ability of the bacterium. The suspended culture of Halomonas sp. DK4 was able to remove 81% (100 mg/L) of Cr(VI) in optimized MSM medium from aqueous solutions within 48 h. The bacterium also removed 59% Cr(VI) in the presence of 15% NaCl concentration within 72 h. The main mechanism involved in Cr(VI) removal by Halomonas sp. DK4 was determined to be biosorption which was best explained using the Langmuir isotherm model, wherein the maximum adsorption of 150.7 mg/g was observed under equilibrium conditions. Kinetic studies reveal that chemisorption of Cr(VI) by Halomonas sp. DK4 was a rate-limiting process which followed pseudo-second-order kinetics (R² = 0.99). Bacterial biomass exhibited maximum adsorption of 70.3% Cr(VI) at an initial concentration of 100 mg/L under optimal conditions. Fourier transform infrared spectroscopy (FTIR) analysis confirmed the presence of hydroxyl, carboxyl, amide, and phosphate groups on the bacterial surface which may be involved in Cr(VI) adsorption. Scanning electron microscopy coupled energy dispersive X-ray (SEM-EDX) analysis revealed morphological changes in the bacterial cell and accumulation of Cr(VI) on the cell surface. These results suggest the potential application of Halomonas sp. DK4 in the removal of Cr(VI) from saline chromium-containing industrial wastewaters.
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