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To estimate the impact of mercury released from an artisanal small-scale gold mining (ASGM) activities on the ecosystem. Total and organic mercury concentrations in paddy field soil and freshwater snails around an artisanal small-scale gold mining area were investigated. Paddy field soil samples and freshwater snails were collected from ten sites along the Cikaniki River. A site located in a national park, which was approximately 12 km upstream from the ASGM site, was considered the reference site for this study. The organic mercury concentration in soil samples collected at the ASGM site was n.d.–0.018 mg kg−1 and that at the reference site was 0.005–0.008 mg kg−1. The organic mercury concentrations in the freshwater snails collected at the ASGM and reference sites were 0.38 ± 0.21 mg kg−1 (31.0 ± 26.6% of total mercury, n = 38) and 0.056 ± 0.032 mg kg−1 (40.5 ± 11.5% of total mercury, n = 16), respectively. Although the original form of mercury in the mining waste was elemental mercury and/or Hg2+, the mercury form changed to organic mercury in environment and the organic mercury was concentrated two orders of magnitude, even in low-order organisms.

This study was conducted to understand the environmental behavior of mercury released by artisanal and small-scale gold mining (ASGM) activities. For this purpose, we attempted to assess the effect of diffused mercury on mercury concentrations in soil, demonstrate the presence of methylmercury in soil affected by the deposited mercury and determine the reactions associated with methylmercury production. The vertical profiles of mercury were obtained from two sites in the forest of the ASGM village in Pongkor (West Java, Indonesia) and from two sites in Mount Halimun-Salak National Park, which is approximately 12 km from the ASGM village. The highest total mercury concentration, 8.9 mg kg−1, was observed for soil samples collected at the ASGM village. The mercury was concentrated at the surface or in the subsurface layers, and the concentrations were several times to more than ten times higher than the lowest values observed in the deeper layers at each site. Even in the national park, the highest concentration of 1.9 mg kg−1 was observed in the upper soil layer. These results suggest that the primary source of mercury in the forest soil is atmospheric deposition; fallen plant leaves also deliver accumulated mercury to the soil surface. The organic mercury percentages of the total mercury were 0.2 ± 0.1% for the national park and 0.3 ± 0.2% for ASGM sites. The vertical variation in organic mercury concentration did not always match that in total mercury concentration, which suggested that the formation of methylmercury in soil was closely related to the decomposition of organic matter near the surface. The soil surface is an important reaction field for methylmercury production in forested areas.

To evaluate the impact of mercury released into a river system by artisanal and small-scale gold mining (ASGM) activity in West Java, Indonesia, the temporal variations in elemental mercury, mercury ions, dissolved total mercury and particulate mercury concentrations in river water were observed in March 2015 (rainy season) and August 2015 (dry season) at a fixed observation point, and the migrated amount of mercury was estimated. Variations for other metals, total organic carbon (TOC), and total nitrogen (TN) contents were also measured. There have been few reports in which the amount of mercury transferred from ASGM activities is quantitatively estimated, and this study provides important data for evaluating the environmental impact of mercury released by ASGM activities. The concentration of filtered total mercury and the particulate mercury concentration observed in the dry season were 161 ± 167 μg L−1 and 142 ± 93 μg L−1, respectively, and these values were significantly higher than the values of 24.5 ± 23.9 μg L−1 and 53.7 ± 44 μg L−1 for filtered total mercury and particulate mercury, respectively, observed in the rainy season. On the other hand, the river flow in the rainy and dry seasons was 2.6 × 104 ± 5×103 m3 h−1 and 8.2 × 103 ± 8×102 m3 h−1, respectively, and an apparent increase in the amount of water in the rainy season was observed. The transfer amounts in the rainy and dry seasons obtained from these results were 6.2 × 102 ± 6.7 × 102 g h−1 and 1.6 × 103 ± 1.6 × 103 g h−1, respectively, for filtered total mercury and 1.3 × 103 ± 1.3 × 103 g h−1 and 1.1 × 103 ± 7×102 g h−1, respectively, for particulate mercury. The temporal variations in these values exhibited a wide range, indicating the effects of weather conditions and of the mining process.

To estimate the impact of mercury discharged from artisanal and small-scale gold mining (ASGM) activity, variations in the concentrations of elemental mercury (Hg0), mercury ion (Hg2+), particulate mercury (P-Hg), and total mercury in filtered river water (FT-Hg) were investigated from sampling locations extending from 10 km upstream to 30 km downstream of ASGM operations in West Java, Indonesia. The average of the annual concentrations at the ASGM site from 2013 to 2017 were 0.14–0.85 μg L−1, 0.27–12.9 μg L−1, 4.3–49.5 μg L−1, and 1.2–12.5 μg L−1 for Hg0, Hg2+, P-Hg, and FT-Hg, respectively. The concentration of mercury species decreased as the distance from the ASGM site increased, while the ratio of P-Hg increased towards the lower reaches of the river system, with the percentage of P-Hg estimated at 90% of Hg at the sample location furthest downstream. A high mercury concentration of 600 mg kg−1 was observed for suspended particulate matter (SPM) at the ASGM site. The SPM maintained a high concentration of mercury, even in the downstream area. In the annual variations of the mercury species from 2013 to 2017, FT-Hg and P-Hg concentrations tended to decrease from 2016, which suggested a decline of ASGM activity in this area. However, SPM and river sediment showed no apparent changes in their mercury concentrations over this period, indicating that the contamination in the river system is persistent and does not recover quickly.

Submarine fumaroles are located in the 200-m deep basin of the northern part of Kagoshima Bay. To estimate the influence of mercury emitted from these fumaroles, the seasonal changes in total mercury (T-Hg), reactive mercury (RM), dissolved gaseous mercury (DGM), and monomethylmercury (MMHg) in water were studied. Seawater samples were collected from five separate locations in the northern part from May, 2011 to May, 2012 using a CTD-Rosette water sampler; the samples were taken every 50 m, starting from the surface. T-Hg, DGM, RM, and MMHg in the seawater columns (n = 132) were in the range of 0.05–3.04 ng L − 1 , 0.003–1.08 ng L − 1 , 0.006–1.47 ng L − 1 , 0.02–0.69 ng L − 1 for an entire sample. Although the average T-Hg values at the surface and middle layers (0–100 m) for each sample showed no significant seasonal variation throughout the year, those at the deeper layer (150–200 m) were high from summer to autumn and low in winter. The seasonal changes and vertical distributions of DGM, RM, and MMHg concentrations were similar to those of T-Hg. A thermocline was observed from spring to autumn and ceased in winter. Because the thermocline prohibits vertical circulation of seawater, the fumarole impact may increase during those months.

Copyright © 2015 by The Geochemical Society of Japan. mercury in seawater can be an indicator of widespread underwater mineral deposits (Marumo et al., 2008; Tomiyasu et al., 2007). Therefore, deep-sea mercury monitoring is very important to both the caution of environmental pollution and the exploration of underwater mineral deposits. Due to their high sensitivity, cold vapor atomic absorption spectrometry (CV-AAS) (Chakraborty et al., 2014a, c), cold vapor atomic fluorescence spectrometry (CV-AFS) (Fernandez-Martinez et al., 2015), and inductively coupled plasma mass spectrometry (ICP-MS) (Baya et al., 2015) have been the most commonly used for the measurement of total mercury. All of these techniques require expensive and sophisticated instrumentation combined with complicated sample preparation processes (Chakraborty et al., 2015; Ferreira et al., 2015; Giacomino et al., 2008). Sample collection needs certain spatial and temporal resolutions of the target fields, and there is a risk of contamination and/or loss of mercury during the sampling and transfer of water from depth to the surface Development of a deep-sea mercury sensor using in situ anodic stripping voltammetry

To estimate the current contamination levels in Minamata Bay, the vertical and horizontal distributions of mercury in the sediment were investigated. Sediment core samples were collected in 2002, 2006, 2008, and 2010 at 12 locations by gravity core sampling in Minamata Bay and Fukuro Bay, which is located in the southern part of Minamata Bay. The average total mercury concentrations during each year in the surface sediment were 2.47–3.34 and 3.50–4.66 mg kg − 1 for Minamata Bay and Fukuro Bay, respectively; significant variation in the values was not observed during the study period. The total mercury concentration in Fukuro Bay increased with increasing depth and reached a maximum at 8–14 cm from the surface and decreased with increasing depth in the deeper layer. In Minamata Bay, the total mercury concentration did not change significantly from the surface to a depth of 10 cm and the values were considerably higher than the background level. In the lower layers of the long cores taken from both areas, the total mercury concentration decreased with depth, and the deepest layers exhibited relatively uniform low values. These values can be considered to represent the background concentration in the absence of anthropogenic influence. The depth of the sediment affected by the effluent was estimated to be 20 ± 7 cm and 33 ± 4 cm for Minamata Bay and Fukuro Bay, respectively. Furthermore, it was estimated from the average concentration and volume of the contaminated layer that approximately 1 ton of discharged mercury remained in the sediment of the two bays.

The distribution of mercury in the soil, sediment and river water around the artisanal small-scale gold mining (ASGM) area along the Cikaniki River, West Java, Indonesia, was investigated. The total mercury concentration (T-Hg) in the forest soil ranged from 0.11 to 7.0mgkg(-1), and the highest value was observed at the ASGM village. In the vertical T-Hg profile around the villages, the highest value was observed at the soil surface, and the concentration decreased with depth. This result suggested that the mercury released by mining activity was dispersed through the atmosphere and deposited on the surface. The total organic carbon content (TOC) showed a similar vertical profile as the T-Hg, and a linear relationship was found between T-Hg and TOC. Mercury deposited on the surface can be absorbed by organic matter. The slope of the line was larger near the ASGM village, implying a higher rate of deposition of mercury. The T-Hg in the sediment ranged from 10 to 70mgkg(-1), decreasing gradually toward the lower reaches of the river. Mining waste can be transported with the river flow and deposited along the river. The distribution of the mining waste can be determined using the mineralogical composition measured by X-ray fluorescence spectrometry.

Background Many patients who have lower-extremity amputations secondary to peripheral vascular disease or diabetes require reamputation eventually. This study was designed to identify the incidence of and risk factors for ipsilateral reamputation after forefoot amputation, to evaluate whether postoperative infection increases the risk of reamputation, and to evaluate whether the risk of reamputation was reduced by the duration of antimicrobial therapy after amputation. Methods A retrospective analysis of patients who underwent foot amputation for nontraumatic reason from January 2002 to December 2004 at the Veterans Affairs Pittsburgh Healthcare System was performed. Results Among 116 patients, 57 (49.1%) had ipsilateral reamputation within 3 years after their first surgeries; 78.9% received reamputation in the first 6 months; 53 (45.7%) died within 3 years; and 16 (13.8%) developed postoperative infections. Upper level of amputation, long duration of hospitalization, insulin-dependent diabetes, and gangrene on physical examination on admission were risk factors for reamputation in univariate analysis. Gangrene (odds ratio: 3.81, 95% confidence interval: 1.60–9.12, P = 0.003) and insulin-dependent diabetes (odds ratio: 2.93, 95% confidence interval: 1.26–6.78, P = 0.012) were risk factors in multivariate analysis. Postoperative infection did not increase the risk of reamputation. Longer than 2-week course of antibiotic use after amputation did not prevent reamputation. Conclusions Approximately one-half of patients required ipsilateral reamputation and died in 3 years. Gangrene on admission and history of insulin-dependent diabetes were significant risk factors (P = 0.003, P = 0.028). Long duration of antibiotic use after amputation and postoperative infection did not change the risk of reamputation.

This study investigates the distribution of total mercury (T-Hg) and methylmercury (MeHg) in the soil and water around the artisanal and small-scale gold mining (ASGM) area along the Cikaniki River, West Java, Indonesia. The concentration of T-Hg and MeHg in the forest soil ranged from 0.07 to 16.7 mg kg−1 and from

A sensitive determination method for mercury speciation analysis was developed. Four mercury species, mercury ion, methylmercury, ethylmercury, and phenylmercury, were complexed with emetine-dithiocarbamate (emetine-CS(2)), and then injected onto a HPLC instrument coupled with a tris(2,2'-bipyridine)ruthenium(III) chemiluminescence detection system. The emetine-CS(2) complexing agent was effectively used to measure the concentration in addition to serving as a separation and detection reagent. The calibration curves for these mercury complexes were linear in the range of 0.050 - 10 μg L(-1) (as Hg). The limit of detection for (emetine-CS(2))(2)Hg, emetine-CS(2)-methylmercury, emetine-CS(2)-ethylmercury, and emetine-CS(2)-phenylmercury were 30, 17, 21, and 22 ng L(-1), respectively. The sensitivity of this method enables the determination of mercury species in water samples at sub-ppb levels. Furthermore, the method was applied to biological samples in combination with acid leaching and liquid-liquid extraction using emetine-CS(2) as an extraction reagent. The determination results were in good agreement with the values of the certified reference materials.

A sensitive method for simultaneous determination of organic and inorganic mercury species has been developed and is presented in this study. The method is based on complex formation of mercury species with the emetine dithiocarbamate (emetine-CS2) ligand, HPLC separation, and tris(2,2′-bipyridine)ruthenium(III) chemiluminescence detection. The complexation reactions of the mercury species and emetine-CS2 ligand occurred instantaneously upon the addition of emetine-CS2 solution to the solution containing the mercury species. The complete separation of these complexes was achieved using an ODS column with 20 mM NaH2PO4-acetonitrile (52:48, v/v) containing 30 mM NaClO4 as an ion-pair reagent. The calibration graphs of these complexes were linear in the range from 1–100 µg/L. The detection limits were 0.27 µg/L, 0.33 µg/L, 0.39 µg/L, and 0.17 µg/L for methylmercury, ethylmercury, phenylmercury, and the mercury ion, respectively, at a signal-to-noise ratio of 3. The developed technique was validated by analyz...

中国雲南省个旧市老厂鎮及びKa fang zhenのスズ鉱山周辺で採取された土壌，河川底質試料に対し，混酸を用いた酸化分解処理を行い，水素化物発生原子吸光光度法を用いて総ヒ素濃度を測定した．また，波長分散型蛍光X線分析装置（WDXRF）を用いて土壌，底質試料の化学成分分析を行い，ヒ素を含む尾鉱の拡散について考察を行った．採取された試料中ヒ素濃度は5.1×102～1.1×104 mg kg－1であり，最も高い値を示したのは尾鉱ダム堆積物であったが，ダム周辺の畑土壌は5.1×102～4.5×103 mg kg－1，調査地の中心部を流れる河川底質は1.5×103～6.5×103 mg kg－1のヒ素を含んでおり，スズ鉱山活動の影響が周辺へ広がっていることが示された．日本におけるヒ素の土壌含有量基準は150 mg kg－1以下とされているが，本研究対象地域において確認された土壌の総ヒ素濃度は，その約3～30倍であった．WDXRFの分析結果から，尾鉱は主要成分の一つとして鉄を含んでいること，さらに，Fe2O3（％）とSiO2（％）の間には，有意な負の相関があることが分かった．このFe2O3（％）とSiO2（％）の存在比は尾鉱と周辺土壌との混合に対応すると考えられ，尾鉱の拡散を示す指標となり得ることが示された．さらに，尾鉱の化学的風化に伴ってヒ素も溶脱し，水系へと移行している可能性が示唆された．

大阪府池田市, 豊能町における平成14年度老人保健法に基づく健康診査のHCV検診の現況を報告する. 本地域において平成14年度に3478名 (男性1067名, 女性2411名) がHCV抗体検査を受けた. 受診者の68%が60歳以上であった. HCV抗体陽性率は3.48%で,HCV抗体陽性者121名中69名 (57.0%) がHCVキャリアと考えられた. HCVキャリア率は1.98% (男2.72%, 女1.66%) で, 男女とも加齢に伴い上昇した. 節目, 節目外検診受診者のHCVキャリア率はそれぞれ0.77%, 3.32%と節目外検診受診者で高率であった. HCVキャリア69名中24名 (34.8%) が市立池田病院を紹介され受診した. 受診者24名中ALT 35IU/l以上は13名で, 血小板は9名が15×104/μl未満であった. 現在4名がIFN治療を受けている. 肝細胞癌は発見されていない. 今回の検討から, HCV抗体検査の一般住民検診への導入は, HCVキャリアの発見に有用であると考えられた. また, 新規発見のC型肝炎患者には高齢者, ALT正常者が多く, これらの患者に対するIFN治療の適応に関する検討が重要と考えられた.

Guillain-Barre Syndrome (GBS) is a prototype of post-infectious autoimmune disease. A 76-year-old woman was treated for a renal abscess and developed muscle weakness in all four extremities, 18 days after the onset of infection. She was diagnosed with GBS on the basis of acute flaccid paralysis, hyporeflexia, nerve conduction studies (reduced amplitude of compound muscle action potentials), and high titers of IgG antibodies to GM1 and GalNAc-GD1a. GBS rarely occurs after sepsis and this case represents the first report of rapidly progressive GBS following Escherichia coli urosepsis.

Mercury pollution is caused by artisanal and small-scale gold mining (ASGM) operations along the Cikaniki River (West Java, Indonesia). The atmosphere is one of the primary media through which mercury can disperse. In this study, atmospheric mercury levels are estimated using the native epiphytic fern Asplenium nidus complex (A. nidus) as a biomonitor; these estimates shed light on the atmospheric dispersion of mercury released during mining. Samples were collected from 8 sites along the Cikaniki Basin during September-November, 2008 and September-November, 2009. The A. nidus fronds that were attached to tree trunks 1-3m above the ground were collected and measured for total mercury concentration using cold vapor atomic absorption spectrometry (CVAAS) after acid-digestion. The atmospheric mercury was collected using porous gold collectors, and the concentrations were determined using double-amalgam CVAAS. The highest atmospheric mercury concentration, 1.8 × 10(3) ± 1.6 × 10(3) ngm(-3), was observed at the mining hot spot, and the lowest concentration of mercury, 5.6 ± 2.0 ngm(-3), was observed at the remote site from the Cikaniki River in 2009. The mercury concentrations in A. nidus were higher at the mining village (5.4 × 10(3) ± 1.6 × 10(3) ngg(-1)) than at the remote site (70 ± 30 ngg(-1)). The distribution of mercury in A. nidus was similar to that in the atmosphere; a significant correlation was observed between the mercury concentrations in the air and in A. nidus (r=0.895, P

Background.Endonasal endoscopic skull base surgery (ESBS) is perceived as having a high risk of infection because it is performed through the sinuses, which are not sterile.Objective.To identify the bacteriological characteristics, incidence, mortality, and risk factors for intracranial infection after ESBS.Methods.A retrospective analysis of the first 1,000 ESBS procedures performed at the University of Pittsburgh Medical Center from 1998 to 2008.Results.In 18 cases (1.8%), the patient developed meningitis. In 2 cases, the patient died within 2 months after surgery, of noninfectious causes. In 11 cases, cerebrospinal fluid (CSF) cultures had positive results. There were no predominant pathogens. Male sex (odds ratio [OR], 3.97 [95% confidence interval {CI}, 1.21-13.03]; P = .02), history of a craniotomy or endonasal surgery (OR, 4.77 [95% CI, 1.68-13.56];P = .003), surgerywith higher levels of complexity (OR, 6.60 [95% CI, 1.77-24.70];P = .005), the presence of an external ventricular drain or ventriculoperitoneal shunt at the time of surgery (OR, 6.38 [95% CI, 1.07-38.09]; P = .04), and postoperative CSF leak (OR, 12.99 [95% CI, 4.24-39.82]; PConclusion.The incidence of infection of 1.8% in ESBS is comparable to that in open craniotomy. The most important risk factor was a postoperative CSF leak. All patients recovered from their infection.

The suitability of the epiphytic fern Lepisorus thunbergianus (Kaulf.) Ching, common in East and Southeast Asia, for the in situ biomonitoring of atmospheric mercury levels was investigated. L. thunbergianus is an evergreen fern with young, mature and old fronds throughout the year. Fertile mature fronds were used for the monitoring since the young fronds showed a high relative standard deviation (RSD) due to a shorter period of exposure, and the old fronds showed significantly high mercury concentrations with a slightly high RSD. When the mercury concentration in the fronds was plotted against the average mercury concentration in air, a significantly higher correlation was observed for the average value for the last 5-8 months. The regression equation y=13.6 x -1.4 was obtained, where "y" is the mercury concentration in the fronds (ng g(-1) dry mass (DM)) and "x" is the corresponding average concentration in ambient air (ng m(-3)). Atmospheric mercury levels can be estimated from the biomonitoring data: from the 95% confidence intervals, an atmospheric mercury concentration of 5 ng m(-3), estimated from a concentration of 70 ng g(-1) DM in fronds, corresponds to atmospheric mercury levels of between 3 and 8 ng m(-3).

Guillain-Barré Syndrome (GBS) is a prototype of post-infectious autoimmune disease. A 76-year-old woman was treated for a renal abscess and developed muscle weakness in all four extremities, 18 days after the onset of infection. She was diagnosed with GBS on the basis of acute flaccid paralysis, hyporeflexia, nerve conduction studies (reduced amplitude of compound muscle action potentials), and high titers of IgG antibodies to GM1 and GalNAc-GD1a. GBS rarely occurs after sepsis and this case represents the first report of rapidly progressive GBS following Escherichia coli urosepsis.