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1.
Environ Sci Pollut Res Int ; 19(6): 1944-52, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22767292

ABSTRACT

Organochlorinated pesticides were widely applied in Armenia until the 1980s, like in all former Soviet Union republics. Subsequently, the problem of areas contaminated by organochlorinated pesticides emerged. Environmental, waste and food samples at one pesticide burial site (Nubarashen) and three former pesticide storage sites (Jrarat, Echmiadzin and Masis) were taken and analysed on the content of organochlorinated pesticides, polychlorinated dibenzo-p-dioxins and furans and dioxin-like polychlorinated biphenyls. Gradient sampling and diffusivity-based calculations provided information on the contamination release from the hot spots on a local scale. A risk analysis based on samples of locally produced food items characterised the impact of storage sites on the health of nearby residents. All four sites were found to be seriously contaminated. High pesticide levels and soil and air contamination gradients of several orders of magnitude were confirmed outside the fence of the Nubarashen burial site, confirming pesticide release. A storage in Jrarat, which was completely demolished in 1996 and contained numerous damaged bags with pure pesticides until 2011, was found to have polluted surrounding soils by wind dispersion of pesticide powders and air by significant evaporation of lindane and ß-endosulfan during this period. Dichlorodiphenyltrichloroethane-contaminated eggs, sampled from hens roaming freely in the immediate surroundings of the Echmiadzin storage site, revealed a significant health risk for egg consumers above 1E-5. Although small in size and previously almost unknown to the public, storage sites like Echmiadzin, Masis and Jrarat were found to stock considerable amounts of obsolete pesticides and have a significant negative influence on the environment and human health. Multi-stakeholder cooperation proved to be successful in identifying such sites suspected to be significant sources of persistent organic pollutants.


Subject(s)
Environmental Pollution , Pesticides/analysis , Air Pollutants/analysis , Aldrin/analysis , Animals , Armenia , Chickens , Chlordan/analysis , DDT/analysis , Eggs/analysis , Endrin/analysis , Environmental Monitoring , Food Contamination/analysis , Humans , Milk/chemistry , Pesticides/adverse effects , Risk Assessment , Soil Pollutants/analysis
2.
J Hazard Mater ; 207-208: 86-90, 2012 Mar 15.
Article in English | MEDLINE | ID: mdl-21959187

ABSTRACT

This study deals with the treatment of hazardous waste landfill leachate with the help of reverse osmosis. The landfill is located in an abandoned brown coal pit in northern Bohemia. The leachate contained 7.2 g/L of dissolved inorganic salts. Among other contaminants were heavy metals, arsenic, ammonia nitrogen and associated organic pollutants, especially chlorinated compounds. A mobile membrane unit (LAB M30) equipped with a spiral wound element (FILMTEC SW30-4040), with a membrane area equaling 7.4 m2 was used for the pilot plant experiments. All experiments were carried out in batch mode. 94% conversion of the input stream into the permeate was achieved by use of a two-stage arrangement. Removal efficiencies of the monitored contaminants in the feed ranged from 94% for ammonia nitrogen to 99% for the two-valent ions. Removal efficiency for total dissolved solids was 99.3% on average. Due to varying levels of humic acids in the leachate throughout the year, fouling experiments were performed to investigate the separation process under different conditions than those used in the pilot plant. Leachates containing different concentrations of added humic acids were separated using a thin film composite on a propylene membrane. The added humic acids were obtained from samples of contaminated oxihumolite.


Subject(s)
Hazardous Waste , Humic Substances , Refuse Disposal/methods , Osmosis
3.
BMC Bioinformatics ; 9: 386, 2008 Sep 19.
Article in English | MEDLINE | ID: mdl-18803844

ABSTRACT

BACKGROUND: Random community genomes (metagenomes) are now commonly used to study microbes in different environments. Over the past few years, the major challenge associated with metagenomics shifted from generating to analyzing sequences. High-throughput, low-cost next-generation sequencing has provided access to metagenomics to a wide range of researchers. RESULTS: A high-throughput pipeline has been constructed to provide high-performance computing to all researchers interested in using metagenomics. The pipeline produces automated functional assignments of sequences in the metagenome by comparing both protein and nucleotide databases. Phylogenetic and functional summaries of the metagenomes are generated, and tools for comparative metagenomics are incorporated into the standard views. User access is controlled to ensure data privacy, but the collaborative environment underpinning the service provides a framework for sharing datasets between multiple users. In the metagenomics RAST, all users retain full control of their data, and everything is available for download in a variety of formats. CONCLUSION: The open-source metagenomics RAST service provides a new paradigm for the annotation and analysis of metagenomes. With built-in support for multiple data sources and a back end that houses abstract data types, the metagenomics RAST is stable, extensible, and freely available to all researchers. This service has removed one of the primary bottlenecks in metagenome sequence analysis - the availability of high-performance computing for annotating the data. http://metagenomics.nmpdr.org.


Subject(s)
Database Management Systems , Databases, Genetic , Information Storage and Retrieval/methods , Internet , Phylogeny , Proteome/genetics , Software , Algorithms , User-Computer Interface
4.
J Chromatogr A ; 1108(1): 38-42, 2006 Mar 03.
Article in English | MEDLINE | ID: mdl-16426621

ABSTRACT

A sensitive, simple, specific, precise, accurate and rugged method for the assay and determination of enantiomeric purity of S-(-)-9-fluoro-6,7-dihydro-8-(4-hydroxypiperidin-1-yl)-5-methyl-1-oxo-1H,5H-benzo[i,j]quinolizine-2-carboxylic acid L-arginine salt tetrahydrate (WCK 771) in bulk drug has been developed. The method is RP-HPLC using endcapped C-18 stationary phase and chiral mobile phase. Chirality to the mobile phase was imparted with addition of beta-cyclodextrin. The UV-vis detector was operated at 290 nm. The flow rate of mobile phase was 2 ml/min. The method offers excellent separation of two enantiomers with resolution more than 2 and tailing factor less than 1.5. The method was validated for the assay of WCK 771 and quantification of R-(+)-enantiomer impurity in bulk drug. The calibration curves showed excellent linearity over the concentration range of 0.05-0.15 mg/ml for WCK 771 and 0.5-7.5 microg/ml for R-(+)-enantiomer. The precision (RSD) of the assay was 0.23%. The limit of detection and limit of quantitation of the method for WCK 771 were 0.015 and 0.06 microg/ml, respectively. The limit of detection and limit of quantitation for R-(+)-enantiomer were 0.025 and 0.09 microg/ml, respectively. The average recovery of the R-(+)-enantiomer was 100.5%. Same method was applied for the assay and determination of enantiomeric purity of WCK 771 in the intravenous formulation.


Subject(s)
Chromatography, High Pressure Liquid/methods , Fluoroquinolones/analysis , Chromatography, High Pressure Liquid/economics , Methicillin Resistance , Reproducibility of Results , Sensitivity and Specificity , Spectrophotometry, Ultraviolet , Staphylococcus aureus/drug effects , Stereoisomerism , beta-Cyclodextrins/chemistry
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