Health & Environmental Research Online (HERO)


Chromium VI

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The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Arsenic and chromium speciation in an urban contaminated soil

Authors: Landrot, G; Tappero, R; Webb, SM; Sparks, DL (In Press) Chemosphere. HERO ID: 1070401

[Less] The distribution and speciation of As and Cr in a contaminated soil were studied by synchrotron-based . . . [More] The distribution and speciation of As and Cr in a contaminated soil were studied by synchrotron-based X-ray microfluorescence (μ-XRF), microfocused X-ray absorption spectroscopy (μ-XAS), and bulk extended X-ray absorption fine structure spectroscopy (EXAFS). The soil was taken from a park in Wilmington, DE, which had been an important center for the leather tanning industry along the Atlantic seaboard of the United States, until the early 20th century. Soil concentrations of As, Cr, and Pb measured at certain locations in the park greatly exceeded the background levels of these heavy metals in the State of Delaware. Results show that Cr(III) and As(V) species are mainly present in the soil, with insignificant amounts of Cr(VI) and As(III). Micro-XRF maps show that Cr and Fe are distributed together in regions where their concentrations are diffuse, and at local spots where their concentrations are high. Iron oxides, which can reduce Cr(VI) to Cr(III), are present at some of these hot spots where Cr and Fe are highly concentrated. Arsenic is mainly associated with Al in the soil, and to a minor extent with Fe. Arsenate may be sorbed to aluminum oxides, which might have transformed after a long period of time into an As-Al precipitate phase, having a structure and chemical composition similar to mansfieldite (AlAsO(4)⋅2H(2)O). The latter hypothesis is supported by the fact that only a small amount of As present in the soil was desorbed using the characteristic toxicity leaching procedure tests. This suggests that As is immobilized in the soil.

Journal Article
Journal Article

High resolution micro arthrography of hard and soft tissues in a murine model

Authors: Gu, XI; Palacio-Mancheno, PE; Leong, DJ; Borisov, YA; Williams, E; Maldonado, N; Laudier, D; Majeska, RJ; Schaffler, MB; Sun, HB; Cardoso, L (In Press) . HERO ID: 1234051

[Less] OBJECTIVE: Recent developments on high resolution micro computed tomography (μCT) allow imaging of soft . . . [More] OBJECTIVE: Recent developments on high resolution micro computed tomography (μCT) allow imaging of soft tissues in small animal joints. Nevertheless, μCT images cannot distinguish soft tissues from synovial fluid due to their similar mass density, limiting the 3D assessment of soft tissues volume and thickness. This study aimed to evaluate a lead chromate contrast agent for μCΤ arthrography of rat knee joints ex vivo. DESIGN: Intact tibiofemoral rat joints were injected with the contrast agent at different concentrations and imaged using a μCT at 2.7 μm isotropic voxel size. Cartilage thickness was measured using an automated procedure, validated against histological measurements, and analyzed as a function of μCT image resolution. Changes in hard and soft tissues were also analyzed in tibiofemoral joints 4 weeks after surgical destabilization of the medial meniscus (DMM). RESULTS: The contrast agent diffused well throughout the whole knee cavity without penetrating the tissues, therefore providing high contrast at the boundaries between soft tissues and synovial fluid space. Thickness analysis of cartilage demonstrated a high similarity between histology and μ-arthrography approaches (R(2) = 0.90). Four weeks after surgical DMM, the development of osteophytes (Oph) and cartilage ulcerations was recognizable with μCT, as well as a slight increase in trabecular bone porosity, and decrease in trabecular thickness. CONCLUSIONS: A lead chromate-based contrast agent allowed discriminating the synovial fluid from soft tissues of intact knee joints, and thus made possible both qualitative and quantitative assessment of hard and soft tissues in both intact and DMM tibiofemoral joints using high resolution μCT.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Occupational allergic contact dermatitis and patch test results of leather workers at two Indonesian tanneries

Authors: Febriana, SA; Jungbauer, F; Soebono, H; Coenraads, PJ (In Press) Contact Dermatitis. HERO ID: 1234053

[Less] Background. Tannery workers are at considerable risk of developing occupational contact dermatitis. . . . [More] Background. Tannery workers are at considerable risk of developing occupational contact dermatitis. Occupational skin diseases in tannery workers in newly industrialized countries have been reported, but neither the prevalence of occupational allergic contact dermatitis nor the skin-sensitizing agents were specifically examined in those studies. Objectives. To assess the prevalence of occupational allergic contact dermatitis in Indonesian tanneries, identify the causative allergens, and propose a tannery work series of patch test allergens. Patients/methods A cross-sectional study in all workers at two Indonesian tanneries was performed to assess the prevalence of occupational contact dermatitis via a questionnaire-based interview and skin examination. Workers with occupational contact dermatitis were patch tested to identify the causative allergens. Results. Occupational contact dermatitis was suspected in 77 (16%) of the 472 workers. Thirteen (3%) of these 472 workers were confirmed to have occupational allergic contact dermatitis. Potassium dichromate (9.2%), N,N-diphenylguanidine (5.3%), benzidine (3.9%) and sodium metabisulfite (2.6%) were found to be the occupationally relevant sensitizers. Conclusions. The sensitization pattern showed some differences from the data in studies reported from other newly industrial countries. We compiled a 'tannery work series' of allergens for patch testing. A number of these allergens may also be considered for patch testing in patients with (leather) shoe dermatitis.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Zinc PVA versus potassium dichromate for preservation of microsporidian spores of human origin

Authors: El-Taweel, HA; Tolba, MM; Sadaka, HA; El-Zawawy, LA; Osman, MM (In Press) Parasitology Research. HERO ID: 1234059

[Less] Microsporidia are emerging opportunistic parasites. Preservation of the biological properties of microsporidian . . . [More] Microsporidia are emerging opportunistic parasites. Preservation of the biological properties of microsporidian spores is often required in research work. The present study compared two preservatives; zinc polyvinyl alcohol (zinc PVA) and potassium dichromate solutions for preservation of microsporidian spores separated from human faecal samples. After 0, 1, 2 and 4 months of storage, morphological features and staining characters of the spores were assessed by light microscopy in modified trichrome-stained smears and their viability percentages were calculated using acridine orange/ethidium bromide mixture. Also, spore infectivity was evaluated by faecal spore shedding and intestinal spore load in mice orally inoculated with the preserved spores. Results revealed that morphological features, staining characters and viability of the spores were maintained in both solutions throughout the study period. Spore infectivity was completely preserved in zinc PVA solution but showed significant reduction in potassium dichromate solution at the fourth month of the preservation duration.

Journal Article
Journal Article

Semi-automatic version of the potentiometric titration method for characterization of uranium compounds

Authors: Cristiano, BF; Delgado, JU; da Silva, JW; de Barros, PD; de Araújo, RM; Dias, FC; Lopes, RT (In Press) . HERO ID: 1234063

[Less] The potentiometric titration method was used for characterization of uranium compounds to be applied . . . [More] The potentiometric titration method was used for characterization of uranium compounds to be applied in intercomparison programs. The method is applied with traceability assured using a potassium dichromate primary standard. A semi-automatic version was developed to reduce the analysis time and the operator variation. The standard uncertainty in determining the total concentration of uranium was around 0.01%, which is suitable for uranium characterization and compatible with those obtained by manual techniques.

Journal Article
Journal Article

Protective Effects of Pine Bark Extract on Hexavalent Chromium-Induced Dermatotoxicity in Rats

Authors: Lee, IC; Kim, SH; Shin, IS; Moon, C; Park, SH; Kim, SH; Park, SC; Kim, HC; Kim, JC (In Press) . HERO ID: 1258233

[Less] The present study investigated the protective effects of pine bark extract (PBE) against hexavalent . . . [More] The present study investigated the protective effects of pine bark extract (PBE) against hexavalent chromium [Cr(VI)]-induced dermatotoxicity in rats. Skin reactions were evaluated by visual inspection, histopathological changes and oxidative stress parameters. Topical application of Cr(VI) produced a significant increase in the incidence and severity of erythema and edema upon visual inspection. Histopathological examination showed moderate to severe necrosis and desquamation in the epidermis and inflammation and hemorrhage in the dermis. In addition, an increased malondialdehyde (MDA) concentration, and decreased glutathione (GSH), catalase, superoxide dismutase, glutathione-S-transferase (GST) and glutathione reductase of the skin were observed in the Cr(VI) group. On the contrary, concomitant administration with PBE significantly improved Cr(VI)-induced dermatotoxicity, evidenced by a decrease in the incidence and severity of skin irritation and histopathological lesions in a dose-dependent manner. Moreover, PBE treatment reduced MDA concentrations and increased catalase and GST activities in skin tissues, indicating that concomitant administration with PBE effectively prevents Cr(VI)-induced oxidative damage in rats. The results indicate that PBE has a protective effect against Cr(VI)-induced dermatotoxicity and is useful as a protective agent against various dermal lesions induced by oxidative stress. Copyright © 2012 John Wiley & Sons, Ltd.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Arsenic, chromium and mercury removal using mussel shell ash or a sludge/ashes waste mixture

Authors: Seco-Reigosa, N; Peña-Rodríguez, S; Nóvoa-Muñoz, JC; Arias-Estévez, M; Fernández-Sanjurjo, MJ; Álvarez-Rodríguez, E; Núñez-Delgado, A (In Press) Environmental Science and Pollution Research. HERO ID: 1338680

[Less] Different batches of valued mussel shell and waste mussel shell ash are characterised. Shell ash has . . . [More] Different batches of valued mussel shell and waste mussel shell ash are characterised. Shell ash has pH > 12 and high electrical conductivities (between 16.01 and 27.27 dS m(-1)), while calcined shell shows pH values up to 10.7 and electrical conductivities between 1.19 and 3.55 dS m(-1). X-ray fluorescence, nitric acid digestion and water extractions show higher concentrations in shell ash for most parameters. Calcite is the dominant crystalline compound in this ash (95.6 %), followed by aragonite. Adsorption/desorption trials were performed for mussel shell ash and for a waste mixture including shell ash, sewage sludge and wood ash, showing the following percentage adsorptions: Hg(II) >94 %, As(V) >96 % and Cr(VI) between 11 and 30 % for shell ash; Hg(II) >98 %, As(V) >88 % and Cr(VI) between 30 and 88 % for the waste mixture. Hg and As desorption was <5 % for both shell ash and the waste mixture, while Cr desorption was between 92 and 45 % for shell ash, and between 19 and 0 % for the mixture. In view of that, mussel shell ash and the mixture including shell ash, sewage sludge and wood ash could be useful for Hg(II) and As(V) removal.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

WITHDRAWN: Hexavalent chromium induces premature senescence through reactive oxygen species-mediated p53 pathway in L-02 hepatocytes

Authors: Xiao, F; Hu, Q; Zeng, M; Guan, L; Liu, X; Yang, Y; Zhong, C (In Press) HERO ID: 1509895

[Less] This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes . . . [More] This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Journal Article
Journal Article

Efficient Catalytic Reduction of Hexavalent Chromium Using Palladium Nanoparticle-Immobilized Electrospun Polymer Nanofibers

Authors: Huang, Y; Ma, H; Wang, S; Shen, M; Guo, R; Cao, X; Zhu, M; Shi, X (In Press) HERO ID: 1509905

[Less] We report a facile and economic approach to fabricating catalytic active palladium (Pd) nanoparticle . . . [More] We report a facile and economic approach to fabricating catalytic active palladium (Pd) nanoparticle (NP)-immobilized electrospun polyethyleneimine (PEI)/polyvinyl alcohol (PVA) nanofibers for catalytic reduction of hexavalent chromium (Cr(VI)) to trivalent chromium (Cr(III)). In this study, PEI/PVA nanofibrous mats were first electrospun from homogeneous mixture solution of PEI and PVA, followed by cross-linking with glutaraldehyde vapor to render the fibers with good water stability. The nanofibrous mats were then alternatively soaked in potassium tetrachloropallidate (K(2)PdCl(4)) and sodium borohydride solution, and the PdCl(4)(2-) anions complexed with the free amine groups of PEI were able to be reduced to form zero-valent Pd NPs. The formed Pd NP-containing PEI/PVA nanofibers were characterized by different techniques. We show that the immobilization of Pd NPs does not significantly change the morphology of the PEI/PVA nanofibers; instead the mechanical durability of the fibers is significantly improved. The formed Pd NPs with a mean diameter of 2.6 nm are quite uniformly distributed within the fibers with a small portion of particles having a denser distribution at the outer surface of the fibers. The catalytic activity and reusability of the fabricated Pd NP-containing fibrous mats were evaluated by transformation of Cr(VI) to Cr(III) in aqueous solution in the presence of a reducing agent. Our results reveal that the Pd NP-containing nanofibrous mats display an excellent catalytic activity and reusability for the reduction of Cr(VI) to Cr(III). The facile approach to fabricating metal NP-immobilized polymer nanofibers with a high surface area to volume ratio, enhanced mechanical durability, and uniform NP distribution may be extended to prepare different NP-immobilized fibrous systems for various applications in catalysis, sensing, environmental sciences, and biomedicine.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Plant growth promotion traits and Cr (VI) reduction potentials of Cr (VI) resistant Streptomyces strains

Authors: Javaid, M; Sultan, S (In Press) Journal of Basic Microbiology. HERO ID: 1509915

[Less] The most toxic form of chromium [Cr (VI)] can be converted to less toxic Cr (III) by reduction with . . . [More] The most toxic form of chromium [Cr (VI)] can be converted to less toxic Cr (III) by reduction with the help of microbes. A total of 6 Streptomyces strains (S. matansis BG5, Streptomyces sp. RSF17, S. vinaceus CRF2, Streptomyces sp. CRF14, S. pulcher CRF17, S. griseoincarnatus SCF18) which were previously isolated from saline farmlands of Punjab, Pakistan, were used in this work. These strains showed varying levels of resistance to Cr (VI) from 800 μg ml(-1) to 1000 mg l(-1) . Their plant growth promoting and Cr (VI) reduction potentials were assessed. Two strains showed positive phosphate solubilization activity. All the strains had ability to produce indole acetic acid (IAA) except one strain (CRF17). The maximum production of IAA was observed by strain BG5 that was 16 mg l(-1) in the presence of 50 mg l(-1) of Cr (VI). All the strains were able to produce ammonia both in the absence and presence of Cr (VI). The highest Cr (VI) reduction in majority of the strains was observed at 28 °C and pH 9. The complete reduction of 150 mg l(-1) of Cr (VI) occurred after 168 hrs. The chromium (VI) concentration of 200 mg l(-1) could be reduced above 90% by most of these strains. The presence of other metals also enhanced Cr (VI) reduction by most of the strains. The results indicate the potential capacity of Streptomyces strains as tool for plant growth promotion and Cr (VI) bioremediation and also is the first report about plant growth promoting traits of Cr (VI) resistant Streptomyces strains. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).