Atmospheric Pollution Research
·
2018
·
IF 2.152
Longchao Liang,Zhidong Xu,Guangle Qiu,Pan Wu,Ruixue Zhang
Arsenic (As) is considered a carcinogenic toxin, and nonferrous metal smelting activities can release significant quantities of As, causing an increase in As levels in the environment. A total of 221 samples of moss belonging to 5 species in 4 families were collected from the Wanshan District, the world third largest mercury mining area, in Guizhou Province, southwestern China, for analysis of total As (tAs) concentrations and As speciation. The results indicated that the tAs concentrations in these mosses ranged from 0.67 to 9.6 mg kg −1 , with an average of 2.4 ± 1.7 mg kg −1 . The dominant species of As in these mosses were inorganic forms of arsenite (As(III)) and arsenate (As(V)) with a total percentage of 87%, whereas the concentrations of organic forms (monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) were relatively low, with percentages of 11.8% and 6.0%, respectively. A significant correlation (r = 0.766, p < 0.01) was observed between As(V) and tAs. In the spatial distribution pattern of As, high concentrations of As in mosses were centralized around historical Hg retorting sites in the town of Wanshan, the villages of Gouxi and Yanwuping and sites downwind of these locations, suggesting that historical intensive Hg mining activities might be the most possible source of atmospheric As.
研究领域:
环境科学
·
植物学
·
生态毒理学
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产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2024
·Vol. 57
·期 59
·28947-28956
·
IF 1
Qiao Wang,Guang-shan Zhang,Han Chen,Peng Wang
A specially designed combined process of pre-oxidation and nanofiltration membrane was utilized to remove As(III) in the contaminated water without reagent addition and sediment creation in this work. Different parameters that affected the rejections of As(III) and As(V) were discussed, including the initial concentration, pH of the feed, and the cross-flow filtration pressure. The rejection of As(III) was over 70% which was restricted to the high initial feed concentration, while it was around 40% under the other conditions. Whereas, the rejection of As(V) maintained above 95% in all tests. As a result, As(III) was first pre-oxidized before membrane filtration. The ozone and aeration oxidation methods were used to oxidize As(III). The effects of aeration time and oxidation time were studied. The experimental results indicated that the rejection of As(III) was increased to over 90% after pre-oxidation, and the permeate could meet the drinking water standard for As in China. Particularly, the aeration took a much longer oxidation time than ozone, but it was still a more suitable method as the pre-oxidation process because of its safety and easy operability.
研究领域:
环境工程
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水处理技术
·
膜分离
·
污染物控制
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DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2025
·
IF 3.1
Liu Jiang,Tang Chaobo,Yang Jianguang,Nan Tianxiang,Zhu Qiang,Tang Shiyang,Fan Xiao-Bin
Arsenic is removed in the refining process of crude antimony in traditional antimony smelting, which produces a lot of arsenic-alkali-residue (AAR). This study proposes a two-stage roasting process to retain arsenic during volatile roasting of antimony sulfide concentrates. Calcium oxide was employed to retain arsenic in the calcine at low temperature, while antimony was volatilized into the fume as antimony trioxide at high temperature. The feasibility was verified by thermodynamic calculations. The effects of different factors on the volatilization efficiency of antimony and the retention efficiency of arsenic were investigated. Moreover, the leaching toxicity of arsenical calcine was tested. The volatilization efficiency of antimony and retention efficiency of arsenic were 93.06 and 70.12 pct at optimized conditions, respectively. The leaching concentration of arsenic in the arsenic retention calcine (below 5 mg·L −1 ) was far less than the leaching concentration of arsenic in AAR (915 mg·L −1 ).
研究领域:
冶金学
·
环境科学
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产品关联
DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2025
·Vol. 19
·期 8
·1-13
·
IF 6.4
Shi Lin,Zhan Cetao,Bai Wenjing,Wang Wei,Yuan Shoujun,Hu Zhen-Hu
Arsanilic acid ( p -ASA), an organoarsenic additive found in livestock wastewater, can release toxic inorganic arsenic into the environment. While bioelectrochemical systems have proven effective in decomposing organoarsenics, managing the resulting inorganic arsenic remains a challenge. This study demonstrated the feasibility of a two-stage bioelectrochemical process designed to facilitate p -ASA degradation and in situ recover inorganic arsenic from contaminated livestock wastewater. It consisted of two sequential stages: (I) anodic stimulation for p -ASA degradation and (II) reversing electrode polarities for the cathodic reduction of inorganic arsenic. In Stage I, the anode significantly enhanced the degradation of p -ASA, resulting in 18 μg/L of As(III) and 700 μg/L of As(V) released into the bulk solution. In Stage II, the cathode further reduced the As(III) and As(V) to 8.9 and 35.5 μg/L, respectively, through the synergistic action of the cathode and suspended microbes. The inorganic arsenic was recovered as a layer of As(V)-O on the cathode. Microbial analysis indicated that Alcaligenes was responsible for the degradation of p -ASA, while Anaerobacillus and Desulfitibacter played key roles in reducing As(V) and As(III) on the cathode, respectively. This study provided a promising alternative approach for the removal of organoarsenics and in situ recovery of inorganic arsenic from organoarsenic-bearing wastewater.
研究领域:
环境科学
·
微生物学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2016
·
IF 5.393
Xue Liu,Jing-Wei Fu,Dong-Xing Guan,Yue Cao,Jun Luo,Bala Rathinasabapathi,Yanshan Chen,Lena Q. Ma
Arsenic hyperaccumulator Pteris vittata (PV) is efficient in taking up As and nutrients from As-contaminated soils. We evaluated the mechanisms used by PV to mobilize As and Fe by examining the impacts of As and root exudates on FeAsO4 solubilization, and As and Fe uptake in four plants: As-hyperaccumulators PV and Pteris multifida (PM), nonhyperaccumulator Pteris ensiformis (PE), and angiosperm plant tomato (Solanum lycopersicum). Phytate and oxalate were dominant in fern plants (>93%), which were 50–83, 15–42, and 0–32 mg kg–1 phytate and 10–15, 7–26, and 4–12 mg kg–1 oxalate for PV, PM, and PE respectively, with higher As inducing greater phytate exudation and no phytate being detected in tomato exudates. PV treated with phytate+FeAsO4 had higher As and Fe contents and larger biomass than phytate or FeAsO4 treatment, which were 340 vs 20 and 130 mg kg–1 As in the fronds and 7900 vs 1600 and 4100 mg kg–1 Fe in the roots. We hypothesized that As-induced phytate exudation helped PV to take up Fe and As from insoluble FeAsO4 and promoted PV growth. Our study suggests that phytate exudation may be special to fern plants, which may play an important role in enhancing As and nutrient uptake by plants, thereby increasing their efficiency in phytoremediation of As-contaminated soils.
研究领域:
植物学
·
环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Chuxuan Zhao,Zixin Liu,Yi Wu,Juntao Guo,Peng Huang,Yifei Wang,Yeheng Leng,Ivan P. Pozdnyakov,Jing Xu,Feng Wu
The widespread used organic arsenic pesticides and veterinary drugs have drawn attention for decades. Its photochemical transformation in the surface water contributes to its degradation and the formation of products. The effect of co-existent components like anthropogenic reagents (e.g. ethylenediaminetetraacetatic acid, EDTA) on the photochemical transformation has still to be investigated in depth. Fe(III)-EDTA complex is a common and abundant complex in surface water. In this work, UVA light and simulated sunlight have been used as light sources to explore the effect of Fe(III)-EDTA on the photodegradation of p -arsanilic acid (ASA), used as an organic arsenic feed additive. Whereas ASA hardly absorbs UVA light and can only be directly photolyzed by simulated sunlight, the Fe(III)-EDTA complex is photoactive under either light source. At pH 6, the presence of Fe(III)-EDTA complex enhances the photodegradation efficiency of ASA from 0% to ca. 23% after 180 min reaction under UVA light irradiation, and from 30% to ca. 58% after 45 min reaction under simulated sunlight irradiation. Appropriate amount of EDTA enhances the photodegradation efficiency, whereas excessive EDTA suppresses the initial reaction rate. Mechanistic study has revealed contributions from direct photolysis and photochemical reactions of Fe(III)-EDTA and Fe(III)–OH complexes. Generated •OH has been confirmed as the important contribution. Photodegradation products include inorganic arsenic, organic arsenic, and other organic by-products, and the proportions of these products vary in different light-induced systems due to the diverse reaction pathways. The results of this work improve our understanding of the risks of residual ASA in the environment, allow prediction of its migration and transformation, and show how organic arsenic livestock and poultry feed additives might be removed.
研究领域:
环境科学
·
化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Yu Yong,Hu Jianhang,Li Yongkui,Zhong Dapeng,Wang Hua
Arsenic ( As ) -bearing gypsum sludge, one of the biggest As-bearing wastes, has seriously threatened ecological security due to the great mobility and leaching toxicity of As. Unfortunately, most of this sludge was discharged into tailing ponds without treatment. In this paper, a novel co-process of As-bearing gypsum sludge, waste carbon cathode (WCC) and Fe powder for simultaneous separation and solidification of As is proposed via reduction-magnetic separation. In the reduction process, Ca 3 (AsO 4 ) 2 was reduced and then enriched to α-Fe (Fe-As solid solution), and the As solidification ratio reached 90.5%. Meanwhile, NaF in waste carbon cathodes was transformed into CaF 2 and NaCa 2 FSiO 4 . The As and F leached content were only 0.053 mg/L and 3.10 mg/L, when evaluated using the toxicity characteristic leaching procedure. After magnetic separation, α-Fe (magnetic phase) was separated and recovered, and the weight and volume losses of As-bearing waste were 70% and 60%, respectively, compared with the raw material. The As residual content in the non-magnetic phase met the standard of solid waste (As < 0.1 wt%), which acted as a flux during the smelting process, minimizing the environmental risk and realizing resource recycling. Moreover, waste carbon cathodes can be reused as fuel and as a reducing agent, which significantly reduces production costs. This proposed technique reduces hazardous waste, is more effective, and is also more economical.
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
Foods
·
2024
·Vol. 13
·期 17
·2741
·
IF 4.7
Di Zhao
Arsenic (As) contamination in rice is a global public health concern, particularly in Asian countries where rice is the staple food. Current health-based limits for As in rice are typically derived from total As concentrations, resulting in overly stringent values. This study aimed to determine As bioaccessibility in rice, estimate dietary intakes of inorganic As (iAs) at different consumption rates, evaluate the cancer and non-cancer risks associated with iAs exposure through rice consumption, and assess the feasibility of deriving more accurate health-based limits for As in rice after incorporating rice As bioaccessibility. Bioaccessibility of As ranged from 60.7% to 104.5% in rice samples. Estimated iAs intake varied from 0.04 to 1.40 μg/kg BW/day at rice consumption rates of 100–300 g/day. Incorporating rice As bioaccessibility resulted in lower iAs intake estimates of 0.03–1.18 μg/kg BW/day. The non-cancer and cancer risks associated with iAs exposure are concerning for populations with higher rice consumption rates and elevated rice iAs concentrations. Health-based limits for iAs in rice for different regions across China are discussed after incorporating rice As bioaccessibility. This study contributes to the development of regional or national safety limits for As in rice, based on As bioaccessibility in rice.
研究领域:
环境科学
·
公共卫生
·
毒理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Yanbiao Liu,Shengnan Yang,Hualin Jiang,Bo Yang,Xiaofeng Fang,Chensi Shen,Jianmao Yang,Wolfgang Sand,Fang Li
Advanced nanotechnologies for efficient arsenic decontamination remain largely underdeveloped. The most abundant inorganic arsenic species are neutrally-charged arsenate, As(III), and negatively-charged arsenite , As(V). Compared with As(V), As(III) is 60 times more toxic and more difficult to remove due to high mobility. Herein, an electrochemical filtration system was rationally designed for one-step As(III) decontamination . The key to this technology is a functional electroactive carbon nanotube (CNT) filter functionalized with sea urchin-like FeOOH. With the assistance of electric field, CNT-FeOOH anodic filter can in situ transform As(III) to less toxic As(V) while passing through. Then, as-produced As(V) could be effectively sequestrated by FeOOH. The sufficient exposed sorption sites, flow-through design, and filter’s electrochemical reactivity synergistically guaranteed a rapid arsenic removal kinetic. The underlying working mechanism was unveiled based on systematic experimental investigations and theoretical calculations. The system efficacy can be adapted across a wide pH range and environmental matrixes. Exhausted CNT-FeOOH filters could be effectively regenerated by chemical washing with diluted NaOH solution. Outcomes of the present study are dedicated to provide a straightforward and effective strategy by integrating electrochemistry , nanotechnology, and membrane separation for the removal of arsenic and other similar heavy metals from water bodies.
研究领域:
环境科学
·
纳米技术
·
电化学工程
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DOI
PubMed
高影响因子
PLoS One
·
2014
·Vol. 9
·期 6
·e100704
·
IF 3.534
Shams Ali Baig,TianTian Sheng,Chen Sun,XiaoQin Xue,LiSha Tan,XinHua Xu
The presence of elevated concentration of arsenic in water sources is considered to be health hazard globally. Calcination process is known to change the surface efficacy of the adsorbent. In current study, five adsorbent composites: uncalcined and calcined Fe 3 O 4 -HBC prepared at different temperatures (400°C and 1000°C) and environment (air and nitrogen) were investigated for the adsorptive removal of As(V) and As(III) from aqueous solutions determining the influence of solution's pH, contact time, temperature, arsenic concentration and phosphate anions. Characterizations from FTIR, XRD, HT-XRD, BET and SEM analyses revealed that the Fe 3 O 4 -HBC composite at higher calcination temperature under nitrogen formed a new product (fayalite, Fe 2 SiO 4 ) via phase transformation. In aqueous medium, ligand exchange between arsenic and the effective sorbent site ( = FeOOH) was established from the release of hydroxyl group. Langmuir model suggested data of the five adsorbent composites follow the order: Fe 3 O 4 -HBC-1000°C(N 2 )>Fe 3 O 4 -HBC (uncalcined)>Fe 3 O 4 -HBC-400°C(N 2 )>Fe 3 O 4 -HBC-400°C(air)>Fe 3 O 4 -HBC-1000°C(air) and the maximum As(V) and As(III) adsorption capacities were found to be about 3.35 mg g −1 and 3.07 mg g −1 , respectively. The adsorption of As(V) and As(III) remained stable in a wider pH range (4–10) using Fe 3 O 4 -HBC-1000°C(N 2 ). Additionally, adsorption data fitted well in pseudo-second-order ( R 2 >0.99) rather than pseudo-first-order kinetics model. The adsorption of As(V) and As(III) onto adsorbent composites increase with increase in temperatures indicating that it is an endothermic process. Phosphate concentration (0.0l mM or higher) strongly inhibited As(V) and As(III) removal through the mechanism of competitive adsorption. This study suggests that the selective calcination process could be useful to improve the adsorbent efficiency for enhanced arsenic removal from contaminated water.
研究领域:
环境科学
·
材料科学
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DOI
PubMed
高影响因子
ECOTOXICOLOGY
·
2017
·Vol. 26
·期 2
·202-210
·
IF 1.951
Ding Tengda,Zhang Jianying,Ni Wanmin,Li Juying
The toxicity and bioavailability of single arsenic species have been widely investigated, however, the biological effects of mixed arsenic species co-existing in natural waters still remain unknown. The objective of this work was to discern the adverse effects of combined arsenite (As(III)) and dimethylarsenic acid (DMA) on diatom Nitzschia palea . The combined ecotoxicity of As(III) and DMA on N. palea was observed to be time-dependent and showed dose-effect relation. The toxicity of DMA and As(III) mixture was higher than individual DMA or As(III) when the As(III) concentration was in the range of 0.085–0.316 mg L −1 . As the As(III) concentration increased from 0.487 to 0.858 mg L −1 , the antagonistic effect was found, which could be due to the higher thiols contents in the thiol-containing proteins (e.g., frustulins, silaffins and other glycoproteins). The content of malondialdehyde (MDA) in the treatment of mixed arsenic species was found to be at the same level compared to the As-free control after 72 h of exposure, indicating that the co-toxicity of As(III) and DMA on diatom frustules was not significant. Furthermore, the increase of frustule formation rate in the mixture of EC 50 As(III)-EC 10 DMA at 72 h exposure time indicated that the damaged diatom cell walls was likely repaired gradually. The results from this study suggested that the effects of co-existed arsenic species were concentration-specific and should be considered in the risk assessment of arsenic and development of water quality criteria for the protection of aquatic ecosystems.
研究领域:
环境生物学
·
生态毒理学
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产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Shiqi Tian,Yuwei Ma,Yuanyuan Xu,Yingzi Lin,Jun Ma,Gang Wen
Dissolved Mn(III), as a potent one-electron transfer oxidant, is ubiquitous in natural waters and sediments and actively involved in the transformation of organics in biogeochemical processes and water treatment. However, the important role of Mn(III) has long been overlooked because of its short life. This study was the first to investigate the performance of Mn(III) in organoarsenic transformation and to highlight the environmental implications. Both homogeneous and heterogeneous Mn(III)-based systems were effective to remove p -arsanilic acid ( p -ASA, 15 μ M) with degradation efficiency approaching 40.4 %–98.3 %. Two degradation pathways of p -ASA were proposed, in which As-C bond and amino group were vulnerable sites to Mn(III) attack, leading to the formation of more toxic arsenate (As(V)) and nitarsone. Through transforming organoarsenic to inorganic arsenic species, the removal efficiency of total arsenic and dissolved organics were enhanced to 65.1 %–95.5 % and 16.6 %–36.6 %, respectively, by post-treatment of coagulation or adsorption, accompanied with significant reduction of cytotoxicity and environmental risks. Particularly, polymeric ferric sulfate and granular activated alumina showed superior performance in the total As removal. Moreover, oxidation efficiency of Mn(III) was hardly affected by common cations and anions (e.g., Ca 2+ , Mg 2+ , NH 4 + , NO 3 ˉ, SO 4 ˉ), halide ions (e.g., Clˉ, Brˉ) and natural organic matter, showing high robustness for organoarsenic removal under complicated water matrices. Overall, this study shed light on the significance of Mn(III) to the fate of organoarsenics in manganese-rich environments, and demonstrated the promising potential of Mn(III)-based strategies to achieve targeted decontamination in water/wastewater purification.
研究领域:
环境科学
·
水处理工程
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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