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Contaminated soils of different natural pH and industrial origin: The role of (nano) iron- and manganese-based amendments in As, Sb, Pb, and Zn leachability Full text
2021
Hiller, Edgar | Jurkovič, Ľubomír | Faragó, Tomáš | Vítková, Martina | Tóth, Roman | Komárek, Michael
Soils containing a large proportion of industrial waste can pose a health risk due to high environmentally available concentrations of toxic metal(loid)s. Nano zero-valent iron (nZVI) and amorphous manganese oxide (AMO) were applied as immobilising amendments (1 wt%) to soils with different industrial origin of As and Sb, and leaching of As, Sb, Pb, and Zn was investigated using a single extraction with deionised water. The different industrial impact was reflected in the mineralogy, chemical composition and pH of these soils. Water-soluble As ratios positively correlated with pH in all experimental treatments. A significant decrease of water-soluble As ratios was observed in all nZVI-amended soils (~65–93% of the control) except for one sample with the lowest solution pH. Nano zero-valent iron was also successful in Sb immobilisation (~76–90% of the control). Highly variable results were obtained for AMO, which only led to a decrease of water-soluble As in soils with solution pH of ≥7 (~70–80% of the control), probably due to lower stability of AMO in acidic conditions. In each case, nZVI was more efficient at decreasing water-soluble As ratios than AMO. Dissolved Pb concentrations remained unchanged after the application of nZVI and AMO, and the decrease of Zn leaching using AMO was controlled mainly by soil pH increase induced by its application. According to the calculated saturation indices, tripuhyite (FeSbO₄) was predicted to be the key mineral controlling Sb solubility in mine soils. Secondary Fe (hydr)oxides either originally present or newly formed due to nZVI oxidation were instrumentally identified at different stages of their transformation and metal(loid) retention. To conclude, nZVI is suitable for application to contaminated soils at a wide pH range, while the use of AMO for decreasing As leaching is limited to soils with pH ≥ 7.
Show more [+] Less [-]Black carbon deposited in Hariqin Glacier of the Central Tibetan Plateau record changes in the emission from Eurasia Full text
2021
Wang, Mo. | Xu, Baiqing | Wang, Hailong | Zhang, Rudong | Yang, Yang | Gao, Shaopeng | Tang, Xiangxiang | Wang, Ninglian
Black carbon (BC), by the combustion of fossil fuels and biomass, has profound effects on climate change and glacier retreat in industrial eras. In the present study, we report refractory BC (rBC) in an ice core spanning 1850–2014, retrieved from the Hariqin Glacier of the Tanggula Mountains in the central Tibetan Plateau, measured using a single particle soot photometer (SP2). The rBC concentration shows a three-fold increase since the 1950s. The mean rBC concentration was 0.71 ± 0.52 ng mL⁻¹ during 1850s–1940s and 2.11 ± 1.60 ng mL⁻¹ during 1950s–2010s. The substantial increase in rBC since the 1950s is consistent with rBC ice core records from the Tibetan Plateau and Eastern Europe. According to the predominant atmospheric circulation patterns over the glacier and timing of changes in regional emissions, the post-1950 amplification of rBC concentration in the central Tibetan Plateau most likely reflects increases in emissions in Eastern Europe, former USSR, the Middle East, and South Asia. Despite the low-level background rBC concentrations in the ice cores from the Tibetan Plateau, the present study highlights a remarkable increase in anthropogenic BC emissions in recent decades and the consequent influence on glaciers in the Tibetan Plateau.
Show more [+] Less [-]RETRACTED: Cytotoxicity and genotoxicity evaluation of polystyrene microplastics on Vicia faba roots Full text
2021
Lu, Yin | Ma, Qin | Xu, Xiaolu | Yu, Zhefu | Guo, Tianjiao | Wu, Yangkai
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors and Corresponding Author.The authors have plagiarized part of a paper that had already appeared in Environmental and Experimental Botany, 179 (2020) 104227, https://doi.org/10.1016/j.envexpbot.2020.104227. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
Show more [+] Less [-]Life cycle sustainability assessment of the nanoscale zero-valent iron synthesis process for application in contaminated site remediation Full text
2021
Visentin, Caroline | Trentin, Adan William da Silva | Braun, Adeli Beatriz | Thomé, Antônio
Nanoscale zero-valent iron (nZVI) is the main nanomaterial used in environmental remediation processes. The present study aims to evaluate the life cycle sustainability of nZVI production methods applied in environmental remediation. Three production methods of nZVI were selected for analysis: milling, liquid reduction with sodium borohydride, and chemical reduction with hydrogen gas (in two approaches: considering the goethite and hematite synthesis and after using in nZVI production and, using goethite and hematite particles already synthesized for nZVI production). The life cycle sustainability assessment was carried out based on a multi-criteria and multi-attribute analysis. The multi-criteria analysis was used to determine impact category preferences of different specialists in sustainability and remediation, and calculate the sustainability score through a linear additive model. Finally, a Monte Carlo simulation was used to quantify the results uncertainty. The functional unit considered was 1.00 kg of nZVI produced. The milling method and the hydrogen gas method in approach considering the use goethite and hematite particles already synthesized were the most sustainable. Moreover, the sustainability index was found to be influenced by the considered location scenarios as well as the perspectives of the different specialists, which was essential in producing a more accurate and comprehensive evaluation of the aforementioned sustainability methods. Overall, this study significantly contributed to applications of the state-of-the-art life cycle sustainability assessment in studies regarding nanomaterials, employing a simple methodology that included an analysis of different specialists. In addition, this is the first article that uses life cycle sustainability assessment in nanomaterials.
Show more [+] Less [-]Nitrogen flows associated with food production and consumption system of Shanghai Full text
2021
Liao, Chengsong | Xia, Yuling | Wu, Dianming
The release of reactive nitrogen (Nᵣ) from food production and consumption constitute the primary source of nitrogen pollution. However, nitrogen flows and the driving factors of food chain of Shanghai, China have not been previously studied. Here, we used a substance flow analysis model to analyze the changes in Nᵣ inputs and outputs in agricultural production, livestock and poultry farming, and food consumption related to the Shanghai food chain between 2000 and 2018. The driving forces of Nᵣ inputs, Nᵣ use efficiency, and Nᵣ surpluses/deficits in the food production and consumption system were also investigated. The results indicated that the main sources of Nᵣ input in the food production and consumption system were nitrogen fertilizers, livestock and poultry feed from external sources, and plant-based foods, which accounted for 36.28–59.45% of Nᵣ input in agricultural production, 37.32–76.57% of Nᵣ input in livestock and poultry farming, and 35.38–59.37% of Nᵣ input in food consumption, respectively. The main forms of Nᵣ outputs were surplus nitrogen in the soil, excretal nitrogen from livestock and poultry animals, and excretal nitrogen from humans, which accounted for 38.2–48.89% of Nᵣ output in agricultural production, 36.78–55.18% of Nᵣ output in livestock and poultry farming, and 85.36% of Nᵣ output in food consumption, respectively. From 2000 to 2018, the Nᵣ inputs per unit area from agricultural production decreased at a rate of 20.42% before 2012, and then increased at a rate of 5.72%. Moreover, the Nᵣ use efficiency of agricultural production component of Shanghai was at a low level, only 18.43–27.6%. Cultivation area of crops was the main driving forces of the Nᵣ input to food production and consumption system. These results provide essential data for controlling nitrogen pollution caused by Shanghai food production and consumption, which can serve as a reference for administrative agencies in formulating policies.
Show more [+] Less [-]Proinflammatory lipid signals trigger the health effects of air pollution in individuals with prediabetes Full text
2021
Wang, Teng | Han, Yiqun | Li, Haonan | Wang, Yanwen | Chen, Xi | Chen, Wu | Qiu, Xinghua | Gong, Jicheng | Li, Weiju | Zhu, Tong
Individuals with metabolic disorders exhibit enhanced susceptibility to the cardiovascular health effects of particulate air pollution, but the underlying mechanisms are not yet understood. We aim to assess whether changes in proinflammatory lipid signals are associated with fine particulate matter (PM₂.₅) exposure in individuals with and without prediabetes. A longitudinal panel study was conducted in Beijing, China, and included 120 participants followed up over 589 clinical visits from August 2013 to February 2015. We measured 12 lipids derived from arachidonic acid pathways in blood samples of the participants via targeted lipidomic analyses. Ambient PM₂.₅ concentrations were continuously monitored at a station for associations with the lipids. Among the 120 participants, 110 (mean [SD] age at recruitment, 56.5 [4.2] years; 31 prediabetics) who visited the clinic at least twice over the follow-up period were assigned exposure values of the outdoor residential PM₂.₅ concentrations during the 1–14 days preceding each clinical visit. With an interquartile range increase in the 1-day-lag PM₂.₅ exposure (64.0 μg/m³), the prediabetic group had consistently greater increases in the concentration of arachidonate metabolites derived from the cytochrome P450 (CYP450) pathway (5,6-DHET, 15.8% [95% CI, 3.5–29.7%]; 8,9-DHET, 9.7% [95% CI, 0.6–19.6%]; 11,12-DHET, 8.3% [95% CI, 1.9–15.1%]; 14,15-DHET, 7.4% [95% CI, 0.9–14.4%]; and 20-HETE, 8.9% [95% CI, 1.0–17.5%]), compared with the healthy group. Among CYP450-derived lipids, 14,15-DHET and 20-HETE significantly mediated 8% and 8% of the PM₂.₅-associated increase in white blood cells, 10% and 13% of that in neutrophils, and 20% and 23% of that in monocytes, respectively, in the prediabetic group. In conclusion, proinflammatory lipid signals from CYP450 pathways triggered the health effects of particulate air pollution in individuals with prediabetes, suggesting that targeting lipid metabolism has therapeutic potential to attenuate or prevent the cardiovascular effects of air pollution in susceptible populations.
Show more [+] Less [-]Spider web biomonitoring: A cost-effective source apportionment approach for urban particulate matter Full text
2021
van Laaten, Neele | von Tümpling, Wolf | Merten, Dirk | Bro, Rasmus | Schäfer, Thorsten | Pirrung, Michael
Elevated levels of particulate matter (PM) in urban atmospheres are one of the major environmental challenges of the Anthropocene. To effectively lower those levels, identification and quantification of sources of PM is required. Biomonitoring methods are helpful tools to tackle this problem but have not been fully established yet. An example is the sampling and subsequent analysis of spider webs to whose adhesive surface dust particles can attach. For a methodical inspection, webs of orb-weaving spiders were sampled repeatedly from 2016 to 2018 at 22 locations in the city of Jena, Germany. Contents of Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Si, Sn, Sr, Th, Ti, V, Y, Zn and Zr were determined in the samples using inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) after aqua regia digestion.Multivariate statistical methods were applied for a detailed evaluation. A combination of cluster analysis and principal component analysis allows for the clear identification of three main sources in the study area: brake wear from car traffic, abrasion of tram/train tracks and particles of geogenic origin. Quantitative source contributions reveal that high amounts of most of the metals are derived from a combination of brake wear and geogenic particles, the latter of which are likely resuspended by moving vehicles. This emphasizes the importance of non-exhaust particles connected to road traffic.Once a source identification has been performed for an area of interest, classification models can be applied to assess air quality for further samples from within the whole study area, offering a tool for air quality assessment. The general validity of this approach is demonstrated using samples from other locations.
Show more [+] Less [-]Functional involvement of caleosin/peroxygenase PdPXG4 in the accumulation of date palm leaf lipid droplets after exposure to dioxins Full text
2021
Hanano, Abdulsamie | Shaban, Mouhnad | Murphy, Denis J.
Dioxins are highly injurious environmental pollutants with proven toxicological effects on both animals and humans, but to date their effects on plants still need to be studied in detail. We identified a dioxin-inducible caleosin/peroxygenase isoform, PdPXG4, that is mostly expressed in leaves of date palm seedlings and exhibits a specific reductase activity towards the 13-hydroperoxide of C18:2 and C18:3 (HpODE and HpOTrE, respectively). After exposure to TCDD, lipid droplets (LDs) isolated from TCDD-exposed leaves were about 6.5–15.7-fold more active in metabolizing 13-HpOTrE compared with those isolated from non-exposed leaves. A characteristic spectrum of leaf dioxin-responsive oxylipins (LDROXYL) was detected in dioxin-exposed seedlings. Of particular importance, a group of these oxylipins, referred to as Class I, comprising six congeners of hydroxides fatty acids derived from C18:2 and C18:3, was exclusively found in leaves after exposure to TCDD. The TCDD-induced oxylipin pattern was confirmed in vitro using terbufos, a typical inhibitor towards the PdPXG4 peroxygenase activity. Of particular interest, the response of terbufos-pretreated protoplasts to TCDD was drastically reduced. Together, these findings suggest that PdPXG4 is implicated in the establishment of a dioxin-specific oxylipin signature in date palm leaves soon after their exposure to these pollutants.
Show more [+] Less [-]Concentrations and distributions of neonicotinoids in drinking water treatment plants in South Korea Full text
2021
Kim, Jiwon | Wang, Wenting | Lee, Soohyung | Park, Ju-Hyun | Oh, Jeong-Eun
We investigated the fates of seven neonicotinoids (NNIs) in full-scale drinking water treatment plants and assessed human exposure to NNIs through consuming drinking water. The total NNI concentrations in raw water and treated water samples from the drinking water treatment plants were 20.4–166 ng/L (median 118 ng/L) and 1.11–94.7 ng/L (median 20.4 ng/L), respectively. The dinotefuran (DIN) concentrations in raw water collected in different seasons were different, and the highest DIN concentration was found in summer. The drinking water treatment processes removed >91% of the NNIs except DIN and thiamethoxam (THIAM), for which the mean removal rates were 70% and 74%, respectively. The removal rates for all of the NNIs were higher for the granular activated carbon filtration process (mean 83.5%) than the other drinking water treatment plant processes (coagulation/sedimentation 22.3%, ozonation 29.2%). However, the removal rates in the granular activated carbon process were lower for DIN and THIAM (61.0% and 59.2%, respectively) than the other NNIs. Significant correlations were found between the NNI removal rates and physicochemical properties (solubility in water and log (octanol–water partition coefficient)). The estimated mean human exposure to NNIs in drinking water was 0.528 ng/(kg body weight d).
Show more [+] Less [-]Antibiotics in mariculture organisms of different growth stages: Tissue-specific bioaccumulation and influencing factors Full text
2021
Zhang, Xuanrui | Zhang, Jiachao | Han, Qianfan | Wang, Xiaoli | Wang, Shuguang | Yuan, Xianzheng | Zhang, Baiyu | Zhao, Shan
Maricultured organisms are chronically exposed to water containing antibiotics but the bioaccumulative behavior of antibiotics in exposed organisms at different growth stages has received little attention. Here, we investigated the concentrations and tissue-specific bioaccumulation characteristics of 19 antibiotics during three growth stages (youth stage, growth stage, and adult stage) of various organisms (Scophthalmus maximus, Penaeus vannamei, Penaeus japonicus, and Apostichopus japonicus) cultivated in typical marine aquaculture regions, and explored the factors that could affect the bioaccumulation of antibiotics. Tetracyclines (TCs) and fluoroquinolones (FQs) were the dominant antibiotics in all organisms, and the total concentrations of the target antibiotics in fish (S. maximus) were significantly higher than those in shrimp (P. vannamei and P. japonicus) and sea cucumber (A. japonicus) (p < 0.01). The bioaccumulation capacity of a class of statistically significant antibiotics in most samples was strongest during the youth stage and weakest during the adult stage. The antibiotics exhibited higher bioaccumulation capacity in lipid-rich tissues (fish liver and shrimp head) or respiratory organs (fish gill) than muscle. Our results also reveal significant metabolic transformation of enrofloxacin in fish. Different from previous studies, the logarithm bioaccumulation factor (log BAF) was positively correlated with log Dₗᵢₚw in low-biotransformation tissues (fish gill and muscle) rather than lipid-rich tissues (fish liver). Based on the calculated hazard quotients (HQ), doxycycline in fish muscle may pose a distinct risk to human health, which deserves special attention. Overall, these results provide insight into the bioaccumulation patterns of antibiotics during different growth stages and tissues of maricultured organisms.
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