RESUMEN
Petcoke generated during bitumen upgrading is a potential source of vanadium for the global market. Recovering vanadium from the fly ash originating from the combustion of petcoke appears to be a suitable route for commercial implementation, given its high extraction rate. Although the technical feasibility of the recovery process has been proven, the environmental impact should be addressed. Information on the greenhouse (GHG) emissions from the process is scarce in the public domain. Therefore, a framework was developed for assessment of life cycle GHG emissions for extraction of vanadium from petcoke-based fly ash. This framework was used to perform a life cycle GHG emissions assessment of a water leaching and salt roasting process to extract vanadium from fly ash. For the upstream GHG emissions, we collected direct emissions data and energy consumption from the literature, and, for the process emissions, we developed a model to estimate energy and material balances based on process conditions. The emission factors for electricity production, fuel combustion, production of consumables, and gas treatment were used to obtain the life cycle GHG emissions. The results show that the life cycle GHG emission of vanadium recovery are 26.6-3.9+0.9 kg CO2eq/kg V2O5; 66% of these are direct GHG emissions. The process GHG emissions from fly ash decarbonization contribute the most to the life cycle GHG emissions. The air-to-fuel ratio for roasting and the GHG emission factors for petcoke combustion and the gas treatment operation are the inputs that most effect the model output. Compared with the production of V2O5 from vanadium titano-magnetite ore and bitumen upgrading spent catalyst, the petcoke fly ash pathway generates about twice the life cycle GHG emissions. This study's results can help determine areas of improvement in the upstream operations and the recovery process to reduce the life cycle GHG emissions to levels that can compete with primary and alternative routes to produce vanadium pentoxide. The results of this study can help in decision-making associated with vanadium extract from fly ash produced from combustion of petcoke.
Asunto(s)
Ceniza del Carbón , Vanadio , Vanadio/análisis , Gases de Efecto Invernadero/análisis , Hidrocarburos/análisis , Efecto InvernaderoRESUMEN
BACKGROUND: An interlaboratory study was conducted at the U.S. Food and Drug Administration's (FDA) Northeast Food and Feed Laboratory (NFFL) and the Center for Food Safety and Applied Nutrition (CFSAN) with the purpose to expand FDA Elemental Analysis Manual (EAM) method 4.7 (Inductively Coupled Plasma-Mass Spectrometric Determination of Arsenic, Cadmium, Chromium, Lead, Mercury, and Other Elements in Food Using Microwave Assisted Digestion) to include new analytes. OBJECTIVE: The goal of the study was to demonstrate the performance of FDA EAM method 4.7 when analyzing new analytes cobalt (Co), strontium (Sr), thallium (Tl), tin (Sn), uranium (U), and vanadium (V). This analyte extension method validation of EAM 4.7 for six additional elements, Co, Sr, Tl, Sn, U, and V, followed all guidelines for a Level 2 or single-laboratory validation and met all acceptance criteria for analyte extensions as per the Guidelines for the Validation of Chemical Methods. METHOD: As per EAM 4.7, this study followed the procedures and used specified equipment operated under recommended conditions. The analyte extension method validation was performed in accordance with protocol and with no deviations. RESULTS: All quality control (QC) requirements for this analyte extension method validation of EAM 4.7 passed as evidenced by the analytical data. The results presented demonstrate accuracy, linearity, and precision by successful analyses of method blanks, matrix spikes, unfortified test samples, and reference materials. The data analyzed met each of the validation requirements for each analyte in all representative matrixes. CONCLUSIONS: The study showed that the new analytes performed satisfactorily using EAM 4.7 for total acidic extractable elemental analysis of food according to FDA's guidelines. HIGHLIGHTS: The method met or exceeded the performance criteria.
Asunto(s)
Cobalto , Estroncio , Talio , Estaño , Uranio , Cobalto/análisis , Talio/análisis , Uranio/análisis , Estaño/análisis , Estroncio/análisis , Vanadio/análisis , Análisis de los Alimentos/métodos , Espectrometría de Masas/métodos , Estados Unidos , United States Food and Drug AdministrationRESUMEN
Background: It has been reported that the disease-initiated and disease-mediated effects of aerosol pollutants can be related to concentration, site of deposition, duration of exposure, as well as the specific chemical composition of pollutants. Objectives: To investigate the microelemental composition of dust aggregates in primary schools of Vilnius and determine trace elements related to acute upper respiratory infections among 6-to 11-year-old children. Methods: Microelemental analysis of aerosol pollution was performed using dust samples collected in the classrooms of 11 primary schools in Vilnius from 2016 to 2020. Sites included areas of its natural accumulation behind the radiator heaters and from the surface of high cupboards. The concentrations of heavy metals (Pb, W, Sb, Sn, Zr, Zn, Cu, Ni, Mn, Cr, V, and As) in dust samples were analyzed using a SPECTRO XEPOS spectrometer. The annual incidence rates of respiratory diseases in children of each school were calculated based on data from medical records. Results: The mean annual incidence of physician-diagnosed acute upper respiratory infections (J00-J06 according to ICD-10A) among younger school-age children was between 25.1 and 71.3% per school. A significant correlation was found between vanadium concentration and the number of episodes of acute upper respiratory infections during each study year from 2016 to 2020. The lowest was r = 0.67 (p = 0.024), and the highest was r = 0.82 (p = 0.002). The concentration of vanadium in the samples of dust aggregates varied from 12.7 to 52.1 parts per million (ppm). No significant correlations between the other trace elements and the incidence of upper respiratory infections were found, which could be caused by a small number of study schools and relatively low concentrations of other heavy metals found in the samples of indoor dust aggregates. Conclusion: A significant and replicable correlation was found between the concentration of vanadium in the samples of natural dust aggregates collected in primary schools and the incidence of acute upper respiratory infections in children. Monitoring the concentration of heavy metals in the indoor environment can be an important instrument for the prevention and control of respiratory morbidity in children.
Asunto(s)
Contaminantes Ambientales , Metales Pesados , Infecciones del Sistema Respiratorio , Oligoelementos , Niño , Humanos , Polvo/análisis , Vanadio/análisis , Incidencia , Monitoreo del Ambiente , Oligoelementos/análisis , Aerosoles y Gotitas Respiratorias , Metales Pesados/análisis , Contaminantes Ambientales/análisis , Infecciones del Sistema Respiratorio/epidemiologíaRESUMEN
Although animal studies have shown the reproductive toxicity of vanadium, less is known about its effects on semen quality in humans. Among 1135 healthy men who were screened as potential semen donors, we investigated the relationships of semen quality with urinary and seminal plasma vanadium levels via inductively coupled plasma-mass spectrometry (ICP-MS). Spearman rank correlation tests and linear regression models were used to assess the correlations between average urinary and within-individual pooled seminal plasma vanadium concentrations (n = 1135). We utilized linear mixed-effects models to evaluate the associations of urinary and seminal plasma vanadium levels (n = 1135) with repeated sperm quality parameters (n = 5576). Seminal plasma vanadium concentrations were not significantly correlated with urinary vanadium concentrations (r = 0.03). After adjusting for possible confounders, we observed inverse relationships of within-individual pooled seminal plasma vanadium levels with total count, semen volume, and sperm concentration (all P values for trend < 0.05). Specifically, subjects in the highest (vs. lowest) tertile of seminal plasma vanadium concentrations had - 11.3% (-16.4%, -5.9%), - 11.1% (-19.1%, -2.4%), and - 20.9% (-29.0%, -11.8%) lower sperm volume, concentration, and total count, respectively; moreover, urinary vanadium levels appeared to be negatively associated with sperm motility. These relationships showed monotonically decreasing dose-response patterns in the restricted cubic spline analyses. Our results demonstrated a poor correlation between urinary and seminal plasma levels of vanadium, and elevated vanadium concentrations in urine and seminal plasma may be adversely related to male semen quality.
Asunto(s)
Análisis de Semen , Semen , Animales , Masculino , Humanos , Semen/química , Vanadio/toxicidad , Vanadio/análisis , Motilidad Espermática , Recuento de Espermatozoides , Espermatozoides/fisiologíaRESUMEN
Microbial reduction under anaerobic condition is a promising method for remediating vanadate [V(V)] contamination in aquifers, while V(V) may be re-generated with redox fluctuations. The inability to remove vanadium after remediation has become a key issue limiting bioremediation. In this study, we proposed the use of pyrrhotite, a natural mineral with magnetic properties, to immobilize V(V) to insoluble V(IV) under microbial action and remove vanadium from the aquifer using a magnetic field, which could avoid the problem of V(V) recontamination under redox fluctuating conditions. Up to 49.0 ± 4.7 % of vanadium could be removed from the aquifer by the applied magnetic field, and the vanadium in the aquifer after the reaction was mainly in the acid-extractable and reducible states. pH had a strong effect on the magnetic recovery of V(V), while the influence of initial V(V) concentration was weak. Microbial community structure analysis showed that Thiobacillus, Proteiniphilum, Fermentimonas, and Desulfurivibrio played key roles for V(V) reduction and pyrrhotite oxidation. Structural equation model indicated the positive correlation between these genera with the magnetic recovery of vanadium. Real time-qPCR confirmed the roles of functional genes of V(V) reduction (napA and nirK) and SO42- reduction (dsrA) in such biological processes. This study provides a novel route to sustainable V(V) remediation in aquifers, with synchronous recovery of vanadium resources without rebound.
Asunto(s)
Agua Subterránea , Vanadio , Vanadio/análisis , Oxidación-Reducción , Agua Subterránea/química , Biodegradación Ambiental , Fenómenos MagnéticosRESUMEN
BACKGROUND: Fungi absorb and solubilize a broad spectrum of heavy metals such as vanadium (V), which makes them a main route of its entry into the biosphere. V as vanadate (V5+) is a potential medical agent due to its many metabolic actions such as interaction with phosphates in the cell, and especially its insulin-mimetic activity. Antidiabetic activity of V-enriched fungi has been studied in recent years, but the biological and chemical bases of vanadium action and status in fungi in general are poorly understood, with almost no information on edible fungi. METHODS: This manuscript gives a deeper insight into the interaction of V5+ with Coprinellus truncorum, an edible autochthonous species widely distributed in Europe and North America. Vanadium uptake and accumulation as V5+ was studied by 51V NMR, while the reducing abilities of the mycelium were determined by EPR. 31P NMR was used to determine its effects on the metabolism of phosphate compounds, with particular focus on phosphate sugars identified using HPLC. RESULTS: Vanadate enters the mycelium in monomeric form and shows no immediate detrimental effects on intracellular pH or polyphosphate (PPc) levels, even when applied at physiologically high concentrations (20 mM Na3VO4). Once absorbed, it is partially reduced to less toxic vanadyl (V4+) with notable unreduced portion, which leads to a large increase in phosphorylated sugar levels, especially glucose-1-phosphate (G1P) and fructose-6-phosphate (F6P). CONCLUSIONS: Preservation of pH and especially PPc reflects maintenance of the energy status of the mycelium, i.e., its tolerance to high V5+ concentrations. Rise in G1P and F6P levels implies that the main targets of V5+ are most likely phosphoglucomutase and phosphoglucokinase(s), enzymes involved in early stages of G6P transformation in glycolysis and glycogen metabolism. This study recommends C. truncorum for further investigation as a potential antidiabetic agent.
Asunto(s)
Agaricales , Vanadatos , Vanadio , Vanadio/análisis , Vanadatos/química , Biomasa , Fosfatos/análisis , Micelio/metabolismoRESUMEN
BACKGROUND: The relationship between long-term exposure to PM2.5 and mortality is well-established; however, the role of individual species is less understood. OBJECTIVES: In this study, we assess the overall effect of long-term exposure to PM2.5 as a mixture of species and identify the most harmful of those species while controlling for the others. METHODS: We looked at changes in mortality among Medicare participants 65 years of age or older from 2000 to 2018 in response to changes in annual levels of 15 PM2.5 components, namely: organic carbon, elemental carbon, nickel, lead, zinc, sulfate, potassium, vanadium, nitrate, silicon, copper, iron, ammonium, calcium, and bromine. Data on exposure were derived from high-resolution, spatio-temporal models which were then aggregated to ZIP code. We used the rate of deaths in each ZIP code per year as the outcome of interest. Covariates included demographic, temperature, socioeconomic, and access-to-care variables. We used a mixtures approach, a weighted quantile sum, to analyze the joint effects of PM2.5 species on mortality. We further looked at the effects of the components when PM2.5 mass levels were at concentrations below 8 µg/m3, and effect modification by sex, race, Medicaid status, and Census division. RESULTS: We found that for each decile increase in the levels of the PM2.5 mixture, the rate of all-cause mortality increased by 1.4% (95% CI: 1.3%-1.4%), the rate of cardiovascular mortality increased by 2.1% (95% CI: 2.0%-2.2%), and the rate of respiratory mortality increased by 1.7% (95% CI: 1.5%-1.9%). These effects estimates remained significant and slightly higher when we restricted to lower concentrations. The highest weights for harmful effects were due to organic carbon, nickel, zinc, sulfate, and vanadium. CONCLUSIONS: Long-term exposure to PM2.5 species, as a mixture, increased the risk of all-cause, cardiovascular, and respiratory mortality.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Enfermedades Respiratorias , Humanos , Anciano , Estados Unidos/epidemiología , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Material Particulado/toxicidad , Material Particulado/análisis , Contaminación del Aire/análisis , Níquel , Vanadio/análisis , Medicare , Enfermedades Respiratorias/etiología , Carbono/análisis , Sulfatos , Zinc/análisis , Exposición a Riesgos Ambientales/análisisRESUMEN
The trace elements present in breast milk play a vital role in the growth and development of infants. Nevertheless, numerous studies have reported the presence of toxic metal contamination in breast milk from various countries and regions, which poses potential risks to breastfed infants. This article aimed to investigate the characteristics of trace elements in breast milk and explore the relationship between breast milk and diet in Dalian, a coastal city in northeastern China. Breast milk samples and representative local food samples were collected from Dalian for research. The results revealed that 57 % of breast milk samples significantly exceeded the WHO safety limit (0.6 µg/L) for arsenic, with a measured mean value of 0.96 µg/L. Moreover, the levels of chromium (mean value: 2.63 µg/L) in 34 % of breast milk samples exceed the WHO recommended safety level (chromium: 1.5 µg/L). Aquatic foods accounted for 60 % to 90 % of the total intake of arsenic, cadmium, vanadium, mercury, and lead. The Spearman correlation analysis demonstrated strong positive correlations among breast milk metal elements, including copper-zinc (r = 0.68) and nickelchromium (r = 0.89). Furthermore, the food-to-milk accumulation factors (FMAF) of strontium, nickel, arsenic, vanadium, cadmium, and mercury were relatively low (median values <0.005). While the FMAF values for chromium and lead were higher, with median values of 0.038 and 0.07, respectively. The results indicated potential risks of the toxic metal arsenic in breast milk from Dalian, China for breastfed infants. Therefore, continuous monitoring of breast milk for toxic metals and foodborne contamination is necessary.
Asunto(s)
Intoxicación por Arsénico , Arsénico , Mercurio , Metales Pesados , Oligoelementos , Lactante , Femenino , Humanos , Cadmio/análisis , Arsénico/análisis , Leche Humana/química , Níquel/análisis , Oligoelementos/análisis , Vanadio/análisis , Mercurio/análisis , Cromo/análisis , Intoxicación por Metales Pesados , Ingestión de Alimentos , Metales Pesados/análisisRESUMEN
The metal vanadium has superior physical and chemical properties and has a wide range of applications in many fields of modern industry. The increasing demand for vanadium worldwide has led to the need to guarantee sustainable vanadium production. The smelting process of vanadium and titanium magnetite produces vanadium-bearing steel slag, a key material for vanadium extraction. Herein, vanadium production, consumption, and steel slag properties are discussed. A detailed review of methods for extracting vanadium from vanadium-bearing steel slag is presented, including the most commonly used roasting and leaching method, and direct leaching, bioleaching and enhanced leaching methods are also described. Finally, the rules and regulations of steel slag management are introduced. In general, it is necessary to further develop environmentally friendly vanadium extraction methods and technologies from vanadium containing solid wastes. This study provides research directions for the technology of vanadium extraction from steel slag.
Asunto(s)
Residuos Industriales , Vanadio , Vanadio/análisis , Residuos Industriales/análisis , Acero , Reciclaje , TitanioRESUMEN
The migration mechanism of vanadium (V) in the soil-pore water-maize system has not been revealed. This study conducted pot experiments under artificial control conditions to reveal V's distribution and transport mechanism under different growth stages and V content gradient stress. The V content in the soil pore water gradually increased by an order of magnitude. The V content of pore water in the no-plant group was higher than that in the plant group, indicating that the maize roots absorbed V. The V exists in the form of pentavalent oxygen anions, in which H2VO4- occupies the most significant proportion. With increasing V content, the root area, root number, root length, and tip number decreased significantly. The malondialdehyde content in maize leaves showed an increasing trend, indicating the degree of lipid peroxidation was gradually enhanced. The V content was in the order of root > leaf > stem > fruit and maturity stage > flowering stage > jointing stage, respectively. The transfer coefficient reached a maximum under natural conditions, and increased gradually with the growth. The results of synchrotron radiation X-ray absorption near edge structure (XANES) analysis showed that Fe in maize roots mainly comprised of Fe2O3 and Fe3O4. The Fe in the soil is primarily existed in lepidocrocite and Fe2O3. The µ-XRF analysis showed that V and Fe enriched in the roots with a positive relationship, indicating the synergistic absorption of V and Fe by roots. Part of the Fe2+ reduced V5+ to V4+ or V3+ in the forms of VO2+, V(OH)2+, or V(OH)3 (s), and fixed V at the root. Soil weak acid-soluble fraction V and soil total V were vital factors to maize extraction. This study provides new insights into V biogeochemical behavior and a scientific basis for correctly evaluating its ecological and human health risks.
Asunto(s)
Suelo , Vanadio , Humanos , Suelo/química , Vanadio/análisis , Zea mays , Agua/análisis , Raíces de Plantas/químicaRESUMEN
Vanadium (V) contamination in soil has received extensive attention due to its high toxicity. The change of mobility and bioavailability of soil V and the effects of V on the soil microbial community were studied under conditions of different V(V) spiking concentrations (0, 100, 250, and 500 mg kg-1) and aging time (1, 7, 14, 30, 45, and 60 d). The results showed that soil V mainly presented as V(IV) of all treatments throughout the aging process. At high levels of V(V) loading (250 and 500 mg kg-1), soil V(V) showed a downward trend, while bioavailable V did not change significantly within 60 d's aging. The analysis of soil bacterial community showed that Proteobacteria was the most abundant phylum in all soils, and the dominant genera Sphingomonas and Lysobacter can well adapt to high concentration V. These microorganisms exhibited great potential for bioremediation of V-contaminated soils.
Asunto(s)
Microbiota , Contaminantes del Suelo , Vanadio/toxicidad , Vanadio/análisis , Suelo/química , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Secuenciación de Nucleótidos de Alto Rendimiento , Microbiología del SueloRESUMEN
Vanadium(V) is a highly toxic multivalent, redox-sensitive element. It is widely distributed in the environment and employed in various industrial applications. Interactions between V and (micro)organisms have recently garnered considerable attention. This Review discusses the biogeochemical cycling of V and its corresponding bioremediation strategies. Anthropogenic activities have resulted in elevated environmental V concentrations compared to natural emissions. The global distributions of V in the atmosphere, soils, water bodies, and sediments are outlined here, with notable prevalence in Europe. Soluble V(V) predominantly exists in the environment and exhibits high mobility and chemical reactivity. The transport of V within environmental media and across food chains is also discussed. Microbially mediated V transformation is evaluated to shed light on the primary mechanisms underlying microbial V(V) reduction, namely electron transfer and enzymatic catalysis. Additionally, this Review highlights bioremediation strategies by exploring their geochemical influences and technical implementation methods. The identified knowledge gaps include the particulate speciation of V and its associated environmental behaviors as well as the biogeochemical processes of V in marine environments. Finally, challenges for future research are reported, including the screening of V hyperaccumulators and V(V)-reducing microbes and field tests for bioremediation approaches.
Asunto(s)
Suelo , Vanadio , Vanadio/análisis , Vanadio/química , Biodegradación Ambiental , Minerales , Oxidación-ReducciónRESUMEN
Welding fume is a common exposure in occupational settings. Gravimetric analysis for total particulate matter is common; however, the cost of laboratory analyses limits the availability of quantitative exposure assessment for welding fume metal constituents in occupational settings. We investigated whether a field portable X-ray fluorescence spectrometer (FP-XRF) could provide accurate estimates of personal exposures to metals common in welding fume (chromium, copper, manganese, nickel, vanadium, and zinc). The FP-XRF requires less training and is easier to deploy in many settings than traditional wet laboratory analyses. Filters were analyzed both by FP-XRF and inductively coupled plasma mass spectrometry (ICP-MS). We estimated the FP-XRF limit of detection for each metal and developed a correction factor accounting for the non-uniform deposition pattern on filter samples collected with an Institute of Medicine (IOM) inhalable particulate matter sampler. Strong linear correlation was observed for all metals (0.72Asunto(s)
Contaminantes Ocupacionales del Aire
, Exposición Profesional
, Soldadura
, Exposición Profesional/análisis
, Contaminantes Ocupacionales del Aire/análisis
, Acero Inoxidable/análisis
, Cobre/análisis
, Manganeso/análisis
, Níquel/análisis
, Rayos X
, Vanadio/análisis
, Monitoreo del Ambiente/métodos
, Cromo/análisis
, Zinc/análisis
, Espectrometría por Rayos X/métodos
, Gases/análisis
, Espectrometría de Masas/métodos
, Material Particulado/análisis
RESUMEN
Exposures to metals from industrial emissions can pose important health risks. The Chester-Trainer-Marcus Hook area of southeastern Pennsylvania is home to multiple petrochemical plants, a refinery, and a waste incinerator, most abutting socio-economically disadvantaged residential communities. Existing information on fenceline community exposures is based on monitoring data with low temporal and spatial resolution and EPA models that incorporate industry self-reporting. During a 3 week sampling campaign in September 2021, size-resolved particulate matter (PM) metals concentrations were obtained at a fixed site in Chester and on-line mobile aerosol measurements were conducted around Chester-Trainer-Marcus Hook. Fixed-site arsenic, lead, antimony, cobalt, and manganese concentrations in total PM were higher (p < 0.001) than EPA model estimates, and arsenic, lead, and cadmium were predominantly observed in fine PM (<2.5 µm), the PM fraction which can penetrate deeply into the lungs. Hazard index analysis suggests adverse effects are not expected from exposures at the observed levels; however, additional chemical exposures, PM size fraction, and non-chemical stressors should be considered in future studies for accurate assessment of risk. Fixed-site MOUDI and nearby mobile aerosol measurements were moderately correlated (r ≥ 0.5) for aluminum, potassium and selenium. Source apportionment analyses suggested the presence of four major emissions sources (sea salt, mineral dust, general combustion, and non-exhaust vehicle emissions) in the study area. Elevated levels of combustion-related elements of health concern (e.g., arsenic, cadmium, antimony, and vanadium) were observed near the waste incinerator and other industrial facilities by mobile monitoring, as well as in residential-zoned areas in Chester. These results suggest potential co-exposures to harmful atmospheric metal/metalloids in communities surrounding the Chester-Trainer-Marcus Hook industrial area at levels that may exceed previous estimates from EPA modeling.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Arsénico , Metales Pesados , Selenio , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Antimonio/análisis , Arsénico/análisis , Cadmio/análisis , Material Particulado/análisis , Polvo/análisis , Selenio/análisis , Vanadio/análisis , Aerosoles/análisis , Metalurgia , Metales Pesados/análisisRESUMEN
We determined reference intervals (RIs) for concentrations of trace minerals and toxic elements based on liver samples from 122 apparently healthy horses at 2 slaughter facilities in the Netherlands. Samples were collected during the spring and fall of 2021, and the sex and age of the horses were registered upon sampling. Concentrations of arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, vanadium, and zinc were measured in liver samples using inductively coupled plasma-mass spectrometry (ICP-MS) after nitric acid digestion. RIs were calculated using Reference Value Advisor software. The concentrations of most elements were not significantly different between sexes or in different seasons. Cadmium concentrations were higher than the European maximum residue limit of 2 mg/kg DW in 89% of livers. Positive significant correlations were observed between some elements (iron, molybdenum, lead, vanadium), and significant negative correlations between others (manganese, iron).
Asunto(s)
Metales Pesados , Selenio , Oligoelementos , Caballos , Animales , Manganeso , Molibdeno/análisis , Cadmio/análisis , Vanadio/análisis , Países Bajos , Metales Pesados/análisis , Cobre , Hierro/análisis , Hígado/químicaRESUMEN
Community gardens have been seen sprouting up in and around urban settings such as Philadelphia and Pittsburgh over the past several decades. Due to the long histories of industrial activities and urbanization, these soils in urban regions may be at a high risk for various contaminants such as metals and metalloids. Using inductively coupled plasma mass spectrometry (ICP-MS), we measured 7 elements (lead (Pb), zinc (Zn), copper (Cu), vanadium (V), cadmium (Cd), nickel (Ni), and arsenic (As)) in soil samples collected from a total of 21 community gardens in Philadelphia City, Philadelphia suburban areas, and Pittsburgh City during September and October 2021. We found that the city areas in Philadelphia and Pittsburgh had higher elemental concentrations in community garden soils compared to the suburbs. We found that all elements except vanadium were below the Pennsylvania Department of Environmental Protection (PADEP) guidelines. When compared to more stringent Canadian Council of Ministers of the Environment (CCME) guidelines of a maximum of 140 mg/kg of lead in the soil, 36% percent of Philadelphia community gardens, 60% of Pittsburgh gardens, and 20% of the Philadelphia suburb gardens exceeded the CCME guideline. In Philadelphia city, generally, elemental concentrations exhibited a negative trend with increasing distance to historical smelter locations, although a significant correlation was observed for only zinc. We found that the soil from the raised beds had lower concentrations of lead and arsenic, but many of the samples from the raised beds had higher concentrations of zinc, copper, vanadium, and nickel. This discrepancy in raised beds is most likely attributed to these elements being actively deposited in the soil from present day sources such as vehicles on the road and active industrial sites. Understanding and recognizing such variations of these contaminants in community gardens are essential to understanding how industrial legacies and modern pollution continue to put urban communities at a disproportionate risk of health impacts.
Asunto(s)
Arsénico , Metales Pesados , Contaminantes del Suelo , Jardines , Níquel/análisis , Cobre/análisis , Suelo/química , Vanadio/análisis , Arsénico/análisis , Philadelphia , Monitoreo del Ambiente/métodos , Canadá , Zinc/análisis , Contaminantes del Suelo/análisis , Metales Pesados/análisisRESUMEN
The environmental risks associated with the storage, reuse, and disposal of unencapsulated reclaimed asphalt pavement (RAP) has been previously examined, but because of a lack of standardized column testing protocols and recent interest on emerging constituents with higher toxicity, questions surrounding leaching risks from RAP continue. To address these concerns, RAP from six, discrete stockpiles in Florida was collected and leach tested following the most up-to-date, standard column leaching protocol - United States Environmental Protection Agency (US EPA) Leaching Environmental Assessment Framework (LEAF) Method 1314. Sixteen EPA priority polycyclic aromatic hydrocarbons (PAHs), 23 emerging PAHs, identified through relevance in literature, and heavy metals were investigated. Column testing showed minimal leaching of PAHs; only eight compounds, three priority PAHs and five emerging PAHs, were released at quantifiable concentrations, and where applicable, were below US EPA Regional Screening Levels (RSL). Though emerging PAHs were identified more frequently, in most cases, priority compounds dominated contributions to overall PAH concentration and benzo(a)pyrene (BaP) equivalent toxicity. Except for arsenic, molybdenum, and vanadium in two samples, metals were found below limits of detection (LOD) or below risk thresholds. Arsenic and molybdenum concentrations diminished over time with increased exposure to liquid, but elevated vanadium concentrations persisted in one sample. Further batch testing linked vanadium to the aggregate component of the sample, unlikely to be encountered in typical RAP sources. As demonstrated by generally low constituent mobility observed during testing, the leaching risks associated with the beneficial reuse of RAP are limited, and under typical reuse conditions, factors of dilution and attenuation would likely reduce leached concentrations below relevant risk-based thresholds at a point of compliance. When considering emerging PAHs with higher toxicities, analyses indicated minimal impact to overall leachate toxicity, further suggesting that with proper management, this heavily recycled waste stream is unlikely to pose leaching risk.
Asunto(s)
Arsénico , Hidrocarburos Policíclicos Aromáticos , Oligoelementos , Hidrocarburos Policíclicos Aromáticos/análisis , Vanadio/análisis , Arsénico/análisis , Molibdeno/análisis , Monitoreo del Ambiente/métodos , Oligoelementos/análisisRESUMEN
Vanadium-titanium (V-Ti) magnetite tailings contain toxic metals that could potentially pollute the surrounding environment. However, the impact of beneficiation agents, an integral part of mining activities, on the dynamics of V and the microbial community composition in tailings remains unclear. To fill this knowledge gap, we compared the physicochemical properties and microbial community structure of V-Ti magnetite tailings under different environmental conditions, including illumination, temperature, and residual beneficiation agents (salicylhydroxamic acid, sodium isobutyl xanthate, and benzyl arsonic acid) during a 28-day reaction. The results revealed that beneficiation agents exacerbated the acidification of the tailings and the release of V, among which benzyl arsonic acid had the greatest impact. The concentration of soluble V in the leachate of tailings with benzyl arsonic acid was 6.4 times higher than that with deionized water. Moreover, illumination, high temperatures, and beneficiation agents contributed to the reduction of V in V-containing tailings. High-throughput sequencing revealed that Thiobacillus and Limnohabitans adapted to the tailings environment. Proteobacteria was the most diverse phylum, and the relative abundance was 85.0%-99.1%. Desulfovibrio, Thiobacillus, and Limnohabitans survived in the V-Ti magnetite tailings with residual beneficiation agents. These microorganisms could contribute to the development of bioremediation technologies. The main factors affecting the diversity and composition of bacteria in the tailings were Fe, Mn, V, SO42-, total nitrogen, and pH of the tailings. Illumination inhibited microbial community abundance, while the high temperature (39.5 °C) stimulated microbial community abundance. Overall, this study strengthens the understanding of the geochemical cycling of V in tailings influenced by residual beneficiation agents and the application of inherent microbial techniques in the remediation of tailing-affected environments.
Asunto(s)
Contaminantes del Suelo , Vanadio , Vanadio/análisis , Titanio/análisis , Temperatura , Óxido Ferrosoférrico , Iluminación , Bacterias , Contaminantes del Suelo/análisisAsunto(s)
Contaminantes del Suelo , Vanadio , Vanadio/análisis , Suelo , Plantas , Contaminantes del Suelo/análisisRESUMEN
As an important commercial form of vanadium, vanadium pentoxide (V2O5) is widely used in various modern industries, and its environmental impacts and ecotoxicity have been extensively studied. In this research, the ecotoxicity of V2O5 to earthworms (Eisenia fetida) in soil was tested by exposure to V2O5 at a series of doses, and biochemical response indices, such as the superoxide dismutase (SOD) and catalase (CAT) enzyme activity and malondialdehyde (MDA) content, were analysed to determine the mechanism by which antioxidant enzymes respond to V2O5 exposure. The bioaccumulation factor (BAF) of vanadium pentoxide in the earthworms and soil was also measured to explore the bioaccumulation process of V2O5 in the test period. The results showed that the acute and subchronic lethal toxicity values of V2O5 towards E. fetida were 21.96 mg/kg (LC50, 14 days) and 6.28 mg/kg (LC10, 28 days), respectively. For the antioxidant enzymes, SOD and CAT were synchronously induced or inhibited within the time period, and the enzyme activity had a dose-effect relationship with the V2O5 concentration. MDA analysis indicated that lipid peroxidation in earthworms mainly occurred at the early stage and was eliminated slowly in the later stage during the test time. In addition, the BAFs were much less than 1, which indicated that V2O5 did not easily accumulate in earthworms, and the BAF was positively correlated with the exposure time and negatively linearly correlated with the V2O5 concentration in the soil. These results indicated that the bioconcentration and metabolic mechanism of V2O5 in earthworms differed with the different exposure concentrations, and bioaccumulation became balanced after 14-28 days in earthworms exposed to a relatively lower dose of V2O5. The analysis of the integrated biomarker response (IBR) index indicated that the trends of IBR values were positively related to the changing V2O5 concentration, and the IBR index could reflect the organism's sensitivity to the external stimulus of V2O5. The toxicity of V2O5 is mainly caused by V5+, which is also an important factor in formulating guidelines regarding vanadium levels in soil, and the test earthworm species (Eisenia fetida) is a sensitive biological indicator for risk assessments of vanadium oxidation in the soil.