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Anaerobic treatment of wastewaters from alcohol and yeast factories
1999
Klasnja, M. | Sciban, M. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). Tehnoloski fakultet)
Alcohol and yeast production is the most important part of the biotechnological production in Yugoslavia, with annual production of 13 667 867 liters of absolute alcohol and of 20 947 490 kg of yeast in the year 1998. Large environmental load is produced by wastewaters from alcohol and yeast factories (512 000 P.E.), especially by alcohol stillage (BOD 40 000 - 50 000 mg/L). Anaerobic treatment is suitable process for treatment of alcohol stillage, and of yeast factory wastewater. In this paper, effects of treatment process (organic load reduction, energy of produced biogas) are discussed; and potential of anaerobic treatment os wastewaters from Yugoslavia's alcohol and yeast factories is reviewed.
显示更多 [+] 显示较少 [-]Short-term ambient particulate air pollution exposure, microRNAs, blood pressure and lung function
2022
Cong, Xiaowei | Zhang, Juan | Sun, Rongli | Pu, Yuepu
Ambient particulate air pollution is a risk factor for cardiovascular and respiratory disease, yet the biological mechanisms underlying this association are not well understood. The current study aimed to investigate the mediation role of microRNAs on the association between personal PM₂.₅ exposure and blood pressure and lung function. One hundred and twenty adults (60 truck drivers and 60 office workers) aged 18–46 years were assessed on the June 15, 2008 and at follow-up (1- to 2-weeks later). MicroRNAs were extracted from the peripheral blood samples. Compared to truck drivers, there is a significant increase in FEF₂₅₋₇₅, FEV₁, and FEV₁/FVC and a decrease in PM₂.₅ in office workers (all p < 0.05). According to the Bonferroni corrected threshold p-value < 6.81 × 10⁻⁵ (0.05/734) used, personal PM₂.₅ data showed a significant positive association with miR-644 after the adjustment for age, BMI, smoking status, and habitual alcohol use. The mediation effect of miR-644 on the association between personal PM₂.₅ exposure and FEF₂₅₋₇₅ [B (95%CI) = −1.342 (−2.810, −0.113)], PEF [B (95%CI) = -1.793 (−3.926, −0.195)], and FEV₁/FVC [B (95%CI) = −0.119‰ (−0.224‰, −0.026‰)] was significant only for truck drivers after the adjustment for covariates. There were no similar associations with blood pressure. These results demonstrate microRNAs to potentially mediate association of PM₂.₅ with lung function. Subsequent studies are needed to further elucidate the potential mechanisms of action by which the mediation effect of microRNAs is achieved with this process.
显示更多 [+] 显示较少 [-]Enhanced treatment of organic matter in slaughter wastewater through live Bacillus velezensis strain using nano zinc oxide microsphere
2022
Deng, Jing | Jia, Mingxi | Zeng, Yu Qing | Li, Wen | He, JinTao | Ren, Jiali | Bai, Jie | Zhang, Lin | Li, Juan | Yang, Sheng
Slaughter wastewater is an important and wide range of environmental issues, and even threaten human health through meat production. A high efficiency and stability microsphere-immobilized Bacillus velezensis strain was designed to remove organic matter and inhibit the growth of harmful bacteria in process of slaughter wastewater. Bacillus velezensis was immobilized on the surface of sodium alginate (SA)/Polyvinyl alcohol (PVA)/Nano Zinc Oxide (Nano-ZnO) microsphere with the adhesion to bio-carrier through direct physical adsorption. Results indicated that SA/PVA/ZnO and SA/ZnO microspheres could inhibit E.coli growth with adding 0.15 g/L nano-ZnO and not affect Bacillus velezensis strain, and the removal the chemical oxygen demand (COD) rates of SA/PVA/ZnO microsphere immobilized cells are 16.99%, followed by SA/ZnO (13.69%) and free bacteria (7.61%) from 50% concentration slaughter wastewater within 24 h at 37 °C, pH 7.0, and 120 rpm, a significant difference was found between the microsphere and control group. Moreover, when the processing time reaches 36 h, COD degradation of SA/PVA/ZnO microsphere is obviously higher than other groups (SA/PVA/ZnO:SA/ZnO:control vs 18.535 : 15.446: 10.812). Similar results were obtained from 30% concentration slaughter wastewater. Moreover, protein degradation assay was detected, and there are no significant difference (SA/PVA/ZnO:SA/ZnO:control vs 35.4 : 34.4: 36.0). The design of this strategy could greatly enhance the degradation efficiency, inhibit the growth of other bacteria and no effect on the activity of protease in slaughter wastewater. These findings suggested that the nano-ZnO hydrogel immobilization Bacillus velezensis system wastewater treatment is a valuable alternative method for the remediation of pollutants from slaughter wastewater with a novel and eco-friendly with low-cost investment as an advantage.
显示更多 [+] 显示较少 [-]Atmospheric particulate represents a source of C8–C12 perfluoroalkyl carboxylates and 10:2 fluorotelomer alcohol in tree bark
2021
Zhao, Nan | Zhao, Meirong | Liu, Weiping | Jin, Hangbiao
In this study, we analyzed 30 legacy and emerging poly- and perfluoroalkyl substances (PFASs) in paired atmospheric particulate and bark samples collected around a Chinese fluorochemical manufacturing park (FMP), with the aim to explore the sources of PFASs in tree bark. The results showed that PFASs in atmospheric particulate and tree bark samples were consistently dominated by perfluorooctanoate (mean 73 ng/g; 44 pg/m³), perfluorohexanoate (47 ng/g; 36 pg/m³), perfluorononanoate (9.1 ng/g; 8.8 pg/m³), and 10:2 fluorotelomer alcohol (10:2 FTOH; 5.6 ng/g; 12 pg/m³). Spatially, concentrations of C₈–C₁₂ perfluoroalkyl carboxylates (PFCAs) and 10:2 FTOH all showed a similar and exponentially decreased trend in both bark and atmospheric particulate samples with the increasing distance from the FMP. For the first time, we observed strongly significant (Spearman’s correlation coefficient = 0.53–0.79, p < 0.01) correlations between bark and atmospheric particulate concentrations for C₈–C₁₂ PFCAs and 10:2 FTOH over 1–2 orders of magnitude, suggesting that the continues trapping of atmospheric particulates resulted in the accumulation of these compounds in bark. Overall, this study provides the first evidence that atmospheric particulate is an obvious source of C₈–C₁₂ PFCAs and 10:2 FTOH in tree bark. This result may further contribute to the application of tree bark as an indicator of certain PFASs in atmospheric particulate.
显示更多 [+] 显示较少 [-]Structural control of the non-ionic surfactant alcohol ethoxylates (AEOs) on transport in natural soils
2021
Espeso, M Botella | Corada-Fernández, C. | García-Delgado, M. | Candela, L. | González-Mazo, E. | Lara-Martín, P.A. | Jiménez-Martínez, J.
Surfactants, after use, enter the environment through diffuse and point sources such as irrigation with treated and non-treated waste water and urban and industrial wastewater discharges. For the group of non-ionic synthetic surfactant alcohol ethoxylates (AEOs), most of the available information is restricted to the levels and fate in aquatic systems, whereas current knowledge of their behavior in soils is very limited. Here we characterize the behavior of different homologs (C12–C18) and ethoxymers (EO3, EO6, and EO8) of the AEOs through batch experiments and under unsaturated flow conditions during infiltration experiments. Experiments used two different agricultural soils from a region irrigated with reclaimed water (Guadalete River basin, SW Spain). In parallel, water flow and chemical transport were modelled using the HYDRUS-1D software package, calibrated using the infiltration experimental data. Estimates of water flow and reactive transport of all surfactants were in good agreement between infiltration experiments and simulations. The sorption process followed a Freundlich isotherm for most of the target compounds. A systematic comparison between sorption data obtained from batch and infiltration experiments revealed that the sorption coefficient (Kd) was generally lower in infiltration experiments, performed under environmental flow conditions, than in batch experiments in the absence of flow, whereas the exponent (β) did not show significant differences. For the low clay and organic carbon content of the soils used, no clear dependence of Kd on them was observed. Our work thus highlights the need to use reactive transport parameterization inferred under realistic conditions to assess the risk associated with alcohol ethoxylates in subsurface environments.
显示更多 [+] 显示较少 [-]3D printer waste, a new source of nanoplastic pollutants
2020
Rodríguez-Hernández, A.G. | Chiodoni, Angelica | Bocchini, Sergio | Vazquez-Duhalt, Rafael
Plastics pollution has been recognized as a serious environmental problem. Nevertheless, new plastic uses, and applications are still increasing. Among these new applications, three-dimensional resin printers have increased their use and popularity around the world showing a vertiginous annual-sales growth. However, this technology is also the origin of residues generation from the alcohol cleaning procedure at the end of each printing. This alcohol/resin mixture can originate unintentionally very small plastic particles that usually are not correctly disposed, and as consequence, could be easily released to the environment. In this work, the nanoparticle generation from 3D printer’s cleaning procedure and their physicochemical characterization is reported. Nano-sized plastic particles are easily formed when the resin residues are dissolved in alcohol and placed under UV radiation from sunlight. These nanoparticles can agglomerate in seawater showing an average hydrodynamic diameter around 1 μm, whereas the same nanoparticles remain dispersed in ultrapure water, showing a hydrodynamic diameter of ≈300 nm. The formed nanoparticles showed an isoelectric point close to pH 2, which can facilitate their interaction with other positively charged pollutants. Thus, these unexpected plastic nanoparticles can become an environmental issue and public health risk.
显示更多 [+] 显示较少 [-]Biotransformation and tissue bioaccumulation of 8:2 fluorotelomer alcohol in broiler by oral exposure
2020
Chen, Dongmei | Zhao, Ying | Xu, Wei | Pan, Yuanhu | Wei, Qu | Xie, Shuyu
In order to examine whether 8:2 FTOH exposure would lead to a contamination risk of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in broiler derived food, the biotransformation, and tissue distribution and accumulation of 8:2 FTOH following oral exposure in male broilers were investigated. The main metabolites of 8:2 FTOH in plasma and six tissues (muscle, liver, kidney, fat, heart, and lungs) identified by LC-Q-TOF were 2-perfluorooctyl ethanoic acid (8:2 FTCA), 8:2 fluorotelomer unsaturated carboxylic acid (8:2 FTUCA), 3-perfluoroheptyl propanoic acid (7:3 FTCA), perfluoropentanoic acid (PFPeA), perfluorooctanoic acid (PFOA), perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid (PFHxA), perfluorononanoic acid (PFNA), 8:2 FTOH glucuronide conjugate, and 8:2 FTOH sulfate conjugate. The tissue distribution and bioaccumulation of 8:2 FTOH and its unconjugated metabolites were determinated by LC-MS/MS. 8:2 FTOH was quickly depleted in plasma and all six tested tissues, while PFOA, PFNA, and 7:3 FTCA showed strong accumulation in blood and all six examined tissues and were eliminated more slowly than the other metabolites. The tissues with the highest accumulation levels for 8:2 FTOH and its metabolites were heart, kidneys and liver, and the tissue with the lowest accumulation levels was muscle. The elimination half-lifes of PFNA in kidney and 7:3 FTCA in lung were longer compared to those of other metabolites in all six determined tissues. Thus, PFNA and 7:3 FTCA can be selected as potential biomonitoring markers after 8:2 FTOH exposure. This study has improved our understanding of 8:2 FTOH biotransformation and tissue bioaccumulation in broilers, which will help us monitor human exposure risk via food derived from broilers polluted by 8:2 FTOH.
显示更多 [+] 显示较少 [-]Emerging and legacy per- and polyfluoroalkyl substances in water, sediment, and air of the Bohai Sea and its surrounding rivers
2020
Zhao, Zhen | Cheng, Xianghui | Hua, Xia | Jiang, Bin | Tian, Chongguo | Tang, Jianhui | Li, Qilu | Sun, Hongwen | Lin, Tian | Liao, Yuhong | Zhang, Gan
Per- and polyfluoroalkyl substances (PFASs) contamination in the Bohai Sea and its surrounding rivers has attracted considerable attention in recent years. However, few studies have been conducted regarding the distribution of PFASs in multiple environmental media and their distributions between the suspended particles and dissolved phases. In this study, surface water, surface sediment, and air samples were collected at the Bohai Sea to investigate the concentration and distribution of 39 targeted PFASs. Moreover, river water samples from 35 river estuaries were collected to estimate PFAS discharge fluxes to the Bohai Sea. The results showed that total ionic compound (Σi-PFASs) concentrations ranged from 19.3 to 967 ng/L (mean 125 ± 152 ng/L) in the water and 0.70–4.13 ng/g dw (1.78 ± 0.76 ng/g) in surface sediment of the Bohai Sea, respectively. In the estuaries, Σi-PFAS concentrations were ranged from 10.5 to 13500 ng/L (882 ± 2410 ng/L). In the air, ΣPFAS (Σi-PFASs + Σn-PFASs) concentrations ranged from 199 to 678 pg/m³ (462 ± 166 pg/m³). Perfluorooctanoic acid (PFOA) was the predominant compound in the seawater, sediment, and river water; in the air, 8:2 fluorotelomer alcohol was predominant. Xiaoqing River discharged the largest Σi-PFAS flux to the Bohai Sea, which was estimated as 12,100 kg/y. Some alternatives, i.e., 6:2 fluorotelomer sulfonate acid (6:2 FTSA), hexafluoropropylene oxide dimer acid (HFPO-DA), and chlorinated 6:2 polyfluorinated ether sulfonic acid (Cl-6:2 PFESA), showed higher levels than or comparable concentrations to those of the C8 legacy PFASs in some sampling sites. The particle-derived distribution coefficient in seawater was higher than that in the river water. Using high resolution mass spectrometry, 29 nontarget emerging PFASs were found in 3 river water and 3 seawater samples. Further studies should be conducted to clarify the sources and ecotoxicological effects of these emerging PFASs in the Bohai Sea area.
显示更多 [+] 显示较少 [-]Atmospheric concentrations and trends of poly- and perfluoroalkyl substances (PFAS) and volatile methyl siloxanes (VMS) over 7 years of sampling in the Global Atmospheric Passive Sampling (GAPS) network
2018
Rauert, Cassandra | Shoieb, Mahiba | Schuster, Jasmin K. | Eng, Anita | Harner, Tom
Poly- and per-fluoroalkyl substances (PFAS) and volatile methyl siloxanes (VMS) were monitored at 21 sites in the Global Atmospheric Passive Sampling (GAPS) Network. Atmospheric concentrations previously reported from 2009 were compared to concentrations measured at these sites in 2013 and 2015, to assess trends over 7 years of monitoring. Concentrations of the fluorotelomer alcohols (FTOHs) and fluorinated sulfonamides and sulfonamidoethanols (FOSAs and FOSEs) were stable at these sites from 2009 to 2015 with no significant difference (p > 0.05) in concentrations. Elevated concentrations of all the neutral PFAS were detected at the urban sites as compared to the polar/background sites. The perfluorosulfonic acids (PFSAs), meanwhile, saw a significant increase (p < 0.001) in concentrations from 2009 to 2015. The perfluorocarboxylic acids (PFCAs) had elevated concentrations in 2015, however, the difference was not statistically significant (p > 0.05). Concentrations of the PFSAs and the PFCAs were similar at all location types, showing the global reach of these persistent compounds. Concentrations of the cyclic VMS (cVMS) were at least an order of magnitude higher than the linear VMS (lVMS) and the PFAS. Octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) saw a weak significant increase in concentrations from 2009 to 2013 (p < 0.05), however, hexamethylcyclotrisiloxane (D3) had a strong significant decrease in concentrations from 2009 to 2015 (p < 0.01).
显示更多 [+] 显示较少 [-]Fluorotelomer alcohols (FTOHs), brominated flame retardants (BFRs), organophosphorus flame retardants (OPFRs) and cyclic volatile methylsiloxanes (cVMSs) in indoor air from occupational and home environments
2018
Sha, Bo | Dahlberg, Anna-Karin | Wiberg, Karin | Ahrens, Lutz
Indoor air samples were collected from private homes and various occupational indoor environments using passive air sampler and analysed for fluorotelomer alcohols (FTOHs), brominated flame retardants (BFRs), organophosphorus flame retardants (OPFRs) and cyclic volatile methyl siloxanes (cVMSs). The aim was to investigate their occurrence in indoor air, factors that may affect their presence and human daily exposure dose (DED) via inhalation. In general, levels of cVMSs were 3–4 orders of magnitude greater than the other compound classes. OPFRs concentration was found significantly higher than BFRs in indoor air. The most abundant compounds in each chemical class were 8:2 FTOH, 2,4,6-TBP, TNBP and TCEP and decamethylcyclopentasiloxane (D5). Home samples contained higher level of FTOHs, BFRs and cVMSs than occupational environments, whereas concentration of OPFRs in office samples were higher. BFRs concentrations were significantly correlated with building age and with the number of electronic/electrical devices at the sampling sites. Moreover, significantly lower levels of FTOHs and cVMSs were observed in rooms with forced-ventilation system. Estimated DED via inhalation was significantly higher at home than in office and the total DED was on average 3–5 orders of magnitude lower than the reference value.
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