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The tanning industry is one of the largest environmental polluters due to high generation waste in all production processes, but the tanning is particularly worrisome due to the use of significant amounts of chromium. Cr is an element potentially toxic to both health and the environment, depending on the concentration and the oxidation state. Cr(VI) can come in contact with human skin when using leather goods, which can cause allergies and dermatitis, besides being carcinogenic. Considering that approximately 90% of the world production of leather is performed with Cr salts, the determination of this element in leather is necessary to avoid exposure to the risks that the element can provide. The main goal of this study was the development of an alternative analytical method for the determination of Cr in leathers (ovine and bovine leather tanned with Cr and vegetable tannin) using wavelength dispersive X-ray fluorescence (WDXRF) for direct solid analysis. Besides performing analysis of the chemical composition and determination of Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Ni, Pb, Sb, Sr, Ti, and Zn in leather by inductively coupled plasma optical emission spectrometry (ICP OES). Principal component analysis (PCA) was also used in the evaluation of the WDXRF and ICP OES data sets. WDXRF calibration models for Cr presented satisfactory figures of merit and the analysis of the leathers revealed an alarming concentration of total Cr in the samples reaching 21,353 mg kg -1 .

Synthetic leather samples from Brazil and Paraguay were evaluated in this study using three spectroscopy techniques: inductively coupled plasma optical emission spectrometry (ICP-OES), laser-induced breakdown spectroscopy (LIBS), and wavelength dispersive X-ray fluorescence (WDXRF). The obtained information from each technique was separately inspected with principal component analysis (PCA). The concentrations of the elements determined in the synthetic leathers using ICP-OES decreased in the following order: Ca > Cr > Mg > Ba > Pb > Al > Fe > Zn > Sb > Ni with a concentration range below the limit of quantification (-1 (case of Ca). Additionally, Cu, As, Sr, Ti, Cd, Mn, Co, and Ni were present in only few samples in a concentration range from -1 . Principal component analysis was the tool used to evaluate the samples from their chemical content obtained quantitatively using ICP-OES and qualitatively using LIBS or WDXRF spectra. The results showed that the association of PCA with spectroscopic techniques was satisfactory for data inspection of synthetic leathers according to the chemical composition. Laser-induced breakdown spectroscopy and WDXRF were able to identify the presence of toxic elements like Cr (LIBS and WDXRF) and Pb (WDXRF).

The former mine of Escádia Grande was active at the middle of 1900 and was exploited for Au and Ag. The mineralized quartz veins consist mainly of quartz, arsenopyrite, pyrite, rare chalcopyrite, galena, sphalerite, gold and argentite. The mine dumps and tailings were deposited close to a stream, and there is a river beach downstream used for recreational proposes. Two villages are also located close to the old mining area. Mine wastes contained up to 8090 mg/kg of As and 70.1 mg/kg of Sb. The waters of the stream that cross the mining area have circum-neutral pH values and contained elevated concentrations of As reaching up to 284 µg/L. However, geochemical speciation modeling (Phreeq C) revealed that As was mainly present as As (V). Arsenic concentrations in waters are attenuated throughout the stream, mainly by the iron-(hydro)-oxides adsorption upstream. However, at 2 km downstream of mine wastes in the river beach, the waters still exceeded 10 µg/L of As, the drinking water limit. The waters also have NO 2 - , Cu and Cd concentrations higher than drinking water limit. The stream sediments have As concentrations up to 45 times higher (3140 mg/kg) than the limit of the sediment guideline values of NWQMS (2000). The maximum arsenic concentrations in soils are also up to 27 times higher (5940 mg/kg) than the maximum concentrations in streams from FOREGS Geochemical Atlas of Europe. The use of river beach for recreational purposes causes cancer risk (4.48 × 10 -6 ) higher than USEPA limit, mainly due to the arsenic exposure. Even for recreational purposes, stream sediments and soils in the old mining area have high non-carcinogenic effects (2.76 and 4.78, respectively) for children, also related to the arsenic exposure mainly by the ingestion pathway, and the risk is unacceptable according to the limits of USEPA. Moreover, the cancer risk resulting from exposure of adults to arsenic in soils also has unacceptable non-cancer risk (1.13). Arsenic is the main trace element that causes a human health concern in the Escádia Grande mining area.

The mining complex of Murçós belongs to the Terras de Cavaleiros Geopark, located in Trás-os-Montes region, northeast Portugal. A stockwork of NW-SE-trending W>Sn quartz veins intruded Silurian metamorphic rocks and a Variscan biotite granite. The mineralized veins contain mainly quartz, cassiterite, wolframite, scheelite, arsenopyrite, pyrite, sphalerite, chalcopyrite, galena, rare pyrrhotite, stannite, native bismuth and also later bismuthinite, matildite, joseite, roosveltite, anglesite, scorodite, zavaritskite and covellite. The exploitation produced 335t of a concentrate with 70% of W and 150t of another concentrate with 70% of Sn between 1948 and 1976. The exploitation took place mainly in four open pit mines as well as underground. Three lakes were left in the area. Remediation processes of confination and control of tailings and rejected materials and phytoremediation with macrophytes from three lakes were carried out between 2005 and 2007. Stream sediments, soils and water samples were collected in 2008 and 2009, after the remediation process. Most stream sediments showed deficiency or minimum enrichment for metals. The sequential enrichment factor in stream sediments W>Bi>As>U>Cd>Sn=Ag>Cu>Sb>Pb>Be>Zn is mainly associated with the W>Sn mineralizations. Stream sediments receiving drainage of a mine dump were found to be significantly to extremely enriched with W, while stream sediments and soils were found to be contaminated with As. Two soil samples collected around mine dumps and an open pit lake were also found to be contaminated with U. The waters from the Murçós W>Sn mine area were acidic to neutral. After the remediation, the surface waters were contaminated with F(-), Al, As, Mn and Ni and must not be used for human consumption, while open pit lake waters must also not be used for agriculture because of contamination with F(-), Al, Mn and Ni. In most waters, the As occurred as As (III), which is toxic and is easily mobilized in the drainage system. The remediation promoted a decrease in metals and As concentrations of soils and waters, however the applied processes were not enough to rehabilitate the area., (Copyright © 2016 Elsevier Inc. All rights reserved.)

This case report shows the clinical development of a patient with systemic paracoccidioidomycosis presenting with lymphatic-intestinalmanifestation. The patient initially had a substantial clinical improvement but had a recrudescence after six months of sulfamethoxazoletrimethoprim oral treatment, with the emergence of feverish syndrome, lumbar pain, and intermittent claudication, characterizing a bilateral iliopsoas muscle abscess, necessitating clinicosurgical therapeutics.

The potential impact of the hepatitis C virus (HCV) on clinical, immunological and virological responses to initial highly active antiretroviral therapy (HAART) of patients infected with human immunodeficiency virus (HIV) is important to evaluate due to the high prevalence of HIV-HCV coinfection. A historical cohort study was conducted among 824 HIV-infected patients starting HAART at a public referral service in Belo Horizonte, Brazil, to assess the impact of HCV seropositivity on appearance of a new AIDS-defining opportunistic illness, AIDS-related death, suppression of viral load, and an increase in CD4-cell count. A total of 76 patients (9.2%) had a positive HCV test, 26 of whom (34.2%) had a history of intravenous drug use. In multivariate analysis, HCV seropositivity was associated with a smaller CD4-cell recovery (RH=0.68; 95% CI [0.49-0.92], but not with progression to a new AIDS-defining opportunistic illness or to AIDS-related death (RH=1.08; 95% CI [0.66-1.77]), nor to suppression of HIV-1 viral load (RH=0.81; 95% CI [0.56-1.17]) after starting HAART. These results indicate that although associated with a blunted CD4-cell recovery, HCV coinfection did not affect the morbidity or mortality related to AIDS or the virological response to initial HAART.