We present the case of a 59 year old female with history of severe neurologic dysfunction from advanced multiple sclerosis who presented with lethargy and oliguria several hours after urethral Foley ...catheterization. A contrast-enhanced CT scan of the abdomen/pelvis showed an aberrantly placed Foley catheter with its balloon inflated in the proximal left ureter, a rare complication of Foley catheterization with only 5 other cases reported. Incomplete ureteral rupture was demonstrated and confirmed by a followup CT scan in the urographic phase. One of our institution's Interventional Radiologists then placed a nephroureteral stent across the injured ureter to facilitate healing. The patient expired 9 days after the procedure from unrelated sepsis from a chronic stage IV decubitus ulcer, so long term monitoring could not be performed. Following description of our case, we conduct a literature review of presentations, imaging characteristics, and treatment of ureteral Foley catheter placement.
Although extraintestinal manifestations of inflammatory bowel disease (IBD) are common, pulmonary IBD is extremely rare. Owing to its nonspecific clinical, radiologic, and pathologic features, ...pulmonary IBD is difficult to diagnose and may mimic more concerning disease processes. We present a rare case of a patient with known Crohn's disease whose initial presentation was highly suspicious for malignancy before further investigation revealed pulmonary IBD.
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•Arsenic behaviour in naturally As-enriched agricultural soils was investigated.•Arsenic content was high in clay fraction and low in silt fraction.•Significant portion of ...non-specifically sorbed As was released from silt and sand.•Well-crystalline Fe- and Al-oxide bound As was highest in silt and clay fractions.•Arsenolite (AsIII) and scorodite (AsV) were identified as the dominant As minerals.
Naturally arsenic (As) enriched agricultural soils represent a significant global human health risk. In this study, As fractionation and mineralogy were investigated in naturally As-enriched agricultural soils and their corresponding sand, silt and clay fractions. Median As increased generally in the order (mg/kg)∶ silt (280) < bulk (314) < sand (323)<clay (484). Sequential extraction showed that amorphous and well-crystalline Fe- and Al-oxide bound and residual As forms accounted 27-42% of total As. Well-crystalline Fe- and Al-oxide bound As was highest (40-42%) in silt and clay fractions, while residual As was generally greatest (41-55%) in bulk and sand fractions. The sand, silt and bulk soils released a consistently higher percentage of non-specifically sorbed As than the clay, but clay released more specifically-sorbed As. Arsenate (As(V)) was the dominant species in soil solutions, although arsenite (As(III)) was significant in a few samples. XRD analysis showed the presence of arsenolite (As2IIIO3) in soils and fractions. SEM/EDS observations revealed that scorodite (FeAsVO4·2H2O) and amorphous Fe-oxides were the main As-bearing minerals in soils and fractions, which were consistent with the geochemical analysis. Outcomes from this research highlight the significant environmental risks of naturally As-enriched soils.
A novel biochar metal oxide composite was synthesized for effective removal of arsenate (As(V)) from aqueous solution. The materials synthesized for As(V) removal was based on a biosolid-derived ...biochar (BSBC) impregnated with zirconium (Zr) and zirconium-iron (Zr-Fe). The synthesized materials were comprehensively characterized with a range of techniques including Brunauer–Emmett–Teller (BET-N2) surface area, zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results confirmed that loading of Zr and Zr-Fe onto the biochar surface was successful. The influence of pH, biochar density, ionic strength, As(V) dose rate, major anions and cations on As(V) removal was also investigated. Under all pH and reaction conditions the Zr-Fe composite biochar removed the greatest As(V) from solution of the materials tested. The maximum sorption capacity reached 15.2 mg/g for pristine BSBC (pH 4.0), while modified Zr-BSBC and Zr-FeBSBC composites achieved 33.1 and 62.5 mg/g (pH 6), respectively. The thermodynamic parameters (Gibbs free energy, enthalpy, and entropy) suggested that the adsorption process is spontaneous and endothermic. The ZrBSBC and Zr-FeBSBC showed excellent reusability and stability over four cycles. Unmodified biochar resulted in partial reduction of As(V) under oxic conditions, whilst modified biochars did not influence the oxidation state of As. All results demonstrated that the Zr and Zr-Fe BSBC composites could perform as promising adsorbents for efficient arsenate removal from natural waters.
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•Novel Zr-O and Zr-O-Fe impregnated biochars composites were synthesized for arsenate removal.•SEM and TEM results confirmed Zr-O and Zr-O-Fe impregnation onto biochar.•The maximum sorption capacity reached to 62.5 mg/g for Zr-Fe biochar composite.•Removal of arsenate was greater under acidic conditions.
Arsenic contamination in abandoned soils is a global concern which warrants an effective method of remediation. In this study, two organic acids and one biodegradable chelating agent were used to ...treat arsenic (As) contaminated abandoned mine soils. The concentration of As was 19,100 and 75,350 (mg/kg) for Webbs Consols (WC) and Mole River (MR) samples, respectively. X-ray diffraction and scanning electron microscopy confirmed that tooeleite, arsenopyrite, scorodite and quartz were the major minerals in these soils. A major portion of the As was composed of amorphous and crystalline oxides of Fe and Al determined by sequential extraction. Among the three washing reagents (oxalic acid, citric acid and EDDS) oxalic acid showed the best performance for extracting As. Based on the batch experiment, 0.5 M oxalic acid and 3 h of washing was the most efficient treatment to extract As and other trace elements. Extraction of As, Fe, and Pb was 70, 55, and 48% respectively for WC, while 68, 45 and 63% respectively for MR soil. Oxalic acid extracted 75 and 83% of As and Fe, respectively from tooeleite. Leachability and bioaccessibility of As and Fe in the treated soil was reduced due to washing. However, bioaccessibility and leachability of Pb in soil and Fe and As in tooeleite increased in washed samples. Though the leachability and bioaccessibility of As and Fe in soil was reduced in the treated soil, As still exceeded the USEPA criteria (5 mg/L) which is needed to successfully remediate soil by washing. Soil washing and subsequent solidification/stabilization could be an alternative option to remediate extremely contaminated abandoned mine soil.
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•Oxalic acid was efficient in extracting As and other trace elements in abandoned mine soils.•Extraction of As and other trace elements increased with increasing Fe extraction.•Bioaccessibility and leachability of As was reduced after soil washing.
Understanding the transport behaviour of arsenic (As) from soils to humans is critical when undertaking human health risk assessment and contamination control. This research examined As ...bioaccessibility in different As fractions and particle size fractions of As-enriched mine soils using different extractions. Bioaccessibility of As ranged from 0.24% to 32% for Solubility Bioaccessibility Research Consortium (SBRC) and Physiologically Based Extraction Test (PBET) methods, with extractable As (using 0.43 M HNO3) being 1.3–24.9%. The highest As bioaccessibility (19–32%) was consistently observed in the fine particle size fraction (< 53 µm) of all three extractions. Sequential extractions revealed that As fractions were mostly associated with crystalline (30–73%) and amorphous (9–59%) Fe/Al oxyhydroxides. The bioaccessibility of As in the gastric phase of SBRC and PBET methods highlighted a positive correlation (R2 = 0.83–0.88, p < 0.01) with exchangeable, surface and amorphous- bound As fractions, while the intestinal phase showed a strong positive correlation (R2 = 0.85–0.89, p < 0.01) with exchangeable and surface bound fractions. The study revealed that As bioaccessibility in soils can potentially be determined using the 0.43 M HNO3 extraction procedure. Health risk assessment confirmed that there was a strong increase in chronic daily intake, hazard quotient and cancer risk, with a reduction in particle size.
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•Bioaccessibility of As in abandoned mine soils varied between 0.24% and 32%.•Exchangeable and surface-bound As fractions mainly contributed to bioaccessible As.•Arsenic extracted by 0.43 M HNO3 correlated with other in-vitro digestion methods.•Fine particles (< 53 µm) have higher bioaccessibility and pose potential health risk.
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•A comprehensive investigation of As distribution was conducted in soils from abandoned mine sites.•Particle size distribution of trace elements in mine site soil was not ...homogeneous.•Both fine and coarse particle fractions have elevated levels of As, Sb, Pb and Zn.•XRD, SEM and TEM analyses show tooeleite and scorodite are the predominant As minerals in mine soils.•Arsenic distribution in mine soils is strongly associated with crystalline and amorphous Fe phases.
Trace element contamination from abandoned mine sites is a major threat to the environment. The distribution of trace elements in various particle size fractions of soils from abandoned mine sites plays a critical role in designing remediation approaches. This study investigated the geochemical distribution of trace element enrichment and mineralogical composition in various particle size fractions from contrasting abandoned mine sites (Webbs Consols, Halls Peak and Mole River, Australia). Results revealed that arsenic and other element concentrations increased with decreasing particle size for samples from Webbs Consols and Halls Peak. The highest arsenic (3.05%), lead (3.23%) and zinc (1110 mg/kg) were found in the finest fraction (<0.053 mm). In Mole River, the highest concentration of arsenic (10.8%), lead (209 mg/kg) and zinc (351 mg/kg) were observed in coarse fractions. Arsenic fractionation by sequential extraction showed that arsenic was strongly associated with the amorphous and crystalline iron phases. X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies revealed that tooeleite (a ferric arsenite mineral, also confirmed by Transmission electron microscopy (TEM)), arsenopyrite, scorodite and arsenolite were the dominant arsenic minerals. The study showed elevated levels of arsenic bearing minerals across particle sizes which has significant implications for remediation approaches at abandoned mine sites.
At abandoned mine sites, arsenic (As)- and antimony (Sb)-enriched soils are often disposed of through onsite burial or capping. In highly weathered mine sites, the mobility of As and Sb is typically ...controlled by iron (Fe)(III)/Fe(II) phases; thus, the suitability of such disposal methods and appropriate testing techniques are questionable. In the present study, leaching potentials of As and Sb were examined using the toxicity characteristic leaching procedure (TCLP), waste extraction test (WET), and WET-extended procedure (WET-EXT) at three abandoned mine site soils in Australia. The leached concentration of As regularly exceeded USEPA criteria (5 mg L−1). The highest leached concentrations of As and Sb were observed in the finest particle size fraction (< 0.053 mm) by WET-EXT (1 040 mg L−1 for As and 21.10 mg L−1 for Sb) followed by WET (800 mg L−1 for As and 20.90 mg L−1 for Sb). The TCLP method resulted in the lowest concentrations of leached As (0.000 9 mg L−1) and Sb (0.000 3 mg L−1). Crystalline and amorphous As-bearing Fe oxides were the main phases in the soils studied. However, the best correlations of leached As determined by TCLP (0.832), WET (0.944), and WET-EXT (0.961) were found with the non-specifically sorbed (NS1) As fraction. The mineralogical and sequential extraction data clearly indicate the dominant role of Fe geochemistry in controlling leachability of As and Sb. The TCLP method was unlikely to be suitable for assessing leachability, as it exhibited no relationship with leachable Fe and substantially lower leached As and Sb than the other two methods. Given the high to extremely high leachable As and Sb concentrations, most of the soil samples would not be recommended for placement in capping works, old shafts, or reduction systems (e.g., collection in drainage basins).
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