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Natural additives contribute to hydrocarbon and heavy metal co-contaminated soil remediation
2022
Cavazzoli, Simone | Selonen, Ville | Rantalainen, Anna-Lea | Sinkkonen, Aki | Romantschuk, Martin | Squartini, Andrea
A biological treatment method was tested in laboratory conditions for the removal of hydrocarbons contained in a waste disposal soil sample consisting of excavated sandy soil from a former fueling station. Two fractions of hydrocarbons were quantified by GC-FID: diesel (C₁₀–C₂₁) and lubricant oil (C₂₂–C₄₀). Meat and bone meal (MBM, 1% w/w) was used as a bio-stimulant agent for soil organisms. Cyclodextrin, an oligosaccharide produced from starch by enzymatic conversion, was also used to assess its ability to improve the bioavailability/biodegradability of hydrocarbons in the soil. Parameters such as temperature, pH, water content and aeration (O₂ availability) were monitored and optimized to favor degradation processes. Two different experimental tests were prepared: one to measure the degradation of hydrocarbons; the other to monitor the mobility of some elements in the soil and in the leachate produced by watering with tap water. Soil samples treated with MBM and cyclodextrin showed, over time, a greater removal of the more persistent hydrocarbon fraction (lubricant oil). MBM-treated soils underwent a faster hydrocarbon removal kinetic, especially in the first treatment period. However, the final hydrocarbon concentrations are comparable in all treatments, including control. Over time, the effect of cyclodextrin on hydrocarbon degradation seemed to be relevant. MBM-treated soils sequestered lead in the very first weeks. These results highlight the intrinsic capacity of soil, and its indigenous microbial communities, to degrade petroleum hydrocarbons and suggest that MBM-induced bioremediation is a promising, environmentally friendly technology which should be considered when dealing with hydrocarbon/heavy metal co-contaminated soils.
Afficher plus [+] Moins [-]A sustainable Decision Support System for soil bioremediation of toluene incorporating UN sustainable development goals
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.
Afficher plus [+] Moins [-]Responses of reconstituted human bronchial epithelia from normal and health-compromised donors to non-volatile particulate matter emissions from an aircraft turbofan engine
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.
Afficher plus [+] Moins [-]Sodium alginate/magnetic hydrogel microspheres from sugarcane bagasse for removal of sulfamethoxazole from sewage water: Batch and column modeling
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.
Afficher plus [+] Moins [-]Mapping agricultural use of pesticides to enable research and environmental health actions in Belgium
2022
Habran, Sarah | Philippart, Christelle | Jacquemin, Pierre | Remy, Suzanne
Given the many public health and environmental impacts associated with the use of pesticides, comprehensive pesticide application data are a high priority for environmental and health professionals, government agencies, and community groups in Wallonia (Belgium). In that context, geographic information system (GIS) approaches for mapping estimates of agricultural pesticide use were developed in the present study. Data on pesticide application rates and high-resolution annual datasets of the geographic distribution of crops were used to complete this analysis in Wallonia over the period 2015–2017. The method was implemented in Python in order to allow easy update and improvements of maps, or to segment maps by individual pesticides, chemical groups of pesticides (e.g. insecticides, herbicides), etc. Linked databases were created to classify, select, and possibly weight AIs according to specific requests and criteria. The results provide a first map of agricultural pesticide use in Wallonia, which depicts the best picture up to now of their geographic distribution. Maps of fungicides, herbicides, and plant growth regulators showed quite similar spatial patterns as the map of the combination of all pesticides. In contrast, the insecticide map showed a specific pattern related almost exclusively to dwarf-tree orchards in some municipalities in northern Wallonia. This research work is a preliminary result on the spatial characterization of agricultural pesticide use in Wallonia and give a valuable basis for research and environmental health actions in Belgium. Forthcoming developments will focus on exposure characterization to agricultural pesticides using GIS models. Using this information, policymakers will able to detect potential priority zones and take action to check and reduce agricultural pesticide loads in the environment.
Afficher plus [+] Moins [-]Anthocyanin-mediated arsenic tolerance in plants
2022
Ahammed, Golam Jalal | Yang, Youxin
Plants detoxify toxic metal(loid)s by accumulating diverse metabolites. Beside scavenging excess reactive oxygen species (ROS) induced by metal(loid)s, some metabolites chelate metal(loid) ions. Classically, thiol-containing compounds, especially glutathione (GSH) and phytochelatins (PCs) are thought to be the major chelators that conjugate with metal(loid)s in the cytoplasm followed by transport and sequestration in the vacuole. In addition to this classical detoxification pathway, a role for secondary metabolites in metal(loid) detoxification has recently emerged. In particular, anthocyanins, a kind of flavonoids with ROS scavenging potential, contribute to enhanced arsenic tolerance in several plant species. Evidence is accumulating that, in analogy to GSH and PCs, anthocyanins may conjugate with arsenic followed by vacuolar sequestration in the detoxification event. Exogenous application or endogenous accumulation of anthocyanins enhances arsenic tolerance, leading to improved plant growth and productivity. The application of some plant hormones and signaling molecules stimulates endogenous anthocyanin synthesis which confers tolerance to arsenic stress. Anthocyanin biosynthesis is transcriptionally regulated by several transcription factors, including myeloblastosis (MYBs). The light-regulated transcription factor elongated hypocotyl 5 (HY5) also affects anthocyanin biosynthesis, but its role in arsenic tolerance remains elusive. Here, we review the mechanism of arsenic detoxification in plants and the potential role of anthocyanins in arsenic tolerance beyond the classical points of view. Our analysis proposes that anthocyanin manipulation in crop plants may ensure sustainable crop yield and food safety in the marginal lands prone to arsenic pollution.
Afficher plus [+] Moins [-]Nitrogen concentration response to the decline in atmospheric nitrogen deposition in a hypereutrophic lake
2022
Jiang, Xingyu | Gao, Guang | Deng, Jianming | Zhu, Guangwei | Tang, Xiangming | Shao, Keqiang | Hu, Yang
Atmospheric nitrogen (N) deposition is becoming an increasingly important factor affecting the nutrient level of lakes, especially considering the long-term control measures for external N inputs in developed regions. However, few studies have investigated the effects of atmospheric N deposition and the respective ecological significance in eutrophic waters. In this study, bulk and wet deposition rates of all N species and water N concentrations in Lake Taihu were determined based on the long-term (2010–2018) high-resolution (weekly or monthly) systematic observations. The results indicated that the decline in wind speed and change in land-use type likely decreased the N deposition rate. The bulk N deposition rates decreased from 45.77 kg N ha⁻¹ yr⁻¹ in 2012 to 22.06 kg N ha⁻¹ yr⁻¹ in 2018, which could account for decrease of 1.01 mg N L⁻¹ in the lake N concentrations via a rough estimation, and this value was close to the actual variation in N concentration in Lake Taihu. The correlation between N concentrations and atmospheric deposition fluxes was stronger than that between N concentrations and riverine N inputs or lake storage, which further indicated that change in atmospheric N deposition was the key reason for the variation in N concentrations. The direct bulk N deposition into Lake Taihu accounted for 17.5% and 51.4% of the riverine N inputs and lake N inventory, respectively. Moreover, atmospheric N deposition was concentrated in summer, which was dominated by reduced N, and it may be important for the duration of algal blooms. Therefore, external N inputs, including atmospheric N deposition, should be further controlled for an effective mitigation of eutrophication and algal blooms in Lake Taihu.
Afficher plus [+] Moins [-]The bisphenol A metabolite MBP causes proteome alterations in male Cyprinodon variegatus fish characteristic of estrogenic endocrine disruption
2022
Schönemann, Alexandre M. | Moreno Abril, Sandra Isabel | Diz, Angel P. | Beiras, Ricardo
The toxicological status of bisphenol A (BPA) is under strong debate. Whereas in vitro it is an agonist of the estrogen receptor with a potency ca. 10⁵-fold lower than the natural female hormone estradiol, in vivo exposure causes only mild effects at concentration thresholds environmentally not relevant and inconsistent among species. By using a proteomic approach, shotgun liver proteome analysis, we show that 7-d exposure to 10 μg/L of the BPA metabolite, 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP), and not the same exposure to the parental molecule BPA, alters the liver proteome of male Cyprinodon variegatus fish. Different physiological and environmental conditions leading to biotransformation of BPA to MBP may partly explain the conflicting results so far reported for in vivo BPA exposures. The pattern of alteration induced by MBP is similar to that caused by estradiol, and indicative of estrogenic endocrine disruption. MBP enhanced ribosomal activity, protein synthesis and transport, with upregulation of 91% of the ribosome-related proteins, and 12 proteins whose expression is regulated by estrogen-responsive elements, including vitellogenin and zona pellucida. Whey acidic protein (WAP) was the protein most affected by MBP exposure (FC = 68). This result points at WAP as novel biomarker for xenoestrogens.
Afficher plus [+] Moins [-]Promotion of the biodegradation of phenanthrene adsorbed on microplastics by the functional bacterial consortium QY1 in the presence of humic acid: Bioavailability and toxicity evaluation
2022
Zhu, Minghan | Yin, Hua | Yuan, Yibo | Qi, Xin | Liu, Hang | Wei, Xipeng | Luo, Haoyu | Dang, Zhi
The adsorption of hydrophobic organic compounds (HOCs) by microplastics (MPs) has attracted great attention in recent years. However, the ultimate environmental fate of the HOCs sorbed on MPs (HOCs-MPs) is poorly understood. In this work, we investigated the potential influence of the biotransformation process on the environmental fate of phenanthrene (PHE, a model HOC) sorbed on MPs (PHE-MPs) under the existence of humic acid (HA, the main ingredient of dissolved organic matter (DOM)) in the aquatic environment. The results indicated that the adsorption behavior of PHE on MPs decreased its bioavailability and thus inhibited its biotransformation efficiency. However, HA significantly promoted the biodegradation rate and percentage of PHE-MPs. This was probably because HA improved the desorption of PHE from MPs, which promoted the acquisition of PHE by bacteria from the aqueous phase. Further, HA dramatically increased the bacterial community diversity and richness and altered the community composition. The richness of some PHE-degrading bacteria, such as Methylobacillus and Sphingomonas, significantly increased, which may also be an important factor for promoting PHE biodegradation. Molecular ecological network analysis implied that HA enhanced the modularity and complexity of bacterial interaction networks, which was beneficial to maintaining the functional stability of the consortium QY1. Besides, HA decreased the cytotoxicity of functional microbes induced by HOCs-MPs. This work broadens our knowledge of the environmental fate of HOCs-MPs and interactions of MPs, HOCs, DOMs and functional microbial consortiums in aqueous environments.
Afficher plus [+] Moins [-]Temporal and spatial variations in nitrogen use efficiency of crop production in China
2022
Yan, Xiaoyuan | Xia, Longlong | Ti, Chaopu
The low value of nitrogen use efficiency (NUE) (around 30%) of crop production in China highlights the necessity to adopt reasonable N managements in national scale. After the implementation of ‘National Soil Testing and Formulated Fertilization’ program in 2005, many field experiments have reported an increase of NUE for crop productions in China. This has prompted discussion regarding the extent to which NUE in crop production has been improved. Here, we analyzed the temporal and spatial changes in NUE (crop N uptake/total N input) and cumulative synthetic and non-synthetic N fertilizer recovery efficiency of crop production in China during 1980–2014, and evaluated the relationship between NUE and economic growth (purchasing power parity, PPP) at national and provincial scale. The results showed that the overall NUE of crop production in China clearly increased from 35 to 42% during 2003–2014, and an increase in NUE was further evidenced by increases in cumulative recovery efficiency of both synthetic and non-synthetic N fertilizer. The relationship between NUE and PPP can be described by an environmental Kuznets curve at the national scale, with NUE first decreasing then increasing with PPP. However, this relationship exhibited large spatial variation: 1) In economically developed (e.g., Guangdong and Zhejiang) and undeveloped provinces (e.g., Yunnan and Guizhou), NUE generally decreased and then remained at low levels (20–35%) as PPP increased. 2) In major agricultural provinces with high (e.g., Shandong and Jiangsu) or intermediate levels (e.g., Hunan and Hebei) of economic development, a pronounced increasing trend in NUE with PPP was observed. These results highlight the necessity of developing region-oriented N management strategies to further increase the NUE of crop production in China, particularly in the economically developed and undeveloped provinces.
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