Science.gov

Sample records for alternate soil clean-up

  1. Clean-up criteria for remediation of contaminated soils

    SciTech Connect

    Nguyen, H.D.; Wilson, J.R.; Sato, Chikashi

    1997-08-01

    {open_quotes}How clean is clean?{close_quotes} is a question commonly raised in the remediation of contaminated soils. To help with the answer, criteria are proposed to serve as guidelines for remedial actions and to define a clean-up level such that the remaining contaminant residuals in the soil will not violate the Drinking Water Standards (DWS). The equations for computing those criteria are developed from the principle of conservation of mass and are functions of the maximum concentration level in the water (MCL) and the sorption coefficient. A multiplier, ranging from 10 to 1000, is also factored into the soil standard equation to reflect the effectiveness of various remediation techniques. Maximum allowable concentration in the soil (MSCL) is presented for several contaminants which are being regulated at the present time. Future modifications are recommended for better estimates of the MSCLs as additional transport mechanisms are incorporated to account for other potentially dominant effects.

  2. Application of State and Federal Guidelines for Establishing Alternate Soil Clean-Up Levels for the Protection of Groundwater at the Hanford Site

    SciTech Connect

    Leary, K.; McMahon, W.; Hoover, J.

    2008-07-01

    Risk-based soil cleanup levels that are protective of groundwater have been calculated for use in environmental remediation activities at the Hanford Site using vadose zone fate and transport modeling. The determination of soil cleanup levels is important because it involves the technical basis for the levels of contamination that can be left in place, which are protective of human health and the environment. The determination of risk-based soil cleanup levels is an especially important issue at the Hanford Site where site conditions such as a semi-arid climate, and a thick vadose zone of over 100 meters necessitate the use of appropriate risk-based methods. In the absence of an alternative risk-based approach, the cleanup levels default to background, detection limits, or simplistic formulas not intended for applications involving these distinctive site conditions. However, the use of vadose zone fate and transport modeling for risk-based applications such as the determination of soil cleanup levels in the vadose zone are not as well established as modeling for groundwater applications. Thus, the use of models in this manner involves additional challenges for the demonstration of the efficacy of its use for risk-based applications, in accordance with federal and state regulatory requirements and guidelines. An approach has been developed to integrate with federal and state regulatory guidelines in conjunction with the development of the risk-based methodology. Demonstration of integration with these guidelines primarily involves documentation of the objectives of the problem to be solved, the technical basis and rationale associated with the selection of an appropriate risk-based method (e.g., model type and code selection), and documentation associated with the use of the model, e.g., conceptual site model, parameter estimation, uncertainty and assumptions analyses, and model results. (authors)

  3. An alternative clean-up column for the determination of polychlorinated biphenyls in solid matrices.

    PubMed

    Ndunda, Elizabeth N; Madadi, Vincent O; Mizaikoff, Boris

    2015-12-01

    The need for continuous monitoring of polychlorinated biphenyls (PCBs) has necessitated the development of analytical techniques that are sensitive and selective with minimal reagent requirement. In light of this, we developed a column for clean-up of soil and sediment extracts, which is less demanding in terms of the amount of solvent and sorbent. The dual-layer column consists of acidified silica gel and molecularly imprinted polymers (MIPs). MIPs were synthesized via aqueous suspension polymerization using PCB 15 as the dummy template, 4-vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the cross-linker and the obtained particles characterized via SEM, BET, and batch rebinding assays. Pre-concentration of the spiked real-world water sample using MISPE gave recoveries between 85.2 and 104.4% (RSD < 8.69). On the other hand, the specific dual-layer column designed for clean-up of extracts from complex matrices provided recoveries of 91.6-102.5% (RSD < 4%) for spiked soil, which was comparable to clean-up using acidified silica (70.4-90.5%; RSD < 3.72%) and sulfoxide modified silica (89.7-103.0%; RSD < 13.0%). However, the polymers were reusable maintaining recoveries of 79.8-111.8% after 30 cycles of regeneration and re-use, thereby availing a cost-effective clean-up procedure for continuous monitoring of PCBs. Method detection limits were 0.01-0.08 ng g(-1) and 0.002-0.01 ng mL(-1) for solid matrices and water, respectively. PMID:26560633

  4. Application of electrokinetics for stimulating microbial clean-up of contaminated soils

    NASA Astrophysics Data System (ADS)

    Thompson, I.; Lear, G.

    2006-05-01

    Given sufficient time there are few synthetic compounds that can resist microbial degradation, a fact exploited in environmental clean-up. Despite this the performance of micro-organisms in remedial technologies is often sub-optimal. There are many reasons for the failure of indigenous microbial communities to reduce contaminant concentrations, including issues of bioavailability and the inability of the contaminants to switch on genes (catabolic) responsible for contaminant degradation. Even if the presence of the required catabolic genes is confirmed, there continues to be a significant need to develop procedures to stimulate their activity. We have investigated the potential of soil electrokinetics (3-4 A m-2) to stimulate microbial degradation of organic pollutants and move the soil contaminants relative to the degradative microorganisms, so increasing contact between the two components. Using soils contaminated with pentachlorophenol as our model laboratory system, we have demonstrated that the technique is effective at causing gross and controlled movement of PCP through soils at the laboratory-scale. It can also stimulate rates (up to 25% over that of the control) by which introduced bacteria degrade the contaminant. The additional potential benefits of electrokinetics in regard to stimulating microbial activity and soil clean-up will be discussed.

  5. Soil clean up by in-situ aeration. 6. Effects of variable permeabilities

    SciTech Connect

    Gomez-Lahoz, C.; Rodriguez-Maroto, J.M. ); Wilson, D.J. )

    1991-02-01

    Soil vapor stripping (vacuum extraction) has become an important tool in the remediation of hazardous waste sites contaminated with volatile organic compounds (VOCs) in the vadose zone. A mathematical model for in-situ soil vapor stripping is developed and used to examine the effects of a spatially variable pneumatic permeability tensor on the rate of clean-up of a site contaminated with volatile organic compounds. Runs are made with low-permeability clay lenses placed at various locations in the domain of interest; also the effect of soil moisture distribution on the soil gas flow field is examined. The model permits one to carry out a sensitivity analysis of the effects of heterogeneity in the permeability, and to develop strategies for minimizing the damaging effects of domains of low permeability.

  6. Cleaning-up atrazine-polluted soil by using Microbial Electroremediating Cells.

    PubMed

    Domínguez-Garay, Ainara; Boltes, Karina; Esteve-Núñez, Abraham

    2016-10-01

    Biodegradation of pollutants in soil is greatly limited by the availability of terminal electron acceptors required for supporting microbial respiration. Such limitation can be overcome if soil-buried electrodes accept the electrons released in the microbial metabolism. We propose the term bioelectroventing for such a environmental treatment. The process would be performed in a device so-called Microbial Electroremediating Cell. Indeed, our studies demonstrate that the presence of electrodes as electron acceptors effectively stimulated by 5-fold the biodegradation rate of the herbicide atrazine (2-chloro-4-ethylamino-6-isopropyl amino-1,3,5-triazine) in comparison with soil natural attenuation. Furthermore, a different set of toxicological test using Pseudokirchneriella subcapitata green alga e, Salmonella typhimorium bacteria and Sorghum saccharatum plant seeds respectively, confirm that atrazine-polluted soil can be effectively cleaned-up in short time by the use of MERCs. PMID:27448317

  7. Enhanced phyto-extraction not a feasible option to clean up uranium contaminated soil

    SciTech Connect

    Vandenhove, Hildegarde; Duquene, Lise; Wannijn, Jean; Filip, Tack; Baeten, Joke

    2007-07-01

    Available in abstract form only. Full text of publication follows: A greenhouse experiment was set up to evaluate the potential of enhanced phyto-extraction to clean up U contaminated soils. One soil had a naturally high U concentration and the other soil was impacted by effluents from the former radium extraction industry. Enhancement of U solubility and uptake by plants (ryegrass and Indian mustard) was monitored after addition of 5 chemical amendments (5 mmol kg{sup -1} soil dry weight): citric acid, ammonium citrate-citric acid mixture, oxalic acid, EDDS and NTA. Uranium solubilization and uptake were highly influenced by the amendment applied and soil-plant combinations. Citric acid was most effective in increasing U solubility (up to 18-fold increase). Citric acid and the ammonium citrate-citric acid mixture were most effective in increasing U uptake by ryegrass (up to 6-fold). For Indian mustard, EDDS and citric acid were most effective (up to 9- fold). In the optimal scenario only 0.16 % of the total uranium present in the soil could be extracted with one harvest and it would take more than 200 years to reduce the initial uranium content with 10 %. Based on these results, we must conclude that phyto-extraction is not a feasible technique to decrease the uranium concentration of historically contaminated soils. (authors)

  8. From conceptual model to remediation: bioavailability, a key to clean up heavy metal contaminated soils.

    NASA Astrophysics Data System (ADS)

    Petruzzelli, Gianniantonio; Pedron, Francesca; Pezzarossa, Beatrice

    2013-04-01

    Processes of metal bioavailability in the soil To know the bioavailability processes at site specific levels is essential to understand in detail the risks associated with pollution, and to support the decision-making process, i.e. description of the conceptual model and choice of clean up technologies. It is particularly important to assess how chemical, physical and biological processes in the soil affect the reactions leading to adsorption, precipitation or release of contaminants. The measurement of bioavailability One of the main difficulties in the practical application of the bioavailability concept in soil remediation is the lack of consensus on the method to be used to measure bioavailability. The best strategy is to apply a series of tests to assess bioavailability, since no applicable method is universally valid under all conditions. As an example, bioavailability tests for phytotechnology application should consider two distinct aspects: a physico-chemical driven solubilization process and a physiologically driven uptake process. Soil and plant characteristics strongly influence bioavailability. Bioavailability as a tool in remediation strategies Bioavailability can be used at all stages in remediation strategies: development of the conceptual model, evaluation of risk assessment, and selection of the best technology, considering different scenarios and including different environmental objectives. Two different strategies can be followed: the reduction and the increase of bioavailability. Procedures that reduce bioavailability aim to prevent the movement of pollutants from the soil to the living organisms, essentially by: i) removal of the labile phase of the contaminant, i.e. the fraction which is intrinsic to the processes of bioavailability (phytostabilization); ii) conversion of the labile fraction into a stable fraction (precipitation or adsorption); iii) increase of the resistance to mass transfer of the contaminants (inertization). Procedures

  9. Capacity of the bioremediation technology for clean-up of soil and groundwater contaminated with petroleum hydrocarbons.

    PubMed

    Masak, Jan; Machackova, Jirina; Siglova, Martina; Cejkova, Alena; Jirku, Vladimir

    2003-01-01

    A column reactor was designed and used to simulate conditions affecting the bioremediations of petroleum hydrocarbons. The work illustratively describes the aerobic (model) clean-up of soil samples enabling to predict the efficiency of a technology installed in parallel on contaminated former airport. The data showing the performance of thus precharacterized technology are presented. PMID:14524696

  10. Addressing the challenges of tetracycline analysis in soil: extraction, clean-up, and matrix effects in LC-MS.

    PubMed

    O'Connor, Seamus; Locke, Jonas; Aga, Diana S

    2007-11-01

    An optimized extraction and clean-up method for the analysis of chlortetracycline, doxycycline, oxytetracycline, and tetracycline antibiotics in soil is presented in this work. Soil extraction using different solvents was performed, but the use of a 50 : 50 (v/v) methanol : acetate buffer (pH 8) solvent mixture in a pressurized liquid extraction (PLE) system proved to give the best extraction efficiency and reproducibility. The effect of soil composition on the PLE extraction efficiency was also examined, and results indicated that recovery data for one soil is not necessarily consistent with other soil types containing different compositions of clay and organic matter content. The percent recoveries of the optimized PLE method varied between the soils and ranged from 22-99%, depending on soil type, and more specifically clay content. In addition, the extent of ionization suppression caused by co-extracted humic acids was examined in an ion trap mass spectrometer (MS), and a single quadrupole MS. It was found that under positive electrospray ionization, the single quadrupole MS was less susceptible to ionization suppression than the ion trap MS. Therefore, various sample clean-up procedures were evaluated to selectively reduce the amount of co-extracted humic acids in the soil extracts. The most effective clean-up was obtained from the use of StrataX sorbent in combination with a strong anion exchange cartridge. PMID:17968453

  11. Methodology and data used for estimating the complex-wide impacts of alternative environmental restoration clean-up goals

    SciTech Connect

    Shay, M.R.; Short, S.M.; Stiles, D.L.

    1994-03-01

    This paper describes the methodologies and data used for estimating the complex-wide impacts of alternative strategies for conducting remediation of all DOE sites and facilities, but does not address issues relating to Waste Management capabilities. Clean-up strategies and their corresponding goals for contaminated media may be driven by concentration-based regulatory standards, land-use standards (e.g., residential, industrial, wild life reserve, or totally restricted), risk-based standards, or other standards determined through stakeholder input. Strategies implemented to achieve these goals usually require the deployment of (a) clean-up technologies to destroy, remove, or contain the contaminants of concern; (b) institutional controls to prevent potential receptors from coming into contact with the contaminants; or (c) a combination of the above.

  12. Cleaning up

    SciTech Connect

    Perry, T.S.

    1993-02-01

    This article reports on the electronics manufacturer's response to findings that chemicals used in manufacturing integrated circuits induced miscarriages in plant workers and other environmental problems such as ozone depletion and the use of heavy metals and toxic gases in manufacturing. The topics of the article include the finding that a photoresist is at fault, the phase-out of ethylene glycol ethers, alternatives to ethylene glycol ethers, ozone-eating CFCs, use of citrus derived substitutes for CFCs, alternative manufacturing processes, substitutes for other ozone depleting chemicals, and the use of heavy metals in electronics manufacturing.

  13. Cleaning up our act: Alternatives for hazardous solvents used in cleaning

    SciTech Connect

    Shoemaker, J.D.; Meltzer, M.; Miscovich, D.; Montoya, D.; Goodrich, P.; Blycker, G.

    1994-01-01

    Lawrence Livermore National Laboratory (LLNL) has studied more than 70 alternative cleaners as potential replacements for chlorofluorocarbons (CFCs), halogenated hydrocarbons (e.g., trichloroethylene and trichloroethane), hydrocarbons (e.g., toluene and Stoddard Solvent), and volatile organic compounds (e.g., acetone, alcohols). This report summarizes LLNL`s findings after testing more than 45 proprietary formulations on bench-scale testing equipment and in more than 60 actual shops and laboratories. Cleaning applications included electronics fabrication, machine shops, optical lenses and hardware, and general cleaning. Most of the alternative cleaners are safer than the solvents previously used and many are nonhazardous, according to regulatory criteria.

  14. Phytoextraction for clean-up of low-level uranium contaminated soil evaluated.

    PubMed

    Vandenhove, H; Van Hees, M

    2004-01-01

    Spills in the nuclear fuel cycle have led to soil contamination with uranium. In case of small contamination just above release levels, low-cost yet sufficiently efficient remedial measures are recommended. This study was executed to test if low-level U contaminated sandy soil from a nuclear fuel processing site could be phytoextracted in order to attain the required release limits. Two soils were tested: a control soil (317 Bq 238U kg(-1)) and the same soil washed with bicarbonate (69 Bq 238U kg(-1)). Ryegrass (Lolium perenne cv. Melvina) and Indian mustard (Brassica juncea cv. Vitasso) were used as test plants. The annual removal of soil activity by the biomass was less than 0.1%. The addition of citric acid (25 mmol kg(-1)) 1 week before the harvest increased U uptake up to 500-fold. With a ryegrass and mustard yield of 15,000 and 10,000 kg ha(-1), respectively, up to 3.5% and 4.6% of the soil activity could be removed annually by the biomass. With a desired activity reduction level of 1.5 and 5 for the bicarbonate-washed and control soil, respectively, it would take 10-50 years to attain the release limit. However, citric acid addition resulted in a decreased dry weight production. PMID:15162854

  15. PHYTOREMEDIATION: USING PLANTS TO CLEAN UP CONTAMINATED SOIL, GROUNDWATER, AND WASTEWATER

    EPA Science Inventory

    Phytoremediation is an emerging cleanup technology for contaminated soils, groundwater, and wastewater that is both low-tech and low-cost. The cleanup technology is defined as the use of green plants to remove, contain, or render harmless such environmental contaminants as heavy ...

  16. Phytoremediation: using green plants to clean up contaminate soil, groundwater, and wastewater

    SciTech Connect

    Negri, M.C.; Hinchman, R.R.; Gatliff, E.G.

    1996-07-01

    Phytoremediation, an emerging cleanup technology for contaminated soils, groundwater, and wastewater that is both low-tech and low-cost, is defined as the engineered use of green plants (including grasses, forbs, and woody species) to remove, contain, or render harmless such environmental contaminants as heavy metals, trace elements, organic compounds and radioactive compounds in soil or water. Our research includes a successful field demonstration of a plant bioreactor for processing the salty wastewater from petroleum wells; the demonstration is currently under way at a natural gas well site in Oklahoma, in cooperation with Devon Energy Corporation. A greenhouse experiment on zinc uptake in hybrid poplar (Populus sp.) was initiated in 1995. These experiments are being conducted to confirm and extend field data indicating high levels of zinc (4,200 ppm) in leaves of hybrid poplar growing as a cleanup system at a site with zinc contamination in the root zone of some of the trees. Analyses of soil water from experimental pots that had received several doses of zinc indicated that the zinc was totally sequestered by the plants in about 4 hours during a single pass through the root system. The data also showed concentrations of sequestered metal of >38,000 ppm Zn in the dry root tissue. These levels of sequestered zinc exceed the levels found in either roots or tops of many of the known ``hyperaccumulator`` species. Because the roots sequester most of the contaminant taken up in most plants, a major objective of this program is to determine the feasibility of root harvesting as a method to maximize the removal of contaminants from soils. Available techniques and equipment for harvesting plant roots, including young tree roots, are being evaluated and modified as necessary for use with phytoremediation plants.

  17. Soil clean up by in-situ aeration. VII. High-speed modeling of diffusion kinetics

    SciTech Connect

    Rodriguez-Maroto, J.M. ); Wilson, D.J. )

    1991-01-01

    A mathematical model for soil vacuum extraction is developed which allows the modeling of vapor stripping from media of highly heterogeneous permeability, in which one may not be able to make the assumption of local equilibrium between the stationary phase(s) and the moving vapor phase with respect to volatile organic compound (VOC) transport. A lumped parameter approximation is used to deal with the kinetics of diffusion (and/or desorption) of the VOC from the interiors of lumps of clay or porous bedrock out into the advecting soil gas. This model, which makes the steady-state approximation for the VOC vapor concentrations, typically uses less than one-twentieth the computer time of an earlier nonsteady-state model and gives results which are in excellent agreement with that model. This model also yields results which are in agreement with a local equilibrium model if the rate constant for diffusion/desorption is large. The effects of impermeable caps and passive vent wells decrease as the rate of diffusion/desorption is decreased.

  18. Deriving site-specific soil clean-up values for metals and metalloids: Rationale for including protection of soil microbial processes

    PubMed Central

    Kuperman, Roman G; Siciliano, Steven D; Römbke, Jörg; Oorts, Koen

    2014-01-01

    Although it is widely recognized that microorganisms are essential for sustaining soil fertility, structure, nutrient cycling, groundwater purification, and other soil functions, soil microbial toxicity data were excluded from the derivation of Ecological Soil Screening Levels (Eco-SSL) in the United States. Among the reasons for such exclusion were claims that microbial toxicity tests were too difficult to interpret because of the high variability of microbial responses, uncertainty regarding the relevance of the various endpoints, and functional redundancy. Since the release of the first draft of the Eco-SSL Guidance document by the US Environmental Protection Agency in 2003, soil microbial toxicity testing and its use in ecological risk assessments have substantially improved. A wide range of standardized and nonstandardized methods became available for testing chemical toxicity to microbial functions in soil. Regulatory frameworks in the European Union and Australia have successfully incorporated microbial toxicity data into the derivation of soil threshold concentrations for ecological risk assessments. This article provides the 3-part rationale for including soil microbial processes in the development of soil clean-up values (SCVs): 1) presenting a brief overview of relevant test methods for assessing microbial functions in soil, 2) examining data sets for Cu, Ni, Zn, and Mo that incorporated soil microbial toxicity data into regulatory frameworks, and 3) offering recommendations on how to integrate the best available science into the method development for deriving site-specific SCVs that account for bioavailability of metals and metalloids in soil. Although the primary focus of this article is on the development of the approach for deriving SCVs for metals and metalloids in the United States, the recommendations provided in this article may also be applicable in other jurisdictions that aim at developing ecological soil threshold values for protection of

  19. Soil clean up by in-situ aeration. 8. Effects of system geometry on vapor extraction efficiency

    SciTech Connect

    Rodriguez-Maroto, J.M.; Gomez-Lahoz, C. ); Wilson, D.J. )

    1991-08-01

    Soil vapor extraction (SVE, soil vacuum extraction, soil vapor stripping, soil venting) is now a well-established technique for removing volatile organic compounds (VOCs) from the vadose zone at hazardous waste sites, leaks, spills, etc. A mathematical model for soil vapor extraction by means of a buried horizontal slotted pipe was used to examine the effects of a number of geometrical system parameters on the efficiency of soil vapor extraction. Parameters investigated include depth of pipe relative to the water table, size of impermeable overlying cap, and presence or absence of passive horizontal vent pipes The results demonstrate the utility of mathematical modeling for exploring cheaply and rapidly the effects of variations in soil vapor extraction system design.

  20. Innovative integration of decommissioning and deactivation program with soil-groundwater clean up program has positive results on budget and schedule: a case study

    SciTech Connect

    Schappell, Bruce G.; Rucker, Gregory G.

    2007-07-01

    An innovative approach to integrate the activities of a decommissioning and deactivation program (D and D) with a soil-groundwater clean up program has had significant positive results saving both money and time at the Department of Energy's Savannah River Site. The accomplishments that have been achieved by the combining the two programs have been remarkable including significant cost savings, economies of scale for sampling and document generation, and alignment of common objectives. Because of the coordination of both activities area-wide 'end states' can be formulated and be consistent with the customers' cleanup goals and federal regulations. This coordinates and aligns both the environmental clean up and D and D objectives because each must be addressed simultaneously and comprehensively. In this respect, resources from both organizations can be pooled to take advantage of the strengths of each. The new approach allows more efficient use of lean financial resources and optimizes workforce activities to attain the common objectives while being more cost effective, more protective of the environment, and optimizing the use existing resources. (authors)

  1. Innovative Integration of Decommissioning and Deactivation Program with Soil-Groundwater Clean Up Program Has Positive Results on Budget and Schedule: A Case Study

    SciTech Connect

    Schappell, B; Rucker, G

    2007-07-25

    An innovative approach to integrate the activities of a decommissioning and deactivation program (D&D) with a soil-groundwater clean up program has had significant positive results saving both money and time at the Department of Energy's Savannah River Site. The accomplishments that have been achieved by the combining the two programs have been remarkable including significant cost savings, economies of scale for sampling and document generation, and alignment of common objectives. Because of the coordination of both activities area-wide ''end states'' can be formulated and be consistent with the customers' cleanup goals and federal regulations. This coordinates and aligns both the environmental clean up and D&D objectives because each must be addressed simultaneously and comprehensively. In this respect, resources from both organizations can be pooled to take advantage of the strengths of each. The new approach allows more efficient use of lean financial resources and optimizes workforce activities to attain the common objectives while being more cost effective, more protective of the environment, and optimizing the use existing resources.

  2. Enrichment of perfluorinated alkyl substances on polyethersulfone using 1-methylpyperidine as ion-pair reagent for the clean-up of carrot and amended soil extracts.

    PubMed

    Bizkarguenaga, Ekhiñe; Zabaleta, Itsaso; Iparraguirre, Arantza; Aguirre, Josu; Fernández, Luis Ángel; Berger, Urs; Prieto, Ailette; Zuloaga, Olatz

    2015-10-01

    The development of a simple, cheap and environment friendly analytical method for the simultaneous determination of different perfluoroalkyl substances (PFASs) including seven perfluoroalkyl carboxylic acids, three perfluoroalkane sulfonic acids and perfluorooctanesulfonamide in carrot and amended soil was carried out in the present work. The method was based on focused ultrasound solid-liquid extraction followed by extract clean-up through enrichment of the target compounds on a polymeric material using an ion-pair reagent and detection by liquid chromatography-tandem mass spectrometry. The following variables affecting the clean-up step were evaluated: the nature of the polymeric material (polyethersulfone, PES, versus silicone rod), the amount of the polymeric material (from 1 to 9 mg), the ion-pair reagent (1-methylpyperidine, 1-MP, versus tetrabutylammonium salts), the concentration of the ion-pair reagent (from 5 to 50 mM) and the extraction time (from 15 min to 24 h). Optimum clean-up conditions were obtained using preconcentration on 9 mg of PES polymeric material combined with 5 mM 1-MP as ion-pair reagent for 3h. The method was validated in terms of apparent recoveries in the range of 77-140% and 95-137% at the low concentration (50 ng g(-1)) and in the range of 70-136% and 79-132% at the high concentration (290 ng g(-1)) for amended soil and carrot, respectively, after correction with the corresponding labeled standards. Precision, as relative standard deviation, was within 2-23%, while method detection limits were 0.31-2.85 ng g(-1) for amended soil and 0.11-1.83 ng g(-1) for carrot. In the absence of a certified reference material for the target analytes in the matrices studied, inter-method comparison was carried out and the same samples were processed using two independent clean-up procedures, the one developed in the present work and a classical based on solid-phase extraction. Statistically comparable results were obtained according to the one

  3. CLEANING UP PESTICIDE CONTAMINATED SOILS: COMPARING EFFECTIVENESS OF SUPERCRITICAL FLUID EXTRACTION WITH SOLVENT EXTRACTION AND LOW TEMPERATURE THERMAL DESORPTION

    EPA Science Inventory

    Bench-scale supercritical fluid extraction (SFE) studies were performed on soil samples obtained from a Superfund site that is contaminated with high levels of p,p,-DDT, p,p,-DDD, p,p,-DDE, toxaphene and hexachlorocyclohexane. The effectiveness of supercritical fluid extraction ...

  4. Metal associations in soils before and after EDTA extractive decontamination: implications for the effectiveness of further clean-up procedures.

    PubMed

    Barona, A; Aranguiz, I; Elías, A

    2001-01-01

    The distribution of Pb, Ni and Zn in two contaminated soils was determined before and after treating the soils with an EDTA solution. After the EDTA extraction, the proportion of Pb accumulated in the acid-extractable fraction considerably increased, which was related to the greater degree of metal extraction from the other fractions. EDTA was also able to extract certain amounts of Pb, Zn and Ni from the silicate matrix, which implied that these extractable amounts were not so strongly fixed to the residual fraction as previously supposed. As a consequence, after EDTA application, metal content (especially Pb) remained more weakly adsorbed to soil components (more easily leachable), potentially favouring the application of phytoremediation technologies. The extraction recoveries (for only one application) were generally low for the three metals (33-37% for Pb, 5-11% for Ni and 14-19% for Zn), although this fact is an advantage as plants would not be able to assimilate very high mobilised contents of metals. PMID:11351764

  5. Enantioseparation and determination of triticonazole enantiomers in fruits, vegetables, and soil using efficient extraction and clean-up methods.

    PubMed

    Zhang, Qing; Gao, Beibei; Tian, Mingming; Shi, Haiyan; Hua, Xiude; Wang, Minghua

    2016-01-15

    An efficient and novel enantioseparation and determination method was developed to quantify the enantiomers of chiral triazole fungicide triticonazole in fruit, vegetable, and soil samples. Under the optimal chromatographic conditions, the enantiomers of triticonazole were completely enantioseparated on a cellulose tris(3-chloro-4-methyl phenyl carbamate) column with relatively good resolution (Rs=14.04). Two cleanup methods were compared to quantify the enantiomers of triticonazole. The modified QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction procedure was achieved with sufficient recoveries and low detection limits. Good recoveries were obtained for the two enantiomers ranging from 84.1% to 103.2% in the six matrices, and the relative standard deviation values ranged from 1.7% to 8.4%. Under the optimal conditions, the obtained limits of detection (LODs) were in the range of 0.0012-0.0031mg/kg for the two enantiomers, and the limits of quantification (LOQs) were in the range of 0.0036-0.0091mg/kg, which were lower than the maximum residue levels established in Japan. In addition, the stereochemical structure of triticonazole enantiomers were determined for the first time using a combination of experimental and predicted electronic circular dichroism (ECD) spectra. The first eluted enantiomer was confirmed to be (+)-(S)-triticonazole. These results indicate that the proposed method is convenient and reliable for the enantioselective detection of triticonazole in authentic samples. The proposed method could be widely applicable for investigating the stereoselective degradation of triticonazole in food and environmental matrices, providing additional information for reliable risk assessment of triazole fungicides. PMID:26724558

  6. Cleaning Up Our Drinking Water

    SciTech Connect

    Manke, Kristin L.

    2007-08-01

    Imagine drinking water that you wring out of the sponge you’ve just used to wash your car. This is what is happening around the world. Rain and snow pass through soil polluted with pesticides, poisonous metals and radionuclides into the underground lakes and streams that supply our drinking water. “We need to understand this natural system better to protect our groundwater and, by extension, our drinking water,” said Pacific Northwest National Laboratory’s Applied Geology and Geochemistry Group Manager, Wayne Martin. Biologists, statisticians, hydrologists, geochemists, geologists and computer scientists at PNNL work together to clean up contaminated soils and groundwater. The teams begin by looking at the complexities of the whole environment, not just the soil or just the groundwater. PNNL researchers also perform work for private industries under a unique use agreement between the Department of Energy and Battelle, which operates the laboratory for DOE. This research leads to new remediation methods and technologies to tackle problems ranging from arsenic at old fertilizer plants to uranium at former nuclear sites. Our results help regulators, policy makers and the public make critical decisions on complex environmental issues.

  7. Encapsulation as a passive soil remediation alternative

    SciTech Connect

    Mario, B.R. De

    1996-12-31

    By implementing institutional and engineering controls, a passive, cost-effective, remedial alternative has allowed redevelopment of an abandoned, industrial, site located in Newark, New Jersey. Soil and groundwater contaminants at the site include volatile and semi-volatile organic compounds and metals. The New Jersey Department of Environmental Protection (NJDEP) recognized the impracticality of requiring an aggressive, localized, remedial action to clean up contaminated soil and groundwater in a region that has historically used fill to create land along the state`s waterways. By placing an institutional control, known as a Declaration of Environmental Restriction (DER), on the property, the NJDEP allowed contaminated fill to remain on site and approved encapsulation as the remedial action for the soil. The approved engineering control, encapsulation, consisted of the design and placement of an asphalt pavement cap that covered the affected areas of concern. The asphalt pavement cap prevents direct human contact to contaminated soil and leaching of contaminants in the soil into the groundwater by surface water infiltration. This paper focuses on the subsurface soil investigation and establishment of the DER. The benefits of this remedial alternative are: (1) the urban redevelopment of contaminated land while simultaneously ensuring protection to human health and the environment; (2) costs savings of not having to clean up a regional problem as if it were local; and (3) the facilitation of a property transfer transaction without the risk of future liability for an historical problem.

  8. TRACKING CLEAN UP AT HANFORD

    SciTech Connect

    CONNELL, C.W.

    2005-05-27

    The Hanford Federal Facility Agreement and Consent Order, known as the ''Tri-Party Agreement'' (TPA), is a legally binding agreement among the US Department of Energy (DOE), The Washington State Department of Ecology, and the US Environmental Protection Agency (EPA) for cleaning up the Hanford Site. Established in the 1940s to produce material for nuclear weapons as part of the Manhattan Project, Hanford is often referred to as the world's large environmental cleanup project. The Site covers more than 580 square miles in a relatively remote region of southeastern Washington state in the US. The production of nuclear materials at Hanford has left a legacy of tremendous proportions in terms of hazardous and radioactive waste. From a waste-management point of view, the task is enormous: 1700 waste sites; 450 billion gallons of liquid waste; 70 billion gallons of contaminated groundwater; 53 million gallons of tank waste; 9 reactors; 5 million cubic yards of contaminated soil; 22 thousand drums of mixed waste; 2.3 tons of spent nuclear fuel; and 17.8 metric tons of plutonium-bearing material and this is just a partial listing. The agreement requires that DOE provide the results of analytical laboratory and non-laboratory tests/readings to the lead regulatory agency to help guide then in making decisions. The agreement also calls for each signatory to preserve--for at least ten years after the Agreement has ended--all of the records in it, or its contractors, possession related to sampling, analysis, investigations, and monitoring conducted. The Action Plan that supports the TPA requires that Ecology and EPA have access to all data that is relevant to work performed, or to be performed, under the Agreement. Further, the Action Plan specifies two additional requirements: (1) that EPA, Ecology and their respective contractor staffs have access to all the information electronically, and (2) that the databases are accessible to, and used by, all personnel doing TPA

  9. Deriving site-specific clean-up criteria to protect ecological receptors (plants and soil invertebrates) exposed to metal or metalloid soil contaminants via the direct contact exposure pathway

    PubMed Central

    Checkai, Ron; Van Genderen, Eric; Sousa, José Paulo; Stephenson, Gladys; Smolders, Erik

    2014-01-01

    Soil contaminant concentration limits for the protection of terrestrial plants and soil invertebrates are commonly based on thresholds derived using data from laboratory ecotoxicity tests. A comprehensive assessment has been made for the derivation of ecological soil screening levels (Eco-SSL) in the United States; however, these limits are conservative because of their focus on high bioavailability scenarios. Here, we explain and evaluate approaches to soil limit derivation taken by 4 jurisdictions, 2 of which allow for correction of data for factors affecting bioavailability among soils, and between spiked and field-contaminated soils (Registration Evaluation Authorisation and Restriction of Chemicals [REACH] Regulation, European Union [EU], and the National Environment Protection Council [NEPC], Australia). Scientifically advanced features from these methods have been integrated into a newly developed method for deriving soil clean-up values (SCVs) within the context of site-specific baseline ecological risk assessment. Resulting site-specific SCVs that account for bioavailability may permit a greater residual concentration in soil when compared to generic screening limit concentrations (e.g., Eco-SSL), while still affording acceptable protection. Two choices for selecting the level of protection are compared (i.e., allowing higher effect levels per species, or allowing a higher percentile of species that are potentially unprotected). Implementation of this new method is presented for the jurisdiction of the United States, with a focus on metal and metalloid contaminants; however, the new method can be used in any jurisdiction. A case study for molybdate shows the large effect of bioavailability corrections and smaller effects of protection level choices when deriving SCVs. Integr Environ Assess Manag 2014;10:346–357. PMID:24470189

  10. Evaluation of alternative sorbents for dispersive solid-phase extraction clean-up in the QuEChERS method for the determination of pesticide residues in rice by liquid chromatography with tandem mass spectrometry.

    PubMed

    Cabrera, Liziara da C; Caldas, Sergiane S; Prestes, Osmar D; Primel, Ednei G; Zanella, Renato

    2016-05-01

    Many compounds are used for pest control during the production and storage of rice, making it necessary to employ multiclass methods for pesticide residues determination. For this purpose, QuEChERS-based methods are very efficient, fast and accurate, and improvements in the clean-up step are important, especially for complex matrices, like cereals. In this work, different sorbents such as chitosan, florisil(®) , alumina, diatomaceous earth, graphitized carbon black, besides the commonly used primary secondary amine and octadecylsilane, were evaluated for dispersive solid-phase extraction clean-up in acetate-buffered QuEChERS method for the determination of residues of 20 representative pesticides and one metabolite in rice by liquid chromatography coupled to tandem mass spectrometry. The sorbent C18 presented the best results, however, chitosan showed similar results, and the best performance among the unconventional sorbents evaluated. The method limit of quantification, attending accuracy (70-120% recovery) and precision (RSD ≤20%) criteria, ranged from 5 to 20 μg/kg. Results showed that chitosan is an effective alternative to reduce analysis costs, maintaining the method reliability and accuracy. PMID:27004927

  11. 48 CFR 36.512 - Cleaning up.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Cleaning up. 36.512... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.512 Cleaning up. The contracting officer shall insert the clause at 52.236-12, Cleaning Up, in solicitations and contracts when a...

  12. 48 CFR 36.512 - Cleaning up.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Cleaning up. 36.512... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.512 Cleaning up. The contracting officer shall insert the clause at 52.236-12, Cleaning Up, in solicitations and contracts when a...

  13. 48 CFR 36.512 - Cleaning up.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Cleaning up. 36.512... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.512 Cleaning up. The contracting officer shall insert the clause at 52.236-12, Cleaning Up, in solicitations and contracts when a...

  14. 48 CFR 36.512 - Cleaning up.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Cleaning up. 36.512... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.512 Cleaning up. The contracting officer shall insert the clause at 52.236-12, Cleaning Up, in solicitations and contracts when a...

  15. 48 CFR 36.512 - Cleaning up.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Cleaning up. 36.512... CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.512 Cleaning up. The contracting officer shall insert the clause at 52.236-12, Cleaning Up, in solicitations and contracts when a...

  16. Determination of benazolin-ethyl residues in soil and rape seed by SPE clean-up and GC with electron capture detection.

    PubMed

    Liu, Xiaolu; Yang, Tao; Hu, Jiye

    2013-01-01

    A method has been developed and established for residue determination of benazolin-ethyl in soil and rape seed samples by gas chromatography with electron capture detection (GC-ECD). Limits of quantification of the method are 0.005 mg/kg for both soil and rape seed, which are sufficiently below the maximum residue limit, and the limit of detection is 0.0023 ng. The average recoveries of the analyte range from 85.89 to 105.84% with relative standard deviations (coefficient of variation) less than 5.53% at the three spike levels (0.005, 0.1 and 0.5 mg/kg). The half-life of benazolin-ethyl in soil from the experimental field is 4.62 days. The final residues of benazolin-ethyl in soil and rape seed samples are lower than 0.005 mg/kg at harvest time. Direct confirmation of the analyte in real samples is achieved by GC-mass spectrometry. It is demonstrated that the proposed method is simple, rapid and efficient, and reliable to detect benazolin-ethyl residues in soil and rape seed samples. PMID:22718745

  17. Bioremediation: environmental clean-up through pathway engineering.

    PubMed

    Singh, Shailendra; Kang, Seung Hyun; Mulchandani, Ashok; Chen, Wilfred

    2008-10-01

    Given the immense risk posed by widespread environmental pollution by inorganic and organic chemicals, novel methods of decontamination and clean-up are required. Owing to the relatively high cost and the non-specificity of conventional techniques, bioremediation is a promising alternative technology for pollutant clean-up. Advances in bioremediation harness molecular, genetic, microbiology, and protein engineering tools and rely on identification of novel metal-sequestering peptides, rational and irrational pathway engineering, and enzyme design. Recent advances have been made for enhanced inorganic chemical remediation and organic chemical degradation using various pathway-engineering approaches and these are discussed in this review. PMID:18760355

  18. Simultaneous determination of a variety of endocrine disrupting compounds in carrot, lettuce and amended soil by means of focused ultrasonic solid-liquid extraction and dispersive solid-phase extraction as simplified clean-up strategy.

    PubMed

    Mijangos, L; Bizkarguenaga, E; Prieto, A; Fernández, L A; Zuloaga, O

    2015-04-10

    The present study is focused on the development of an analytical method based on focused ultrasonic solid-liquid extraction (FUSLE) followed by dispersive solid-phase extraction (dSPE) clean-up and liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS) optimised for the simultaneous analysis of certain endocrine disrupting compounds (EDCs), including alkylphenols (APs), bisphenol A (BPA), triclosan (TCS) and several hormones and sterols in vegetables (lettuce and carrot) and amended soil samples. Different variables affecting the chromatographic separation, the electrospray ionisation and mass spectrometric detection were optimised in order to improve the sensitivity of the separation and detection steps. Under the optimised extraction conditions (sonication of 5min at 33% of power with pulse times on of 0.8s and pulse times off of 0.2s in 10mL of n-hexane:acetone (30:70, v:v) mixture using an ice bath), different dSPE clean-up sorbents, such as Florisil, Envi-Carb, primary-secondary amine bonded silica (PSA) and C18, or combinations of them were evaluated for FUSLE extracts before LC-MS/MS. Apparent recoveries and precision in terms of relative standard deviation (RSDs %) of the method were determined at two different fortification levels (according to the matrix and the analyte) and values in the 70-130% and 2-27% ranges, respectively, were obtained for most of the target analytes and matrices. Matrix-matched calibration approach and the use of labelled standards as surrogates were needed for the properly quantification of most analytes and matrices. Method detection limits (MDLs), estimated with fortified samples, in the ranges of 0.1-100ng/g for carrot, 0.2-152ng/g for lettuce and 0.9-31ng/g for amended soil were obtained. The developed methodology was applied to the analysis of 11 EDCs in both real vegetable bought in a local market and in compost (from a local wastewater treatment plant, WWTP) amended soil samples. PMID:25746759

  19. Rapid estimation of readily leachable triazine residues in soils using automatic kinetic bioaccessibility assays followed by on-line sorptive clean-up as a front-end to liquid chromatography.

    PubMed

    Vida, Ana C F; Cocovi-Solberg, David J; Zagatto, Elias A G; Miró, Manuel

    2016-08-15

    An automatic batchwise bioaccessibility test was proposed for on-line monitoring of readily mobile pools of ametryn and atrazine residues in agricultural soils with different physicochemical properties. A 0.01molL(-1) CaCl2 solution mimicking rainwater percolation through the soil profiles was used for the herbicide extractions. The extract aliquots were successively sampled at regular time intervals in order to investigate the extraction kinetics. For extract clean-up and retention of freely dissolved target species, 30mg of restricted-access like copolymer were used as in-line sorptive material followed by elution with methanol and on-line heart-cut injection towards a C18 silica reversed-phase monolithic column (100×4.6mm) in a liquid chromatographic system. A mathematical model emphasized that the readily available pools vs time can be in most instances described by a first-order exponential equation, thus an asymptotical value is approached. Consequently, the leaching assays can be performed without attaining chemical equilibrium. Enhancement factors and detection limits were 10.2 and 18.8, and 0.40 and 0.37mgkg(-1) for ametryn and atrazine, respectively. The automatic method features good repeatability for leaching tests (r.s.d.: 11.8-10.2% for sandy and 3.7-6.2% for clayey soil). Reliable data, demonstrated with relative recoveries in the soil leachates ranging from 86 to 104%, were achieved in less than 35min, thus avoiding the need for up to 24h as recommended by standard leaching methods. PMID:27260437

  20. EVALUATION OF PERSONAL COOLING DEVICES FOR A DIOXIN CLEAN-UP OPERATION

    EPA Science Inventory

    The study investigated the use of personal coolers to increase worker productivity and safety while working at elevated, ambient temperatures cleaning up dioxin contaminated soil.^The study included laboratory tests to measure the thermal characteristics of the chemical protectiv...

  1. 48 CFR 52.236-12 - Cleaning Up.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Cleaning Up. 52.236-12 Section 52.236-12 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED... Cleaning Up. As prescribed in 36.512, insert the following clause: Cleaning Up (APR 1984) The...

  2. 48 CFR 52.236-12 - Cleaning Up.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Cleaning Up. 52.236-12 Section 52.236-12 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED... Cleaning Up. As prescribed in 36.512, insert the following clause: Cleaning Up (APR 1984) The...

  3. 48 CFR 52.236-12 - Cleaning Up.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Cleaning Up. 52.236-12 Section 52.236-12 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED... Cleaning Up. As prescribed in 36.512, insert the following clause: Cleaning Up (APR 1984) The...

  4. 48 CFR 52.236-12 - Cleaning Up.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Cleaning Up. 52.236-12 Section 52.236-12 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED... Cleaning Up. As prescribed in 36.512, insert the following clause: Cleaning Up (APR 1984) The...

  5. 48 CFR 52.236-12 - Cleaning Up.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Cleaning Up. 52.236-12 Section 52.236-12 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED... Cleaning Up. As prescribed in 36.512, insert the following clause: Cleaning Up (APR 1984) The...

  6. Cockroaches probably cleaned up after dinosaurs.

    PubMed

    Vršanský, Peter; van de Kamp, Thomas; Azar, Dany; Prokin, Alexander; Vidlička, L'ubomír; Vagovič, Patrik

    2013-01-01

    Dinosaurs undoubtedly produced huge quantities of excrements. But who cleaned up after them? Dung beetles and flies with rapid development were rare during most of the Mesozoic. Candidates for these duties are extinct cockroaches (Blattulidae), whose temporal range is associated with herbivorous dinosaurs. An opportunity to test this hypothesis arises from coprolites to some extent extruded from an immature cockroach preserved in the amber of Lebanon, studied using synchrotron X-ray microtomography. 1.06% of their volume is filled by particles of wood with smooth edges, in which size distribution directly supports their external pre-digestion. Because fungal pre-processing can be excluded based on the presence of large particles (combined with small total amount of wood) and absence of damages on wood, the likely source of wood are herbivore feces. Smaller particles were broken down biochemically in the cockroach hind gut, which indicates that the recent lignin-decomposing termite and cockroach endosymbionts might have been transferred to the cockroach gut upon feeding on dinosaur feces. PMID:24324610

  7. Helping nature clean up oil spills

    SciTech Connect

    Paddock, A.

    1996-11-01

    Oil spills are nothing new. In fact, for millions of years crude oil has been seeping up to the Earth`s surface, and for all that time Mother Nature has been on the job with microbes, or bacteria, to harmlessly convert the oil to water and carbon dioxide gas. Not all bacteria are bad. True, some can make us sick, however, the good ones help us bake bread, brew beer, and even clean up oil spills by a process known as biodegradation. Oil and bacteria don`t easily get together because oil and water don`t mix and bacteria prefer to stay in water. After some oil tankers spills in the English Channel 25 years ago, major oil companies (Arco, BP, Exxon, and others) developed oil dispersant products-specialized chemicals that make oils and sea water mix. The simplest examples of similar wetting agents are soaps and detergents. Now, thanks to dispersants, the natural bacteria at sea can easily get to the oil and the normally slow biodegradation process goes rather quickly.

  8. Cockroaches Probably Cleaned Up after Dinosaurs

    PubMed Central

    Vršanský, Peter; van de Kamp, Thomas; Azar, Dany; Prokin, Alexander; Vidlička, L'ubomír; Vagovič, Patrik

    2013-01-01

    Dinosaurs undoubtedly produced huge quantities of excrements. But who cleaned up after them? Dung beetles and flies with rapid development were rare during most of the Mesozoic. Candidates for these duties are extinct cockroaches (Blattulidae), whose temporal range is associated with herbivorous dinosaurs. An opportunity to test this hypothesis arises from coprolites to some extent extruded from an immature cockroach preserved in the amber of Lebanon, studied using synchrotron X-ray microtomography. 1.06% of their volume is filled by particles of wood with smooth edges, in which size distribution directly supports their external pre-digestion. Because fungal pre-processing can be excluded based on the presence of large particles (combined with small total amount of wood) and absence of damages on wood, the likely source of wood are herbivore feces. Smaller particles were broken down biochemically in the cockroach hind gut, which indicates that the recent lignin-decomposing termite and cockroach endosymbionts might have been transferred to the cockroach gut upon feeding on dinosaur feces. PMID:24324610

  9. Interim Site Assessment and Clean-up Guidebook

    SciTech Connect

    Elliott, K.L.

    1996-12-31

    In April 1995 an Interim Site Investigation and Clean-up Guidebook (for petroleum hydrocarbon and volatile organic compound impacted sites) was developed for public use. The purpose of the Guidebook was to offer a new approach to the site cleanup process: one that reduces time, cuts costs, and establishes a defined endpoint for investigations and cleanup actions. The Guidebook provided a matrix to screen for low-risk contaminated sites. After a year of use, the Guidebook was revised in May 1996. The most notable change was in the Petroleum Hydrocarbon Section and the modification of the screening table for petroleum hydrocarbon contaminated sites. The changes considered the strong influence of lithology on contaminant transport and recognized the large attenuation of the long chain, heavy oil and tar, hydrocarbons in soils.

  10. Cleaning up the nuclear weapons complex: A herculean challenge

    SciTech Connect

    Probst, K.N.; McGovern, M.H.

    1996-12-31

    For nearly five decades, the US Department of Energy (DOE) and its predecessors engaged in a highly secretive, complex, and massive endeavor to fabricate nuclear weapons for national security purposes. Large-scale production of nuclear weapons was an unprecedented undertaking requiring thousands of facilities, dozens of large tracts of land, huge volumes of dangerous materials, and great quantities of water. With the Cold Wars end and the emergence of new types of national security concerns, weapons production operations have, for the most part, ceased, and much of the secrecy under which they were shrouded has lifted. The subsequent revelation reveal at many sites tremendous volumes of soil and groundwater are contaminated with both radioactive and hazardous materials. Wastes stored for years pose substantial dangers, and many aging facilities that harbor highly radioactive and sensitive materials are deteriorating. The topics covered in this overview article include the following: more to `cleanup` than cleaning up; a fragmented regulatory regime; new regulatory regimes.

  11. Glufosinate ammonium clean-up procedure from water samples using SPE

    NASA Astrophysics Data System (ADS)

    Tayeb M., A.; Ismail B., S.; Mardiana-Jansar, K.; Ta, Goh Choo; Agustar, Hani Kartini

    2015-09-01

    For the determination of glufosinate ammonium residue in soil and water samples, different solid phase extraction (SPE) sorbent efficiency was studied. Four different SPE sorbents i.e.: CROMABOND PS-H+, CROMABOND PS-OH-, ISOLUTE ENV+, Water Sep-Pak and OASIS HLB were used. Sample clean-up performance was evaluated using high performance liquid chromatography (Agilent 1220 infinity LC) with fluorescence detector. Detection of FMO-derivatives was done at λ ex = 260 nm and λ em= 310 nm. OASIS HLB column was the most suitable for the clean-up in view of the overall feasibility of the analysis.

  12. 40 CFR 263.31 - Discharge clean up.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS APPLICABLE TO TRANSPORTERS OF HAZARDOUS WASTE Hazardous Waste Discharges § 263.31 Discharge clean up. A transporter must clean up any hazardous waste discharge that occurs during transportation...

  13. 40 CFR 263.31 - Discharge clean up.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Discharge clean up. 263.31 Section 263.31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... up. A transporter must clean up any hazardous waste discharge that occurs during transportation...

  14. 40 CFR 263.31 - Discharge clean up.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Discharge clean up. 263.31 Section 263.31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... up. A transporter must clean up any hazardous waste discharge that occurs during transportation...

  15. 40 CFR 263.31 - Discharge clean up.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Discharge clean up. 263.31 Section 263.31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... up. A transporter must clean up any hazardous waste discharge that occurs during transportation...

  16. 40 CFR 263.31 - Discharge clean up.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Discharge clean up. 263.31 Section 263.31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... up. A transporter must clean up any hazardous waste discharge that occurs during transportation...

  17. Using Phytoremediation to Clean Up Contamination at Military Installations

    SciTech Connect

    Zellmer, S.D.; Hinchman, R.R.; Negri, M.C.; Schneider, J.F.; Gatliff, E.G.

    1997-07-01

    During and following World War II, wastes from the production of munitions and other military materials were disposed of using the best available practices acceptable at that time. However, these disposal methods often contaminated soil and groundwater with organic compounds and metals that require cleanup under current regulations. An emerging technology for cleaning contaminated soils and shallow groundwater is phytoremediation, an environmentally friendly, low- cost, and low-tech process. Phytoremediation encompasses all plant- influenced biological, chemical, and physical processes that aid in the uptake, degradation, and metabolism of contaminants by either plants or free-living organisms in the plant`s rhizosphere. A phytoremediation system can be viewed as a biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the soil and below-ground ecosystem for subsequent productive use. Argonne National Laboratory (ANL) has been conducting basic and applied research in phytoremediation since 1990. Initial greenhouse studies evaluated salt-tolerant wetland plants to clean UP and reduce the volume of salty `produced water` from petroleum wells. Results of these studies were used to design a bioreactor for processing produced water that is being demonstrated at a natural gas well in Oklahoma; this system can reduce produced water volume by about 75% in less than eight days, representing substantial savings in waste disposal cost. During 1994, ANL conducted a TNT plant uptake and in situ remediation study in a ridge-and-furrow area used for the disposal of pink water at the Joliet Army Ammunition Plant.

  18. PRP: The Proven Solution for Cleaning Up Oil Spills

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The basic technology behind PRP is thousands of microcapsules, tiny balls of beeswax with hollow centers. Water cannot penetrate the microcapsule s cell, but oil is absorbed right into the beeswax spheres as they float on the water s surface. This way, the contaminants, chemical compounds that originally come from crude oil such as fuels, motor oils, or petroleum hydrocarbons, are caught before they settle. PRP works well as a loose powder for cleaning up contaminants in lakes and other ecologically fragile areas. The powder can be spread over a contaminated body of water or soil, and it will absorb contaminants, contain them in isolation, and dispose of them safely. In water, it is important that PRP floats and keeps the oil on the surface, because, even if oil exposure is not immediately lethal, it can cause long-term harm if allowed to settle. Bottom-dwelling fish exposed to compounds released after oil spills may develop liver disease, in addition to reproductive and growth problems. This use of PRP is especially effective for environmental cleanup in sensitive areas like coral reefs and mangroves.

  19. 36. HISTORIC PHOTOGRAPH SHOWING BILL KEYS CLEANING UP AFTER THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. HISTORIC PHOTOGRAPH SHOWING BILL KEYS CLEANING UP AFTER THE MILL RUN (NOTE SCREEN FROM MORTAR SETTING ON TABLE, STAMPS ARE HUNG UP). - Wall Street Gold Mill, Twentynine Palms, San Bernardino County, CA

  20. ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL

    SciTech Connect

    Ernie F. Stine

    2002-08-14

    E&I. The company will be denoted as ''IT'' for the rest of the document since the original contract was awarded to IT. This report details IT, Knoxville, TN and its subcontractor Nuclear Fuels Services (NFS) study to investigate alternative mercury treatment technology. The IT/NFS team demonstrated two processes for the amalgamation/stabilization/fixation of mercury and potentially Resource Conservation Recovery Act (RCRA) and radionuclide-contaminated soils. This project was to identify and demonstrate remedial methods to clean up mercury-contaminated soil using established treatment chemistries on soil from the Oak Ridge Reservation, Y-12 National Security Complex, the off-site David Witherspoon properties, and/or other similarly contaminated sites. Soil from the basement of Y-12 Plant Alpha 2 Building at the Oak Ridge Reservation was received at IT and NFS on December 20, 2001. Soils from the other locations were not investigated. The soil had background levels of radioactivity and had all eight RCRA metals well below the Toxicity Characteristic (TC) criteria. This project addresses the new DOE Environmental Management Thrust 2 ''Alternative Approaches to Current High Risk/High Cost Baselines''. Successful completion of this project will provide a step-change in DOE's treatment ability.

  1. ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL

    SciTech Connect

    Ernest F. Stine Jr; Steven T. Downey

    2002-08-14

    U.S. Department of Energy (DOE) used large quantities of mercury in the uranium separating process from the 1950s until the late 1980s in support of national defense. Some of this mercury, as well as other hazardous metals and radionuclides, found its way into, and under, several buildings, soil and subsurface soils and into some of the surface waters. Several of these areas may pose potential health or environmental risks and must be dealt with under current environmental regulations. DOE's National Energy Technology Laboratory (NETL) awarded a contract ''Alternative Field Methods to Treat Mercury in Soil'' to IT Group, Knoxville TN (IT) and its subcontractor NFS, Erwin, TN to identify remedial methods to clean up mercury-contaminated high-clay content soils using proven treatment chemistries. The sites of interest were the Y-12 National Security Complex located in Oak Ridge, Tennessee, the David Witherspoon properties located in Knoxville, Tennessee, and at other similarly contaminated sites. The primary laboratory-scale contract objectives were (1) to safely retrieve and test samples of contaminated soil in an approved laboratory and (2) to determine an acceptable treatment method to ensure that the mercury does not leach from the soil above regulatory levels. The leaching requirements were to meet the TC (0.2 mg/l) and UTS (0.025 mg/l) TCLP criteria. In-situ treatments were preferred to control potential mercury vapors emissions and liquid mercury spills associated with ex-situ treatments. All laboratory work was conducted in IT's and NFS laboratories. Mercury contaminated nonradioactive soil from under the Alpha 2 building in the Y-12 complex was used. This soils contained insufficient levels of leachable mercury and resulted in TCLP mercury concentrations that were similar to the applicable LDR limits. The soil was spiked at multiple levels with metallic (up to 6000 mg/l) and soluble mercury compounds (up to 500 mg/kg) to simulate expected ranges of mercury

  2. Optimizing anaerobic soil disinfestation: an alternative to soil fumigation?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil disinfestation methods using anaerobic decomposition of organic matter were developed in the Netherlands and Japan as an ecological alternative to MeBr. Anaerobic soil disinfestation (ASD) works by creating a combination of anaerobic soil conditions and readily available carbon pools to stimula...

  3. Marine Debris Clean-Ups as Meaningful Science Learning

    ERIC Educational Resources Information Center

    Stepath, Carl M.; Bacon, Joseph Scott

    2010-01-01

    This seven to eight week hands-on Marine Debris Clean-up Project used a service project to provide an introduction of marine science ecology, watershed interrelationships, the scientific method, and environmental stewardship to 8th grade middle school students. It utilized inquiry based learning to introduce marine debris sources and impacts to…

  4. Robotic soil sampler for hazardous waste clean up

    SciTech Connect

    Jaselskis, E.J.

    1992-01-01

    An innovative field sampling system using LA-ICP-AES (laser ablation-inductively coupled plasma -- atomic emission spectrometry) technology is currently being developed through an integrated team approach at Ames Laboratory to provide in-situ, real time analysis of inorganic hazardous waste. This sampling approach is conducted through a mobile testing facility which consists of an instrumentation vehicle called the Mobile Demonstration Laboratory for Environmental Screening Technologies (MDLEST), and an attached trailer called the Robotic Sampling Accessory (RSA). The RSA provides automated sampling capabilities through an attached three-degree-of-freedom robot that will be equipped with surface and subsurface sampling probes. The probes are currently being designed by a multidisciplinary team consisting of engineers and scientists at Ames Laboratory, Iowa State University, and Lockheed. This system is expected to improve sample quality assurance, reduce sampling time and cost, and improve worker safety. Limitations and future areas of research for the MDLEST-RSA are also discussed.

  5. Robotic soil sampler for hazardous waste clean up

    SciTech Connect

    Jaselskis, E.J.

    1992-06-01

    An innovative field sampling system using LA-ICP-AES (laser ablation-inductively coupled plasma -- atomic emission spectrometry) technology is currently being developed through an integrated team approach at Ames Laboratory to provide in-situ, real time analysis of inorganic hazardous waste. This sampling approach is conducted through a mobile testing facility which consists of an instrumentation vehicle called the Mobile Demonstration Laboratory for Environmental Screening Technologies (MDLEST), and an attached trailer called the Robotic Sampling Accessory (RSA). The RSA provides automated sampling capabilities through an attached three-degree-of-freedom robot that will be equipped with surface and subsurface sampling probes. The probes are currently being designed by a multidisciplinary team consisting of engineers and scientists at Ames Laboratory, Iowa State University, and Lockheed. This system is expected to improve sample quality assurance, reduce sampling time and cost, and improve worker safety. Limitations and future areas of research for the MDLEST-RSA are also discussed.

  6. Myelodysplastic syndromes in Chernobyl clean-up workers.

    PubMed

    Gluzman, Daniil F; Sklyarenko, Lilia M; Koval, Stella V; Rodionova, Nataliia K; Zavelevich, Michael P; Ivanivskaya, Tetiana S; Poludnenko, Liudmyla Yu; Ukrainskaya, Nataliia I

    2015-10-01

    The studies of the recent decades posed the question of the association between radiation exposure and myelodysplastic syndromes (MDS). This association has been proved in secondary MDS originating upon exposure to chemotherapeutics and/or radiation therapy. The long-term study in Japanese atomic (A)-bomb survivors demonstrated the significant linear dose-response for MDS confirming the link between radiation exposure and this form of hematopoietic malignancies. All these findings provide the strong basis for studying MDS in the persons exposed to radiation following the Chernobyl disaster, especially those in the cohort of Chernobyl clean-up workers of 1986-1987. The data on MDS among Chernobyl clean-up workers (1986-1987) diagnosed in 1996-2012 at the reference laboratory of RE Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology are summarized. MDS cases were diagnosed in 23 persons (21 males and 2 females) having been exposed to radiation as clean-up workers of 1986-1987. Refractory anemia (RA) has been detected in 13, refractory anemia with ring sideroblasts (RARS)-in 2, and refractory anemia with excess blasts (RAEB)-in 8 patients. The median age of those MDS patients was 62.0 years. In addition, 5 cases of chronic myelomonocytic leukemia (CMML) were recorded in the group of Chernobyl clean-up workers with the median time of 14.8 years from 1986-1987 to diagnosis. The association between radiation exposure and MDS is discussed. The suggested life-long risk for myelodysplastic syndromes among A-bomb survivors in Japan highlights the importance of the continuing follow-up studies in the affected populations in the post-Chernobyl period. PMID:26208666

  7. Clean-up of Nuclear Licensed Facility 57

    SciTech Connect

    Jeanjacques, Michel; Bremond, Marie Pierre; Marchand, Carole; Poyau, Cecile; Viallefont, Cecile; Gautier, Laurent; Masure, Frederic

    2007-07-01

    Available in abstract form only. Full text of publication follows: In the early sixties a radiochemistry laboratory dedicated to Research and Development was built at the French Atomic Energy Commission's centre at Fontenay aux Roses (CEA-FAR); it was named Building 18. More buildings were added during the decade: Building 54, storehouses and offices and Building 91, a hall and laboratories for chemical engineering research into natural and depleted uranium. These three buildings together constitute NLF57. Construction work took place between 1959 and 1962 and the buildings entered operation in 1961. The research and development programs performed in NLF57 involved spent fuel reprocessing studies, waste treatment processes and studies and production of transuranic elements with the related analytical methods development. The research and development program ended on 30 June 1995. The NLF57 clean-up program was launched to reduce the nuclear and conventional hazards and minimise HLW and MLW production during the dismantling work. The clean-up work was divided into categories by type to facilitate its organisation: treatment and removal of nuclear material, removal of radioactive sources, treatment and removal of organic and aqueous effluents, treatment and removal of solid waste, pumping out of the PETRUS tank, flushing and decontamination of the tanks and clean-up of buildings. (authors)

  8. Tidd hot gas clean up program. Final report

    SciTech Connect

    1995-10-01

    This Final Report on the Tidd Hot Gas Clean Up Program covers the period from initial Proof-of-Concept testing in August, 1990, through final equipment inspections in May, 1995. The Tidd Hot Gas Clean Up (HGCU) system was installed in the Tidd Pressurized Fluidized Bed Combustion (PFBC) Demonstration Plant, which is the first utility-scale PFBC plant in the United States. Detailed design work on the project began in July, 1990, and site construction began in December, 1991. Initial operation of the system occurred in May, 1992, and the hot gas filter was commissioned in October, 1992. The test program ended in March, 1995, when the Tidd Plant was shut down following its four-year test program. Section 1.0 of this report is an executive summary of the project covering the project background, system description, test results and conclusions. Section 2.0 is an introduction covering the program objectives and schedule. Section 3.0 provides detailed descriptions of the system and its major components. Section 4.0 provides detailed results of all testing including observations and posttest inspection results. Sections 5.0 and 6.0 list the program conclusions and recommendations, respectively. Appendix I is a report prepared by Southern Research Institute on the properties of Tidd PFBC ash sampled during the test program. Appendix II is a report prepared by Westinghouse STC on the performance of candle filter fail-safe regenerator devices.

  9. Recent trends at the state and federal level in accelerating CERCLA clean-ups

    SciTech Connect

    Clegg, B.

    1996-12-31

    Efforts at accelerating remedial action at the federal level focus on the following: the Superfund accelerated clean-up model (SCAM); Brownfields economic redevelopment initiative; guidance documents and policies; and collaboration with state voluntary cleanup programs. At the state level efforts involved in accelerating clean-ups include voluntary clean-up programs and Brownfields initiatives.

  10. Hudson River PCB clean-up to begin

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    U.S. Environmental Protection Agency Administrator Christie Whitman signed the Record of Decision on 1 February to clean up a stretch of the Hudson River that has been contaminated by polychlorinated biphenyls (PCBs). The decision calls for dredging 2 million cubic meters of PCB-contaminated sediment from a 64-kilometer stretch of the upper Hudson to remove about 68,000 kilograms of PCBs.The plan follows years of scientific study about whether the PCBs were safely encased in the sediment or posed a continuing hazard, and concern over whether the PCBs can be safely removed without stirring up a larger pollution problem along the river. The EPA found that PCBs in the sediment are not safely buried because erosion and river flows can redistribute river sediment. The agency also found that although PCBs break down naturally over time, this degradation does not render them harmless.

  11. Predicting soil erosion for alternative land uses.

    PubMed

    Wang, Erda; Xin, Chang; Williams, Jimmy R; Xu, Cheng

    2006-01-01

    The APEX (Agricultural Policy-Environmental eXtender) model developed in the United States was calibrated for northwestern China's conditions. The model was then used to investigate soil erosion effects associated with alternative land uses at the ZFG (Zi-Fang-Gully) watershed in northwestern China. The results indicated that the APEX model could be calibrated reasonably well (+/-15% errors) to fit those areas with >50% slope within the watershed. Factors being considered during calibration include runoff, RUSLE (Revised Universal Soil Loss Equation) slope length and steepness factor, channel capacity flow rate, floodplain saturated hydraulic conductivity, and RUSLE C factor coefficient. No changes were made in the APEX computer code. Predictions suggest that reforestation is the best practice among the eight alternative land uses (the status quo, all grass, all grain, all grazing, all forest, half tree and half grass, 70% tree and 30% grain, and construction of a reservoir) for control of water runoff and soil erosion. Construction of a reservoir is the most effective strategy for controlling sediment yield although it does nothing to control upland erosion. For every 1 Mg of crop yield, 11 Mg of soil were lost during the 30-yr simulation period, suggesting that expanding land use for food production should not be encouraged on the ZFG watershed. Grass species are less effective than trees in controlling runoff and erosion on steep slopes because trees generally have deeper and more stable root systems. PMID:16455846

  12. Bioenergy residues as novel sorbents to clean up pesticide pollution

    NASA Astrophysics Data System (ADS)

    Mukherjee, Santanu

    2016-04-01

    Worldwide, water contamination from agricultural use of pesticides has received increasing attention within the last decades. In general, sources of pesticide water pollution are categorized into diffuse (stemming from treated fields) and point sources (stemming from farmyards and spillages). Research has demonstrated that 40 to 90% of surface water pesticide contamination is due to point source pollution. To reduce point pollution from farm yards, where the spray equipment is washed, biobed or biofilter systems are used to treat the washing water. The organic material usually used in these systems is often not environmentally sustainable (e.g. peat) and incorporated organic material such as straw leads to a highly heterogeneous water flow, with negative effects on the retention and degradation behavior of the pesticides. Therefore, the objective of this study was to assess the suitability of alternative materials based on bioenergy residues (biochar and digestate) for use in biofilters. To this aim the sorption-desorption potential of three contrasting pesticides (bentazone, boscalid, and pyrimethanil) on mixtures of soil with digestate and/or biochar were investigated in laboratory batch equilibrium experiments. The results indicate that the mixture of digestate and biochar increased pesticide sorption potential, whereby in all cases, the Kd des / Kf des values were lower than the Kd ads / Kf ads values indicating that the retention of the pesticides was weak. Thus, as Kf des were lower than the Kf ads values and H values were below 1, it can be concluded that the biomixtures presented negative desorption (higher hysteresis) in those cases. A higher Kd (>78 L kg-1), Kf (>400 μM1-1/nf L1/nfkg-1) and KL (>40 L kg-1) was obtained for all pesticides for the digestate and biochar based mixtures, which had a higher organic matter content. However, lower sorption of the pesticides was observed in blank soil compared to the other biomixtures, which was attributed to the

  13. Acetonitrile extraction and dual-layer solid phase extraction clean-up for pesticide residue analysis in propolis.

    PubMed

    Oellig, Claudia

    2016-05-01

    Propolis is a very complex mixture of substances that is produced by honey bees and is known to be a rather challenging matrix for residue analysis. Besides resins, flavonoids and phenols, high amount of wax is co-extracted resulting in immense matrix effects. Therefore a suitable clean-up is crucial and indispensable. In this study, a reliable solid phase extraction (SPE) clean-up was developed for pesticide residue analysis in propolis. The clean-up success was quickly and easily monitored by high-performance thin-layer chromatography with different detection possibilities. The final method consists of the extraction of propolis with acetonitrile according to the QuEChERS method followed by an effective extract purification on dual-layer SPE cartridges with spherical hydrophobic polystyrene-divinylbenzene resin/primary secondary amine as sorbent and a mixture of toluene/acetone (95:5, v/v) for elution. Besides fat-soluble components like waxes, flavonoids, and terpenoids, more polar compounds like organic acids, fatty acids, sugars and anthocyanins were also removed to large extent. Method performance was assessed by recovery experiments at spiking levels of 0.5 and 1mg/kg (n=5) for fourteen pesticides that are relevant for propolis. Mean recoveries determined by HPLC-MS against solvent standards were between 40 and 101%, while calculation against matrix-matched standards provided recoveries of 79-104%. Precision of recovery, assessed by relative standard deviations, were below 9%. Thus, the developed dual-layer SPE clean-up enables the reliable pesticide residue analysis in propolis and provides a suitable alternative to time-consuming clean-up procedures proposed in literature. PMID:27059398

  14. Sulfide clean-up of solutions from heavy metal ions

    SciTech Connect

    Kislinskaya, G.E.; Kozachek, N.N.; Krasnova, G.M.; Shenk, N.I.

    1982-09-20

    The object of the present research was to determine the conditions for thorough clean-up of solutions from cadmium or mercury contamination by use of iron sulfide. Results indicated that the shape of the dependence of the degree of extraction of copper with iron sulfide on the pH value is analogous to the curve for cadmium; that is, copper, like cadmium, is precipitated by chemical reaction. In distinction from cadmium and copper, mercury is extracted by iron sulfide both in acid and also in neutral solutions, that is, it is possible to attain a direct ion exchange by reaction. At high pH values, only small amounts of iron go into solution, therefore FeS can be used very rationally for the extraction of both small (about 1 mg/liter), and also of large (about 1 mg/liter) amounts of mercury from solutions, which are nearly neutral. By adding sodium sulfide and a flocculant, one can accelerate the process of mercury precipitation, and also reduce the solution of iron sulfide. In the present case, iron sulfide plays the role of a substrate for the crystallization of mercury sulfide, since in dilute solutions the latter forms poorly filterable colloidal solutions. Thus when one uses fused iron sulfide with addition of sodium sulfide, a high degree of mercury extraction is attained, and the spent sorbent is filtered well.

  15. Environmental benefits of Boston Harbor clean-up projects

    SciTech Connect

    Connor, M.S.; Smith, W.M. )

    1990-01-09

    The Massachusetts Water Resources Authority has undertaken one of the largest public works projects in the country to control the pollution of Boston Harbor. The project includes construction of a new primary and secondary treatment plant and sludge treatment facilities, excavation of a long ocean outfall and diffuser, and a solution to the overflow of mixed sewage and stormwater during storms; it will take over twenty years and billions of dollars to construct. A comparison of the relative costs and environmental benefits of relative costs and environmental benefits of the various construction projects, and other pollution control strategies, shows that some projects are more cost-effective than others for solving specific pollution problems. The capture and treatment of combined sewer overflow (CSO) will result in a more dramatic reduction of pathogen contamination than will completion of the primary and secondary treatment plants. Although the flow of raw sewage is intermittent and relatively small, it has high concentrations of bacteria and viruses. On the other hand, the new treatment plants will be more important in reducing toxic contamination of fish and shellfish. In summary, all the planned clean-up projects appear to be necessary to reach the goal of a swimmable, fishable Boston Harbor.

  16. Building upon Historical Competencies: Next-generation Clean-up Technologies for World-Wide Application - 13368

    SciTech Connect

    Guevara, K.C.; Fellinger, A.P.; Aylward, R.S.; Griffin, J.C.; Hyatt, J.E.; Bush, S.R.

    2013-07-01

    The Department of Energy's Savannah River Site has a 60-year history of successfully operating nuclear facilities and cleaning up the nuclear legacy of the Cold War era through the processing of radioactive and otherwise hazardous wastes, remediation of contaminated soil and groundwater, management of nuclear materials, and deactivation and decommissioning of excess facilities. SRS recently unveiled its Enterprise.SRS (E.SRS) strategic vision to identify and facilitate application of the historical competencies of the site to current and future national and global challenges. E.SRS initiatives such as the initiative to Develop and Demonstrate Next generation Clean-up Technologies seek timely and mutually beneficial engagements with entities around the country and the world. One such ongoing engagement is with government and industry in Japan in the recovery from the devastation of the Fukushima Daiichi Nuclear Power Station. (authors)

  17. Ecologically-based clean-up criteria for nitroaromatic explosives using toxicity test results

    SciTech Connect

    Duh, D.; Roberts, B.; Buzgo, S.

    1995-12-31

    A former trinitrotoluene (TNT) production and storage facility was the focus of a Remedial Investigation (RI). Contaminants identified during the RI included 2,4-dinitrotoluene (DNT), 2,6-DNT, and 2,4,6-TNT, PCBs, arsenic, lead and chromium. The Conceptual Site Model determined there to be several complete exposure pathways. One of these identified a route by which soil invertebrate communities could be affected through dermal contact and ingestion of soil contaminants. Maintenance of the soil invertebrate community was chosen as the assessment endpoints for this pathway in the Ecological Risk Assessment. The corresponding measurement endpoint was survival of earthworms in 14-day toxicity tests in which they were exposed to site soils. Seven surficial soil samples were collected from Areas of Concern. Each sample was evaluated for acute toxicity to earthworms using standard USEPA protocols. Chemical concentrations were also measured. An artificial soil was used as the control and diluent to establish the Lethal Concentration (LC{sub 50}) of the test soils to earthworms. From the toxicity test results and the corresponding chemical analysis, a matrix of toxicity and contaminant levels was developed. This table was used to determine a concentration of each contaminant at which no acute lethality would be expected. Lower bounds to the chemical specific LC{sub 50} values were determined and, based on sample-specific toxicity units, appropriate LC{sub 50} values were derived (333 mg/kg 2,4-DNT, 182 mg/kg 2,6-DNT, and 1960 mg/kg 2,4,6TNT). Extrapolation of this level to a chronic No Observable Adverse Effect Level (NOAEL) provided a means of proposing site-specific ecologically based clean-up criteria for the constituents of concern which would be protective of the chosen assessment endpoint.

  18. BIOREMEDIATION OF CONTAMINATED SURFACE SOILS

    EPA Science Inventory

    Biological remediation of soils contaminated with organic chemicals is an alternative treatment technology that can often meet the goal of achieving a permanent clean-up remedy at hazardous waste sites, as encouraged by the U.S. Environmental Protection Agency (U.S. EPA) for impl...

  19. 75 FR 26098 - Safety Zone; Under Water Clean Up of Copper Canyon, Lake Havasu, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Under Water Clean Up of Copper Canyon, Lake... Clean up, which will involve 40 divers cleaning the river bottom in Lake Havasu. The Coast Guard is... responsibilities between the Federal Government and Indian tribes. Energy Effects We have analyzed this rule...

  20. 25 CFR 170.906 - Who cleans up radioactive and hazardous material spills?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Who cleans up radioactive and hazardous material spills... § 170.906 Who cleans up radioactive and hazardous material spills? The carrier is typically responsible for cleanup of a radioactive or hazardous material spill with assistance from the shipper...

  1. 25 CFR 170.906 - Who cleans up radioactive and hazardous material spills?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Who cleans up radioactive and hazardous material spills... § 170.906 Who cleans up radioactive and hazardous material spills? The carrier is typically responsible for cleanup of a radioactive or hazardous material spill with assistance from the shipper...

  2. 25 CFR 170.906 - Who cleans up radioactive and hazardous material spills?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Who cleans up radioactive and hazardous material spills... § 170.906 Who cleans up radioactive and hazardous material spills? The carrier is typically responsible for cleanup of a radioactive or hazardous material spill with assistance from the shipper...

  3. 25 CFR 170.906 - Who cleans up radioactive and hazardous material spills?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Who cleans up radioactive and hazardous material spills... § 170.906 Who cleans up radioactive and hazardous material spills? The carrier is typically responsible for cleanup of a radioactive or hazardous material spill with assistance from the shipper...

  4. 25 CFR 170.906 - Who cleans up radioactive and hazardous material spills?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Who cleans up radioactive and hazardous material spills... § 170.906 Who cleans up radioactive and hazardous material spills? The carrier is typically responsible for cleanup of a radioactive or hazardous material spill with assistance from the shipper...

  5. An investigation of critical parameters for optimum perforation clean-up

    SciTech Connect

    Hovem, K.; Joeranson, H.; Espedal, A.; Wilson, S.

    1995-12-31

    Field data presented in the paper suggest that an open-choke perforating practice improves perforation clean-up. An experimental and numerical investigation of this technique confirmed that an open-choke perforating practice leads to higher core flow efficiency compared to closed-choke perforating with subsequent clean-up flow.

  6. 76 FR 70170 - Proposed Alternative Soils Standards for the Uravan, Colorado Uranium Mill

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-10

    ... COMMISSION Proposed Alternative Soils Standards for the Uravan, Colorado Uranium Mill AGENCY: Nuclear... Waste Management Division (the Division) submitted a proposal for alternative standards for soil clean...) concurrence. Colorado's proposed alternative soil standards are to leave the remaining...

  7. Photochemical sample treatment for extracts clean up in PCB analysis from sediments.

    PubMed

    Barreca, Salvatore; Orecchio, Santino; Pace, Andrea

    2013-01-15

    Sample purification can be considered the most polluting step of the whole analytical process for PCBs determination in sediment samples. The use of photochemical sample treatment represents an alternative methodology for extracts clean up allowing for a reduction of the used amount of organic solvents. The first application of a photochemical sample treatment for the selective removal or reduction of organic substances interfering with PCBs analyses in sediments is reported. The method's efficiency and robustness were compared with currently used chromatographic purification. Quality parameters such as recovery, linearity and reproducibility were studied. The entire procedure was validated by four replicate analysis of certified reference sediment. The quantification limits (LOQ) obtained by us ranged from 1 to 3.1 ng g(-1). The RSD for each congener was below 15% and recoveries were in the range 40-130%. Results based on the analysis of real and certified samples showed similar or improved detection thresholds and pointed out the advantages of the photochemical methodology in terms of costs and environmental friendly conditions. PMID:23200398

  8. Attitudes toward managing hazardous waste: What should be cleaned up and who should pay for it

    SciTech Connect

    Baron, J.; Kunreuther, H. ); Gowda, R. )

    1993-04-01

    Hazardous waste policy in the United States uses a liability-based approach, including strict, retroactive, and joint and several liability. To assess attitudes toward these basic principles of liability, and toward priorities for clean-up of wastes, a questionnaire was mailed to legislators, judges, executives of oil and chemical companies, environmentalists, and economists. The questionnaire consisted of abstract, simplified cases, which contrasted basic principles rather than dealing with real-world scenarios. Subjects were asked how they would allocate clean-up costs between companies and government as a function of such factors as adherence to standards, adoption of best available technology (BAT), and influence of penalties on future behavior. Most subjects felt that, if the company followed government standards or used the best available technology (BAT), it should pay for only a portion of the clean-up cost, with the government paying the rest. In general, responses did not support the principles underlying current law - strict, retroactive, and joint-and-several liability. Most subjects were more interested in polluters paying for damages than in deterrence or future benefit - even to the extent that they would have harmless' waste sites cleaned up. A bias was found toward complete clean-up of some sites, or zero risk.' Different groups of subjects gave similar answers, although more committed environmentalists were more willing to make companies pay and to clean up waste regardless of the cost. 21 refs., 3 tabs.

  9. The Fate of Alternative Soil Funigants to Methyl Bromide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil fumigation is an important agricultural practice for the control of soil-borne pests. Since the phase–out of methyl bromide, due to its role in the depletion of stratospheric ozone, several alternatives such as 1,3-dichloropropene (1,3-D), chloropicrin (CP), and dimethyl disulfide (DMDS) are b...

  10. The 7% Solution - Cleaning Up After Fred Vine's Outstanding Successes

    NASA Astrophysics Data System (ADS)

    Hey, R. N.

    2013-12-01

    asymmetry increases towards Iceland where we had the great advantage of working), & contrary to conventional wisdom the V-shaped ridges, scarps & troughs (VSRs) discovered by Peter Vogt are not symmetric about the Reykjanes Ridge axis. Analysis of magnetic anomaly data from our 2007 expedition by Benediktsdóttir et al. shows these asymmetries were created by rift propagation both away from & towards Iceland, suggesting a tectonic alternative to the magmatic pulsing plume explanation for the VSRs. These results further suggest that the massive transform-eliminating North Atlantic plate boundary reorganization that created the linear obliquely-spreading Reykjanes Ridge might also be a propagating rift phenomenon instead of a thermal phenomenon as generally assumed, & we hope to present results from a new Reykjanes Ridge expedition later this summer designed to determine exactly how this reorganization is occurring. That so much research for several decades has resulted from the small (the 7% number in the title is made up - inspired by Fred I never did learn statistics) modification of Fred's results is a tribute to the overwhelming success of seafloor spreading & plate tectonics. Unfortunately for Vine, Morgan & McKenzie, this scientific revolution appears to have been too profound for Nobel Prizes.

  11. Biological quality of soils containing hydrocarbons and efficacy of ecological risk reduction by bioremediation alternatives

    SciTech Connect

    Stewart, A.J.; Napolitano, G.E.; Sample, B.E.

    1996-06-01

    This project provides technical support to the Petroleum Environmental Research Forum (PERF; a consortium of petroleum companies) on environmentally acceptable endpoints that may be used to help assess the ecological risk of petroleum hydrocarbon residuals in soils. The project, was designed in consultation with PERF representatives and focuses on the relationship between {open_quotes}chemically available{close_quotes} and {open_quotes}biologically available{close_quotes} measurements of petroleum hydrocarbon compounds in soils, a discrepancy of considerable interest to the petroleum industry. Presently, clean-up standards for soils contaminated with total petroleum hydrocarbon (TPH) constituents are based on concentrations of TPH, as measured in solvent extracts of soil samples. Interestingly, TPH includes a complex mixture of compounds which differ from one another in molecular weight and toxicity. Based on various studies with insecticides, herbicides and metals, some compounds apparently can slowly permeate into soil particles. If this situation occurs, the particle-embedded compounds may be extractable by use of organic solvents, and yet be unavailable biologically. This hypothesis serves as the central focus for our study. If this hypothesis is correct, then soil clean-up standards based on solvent-extractable TPH data may be more stringent than necessary to achieve a desired level of environmental risk. The economic significance of this possibility is considerable, because clean-up costs to achieve a low-risk status would, in most cases, be lower than those needed to achieve a standard based on present limits, which are based on measurements of {open_quotes}extractable{close_quotes} TPH.

  12. An alternative to soil taxonomy for describing key soil characteristics

    USGS Publications Warehouse

    Duniway, Michael C.; Miller, Mark E.; Brown, Joel R.; Toevs, Gordon

    2013-01-01

    is not a simple task. Furthermore, because the US system of soil taxonomy is not applied universally, its utility as a means for effectively describing soil characteristics to readers in other countries is limited. Finally, and most importantly, even at the finest level of soil classification there are often large within-taxa variations in critical properties that can determine ecosystem responses to drivers such as climate and land-use change.

  13. Denitrification: a Clean-Up Mechanism for High Nitrate Ground Water Near an Active Swine Facility?

    NASA Astrophysics Data System (ADS)

    Townsend, M. A.

    2001-05-01

    An active swine facility in south central Kansas appears to be cleaning up nitrate in regional ground water in an area with shallow ground water (<10 m), sandy soils, and irrigated and dry land row crop farming. This study used nitrogen stable isotopes and standard water chemistry to determine the impact of a bentonite lined hog lagoon on shallow ground-water chemistry. Regional ground water surrounding the facility had nitrate-nitrogen values routinely measured above 10 ppm. Chloride concentrations in the area ranged from 3 to 25 ppm and bicarbonate values ranged from 45 to 200 ppm. Two periods of sampling in the area showed nitrogen isotope values in the fertilizer range (<+2 to +8) and nitrate-N values above 10 ppm for all wells within a mile of a swine facility except for the monitoring well downgradient of the facility. This well had nitrate-N values of 4 to 5 ppm and nitrogen isotope values in the animal waste range (+13 to +20) which is similar to the value measured for the waste lagoon (+18). Chloride and bicarbonate values at all of the monitoring wells, except the well downgradient from the lagoon, were similar to the regional ground water. The lagoon water had >500 ppm chloride and >1400 ppm ammonium-N. The downgradient monitoring well had chloride values > 100 ppm and bicarbonate values above 400 ppm for the two sampling periods. Use of chloride ratios showed that approximately 30% of the water contributing to the downgradient well sample was from lagoon leakage. Preliminary calculations of the amount of bicarbonate resulting from denitrification processes, chloride ratios, and nitrogen isotope values suggest that the sampled water is a mixture of denitrified regional ground water plus lagoon water. Although the nitrate values near the swine facility appear to be decreasing, the long-term impact of increased salt load on the regional ground water is unknown at this time.

  14. UTILIZING INNOVATIVE TECHNOLOGIES FOR ENVIRONMENTAL CLEAN-UP, SAVAHHAH RIVER SITE

    SciTech Connect

    Bergren, C

    2009-01-07

    The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units and facilities that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990s), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required continued and significant funding while often failing to meet acceptable clean-up goals and objectives. Recognizing that a more cost-effective approach was needed, SRS implemented new and complementary remediation methods focused on active and passive technologies targeted to solve specific remediation problems. Today, SRS uses technologies such as chemical/pH-adjusting injection, phytoremediation, underground cutoff walls, dynamic underground stripping, soil fracturing, microbial degradation, baroballs, electrical resistance heating, soil vapor extraction, and microblowers to more effectively treat contamination at lower costs. Additionally, SRS's remediation approach cost effectively maximizes cleanup as SRS works proactively with multiple regulatory agencies. Using GIS, video, animation, and graphics, SRS is able to provide an accurate depiction of the evolution of SRS groundwater and vadose zone cleanup activities to convince stakeholders and regulators of the effectiveness of various cleanup

  15. Kinetics of combined SO/sub 2//NO in flue gas clean-up

    SciTech Connect

    Chang, S.G.; Littlejohn, D.

    1985-03-01

    The kinetics of reactions involving SO/sub 2/, NO, and ferrous chelate additives in wet flue gas simultaneous desulfurization and denitrification scrubbers are discussed. The relative importance of these reactions are assessed. The relevance of these reactions to spray dryer processes for combined SO/sub 2//NO flue gas clean-up is addressed. 37 refs., 7 figs.

  16. Hebei Spirit Oil Spill Exposure and Subjective Symptoms in Residents Participating in Clean-Up Activities

    PubMed Central

    Cheong, Hae-Kwan; Lee, Jong Seong; Kwon, Hojang; Ha, Eun-Hee; Hong, Yun-Chul; Choi, Yeyong; Jeong, Woo-Chul; Hur, Jongil; Lee, Seung-Min; Kim, Eun-Jung; Im, Hosub

    2011-01-01

    Objectives This study was conducted to examine the relationship between crude oil exposure and physical symptoms among residents participating in clean-up work associated with the Hebei Spirit oil spill, 2007 in Korea. Methods A total of 288 residents responded to a questionnaire regarding subjective physical symptoms, sociodemographic characteristics and clean-up activities that occurred between two and eight weeks after the accident. Additionally, the urine of 154 of the respondents was analyzed for metabolites of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) and heavy metals. To compare the urinary levels of exposure biomarkers, the urine of 39 inland residents who were not directly exposed to the oil spill were analyzed. Results Residents exposed to oil remnants through clean-up work showed associations between physical symptoms and the exposure levels defined in various ways, including days of work, degree of skin contamination, and levels of some urinary exposure biomarkers of VOCs, metabolites and metals, although no major abnormalities in urinary exposure biomarkers were observed. Conclusions This study provides evidence of a relationship between crude oil exposure and acute human health effects and suggests the need for follow-up to evaluate the exposure status and long-term health effects of clean-up participants. PMID:22125768

  17. Determination of fusaric acid in maize using molecularly imprinted SPE clean-up

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new liquid chromatography method to detect fusaric acid in maize is reported based on molecularly imprinted polymer solid phase extraction clean-up (MISPE) using mimic-templated molecularly-imprinted polymers. Picolinic acid was used as a toxin analog for imprinting polymers during a thermolytic s...

  18. Case Study: Using Microbe Molecular Biology for Gulf Oil Spill Clean Up

    ERIC Educational Resources Information Center

    Jones, Daniel R.

    2011-01-01

    This case has the student actively investigate the regulation of expression of a novel bacterial gene in the context of attempts to solve a real world problem, clean up of the April 2010 Deep Water Horizon oil spill in the Gulf of Mexico. Although the case is fictitious, it is based on factual gene regulatory characteristics of oil-degrading…

  19. TECHNICAL APPROACHES TO CHARACTERIZING AND CLEANING UP BROWNFIELDS SITES: GUIDANCE DOCUMENT

    EPA Science Inventory

    NRMRL-CIN-1741 SAIC. Technical Approaches to Characterizing and Cleaning up Brownfields Sites. EPA/625/R/00/009 (NTIS PB2002-105021) , Available: 68-C7-0011. The guidance document gives assistance to communities, decision-makers, states and municipalities, academia, and the p...

  20. Efficiency of different protocols for enamel clean-up after bracket debonding: an in vitro study

    PubMed Central

    Sigilião, Lara Carvalho Freitas; Marquezan, Mariana; Elias, Carlos Nelson; Ruellas, Antônio Carlos; Sant'Anna, Eduardo Franzotti

    2015-01-01

    Objective: This study aimed to assess the efficiency of six protocols for cleaning-up tooth enamel after bracket debonding. Methods: A total of 60 premolars were divided into six groups, according to the tools used for clean-up: 12-blade bur at low speed (G12L), 12-blade bur at high speed (G12H), 30-blade bur at low speed (G30L), DU10CO ORTHO polisher (GDU), Renew System (GR) and Diagloss polisher (GD). Mean roughness (Ra) and mean roughness depth (Rz) of enamel surface were analyzed with a profilometer. Paired t-test was used to assess Ra and Rz before and after enamel clean-up. ANOVA/Tukey tests were used for intergroup comparison. The duration of removal procedures was recorded. The association between time and variation in enamel roughness (∆Ra, ∆Rz) were evaluated by Pearson's correlation test. Enamel topography was assessed by scanning electron microscopy (SEM). Results: In Groups G12L and G12H, original enamel roughness did not change significantly. In Groups G30L, GDU, GR and GD, a smoother surface (p < 0.05) was found after clean-up. In Groups G30L and GD, the protocols used were more time-consuming than those used in the other groups. Negative and moderate correlation was observed between time and (∆Ra, ∆Rz); Ra and (∆Ra, ∆Rz); Rz (r = - 0.445, r = - 0.475, p < 0.01). Conclusion: All enamel clean-up protocols were efficient because they did not result in increased surface roughness. The longer the time spent performing the protocol, the lower the surface roughness. PMID:26560825

  1. A review of polymer nanofibres by electrospinning and their application in oil-water separation for cleaning up marine oil spills.

    PubMed

    Sarbatly, Rosalam; Krishnaiah, Duduku; Kamin, Zykamilia

    2016-05-15

    The growths of oil and gas exploration and production activities have increased environmental problems, such as oil spillage and the resulting pollution. The study of the methods for cleaning up oil spills is a critical issue to protect the environment. Various techniques are available to contain oil spills, but they are typically time consuming, energy inefficient and create secondary pollution. The use of a sorbent, such as a nanofibre sorbent, is a technique for controlling oil spills because of its good physical and oil sorption properties. This review discusses about the application of nanofibre sorbent for oil removal from water and its current developments. With their unique physical and mechanical properties coupled with their very high surface area and small pore sizes, nanofibre sorbents are alternative materials for cleaning up oil spills. PMID:27016959

  2. Oak Ridge Cleanup Vision: Moving to the Future by Cleaning Up the Past - 13291

    SciTech Connect

    Cange, Susan M.; Wieland, Christopher C.; DePaoli, Susan M.

    2013-07-01

    received buy-in from the leadership in Headquarters, the regulators, and the community. Issues EM was facing in 2009 are presented. Resulting lessons learned and subsequent changes that the Office has gone through in the past several years in order to improve performance in the safe execution of work, relationships with external stakeholders, and communications both internally and externally are discussed. Results of these efforts are provided as a summary of Program accomplishments, including a strong focus on the future. EM's motto, Moving to the Future by Cleaning up the Past, will be demonstrated through the Program's mission, which includes protecting the region's health and environment; ensuring the continuation of ongoing vital missions being conducted by DOE on the Oak Ridge Reservation; and making clean land available for future use at all three sites, with a near-term focus on Re-industrialization of ETTP. (authors)

  3. Improved clean-up for the determination of lasalocid in 'difficult' food matrices.

    PubMed

    Tarbin, J A; Rawlings, E; Tyler, D; Sharman, M

    2002-01-01

    Methodology has been developed for the determination of lasalocid in analytically 'difficult' matrices such as processed and spiced foods. The procedure was based on an existing silica-based solid-phase extraction (SPE) clean-up to which was added a novel NH2 SPE step before HPLC with fluorescence detection. Use of the additional step enabled the determination of lasalocid in matrices such as baby food, meat pies ('pasties'), etc. Analysis of these matrices was not possible using the standard clean-up on its own. Chromatography showed a massive reduction in the amount of co-extractives and interferences. Validation data were obtained down to the 10-40 mg kg(-1) level for a range of products. Recoveries ranged from 74% at 10 microg kg(-1) for pork sausages to 96% at 40 microg kg(-1) for meat pies. PMID:11817373

  4. Sectored Clean-up Work Plan for Housekeeping Category Waste Sites

    SciTech Connect

    S. J. Nacht

    2000-02-01

    The Sectored Clean-up Work Plan (SCWP) replaces the Housekeeping Category Corrective Action Unit Work Plan and provides a strategy to be used for conducting housekeeping activities using a sectored clean-up approach. This work plan provides a process by which one or more existing housekeeping category Corrective Action Sites (CASS) from the Federal Facility Agreement and Consent Order and/or non-FFACO designated waste site(s) are grouped into a sector for simultaneous remediation and cleanup. This increases effectiveness and efficiencies in labor, materials, equipment, cost, and time. This plan is an effort by the U.S. Department of Energy to expedite work in a more organized and efficient approach. The objectives of this plan are to: Group housekeeping FFACO CASS and non-FFACO housekeeping sites into sectors and remediate during the same field visit; Provide consistent documentation on FFACO CAS and non-FFACO clean-up activities; Perform similar activities under one approved document; Remediate areas inside the Deactivation and Decommissioning facilities and compounds in a campaign-style remediation; and Increase efficiencies and cost-effectiveness, accelerate cleanups, reduce mobilization, demobilization, and remediation costs.

  5. Immuno-ultrafiltration as a new strategy in sample clean-up of aflatoxins.

    PubMed

    Reiter, Elisabeth Viktoria; Cichna-Markl, Margit; Chung, Duck-Hwa; Zentek, Jürgen; Razzazi-Fazeli, Ebrahim

    2009-05-01

    The present paper describes the development of a new clean-up strategy for the analysis of aflatoxins (AFs) in food. The sample preparation method is based on immuno-ultrafiltration (IUF) which, in contrast to immunoaffinity chromatography, makes use of antibodies in free form. After selecting an appropriate ultrafiltration (UF) device and optimizing different operation conditions the IUF method was applied to the clean-up of maize and rice. Quantification of AFs was carried out by HPLC and fluorescence detection, after postcolumn derivatization in a Kobracell. The IUF method was shown to be as selective as sample clean-up using commercial immunoaffinity columns. Recovery rates and RSD for the AFs G(2), G(1), B(2) and B(1) in spiked rice were found to be 76 +/- 3, 76 +/- 2, 83 +/- 5 and 99 +/- 14%, respectively. The analysis of a FAPAS (food analysis performance assessment scheme) maize material resulted in AFs concentrations which were in the range assigned by the producer of the reference material. PMID:19472274

  6. The effect of water spray upon incineration flue gas clean-up

    NASA Astrophysics Data System (ADS)

    Wang, Haigang; Li, Bin; Liu, Shi; Pan, Zhonggang; Yan, Guizhang

    2000-06-01

    The existence of liquid water was found very important in incineration flue gas clean-up systems for enhancing the absorption of acid components contained. In a newly developed incineration flue gas clean-up tower, which works in a semi-dry mode, the water is injected in the form of spray to maximum its contact surface with the gas. The criteria for the design of the water nozzles would be high water concentration but no liquid impinging on the solid wall and complete evaporation inside the tower. In order to optimize the atomizer design, the effects of the spray type (hollow or solid cone), their initial droplet size distribution and water flow rate on the performance of the acid gas absorption were investigated. The liquid behaviour was studied with a fluid dynamic simulation code, and the overall performance was checked experimentally. This paper presents the use of a commercial CFD code, FLUENT, and some modifications made during such investigation. The modification includes the viscosity of the flue gas defined as a function of the temperature, and the initial mass fraction of different droplet size group described with an exponential distribution formula of Rosin-Rammler. The investigation results (the optimal spray parameters) were used to guide the water nozzle design. The general performance of the flue gas clean-up system measured during the plant operation complied with the design criteria.

  7. Coupling detergent lysis/clean-up methodology with intact protein fractionation for enhanced proteome characterization

    SciTech Connect

    Sharma, Ritin; Dill, Brian; Chourey, Karuna; Shah, Manesh B; Verberkmoes, Nathan C; Hettich, Robert {Bob} L

    2012-01-01

    The expanding use of surfactants for proteome sample preparations has prompted the need to systematically optimize the application and removal of these MS-deleterious agents prior to proteome measurements. Here we compare four different detergent clean-up methods (Trichloroacetic acid (TCA) precipitation, Chloroform/Methanol/Water (CMW) extraction, commercial detergent removal spin column method (DRS) and filter-aided sample preparation(FASP)) with respect to varying amounts of protein biomass in the samples, and provide efficiency benchmarks with respect to protein, peptide, and spectral identifications for each method. Our results show that for protein limited samples, FASP outperforms the other three clean-up methods, while at high protein amount all the methods are comparable. This information was used in a dual strategy of comparing molecular weight based fractionated and unfractionated lysates from three increasingly complex samples (Escherichia coli, a five microbial isolate mixture, and a natural microbial community groundwater sample), which were all lysed with SDS and cleaned up using FASP. The two approaches complemented each other by enhancing the number of protein identifications by 8%-25% across the three samples and provided broad pathway coverage.

  8. Clean-up of a pesticide-lanolin mixture by gel permeation chromatography.

    PubMed

    López-Mesas, M; Crespi, M; Brach, J; Mullender, J P

    2000-12-01

    In this study, the efficiency of a clean-up method by gel permeation chromatography (GPC) for the separation of pesticides from lanolin is analyzed. The pesticides analyzed belong to two different families, organophosphorous and synthetic pyrethroids. Lanolin, a standard mixture of the pesticides, and a lanolin-pesticides mixture are injected in a GPC column. The recoveries and elution times from the GPC column of lanolin (by a gravimetric method) and pesticides (by gas chromatography-electron capture detector) are determined. From this column, a good separation of the lanolin-pesticides mixture is observed. PMID:11144515

  9. Molecularly imprinted polymers for the clean-up of a basic drug from environmental and biological samples.

    PubMed

    Chapuis, Florence; Mullot, Jean-Ulrich; Pichon, Valérie; Tuffal, Gilles; Hennion, Marie-Claire

    2006-12-01

    A molecularly imprinted polymer (MIP) was synthesized and evaluated to selectively extract an alpha-blocker, i.e. alfuzosin, from human plasma. The synthesis of the MIP was performed in dichloromethane with methacrylic acid as monomer and the target drug as template. A first series of experiments was carried out in dichloromethane to estimate the potential of the MIP in its specific recognition medium, i.e. dichloromethane, by developing a selective procedure and by measuring the capacity of the sorbent. An optimized procedure was developed for the selective extraction of alfuzosin with a recovery close to 100% in this medium and a specific capacity of 1.3 micromol g(-1) of MIP was measured. A study in aqueous media was also carried out by a comprehensive approach of the retention mechanism in order to build a selective procedure of extraction. The effects of the amount and of the charge of cations were studied and an optimal pH value was defined to limit matrix effects. Then, the alfuzosin MIP was then directly used to selectively extract the target drug from human plasma with an extraction recovery of 60%. Lastly, a soil was extracted by a pressurized solvent and the resulting extract was cleaned up on the MIP, showing the possibility to use this selective sorbent for the sample treatment of various complex matrices. PMID:17055520

  10. Determination of amphetamines in hair by integrating sample disruption, clean-up and solid phase derivatization.

    PubMed

    Argente-García, A; Moliner-Martínez, Y; Campíns-Falcó, P; Verdú-Andrés, J; Herráez-Hernández, R

    2016-05-20

    The utility of matrix solid phase dispersion (MSPD) for the direct analysis of amphetamines in hair samples has been evaluated, using liquid chromatography (LC) with fluorescence detection and precolumn derivatization. The proposed approach is based on the employment of MSPD for matrix disruption and clean-up, followed by the derivatization of the analytes onto the dispersant-sample blend. The fluorogenic reagent 9-fluorenylmethyl chloroformate (FMOC) has been used for derivatization. Different conditions for MSPD, analyte purification and solid phase derivatization have been tested, using amphetamine (AMP), methamphetamine (MET), ephedrine (EPE) and 3,4-methylenedioxymethamphetamine (MDMA) as model compounds. The results have been compared with those achieved by using ultrasound-assisted alkaline digestion and by MSPD combined with conventional solution derivatization. On the basis of the results obtained, a methodology is proposed for the analysis of amphetamines in hair which integrates sample disruption, clean-up and derivatization using a C18 phase. Improved sensitivity is achieved with respect to that obtained by the alkaline digestion or by the MSPD followed by solution derivatization methods. The method can be used for the quantification of the tested amphetamines within the 2.0-20.0ng/mg concentration interval, with limits of detection (LODs) of 0.25-0.75ng/mg. The methodology is very simple and rapid (the preparation of the sample takes less than 15min). PMID:27108048

  11. Early aging in Chernobyl clean-up workers: long-term study.

    PubMed

    Krasnov, V; Kryukov, V; Samedova, E; Emelianova, I; Ryzhova, I

    2015-01-01

    This paper represents data of long-term open prospective study. 312 male clean-up workers, who participated in elimination of the Chernobyl disaster consequences in 1986-87, were observed and examined in Moscow Research Institute of Psychiatry. The average age of patients was 57,0 ± 6,8 years. All patients were diagnosed with psychoorganic syndrome, caused by combination of different factors, which led to early cerebrovascular pathology, which was confirmed by clinical, neuropsychological, and instrumental examination. Anamnesis and the level of social adaptation were also assayed. Clinical estimation was done with the use of specially developed Clinical Psychopathological Chart. All the symptoms were divided into 4 groups (asthenic, psychovegetative, dysthymic, and cognitive symptom-complexes). No pronounced signs of dementia were observed. The control group included 44 clean-up workers without mental disorders. Predomination of various exogenous factors before and after accident was noted. Therapy included different vasotropic remedies, as well as family therapy, art therapy, and cognitive training. The possibilities of the reverse development of symptoms were statistically proved. The results allow making a conclusion that these disorders could not be explained either by radiation effects or by PTSD but connected with cerebrovascular pathology. PMID:25692150

  12. Spinning filter separation system for oil spill clean-up operation

    SciTech Connect

    Wehrle, J.; Fischer, E.C.; Kenney, W.P.; Korczynski, J.F.; Gracik, T.D.

    1996-09-26

    According to current technology, effective clean up of oil spills from the surface of ocean water is performed by an oil sweeper vessel within which oil contaminated water is collected for transport to remotely located on-shore equipment within which oil separation and disposal is performed. The processing of large quantities of oil polluted ocean water is accordingly time consuming as well as costly. It is therefore an important object of the present invention to provide a less costly oil spill clean up system involving more rapid processing of large quantities of oil polluted ocean water. In accordance with the present invention, oil polluted ocean water is processed at an oil spill location by continuous separation during pressurized flow of the water through at least two separator devices within which successive reduction in oil concentration is effected with respect to a separated portion of the water by filtered flow through porous membrane walls to correspondingly increase the oil concentration within the other remaining portion of water being processed. The first portion of the processed water when sufficiently reduced in oil concentration is discharged for return to the oil spill location, while the remaining portion is collected until a sufficient level of oil concentration therein is achieved to permit disposal thereof by burning at the oil spill site.

  13. Early Aging in Chernobyl Clean-Up Workers: Long-Term Study

    PubMed Central

    Krasnov, V.; Kryukov, V.; Samedova, E.; Emelianova, I.; Ryzhova, I.

    2015-01-01

    This paper represents data of long-term open prospective study. 312 male clean-up workers, who participated in elimination of the Chernobyl disaster consequences in 1986-87, were observed and examined in Moscow Research Institute of Psychiatry. The average age of patients was 57,0 ± 6,8 years. All patients were diagnosed with psychoorganic syndrome, caused by combination of different factors, which led to early cerebrovascular pathology, which was confirmed by clinical, neuropsychological, and instrumental examination. Anamnesis and the level of social adaptation were also assayed. Clinical estimation was done with the use of specially developed Clinical Psychopathological Chart. All the symptoms were divided into 4 groups (asthenic, psychovegetative, dysthymic, and cognitive symptom-complexes). No pronounced signs of dementia were observed. The control group included 44 clean-up workers without mental disorders. Predomination of various exogenous factors before and after accident was noted. Therapy included different vasotropic remedies, as well as family therapy, art therapy, and cognitive training. The possibilities of the reverse development of symptoms were statistically proved. The results allow making a conclusion that these disorders could not be explained either by radiation effects or by PTSD but connected with cerebrovascular pathology. PMID:25692150

  14. Using integrated geospatial mapping and conceptual site models to guide risk-based environmental clean-up decisions.

    PubMed

    Mayer, Henry J; Greenberg, Michael R; Burger, Joanna; Gochfield, Michael; Powers, Charles; Kosson, David; Keren, Roger; Danis, Christine; Vyas, Vikram

    2005-04-01

    Government and private sector organizations are increasingly turning to the use of maps and other visual models to provide a depiction of environmental hazards and the potential risks they represent to humans and ecosystems. Frequently, the graphic presentation is tailored to address a specific contaminant, its location and possible exposure pathways, and potential receptors. Its format is usually driven by the data available, choice of graphics technology, and the audience being served. A format that is effective for displaying one contaminant at one scale at one site, however, may be ineffective in accurately portraying the circumstances surrounding a different contaminant at the same site, or the same contaminant at a different site, because of limitations in available data or the graphics technology being used. This is the daunting challenge facing the U.S. Department of Energy (DOE), which is responsible for the nation's legacy wastes from nuclear weapons research, testing, and production at over 100 sites in the United States. In this article, we discuss the development and use of integrated geospatial mapping and conceptual site models to identify hazards and evaluate alternative long-term environmental clean-up strategies at DOE sites located across the United States. While the DOE probably has the greatest need for such information, the Department of Defense and other public and private responsible parties for many large and controversial National Priority List or Superfund sites would benefit from a similar approach. PMID:15876215

  15. Estimation of the uncertainties of extraction and clean-up steps in pesticide residue analysis of plant commodities.

    PubMed

    Omeroglu, P Yolci; Ambrus, A; Boyacioglu, D

    2013-01-01

    Extraction and clean-up constitute important steps in pesticide residue analysis. For the correct interpretation of analytical results, uncertainties of extraction and clean-up steps should be taken into account when the combined uncertainty of the analytical result is estimated. In the scope of this study, uncertainties of extraction and clean-up steps were investigated by spiking (14)C-labelled chlorpyrifos to analytical portions of tomato, orange, apple, green bean, cucumber, jackfruit, papaya and starfruit. After each step, replicate measurements were carried out with a liquid scintillation counter. Uncertainties in extraction and clean-up steps were estimated separately for every matrix and method combination by using within-laboratory reproducibility standard deviation and were characterised with the CV of recoveries. It was observed that the uncertainty of the ethyl acetate extraction step varied between 0.8% and 5.9%. The relative standard uncertainty of the clean-up step with dispersive SPE used in the method known as QuEChERS was estimated to be around 1.5% for tomato, apple and green beans. The highest variation of 4.8% was observed in cucumber. The uncertainty of the clean-up step with gel permeation chromatography ranged between 5.3% and 13.1%, and it was relatively higher than that obtained with the dispersive SPE method. PMID:23216411

  16. Overview of extraction, clean-up and detection techniques for the determination of organic pollutants in sewage sludge: a review.

    PubMed

    Zuloaga, O; Navarro, P; Bizkarguenaga, E; Iparraguirre, A; Vallejo, A; Olivares, M; Prieto, A

    2012-07-29

    analytical procedure (extraction, clean-up and analysis) have been reviewed. PMID:22769001

  17. Studies of leukemia and thyroid disease among Chernobyl clean-up workers from the Baltics

    SciTech Connect

    Inskip, P.D.; Tekkel, M.; Rahu, M.

    1997-03-01

    Following the reactor accident at Chernobyl in late April of 1986, hundreds of thousands of men from throughout the former Soviet Union were sent to Chernobyl to entomb the damaged reactor, remove radioactive debris, and help decontaminate the local environment. They remained for an average of three months and were allowed to accumulate up to 25 cGy of radiation before being sent home. Doses for some workers may have exceeded the allowable limit. The experience of Chernobyl clean-up workers is potentially informative about cancer risk associated with protracted exposure to low levels of radiation. Cohorts of clean-up workers from the Baltic Republics were assembled for study, based on military records and other lists. The study population includes 4,833 men from Estonia 5,709 from Latvia and at least 5,446 from Lithuania, where a pilot study is underway. They are being monitored for cancer incidence through linkages with the corresponding national cancer registries. Biodosimetric assays, including fluorescent in situ hybridization (FISH) for chromosome translocation analysis and the glycophorin A (GPA) somatic cell mutation assay, are being used to supplement information about radiation doses from worker records and questionnaires. Thyroid screening examinations, including palpation, ultrasound and, selectively, fine-needle aspiration biopsies were performed on nearly 2,000 workers in the Estonian cohort (mean age, 40 y) during the spring of 1995, nine years after the reactor accident. The study is still in progress. Work began first in Estonia, and results presented here pertain to this subgroup except as otherwise noted. The average age at the time of arrival at Chernobyl was 31 years. 62% were sent in 1986. Possible reasons for the apparent absence or rarity of radiation-induced thyroid nodules include low and protracted doses, low susceptibility among men exposed as adults, and insufficient passage of time since the accident.

  18. [Determination of indicator polychlorinated biphenyls in vegetable oils by double clean-up-gas chromatography].

    PubMed

    Ding, Liping; Cai, Chunping; Wang, Danhong

    2014-11-01

    To investigate the residues of seven indicator polychlorinated biphenyls (PCBs) in vegetable oils, a method was established for the determination of trace PCBs in vegetable oils by double clean-up coupled with gas chromatography (GC). After extracted with acetonitrile, the sample extract was concentrated to dryness followed by re-dissolving with hexane. And the solution was pretreated by adding concentrated sulfuric acid followed cleaned-up with silica gel in dispersive solid-phase extraction protocol, then analyzed by GC with external standard meth- od. Under the optimized chromatographic conditions, the analysis was carried out with a capillary column (HP-5, 30 m x 0.32 mm x 0.25 μm) at a flow rate of 0.8 mL/min, and the sample volume was 1.00 μL. Monitoring with an electron-capture detector, all the target analytes were separated by temperature-programming of the column. Good linearities were obtained in the range of 10-500 μg/L for the seven indicator PCBs with the correlation coefficients greater than 0. 999. For different matrices, the limits of detection (S/N = 3) and limits of quantitation (S/N = 10) were in the range of 1.8-8.9 pg/kg and 5.9-29.8 μg/kg, respectively. At three spiked levels of 10, 20 and 100 μg/kg of the seven indicator PCBs in olive oil, palm oil and peanut oil blank samples, the average recoveries ranged from 71.0% to 105.5% with the RSDs of 4.0%-11.3%. The method is simple, rapid and accurate, and can be used for the routine analysis of the indicator PCBs in vegetable oils. PMID:25764663

  19. The integration of science and politics to clean up 50 years in the nuclear sandbox

    SciTech Connect

    Lyons, C.E.; Holeman, T.

    1999-07-01

    The Cold War was fought between world superpowers for approximately 40 years from the end of the second World War until the end of the 1980s. During that time, the US government devoted billions of dollars to the development and production of nuclear weapons. Now the Cold War is over and the US is left with numerous nuclear weapons factories, stockpiles of nuclear materials, and mountains of waste to decontaminate and decommission. In the heat of the Cold War, little or no thought was given to how the facilities building bombs would be dismantled. Far too little attention was paid to the potential human health and environmental impact of the weapons production. Now, dozens of communities across the country face the problems this negligence created. In many cases, the location, extent, and characteristics of the waste and contamination are unknown, due to negligence or due to intentional hiding of waste and associated problems. Water supplies are contaminated and threatened; air quality is degraded and threatened; workers and residents risk contamination and health impacts; entire communities risk disaster from potential nuclear catastrophe. The US government, in the form of the US Department of Energy (DOE), now accepts responsibility for creating and cleaning up the mess. But it is the local communities, the home towns of the bomb factories and laboratories, that carry a significant share of the burden of inventing the science and politics required to clean up 50 years in the nuclear sandbox. The purpose of this paper is to evaluate the role of the local community in addressing the cleanup of the US nuclear weapons complex. Local governments do not own nor are responsible for the environmental aftermath, but remain the perpetual neighbor to the facility, the hometown of workers, and long-term caretaker of the off-site impacts of the on-site contamination and health risks.

  20. Enamel Surface Roughness after Debonding of Orthodontic Brackets and Various Clean-Up Techniques

    PubMed Central

    Ahrari, Farzaneh; Akbari, Majid; Akbari, Javad; Dabiri, Ghahraman

    2013-01-01

    Objective: This study aimed to evaluate enamel roughness after adhesive removal using different burs and an Er:YAG laser. Materials and Methods: The buccal surfaces of forty human premolars were sealed by two layers of nail varnish, except for a circular area of 3 mm in diameter on the middle third. The enamel surfaces were initially subjected to profilometry analysis and four parameters of surface irregularity (Ra, Rq, Rt and Rz) were recorded. Following bracket bonding and debonding, adhesive remnants were removed by tungsten carbide burs in low- or high- speed handpieces (group 1 and 2, respectively), an ultrafine diamond bur (group 3) or an Er:YAG laser (250 mJ, long pulse, 4 Hz) (group 4), and surface roughness parameters were measured again. Then, the buccal surfaces were polished and the third profilometry measurements were performed. Results: The specimens that were cleaned with a low speed tungsten carbide bur showed no significant difference in surface irregularity between the different treatment stages (p>0.05). Surface roughness increased significantly after clean-up with the diamond bur and the Er:YAG laser (p<0.01). In comparison between groups, adhesive removal with tungsten carbide burs at slow- or high-speed handpieces produced the lowest, while enamel clean-up with the Er:YAG laser caused the highest values of roughness measurements (P<0.05). Conclusion: Under the study conditions, application of the ultrafine diamond bur or the Er:YAG laser caused irreversible enamel damage on tooth surface, and thus these methods could not be recommended for removing adhesive remnants after debonding of orthodontic brackets. PMID:23724206

  1. SOIL ECOTOXICITY ASSAYS

    EPA Science Inventory

    Traditionally, remedial technologies developed to reduce the risk associated with contaminated soils have been evaluated using specific chemical concentrations as clean up goals. A more complete understanding of remedial treatments can be obtained by evaluating soil ecotoxicity ...

  2. Comparison of Clean-Up Methods for Ochratoxin A on Wine, Beer, Roasted Coffee and Chili Commercialized in Italy

    PubMed Central

    Prelle, Ambra; Spadaro, Davide; Denca, Aleksandra; Garibaldi, Angelo; Gullino, Maria Lodovica

    2013-01-01

    The most common technique used to detect ochratoxin A (OTA) in food matrices is based on extraction, clean-up, and chromatography detection. Different clean-up cartridges, such as immunoaffinity columns (IAC), molecular imprinting polymers (MIP), Mycosep™ 229, Mycospin™, and Oasis® HLB (Hydrophilic Lipophilic balance) as solid phase extraction were tested to optimize the purification for red wine, beer, roasted coffee and chili. Recovery, reproducibility, reproducibility, limit of detection (LOD) and limit of quantification (LOQ) were calculated for each clean-up method. IAC demonstrated to be suitable for OTA analysis in wine and beer with recovery rate >90%, as well as Mycosep™ for wine and chili. On the contrary, MIP columns were the most appropriate to clean up coffee. A total of 120 samples (30 wines, 30 beers, 30 roasted coffee, 30 chili) marketed in Italy were analyzed, by applying the developed clean-up methods. Twenty-seven out of 120 samples analyzed (22.7%: two wines, five beers, eight coffees, and 12 chili) resulted positive to OTA. A higher incidence of OTA was found in chili (40.0%) more than wine (6.6%), beers (16.6%) and coffee (26.6%). Moreover, OTA concentration in chili was the highest detected, reaching 47.8 µg/kg. Furthermore, three samples (2.5%), two wines and one chili, exceeded the European threshold. PMID:24152987

  3. Comparison of clean-up methods for ochratoxin A on wine, beer, roasted coffee and chili commercialized in Italy.

    PubMed

    Prelle, Ambra; Spadaro, Davide; Denca, Aleksandra; Garibaldi, Angelo; Gullino, Maria Lodovica

    2013-10-01

    The most common technique used to detect ochratoxin A (OTA) in food matrices is based on extraction, clean-up, and chromatography detection. Different clean-up cartridges, such as immunoaffinity columns (IAC), molecular imprinting polymers (MIP), Mycosep™ 229, Mycospin™, and Oasis® HLB (Hydrophilic Lipophilic balance) as solid phase extraction were tested to optimize the purification for red wine, beer, roasted coffee and chili. Recovery, reproducibility, reproducibility, limit of detection (LOD) and limit of quantification (LOQ) were calculated for each clean-up method. IAC demonstrated to be suitable for OTA analysis in wine and beer with recovery rate >90%, as well as Mycosep™ for wine and chili. On the contrary, MIP columns were the most appropriate to clean up coffee. A total of 120 samples (30 wines, 30 beers, 30 roasted coffee, 30 chili) marketed in Italy were analyzed, by applying the developed clean-up methods. Twenty-seven out of 120 samples analyzed (22.7%: two wines, five beers, eight coffees, and 12 chili) resulted positive to OTA. A higher incidence of OTA was found in chili (40.0%) more than wine (6.6%), beers (16.6%) and coffee (26.6%). Moreover, OTA concentration in chili was the highest detected, reaching 47.8 µg/kg. Furthermore, three samples (2.5%), two wines and one chili, exceeded the European threshold. PMID:24152987

  4. Evaluation of Methyl Bromide Alternatives Efficacy against Soil-Borne Pathogens, Nematodes and Soil Microbial Community

    PubMed Central

    Xie, Hongwei; Yan, Dongdong; Mao, Liangang; Wang, Qiuxia; Li, Yuan; Ouyang, Canbin; Guo, Meixia; Cao, Aocheng

    2015-01-01

    Methyl bromide (MB) and other alternatives were evaluated for suppression of Fusarium spp., Phytophthora spp., and Meloidogyne spp. and their influence on soil microbial communities. Both Fusarium spp. and Phytophthora spp. were significantly reduced by the MB (30.74 mg kg-1), methyl iodide (MI: 45.58 mg kg-1), metham sodium (MS: 53.92 mg kg-1) treatments. MS exhibited comparable effectiveness to MB in controlling Meloidogyne spp. and total nematodes, followed by MI at the tested rate. By contrast, sulfuryl fluoride (SF: 33.04 mg kg-1) and chloroform (CF: 23.68 mg kg-1) showed low efficacy in controlling Fusarium spp., Phytophthora spp., and Meloidogyne spp. MB, MI and MS significantly lowered the abundance of different microbial populations and microbial biomass in soil, whereas SF and CF had limited influence on them compared with the control. Diversity indices in Biolog studies decreased in response to fumigation, but no significant difference was found among treatments in PLFA studies. Principal component and cluster analyses of Biolog and PLFA data sets revealed that MB and MI treatments greatly influenced the soil microbial community functional and structural diversity compared with SF treatment. These results suggest that fumigants with high effectiveness in suppressing soil-borne disease could significantly influence soil microbial community. PMID:25723395

  5. Determination of diphenamide, napropamide and metolachlor in tobacco by gel permeation chromatographic clean-up and high performance liquid chromatography.

    PubMed

    Liu, Hongxia; Dang, Yuanlin; Zhang, Shusheng; Liu, Huimin; Qu, Lingbo; Liao, Xincheng; Zhao, Yufen; Wu, Yangjie

    2005-05-01

    Diphenamide, napropamide and metolachlor (FIG. 1) are selective, pre-emergence arylamide herbicides used to control the growth of annual grasses and broadleaf weeds in a variety of fields, e.g. fruit trees, nuts, corns, green crops, etc. They possess high activity and moderate toxicity. For food and environment safety, the detailed investigations on their residues and metabolism are very important. Diphenamide, napropamide and metolachlor in the pesticide products, serum, urine, soil, environmental water, fruits and wine have been widely analyzed by ELISA, fluorescence, phosphorescence, capillary electrophoresis, high performance liquid chromatography (HPLC), gas chromatography(GC) and GC mass spectrometry (GC-MS). However, to our knowledge, simultaneous residue analysis of diphenamide, napropamide and metolachlor in tobacco samples has not been extensively documented. Tobacco is greatly consumed by smokers throughout the world. The pesticide residue in tobaccos might be potentially harmful to smokers' health. With this in mind the residue determination and control of diphenamide, napropamide and metolachlor in the tobacco leaves are very important for tobacco products and consumers. For these three herbicides, the tolerable maximum residue limits (MRLs) have been limited ranging from 0.05 (for tobacco products) to 5 mg/kg (for tobacco leaves) in different European countries. For the complex tobacco samples, the GC and HPLC with UV detection suffer from matrix interference making quantification and identification of these herbicides difficult. In such cases the removal of the matrix effects and identification of the target compounds are of great importance. The present work reports the extraction and clean up procedures, as well as, the chromatographic conditions developed for the simultaneous determination of diphenamide, napropamide and metolachlor residues in the fluecured tobacco leaves, from the different sources using HPLC-UV method. PMID:16477944

  6. Terminating Safeguards on Excess Special Nuclear Material: Defense TRU Waste Clean-up and Nonproliferation - 12426

    SciTech Connect

    Hayes, Timothy; Nelson, Roger

    2012-07-01

    The Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) manages defense nuclear material that has been determined to be excess to programmatic needs and declared waste. When these wastes contain plutonium, they almost always meet the definition of defense transuranic (TRU) waste and are thus eligible for disposal at the Waste Isolation Pilot Plant (WIPP). The DOE operates the WIPP in a manner that physical protections for attractiveness level D or higher special nuclear material (SNM) are not the normal operating condition. Therefore, there is currently a requirement to terminate safeguards before disposal of these wastes at the WIPP. Presented are the processes used to terminate safeguards, lessons learned during the termination process, and how these approaches might be useful for future defense TRU waste needing safeguards termination prior to shipment and disposal at the WIPP. Also described is a new criticality control container, which will increase the amount of fissile material that can be loaded per container, and how it will save significant taxpayer dollars. Retrieval, compliant packaging and shipment of retrievably stored legacy TRU waste has dominated disposal operations at WIPP since it began operations 12 years ago. But because most of this legacy waste has successfully been emplaced in WIPP, the TRU waste clean-up focus is turning to newly-generated TRU materials. A major component will be transuranic SNM, currently managed in safeguards-protected vaults around the weapons complex. As DOE and NNSA continue to consolidate and shrink the weapons complex footprint, it is expected that significant quantities of transuranic SNM will be declared surplus to the nation's needs. Safeguards termination of SNM varies due to the wide range of attractiveness level of the potential material that may be directly discarded as waste. To enhance the efficiency of shipping waste with high TRU fissile content to WIPP, DOE designed an over

  7. [Non-Parametric Analysis of Radiation Risks of Mortality among Chernobyl Clean-Up Workers].

    PubMed

    Gorsky, A I; Maksioutov, M A; Tumanov, K A; Shchukina, N V; Chekin, S Yu; Ivanov, V K

    2016-01-01

    Analysis of the relationship between dose and mortality from cancer and circulation diseases in the cohort of Chernobyl clean-up workers based on the data from the National Radiation and Epidemiological Registry was performed. Medical and dosimetry information on the clean-up workers, males, who got radiation doses from April 26, 1986 to April 26, 1987, which was accumulated from 1992 to 2012, was used for the analysis. The total size of the cohort was 42929 people, 12731 deaths were registered in the cohort, among them 1893 deaths from solid cancers and 5230 deaths were from circulation diseases. An average age of the workers was 39 years in 1992 and the mean dose was 164 mGy. The dose-effect relationship was estimated with the use of non-parametric analysis of survival with regard to concurrence of risks of mortality. The risks were estimated in 6 dose groups of similar size (1-70, 70-130, 130-190, 190-210, 210-230 and.230-1000 mGy). The group "1-70 mGy" was used as control. Estimated dose-effect relationship related to cancers and circulation diseases is described approximately with a linear model, coefficient of determination (the proportion of variability explained by the linear model) for cancers was 23-25% and for circulation diseases - 2-13%. The slope coefficient of the dose-effect relationship normalized to 1 Gy for the ratio of risks for cancers in the linear model was 0.47 (95% CI: -0.77, 1.71), and for circulation diseases it was 0.22 (95% CI: -0.58, 1.02). Risks coefficient (slope coefficient of excess mortality at a dose of 1 Gy) for solid cancers was 1.94 (95% CI: - 3.10, 7.00) x 10(-2) and for circulation diseases it was 0.67 (95% CI: -9.61, 11.00) x 10(-2). 137 deaths from radiation-induced cancers and 47 deaths from circulation diseases were registered during a follow up period. PMID:27534064

  8. Determination of organochlorine and pyrethroid pesticides in fruit and vegetables using solid phase extraction clean-up cartridges.

    PubMed

    Sharif, Zawiyah; Man, Yaakob Bin Che; Hamid, Nazimah Sheikh Abdul; Keat, Chin Cheow

    2006-09-15

    A method to determine six organochlorine and three pyrethroid pesticides in grape, orange, tomato, carrot and green mustard based on solvent extraction followed by solid phase extraction (SPE) clean-up is described. The pesticides were spiked into the sample prior to analysis, extracted with ethyl acetate, evaporated and reconstituted with a solvent mixture of acetone:n-hexane (3:7). Three different sorbents (Strong Anion Exchanger/Primary Secondary Amine (SAX/PSA), Florisil and C18) were used for the clean-up step. Pesticides were eluted with 5mL of acetone:n-hexane (3:7, v/v) and determined by gas chromatography and electron-capture detection (GC-ECD). SAX/PSA was the sorbent, which provided chromatograms with less interference and the mean recoveries obtained were within 70-120% except for captafol. The captafol recoveries for grape were within acceptable range with C18 clean-up column. PMID:16857206

  9. Multiresidue determination of pesticides in plants by high-performance liquid chromatography following gel permeation chromatographic clean-up.

    PubMed

    Balinova, A

    1998-10-01

    Gel permeation chromatography was applied as a clean-up step in a HPLC multiresidue method for the determination of several pesticides in plants, not amenable to analysis by GC. The pesticides investigated were diflubenzuron, triflumuron, clofentezine, hexythiazox and flufenoxuron. The clean-up technique resulted in a good separation of analytes from co-extractive matrix compounds. Complete HPLC separation of all pesticides was achieved under the conditions selected. The analytical procedure was characterized with high accuracy and precision and acceptable sensitivity to meet requirements for monitoring these pesticides in crops. PMID:9818389

  10. Hanford tank clean up: A guide to understanding the technical issues

    SciTech Connect

    Gephart, R.E.; Lundgren, R.E.

    1995-12-31

    One of the most difficult technical challenges in cleaning up the US Department of Energy`s (DOE) Hanford Site in southeast Washington State will be to process the radioactive and chemically complex waste found in the Site`s 177 underground storage tanks. Solid, liquid, and sludge-like wastes are contained in 149 single- and 28 double-shelled steel tanks. These wastes contain about one half of the curies of radioactivity and mass of hazardous chemicals found on the Hanford Site. Therefore, Hanford cleanup means tank cleanup. Safely removing the waste from the tanks, separating radioactive elements from inert chemicals, and creating a final waste form for disposal will require the use of our nation`s best available technology coupled with scientific advances, and an extraordinary commitment by all involved. The purpose of this guide is to inform the reader about critical issues facing tank cleanup. It is written as an information resource for the general reader as well as the technically trained person wanting to gain a basic understanding about the waste in Hanford`s tanks -- how the waste was created, what is in the waste, how it is stored, and what are the key technical issues facing tank cleanup. Access to information is key to better understanding the issues and more knowledgeably participating in cleanup decisions. This guide provides such information without promoting a given cleanup approach or technology use.

  11. Diving behaviour of wildlife impacted by an oil spill: A clean-up and rehabilitation success?

    PubMed

    Chilvers, B L; Morgan, K M; Finlayson, G; Sievwright, K A

    2015-11-15

    The value of rehabilitating oiled wildlife is an on-going global debate. On October 5, 2011, the cargo vessel C/V Rena grounded on Astrolabe Reef, New Zealand (NZ), spilling over 300 tonnes of heavy fuel oil. As part of the Rena oil spill response, 383 little blue penguins (LBP, Eudyptula minor) were captured, cleaned, rehabilitated and released back into a cleaned environment. This research investigates foraging behaviour changes due either to the oil spill or by the rehabilitation process by comparing the diving behaviour of rehabilitated (n=8) and non-rehabilitated (n=6) LBPs and with LBP populations throughout NZ. Stabile isotope analysis of feathers was also used to investigate diet. There were no foraging behaviour differences between rehabilitated and non-rehabilitated LBPs and the overall diving behaviour of these LBPs have similar, if not less energetic, foraging behaviour than other LBPs in NZ. This suggests the rehabilitation process and clean-up undertaken after the Rena appears effective and helps justify the rehabilitation of oiled wildlife across the world. PMID:26424224

  12. Diethylaminoethyl-cellulose clean-up of a large volume naphthenic acid extract.

    PubMed

    Frank, Richard A; Kavanagh, Richard; Burnison, B Kent; Headley, John V; Peru, Kerry M; Der Kraak, Glen Van; Solomon, Keith R

    2006-08-01

    The Athabasca oil sands of Alberta, Canada contain an estimated 174 billion barrels of bitumen. During oil sands refining processes, an extraction tailings mixture is produced that has been reported as toxic to aquatic organisms and is therefore collected in settling ponds on site. Investigation into the toxicity of these tailings pond waters has identified naphthenic acids (NAs) and their sodium salts as the major toxic components, and a multi-year study has been initiated to identify the principal toxic components within NA mixtures. Future toxicity studies require a large volume of a NA mixture, however, a well-defined bulk extraction technique is not available. This study investigated the use of a weak anion exchanger, diethylaminoethyl-cellulose (DEAE-cellulose), to remove humic-like material present after collecting the organic acid fraction of oil sands tailings pond water. The NA extraction and clean-up procedure proved to be a fast and efficient method to process large volumes of tailings pond water, providing an extraction efficiency of 41.2%. The resulting concentrated NA solution had a composition that differed somewhat from oil sands fresh tailings, with a reduction in the abundance of lower molecular weight NAs being the most significant difference. This reduction was mainly due to the initial acidification of tailings pond water. The DEAE-cellulose treatment had only a minor effect on the NA concentration, no noticeable effect on the NA fingerprint, and no significant effect on the mixture toxicity towards Vibrio fischeri. PMID:16469358

  13. 77 FR 35431 - Final Alternative Soils Standards for the Uravan, CO, Uranium Mill

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-13

    ... standards for a 30-day comment period (76 FR 70170; November 10, 2011). The public comment period and... COMMISSION Final Alternative Soils Standards for the Uravan, CO, Uranium Mill AGENCY: Nuclear Regulatory... of Colorado's proposed alternative soils standards will achieve a level of stabilization...

  14. FINAL REPORT. GENETIC ANALYSIS OF STRESS RESPONSES IN SOIL BACTERIA FOR ENHANCED BIOREMEDIATION OF MIXED CONTAMINANTS

    EPA Science Inventory

    Bioremediation is the technological process whereby biological systems are harnessed toeffect the clean-up of environmental pollutants. Bioremediation has been demonstrated to be anappropriate alternative to conventional clean-up strategies in many cases. For example, aerobicb...

  15. Alternative sorbents for the dispersive solid-phase extraction step in quick, easy, cheap, effective, rugged and safe method for extraction of pesticides from rice paddy soils with determination by liquid chromatography tandem mass spectrometry.

    PubMed

    Arias, Jean Lucas de Oliveira; Rombaldi, Caroline; Caldas, Sergiane Souza; Primel, Ednei Gilberto

    2014-09-19

    The clean-up step is essential to reduce interferences, improve quantification and help to maintain the integrity of the chromatographic system when working with complex matrices. In this study, alternative materials were evaluated as sorbents in the dispersive solid-phase extraction (D-SPE) for the determination and extraction of seventeen pesticides from rice paddy soil samples by the quick, easy, cheap, effective, rugged and safe (QuEChERS) method coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Chitin, chitosan, diatomaceous earth and PSA were compared in terms of extraction efficiency and matrix effect. The best results were achieved when chitosan was used. Quantification limits ranged from 0.1 to 100μgkg(-1). Calibration curves showed correlation coefficient values higher than 0.98. Results of accuracy and precision in the spiked soil samples between 60% and 120%, with a relative standard deviation lower than 20%, were reached for 15 out of 17 pesticides. The matrix effect was evaluated and only one compound was influenced by the matrix components, showing medium effect. Results showed that alternative materials are more effective and less expensive than traditional sorbents which have been usually employed, i.e., they may be used in the D-SPE step during the extraction of pesticides from rice paddy soils. PMID:25115454

  16. Extraction and clean-up of contaminants and toxicants from food for mass spectrometric analysis--a literature review.

    PubMed

    Reid, W J

    1986-01-01

    This report presents a review of the literature on the extraction and clean-up procedures used prior to the analysis, by mass spectrometry, of organic contaminants and toxicants in foods and food-related materials. It includes a brief description of the uses of a mass spectrometer and shows how the mode of operation of the machine can influence the amount of clean-up necessary before a sample is presented for analysis. The review covers a variety of contaminants of different compound types in a wide range of foods and not only discusses sample preparation techniques that have been used for contaminant analysis by mass spectrometry but also considers some that could be used. The most commonly used techniques involve solvent extraction followed by a clean-up using liquid-liquid partition or column chromatography or both, although a number of newer methods being evolved are moving towards the ideal of a single-step extraction and clean-up process. PMID:3514283

  17. Clinical aspects of the health disturbances in Chernobyl Nuclear Power Plant accident clean-up workers (liquidators) from Latvia.

    PubMed

    Eglite, M E; Zvagule, T J; Rainsford, K D; Reste, J D; Curbakova, E V; Kurjane, N N

    2009-06-01

    The health status of some 6,000 workers from Latvia who went to clean-up the Chernobyl Nuclear Power Plant (CNPP) site following the explosion on 26 April 1986 has been analyzed. The data on these workers have been recorded in the Latvian State Register of Occupational disease patients and people exposed to ionizing radiation due to Chernobyl NPP accident (Latvian State Register) that was established in 1994. From these data, estimates have been made of external ionizing radiation to which these workers were exposed together with observations on the impact of exposure to heavy metals (especially lead and zinc) and radioactive isotopes released during the reactor 'meltdown'. These factors along with psycho-emotional and social-economic stresses account for a marked excess of mortality and morbidity in the group of CNPP accident clean-up workers compared with that of the non-exposed normal Latvian population adjusted for age and sex. The number of diseases or conditions in the CNPP accident clean-up workers has progressively risen from an average of 1.3 in 1986 to 10.9 in 2007. This exceeds for the Latvian population when adjusted for age and sex. The most serious conditions affect the nervous, digestive, respiratory, cardiovascular, endocrine (especially thyroid) and immunological systems. While the morbidity associated with diseases of the respiratory and digestive systems has decreased in recent years that in the other systems is increasing. In recent years, there has been an increased occurrence of cancers affecting the thyroid, prostate and stomach. Clinical and laboratory investigations suggest that surviving CNPP accident clean-up workers exhibit signs of immuno-inflammatory reactions causing premature aging with evidence of autoimmune diseases and immunological deficiencies or abnormalities. It is suggested that the CNPP accident clean-up workers may have a specific syndrome, the 'Chernobyl post-radiation neurosomatic polypathy', due to sustained oxidant

  18. Policies to clean up toxic industrial contaminated sites of Gela and Priolo: a cost-benefit analysis

    PubMed Central

    2011-01-01

    Background Cost-benefit analysis is a transparent tool to inform policy makers about the potential effect of regulatory interventions, nevertheless its use to evaluate clean-up interventions in polluted industrial sites is limited. The two industrial areas of Gela and Priolo in Italy were declared "at high risk of environmental crisis" in 1990. Since then little has been done to clean the polluted sites and reduce the health outcomes attributable to pollution exposure. This study, aims to quantify the monetary benefits resulting from clean-up interventions in the contaminated sites of Gela and Priolo. Methods A damage function approach was used to estimate the number of health outcomes attributable to industrial pollution exposure. Extensive one way analyses and probabilistic analyses were conducted to investigate the sensitivity of results to different model assumptions. Results It has been estimated that, on average, 47 cases of premature death, 281 cases of cancer and 2,702 cases of non-cancer hospital admission could be avoided each year by removing environmental exposure in these two areas. Assuming a 20 year cessation lag and a 4% discount rate we calculate that the potential monetary benefit of removing industrial pollution is €3,592 million in Priolo and €6,639 million in Gela. Conclusions Given the annual number of health outcomes attributable to pollution exposure the effective clean-up of Gela and Priolo should be prioritised. This study suggests that clean-up policies costing up to €6,639 million in Gela and €3,592 million in Priolo would be cost beneficial. These two amounts are notably higher than the funds allocated thus far to clean up the two sites, €127.4 million in Gela and €774.5 million in Priolo, implying that further economic investments - even considerable ones - could still prove cost beneficial. PMID:21797993

  19. Establishing a universal swabbing and clean-up protocol for the combined recovery of organic and inorganic explosive residues.

    PubMed

    Song-im, Nopporn; Benson, Sarah; Lennard, Chris

    2012-11-30

    A single-step solvent extraction and a solid-phase extraction (SPE) clean-up procedure was developed and optimised in order to establish a universal sampling and clean-up protocol for the combined recovery of organic and inorganic explosive residues. Mixtures of three common swabbing solvents (acetone, acetonitrile and methanol) with water, in various ratios, were assessed for the extraction of four target organic explosives [pentaerythritol tetranitrate (PETN), 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and triacetone triperoxide (TATP)] and two inorganic anions (chlorate and nitrate) from alcohol wipes that were used as a swabbing medium. An efficient, single-step extraction of both organic and inorganic compounds from the wipes was achieved using 60% v/v methanol/water. To develop a clean-up procedure, four commercially available SPE cartridges (Oasis HLB, Isolute(®) C18, Bond-Elut(®) ENV and ABS ELUT Nexus) and an in-house packed XAD-7 cartridge were firstly evaluated for their retention capacity toward three organic explosives (PETN, TNT and RDX) in a mixture of methanol and water. A SPE technique was then developed and optimised from the short-listed sorbents with four representative organic explosives (including TATP). The Nexus cartridge was found to provide a suitable sorbent for extract clean-up following swab extraction with 60% v/v methanol/water. By incorporating the optimised clean-up procedure with the application of a polyester-based alcohol wipe as a sampling medium, a universal swabbing protocol for the combined recovery of both organic and inorganic explosive residues was established. The feasibility of the proposed protocol was assessed by collection and quantitation of the residue from a mixture of TNT, PETN and chlorate deposited on a laminate test surface. PMID:22959657

  20. Alternate data sources for soil surveys on rangeland

    USGS Publications Warehouse

    Horvath, Emil H.; Klingebiel, A.A.; Moore, D.G.; Fosnight, E.A.

    1983-01-01

    the feasibility of using this approach for producing physiographic maps as an aid for mapping soils and range sites. The project is a cooperative investigation of the Earth Resources Observation Systems Data Center of the U.S. Geological Survey, the Soil Conservation Service, and the Bureau of Land Management.

  1. Alternating Paratill Shank Placement for Enhanced Soil Disruption

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A ParatillTM is a type of bent-leg non-inversion tillage implement commonly used on Coastal Plain soils of the southeastern U.S. to break naturally occurring consolidated soil layers. Conservation tillage operations with a ParatillTM are usually conducted with the shanks placed in the same location...

  2. Using soil function evaluation in multi-criteria decision analysis for sustainability appraisal of remediation alternatives.

    PubMed

    Volchko, Yevheniya; Norrman, Jenny; Rosén, Lars; Bergknut, Magnus; Josefsson, Sarah; Söderqvist, Tore; Norberg, Tommy; Wiberg, Karin; Tysklind, Mats

    2014-07-01

    Soil contamination is one of the major threats constraining proper functioning of the soil and thus provision of ecosystem services. Remedial actions typically only address the chemical soil quality by reducing total contaminant concentrations to acceptable levels guided by land use. However, emerging regulatory requirements on soil protection demand a holistic view on soil assessment in remediation projects thus accounting for a variety of soil functions. Such a view would require not only that the contamination concentrations are assessed and attended to, but also that other aspects are taking into account, thus addressing also physical and biological as well as other chemical soil quality indicators (SQIs). This study outlines how soil function assessment can be a part of a holistic sustainability appraisal of remediation alternatives using multi-criteria decision analysis (MCDA). The paper presents a method for practitioners for evaluating the effects of remediation alternatives on selected ecological soil functions using a suggested minimum data set (MDS) containing physical, biological and chemical SQIs. The measured SQIs are transformed into sub-scores by the use of scoring curves, which allows interpretation and the integration of soil quality data into the MCDA framework. The method is demonstrated at a study site (Marieberg, Sweden) and the results give an example of how soil analyses using the suggested MDS can be used for soil function assessment and subsequent input to the MCDA framework. PMID:24529453

  3. Variable-Sweep Transition Flight Experiment (VSTFE): Stability code development and clean-up glove data analysis

    NASA Technical Reports Server (NTRS)

    Rozendaal, Roger A.

    1987-01-01

    The primary objective of the Variable Sweep Transition Flight Experiment (VSTFE) was to establish an improved swept wing transition criterion. The development of the Unified Stability System gave a way of quickly examining disturbance growth for a wide variety of laminar boundary layers. The disturbance growth traces shown are too scattered to define a transition criteria to replace the F-111 data band, which has been used successfully to design NLF gloves. Still, a careful review of the clean-up glove data may yield cases for which the transition location is known more accurately. Liquid crystal photographs of the clean-up glove show much spanwise variation in the transition front for some conditions, and this further complicates the analyses. Several high quality cases are needed in which the transition front is well defined and at a relatively constant chordwise station.

  4. Effects of demolition and beach clean-up operations on birds on a coastal mudflat in New Jersey

    NASA Astrophysics Data System (ADS)

    Burger, Joanna

    1988-07-01

    Coastal lands are increasingly exposed to disturbances from demolition, beach clean-up, and construction for development. Although data exist concerning the effects of investigators on breeding populations, little information is available for migrant populations. I investigated the effects of demolition and beach clean-up on resident and migrant birds on a coastal mudflat in New Jersey. A year's censusing before work initiation was used to determine when demolition and clean-up would affect the least number of birds. Work activity on and along the beach was from 15 October to 15 November 1985. The overall population size was lower in 1985 compared to the same period in 1984, although the drop in numbers was not due solely to human disturbance. Human work activity influenced avian distribution along the mudflat: birds moved farther along the beach and out onto the mudflat when activity began, and moved back onto the mudflat when activity ceased. For gulls, foraging efficiency was lowered when work began and did not return to previous levels until 60-90 min after work began. Gulls that moved farther out on the mudflat had significantly lower foraging efficiencies than did those that remained close to the beach. Efforts to mitigate the adverse effects on birds by restricting human activity to a 100 m stretch of beach at any one time succeeded in significantly reducing adverse effects and in allowing birds some space to rest and feed.

  5. Novel fracture technology proves marginal Viking prospect economic, part II: Well clean-up, flowback and testing

    SciTech Connect

    Haidar, S.; Rylance, M.; Tybero, G.

    1996-12-31

    Having completed both fracture treatments as discussed in a companion paper, this paper continues on to describe the post fracture shut-in, clean-up and well testing operations that took place on the Viking Wx exploration well 49/17-12. These operations involved the removal of Resin Coated Proppant (RCP) from the wellbore, via Coiled Tubing (CT), through the use of a specially designed jetting nozzle. The RCP pack stability at a concentration of 3.0 lb/ft{sup 2} (as per planned design) had already been tested in a flowback cell. The use of a Surface Read-Out (SRO) gauge, combined with gas, water and proppant flow rates as well as the viscosity of fracturing fluids returns, enabled real time calculation of the drag forces, on the proppant pack, during clean-up. The flow rate, in the field, was controlled such that the calculated drag forces remained below those observed in the laboratory. Following the clean-up a flow and build-up test was conducted, to evaluate the fracture half length and fracture conductivity, from which a Pseudo-radial skin was calculated. The Non-Darcy effects in the fracture were also evaluated, and finally the short term and long term well deliverabilities were assessed.

  6. Analysis of fusaric acid in maize using molecularly imprinted solid phase extraction (MISPE) clean-up and ion-pair LC with diode array UV detection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusaric acid is a phytotoxin and mycotoxin occasionally found in maize contaminated with Fusarium fungi. A selective sample clean-up procedure was developed to detect fusaric acid in maize using molecularly imprinted solid phase extraction (MISPE) clean-up coupled with ion-pair liquid chromatography...

  7. Historical Waste Retrieval and Clean-up Operations at Nuclear facility no.56, at the Cadarache Nuclear Research Centre

    SciTech Connect

    Santucci, C.

    2008-01-15

    Among the different activities of the CEA research centre in Cadarache, located in the south of France, one of the most important involves cleaning, cleansing dismantling, decommissioning, and recovery of legacy wastes. This presentation will give an overview of the waste retrieval project from the historical interim storage facility called INB 56. The project is divided into three different sub-projects: the historical unpacked waste retrieval, the historical canister retrieval and the draining and clean-up of the spent fuel pools. All the described operations are conducted in accordance with the ALARA principle and the optimization of the waste categorization. The overall project, including the complete clean-up of the facility and its de-licensing, is due to end by 2020. The aim of this document is to outline the general ongoing historical waste retrieval operations and future projects on the INB 56 at the Cadarache research centre. In the final analysis, it can be seen that most of the waste is to be sent to the new CEDRA facility. Nevertheless one major goal of this project is to optimize the waste categorization and therefore to send the canisters to the ANDRA LLW site whenever possible. Two means will allow us to reach this goal: - The sorting out of un-packed waste in order to constitute a LLW canister - A wide range of measurements (gamma spectrometry, neutron measurement, tomography) in order to assess the exact nature of the contents in the historical canisters. Taking waste treatment and conditioning into account well in advance is a factor of prime importance that must be managed early in the elaboration of the decommissioning scenario. Precise knowledge of the physical and radiological inventories is of the utmost importance in defining the best waste pathway. Overall operations on the facility are due to end by 2020 including complete clean-up of the facility and its de-licensing.

  8. Extraction agents for the removal of polycyclic aromatic hydrocarbons (PAHs) from soil in soil washing technologies.

    PubMed

    Lau, Ee Von; Gan, Suyin; Ng, Hoon Kiat; Poh, Phaik Eong

    2014-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in soil have been recognised as a serious health and environmental issue due to their carcinogenic, mutagenic and teratogenic properties. One of the commonly employed soil remediation techniques to clean up such contamination is soil washing or solvent extraction. The main factor which governs the efficiency of this process is the solubility of PAHs in the extraction agent. Past field-scale soil washing treatments for PAH-contaminated soil have mainly employed organic solvents or water which is either toxic and costly or inefficient in removing higher molecular weight PAHs. Thus, the present article aims to provide a review and discussion of the alternative extraction agents that have been studied, including surfactants, biosurfactants, microemulsions, natural surfactants, cyclodextrins, vegetable oil and solution with solid phase particles. These extraction agents have been found to remove PAHs from soil at percentages ranging from 47 to 100% for various PAHs. PMID:24100092

  9. Absorbent pads for Containment, Neutralization, and Clean-Up of Environmental Spills Containing Chemically-Reactive Agents

    NASA Technical Reports Server (NTRS)

    Davis, Dennis D. (Inventor)

    1997-01-01

    A pad for cleaning up liquid spills is described which contains a porous surface covering, and an absorbent interior containing chemically reactive reagents for neutralizing noxious chemicals within the spilled liquid. The porous surface and the absorbent component would normally consist of chemically resistant materials allowing tentative spill to pass. The absorbent interior which contains the neutralizing reagents can but is not required to be chemically resilient and conducts the liquid chemical spill towards the absorbent interior containing the chemically reactive reagents where the dangerous and undesirable chemicals within the chemical spill are then neutralized as well as removed from the premises.

  10. Absorbent Pads for Containment, neutralization, and clean-up of environmental spills containing chemically-reactive agents

    NASA Technical Reports Server (NTRS)

    Davis, Dennis D. (Inventor)

    1996-01-01

    A pad for cleaning up liquid spills is described which contains a porous surface covering, and an absorbent interior containing chemically reactive reagents for neutralizing noxious chemicals within the spilled liquid. The porous surface and the absorbent component would normally consist of chemically resistant materials allowing tentative spill to pass. The absorbent interior which contains the neutralizing reagents can but is not required to be chemically resilient and conducts the liquid chemically reactive reagents where the dangerous and undesirable chemicals within the chemical spill are then neutralized as well as removed from the premises.

  11. A Team of Seven--The Tanks Focus Area program providing technical solutions for cleaning up DOE's radioactive waste tanks

    SciTech Connect

    Cosby, Wayne C.

    2000-09-04

    The U.S. Department of Energy initiated the Tanks Focus Area (TFA) concept in 1994 to integrate the cleanup efforts of the sites containing radioactive tank wastes. A team of seven contractors and national laboratories was assembled to develop and implement technical solutions to the unique problems encountered in cleaning up large quantities of highly radioactive wastes in tanks that can only be accessed through riser pipes. TFA work focuses on safety, characterization, retrieval, pretreatment, immobilization, and closure. Many technologies are under development, two of which are the highly successful cesium removal system and the robotic light duty utility arm for deploying equipment inside tanks.

  12. Method of and apparatus for preheating pressurized fluidized bed combustor and clean-up subsystem of a gas turbine power plant

    DOEpatents

    Cole, Rossa W.; Zoll, August H.

    1982-01-01

    In a gas turbine power plant having a pressurized fluidized bed combustor, gas turbine-air compressor subsystem and a gas clean-up subsystem interconnected for fluid flow therethrough, a pipe communicating the outlet of the compressor of the gas turbine-air compressor subsystem with the interior of the pressurized fluidized bed combustor and the gas clean-up subsystem to provide for flow of compressed air, heated by the heat of compression, therethrough. The pressurized fluidized bed combustor and gas clean-up subsystem are vented to atmosphere so that the heated compressed air flows therethrough and loses heat to the interior of those components before passing to the atmosphere.

  13. Anaerobic Soil Disinfestation (ASD) Combined with Soil Solarization as a Methyl Bromide Alternative: Vegetable Crop Performance and Soil Nutrient Dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil treatment by anaerobic soil disinfestation (ASD) combined with soil solarization can effectively control soilborne plant pathogens and plant-parasitic nematodes in specialty crop production systems. At the same time, research is limited on the impact of soil treatment by ASD + solarization on c...

  14. Reaching Part Per Trillion Clean-Up Criteria for Mercury in Water

    SciTech Connect

    Klasson, K. T.; Kosny, K.; Drescher, S. R.; Southworth, G. R.; Hensley, J. F.

    2003-02-24

    In the last couple of years, emphasis on environmental mercury contamination and elimination of mercury use has increased. The U.S. Department of Energy has for many decades maintained a stockpile of elemental mercury for operations and, as a consequence of its routine use, spills have occurred. These historical spills have resulted in some contamination of water streams and soils. In this work we examine a newly developed technique for removal of mercury from contaminated groundwater. In this application the mercury concentration was approximately 2.3 parts per billion and the treatment criterion was 200 parts per trillion. Several forms of mercury species contributed to the contamination. The treatment technique developed for this water was to convert all forms of mercury, through a series of fast chemical reactions, to elemental mercury, which was air-stripped from the water. This paper presents preliminary laboratory work on the method.

  15. A systematic assessment of the state of hazardous waste clean-up technologies. Quarterly technical progress report, April 1--June 30, 1993

    SciTech Connect

    Berg, M.T.; Reed, B.E.; Gabr, M.

    1993-07-01

    West Virginia University (WVU) and the US DOE Morgantown Energy Technology Center (METC) entered into a Cooperative Agreement on August 29, 1992 entitled ``Decontamination Systems Information and Research Programs.`` Stipulated within the Agreement is the requirement that WVU submit to METC a series of Technical Progress Report for Year 1 of the Agreement. This report reflects the progress and/or efforts performed on the following nine technical projects encompassed by the Year 1 Agreement for the period of April 1 through June 30, 1993: Systematic assessment of the state of hazardous waste clean-up technologies; site remediation technologies -- drain-enhanced soil flushing (DESF) for organic contaminants removal; site remediation technologies -- in situ bioremediation of organic contaminants; excavation systems for hazardous waste sites; chemical destruction of polychlorinated biphenyls; development of organic sensors -- monolayer and multilayer self-assembled films for chemical sensors; Winfield lock and dam remediation; Assessments of Technologies for hazardous waste site remediation -- non-treatment technologies and pilot scale test facility implementation; and remediation of hazardous sites with stream reforming.

  16. Determination of etoxazole residues in fruits and vegetables by SPE clean-up and HPLC-DAD.

    PubMed

    Malhat, Farag; Badawy, Hany; Barakat, Dalia; Saber, Ayman

    2013-01-01

    A method for determination of etoxazole residues in apples, strawberries and green beans was developed and validated. The analyte was extracted with acetonitrile from foodstuff and a charcoal-celite cartridge was used for clean-up of raw extracts. Reversed phase high performance liquid chromatography with photodiode array detector (HPLC-DAD) was used for the determination and quantification of etoxazole residues in the studied samples. The calibration graphs of etoxazole in a solvent or three blank matrixes were linear within the tested intervals 0.01-2 mg L(-1), with correlation coefficient of determination >0.999. The combined solid phase extraction (SPE) clean-up and the chromatographic method steps were sensitive and reliable for simultaneous determination of etoxazole residues in the studied samples. The average recoveries of etoxazole in the tested foodstuffs were between 93.4 to 102% at spiking levels of 0.01, 0.10, and 0.50 mg kg(-1), with relative standard deviations ranging from 2.8 to 4.7%, in agreement with directives for method validation in residue analyses. The limit of detection (LOD) of the HPLC-DAD system was 100 pg. The limit of quantification of the entire method was 0.01 mg kg(-1). PMID:23431971

  17. Application of single immunoaffinity clean-up for simultaneous determination of regulated mycotoxins in cereals and nuts.

    PubMed

    Vaclavikova, Marta; MacMahon, Shaun; Zhang, Kai; Begley, Timothy H

    2013-12-15

    A rapid and sensitive analytical strategy for the simultaneous determination of twelve mycotoxins (aflatoxins, fumonisins, zearalenon, deoxynivalenol, ochratoxin A, T-2 and HT-2 toxins) using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed and validated. The method was validated for peanuts, barley and maize-breakfast cereals; selected as they represent the matrices most often contaminated by mycotoxins. The method is designed for fast and reliable analyses of mycotoxins in regulatory, industrial and private laboratories. Multi-target immunoaffinity columns containing antibodies for all mycotoxins studied herein were used for sample clean-up. Method optimization was predominantly focused on the simplification of extraction and clean-up procedure recommended by column producers. This newly developed and simplified procedure decreased both the sample preparation time and the solvent volumes used for their processing. The analysis of all regulated mycotoxins was conducted by a newly developed UHPLC-MS/MS method with a sample run time of only ten minutes. The method trueness was tested with analytical spikes and certified reference materials, with recoveries ranging from 71% to 112% for all of the examined mycotoxins. PMID:24209351

  18. [The retrospective cytogenetic dosimetry using the results of conventional chromosomal analysis in Chernobyl clean-up workers].

    PubMed

    Maznik, N A; Vinnikov, V A

    2005-01-01

    The paper presents the results of the cohortal biodosimetry carried out in 435 Chernobyl clean-up workers, who were surveyed with the conventional cytogenetic technique in terms from several days to 10 years after the end of their duties in the Chernobyl accident exclusive zone. An empirical model of the aberrant cell dynamics was utilized for the calculation of mean initial yields of dicentrics and centric rings in groups with different terms and duration of staying in the Chernobyl zone. Corresponding protracted irradiation doses estimated from aberration levels ranged from 79 to 670 mGy. The probabilistic distribution of the radiation doses was constructed by the applying the Bayesian analysis to initial individual chromosome exchange yields extrapolated to the exposure termination moment. This distribution was characterized by the mean dose about 460 mGy and maximum of probability density in the interval of 50-300 mGy. For the late somatic risk assessment in clean-up workers the probabilistic distribution of equivalentally-acute radiation doses was proposed; that had the mean value about 270 mGy, modal classes of 250-350 mGy and 99.8% of the probability density concentrated within the dose range from 0 to 1000 mGy. PMID:16454338

  19. Analysis of polycyclic aromatic hydrocarbons in vegetable oils combining gel permeation chromatography with solid-phase extraction clean-up.

    PubMed

    Fromberg, A; Højgård, A; Duedahl-Olesen, L

    2007-07-01

    A semi-automatic method for the determination of polycyclic aromatic hydrocarbons (PAHs) in edible oils using a combined gel permeation chromatography/solid-phase extraction (GPC/SPE) clean-up is presented. The method takes advantage of automatic injections using a Gilson ASPEC XL sample handling system equipped with a GPC column (S-X3) and pre-packed silica SPE columns for the subsequent clean-up and finally gas chromatography-mass spectrometry (GC-MS) determination. The method was validated for the determination of PAHs in vegetable oils and it can meet the criteria for the official control of benzo[a]pyrene levels in foods laid down by the Commission of the European Communities. A survey of 69 vegetable oils sampled from the Danish market included olive oil as well as other vegetable oils such as rapeseed oil, sunflower oil, grape seed oil and sesame oil. Levels of benzo[a]pyrene in all the oils were low (<0.2-0.8 microg kg(-1)), except for one sample of sunflower oil containing 11 microg kg(-1) benzo[a]pyrene. PMID:17613061

  20. An assessment of alternative agricultural management practice impacts on soil carbon in the corn belt

    SciTech Connect

    Barnwell, T.O. Jr.; Jackson, R.B.; Mulkey, L.A.

    1993-12-31

    This impact of alternative management practices on agricultural soil C is estimated by a soil C mass balance modeling study that incorporates policy considerations in the analysis. A literature review of soil C modeling and impacts of management practices has been completed. The models selected for use and/or modification to meet the needs of representing soil C cycles in agroecosystems and impacts of management practices are CENTURY and DNDC. These models share a common ability to examine the impacts of alternative management practices on soil organic C, and are readily accessible. An important aspect of this effort is the development of the modeling framework and methodology that define the agricultural production systems and scenarios (i.e., crop-soil-climate combinations) to be assessed in terms of national policy, the integration of the model needs with available databases, and the operational mechanics of evaluating C sequestration potential with the integrated model/database system. We are working closely with EPA`s Office of Policy and Program Evaluation to define a reasonable set of policy alternatives for this assessment focusing on policy that might be affected through a revised Farm Bill, such as incentives to selectively promote conservation tillage, crop rotations, and/or good stewardship of the conservation reserve. Policy alternatives are translated into basic data for use in soil C models through economic models. These data, including such elements as agricultural practices, fertilization rates, and production levels are used in the soil C models to produce net carbon changes on a per unit area basis. The unit-area emissions are combined with areal-extent data in a GIS to produce an estimate of total carbon and nitrogen changes and thus estimate greenhouse benefits.

  1. Clean-up progress at the SNL/NM Classified Waste Landfill

    SciTech Connect

    Slavin, P.J.; Galloway, R.B.

    1999-11-30

    The Sandia National Laboratories/New Mexico (SNL/NM)Environmental Restoration Project is currently excavating the Classified Waste Landfill in Technical Area II, a disposal area for weapon components for approximately 40 years until it closed in 1987. Many different types of classified parts were disposed in unlined trenches and pits throughout the course of the landfill's history. A percentage of the parts contain explosives and/or radioactive components or contamination. The excavation has progressed backward chronologically from the last trenches filled through to the earlier pits. Excavation commenced in March 1998, and approximately 75 percent of the site (as defined by geophysical anomalies) has been completed as of November 1999. The material excavated consists primarily of classified weapon assemblies and related components, so disposition must include demilitarization and sanitization. This has resulted in substantial waste minimization and cost avoidance for the project as upwards of 90 percent of the classified materials are being demilitarized and recycled. The project is using field screening and lab analysis in conjunction with preliminary and in-process risk assessments to characterize soil and make waste determinations in a timely a fashion as possible. Challenges in waste management have prompted the adoption of innovative solutions. The hand-picked crew (both management and field staff) and the ability to quickly adapt to changing conditions has ensured the success of the project. The current schedule is to complete excavation in July 2000, with follow-on verification sampling, demilitarization, and waste management activities following.

  2. Water compatible stir-bar devices imprinted with underivatised glyphosate for selective sample clean-up.

    PubMed

    Gomez-Caballero, Alberto; Diaz-Diaz, Goretti; Bengoetxea, Olatz; Quintela, Amaia; Unceta, Nora; Goicolea, M Aranzazu; Barrio, Ramón J

    2016-06-17

    This paper reports the development of stir bars with a new MIP based coating, for the selective sorptive extraction of the herbicide glyphosate (GLYP). Molecular imprinting of the polymer has directly been carried out employing underivatised GLYP as the template molecule. Due to the poor solubility of the target compound in organic solvents, the MIP methodology has been optimised for rebinding in aqueous media, being the synthesis and the rebinding steps carried out in water:methanol mixtures and pure aqueous media. The coating has been developed by radical polymerisation initiated by UV energy, using N-allylthiourea and 2-dimethyl aminoethyl methacrylate as functional monomers and ethylene glycol dimethacrylate as the cross-linker. Mechanical stability of the coating has been improved using 1,3-divinyltetramethyldisiloxane in the polymerisation mixture. Under the optimised conditions, the MIP has demonstrated excellent selectivity for the target compound in the presence of structural analogues, including its major metabolites. The applicability of the proposed method to real matrices has also been assessed using river water and soil samples. Registered mean recoveries ranged from 90.6 to 97.3% and RSD values were below 5% in all cases, what confirmed the suitability of the described methodology for the selective extraction and quantification of GLYP. PMID:27207580

  3. Experimental evidence for drought induced alternative stable states of soil moisture.

    PubMed

    Robinson, David A; Jones, Scott B; Lebron, Inma; Reinsch, Sabine; Domínguez, María T; Smith, Andrew R; Jones, Davey L; Marshall, Miles R; Emmett, Bridget A

    2016-01-01

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction. PMID:26804897

  4. Experimental evidence for drought induced alternative stable states of soil moisture

    NASA Astrophysics Data System (ADS)

    Robinson, David. A.; Jones, Scott B.; Lebron, Inma; Reinsch, Sabine; Domínguez, María T.; Smith, Andrew R.; Jones, Davey L.; Marshall, Miles R.; Emmett, Bridget A.

    2016-01-01

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction.

  5. Controlled Soil Warming Powered by Alternative Energy for Remote Field Sites

    PubMed Central

    Johnstone, Jill F.; Henkelman, Jonathan; Allen, Kirsten; Helgason, Warren; Bedard-Haughn, Angela

    2013-01-01

    Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2°C in 1 m2 plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes. PMID:24386125

  6. Experimental evidence for drought induced alternative stable states of soil moisture

    PubMed Central

    Robinson, David. A.; Jones, Scott B.; Lebron, Inma; Reinsch, Sabine; Domínguez, María T.; Smith, Andrew R.; Jones, Davey L.; Marshall, Miles R.; Emmett, Bridget A.

    2016-01-01

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction. PMID:26804897

  7. Evaluation of anaerobic soil disinfestation as an alternative to methyl bromide fumigation in a Florida bell pepper-eggplant double crop system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anaerobic soil disinfestation (ASD) integrates principles of flooding with soil solarization, allowing reducing conditions to develop in concert with increased soil temperatures. This technology has recently been investigated as an alternative to chemical soil fumigation for control of soilborne pa...

  8. Biosurfactant-enhanced soil bioremediation

    SciTech Connect

    Kosaric, N.; Lu, G.; Velikonja, J.

    1995-12-01

    Bioremediation of soil contaminated with organic chemicals is a viable alternative method for clean-up and remedy of hazardous waste sites. The final objective in this approach is to convert the parent toxicant into a readily biodegradable product which is harmless to human health and/or the environment. Biodegradation of hydrocarbons in soil can also efficiently be enhanced by addition or in-situ production of biosufactants. It was generally observed that the degradation time was shortened and particularly the adaptation time for the microbes. More data from our laboratories showed that chlorinated aromatic compounds, such as 2,4-dichlorophenol, a herbicide Metolachlor, as well as naphthalene are degraded faster and more completely when selected biosurfactants are added to the soil. More recent data demonstrated an enhanced biodegradation of heavy hydrocarbons in petrochemical sludges, and in contaminated oil when biosurfactants were present or were added prior to the biodegradation process.

  9. Planar solid phase extraction clean-up for pesticide residue analysis in tea by liquid chromatography-mass spectrometry.

    PubMed

    Oellig, Claudia; Schwack, Wolfgang

    2012-10-19

    Efficient clean-up is indispensable for preventing matrix effects in multi-residue analysis of pesticides in food by liquid and gas chromatography (LC and GC) coupled to mass spectrometry (MS). High-throughput planar solid phase extraction (HTpSPE) was recently introduced as a new clean-up concept in residue analysis of pesticides in fruit and vegetables (C. Oellig, W. Schwack, 2011 [45]). Thin-layer chromatography (TLC) was used to completely separate pesticides from matrix compounds and to focus them into a sharp zone, followed by extraction of the target zone by the TLC-MS interface. As rather challenging matrices, tea samples were chosen in this study. Besides chlorophylls and polyphenols, high amount of caffeine is co-extracted resulting in strong matrix effects both in LC-MS and GC-MS. The former HTpSPE procedure was adapted to initial extracts of green and black tea resulting in colorless extracts nearly free of matrix effects and interferences, as shown for seven chemically representative pesticides (acetamiprid, penconazole, azoxystrobin, chlorpyrifos, pirimicarb, fenarimol, and mepanipyrim). LC-MS/MS calibration curves obtained in the range of 0.002-0.5 mg/kg from matrix-matched standards and solvent standards were nearly identical and demonstrated the effectiveness of clean-up by HTpSPE. Mean recoveries determined by LC-MS/MS against solvent standards at spiking levels of 0.01 and 0.1 mg/kg ranged between 72 and 114% with relative standard deviations (RSDs) of 0.7-4.7% (n=4), while LC-MS measurements of tea samples spiked at 1 mg/kg provided recoveries of 81-104% with RSDs of 1.2-4.9% (n=6). Using LC-MS/MS, the method showed high sensitivity with signal-to-noise ratios>10 for concentrations below 0.002 mg/kg. HTpSPE of one sample was done in a few minutes, while numerous samples were cleaned in parallel at minimal costs with very low sample and solvent consumption. PMID:22981507

  10. Evaluation of soil amendments as a remediation alternative for cadmium-contaminated soils under cacao plantations.

    PubMed

    Chavez, E; He, Z L; Stoffella, P J; Mylavarapu, R; Li, Y; Baligar, V C

    2016-09-01

    Elevated plant-available cadmium (Cd) in soils results in contamination to cacao (Theobroma cacao L) beans. Effectiveness of vermicompost and zeolite in reducing available Cd in three cacao-growing soils was studied under laboratory conditions. Sorption-desorption experiments were conducted in soils and amendments. Cadmium was added at 0 or 5 mg kg(-1) (spiked), then, amendments were incorporated at 0, 0.5, or 2 %. Amended soils were incubated at room temperature for 28 days. Plant-available Cd was determined using 0.01 M CaCl2 (WSE) and Mehlich 3 (M3) extraction procedures in subsamples taken from individual bags at six time intervals. Soils and amendments displayed different sorption characteristics and a better fit was attained with Freundlich model (R (2) > 0.82). Amendments were ineffective in reducing extractable Cd in non-spiked soils. In Cd-spiked soils, vermicompost at 2 % significantly reduced WSE-Cd (P < 0.01) from 3.36, 0.54, and 0.38 mg kg(-1) to values lower that instrument's detection in all the three soils and significantly diminished M3-extractable Cd (P < 0.05) from 4.62 to 4.11 mg kg(-1) in only one soil. Vermicompost at 0.5 % significantly decreased WSE-Cd (P < 0.01) from 3.04 and 0.31 to 1.69 and 0.20 mg kg(-1), respectively, in two soils with low sorption capacity for Cd. In contrast, zeolite failed to reduce WSE- or M3-extractable Cd in all studied soils. A negative correlation occurred between soil pH and WSE-Cd (r > -0.89, P < 0.01). The decrease in WSE-Cd appears to be associated with the increase in pH of the vermicompost-amended soils. PMID:27234831

  11. Climatic implications of alternating clay and carbonate formation in semiarid soils of South-Central Montana

    USGS Publications Warehouse

    Reheis, M.C.

    1987-01-01

    Evidence for climatic change is found in petrographic thin sections from soils formed on glaciofluvial deposits of Rock Creek and the lower Clarks Fork, Montana. These soils, presently in a semiarid climate, range from late Pliocene to Holocene in age, and have undergone periodic fluctuations in soil moisture caused by climatic changes. In the lower parts of soil B horizons, accretion of illuvial layers of clay (argillans) occurs mainly during wet (glacial) climatic periods, whereas carbonate precipitates mainly during dry (interglacial) climatic periods. Thin-section studies of the argillan and carbonate layers show that: (1) post-Pinedale soils that have formed only in the present interglacial climate contain areas of secondary carbonate unrelated to argillans, (2) soils formed on outwash of successively older glaciations contain proportionately more alternating layers of argillans and carbonate, and (3) the maximum number and sequence of layers in a soil correspond to the number of local cycles of glacial-outwash deposition and subsequent stream incision that followed the beginning of soil formation. These cycles are inferred to correspond to local glacial-interglacial fluctuations. The correspondence between the microscopic record and the glacial-outwash record for Rock Creek suggests that some of the climatic changes seen in the marine oxygen-isotope record did not strongly affect the study area. ?? 1987.

  12. Survey of aflatoxins in rice from Iran using immunoaffinity column clean-up and HPLC with fluorescence detection.

    PubMed

    Feizy, J; Beheshti, H R; Fahim, N Khoshbakht; Janati, S S Fakoor; Davari, G

    2010-01-01

    A study was undertaken to determine levels of aflatoxins in rice. A total of 261 rice samples were analyzed by HPLC using a method was based on the extraction of 50 g of finely ground rice plus 5 g NaCl with 200 ml of 80% methanol. After filtration and immunoaffinity clean-up, 20 µl was injected onto the HPLC. HPLC analysis was carried out using a Genesis RP C18 column (250 × 4.6, 4 µm I.D.) and a mobile phase with a linear gradient of water/methanol/acetonitrile (6 : 2 : 2 v/v) over 16 min. Aflatoxins were determined after post-column derivatisation with iodine by fluorescence detection at excitation and emission wavelengths of 365 and 445 nm, respectively. It was found that 68.9% of the rice samples contained aflatoxin B1 at levels greater than 0.2 ng g(-1). PMID:24779626

  13. Cleaning up of a nuclear facility: Destocking of Pu radioactive waste and nuclear Non-Destructive Assays

    NASA Astrophysics Data System (ADS)

    Jallu, F.; Allinei, P.-G.; Bernard, Ph.; Loridon, J.; Pouyat, D.; Torreblanca, L.

    2012-07-01

    In view to clean up a nuclear facility located at the CEA, Cadarache, France, three Non Destructive Assay (NDA) methods have been combined to characterize 2714 old, 100 L radioactive waste drums produced between 1980 and 1997. The results of X-ray radiography, passive neutron measurement and gamma-ray spectrometry are used together to extract both the βγ and α activities, and the Pu mass contained in each drum. Those drums will then be re-conditioned and cemented in 870 L containers, in order to be sent to the adequate disposal or interim storage. This paper presents the principle of the three NDA methods, the dedicated measurement setups, and it gives details about the setups, which have been especially designed and developed for that application. Uncertainties are dealt with in the last part of the paper.

  14. Effective clean-up and ultra high-performance liquid chromatography-tandem mass spectrometry for isoflavone determination in legumes.

    PubMed

    Vila-Donat, Pilar; Caprioli, Giovanni; Maggi, Filippo; Ricciutelli, Massimo; Torregiani, Elisabetta; Vittori, Sauro; Sagratini, Gianni

    2015-05-01

    Legumes are an excellent source of macronutrients and phytochemicals as isoflavones. The aim of this work was to develop a new analytical method for determining five isoflavone compounds, three of which are aglycons, namely daidzein, genistein, biochanin A, and two of which, daidzin and genistin, are glycosilated, in lentils and other pulses, using an effective clean-up system and UHPLC-MS/MS (triple quadrupole) method. The recoveries obtained by spiking the lentil samples with a standard mixture of isoflavones at three levels of fortification (5, 25 and 100 μg kg(-1)) were in the range of 54.4-111.1%, 68.6-91.1%, and 84.4-114%, respectively. The method was applied to analyse 48 lentil samples from central Italy and pulses for determining the isoflavone content, which was found to range from 1.1 to 95.6 μg kg(-1). PMID:25529710

  15. A new multiple-stage electrocoagulation process on anaerobic digestion effluent to simultaneously reclaim water and clean up biogas.

    PubMed

    Liu, Zhiguo; Stromberg, David; Liu, Xuming; Liao, Wei; Liu, Yan

    2015-03-21

    A new multiple-stage treatment process was developed via integrating electrocoagulation with biogas pumping to simultaneously reclaim anaerobic digestion effluent and clean up biogas. The 1st stage of electrocoagulation treatment under the preferred reaction condition led to removal efficiencies of 30%, 81%, 37% and >99.9% for total solids, chemical oxygen demand, total nitrogen and total phosphorus, respectively. Raw biogas was then used as a reactant and pumped into the effluent to simultaneously neutralize pH of the effluent and remove H2S in the biogas. The 2nd stage of electrocoagulation treatment on the neutralized effluent showed that under the selected reaction condition, additional 60% and 10% of turbidity and chemical oxygen demand were further removed. The study concluded a dual-purpose approach for the first time to synergistically combine biogas purification and water reclamation for anaerobic digestion system, which well addresses the downstream challenges of anaerobic digestion technology. PMID:25540943

  16. Carbon sequestration in European soils through straw incorporation: limitations and alternatives.

    PubMed

    Powlson, D S; Riche, A B; Coleman, K; Glendining, M J; Whitmore, A P

    2008-01-01

    We compared alternate uses of cereal straw (4.25t dry matter ha(-1) containing 1.7t carbon (C)) for their effectiveness in relation to climate change mitigation. The scenarios were (1) incorporation into soil to increase soil organic carbon (SOC) content ("carbon sequestration") and (2) combustion to generate electricity. The Rothamsted Carbon Model was used to estimate SOC accumulation in a silty clay loam soil under the climatic conditions of north-west Europe. Using straw for electricity generation saved seven times more CO2 than from SOC accumulation. This comparison assumed that electricity from straw combustion displaced that generated from coal and used the mean annual accumulation of SOC over 100yr. SOC increased most rapidly in the early years, but then more slowly as a new equilibrium value was approached. We suggest that increased SOC from straw incorporation does not represent genuine climate change mitigation through carbon sequestration. In Europe, most straw not already incorporated in the field where it is grown is subsequently returned elsewhere, e.g., after use for animal bedding and production of manure. Only additional retention of C in soil compared to the alternative use represents sequestration. Maintenance of SOC for soil functioning is a more appropriate rationale for returning straw to soil than climate change mitigation. This analysis shows that considerably greater climate change mitigation is achieved through saved CO2 emissions by burning straw for electricity generation, replacing some use of fossil fuel. PMID:18061434

  17. Application of zirconium dioxide nanoparticle sorbent for the clean-up step in post-harvest pesticide residue analysis.

    PubMed

    Uclés, Ana; Herrera López, Sonia; Dolores Hernando, Maria; Rosal, Roberto; Ferrer, Carmen; Fernández-Alba, Amadeo R

    2015-11-01

    The use of yttria-stabilized zirconium dioxide nanoparticles as d-SPE clean-up sorbent for a rapid and sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the determination of post-harvest fungicides (carbaryl, carbendazim, chlorpropham, diphenylamine, ethoxyquin, flutriafol, imazalil, iprodione, methomyl, myclobutanil, pirimiphos-methyl, prochloraz, pyrimethanil, thiabendazole, thiophanate-methyl and tolclofos-methyl) in orange and pear samples has been evaluated and validated. The sample preparation was a modification of the QuEChERS extraction method using yttria-stabilized zirconium dioxide and multi-walled carbon nanotubes (MWCNTs) nanoparticles as the solid phase extraction (d-SPE) clean-up sorbents prior to injecting the ten-fold diluted extracts into the LC system. By using the yttria-stabilized zirconium dioxide extraction method, more recoveries in the 70-120% range were obtained - thus this method was used for the validation. Quantification was carried out using a matrix-matched calibration curve which was linear in the 1-500 µg kg(-1) range for almost all the pesticides studied. The validated limit of quantification was 10 µg kg(-1) for most of the studied compounds, except chlorpropham, ethoxyquin and thiophanate-methyl. Pesticide recoveries at the 10 and 100 µg kg(-1) concentration levels were satisfactory, with values between 77% and 120% and relative standard deviations (RSD) lower than 10% (n=5). The developed method was applied for the determination of selected fungicides in 20 real orange and pear samples. Four different pesticide residues were detected in 10 of these commodities; 20% of the samples contained pesticide residues at a quantifiable level (equal to or above the LOQs) for at least one pesticide residue. The most frequently-detected pesticide residues were: carbendazim, thiabendazole and imazalil-all were below the MRL. The highest concentration found was imazalil at 1175 µg kg

  18. Separation techniques for the clean-up of radioactive mixed waste for ICP-AES/ICP-MS analysis

    SciTech Connect

    Swafford, A.M.; Keller, J.M.

    1993-03-17

    Two separation techniques were investigated for the clean-up of typical radioactive mixed waste samples requiring elemental analysis by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) or Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). These measurements frequently involve regulatory or compliance criteria which include the determination of elements on the EPA Target Analyte List (TAL). These samples usually consist of both an aqueous phase and a solid phase which is mostly an inorganic sludge. Frequently, samples taken from the waste tanks contain high levels of uranium and thorium which can cause spectral interferences in ICP-AES or ICP-MS analysis. The removal of these interferences is necessary to determine the presence of the EPA TAL elements in the sample. Two clean-up methods were studied on simulated aqueous waste samples containing the EPA TAL elements. The first method studied was a classical procedure based upon liquid-liquid extraction using tri-n- octylphosphine oxide (TOPO) dissolved in cyclohexane. The second method investigated was based on more recently developed techniques using extraction chromatography; specifically the use of a commercially available Eichrom TRU[center dot]Spec[trademark] column. Literature on these two methods indicates the efficient removal of uranium and thorium from properly prepared samples and provides considerable qualitative information on the extraction behavior of many other elements. However, there is a lack of quantitative data on the extraction behavior of elements on the EPA Target Analyte List. Experimental studies on these two methods consisted of determining whether any of the analytes were extracted by these methods and the recoveries obtained. Both methods produced similar results; the EPA target analytes were only slightly or not extracted. Advantages and disadvantages of each method were evaluated and found to be comparable.

  19. Separation techniques for the clean-up of radioactive mixed waste for ICP-AES/ICP-MS analysis

    SciTech Connect

    Swafford, A.M.; Keller, J.M.

    1993-03-17

    Two separation techniques were investigated for the clean-up of typical radioactive mixed waste samples requiring elemental analysis by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) or Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). These measurements frequently involve regulatory or compliance criteria which include the determination of elements on the EPA Target Analyte List (TAL). These samples usually consist of both an aqueous phase and a solid phase which is mostly an inorganic sludge. Frequently, samples taken from the waste tanks contain high levels of uranium and thorium which can cause spectral interferences in ICP-AES or ICP-MS analysis. The removal of these interferences is necessary to determine the presence of the EPA TAL elements in the sample. Two clean-up methods were studied on simulated aqueous waste samples containing the EPA TAL elements. The first method studied was a classical procedure based upon liquid-liquid extraction using tri-n- octylphosphine oxide (TOPO) dissolved in cyclohexane. The second method investigated was based on more recently developed techniques using extraction chromatography; specifically the use of a commercially available Eichrom TRU{center_dot}Spec{trademark} column. Literature on these two methods indicates the efficient removal of uranium and thorium from properly prepared samples and provides considerable qualitative information on the extraction behavior of many other elements. However, there is a lack of quantitative data on the extraction behavior of elements on the EPA Target Analyte List. Experimental studies on these two methods consisted of determining whether any of the analytes were extracted by these methods and the recoveries obtained. Both methods produced similar results; the EPA target analytes were only slightly or not extracted. Advantages and disadvantages of each method were evaluated and found to be comparable.

  20. Total soil DNA quantification as an alternative microbial biomass determination approach

    NASA Astrophysics Data System (ADS)

    Semenov, Mikhail

    2015-04-01

    .87 indicated slight (about 13%) underestimation of microbial biomass-C obtained by the CFE approach. Thus, quantification of microbial dsDNA is an alternative option to determine soil microbial biomass under extreme conditions, e.g., in frozen and alkaline soils. In contrast to approaches based on indirect characteristics (respiration, etc.), the DNA-based approach enables evaluating microbial biomass using the immediate content of basic cell compounds universal to all living organisms. This research was supported by the Russian Science Foundation, Project No 14-14-00625.

  1. Effects of alternating wetting and drying versus continuous flooding on chromium fate in paddy soils.

    PubMed

    Xiao, Wendan; Ye, Xuezhu; Yang, Xiaoe; Li, Tingqiang; Zhao, Shouping; Zhang, Qi

    2015-03-01

    Anthropogenic chromium (Cr) pollution in soils poses a great threat to human health through the food chain. It is imperative to understand Cr fate under the range of conditions suitable for rice growth. In this study, the effects of irrigation managements on dynamics of porewater Cr(VI) concentrations in rice paddies and Cr distribution in rice were investigated with pot experiments under greenhouse conditions. Soil redox potential in continuous flooding (CF) treatments showed that reducing conditions remained for the whole duration of rice growing period, while soil redox potential in alternating wetting and drying (AWD) treatments showed that soil conditions alternately changed between reducing and oxic. As soil redox potential is an important factor affecting Cr(VI) reduction in paddy soils, dynamics of Cr(VI) concentration were clearly different under different irrigation managements. In CF treatments, porewater Cr(VI) concentrations decreased with time after planting, while in AWD treatments porewater Cr(VI) concentrations were increased and decreased alternately response to the irrigation cycles. Chromium(VI) concentrations in the CF treatments were lower than those in AWD treatments for most part of rice-growing season. Moreover, Cr concentrations in rice tissues were significantly influenced by irrigation with relatively higher values in the AWD treatments, which might be attributed to the higher porewater Cr(VI) concentrations in AWD treatments. Therefore, it would be better to use CF than AWD management in Cr-contaminated paddy soils to reduce Cr accumulation in rice, and thus to reduce the potential risk to human health. PMID:25546832

  2. Screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil

    SciTech Connect

    Shem, L.M.; Ballou, S.W.; Besmer, M.G.

    1996-12-31

    As part of the Rocky Mountain Arsenal (RMA) Remedial Investigation/Feasibility Study, RMA has contracted Argonne National Laboratory to investigate potential remedial alternatives for the cleanup of agent-contaminated soils. The chemical agents of concern include levinstein mustard, lewisite, sarin, and VX. This investigation has been initially divided into three phases: (1) a literature search to determine what, if any, previous studies have been conducted; (2) a technologies-screening critique of remedial technologies as alternatives to incineration; and (3) an investigation of promising alternatives on RMA soil at the laboratory and bench-scale levels. This paper summarizes the document produced as a result of the technologies screening. The purpose of the document was to determine the applicability of 25 technologies to remediation of agent-contaminated soil for a general site. Technologies were critiqued on the basis of applicability to soil type, applicability to the agents of concern at RMA, applicability to other types of contaminants, cost of the treatment, current status of the technology, and residuals produced.

  3. Cleaning Up the Environment

    ERIC Educational Resources Information Center

    Pruett, Don; Pruett, Lindsay

    2005-01-01

    Environmental community service projects provide many opportunities for students to help the environment and connect with their communities. In Washington State, students are allowed to obtain a high school varsity letter in community service if they complete over 150 community service hours in a calendar year. To help students toward this goal,…

  4. CLEAN-UP Act

    THOMAS, 112th Congress

    Sen. Mikulski, Barbara A. [D-MD

    2011-05-12

    05/12/2011 Read twice and referred to the Committee on Homeland Security and Governmental Affairs. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  5. Cleaning up Floor Care.

    ERIC Educational Resources Information Center

    Carr, Richard; McLean, Doug

    1995-01-01

    Discusses how educational-facility maintenance departments can cut costs in floor cleaning through careful evaluation of floor equipment and products. Tips for choosing carpet detergents are highlighted. (GR)

  6. Cleaning Up Your Environment

    ERIC Educational Resources Information Center

    Feldman, Sandra

    2004-01-01

    In this article the author discusses how inadequate ventilation, poor air quality, mold and other conditions can have a detrimental impact on the health of students and school staff. She states that, these unsafe environmental conditions can cause a negative effect on students' health as well as their achievement. Furthermore, she discusses…

  7. Oil spill clean up

    SciTech Connect

    Claxton, L.D.; Houk, V.S.; Williams, R.; Kremer, F.

    1991-01-01

    Due to the consideration of bioremediation for oil spills, it is important to understand the ecological and human health implications of bioremediation efforts. During biodegradation, the toxicity of the polluting material may actually increase upon the conversion of non-toxic constituents to toxic species. Also, toxic compounds refractory to biological degradation may compromise the effectiveness of the treatment technique. In the study, the Salmonella mutagenicity assay showed that both the Prudhoe Bay crude oil and its weathered counterpart collected from oil-impacted water were weakly mutagenic. Results also showed that the mutagenic components were depleted at a faster rate than the overall content of organic material.

  8. Clean Up after Yourself.

    PubMed

    Lepelley, Alice; Ghosh, Sankar

    2016-03-01

    NLRP3 inflammasome activation is accompanied by induction of mitochondrial damage. In the current issue of Cell, Zhong et al. describe an intracellular mechanism orchestrated by NF-κB to remove inflammasome-activating damaged mitochondria and prevent pathologic inflammation. PMID:26942667

  9. Cleaning Up High.

    ERIC Educational Resources Information Center

    Rittner-Heir, Robbin M.

    2001-01-01

    Discusses cleaning techniques and equipment for areas in a school that are hard to reach, such as the high spacious ceilings, the tall windows of a school atrium, and high points in gymnasiums and auditoriums. (GR)

  10. Hyperaccumulator oilcake manure as an alternative for chelate-induced phytoremediation of heavy metals contaminated alluvial soils.

    PubMed

    Mani, Dinesh; Kumar, Chitranjan; Patel, Niraj Kumar

    2015-01-01

    The ability of hyperaccumulator oilcake manure as compared to chelates was investigated by growing Calendula officinalis L for phytoremediation of cadmium and lead contaminated alluvial soil. The combinatorial treatment T6 [2.5 g kg(-1) oilcake manure+5 mmol kg(-1) EDDS] caused maximum cadmium accumulation in root, shoot and flower up to 5.46, 4.74 and 1.37 mg kg(-1) and lead accumulation up to 16.11, 13.44 and 3.17 mg kg(-1), respectively at Naini dump site, Allahabad (S3). The treatment showed maximum remediation efficiency for Cd (RR=0.676%) and Pb (RR=0.202%) at Mumfordganj contaminated site (S2). However, the above parameters were also observed at par with the treatment T5 [2.5 g kg(-1) oilcake manure +2 g kg(-1) humic acid]. Applied EDDS altered chlorophyll-a, chlorophyll-b, and carotene contents of plants while application of oilcake manure enhanced their contents in plant by 3.73-8.65%, 5.81-17.65%, and 7.04-17.19%, respectively. The authors conclude that Calendula officinalis L has potential to be safely grown in moderately Cd and Pb-contaminated soils and application of hyperaccumulator oilcake manure boosts the photosynthetic pigments of the plant, leading to enhanced clean-up of the cadmium and lead-contaminated soils. Hence, the hyperaccumulator oilcake manure should be preferred over chelates for sustainable phytoremediation through soil-plant rhizospheric process. PMID:25397984

  11. Application of Polymeric Agents for Improved Soil Decontamination

    SciTech Connect

    Heiser, John

    2008-09-30

    The objectives of the Thrust II project include optimization of the technology for PO Mayak soils, identification of clean up requirements, design and construction of a mobile production-scale process system, installation and deployment of the soil washing technology.

  12. Electrical field assisted matrix solid phase dispersion as a powerful tool to improve the extraction efficiency and clean-up of fluoroquinolones in bovine milk.

    PubMed

    da Silva, Mariana Cristina; Orlando, Ricardo Mathias; Faria, Adriana Ferreira

    2016-08-26

    This work presents a new method by electrical matrix solid phase dispersion for the extraction and clean-up of marbofloxacin, ofloxacin, norfloxacin, ciprofloxacin, enrofloxacin, difloxacin and sarafloxacin in bovine milk. Composition and pH of the eluent, applied electrical potential and polarity were optimized by experimental designs. The combination of the chromatographic and electrophoretic mechanisms allowed the extraction and clean-up in one step with low organic solvent consumption, high extraction throughput and elution automation. Linearity, precision, trueness and limit of quantification were evaluated and provided values in accordance with other methods recently developed for the analysis of fluoroquinolones in milk. This technique proved to be promising for the extraction and clean-up of ionizable analytes in different milk matrices. PMID:27492598

  13. Effect of alternating bioremediation and electrokinetics on the remediation of n-hexadecane-contaminated soil

    PubMed Central

    Wang, Sa; Guo, Shuhai; Li, Fengmei; Yang, Xuelian; Teng, Fei; Wang, Jianing

    2016-01-01

    This study demonstrated the highly efficient degradation of n-hexadecane in soil, realized by alternating bioremediation and electrokinetic technologies. Using an alternating technology instead of simultaneous application prevented competition between the processes that would lower their efficiency. For the consumption of the soil dissolved organic matter (DOM) necessary for bioremediation by electrokinetics, bioremediation was performed first. Because of the utilization and loss of the DOM and water-soluble ions by the microbial and electrokinetic processes, respectively, both of them were supplemented to provide a basic carbon resource, maintain a high electrical conductivity and produce a uniform distribution of ions. The moisture and bacteria were also supplemented. The optimal DOM supplement (20.5 mg·kg−1 glucose; 80–90% of the total natural DOM content in the soil) was calculated to avoid competitive effects (between the DOM and n-hexadecane) and to prevent nutritional deficiency. The replenishment of the water-soluble ions maintained their content equal to their initial concentrations. The degradation rate of n-hexadecane was only 167.0 mg·kg−1·d−1 (1.9%, w/w) for the first 9 days in the treatments with bioremediation or electrokinetics alone, but this rate was realized throughout the whole process when the two technologies were alternated, with a degradation of 78.5% ± 2.0% for the n-hexadecane after 45 days of treatment. PMID:27032838

  14. Effect of alternating bioremediation and electrokinetics on the remediation of n-hexadecane-contaminated soil.

    PubMed

    Wang, Sa; Guo, Shuhai; Li, Fengmei; Yang, Xuelian; Teng, Fei; Wang, Jianing

    2016-01-01

    This study demonstrated the highly efficient degradation of n-hexadecane in soil, realized by alternating bioremediation and electrokinetic technologies. Using an alternating technology instead of simultaneous application prevented competition between the processes that would lower their efficiency. For the consumption of the soil dissolved organic matter (DOM) necessary for bioremediation by electrokinetics, bioremediation was performed first. Because of the utilization and loss of the DOM and water-soluble ions by the microbial and electrokinetic processes, respectively, both of them were supplemented to provide a basic carbon resource, maintain a high electrical conductivity and produce a uniform distribution of ions. The moisture and bacteria were also supplemented. The optimal DOM supplement (20.5 mg·kg(-1) glucose; 80-90% of the total natural DOM content in the soil) was calculated to avoid competitive effects (between the DOM and n-hexadecane) and to prevent nutritional deficiency. The replenishment of the water-soluble ions maintained their content equal to their initial concentrations. The degradation rate of n-hexadecane was only 167.0 mg·kg(-1)·d(-1) (1.9%, w/w) for the first 9 days in the treatments with bioremediation or electrokinetics alone, but this rate was realized throughout the whole process when the two technologies were alternated, with a degradation of 78.5% ± 2.0% for the n-hexadecane after 45 days of treatment. PMID:27032838

  15. Effect of alternating bioremediation and electrokinetics on the remediation of n-hexadecane-contaminated soil

    NASA Astrophysics Data System (ADS)

    Wang, Sa; Guo, Shuhai; Li, Fengmei; Yang, Xuelian; Teng, Fei; Wang, Jianing

    2016-04-01

    This study demonstrated the highly efficient degradation of n-hexadecane in soil, realized by alternating bioremediation and electrokinetic technologies. Using an alternating technology instead of simultaneous application prevented competition between the processes that would lower their efficiency. For the consumption of the soil dissolved organic matter (DOM) necessary for bioremediation by electrokinetics, bioremediation was performed first. Because of the utilization and loss of the DOM and water-soluble ions by the microbial and electrokinetic processes, respectively, both of them were supplemented to provide a basic carbon resource, maintain a high electrical conductivity and produce a uniform distribution of ions. The moisture and bacteria were also supplemented. The optimal DOM supplement (20.5 mg·kg‑1 glucose; 80–90% of the total natural DOM content in the soil) was calculated to avoid competitive effects (between the DOM and n-hexadecane) and to prevent nutritional deficiency. The replenishment of the water-soluble ions maintained their content equal to their initial concentrations. The degradation rate of n-hexadecane was only 167.0 mg·kg‑1·d‑1 (1.9%, w/w) for the first 9 days in the treatments with bioremediation or electrokinetics alone, but this rate was realized throughout the whole process when the two technologies were alternated, with a degradation of 78.5% ± 2.0% for the n-hexadecane after 45 days of treatment.

  16. Common plants as alternative analytical tools to monitor heavy metals in soil

    PubMed Central

    2012-01-01

    Background Herbaceous plants are common vegetal species generally exposed, for a limited period of time, to bioavailable environmental pollutants. Heavy metals contamination is the most common form of environmental pollution. Herbaceous plants have never been used as natural bioindicators of environmental pollution, in particular to monitor the amount of heavy metals in soil. In this study, we aimed at assessing the usefulness of using three herbaceous plants (Plantago major L., Taraxacum officinale L. and Urtica dioica L.) and one leguminous (Trifolium pratense L.) as alternative indicators to evaluate soil pollution by heavy metals. Results We employed Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) to assess the concentration of selected heavy metals (Cu, Zn, Mn, Pb, Cr and Pd) in soil and plants and we employed statistical analyses to describe the linear correlation between the accumulation of some heavy metals and selected vegetal species. We found that the leaves of Taraxacum officinale L. and Trifolium pratense L. can accumulate Cu in a linearly dependent manner with Urtica dioica L. representing the vegetal species accumulating the highest fraction of Pb. Conclusions In this study we demonstrated that common plants can be used as an alternative analytical tool for monitoring selected heavy metals in soil. PMID:22594441

  17. Physicochemical regeneration of high silica zeolite Y used to clean-up water polluted with sulfonamide antibiotics.

    PubMed

    Braschi, I; Blasioli, S; Buscaroli, E; Montecchio, D; Martucci, A

    2016-05-01

    High silica zeolite Y has been positively evaluated to clean-up water polluted with sulfonamides, an antibiotic family which is known to be involved in the antibiotic resistance evolution. To define possible strategies for the exhausted zeolite regeneration, the efficacy of some chemico-physical treatments on the zeolite loaded with four different sulfonamides was evaluated. The evolution of photolysis, Fenton-like reaction, thermal treatments, and solvent extractions and the occurrence in the zeolite pores of organic residues eventually entrapped was elucidated by a combined thermogravimetric (TGA-DTA), diffractometric (XRPD), and spectroscopic (FT-IR) approach. The chemical processes were not able to remove the organic guest from zeolite pores and a limited transformation on embedded molecules was observed. On the contrary, both thermal treatment and solvent extraction succeeded in the regeneration of the zeolite loaded from deionized and natural fresh water. The recyclability of regenerated zeolite was evaluated over several adsorption/regeneration cycles, due to the treatment efficacy and its stability as well as the ability to regain the structural features of the unloaded material. PMID:27155437

  18. Feasibility of photocatalytic oxidation for wastewater clean-up and reuse. Report for 4 Mar 81-31 Mar 81

    SciTech Connect

    Peyton, G.R.; DeBerry, D.W.

    1981-01-01

    A feasibility study has been conducted on a new treatment technology for the destruction of pollutant compounds in wastewater. The process uses solar energy to drive an oxidation which is photocatalyzed at the surface of a semiconductor powder. The process is being investigated particularly for water clean-up prior to industrial resuse, because of its non-energy-intensive nature. Five compounds (chloroform, dimethylamine, methanol, phenol, and ammonia) were used as model substrates, and removal at several pH values, using three different semiconductors (TiO2, ZnO, and Fe2O3) was investigated in the laboratory, using a xenon lamp to simulate solar radiation. While Fe2O3 was found to be ineffective, both ZnO and TiO2 catalyzed the removal of all compounds. Ammonia was not very effectively destroyed, but all four organic compounds experienced 30-50% removal in six hours at intensities slightly above that of normal solar radiation. Favorable cases were confirmed using sunlight. Quantum efficiencies for both sets of experiments were 13-20% for TiO2 and 4-7% using ZnO. Estimated treatment cost for a 1 mgd stream using laboratory conditions ranged from $0.18-$0.72 per thousand gallons, depending on the values of engineering parameters which were not investigated in this feasibility study.

  19. Does further clean-up reduce the matrix enhancement effect in gas chromatographic analysis of pesticide residues in food?

    PubMed

    Schenck, F J; Lehotay, S J

    2000-01-28

    Sample extracts of apples, peas, green beans, oranges, raspberries, clementines, carrots, and wheat obtained using the Food and Drug Administration (acetone extraction) and Canadian Pest Management Regulatory Agency (acetonitrile extraction) multiresidue methods for pesticides were subjected to clean-up using different solid-phase extraction (SPE) cartridges in an attempt to reduce or eliminate the matrix enhancement effect. The matrix enhancement effect is related to the blocking of active sites on the injector liner by matrix components, thereby increasing signal in the presence of matrix versus standards in solvent in which the pesticides themselves interact with the active sites. Graphitized carbon black (GCB) was often used in combination with various anion-exchange SPE cartridges. The extracts were then spiked with organophosphorus insecticides. These process standards were then compared to standards in acetone of the same concentration using gas chromatography with flame photometric detection or ion trap mass spectrometric detection. Sample matrix enhancement varied from little to no effect for some pesticides (e.g. chlorpyrifos, malathion) to >200% in the case of certain susceptible pesticides. The GCB removed color components but showed little effect in reducing matrix enhancement by itself. The anion-exchange cartridges in combination with GCB or not, substantially reduced the matrix enhancement effect but did not eliminate it. PMID:10677079

  20. Lignin decomposition and microbial community in paddy soils: effects of alternating redox conditions

    NASA Astrophysics Data System (ADS)

    Cerli, Chiara; Liu, Qin; Hanke, Alexander; Kaiser, Klaus; Kalbitz, Karsten

    2013-04-01

    Paddy soils are characterised by interchanging cycles of anaerobic and aerobic conditions. Such fluctuations cause continuous changes in soil solution chemistry as well as in the composition and physiological responses of the microbial community. Temporary deficiency in oxygen creates conditions favourable to facultative or obligates anaerobic bacteria, while aerobic communities can thrive in the period of water absence. These alterations can strongly affect soil processes, in particular organic matter (OM) accumulation and mineralization. In submerged soils, lignin generally constitutes a major portion of the total OM because of hampered degradation under anoxic conditions. The alternating redox cycles resulting from paddy soil management might promote both degradation and preservation of lignin, affecting the overall composition and reactivity of total and dissolved OM. We sampled soils subjected to cycles of anoxic (rice growing period) and oxic (harvest and growth of other crops) conditions since 700 and 2000 years. We incubated suspended Ap material, sampled from the two paddy plus two corresponding non-paddy control soils under oxic and anoxic condition, for 3 months, interrupted by a short period of three weeks (from day 21 to day 43) with reversed redox conditions. At each sampling time (day 2, 21, 42, 63, 84), we determined lignin-derived phenols (by CuO oxidation) as well as phospholipids fatty acids contents and composition. We aimed to highlight changes in lignin decomposition as related to the potential rapid changes in microbial community composition. Since the studied paddy soils had a long history of wet rice cultivation, the microbial community should be well adapted to interchanging oxic and anoxic cycles, therefore fully expressing its activity at both conditions. In non-paddy soil changes in redox conditions caused modification of quantity and composition of the microbial community. On the contrary, in well-established paddy soils the microbial

  1. A LC/UV/Vis method for determination of cyanocobalamin in multivitamin dietary supplements with on-line sample clean-up

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A HPLC-UV method using a two-column strategy with a switching valve for on-line sample clean-up was developed for the determination of cyanocobalamin (CN-CBL-vitamin B12, in dietary supplements. The method uses two columns, an Agilent Zorbax C8 (150 mm x 4.6 mm, 5 um particle) reversed-phase column...

  2. Multiplug filtration clean-up with multiwalled carbon nanotubes in the analysis of pesticide residues using LC-ESI-MS/MS.

    PubMed

    Zhao, Pengyue; Fan, Sufang; Yu, Chuanshan; Zhang, Junyan; Pan, Canping

    2013-10-01

    A novel design for a rapid clean-up method was developed for the analysis of pesticide residues in fruit and vegetables followed by LC-ESI-MS/MS. The acetonitrile-based sample extraction technique was used to obtain the extracts, and further clean-up was carried out by applying the streamlined procedure on a multiplug filtration clean-up column coupled with a syringe. The sorbent used for clean-up in this research is multiwalled carbon nanotubes, which was mixed with anhydrous magnesium sulfate to remove water from the extracts. This method was validated on 40 representative pesticides and apple, cabbage, and potato sample matrices spiked at two concentration levels of 10 and 100 μg/kg. It exhibited recoveries between 71 and 117% for most pesticides with RSDs < 15%. Matrix-matched calibrations were performed with the coefficients of determination >0.995 for most studied pesticides between concentration levels of 10-500 μg/L. The LOQs for 40 pesticides ranged from 2 to 50 μg/kg. The developed method was successfully applied to the determination of pesticide residues in market fruit and vegetable samples. PMID:23939876

  3. EVALUATION OF GEL PERMEATION CHROMATOGRAPHY FOR CLEAN UP OF HUMAN ADIPOSE TISSUE SAMPLES FOR GC/MS ANALYSIS OF PESTICIDES AND OTHER CHEMICALS

    EPA Science Inventory

    Gel permeation chromatography (GPC) has been evaluated for clean up of human adipose tissue sample extracts in preparation for confirmatory analysis by gas chromatography-mass spectrometry (GC/MS). Studies were conducted with standard solutions, fortified chicken fat, and actual ...

  4. Separation and determination of citrinin in corn using HPLC fluorescence detection assisted by molecularly imprinted solid phase extraction clean-up

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A liquid chromatography based method to detect citrinin in corn was developed using molecularly imprinted solid phase extraction (MISPE) sample clean-up. Molecularly imprinted polymers were synthesized using 1,4-dihydroxy-2-naphthoic acid as the template and an amine functional monomer. Density func...

  5. Analysis of sterigmatocystin in cereals, animal feed, seeds, beer and cheese by immunoaffinity column clean-up and HPLC and LC-MS/MS quantification.

    PubMed

    Marley, Elaine; Brown, Phyllis; Mackie, Jennifer; Donnelly, Carol; Wilcox, Joyce; Pietri, Amedeo; Macdonald, Susan

    2015-01-01

    A method is reported for the analysis of sterigmatocystin in various food and feed matrices using a commercial sterigmatocystin immunoaffinity column (IAC) for sample clean-up prior to HPLC analysis by UV with mass spectrometric detection (LC-MS/MS). Cereals (wheat, oats, rye, maize and rice), sunflower seeds and animal feed were spiked with sterigmatocystin at levels from 0.75 to 50 µg kg(-1) to establish method performance. Using acetonitrile/water extraction followed by IAC clean-up, and analysis by HPLC with detection at 325 nm, recoveries ranged from 68% to 106%, with repeatability from 4.2% to 17.5%. The limit of quantification with UV detection in these matrices was 1.5 µg kg(-1). For the analysis of beer and cheese the sample preparation prior to IAC clean-up was changed to accommodate the different properties of the matrix, prior to analysis by LC-MS/MS. For beer and cheese spiked at 5.0 µg kg(-1) the recoveries were 94% and 104%, and precision (RSDs) were 1.9% and 2.9% respectively. The limits of quantification by LC-MS/MS in beer and cheese were 0.02 and 0.6 µg kg(-1) respectively. The sterigmatocystin IAC was demonstrated to provide an efficient clean-up of various matrices to enable this mycotoxin to be determined by either HPLC with UV detection or LC-MS/MS. PMID:26515281

  6. Development And Implementation Of A Strategic Technical Baseline Approach For Nuclear Decommissioning And Clean Up Programmes In The UK

    SciTech Connect

    Brownridge, M.; Ensor, B.

    2008-07-01

    The NDA mission as set out within the Energy Act 2004 and stated in the NDA strategy is clear: - 'to deliver a world class programme of safe, cost-effective, accelerated and environmentally responsible decommissioning of the UK's civil nuclear legacy in an open and transparent manner and with due regard to the socio-economic impacts on our communities. Critical to achieving the NDA main objective and overall mission is to accelerate and deliver clean-up programmes through the application of appropriate and innovative technology. The NDA remit also requires us to secure good practice by contractors and carry out and promote research into matters relating to the decommissioning and clean up of nuclear installations and sites. NDA have defined a strategic approach for the underpinning of operational and decommissioning activities where each nuclear site is required to write within the Life Time Plans (LTP) the proposed technical baseline for those activities. This enables the robustness of the activities to be assessed, the gaps and opportunities and accompanying Research and Developments (R and D) requirements to be highlighted and investment to be targeted at key technical issues. NDA also supports the development of a commercial framework where innovation is encouraged and improvements can be demonstrated against the technical baseline. In this paper we will present NDA's overall strategic approach, the benefits already realised and highlight the areas for continued development. In conclusion: The development and implementation of a strategic approach to robustly underpin the technical components of the lifetime plans for operational and decommissioning activities on NDA sites has been extremely successful. As well as showing how mature technology assumptions are and where the key gaps and risks are it has also provided a method for highlighting opportunities to improve on that baseline. The use of a common template across all NDA LTPs has enabled direct comparison

  7. An Alternative Approach to Assess the Habitat Selection of Folsomia candida in Contaminated Soils.

    PubMed

    Bori, Jaume; Riva, Maria Carme

    2015-11-01

    Avoidance tests with collembolans provide a quick assessment of soil quality. However, some parameters of the procedure can be modified in order to increase its performance. In this study we assessed the tendency of Folsomia candida to avoid soils contaminated with boric acid [350-700-1400-2800-5600 mg/kg soil dry weight (dw)], phenmedipham (35-70-140-280 mg/kg dw) or petroleum hydrocarbons (1312-1838-2625-3675-5250 mg/kg dw) by preferring an untreated soil. Two separate methodologies were applied, the one presented in the ISO standard 17512:2 and a modified version of the Petri dish method that allowed data acquisition after 2, 24 and 48 h of exposure. After combining data from three separate trials, effective median concentration values (EC50) from the presented method were lower and showed similar or less variability than those from the ISO procedure, suggesting the modified protocol as a suitable alternative screening tool. PMID:26350730

  8. Multiresidue determination of pesticides and pesticide metabolites in soil

    SciTech Connect

    Mogadati, P.S.; Rosen, J.D.

    1995-12-31

    Methods for the multiresidue extraction, cleanup and GC/MS determination of 142 pesticides and pesticide metabolites in soil have been developed. The use of solid phase extraction cartridges makes it possible to clean up the soil sufficiently so that the equivalent of 40 mg. soil may be injected onto the GC capillary column without overloading or harming the column. Combining this clean-up method with chemical ionization ion trap detection allowed for very low limits of detection.

  9. A Strategy for Skills to meet the demands of Nuclear Decommissioning and Clean-up in the UK

    SciTech Connect

    Brownridge, M.; Ensor, B.

    2008-07-01

    The NDA remit as set out within the Energy Act includes - 'to ensure the availability of skills required to deliver the overall decommissioning and nuclear clean-up mission'. The NDA approach to meeting their statutory obligation is by: - finding the best ways of re-training, re-skilling or re-deploying people in a way that encourages a more flexible workforce; - identifying and communicating the skills and workforce requirements to deliver the mission; and - developing the infrastructure and capability initiatives in line with long term needs, for example, a National Skills Academy for Nuclear, Nuclear Institute, National Graduate Scheme, and - developing locally specific provision. Firstly, NDA has set the requirement for nuclear sites to write down within the Life Time Plans (LTP), at a high level, their Site Skills Strategies; furthermore, a National Skills Working Group has been established to develop tactical cross sector solutions to support the NDA's Skills Strategy. In support of the short, medium and long term needs to meet demands of the NDA sites and the nuclear decommissioning sector, as well as being aware of the broader nuclear sector, investments have been made in infrastructure and skills programmes such as: - A National Skills Academy for Nuclear - including UK wide representation of the whole nuclear sector; - A Nuclear Institute in partnership with the University of Manchester focussing on world class research and skills in Radiation Sciences and Decommissioning Engineering; - Post Graduate sponsorship for decommissioning related projects; - A National Graduate Scheme partnership with nuclear related employers; - Vocational qualifications and Apprenticeship Schemes - Engaging 14-19 year old students to encourage the take up of Science related subjects; and - A sector wide 'Skills Passport'. In conclusion: The skills challenge has many dimensions but requires addressing due to the clear link to improved business performance and the availability

  10. A Membrane-Based Electro-Separation Method (MBES) for Sample Clean-Up and Norovirus Concentration

    PubMed Central

    Kang, Wei; Cannon, Jennifer L.

    2015-01-01

    Noroviruses are the leading cause of acute gastroenteritis and foodborne illnesses in the United States. Enhanced methods for detecting noroviruses in food matrices are needed as current methods are complex, labor intensive and insensitive, often resulting in inhibition of downstream molecular detection and inefficient recovery. Membrane-based electro-separation (MBES) is a technique to exchange charged particles through a size-specific dialysis membrane from one solution to another using electric current as the driving force. Norovirus has a net negative surface charge in a neutrally buffered environment, so when placed in an electric field, it moves towards the anode. It can then be separated from the cathodic compartment where the sample is placed and then collected in the anodic compartment for downstream detection. In this study, a MBES-based system was designed, developed and evaluated for concentrating and recovering murine norovirus (MNV-1) from phosphate buffer. As high as 30.8% MNV-1 migrated from the 3.5 ml sample chamber to the 1.5 ml collection chamber across a 1 μm separation membrane when 20 V was applied for 30 min using 20 mM sodium phosphate with 0.01% SDS (pH 7.5) as the electrolyte. In optimization of the method, weak applied voltage (20 V), moderate duration (30 min), and low ionic strength electrolytes with SDS addition were needed to increase virus movement efficacy. The electric field strength of the system was the key factor to enhance virus movement, which could only be improved by shortening the electrodes distance, instead of increasing system applied voltage because of virus stability. This study successfully demonstrated the norovirus mobility in an electric field and migration across a size-specific membrane barrier in sodium phosphate electrolyte. With further modification and validation in food matrixes, a novel, quick, and cost-effective sample clean-up technique might be developed to separate norovirus particles from food

  11. Use of deep soil mixing as an alternate verticle barrier to slurry walls

    SciTech Connect

    Miller, A.D.

    1997-12-31

    Slurry walls have become an accepted subsurface remediation technique to contain contaminated zones. However, situations develop where conventional slurry wall excavation techniques are not suitable. The use of conventional containment wall construction methods may involve removal and disposal of contaminated soils, stability concerns and the risk of open excavations. For these reasons, other installation techniques have received further consideration. Deep Soil Mixing (DSM) has emerged as a viable alternative to conventional slurry wall techniques. In situations dictating limited soil removal for contamination or stability concerns, or where space is a limitation, DSM can be used for installation of the barrier. Proper installation of a DSM wall requires sufficient monitoring and sampling to evaluate the continuity, mixing effectiveness, permeability and key into the confining layer. This paper describes a case study where DSM was used to cross major highways to avoid open excavation, and along slopes to reduce stability concerns. The DSM barrier was tied to an existing conventional slurry wall that had been installed in more stable areas without highway traffic.

  12. "Trees Live on Soil and Sunshine!"--Coexistence of Scientific and Alternative Conception of Tree Assimilation.

    PubMed

    Thorn, Christine Johanna; Bissinger, Kerstin; Thorn, Simon; Bogner, Franz Xaver

    2016-01-01

    Successful learning is the integration of new knowledge into existing schemes, leading to an integrated and correct scientific conception. By contrast, the co-existence of scientific and alternative conceptions may indicate a fragmented knowledge profile. Every learner is unique and thus carries an individual set of preconceptions before classroom engagement due to prior experiences. Hence, instructors and teachers have to consider the heterogeneous knowledge profiles of their class when teaching. However, determinants of fragmented knowledge profiles are not well understood yet, which may hamper a development of adapted teaching schemes. We used a questionnaire-based approach to assess conceptual knowledge of tree assimilation and wood synthesis surveying 885 students of four educational levels: 6th graders, 10th graders, natural science freshmen and other academic studies freshmen. We analysed the influence of learner's characteristics such as educational level, age and sex on the coexistence of scientific and alternative conceptions. Within all subsamples well-known alternative conceptions regarding tree assimilation and wood synthesis coexisted with correct scientific ones. For example, students describe trees to be living on "soil and sunshine", representing scientific knowledge of photosynthesis mingled with an alternative conception of trees eating like animals. Fragmented knowledge profiles occurred in all subsamples, but our models showed that improved education and age foster knowledge integration. Sex had almost no influence on the existing scientific conceptions and evolution of knowledge integration. Consequently, complex biological issues such as tree assimilation and wood synthesis need specific support e.g. through repeated learning units in class- and seminar-rooms in order to help especially young students to handle and overcome common alternative conceptions and appropriately integrate scientific conceptions into their knowledge profile. PMID

  13. Development of sample clean up methods for the analysis of Mycobacterium tuberculosis methyl mycocerosate biomarkers in sputum extracts by gas chromatography–mass spectrometry

    PubMed Central

    Nicoara, Simona C.; Turner, Nicholas W.; Minnikin, David E.; Lee, Oona Y.-C.; O'Sullivan, Denise M.; McNerney, Ruth; Mutetwa, Reggie; Corbett, Liz E.; Morgan, Geraint H.

    2015-01-01

    A proof of principle gas chromatography–mass spectrometry method is presented, in combination with clean up assays, aiming to improve the analysis of methyl mycocerosate tuberculosis biomarkers from sputum. Methyl mycocerosates are generated from the transesterification of phthiocerol dimycocerosates (PDIMs), extracted in petroleum ether from sputum of tuberculosis suspect patients. When a high matrix background is present in the sputum extracts, the identification of the chromatographic peaks corresponding to the methyl derivatives of PDIMs analytes may be hindered by the closely eluting methyl ether of cholesterol, usually an abundant matrix constituent frequently present in sputum samples. The purification procedures involving solid phase extraction (SPE) based methods with both commercial Isolute-Florisil cartridges, and purpose designed molecularly imprinted polymeric materials (MIPs), resulted in cleaner chromatograms, while the mycocerosates are still present. The clean-up performed on solutions of PDIMs and cholesterol standards in petroleum ether show that, depending on the solvent mix and on the type of SPE used, the recovery of PDIMs is between 64 and 70%, whilst most of the cholesterol is removed from the system. When applied to petroleum ether extracts from representative sputum samples, the clean-up procedures resulted in recoveries of 36–68% for PDIMs, allowing some superior detection of the target analytes. PMID:25728371

  14. I{ Relationship between source clean up and mass flux of chlorinated solvents in low permeability settings with fractures}

    NASA Astrophysics Data System (ADS)

    Bjerg, P. L.; Chambon, J. C.; Christiansen, C. M.; Broholm, M. M.; Binning, P. J.

    2009-04-01

    Groundwater contamination by chlorinated solvents, such as perchloroethylene (PCE), often occurs via leaching from complex sources located in low permeability sediments such as clayey tills overlying aquifers. Clayey tills are mostly fractured, and contamination migrating through the fractures spreads to the low permeability matrix by diffusion. This results in a long term source of contamination due to back-diffusion. Leaching from such sources is further complicated by microbial degradation under anaerobic conditions to sequentially form the daughter products trichloroethylene, cis-dichloroethylene (cis-DCE), vinyl chloride (VC) and ethene. This process can be enhanced by addition of electron donors and/or bioaugmentation and is termed Enhanced Reductive Dechlorination (ERD). This work aims to improve our understanding of the physical, chemical and microbial processes governing source behaviour under natural and enhanced conditions. That understanding is applied to risk assessment, and to determine the relationship and time frames of source clean up and plume response. To meet that aim, field and laboratory observations are coupled to state of the art models incorporating new insights of contaminant behaviour. The long term leaching of chlorinated ethenes from clay aquitards is currently being monitored at a number of Danish sites. The observed data is simulated using a coupled fracture flow and clay matrix diffusion model. Sequential degradation is represented by modified Monod kinetics accounting for competitive inhibition between the chlorinated ethenes. The model is constructed using Comsol Multiphysics, a generic finite- element partial differential equation solver. The model is applied at well characterised field sites with respect to hydrogeology, fracture network, contaminant distribution and microbial processes (lab and field experiments). At one of the study sites (Sortebrovej), the source areas are situated in a clayey till with fractures and

  15. Probabilistic comparison of alternative characterization technologies at the Fernald Uranium-in-Soils Integrated Demonstration Project

    SciTech Connect

    Rautman, C.A.; McGraw, M.A.; Istok, J.D.; Sigda, J.M.; Kaplan, P.G.

    1993-12-31

    The performance of four alternative characterization technologies proposed for use in characterization of surficial uranium contamination in soil at the Incinerator and Drum Baling Areas at the Fernald Environmental Management Project in southwestern Ohio has been evaluated using a probabilistic, risk-based decision-analysis methodology. The basis of comparison is to minimize a computed total cost for environmental cleanup. This total-cost-based approach provides a framework for evaluating the trade-offs among remedial investigation, the remedial design, and the risk of regulatory penalties. The approach explicitly recognizes the value of information provided by remedial investigation; additional measurements are only valuable to the extent that the information they provide reduces total cost.

  16. Alternative methods in the development of pedotransfer functions for soil hydraulic characteristics

    NASA Astrophysics Data System (ADS)

    Merdun, H.

    2010-01-01

    Soil hydraulic properties are needed in the modeling of water flow and solute movement in the vadose zone. Pedotransfer functions (PTFs) have received the attention of many researchers for indirect determination of hydraulic properties from basic soil properties as an alternative to direct measurement. The objective of this study was to compare the performance of cascade forward network (CFN), multiple-linear regression (MLR), and seemingly unrelated regression (SUR) methods using prediction capabilities of point and parametric PTFs developed by these methods. The point PTFs estimated field capacity (FC), permanent wilting point (PWP), available water capacity (AWC), and saturated hydraulic conductivity ( Ks) and the parametric PTFs estimated the van Genuchten retention parameters. A total of 180 soil samples was extracted from the UNSODA database and divided into two groups as 135 for the development and 45 for the validation of the PTFs. The model performances were evaluated with three statistical tools: the maximum error (ME), the model efficiency (EF), and the D index ( D) using the observed and predicted values of a given parameter. Despite the fact that the differences among the three methods in prediction accuracies of the point and parametric PTFs were not statistically significant ( p > 0.05) except θr and α ( p < 0.05) based on the ANOVA test, overall MLR and SUR were somewhat better than CFN in prediction of the point PTFs, whereas CFN performed better than the other two methods in prediction of the parametric PTFs. The F.F values of FC and θr for CFN, MLR, and SUR methods were 0.705. 0.805, 0.795 and 0.356, -0.290, -0.290, respectively, which refer to the best and worst predictions. Properties ( Ks, θr, α) having some difficulty in prediction were better predicted by CFN and SUR methods, where these methods predict all hydraulic properties from basic soil properties simultaneously rather than individually as in MLR. This suggests that multivariate

  17. How do alternative root water uptake models affect the inverse estimation of soil hydraulic parameters and the prediction of evapotranspiration?

    NASA Astrophysics Data System (ADS)

    Gayler, Sebastian; Salima-Sultana, Daisy; Selle, Benny; Ingwersen, Joachim; Wizemann, Hans-Dieter; Högy, Petra; Streck, Thilo

    2016-04-01

    Soil water extraction by roots affects the dynamics and distribution of soil moisture and controls transpiration, which influences soil-vegetation-atmosphere feedback processes. Consequently, root water uptake requires close attention when predicting water fluxes across the land surface, e.g., in agricultural crop models or in land surface schemes of weather and climate models. The key parameters for a successful simultaneous simulation of soil moisture dynamics and evapotranspiration in Richards equation-based models are the soil hydraulic parameters, which describe the shapes of the soil water retention curve and the soil hydraulic conductivity curve. As measurements of these parameters are expensive and their estimation from basic soil data via pedotransfer functions is rather inaccurate, the values of the soil hydraulic parameters are frequently inversely estimated by fitting the model to measured time series of soil water content and evapotranspiration. It is common to simulate root water uptake and transpiration by simple stress functions, which describe from which soil layer water is absorbed by roots and predict when total crop transpiration is decreased in case of soil water limitations. As for most of the biogeophysical processes simulated in crop and land surface models, there exist several alternative functional relationships for simulating root water uptake and there is no clear reason for preferring one process representation over another. The error associated with alternative representations of root water uptake, however, contributes to structural model uncertainty and the choice of the root water uptake model may have a significant impact on the values of the soil hydraulic parameters estimated inversely. In this study, we use the agroecosystem model system Expert-N to simulate soil moisture dynamics and evapotranspiration at three agricultural field sites located in two contrasting regions in Southwest Germany (Kraichgau, Swabian Alb). The Richards

  18. Problems and prospects concerning the phytoremediation of heavy metal polluted soils: A review

    NASA Astrophysics Data System (ADS)

    Koptsik, G. N.

    2014-09-01

    The current state, problems, and prospects of phymoremediation of heavy metal polluted soils are analyzed. The main attention is paid to the phytoextraction and phytostabilization as the most widespread and alternative methods of soil phytoremediation. The efficiency of phymoremediation is related to the natural capability of plants for the accumulation and translocation of metals, their tolerance to a high content of metals, the plant biomass, and the amendments applied. The advantages and disadvantages of phytoremediation as compared to other methods of remediation of polluted soils in situ are considered. Examples of successful phytoextraction and phytomining for cleaning up of contaminated soils in Rasteburg (South Africa) and the phytostabilization of technogenic barrens nearby the copper-nickel plants in Sudbury (Ontario, Canada) and in the Kola Subarctic (Russia) are presented.

  19. Development of sample preparation method for auxin analysis in plants by vacuum microwave-assisted extraction combined with molecularly imprinted clean-up procedure.

    PubMed

    Hu, Yuling; Li, Yuanwen; Zhang, Yi; Li, Gongke; Chen, Yueqin

    2011-04-01

    A novel sample preparation method for auxin analysis in plant samples was developed by vacuum microwave-assisted extraction (VMAE) followed by molecularly imprinted clean-up procedure. The method was based on two steps. In the first one, conventional solvent extraction was replaced by VMAE for extraction of auxins from plant tissues. This step provided efficient extraction of 3-indole acetic acid (IAA) from plant with dramatically decreased extraction time, furthermore prevented auxins from degradation by creating a reduced oxygen environment under vacuum condition. In the second step, the raw extract of VMAE was further subjected to a clean-up procedure by magnetic molecularly imprinted polymer (MIP) beads. Owing to the high molecular recognition ability of the magnetic MIP beads for IAA and 3-indole-butyric acid (IBA), the two target auxins in plants can be selectively enriched and the interfering substance can be eliminated by dealing with a magnetic separation procedure. Both the VMAE and the molecularly imprinted clean-up conditions were investigated. The proposed sample preparation method was coupled with high-performance liquid chromatogram and fluorescence detection for determination of IAA and IBA in peas and rice. The detection limits obtained for IAA and IBA were 0.47 and 1.6 ng/mL and the relative standard deviation were 2.3% and 2.1%, respectively. The IAA contents in pea seeds, pea embryo, pea roots and rice seeds were determined. The recoveries were ranged from 70.0% to 85.6%. The proposed method was also applied to investigate the developmental profiles of IAA concentration in pea seeds and rice seeds during seed germination. PMID:20953778

  20. Efficient sample clean-up and online preconcentration for sensitive determination of melamine in milk samples by capillary electrophoresis with contactless conductivity detection.

    PubMed

    Ji, Yan-ling; Chen, Xiao-wei; Zhang, Zhu-bao; Li, Jing; Xie, Tian-yao

    2014-10-01

    Based on an efficient sample clean-up and field-amplified sample injection online preconcentration technique in capillary electrophoresis with contactless conductivity detection, a new analytical method for the sensitive determination of melamine in milk samples was established. In order to remove the complex matrix interference, which resulted in a serious problem during field-amplified sample injection, liquid-liquid extraction was utilized. As a result, liquid-liquid extraction provides excellent sample clean-up efficiency when ethyl acetate was used as organic extraction by adjusting the pH of the sample solution to 9.5. Both inorganic salts and biological macromolecules are effectively removed by liquid-liquid extraction. The sample clean-up procedure, capillary electrophoresis separation parameters and field-amplified sample injection conditions are discussed in detail. The capillary electrophoresis separation was achieved within 5 min under the following conditions: an uncoated fused-silica capillary, 12 mM HAc + 10 mM NaAc (pH = 4.6) as running buffer, separation voltage of +13 kV, electrokinetic injection of +12 kV × 10 s. Preliminary validation of the method performance with spiked melamine provided recoveries >90%, with limits of detection and quantification of 0.015 and 0.050 mg/kg, respectively. The relative standard deviations of intra- and inter-day were below 6%. This newly developed method is sensitive and cost effective, therefore, suitable for screening of melamine contamination in milk products. PMID:25082754

  1. Cleaning up the Legacy of the Cold War: Plutonium Oxides and the Role of Synchrotron Radiation Research

    SciTech Connect

    Clark, David Lewis

    2015-01-21

    The deceptively simple binary formula of AnO2 belies an incredibly complex structural nature, and propensity to form mixed-valent, nonstoichiometric phases of composition AnO2±x. For plutonium, the very formation of PuO2+x has challenged a long-established dogma, and raised fundamental questions for long-term storage and environmental migration. This presentation covers two aspects of Los Alamos synchrotron radiation studies of plutonium oxides: (1) the structural chemistry of laboratory-prepared AnO2+x systems (An = U, Pu; 0 ≤ x ≤ 0.25) determined through a combination of x-ray absorption fine structure spectroscopy (XAFS) and x-ray scattering of laboratory prepared samples; and (2) the application of synchrotron radiation towards the decontamination and decommissioning of the Rocky Flats Environmental Technology Site. Making the case for particle transport mechanisms as the basis of plutonium and americium mobility, rather than aqueous sorption-desorption processes, established a successful scientific basis for the dominance of physical transport processes by wind and water. The scientific basis was successful because it was in agreement with general theory on insolubility of PuO2 in oxidation state IV, results of ultrafiltration analyses of field water/sediment samples, XAFS analyses of soil, sediment, and concrete samples, and was also in general agreement with on-site monitoring data. This understanding allowed Site contractors to rapidly move to application of soil erosion and sediment transport models as the means of predicting plutonium and americium transport, which led to design and application of site-wide soil erosion control technology to help control downstream concentrations of plutonium and americium in streamflow.

  2. Diffuse-Reflectance Mid-Infrared Spectral Properties of Soils under Alternative Crop Rotations in a Semiarid Climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An Alternative Crop Rotations (ACR) experiment was designed to compare the traditional wheat-fallow rotation with more intensive no-till rotations in the Central Great Plains. In order to ascertain the effect of the different agronomic managements on soil quality, we carried out mid-infrared (MidIR)...

  3. Native Kenyan plants as possible alternatives to methyl bromide in soil fumigation.

    PubMed

    Rugutt, J K; Ngigi, A N; Rugutt, K J; Ndalut, P K

    2006-09-01

    Methyl bromide (CH3Br) is a biocidal fumigant used widely in crop production and commodity preservation worldwide. CH3Br escapes to the stratosphere and releases bromine atom (Br), which contributes to significant destruction of the ozone (O3). It is therefore necessary to explore alternatives to CH3Br that are environmentally safe and suitable for resource-poor African farmers. We present here the results of a study on the inhibitory activity of crude extracts from Kenyan medicinal plants against three soil pathogens, Fusarium oxysporum, Alternaria passiflorae, and Aspergillus niger. Crude organic extracts of Warburgia ugandensis Sprague, Azadirachta indica A. Juss, Tagetes minuta and Urtica massaica were active against all soil pathogens, while those from U. massaica were not. Chromatographic purification of the crude extract of W. ugandensis provided two pure compounds, muzigadial (1) and muzigadiolide (5). The minimum inhibitory concentration (MIC value) for muzigadial (1) ranged from 5 to 100mug/ml. Muzigadiolide (5) was not active. Greenhouse tests of W. ugandensis extracts against F. oxysporium pathogen showed the most effective inhibitory concentration to be at least 5 mg/ml. Quantitative structure-activity relationship (QSAR) models were used to rationalize the variation in biological activities of muzigadial (1), warburganal (2), polygodial (3), ugandensidial (4), muzigadiolide (5), azadirachtin (6), and CH3Br. The models were based on several molecular descriptors including LogP, van der Waals surface area (VDW(A)), van der Waals volume (VDW(v)), dipole moment, total energy, polarizability, and differences between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO gap). PMID:16920513

  4. Determination of triazine herbicides in seaweeds: development of a sample preparation method based on Matrix Solid Phase Dispersion and Solid Phase Extraction Clean-up.

    PubMed

    Rodríguez-González, N; González-Castro, M J; Beceiro-González, E; Muniategui-Lorenzo, S; Prada-Rodríguez, D

    2014-04-01

    A method using dual process columns of Matrix Solid Phase Dispersion (MSPD) and Solid Phase Extraction (SPE) has been developed for extracting and cleaning-up of nine triazine herbicides (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine and terbutryn) in seaweed samples. Under optimized conditions, samples were blended with 2g of octasilyl-derivatized silica (C8) and transferred into an SPE cartridge containing ENVI-Carb II/PSA (0.5/0.5 g) as a clean up co-sorbent. Then the dispersed sample was washed with 10 mL of n-hexane and triazines were eluted with 20 mL ethyl acetate and 5 mL acetonitrile. Finally the extract was concentrated to dryness, re-constituted with 1 mL methanol:water (1:1) and injected into the HPLC-DAD system. The linearity of the calibration curves was excellent in matrix matched standards, and yielded the coefficients of determination>0.995 for all the target analytes. The recoveries ranged from 75% to 100% with relative standard deviations lower than 7%. The achieved LOQs (<10 µg kg(-1)) for all triazines under study permits to ensure proper determination at the maximum allowed residue levels set in the European Union Legislation. Samples of three seaweeds were subjected to the procedure proving the suitability of MSPD method for the analysis of triazines in different seaweeds samples. PMID:24607126

  5. Determination of pesticides in edible oils by liquid chromatography-tandem mass spectrometry employing new generation materials for dispersive solid phase extraction clean-up.

    PubMed

    Dias, Jonatan V; Cutillas, Victor; Lozano, Ana; Pizzutti, Ionara R; Fernández-Alba, Amadeo R

    2016-09-01

    The goal of this work was to evaluate the efficiency of several sorbents on removal fats from edible oils (olive, soya and sunflower) during the clean-up step for posterior determination of 165 pesticides by UHPLC-QqQ-MS/MS system. The extraction procedure employed in this work was the citrate version of QuEChERS method followed by a step of freezing out with dry ice and clean-up evaluation using i) PSA with magnesium sulfate (d-SPE); ii) magnesium sulfate and Z-sep sorbent (d-SPE); iii) Z-sep (column SPE) and iv) Agilent Bond Elut QuEChERS Enhanced Matrix Removal-Lipid (EMR-Lipid). After evaluation of the recovery results at 10, 20 and 50μgkg(-1), the EMR-Lipid showed important advantages comparing to the other sorbents evaluated, such as better recovery rates and RSD%. The method was validated at the three concentrations described above. Analytical curves linearity was evaluated by spiking blank oil samples at 10, 20, 50, 100 and 500μgkg(-1). The method demonstrated good recoveries values between the acceptable range of 70-120% and RSD%<20 for most of evaluated pesticides. In order to evaluate the performance of the method, this same procedure was employed to other oils such as soya and sunflower with very good results. PMID:27507727

  6. Determination of eight sulfonamides in bovine kidney by liquid chromatography/tandem mass spectrometry with on-line extraction and sample clean-up.

    PubMed

    Van Eeckhout, N; Perez, J C; Van Peteghem, C

    2000-01-01

    A sensitive, high performance liquid chromatography/tandem mass spectrometric (i.e. mass spectrometry/mass spectrometry; LC/MS/MS) method with on-line extraction and sample clean-up for the screening and confirmation of residues of sulfonamides in kidney is described. The sulfonamides are extracted from homogenized kidney with methanol. After centrifugation of the extract, an aliquot of the extract is directly injected on the LC/MS/MS system with further extraction and clean-up of the sample on-line. Detection of the analytes was achieved by positive electrospray ionization (ESI) followed by multiple reaction monitoring. For each sulfonamide the collisional decomposition of the protonated molecule to a common, abundant fragment ion was monitored. The method has been validated for sulfadimethoxine, sulfaquinoxaline, sulfamethazine, sulfamerazine, sulfathiazole, sulfamethoxazole, sulfadiazine and sulfapyridine. Calibration curves resulting from spiked blank kidney samples at the 10-200 microg/kg level showed good linear correlation. At the level of 50, 100 and 200 microg/kg both within- and between-day precision, as measured by relative standard deviation (RSD), were less than 16%. The limits of detection (LODs) ranged from 5 to 13.5 microg/kg. The recoveries ranged from 78 to 82%. The procedure provides a rapid, reliable and sensitive method for the determination of residues of sulfonamides in bovine kidney. The advantage of this method over existing methods is its decreased sample preparation and analysis time, which makes the method more suitable for routine analysis. PMID:11114046

  7. [Simultaneous determination of zeranols and chloramphenicol in foodstuffs of animal origin by combination immunoaffinity column clean-up and liquid chromatography-tandem mass spectrometry].

    PubMed

    Wang, Qing; Wang, Guomin; Xi, Cunxian; Li, Xianliang; Chen, Dongdong; Tang, Bobin; Zhang, Lei; Zhao, Hua

    2014-06-01

    A combination immunoaffinity column (IAC-CZ) clean-up and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method was successfully developed for zearalenol, beta-zearalenol and zearalenone) and chloramphenicol (CAP) in foodstuffs of animal origin. The samples (fish, liver, milk and honey) were enzymatically digested by beta-glucuronidase/sulfatase for about 16 h and then extracted with ether. The extracts were evaporated to dryness and then the residues were dissolved by 1.0 mL of 50% acetonitrile solution. After filtered and diluted with PBS buffer, the reconstituted solution were cleaned-up with a IAC-CZ and then analyzed by LC-MS/MS in multiple reaction monitoring (MRM) mode. The chromatographic separation was performed on a Shimadzu Shim-pack VP-ODS column with gradient elution by acetonitrile and 2 mmol/L ammonium acetate solution. The detection was carried out by electrospray negative ionization mass spectrometry in MRM mode. The proposed method was validated by the limit of detection (0.04-0.10 microg/kg), linearity (R2 > or = 0.999 0), average recoveries (70.9%-95.6%) and precisions (2.0% - 11.8%). The developed method is reliable, sensitive and has good applicability. The combination immunoaffinity column was proved to be an effective pretreatment technique to decrease the matrix effect, and it met the requirements of residue analysis of co-occurring zeranols and chloramphenicol. PMID:25269264

  8. Determination of Aflatoxin M1 in Milk Powder by Ultrasonic-Assisted Extraction and Dispersive Solid-Phase Clean-up.

    PubMed

    Manoochehri, Mahboobeh; Asgharinezhad, Ali Akbar; Safaei, Mahdi

    2015-07-01

    This work describes the application of ultrasound-assisted dispersive solid-phase extraction (UA-DSPE) as a sample preparation approach for aflatoxin M1 (AFM1) and also its subsequent determination by HPLC-fluorescence detection. A Box-Behnken design in combination with response surface methodology was implemented to determine the variables affecting the extraction procedure. The effects of different variables, including type and quantity of clean-up phase, ultrasonication time, ultrasonication temperature, nature and volume of the leaching solvent, were investigated in the optimization study. Primary secondary amine (PSA) and acetonitrile were selected as the clean-up phase and the leaching solvent, respectively. The obtained optimized values were 30 mg of PSA, 10 min ultrasonication time, 32°C ultrasonication temperature and 10 mL of acetonitrile. Under the optimal conditions, the limit of detection and limit of quantification were 0.0012 and 0.0045 µg kg(-1), respectively. The recoveries of the UA-DSPE procedure ranged from 80 to 92%, with relative standard deviations lower than 10% in all cases. Eventually, this method was successfully applied to the extraction of AFM1 in milk powder samples. PMID:25378372

  9. The effect of vertically resolved soil biogeochemistry and alternate soil C and N models on C dynamics of CLM4

    NASA Astrophysics Data System (ADS)

    Koven, C. D.; Riley, W. J.; Subin, Z. M.; Tang, J. Y.; Torn, M. S.; Collins, W. D.; Bonan, G. B.; Lawrence, D. M.; Swenson, S. C.

    2013-11-01

    Soils are a crucial component of the Earth system; they comprise a large portion of terrestrial carbon stocks, mediate the supply and demand of nutrients, and influence the overall response of terrestrial ecosystems to perturbations. In this paper, we develop a new soil biogeochemistry model for the Community Land Model, version 4 (CLM4). The new model includes a vertical dimension to carbon (C) and nitrogen (N) pools and transformations, a more realistic treatment of mineral N pools, flexible treatment of the dynamics of decomposing carbon, and a radiocarbon (14C) tracer. We describe the model structure, compare it with site-level and global observations, and discuss the overall effect of the revised soil model on Community Land Model (CLM) carbon dynamics. Site-level comparisons to radiocarbon and bulk soil C observations support the idea that soil C turnover is reduced at depth beyond what is expected from environmental controls for temperature, moisture, and oxygen that are considered in the model. In better agreement with observations, the revised soil model predicts substantially more and older soil C, particularly at high latitudes, where it resolves a permafrost soil C pool. In addition, the 20th century-C dynamics of the model are more realistic than those of the baseline model, with more terrestrial C uptake over the 20th century due to reduced N downregulation and longer turnover times for decomposing C.

  10. Preliminary screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil, Rocky Mountain Arsenal

    SciTech Connect

    Shem, L.M.; Rosenblatt, D.H.; Smits, M.P.; Wilkey, P.L.; Ballou, S.W.

    1995-12-01

    In support of the U.S. Army`s efforts to determine the best technologies for remediation of soils, water, and structures contaminated with pesticides and chemical agents, Argonne National Laboratory has reviewed technologies for treating soils contaminated with mustard, lewisite, sarin, o-ethyl s-(2- (diisopropylamino)ethyl)methyl-phosphonothioate (VX), and their breakdown products. This report focuses on assessing alternatives to incineration for dealing with these contaminants. For each technology, a brief description is provided, its suitability and constraints on its use are identified, and its overall applicability for treating the agents of concern is summarized. Technologies that merit further investigation are identified.

  11. ENGINEERING BULLETIN: SEPARATION/CONCENTRATION TECHNOLOGY ALTERNATIVES FOR THE REMEDIATION OF PESTICIDE-CONTAMINATED SOIL

    EPA Science Inventory

    Pesticide contamination includes a wide variety of compounds and may result from manufacturing improper storage, handling, disposal; or agricultural processes. It can occur in soil and can lead to secondary contamination of groundwater. Remediation of pesticide-contaminated soils...

  12. Bioremediation: An effective remedial alternative for petroleum hydrocarbon-contaminated soil

    SciTech Connect

    Autry, A.R.; Ellis, G.M. )

    1992-11-01

    Bioremediation technologies applied to contaminated soil usually mitigate environmental rate-limiting factors so that biodegradation rates are maximized for any given compound. A newer approach to soil bioremediation mitigates these environmental rate-limiting factors simultaneously, initially allowing biodegradation to proceed at a maximal rate without the need for additional action. This technology involves intensive mixing of contaminated soil in a ribbon blender, introduction of a protein-based, surfactant-containing nutrient additive to the soil while in the mixer, physical entrainment of oxygen-containing air into the soil, discharge of the mixed soil from the mixer, and placement of the mixed soil in curing piles, for curing, during which time biodegradation can occur. No additional treatment actions (e.g., tillage, fertilizer or water applications) are typically required. The remediation, using this approach, of a former distribution facility which possessed soil contaminated with gasoline, is summarized. 22 refs., 6 figs.

  13. Anaerobic Soil Disinfestation (ASD) and Steam As Alternatives For Parasitic Nematode Control In Florida Floriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anaerobic soil disinfestation (ASD) and steam are being investigated for controlling a broad spectrum of pests, including parasitic nematodes and weeds. ASD is a biologically-based method that combines organic amendments and solar heat with water saturated soil to create oxygen-depleted soil co...

  14. Active solarization as a nonchemical alternative to soil fumigation for controlling pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deterioration of soil, water, and air resources by soil fumigants represents a serious threat to agricultural production in semiarid regions due to their high volatility and high emission rates. New pest control methods are needed that do not rely on fumigant chemicals. Soil heating via solarization...

  15. Planar solid phase extraction clean-up and microliter-flow injection analysis-time-of-flight mass spectrometry for multi-residue screening of pesticides in food.

    PubMed

    Oellig, Claudia; Schwack, Wolfgang

    2014-07-18

    For multi-residue analysis of pesticides in food, a sufficient clean-up is essential for avoiding matrix effects in liquid and gas chromatography (LC and GC) analysis coupled to mass spectrometry (MS). In the last two years, high-throughput planar solid phase extraction (HTpSPE) was established as a new clean-up concept for pesticide residue analysis in fruits and vegetables (C. Oellig, W. Schwack, 2011) and tea (C. Oellig, W. Schwack, 2012). HTpSPE results in matrix-free extracts almost free of interferences and matrix effects. In this study, a time-of-flight mass spectrometer (TOFMS) was applied to directly analyze HTpSPE extracts for pesticide residues. This HTpSPE-microliter-flow injection analysis (μL-FIA)-TOFMS approach detects all pesticides at once in a single mass spectrum, without a liquid chromatographic separation step. Complete sample information was obtained after the injection of the cleaned extract within a single peak. Recovery studies for seven representative pesticides in four different matrices (apples, red grapes, cucumbers, tomatoes) provided mean recoveries of 86-116% with relative standard deviations of 1.3-10% (n=5) using the mass signal intensities under the entire sample peak. Comparing the mass spectra of sample peaks from spiked extracts and solvent standards indicated the efficiency of HTpSPE clean-up. A pesticide database search detected all spiked pesticides with a low incidence of false-positives. HTpSPE of one sample required a few minutes, and numerous samples could be cleaned in parallel at minimal cost with low sample and solvent consumption. The μL-FIA-TOFMS screening then needed an additional 6min per sample. The novel screening approach was successfully applied to QuEChERS extracts of several real samples, and the pesticides identified by HTpSPE-μL-FIA-TOFMS were identical to the pesticides detected by common target LC-MS/MS analyses. The high degree of concordantly identified pesticides by the new developed HTp

  16. Dispersive solid-phase extraction as a simplified clean-up technique for biological sample extracts. Determination of polybrominated diphenyl ethers by gas chromatography-tandem mass spectrometry.

    PubMed

    Fontana, Ariel R; Camargo, Alejandra; Martinez, Luis D; Altamirano, Jorgelina C

    2011-05-01

    Dispersive solid-phase extraction (DSPE) is proposed for the first time as a simplified, fast and low cost clean-up technique of biological sample extracts for polybrominated diphenyl ethers (PBDEs) determination. The combination of a traditional extraction technique, such as ultrasound-assisted leaching (USAL) with DSPE was successfully applied for sample preparation prior to gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis. The analytes were first extracted from 1g homogenized sample in n-hexane:dichloromethane (8:2) by applying USAL technique and further cleaned-up using DSPE with 0.20 g C(18)-silica as sorbent material. Different solvent mixtures, sorbent type and amount, and lipid digestion procedures were evaluated in terms of clean-up and extraction efficiency. Under optimum conditions, the method detection limits (MDLs) for PBDEs, calculated as three times the signal-to-noise ratio (S/N) were within the range 9-44 pg g(-1) wet weight. The calibration graphs were linear within the concentration range of 53-500,000 pg g(-1), 66-500,000 pg g(-1), 89-500,000 pg g(-1) and 151-500,000 pg g(-1) for BDE-47, BDE-100, BDE-99 and BDE-153, respectively; and the coefficient of determination (r(2)) exceeded 0.9992 for all analytes. The proposed methodology was compared with a reference solid-phase extraction technique. The applicability of the methodology for the screening of PBDEs has been demonstrated by analyzing spiked and real samples of biological nature (fish, egg and chicken) with different lipid content as well as reference material (WELL-WMF-01). Recovery values ranged between 75% and 114% and the measured concentrations in certified material showed a reasonable agreement with the certified ones. BDE-47, BDE-100 and BDE-99 were quantified in three of the seven analyzed samples and the concentrations ranged between 91 and 140 pg g(-1). In addition, this work is the first description of PBDEs detected in fish of Argentinean environment. PMID

  17. Alternative poultry litter storage for improved transportation and use as a soil amendment.

    PubMed

    Penn, Chad J; Vitale, Jeffery; Fine, Scott; Payne, Joshua; Warren, Jason G; Zhang, Hailin; Eastman, Margaret; Herron, Sheri L

    2011-01-01

    Transportation of poultry litter out of nutrient limited watersheds such as the Illinois River basin (eastern Oklahoma) is a logical solution for minimizing phosphorus (P) losses from soils to surface waters. Transportation costs are basedon mass of load and distance transported. This study investigated an alternative litter storage technique designed to promote carbon (C) degradation, thereby concentrating nutrients for the purpose of decreasing transportation costs through decreased mass. Poultry litter was stored in 0.90-Mg conical piles under semipermeable tarps and adjusted to 40% moisture content, tested with and without addition of alum (aluminum sulfate). additional study was conducted using 3.6-Mg piles under the same conditions, except tested with and without use of aeration pipes. Samples were analyzed before and after (8 wk) storage. Litter mass degradation (i.e., loss in mass due to organic matter decomposition) was estimated on the basis of changes in litter total P contents. Additional characterization included pH, total nutrients, moisture content, total C, and degree of humification. Litter storage significantly decreased litter mass (16 to 27%), concentrated nutrients such as P and potassium (K) and increased proportion of fulvic and humic acids. The addition of aeration pipes increased mass degradationrelative to piles without aeration pipes. Nitrogen volatilization losses were minimized with alum additions. Increases in P and K concentrations resulted in greater monetary value per unit mass compared with fresh litter. Such increases translate to increased litter shipping distance and cost savings of $17.2 million over 25 yr for litter movement out of eastern Oklahoma. PMID:21488512

  18. Improvement of chemical analysis of antibiotics. IX. A simple method for residual tetracyclines analysis in honey using a tandem cartridge clean-up system.

    PubMed

    Oka, H; Ikai, Y; Kawamura, N; Uno, K; Yamada, M; Harada, K; Uchiyama, M; Asukabe, H; Mori, Y; Suzuki, M

    1987-03-13

    A simple, rapid and precise analytical method for the residual tetracyclines in honey has been established using a tandem cartridge clean-up system (prepacked reversed-phase and ion-exchange cartridges) followed by high-performance liquid chromatography. The recoveries of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from honey spiked at a level of 1.0 ppm are 87.1, 85.3, 98.0 and 99.0%, respectively, with coefficients of variation of 1.1-3.9%. The detection limits in honey are 0.02 ppm for OTC and TC, and 0.05 ppm for CTC and DC, respectively. The time required for the analysis of four samples is only 1 h. PMID:3106387

  19. Use of gel permeation chromatography for clean-up in the analysis of coccidiostats in eggs by liquid chromatography-tandem mass spectrometry.

    PubMed

    Chico, J; Rúbies, A; Centrich, F; Companyó, R; Prat, M D; Granados, M

    2013-05-01

    An analytical method for determination and confirmation of nine coccidiostatics in eggs is reported. Ethyl acetate is used as extraction solvent, with satisfactory results, and simple automated clean-up is based on gel-permeation chromatography (GPC) . The target compounds are then analysed by liquid chromatography-electrospray ionization-tandem mass spectrometry. The method was validated in-house in accordance with Commission Decision 2002/657/EC. Trueness and precision were determined at four concentrations, and the mean errors obtained were <10 %, with relative standard deviations ranging from 3 to 18 %. For three non-authorized coccidiostatics (clopidol, ethopabate, and ronizadole), decision limit and detection capability were in the ranges 0.12-0.16 and 0.18-0.23 μg kg(-1), respectively. The results obtained prove the suitability of this new analytical method for routine monitoring of these substances in eggs. PMID:23535744

  20. Rapid determination of 88 veterinary drug residues in milk using automated TurborFlow online clean-up mode coupled to liquid chromatography-tandem mass spectrometry.

    PubMed

    Zhu, Wei-xia; Yang, Ji-zhou; Wang, Zhao-xing; Wang, Cai-juan; Liu, Ya-feng; Zhang, Li

    2016-02-01

    A novel method based on TurborFlow online solid phase extraction (SPE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been established for simultaneous screening and confirmation of 88 wide-range veterinary drugs belonging to eight families (20 sulfonamides, 7 macrolides, 15 quinolones, 8 penicillins, 13 benzimidazoles, 4 tetracyclines, 2 sedatives, and 19 hormones) in milk. The preparation method consists of sample dilution and ultrasonic extraction, followed by an automated turbulent flow cyclone chromatography sample clean-up system. The detection was achieved in selected reaction monitoring mode (SRM). The total run time was within 39 min, including automated extraction, analytical chromatography and re-equilibration of the turboflow system. The optimization of different experimental parameters including extraction, purification, separation, and detection were evaluated separately in this study. The developed method was validated and good performing characteristics were obtained. The linear regression coefficients (R(2)) of matrix-match calibration standard curves established for quantification were higher than 0.9930. The limits of detection (LOD) were in the range of 0.2-2.0 μg/kg given by signal-noise ratio ≥3 (S/N) and the limits of quantification (LOQ, S/N≥10) ranged between 0.5 μg/kg and 10 μg/kg. Average recoveries of spiked target compounds with different levels were between 63.1% and 117.4%, with percentage relative standard deviations (RSD) in the range of 3.3-17.6%. The results indicated that the developed method has great potential for the routine laboratory analysis of large numbers of samples on measuring different classes of compounds. In comparison to traditional procedures, the automated sample clean-up ensures rapid, effective, sensitive analyses of veterinary drugs in milk. PMID:26653466

  1. Simultaneous determination of four aflatoxins and ochratoxin A in ginger and related products by HPLC with fluorescence detection after immunoaffinity column clean-up and postcolumn photochemical derivatization.

    PubMed

    Wen, Jing; Kong, Weijun; Wang, Jian; Yang, Meihua

    2013-12-01

    Ginger, a widely used spice and traditional Chinese medicine, is prone to be contaminated by mycotoxins. A simple, sensitive, and reproducible method based on immunoaffinity column clean-up coupled with HPLC and on-line postcolumn photochemical derivatization with fluorescence detection was developed for the simultaneous determination of aflatoxins (AFs) B1 , B2 , G1 , G2 , and ochratoxin A (OTA) in 25 batches of gingers and related products marketed in China for the first time. The samples were first extracted by ultrasonication with methanol/water (80:20, v/v) and then cleaned up with immunoaffinity columns for analysis. Under the optimized conditions, the LODs and LOQs for the five mycotoxins were 0.03-0.3 and 0.1-0.9 μg/kg, respectively. The average recoveries ranged from 81.3-100.8% for AFs and from 88.6-99.5% for OTA at three spiking levels. Good linearity was observed for the analytes with correlation coefficients all >0.9995. All moldy gingers were contaminated with at least one kind of the five investigated mycotoxins, while none of them were found in normal gingers. Ginger powder samples were contaminated slightly with the contamination levels below the LOQs, while ginger tea bags were mainly contaminated by OTA at 1.05-1.19 μg/kg and ginger black tea bags were mainly contaminated by AFs at 3.37-5.76 μg/kg. All the contamination levels were below the legally allowable limits. PMID:24115567

  2. Determination of endocrine disrupting compounds in fish liver, brain, and muscle using focused ultrasound solid-liquid extraction and dispersive solid phase extraction as clean-up strategy.

    PubMed

    Ros, Oihana; Vallejo, Asier; Olivares, Maitane; Etxebarria, Nestor; Prieto, Ailette

    2016-08-01

    This study describes a new method for the simultaneous extraction of several endocrine disrupting compounds, including alkylphenols (APs), estrogen, bisphenol-A (BPA) and one phthalate metabolite (mono-2-ethylhexyl ester, MEHP) in fish liver, brain, and muscle. Parameters affecting the extraction (extraction solvent and temperature) and the clean-up (dispersive phase nature and amount) steps were evaluated. The extraction was performed by means of focused ultrasound solid-liquid extraction (FUSLE) using 10 mL of n-hexane:acetone (50:50, v/v) for 5 min at ~0 °C, and the clean-up was done by means of dispersive solid phase extraction (dSPE) using 100 mg of ENVI-CARB and 100 mg of MgSO4 for the cleaning of brain and muscle extracts together with 100 mg of PSA in the case of liver extracts. Good apparent recoveries were obtained in the case of liver (62-132 %), brain (66-120 %), and muscle (74-129 %), relative standard deviation (RSD%) was always below 26 %, and the method detection limits (MDLs) were at low ng/g level. The developed method was applied to fish captured in Urdaibai estuary (Bay of Biscay) in December 2015, and the concentrations obtained were in the range MDL-1115 ng/g in brain, MDL-962 ng/g in muscle, and MDL-672 ng/g in liver. In general, the highest concentrations were measured in liver, followed by brain and muscle. In addition, diethylstilbestrol was only detected in fish brain. Graphical Abstract MS method scheme for the/MS method scheme for the determination of EDCs in fish liver, brain and muscle. PMID:27342793

  3. Molecularly imprinted polymers applied to the clean-up of zearalenone and alpha-zearalenol from cereal and swine feed sample extracts.

    PubMed

    Urraca, Javier L; Marazuela, María Dolores; Moreno-Bondi, María C

    2006-08-01

    A molecularly imprinted polymer prepared using 1-allylpiperazine (1-ALPP) as the functional monomer, trimethyltrimethacrylate (TRIM) as the crosslinker and the zearalenone (ZON)-mimicking template cyclododecanyl-2,4-dihydroxybenzoate (CDHB) has been applied to the clean-up and preconcentration of this mycotoxin (zearalenone) and a related metabolite, alpha-zearalenol (alpha-ZOL), from cereal and swine feed sample extracts. The extraction of ZON and alpha-ZOL from the food samples was accomplished using pressurized liquid extraction (PLE) with MeOH/ACN (50:50, v/v) as the extraction solvent, at 50 degrees C and 1500 psi. The extracted samples were cleaned up and preconcentrated through the MIP cartridge and analyzed using HPLC with fluorescence detection (lambda (exc)=271/ lambda (em)=452 nm). The stationary phase was a polar endcapped C18 column, and ACN/MeOH/water 10/55/35 (v/v/v, 15 mM ammonium acetate) at a flow rate of 1.0 mL min(-1) was used as the mobile phase. The method was applied to the analysis of ZON and alpha-ZOL in wheat, corn, barley, rye, rice and swine feed samples fortified with 50, 100 and 400 ng g(-1) of both mycotoxins, and it gave recoveries of between 85 and 97% (RSD 2.1-6.7%, n=3) and 87-97% (RSD 2.3-5.6%, n=3) for alpha-ZOL and ZON, respectively. The method was validated using a corn reference material for ZON. PMID:16628404

  4. Simultaneous analysis of organochlorinated pesticides (OCPs) and polychlorinated biphenyls (PCBs) from marine samples using automated pressurized liquid extraction (PLE) and Power Prep™ clean-up.

    PubMed

    Helaleh, Murad I H; Al-Rashdan, Amal; Ibtisam, A

    2012-05-30

    An automated pressurized liquid extraction (PLE) method followed by Power Prep™ clean-up was developed for organochlorinated pesticide (OCP) and polychlorinated biphenyl (PCB) analysis in environmental marine samples of fish, squid, bivalves, shells, octopus and shrimp. OCPs and PCBs were simultaneously determined in a single chromatographic run using gas chromatography-mass spectrometry-negative chemical ionization (GC-MS-NCI). About 5 g of each biological marine sample was mixed with anhydrous sodium sulphate and placed in the extraction cell of the PLE system. PLE is controlled by means of a PC using DMS 6000 software. Purification of the extract was accomplished using automated Power Prep™ clean-up with a pre-packed disposable silica column (6 g) supplied by Fluid Management Systems (FMS). All OCPs and PCBs were eluted from the silica column using two types of solvent: 80 mL of hexane and a 50 mL mixture of hexane and dichloromethane (1:1). A wide variety of fish and shellfish were collected from the fish market and analyzed using this method. The total PCB concentrations were 2.53, 0.25, 0.24, 0.24, 0.17 and 1.38 ng g(-1) (w/w) for fish, squid, bivalves, shells, octopus and shrimp, respectively, and the corresponding total OCP concentrations were 30.47, 2.86, 0.92, 10.72, 5.13 and 18.39 ng g(-1) (w/w). Lipids were removed using an SX-3 Bio-Beads gel permeation chromatography (GPC) column. Analytical criteria such as recovery, reproducibility and repeatability were evaluated through a range of biological matrices. PMID:22608412

  5. Exhaust gas clean up process

    SciTech Connect

    Walker, R.J.

    1989-04-11

    A method of cleaning an exhaust gas containing particulates, SO/sub 2/ and NO/sub x/ includes prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO/sub x/ and SO/sub 2/. and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO/sub x/ is removed as N/sub 2/ or nitrogen-sulfonate ions and the oxides of sulfur are removed as a valuable sulfate salt.

  6. Exhaust gas clean up process

    DOEpatents

    Walker, R.J.

    1988-06-16

    A method of cleaning an exhaust gas containing particulates, SO/sub 2/ and NO/sub x/ is described. The method involves prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO/sub x/ and SO/sub 2/, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO/sub x/ is removed as N/sub 2/ gas or nitrogen sulfonate ions and the oxides of sulfur are removed as a valuable sulfate salt. 4 figs.

  7. Metalworkers clean up their waste

    SciTech Connect

    Valenti, M.

    1994-10-01

    This article describes how using methods such as chemical precipitation, filtration, and ion exchange, metal parts manufacturers are reducing the pollutants in their wastewater so it can be reused or safely discharged. Metalworking manufacturer are recovering useful materials, lowering their disposal costs, and reducing pollution by treating their wastewater with methods such as chemical precipitation and ion exchange so that it can be reused or safely discharged. They are also reducing wastes by recycling metalworking coolants. The major wastewater treatment technologies identified by the Environmental Protection Agency are chemical precipitation, or adding flocculants to bind waste particles together; membrane ultrafiltration and reverse osmosis, in which waste is trapped when the water passes through a membrane; and ion exchange, in which specially formulated resins capture dissolved metal salts. Other treatment techniques cited by Elwood Forsht, chief of the chemicals and metals branch at the EPA, include electrowinning, which uses electrolysis to concentrate metallic ions in wastewater, and coolant recycling, a method that removes metal particles by centrifugal force and kills bacteria by pasteurization. Many metalworking operations create wastewater, including drilling, welding, soldering, surface finishing, electroplating, acid treatment, anodizing, assembly, and machining. Companies use wastewater treatment technologies to recycle their wastewater or clean it so that it meets EPA standards and can be discharged into a municipal waste system, thus avoiding high disposal costs.

  8. Exhaust gas clean up process

    DOEpatents

    Walker, Richard J.

    1989-01-01

    A method of cleaning an exhaust gas containing particulates, SO.sub.2 and NO.sub.x includes prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO.sub.x and SO.sub.2, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO.sub.x is removed as N.sub.2 or nitrogen-sulfonate ions and the oxides of sulfur are removed as a vaulable sulfate salt.

  9. Enhanced thermal conduction -- An alternative solution for removing a broad range of hydrocarbons from contaminated soils

    SciTech Connect

    Bova, J.C.

    1999-07-01

    This paper presents an overview of Enhanced Thermal Conduction (ETC), an ex-situ soil remediation process. A review of a practical demonstration of this process which was conducted by Woodward-Clyde Consultants to determine the capability of the technology for remediating soils from gasworks sites that have been contaminated with petroleum hydrocarbons, polynuclear hydrocarbons (PAHs) and cyanide is also presented in this paper. Projections for using this process to treat soils contaminated with other hazardous materials such as TCE PCE and PCB's are discussed as well.

  10. Organic farming and cover crops as an alternative to mineral fertilizers to improve soil physical properties

    NASA Astrophysics Data System (ADS)

    Sánchez de Cima, Diego; Luik, Anne; Reintam, Endla

    2015-10-01

    For testing how cover crops and different fertilization managements affect the soil physical properties in a plough based tillage system, a five-year crop rotation experiment (field pea, white potato, common barley undersown with red clover, red clover, and winter wheat) was set. The rotation was managed under four different farming systems: two conventional: with and without mineral fertilizers and two organic, both with winter cover crops (later ploughed and used as green manure) and one where cattle manure was added yearly. The measurements conducted were penetration resistance, soil water content, porosity, water permeability, and organic carbon. Yearly variations were linked to the number of tillage operations, and a cumulative effect of soil organic carbon in the soil as a result of the different fertilization amendments, organic or mineral. All the systems showed similar tendencies along the three years of study and differences were only found between the control and the other systems. Mineral fertilizers enhanced the overall physical soil conditions due to the higher yield in the system. In the organic systems, cover crops and cattle manure did not have a significant effect on soil physical properties in comparison with the conventional ones, which were kept bare during the winter period. The extra organic matter boosted the positive effect of crop rotation, but the higher number of tillage operations in both organic systems counteracted this effect to a greater or lesser extent.