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Arsenic speciation in Chinese Herbal Medicines and human health implication for inorganic arsenic
2013
Liu, Xiao-Juan | Zhao, Quan-Li | Sun, Guo-Xin | Williams, Paul | Lu, Xiu-Jun | Cai, Jing-Zhu | Liu, Wen-Ju
Rice and drinking water are recognized as the dominant sources of arsenic (As) for human intake, while little is known about As accumulation and speciation in Chinese Herbal Medicines (CHMs), which have been available for many hundreds of years for the treatment of diseases in both eastern and western cultures. Inorganic arsenic was the predominant species in all of CHMs samples. The levels of inorganic arsenic in CHMs from fields and markets or pharmacies ranged from 63 to 550 ng/g with a mean of 208 ng/g and 94 to 8683 ng/g with a mean of 1092 ng/g, respectively. The highest concentration was found in the Chrysanthemum from pharmacies. It indicates that the risk of inorganic As in CHMs to human health is higher in medicines from markets or pharmacies than that collected directly from fields. Some CHMs may make a considerable contribution to the human intake of inorganic arsenic.
Mostrar más [+] Menos [-]Salinisation of rivers: An urgent ecological issue
2013
Cañedo-Argüelles, Miguel | Kefford, Ben J. | Piscart, Christophe | Prat i Fornells, Narcís | Schäfer, Ralf B. | Schulz, Claus-Jürgen
Secondary salinisation of rivers and streams is a global and growing threat that might be amplified by climate change. It can have many different causes, like irrigation, mining activity or the use of salts as de-icing agents for roads. Freshwater organisms only tolerate certain ranges of water salinity. Therefore secondary salinisation has an impact at the individual, population, community and ecosystem levels, which ultimately leads to a reduction in aquatic biodiversity and compromises the goods and services that rivers and streams provide. Management of secondary salinization should be directed towards integrated catchment strategies (e.g. benefiting from the dilution capacity of the rivers) and identifying threshold salt concentrations to preserve the ecosystem integrity. Future research on the interaction of salinity with other stressors and the impact of salinization on trophic interactions and ecosystem properties is needed and the implications of this issue for human society need to be seriously considered.
Mostrar más [+] Menos [-]Fate and movement of selenium from drainage sediments disposed onto soil with and without vegetation
2013
Bañuelos, G.S. | Bitterli, C. | Schulin, R.
Disposal options for salty and selenium-laden agricultural drainage sediments are needed to protect the agricultural ecosystem in Central California. Thus, a 7-year pilot-scale field study evaluated the effects of disposing Se-laden drainage sediment onto soil that was planted with either salado grass (Sporobolus airoides ‘salado’) or cordgrass (Spartina patens ‘Flageo’), or on soil left bare with and without irrigation. Significant decreases in salinity and water-extractable and total soil Se concentrations were observed in all treatments to a depth 30 cm, while water extractable Se and salinity increased most significantly between 30 and 60 cm. Total yields increased over time for both species, while plant Se concentrations were ≈10 and 12 mg kg−1 DM for salado and cordgrass, respectively. The results show that Se and soluble salts disposed of as Se-laden drainage sediment onto light textured soils will significantly migrate to lower depths with or without vegetation.
Mostrar más [+] Menos [-]Bioavailability of nanoparticulate hematite to Arabidopsis thaliana
2013
Marusenko, Yevgeniy | Shipp, Jessie | Hamilton, George A. | Morgan, Jennifer L.L. | Keebaugh, Michael | Hill, Hansina | Dutta, Arnab | Zhuo, Xiaoding | Upadhyay, Nabin | Hutchings, James | Herckes, Pierre | Anbar, Ariel D. | Shock, Everett | Hartnett, Hilairy E.
The environmental effects and bioavailability of nanoparticulate iron (Fe) to plants are currently unknown. Here, plant bioavailability of synthesized hematite Fe nanoparticles was evaluated using Arabidopsis thaliana (A. thaliana) as a model. Over 56-days of growing wild-type A. thaliana, the nanoparticle-Fe and no-Fe treatments had lower plant biomass, lower chlorophyll concentrations, and lower internal Fe concentrations than the Fe-treatment. Results for the no-Fe and nanoparticle-Fe treatments were consistently similar throughout the experiment. These results suggest that nanoparticles (mean diameter 40.9 nm, range 22.3–67.0 nm) were not taken up and therefore not bioavailable to A. thaliana. Over 14-days growing wild-type and transgenic (Type I/II proton pump overexpression) A. thaliana, the Type I plant grew more than the wild-type in the nanoparticle-Fe treatment, suggesting Type I plants cope better with Fe limitation; however, the nanoparticle-Fe and no-Fe treatments had similar growth for all plant types.
Mostrar más [+] Menos [-]Guidelines for biomonitoring persistent organic pollutants (POPs), using lichens and aquatic mosses – A review
2013
Augusto, Sofia | Máguas, Cristina | Branquinho, Cristina
During the last decades, awareness regarding persistent organic pollutants (POPs), such dioxins and furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs), has become a cutting-edge topic, due to their toxicity, bioaccumulation and persistency in the environment. Monitoring of PCDD/Fs and PAHs in air and water has proven to be insufficient to capture deposition and effects of these compounds in the biota. To overcome this limitation, environmental biomonitoring using lichens and aquatic mosses, have aroused as promising tools. The main aim of this work is to provide a review of: i) factors that influence the interception and accumulation of POPs by lichens; ii) how lichens and aquatic bryophytes can be used to track different pollution sources and; iii) how can these biomonitors contribute to environmental health studies. This review will allow designing a set of guidelines to be followed when using biomonitors to assess environmental POP pollution.
Mostrar más [+] Menos [-]Ecological risk of estrogenic endocrine disrupting chemicals in sewage plant effluent and reclaimed water
2013
Sun, Yan | Huang, Huang | Sun, Ying | Wang, Chao | Shi, Xiao-Lei | Hu, Hong-Ying | Kameya, Takashi | Fujie, Koichi
The long-term ecological risk of micropollutants, especially endocrine disrupting chemicals (EDCs) has threatened reclaimed water quality. In this study, estrogenic activity and ecological risk of eight typical estrogenic EDCs in effluents from sewage plants were evaluated. The estrogenic activity analysis showed that steroidal estrogens had the highest estrogenic activity (ranged from 10−1 to 103 ng-E2/L), phenolic compounds showed weaker estrogenic activity (mainly ranged from 10−3 to 10 ng-E2/L), and phthalate esters were negligible. The ecological risk of the estrogenic EDCs which was characterized by risk quotient ranged from 10−4 to 103, with an order in descending: steroids estrogens, phenolic compounds and phthalate esters. The eight estrogenic EDCs were scored and sorted based on the comparison of the estrogenic activity and the ecological risk, suggesting that 17α-ethynylestradiol (EE2), estrone (E1) and estradiol (E2) should be the priority EDCs to control in municipal sewage plants.
Mostrar más [+] Menos [-]High-resolution reconstruction of atmospheric deposition of trace metals and metalloids since AD 1400 recorded by ombrotrophic peat cores in Hautes-Fagnes, Belgium
2013
Allan, Mohammed | Le Roux, Gaël | De Vleeschouwer, François | Bindler, Richard | Blaauw, Maarten | Piotrowska, Natalia | Sikorski, Jaroslaw | Fagel, Nathalie
The objective of our study was to determine the trace metal accumulation rates in the Misten bog, Hautes-Fagnes, Belgium, and assess these in relation to established histories of atmospheric emissions from anthropogenic sources. To address these aims we analyzed trace metals and metalloids (Pb, Cu, Ni, As, Sb, Cr, Co, V, Cd and Zn), as well as Pb isotopes, using XRF, Q-ICP-MS and MC-ICP-MS, respectively in two 40-cm peat sections, spanning the last 600 yr. The temporal increase of metal fluxes from the inception of the Industrial Revolution to the present varies by a factor of 5–50, with peak values found between AD 1930 and 1990. A cluster analysis combined with Pb isotopic composition allows the identification of the main sources of Pb and by inference of the other metals, which indicates that coal consumption and metallurgical activities were the predominant sources of pollution during the last 600 years.
Mostrar más [+] Menos [-]Assessment of flame retardants in river water using a ceramic dosimeter passive sampler
2013
Cristale, Joyce | Katsoyiannis, Athanasios | Chen, Chang'er | Jones, K. C. (Kevin C.) | Lacorte, Silvia
Novel brominated (BFRs) and organophosphorus (OPFRs) flame retardants were monitored in river water using the ceramic dosimeter passive sampling device with HLB (hydrophilic–lipophilic balance) as sorbent. Laboratory calibrations were performed to determine sampling rates for each compound using the Archie's law exponent. The passive sampling device was used to determine the presence of 6 BFRs in the River Aire (United Kingdom), selected according to their ubiquitous presence in the River Aire. Passive sampling integrated river water concentrations ranged from 0.010 to 5.6 μg L−1 for all OPFRs, while BFRs were not detected with this specific passive sampler configuration. Decreased sampling rates were evidenced after 3 weeks of deployment, probably due to fouling. Good agreement between integrated and snapshot water concentrations was obtained, indicating the efficiency of the passive sampler for the monitoring of OPFRs in river water.
Mostrar más [+] Menos [-]Safe use of metal-contaminated agricultural land by cultivation of energy maize (Zea mays)
2013
Van Slycken, S. | Witters, N. | Meers, E. | Peene, A. | Michels, E. | Adriaensen, K. | Ruttens, A. | Vangronsveld, J. | Du Laing, G. | Wierinck, I. | Van Dael, M. | Van Passel, S. | Tack, F.M.G.
Production of food crops on trace element-contaminated agricultural lands in the Campine region (Belgium) can be problematic as legal threshold values for safe use of these crops can be exceeded. Conventional sanitation of vast areas is too expensive and alternatives need to be investigated. Zea mays on a trace element-contaminated soil in the region showed an average yield of 53 ± 10 Mg fresh or 20 ± 3 Mg dry biomass ha−1. Whole plant Cd concentrations complied with legal threshold values for animal feed. Moreover, threshold values for use in anaerobic digestion were met. Biogas production potential did not differ between maize grown on contaminated and non-contaminated soils. Results suggested favorable perspectives for farmers to generate non-food crops profitably, although effective soil cleaning would be very slow. This demonstrates that a valuable and sustainable alternative use can be generated for moderately contaminated soils on which conventional agriculture is impaired.
Mostrar más [+] Menos [-]The impact of aluminium smelter shut-down on the concentration of fluoride in vegetation and soils
2013
Brougham, Kate M. | Roberts, Stephen R. | Davison, A. (Alan) | Port, Gordon R.
Although a great deal is known about the deposition of fluoride on vegetation, and the hazards associated with uptake by grazing herbivores, little is known about what happens to the concentration of fluoride in vegetation and soil at polluted sites once deposition ceases. The closure of Anglesey Aluminium Metals Ltd smelter, in September 2009, provided a unique opportunity to study fluoride loading once deposition stopped. Fluoride was monitored in plants and soil within 1 km of the former emission source. Fluoride concentrations in a range of plant material had decreased to background levels of 10 mg F kg−1 after 36 weeks. Concentrations of fluoride in mineral-rich soils decreased steadily demonstrating their limited potential to act as contaminating sources of fluoride for forage uptake. There were significant differences in the rate of decline of fluoride concentrations between plant species.
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