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2.
ScientificWorldJournal ; 9: 536-8, 2009 Jul 01.
Article in English | MEDLINE | ID: mdl-19578710

ABSTRACT

Modern scientific endeavour is increasingly delivered within an interdisciplinary framework. Analytical environmental chemistry is a long-standing example of an interdisciplinary approach to scientific research where value is added by the close cooperation of different disciplines. This editorial piece discusses the rise of environmental analytical chemistry as an interdisciplinary activity and outlines the scope of the Analytical Chemistry and the Environmental Chemistry domains of TheScientificWorldJOURNAL (TSWJ), and the appropriateness of TSWJ's domain format in covering interdisciplinary research. All contributions of new data, methods, case studies, and instrumentation, or new interpretations and developments of existing data, case studies, methods, and instrumentation, relating to analytical and/or environmental chemistry, to the Analytical and Environmental Chemistry domains, are welcome and will be considered equally.


Subject(s)
Chemistry, Analytic/methods , Environmental Monitoring/methods , Environmental Pollutants/analysis , Research Design , Environmental Pollutants/chemistry , Environmental Pollution/analysis , Environmental Pollution/prevention & control , Research/trends
3.
Environ Sci Technol ; 43(5): 1449-54, 2009 Mar 01.
Article in English | MEDLINE | ID: mdl-19350918

ABSTRACT

The collapse of the World Trade Center Towers on September 11, 2001, sent dust and debris across much of Manhattan and in the surrounding areas. Indoor and outdoor dust samples were collected and characterized by U.S. Geological Survey (USGS) scientists using scanning electron microscopy with energy-dispersive spectrometry (SEM/EDS). From this characterization, the U.S. Environmental Protection Agency and USGS developed a particulate screening method to determine the presence of residual World Trade Center dust in the indoor environment using slag wool as a primary "signature". The method describes a procedure that includes splitting, ashing, and sieving of collected dust From one split, a 10 mg/mL dust/isopropanol suspension was prepared and 10-30 microL aliquots of the suspension placed on an SEM substrate. Analyses were performed using SEM/EDS manual point counting for slag wool fibers. Poisson regression was used to identify some of the sources of uncertainty, which are directly related to the small number of fibers present on each sample stub. Preliminary results indicate that the procedure is promising for screening urban background dust for the presence of WTC dust. Consistent sample preparation of reference materials and samples must be performed by each laboratory wishing to use this method to obtain meaningful and accurate results.


Subject(s)
Air Pollutants/analysis , Chemistry, Analytic/methods , Cities , Dust/analysis , September 11 Terrorist Attacks , Spectrophotometry/methods , Structure Collapse , Microscopy, Electron, Scanning , New York , Reference Standards
4.
Planta Med ; 75(7): 672-82, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19263341

ABSTRACT

Progress in natural product chemistry has always been strongly linked to innovations in analytical technology. The characterisation of metabolites in complex mixtures requires sophisticated techniques, which should provide good sensitivity and selectivity as well as structural information on the constituents of interest. This review outlines the most important chromatographic and spectral techniques which have been introduced in the field of natural products. Although there has been a very rapid evolution of methods over the last 50 years, the introduction of high-throughput screening programmes require even more efficient and sensitive methodologies which yield adequate on-line information for metabolite structure determination.


Subject(s)
Biological Products/chemistry , Chromatography/methods , Spectrum Analysis/methods , Chemistry, Analytic/history , Chemistry, Analytic/methods , Chromatography/history , Herbal Medicine/methods , History, 20th Century , Plants, Medicinal/chemistry
6.
J Environ Radioact ; 100(4): 301-7, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19216013

ABSTRACT

A combination of synchrotron radiation based X-ray microscopic techniques (mu-XRF, mu-XANES, mu-XRD) applied on single depleted uranium (DU) particles and semi-bulk leaching experiments has been employed to link the potential bioavailability of DU particles to site-specific particle characteristics. The oxidation states and crystallographic forms of U in DU particles have been determined for individual particles isolated from selected samples collected at different sites in Kosovo and Kuwait that were contaminated by DU ammunition during the 1999 Balkan conflict and the 1991 Gulf war. Furthermore, small soil or sand samples heavily contaminated with DU particles were subjected to simulated gastrointestinal fluid (0.16 M HCl) extractions. Characteristics of DU particles in Kosovo soils collected in 2000 and in Kuwait soils collected in 2002 varied significantly depending on the release scenario and to some extent on weathering conditions. Oxidized U (+6) was determined in large, fragile and bright yellow DU particles released during fire at a DU ammunition storage facility and crystalline phases such as schoepite (UO(3).2.25H(2)O), dehydrated schoepite (UO(3).0.75H(2)O) and metaschoepite (UO(3).2.0H(2)O) were identified. As expected, these DU particles were rapidly dissolved in 0.16 M HCl (84 +/- 3% extracted after 2 h) indicating a high degree of potential mobility and bioavailability. In contrast, the 2 h extraction of samples contaminated with DU particles originating either from corrosion of unspent DU penetrators or from impacted DU ammunition appeared to be much slower (20-30%) as uranium was less oxidized (+4 to +6). Crystalline phases such as UO(2), UC and metallic U or U-Ti alloy were determined in impacted DU particles from Kosovo and Kuwait, while the UO(2,34) phase, only determined in particles from Kosovo, could reflect a more corrosive environment. Although the results are based on a limited number of DU particles, they indicate that the structure and extractability of DU particles released from similar sources (metallic U penetrators) will depend on the release scenarios (fire, impact) and to some extent environmental conditions. However, most of the DU particles (73-96%) in all investigated samples were dissolved in 0.16 M HCl after one week indicating that a majority of the DU material is bioaccessible.


Subject(s)
Soil/analysis , Uranium/chemistry , Weapons , Biological Availability , Chemistry, Analytic/methods , Electron Probe Microanalysis , Gulf War , Kuwait , Oxidation-Reduction , Solubility , Synchrotrons , Yugoslavia
11.
J Med Toxicol ; 4(2): 93-5, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18570168

ABSTRACT

BACKGROUND: Following the 9/11 terrorist attacks, SET Environmental, Inc., a Chicago-based environmental and hazardous materials management company received a large number of suspicious powders for analysis. METHODS: Samples of powders were submitted to SET for anthrax screening and/or unknown identification (UI). Anthrax screening was performed on-site using a ruggedized analytical pathogen identification device (R.A.P.I.D.) (Idaho Technologies, Salt Lake City, UT). UI was performed at SET headquarters (Wheeling, IL) utilizing a combination of wet chemistry techniques, infrared spectroscopy, and gas chromatography/mass spectroscopy. Turnaround time was approximately 2-3 hours for either anthrax or UI. RESULT: Between October 10, 2001 and October 11, 2002, 161 samples were analyzed. Of these, 57 were for anthrax screening only, 78 were for anthrax and UI, and 26 were for UI only. Sources of suspicious powders included industries (66%), U.S. Postal Service (19%), law enforcement (9%), and municipalities (7%). There were 0/135 anthrax screens that were positive. CONCLUSIONS: There were no positive anthrax screens performed by SET in the Chicago area following the post-9/11 anthrax scare. The only potential biological or chemical warfare agent identified (cyanide) was provided by law enforcement. Rapid anthrax screening and identification of unknown substances at the scene are useful to prevent costly interruption of services and potential referral for medical evaluation.


Subject(s)
Anthrax/prevention & control , Bacillus anthracis/isolation & purification , Bioterrorism , Environmental Monitoring/methods , Powders/analysis , September 11 Terrorist Attacks , Chemistry, Analytic/methods , Gas Chromatography-Mass Spectrometry , Humans , Spectrophotometry, Infrared , Time Factors , United States
13.
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