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A sustainable Decision Support System for soil bioremediation of toluene incorporating UN sustainable development goals Полный текст
2022
Akbarian, Hadi | Jalali, Farhad Mahmoudi | Gheibi, Mohammad | Hajiaghaei-Keshteli, Mostafa | Akrami, Mehran | Sarmah, Ajit K.
Decision Support System (DSS) is a novel approach for smart, sustainable controlling of environmental phenomena and purification processes. Toluene is one of the most widely used petroleum products, which adversely impacts on human health. In this study, Fusarium Solani fungi are utilized as the engine of the toluene bioremediation procedure for the monitoring part of DSS. Experiments are optimized by Central Composite Design (CCD) - Response Surface Methodology (RSM), and the behavior of the mentioned fungi is estimated by M5 Pruned model tree (M5P), Gaussian Processes (GP), and Sequential Minimal Optimization (SMOreg) algorithms as the prediction section of DSS. Finally, the control stage of DSS is provided by integrated Petri Net modeling and Failure Modes and Effects Analysis (FMEA). The findings showed that Aeration Intensity (AI) and Fungi load/Biological Waste (F/BW) are the most influential mechanical and biological factors, with P-value of 0.0001 and 0.0003, respectively. Likewise, the optimal values of main mechanical parameters include AI, and the space between pipes (S) are equal to 13.76 m³/h and 15.99 cm, respectively. Also, the optimum conditions of biological features containing F/BW and pH are 0.001 mg/g and 7.56. In accordance with the kinetic study, bioremediation of toluene by Fusarium Solani is done based on a first-order reaction with a 0.034 s-1 kinetic coefficient. Finally, the machine learning practices showed that the GP (R2 = 0.98) and M5P (R2 = 0.94) have the most precision for predicting Removal Percentage (RP) for mechanical and biological factors, respectively. At the end of the present research, it is found that by controlling seven possible risk factors in bioremediation operation through the FMEA- Petri Net technique, efficiency of the process can be adjusted to optimum value.
Показать больше [+] Меньше [-]Elemental composition of fine and coarse particles across the greater Los Angeles area: Spatial variation and contributing sources Полный текст
2022
Oroumiyeh, Farzan | Jerrett, Michael | Del Rosario, Irish | Lipsitt, Jonah | Liu, Jonathan | Paulson, Suzanne E. | Ritz, Beate | Schauer, James J. | Shafer, Martin M. | Shen, Jiaqi | Weichenthal, Scott | Banerjee, Sudipto | Zhu, Yifang
The inorganic components of particulate matter (PM), especially transition metals, have been shown to contribute to PM toxicity. In this study, the spatial distribution of PM elements and their potential sources in the Greater Los Angeles area were studied. The mass concentration and detailed elemental composition of fine (PM₂.₅) and coarse (PM₂.₅₋₁₀) particles were assessed at 46 locations, including urban traffic, urban community, urban background, and desert locations. Crustal enrichment factors (EFs), roadside enrichments (REs), and bivariate correlation analysis revealed that Ba, Cr, Cu, Mo, Pd, Sb, Zn, and Zr were associated with traffic emissions in both PM₂.₅ and PM₂.₅₋₁₀, while Fe, Li, Mn, and Ti were affected by traffic emissions mostly in PM₂.₅. The concentrations of Ba, Cu, Mo, Sb, Zr (brake wear tracers), Pd (tailpipe tracer), and Zn (associated with tire wear) were higher at urban traffic sites than urban background locations by factors of 2.6–4.6. Both PM₂.₅ and PM₂.₅₋₁₀ elements showed large spatial variations, indicating the presence of diverse emission sources across sampling locations. Principal component analysis extracted four source factors that explained 88% of the variance in the PM₂.₅ elemental concentrations, and three sources that explained 86% of the variance in the PM₂.₅₋₁₀ elemental concentrations. Based on multiple linear regression analysis, the contribution of traffic emissions (27%) to PM₂.₅ was found to be higher than mineral dust (23%), marine aerosol (18%), and industrial emissions (8%). On the other hand, mineral dust was the dominant source of PM₂.₅₋₁₀ with 45% contribution, followed by marine aerosol (22%), and traffic emissions (19%). This study provides novel insight into the spatial variation of traffic-related elements in a large metropolitan area.
Показать больше [+] Меньше [-]Restriction of biosolids returning to land: Fate of antibiotic resistance genes in soils after long-term biosolids application Полный текст
2022
Qin, Xuechao | Zhai, Limei | Khoshnevisan, Benyamin | Pan, Junting | Liu, Hongbin
Although the utilization of biosolids in agricultural lands is widely considered as an effective way to improve resource reuse, the presence of antibiotic resistance genes (ARGs) severely restricts biosolids returning to fields. A 12-year long-term experiment with different biosolids application rates (from 0 to 36 t ha⁻¹ yr⁻¹) was conducted to study the effect of biosolids application on shaping ARGs in soil. Biosolids application significantly increased ARGs abundance in the soil, except for MBS treatment (9 t ha⁻¹ yr⁻¹ biosolids application). The abundance of ARGs in soil did not increase linearly with the dose of biosolids applied, but they were significantly (P < 0.05) positively correlated. A total of 173 subtypes were detected, among them mobile genetic elements (MGEs), aminoglycoside, and multidrug resistance genes were the most dominant types. Except for MBS treatment, most of the ARGs detected were enriched in amended soils after long-term continuous biosolids application. Specifically, tetPA, sul1, mefA, and IS6100 were highly enriched in all amended soils. In addition, biosolids application increased soil nutrients and heavy metals, and changed the soil microbial community, all of which affected ARGs formation. But MGEs may be a greater factor for shaping ARGs profiles than soil properties. Overall, controlling the rate of biosolid application is the key to reducing the accumulation and horizontal transfer of ARGs in soils.
Показать больше [+] Меньше [-]Responses of reconstituted human bronchial epithelia from normal and health-compromised donors to non-volatile particulate matter emissions from an aircraft turbofan engine Полный текст
2022
Delaval, Mathilde N. | Jonsdottir, Hulda R. | Leni, Zaira | Keller, Alejandro | Brem, Benjamin T. | Siegerist, Frithjof | Schönenberger, David | Durdina, Lukas | Elser, Miriam | Salathe, Matthias | Baumlin, Nathalie | Lobo, Prem | Burtscher, Heinz | Liati, Anthi | Geiser, Marianne
Health effects of particulate matter (PM) from aircraft engines have not been adequately studied since controlled laboratory studies reflecting realistic conditions regarding aerosols, target tissue, particle exposure and deposited particle dose are logistically challenging. Due to the important contributions of aircraft engine emissions to air pollution, we employed a unique experimental setup to deposit exhaust particles directly from an aircraft engine onto reconstituted human bronchial epithelia (HBE) at air-liquid interface under conditions similar to in vivo airways to mimic realistic human exposure. The toxicity of non-volatile PM (nvPM) from a CFM56-7B26 aircraft engine was evaluated under realistic engine conditions by sampling and exposing HBE derived from donors of normal and compromised health status to exhaust for 1 h followed by biomarker analysis 24 h post exposure. Particle deposition varied depending on the engine thrust levels with 85% thrust producing the highest nvPM mass and number emissions with estimated surface deposition of 3.17 × 10⁹ particles cm⁻² or 337.1 ng cm⁻². Transient increase in cytotoxicity was observed after exposure to nvPM in epithelia derived from a normal donor as well as a decrease in the secretion of interleukin 6 and monocyte chemotactic protein 1. Non-replicated multiple exposures of epithelia derived from a normal donor to nvPM primarily led to a pro-inflammatory response, while both cytotoxicity and oxidative stress induction remained unaffected. This raises concerns for the long-term implications of aircraft nvPM for human pulmonary health, especially in occupational settings.
Показать больше [+] Меньше [-]Sodium alginate/magnetic hydrogel microspheres from sugarcane bagasse for removal of sulfamethoxazole from sewage water: Batch and column modeling Полный текст
2022
Prasannamedha, G. | Kumar, P Senthil | Shivaani, S. | Kokila, M.
Magnetic carbon were synthesized from sugarcane bagasse using hydrothermal carbonization followed by thermal activation was converted to solid state as beads (hydrogels SACFe) using sodium alginate and applied as adsorbent in removal sulfamethoxazole in batch and column mode. From adsorption parameter analysis it was confirmed that 0.6 g L⁻¹ SACFe was effective in removing 50 mg L⁻¹ of SMX at pH 6.2. Sorption of SMX on SACFe beads followed Elovich kinetics and Freundlich isotherm. It was further confirmed that sorption occurred on heterogeneous surface of SACFe beads with chemisorption as rate limiting step. Maximum adsorption capacity was obtained as 58.439 mg g⁻¹ pH studies revealed that charged assisted hydrogen bonding, EDA interactions are some of the mechanism that favoured removal of SMX. From column studies it was found that bead height of 2 cm and flow rate of 1.5 mL min⁻¹ found to be best in removing pollutant. Thomas model fitted better the experimental data stating that improved interaction between adsorbent and adsorbate act as major driving force tool in obtaining maximum sorption capacity. Breakthrough curve was completely affected by varied flow rate and bed height. Column adsorption was effective in reducing COD and BOD levels of sewage which are affected by toxic pollutants and miscellaneous compounds. Feasibility analysis showed that SACFe beads could be employed for real-time applications as it is cost, energy effective and easy recovery.
Показать больше [+] Меньше [-]Functional group diversity for the adsorption of lead(Pb) to bacterial cells and extracellular polymeric substances Полный текст
2022
Qu, Chenchen | Yang, Shanshan | Mortimer, Monika | Zhang, Ming | Chen, Jinzhao | Wu, Yichao | Chen, Wenli | Cai, Peng | Huang, Qiaoyun
Bacteria and their secreted extracellular polymeric substances (EPS) are widely distributed in ecosystems and have high capacity for heavy metal immobilization. The knowledge about the molecular-level interactions with heavy metal ions is essential for predicting the behavior of heavy metals in natural and engineering systems. This comprehensive study using potentiometric titration, Fourier-transform infrared (FTIR) spectroscopy, isothermal titration calorimetry (ITC) and X-ray absorption fine structure (XAFS) was able to reveal the functional diversity and adsorption mechanisms for Pb onto bacteira and the EPS in greater detail than ever before. We identified mono-carboxylic, multi-carboxylic, phosphodiester, phosphonic and sulfhydryl sites and found the partitioning of Pb to these functional groups varied between gram-negative and gram-positive bacterial strains, the soluble and cell-bound EPS and Pb concentrations. The sulfhydryl and phosphodiester groups preferentially complexed with Pb in P. putida cells, while multifunctional carboxylic groups promoted Pb adsorption in B. subtilis cells and the protein fractions in EPS. Though the functional site diversity, the adsorption of Pb to organic ligands occurred spontaneously through a universal entropy increase and inner-sphere complexation mechanism. The functional group scale knowledge have implications for the modeling of heavy metal behavior in the environment and application of these biological resources.
Показать больше [+] Меньше [-]Simultaneous removal of arsenic and toxic metals from contaminated soil: Laboratory development and pilot scale demonstration Полный текст
2022
Morales Arteaga, Juan Francisco | Gluhar, Simon | Kaurin, Anela | Lestan, Domen
Soil chemistry of toxic metalloids and metals differs, making their simultaneous removal difficult. Soil contaminated with As, Pb, Zn and Cd was washed with oxalic acid, Na-dithionite and EDTA solution. Toxic elements were removed from the washing solution by alkalinisation with CaO to a pH 12.5: As was co-precipitated with Fe from Fe-EDTA chelate formed after the soil washing. The toxic metals precipitated after substitution of their EDTA chelates with Ca. The novel method was scaled up on the ReSoil® platform. On average, 60, 76, 29, and 53% of As, Pb, Zn, and Cd were removed, no wastewater was generated and EDTA was recycled. Addition of zero-valent iron reduced the toxic elements’ leachability. Remediation was most effective for As: phytoaccessibility (CaCl₂ extraction), mobility (NH₄NO₃), and accessibility from human gastric and gastrointestinal phases were reduced 22, 104, 6, and 51 times, respectively. Remediation increased pH but had no effect on soil functioning assessed by fluorescein diacetate hydrolysis, dehydrogenase, β-glucosidase, urease, acid and alkaline phosphatase activities. Brassica napus produced 1.9 times more biomass on remediated soil, accumulated no As and 5.0, 2.6, and 9.0 times less Pb, Zn and Cd, respectively. We demonstrated the novel remediation technology as cost-efficient (material cost = 41.86 € t⁻¹) and sustainable.
Показать больше [+] Меньше [-]Effects of shrimp pond effluent on functional traits and functional diversity of mangroves in Zhangjiang Estuary Полный текст
2022
Gao, Chang-Hao | Zhang, Shan | Wei, Ming-Yue | Ding, Qian-Su | Ma, Dong-Na | Li, Jing | Wen, Chen | Li, Huan | Zhao, Zhi-Zhu | Wang, Junhui | Zheng, Hai-Lei
In recent years, the scale of shrimp ponds has rapidly increased adjacent to mangrove forests. Discharge of shrimp pond effluent has led to degradation of the surrounding environment and reduction of biodiversity in the estuary. But it remains poorly understood how shrimp pond effluent affects functional traits and functional diversity of mangroves. We sampled roots, stems and leaves of Kandelia obovata and other mangrove plants, as well as sediments and pore water from shrimp pond effluent polluted area (P) and clean area (control area, C) in Zhangjiang Estuary in southeast coast of China. Twenty plant functional traits and six functional diversity indices were analyzed to explore the effects of shrimp pond effluent on individual plants and mangrove communities. The results showed that the discharge of shrimp pond effluent significantly affected the nutrient content in soils and pore water, for example, sediment NH₄⁺ and NO₃⁻ concentration increased from 0.26 ± 0.06 to 0.77 ± 0.29 mg/g and from 0.05 ± 0.03 to 0.16 ± 0.05 mg/g, respectively, when comparing the C and P site. Furthermore, some mangrove plant functional traits such as plant height, diameter at breast height, canopy thickness and specific leaf area were significantly increased by the effluent discharge. Functional diversity in the polluted area reduced as a whole compared to the control area. In particular, ammonium and nitrate nitrogen input is the main reason to induce the changes of plant functional traits and functional diversity. Besides, the community structure changed from functional differentiation to functional convergence after shrimp pond effluent discharge. In addition, the long-term shrimp pond effluent discharge may lead to the ecological strategy shift of K. obovata, while different organs may adopt different ways of nutrient uptake and growth strategies in the face of effluent disturbance. In conclusion, pollution from shrimp pond does affect the functional traits of mangrove plants and functional diversity of mangrove community. These results provide strong evidence to assess the impact of effluent discharges on mangrove plants and provide theoretical basis for conservation and sustainable development of mangroves.
Показать больше [+] Меньше [-]The relationship between particulate matter and lung function of children: A systematic review and meta-analysis Полный текст
2022
Zhang, Wenjing | Ma, Runmei | Wang, Yanwen | Jiang, Ning | Zhang, Yi | Li, Tiantian
There have been many studies on the relationship between fine particulate matter (PM₂.₅) and lung function. However, the impact of short-term or long-term PM₂.₅ exposures on lung function in children is still inconsistent globally, and the reasons for the inconsistency of the research results are not clear. Therefore, we searched the PubMed, Embase and Web of Science databases up to May 2022, and a total of 653 studies about PM₂.₅ exposures on children's lung function were identified. Random effects meta-analysis was used to estimate the combined effects of the 25 articles included. PM₂.₅ concentrations in short-term exposure studies mainly come from individual and site monitoring. And for every 10 μg/m³ increase, forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁) and peak expiratory flow (PEF) decreased by 21.39 ml (95% CI: 13.87, 28.92), 25.66 ml (95% CI: 14.85, 36.47) and 1.76 L/min (95% CI: 1.04, 2.49), respectively. The effect of PM₂.₅ on lung function has a lag effect. For every 10 μg/m³ increase in the 1-day moving average PM₂.₅ concentration, FEV₁, FVC and PEF decreased by 14.81 ml, 15.40 ml and 1.18 L/min, respectively. PM₂.₅ concentrations in long-term exposure studies mainly obtained via ground monitoring stations. And for every 10 μg/m³ increase, FEV₁, FVC and PEF decreased by 61.00 ml (95% CI: 25.80, 96.21), 54.47 ml (95% CI: 7.29, 101.64) and 10.02 L/min (95% CI: 7.07, 12.98), respectively. The sex, body mass index (BMI), relative humidity (RH), temperature (Temp) and the average PM₂.₅ exposure level modify the relationship between short-term PM₂.₅ exposure and lung function. Our study provides further scientific evidence for the deleterious effects of PM₂.₅ exposures on children's lung function, suggesting that exposure to PM₂.₅ is detrimental to children's respiratory health. Appropriate protective measures should be taken to reduce the adverse impact of air pollution on children's health.
Показать больше [+] Меньше [-]Exploiting urban roadside snowbanks as passive samplers of organic micropollutants and metals generated by traffic Полный текст
2022
Müller, Alexandra | Österlund, Heléne | Maršálek, Jiři | Viklander, M.
Stormwater and snowmelt runoff is known to contribute to the deterioration of quality of urban surface waters. Vehicular traffic is recognised as a major source of a wide range of pollutants to urban runoff, including conventional pollutants, such as suspended solids and metals, and those referred to as ‘contaminants of emerging concern’. The aim of this study was to investigate the contribution of selected metal(loid)s (Cd, Cr, Cu, Ni, Pb, Pd, Sb, W, Zn), polycyclic aromatic hydrocarbons (PAHs), nonylphenols, octylphenols and –ethoxylates, phthalates and bisphenol A (BPA) from vehicular traffic by sampling urban roadside snow at eight sites, with varying traffic intensities, and one control site without direct impacts of traffic. Our results confirmed that vehicles and traffic-related activities were the sources of octylphenols, BPA and phthalates as well as the metal(loid)s Sb and W, infrequently reported in previous studies. Among metal(loid)s, Cu, Zn and W occurred in the highest concentrations (up to 1.2 mg/L Cu, 2.4 mg/L Zn and 1.9 mg/L W), while PAHs and phthalates occurred in the highest concentrations among the trace organic pollutants (up to 540 μg/L phthalate diisononyl phthalate). Among the phthalates, di-(2-ethylhexyl)phthalate had the highest frequency of detection (43% of the roadside samples). While BPA and octylphenols had relatively high frequencies of detection (50% for BPA and 81% for octylphenols), they were present in comparatively low concentrations (up to 0.2 μg/L BPA and 1.1 μg/L octylphenols). The control site displayed generally low concentrations of the pollutants studied, indicating that atmospheric deposition was not a significant source of the pollutants found in the roadside snow. Several of the pollutants in the roadside snow exceeded the applicable surface water and stormwater effluent guideline values. Thus, the transport of these pollutants with runoff posed risk of causing adverse effects in the receiving surface waters.
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