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Contamination level, distribution and health risk assessment of heavy and toxic metallic and metalloid elements in a cultivated mushroom Pleurotus florida (Mont.) singer Full text
2017
Khani, Rouhollah | Moudi, Maryam | Khojeh, Vahid
There are great concentrations of toxic metallic and metalloid elements such as lead, arsenic, mercury, cadmium or silver in many species of mushrooms comparative to other fruits and vegetables. In this study, contamination with heavy and toxic metallic and metalloid elements in the cultivated mushroom of (Pleurotus florida (Mont.) Singer) is investigated. P. florida was cultivated on different substrates; wheat straw (as blank), wheat straw + pine cone, wheat straw + soybean straw and wheat straw + urea and the effects of these substrates on contamination levels of Mn, Fe, Cu, Zn, As, Cd, and Pb were analyzed. The results showed that the concentrations of essential elements (Mn, Fe, Cu, and Zn) in the target mushroom are at the typical levels. The estimated daily intakes of studied metallic and metalloid elements were below their oral reference dosage mentioned by the international regulatory bodies. Health risk index (HRI) was calculated to evaluate the consumer’s health risk assessment from the metal intake that contaminated in the cultivated mushroom of P. florida on the different nutrient sources. In this study, the individual HRIs were less than 1, which indicates insignificant potential health risk associated with the consumption of target mushroom from the studied substrates. Based on the HRIs values among the toxic metallic and metalloid elements, As in the target mushroom in the substrate of the wheat straw + pine cone is the main sources of risk, and it may cause severe health problems. Thus, this study suggests that the concentrations of heavy and toxic elements should be periodically monitored in cultivated mushrooms.
Show more [+] Less [-]Bio-transfer factors and temporal variation of heavy metals in different sexes of three species of edible brackish water fish Full text
2017
Kularatne, Ranil Kavindra Asela | Harris, Jalaldeen Mohamed | Vinobaba, Periyathamby | Kankanamge, Champika Ellawala
This article discusses bioaccumulation and temporal variation of heavy metals in three edible lagoon fish species with references to gender. Cd and As were undetected in the three fish species (i.e., below the method detection limits of 1 μg Cd/kg wet weight and 2 μg As/kg wet weight) irrespective of the periods, and Cd was undetected in the water too (i.e., below the detection limit of 0.0003 mg/L). Except for Zn (which was mainly available as Zn²⁺ in the water), Pb was present largely as low labile metal-chloride complexes and As as HAsO₄ ²⁻ as per Visual MINTEQ, version 3.1. Bio-transfer factors of Sn (which was also undetected in the water; below the detection limit of 0.05 mg/L), Hg, Pb, and Zn were <1 in both sexes, justifying that bioaccumulation was largely attributed to food rather than uptake from the water. Metal accumulation patterns differed drastically between the fish species. Arius maculatus (a carnivore) exhibited higher Zn, Hg, and Sn accumulations during the drier periods (June–September) compared with Mugil cephalus (a detritivore/herbivore) and Etroplus suratensis (an omnivore). Pb was detected only in A. maculatus (July–August) possibly due to biomagnification. Zn was present in higher levels in all species (irrespective of sex) compared with the other metals, but levels were below admissible limits. However, the relationship between temporal variation of Zn and gender in all species was insignificant. In M. cephalus, the temporal variation of Sn and Hg between the sexes was also insignificant. Female A. maculatus and E. suratensis showed higher Hg concentrations, while males showed higher Sn concentrations. Temporal variation patterns of Pb were unclear.
Show more [+] Less [-]The efficiency of the multi-walled carbon nanotubes used for antibiotics removal from wastewaters generated by animal farms Full text
2017
Soran, Maria-Loredana | Opriş, Ocsana | Lung, Ildikó | Kacso, Irina | Porav, Alin S. | Stan, Manuela
In the recent years, residual antibiotics are considered to be emerging environmental pollutants due to their continuous input and persistence into the aquatic ecosystem even at low concentrations. Therefore, these are necessary to develop efficient methods for the wastewater treatment. The present paper describes the efficiency of several types of multi-walled carbon nanotubes (MWCNTs) for the retention of the selected antibiotics (ampicillin, ceftazidime, cefepime, imipenem, piperacillin, tazobactam, tetracycline, erythromycin, ciprofloxacin, norfloxacin, vancomycin, gentamicin, sulfamethoxazole, and thrimetoprim) from aqueous (synthetic) solutions and wastewater samples. The functionalized MWCNTs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The obtained antibiotic percentage of retention was evaluated by quantitative assessment using high-performance liquid chromatography coupled with the diode array, fluorescence, and mass spectrometer detector (HPLC-DAD/FD/MS), after the solid-phase extraction (SPE) with Oasis HLB cartridges. The retention percentages of the selected antibiotics from waters ranged between ∼40 and 97%, with the exception of sulfamethoxazole and trimethoprim. The best percentages of retention were obtained for norfloxacin 97.03% and ciprofloxacin 97.10%. The suspensions of the MWCNTs improved the antibiotics removal from wastewaters. Removal of antibiotics from wastewaters using nanotechnology, in order to reduce their negative effects and antibiotic resistance, is a promising tool in the future wastewaters treatment.
Show more [+] Less [-]Metal transport and remobilisation in a basin affected by acid mine drainage: the role of ochreous amorphous precipitates Full text
2017
Consani, Sirio | Carbone, Cristina | Dinelli, Enrico | Balić-Žunić, Tonci | Cutroneo, Laura | Capello, Marco | Salviulo, Gabriella | Lucchetti, Gabriella
Metal-polluted mine waters represent a major threat to the quality of waters and sediments in a downstream basin. At the confluence between acidic mine waters and the unpolluted waters of the Gromolo Torrent (Liguria, North-West Italy), the massive formation of an ochreous amorphous precipitate takes place. This precipitate forms a soft blanket that covers the torrent bed and can be observed down to its mouth in the sea. The aim of this work is to evaluate the dispersion of metals in the Gromolo Torrent basin from the abandoned Cu-Fe sulphide mine of Libiola to the Ligurian Sea and to assess the metal remobilisation from the amorphous precipitates. The mineralogy of the superficial sediments collected in the torrent bed and the concentrations of different elements of environmental concern (Cu, Zn, Cd, Co, Cr, Mn, Ni, Pb, As, and Sb) were therefore analysed. The results showed that the precipitates contain high concentration of Fe, Al, Cu, and Zn, significantly modifying the bulk chemistry of the Gromolo Torrent sediments. In order to evaluate the possible remobilisation of ecotoxic elements from the amorphous precipitates, bulk leaching tests were performed with both deionised and seawater. Bulk leaching tests with deionised water mobilised primarily high Pb amounts, but also relatively high concentrations of Fe, Al, Cu, and Zn are released in the leachate. In seawater tests, Fe, Al, Cu, and Zn were released in smaller amounts, while other elements like Mn, Cd, Co, and Ni increased in the released fraction. Pb was still strongly released as in deionised water experiments. The results show that the interaction of precipitates and seawater can remobilise high concentrations of metals, thus affecting the surrounding environment.
Show more [+] Less [-]Caregivers had neighbourhood support but perceived it unsatisfactory and worsened: England Community Life Survey, 2012–2014 Full text
2017
Shiue, Ivy
There has been limited research studying neighbourhood support for caregivers. Therefore, the aim of the present study was to investigate the support from neighbourhoods between both caregivers and non-caregivers in a country-wide and population-based setting. Data were retrieved from England Community Life Survey, 2012–2014, a new annual household survey conducted by face-to-face interview since 2012, with a representative sample size of 5–6000 adult (aged 16 years and over) resident per year in England. Chi-square test and logistic regression modelling were performed to examine the variance in support from and perception toward neighbourhoods between caregivers and non-caregivers. Of 15,320 study participants, 2315 (16.0%) had a caring responsibility. There was not much variance in feeling belonging, comfortably asking neighbours to keep keys, comfortably asking neighbours to mind children, believing neighbours pulling together and trusting people in the neighbourhood between caregivers and non-caregivers. However, caregivers seemed to be more likely to chat to neighbours (OR 0.77, 95% CI 0.69–0.87, P < 0.001) and comfortably ask neighbours to help collect grocery (OR 0.89, 95% CI 0.81–0.98, P = 0.023). In addition, caregivers tended to perceive their neighbourhoods unsatisfactory (OR 1.17, 95% CI 1.05–1.32, P = 0.007) and worsened in the last 2 years (OR 1.36, 95% CI 1.22–1.51, P < 0.001). For future research, a longitudinal neighbourhood monitoring surveillance for all people would be suggested. For practice and policy, environmental health and nursing programs might need to extend education trainings and interventions to cover all neighbourhoods at different time points that can lessen both disease and caregiving burden and therefore optimize health and quality of life.
Show more [+] Less [-]Environmental impact assessments of the Xiaolangdi Reservoir on the most hyperconcentrated laden river, Yellow River, China Full text
2017
Kong, Dongxian | Miao, Chiyuan | Wu, Jingwen | Borthwick, Alistair G.L. | Duan, Qingyun | Zhang, Xiaoming
The Yellow River is the most hyperconcentrated sediment-laden river in the world. Throughout recorded history, the Lower Yellow River (LYR) experienced many catastrophic flood and drought events. To regulate the LYR, a reservoir was constructed at Xiaolangdi that became operational in the early 2000s. An annual water–sediment regulation scheme (WSRS) was then implemented, aimed at flood control, sediment reduction, regulated water supply, and power generation. This study examines the eco-environmental and socioenvironmental impacts of Xiaolangdi Reservoir. In retrospect, it is found that the reservoir construction phase incurred huge financial cost and required large-scale human resettlement. Subsequent reservoir operations affected the local geological environment, downstream riverbed erosion, evolution of the Yellow River delta, water quality, and aquatic biodiversity. Lessons from the impact assessment of the Xiaolangdi Reservoir are summarized as follows: (1) The construction of large reservoirs is not merely an engineering challenge but must also be viewed in terms of resource exploitation, environmental protection, and social development; (2) long-term systems for monitoring large reservoirs should be established, and decision makers involved at national policy and planning levels must be prepared to react quickly to the changing impact of large reservoirs; and (3) the key to solving sedimentation in the LYR is not Xiaolangdi Reservoir but instead soil conservation in the middle reaches of the Yellow River basin. Proper assessment of the impacts of large reservoirs will help promote development strategies that enhance the long-term sustainability of dam projects.
Show more [+] Less [-]Procedures of determining organic trace compounds in municipal sewage sludge—a review Full text
2017
Lindholm-Lehto, Petra C. | Ahkola, Heidi S. J. | Knuutinen, Juha S.
Sewage sludge is the largest by-product generated during the wastewater treatment process. Since large amounts of sludge are being produced, different ways of disposal have been introduced. One tempting option is to use it as fertilizer in agricultural fields due to its high contents of inorganic nutrients. This, however, can be limited by the amount of trace contaminants in the sewage sludge, containing a variety of microbiological pollutants and pathogens but also inorganic and organic contaminants. The bioavailability and the effects of trace contaminants on the microorganisms of soil are still largely unknown as well as their mixture effects. Therefore, there is a need to analyze the sludge to test its suitability before further use. In this article, a variety of sampling, pretreatment, extraction, and analysis methods have been reviewed. Additionally, different organic trace compounds often found in the sewage sludge and their methods of analysis have been compiled. In addition to traditional Soxhlet extraction, the most common extraction methods of organic contaminants in sludge include ultrasonic extraction (USE), supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), and pressurized liquid extraction (PLE) followed by instrumental analysis based on gas or liquid chromatography and mass spectrometry.
Show more [+] Less [-]The impact of two fluoropolymer manufacturing facilities on downstream contamination of a river and drinking water resources with per- and polyfluoroalkyl substances Full text
2017
Bach, Christina | Dauchy, Xavier | Boiteux, Virginie | Colin, Adeline | Hemard, Jessica | Sagres, Véronique | Rosin, Christophe | Munoz, Jean-François
Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are emerging contaminants that have been detected in the environment, biota, and humans. Drinking water is a route of exposure for populations consuming water contaminated by PFAS discharges. This research study reports environmental measurement concentrations, mass flows, and the fate of dozens of PFASs in a river receiving effluents from two fluoropolymer manufacturing facilities. In addition to quantified levels of PFASs using LC- and GC-MS analytical methods, the total amount of unidentified PFASs and precursors was assessed using two complementary analytical methods, absorbable organic fluorine (AOF) determination and oxidative conversion of perfluoroalkyl carboxylic acid (PFCA) precursors. Several dozen samples were collected in the river (water and sediment) during four sampling campaigns. In addition, samples were collected in two well fields and from the outlet of the drinking water treatment plants after chlorination. We estimated that 4295 kg PFHxA, 1487 kg 6:2FTSA, 965 kg PFNA, 307 kg PFUnDA, and 14 kg PFOA were discharged in the river by the two facilities in 2013. High concentrations (up to 176 ng/g dw) of odd long-chain PFASs (PFUnDA and PFTrDA) were found in sediment samples. PFASs were detected in all 15 wells, with concentrations varying based on the location of the well in the field. Additionally, the presence of previously discharged PFASs was still measurable. Significant discrepancies between PFAS concentration profiles in the wells and in the river suggest an accumulation and transformation of PFCA precursors in the aquifer. Chlorination had no removal efficiency and no unidentified PFASs were detected in the treated water with either complementary analytical method. Although the total PFAS concentrations were high in the treated water, ranging from 86 to 169 ng/L, they did not exceed the currently available guideline values.
Show more [+] Less [-]The characteristics of steel slag and the effect of its application as a soil additive on the removal of nitrate from aqueous solution Full text
2017
Liyun, Yang | Ping, Xu | Maomao, Yang | Hao, Bai
This study examined the characteristics of nitrate removal from aqueous solution by steel slag and the feasibility of using steel slag as a soil additive to remove nitrate. Steel slag adsorbents were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and infrared spectrum (IR spectrum). Adsorption isotherms and kinetics were also analysed. Various parameters were measured in a series of batch experiments, including the sorbent dose, grain size of steel slag, reaction time, initial concentration of nitrate nitrogen, relationship between Al, Fe and Si ions leached from the steel slag and residual nitrate in the aqueous solution. The nitrate adsorbing capacity increased with increasing amounts of steel slag. In addition, decreasing the grain diameter of steel slag also enhanced the adsorption efficiency. Nitrate removal from the aqueous solution was primarily related to Al, Fe, Si and Mn leached from the steel slag. The experimental data conformed to second-order kinetics and the Freundlich isothermal adsorption equation, indicating that the adsorption of nitrate by steel slag is chemisorption under the action of monolayer adsorption. Finally, it was determined that using steel slag as a soil additive to remove nitrate is a feasible strategy.
Show more [+] Less [-]Evaluation of various solvent systems for lipid extraction from wet microalgal biomass and its effects on primary metabolites of lipid-extracted biomass Full text
2017
Ansari, Faiz Ahmad | Gupta, Sanjay Kumar | Shriwastav, Amritanshu | Guldhe, Abhishek | Rawat, Ismail | Bux, F. (Faizel)
Microalgae have tremendous potential to grow rapidly, synthesize, and accumulate lipids, proteins, and carbohydrates. The effects of solvent extraction of lipids on other metabolites such as proteins and carbohydrates in lipid-extracted algal (LEA) biomass are crucial aspects of algal biorefinery approach. An effective and economically feasible algae-based oil industry will depend on the selection of suitable solvent/s for lipid extraction, which has minimal effect on metabolites in lipid-extracted algae. In current study, six solvent systems were employed to extract lipids from dry and wet biomass of Scenedesmus obliquus. To explore the biorefinery concept, dichloromethane/methanol (2:1 v/v) was a suitable solvent for dry biomass; it gave 18.75% lipids (dry cell weight) in whole algal biomass, 32.79% proteins, and 24.73% carbohydrates in LEA biomass. In the case of wet biomass, in order to exploit all three metabolites, isopropanol/hexane (2:1 v/v) is an appropriate solvent system which gave 7.8% lipids (dry cell weight) in whole algal biomass, 20.97% proteins, and 22.87% carbohydrates in LEA biomass. Graphical abstract: Lipid extraction from wet microalgal biomass and biorefianry approach
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