Degradation products of profenofos as identified by high-field FTICR mass spectrometry: Isotopic fine structure approach.

This study was performed to identify the degradation products of profenofos "a phenyl organothiophosphate insecticide" in raw water (RW) collected from the entry point of Metropolitan Water Works Authority "Bangkaen, Thailand" and ultrapure water (UPW) with and without TiO under simulated sunlight irradiation. Degradation of profenofos was followed with ultrahigh performance liquid chromatography (UHPLC) and follows pseudo first-order kinetic. Accordingly, high-field FTICR mass spectrometry coupled to an electrospray ionization source was used to reveal the degradation routes of profenofos and the isotopic fine structures (IFS) elucidations to approve the chemical structures of its degradation products.

Ozone photolysis of paracetamol in aqueous solution.

The degradation of a paracetamol (N-acetil-para-aminofenol) aqueous solution (C (0) P = 5 mmol L(-1)) is studied in a bench-scale setup by means of simple ozonation (O3) and ozonation catalyzed with UV light (O3/UV) in order to quantify the influence of UV light on the degradation process. The results have shown that under the adopted experimental conditions (25°C, applied ozone dose = 9.8 mg L(-1) and gas flow rate of 20 L h(-1)) both oxidative systems are capable of removing the substrate with mineralization degrees up to 51% for ozonation and 53% for O3/UV.

Photolysis pathway of imazapic in aqueous solution: ultrahigh resolution mass spectrometry analysis of intermediates.

Direct degradation of imazapic, an herbicide of the imidazoline family, has been investigated in aqueous solution at different concentrations, pH values, and temperatures. The efficiency of the photodegradation process has been evaluated through degradation rate constants that could be fitted best with pseudo-first-order kinetics ( Ct = C0 e(- kt )). Ultrahigh resolution mass spectrometry (FTICR/MS) was used in electrospray ionization mode as a tool to study the photolysis process on a molecular level, whereas UV-vis and high-performance liquid chromatography/mass spectrometry analysis were used to follow, by time, the evolution of the intermediates.

Ecotoxicity of biocomposites based on renewable feedstock - preliminary studies.

The aim of the work was to study the biodegradation process of biocomposites prepared from renewable resources and the ecotoxicological assessment of their biodegradation products. Biocomposites from modified starch reinforced with various cellulose fibers were prepared by the extrusion process. Biodegradation studies were carried out according to the ISO respirometic method.

Triclosan determination in water related to wastewater treatment.

Triclosan in the waste, river and sea water samples collected in Hong Kong was analyzed by using gas chromatography-ion trap mass spectrometry method. (13)C(12)-triclosan was used as internal standard for the quantitative analysis. Water samples were prepared and cleaned-up by using a C(18) solid-phase extraction cartridge.

Characterization of imazamox degradation by-products by using liquid chromatography mass spectrometry and high-resolution Fourier transform ion cyclotron resonance mass spectrometry.

The photodecomposition of imazamox, a herbicide of the imidazolinone family, was investigated in pure water. The main photoproducts from the photolysis were followed over time by liquid chromatography mass spectrometry and structures were proposed from exact mass determinations obtained by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. The method comprised exact mass determination with better than 0.

From dioxin to drug lead--the development of 2,3,7,8-tetrachlorophenothiazine.

Polychlorinated dibenzo-p-dioxins are persistent environmental pollutants. The most potent congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), causes a wasting syndrome and is a potent carcinogen and immunosuppressant in the rat at high doses. However, low doses cause opposite effects to some of those observed at higher doses, resulting in chemoprevention, stimulation of the immune system, and longevity in experimental animals.

Changes in PCDD/PCDF formation processes during instationary phases of combustor operation--exemplified by the use of Cl4DD isomer patterns.

In this paper results of various measurement campaigns at different municipal waste incineration (MWI) plants concerning the change of the PCDD/PCDF isomer distribution in the crude gas during transiently impaired combustion conditions are presented. The focus is on the Cl4DD isomer distributions exemplarily for all other homologue groups to demonstrate the change in PCDD/PCDF formation mechanism at transient combustion conditions. Additionally to crude gas samples, at one plant filter and boiler ash were investigated simultaneously to determine if there is any difference in the isomer distribution between the matrices.

Substitution patterns in aromatic rings by increment analysis. Model development and application to natural organic matter.

The aromatic region of two-dimensional heteronuclear 1H, 13C NMR spectra of natural organic matter and related materials (e.g., 1H and 13C chemical shifts ranging from approximately 5 to 10 and 80 to 140 ppm, respectively) is highly complex and difficult to interpret using conventional approaches.

Photocatalytic degradation of triazophos in aqueous titanium dioxide suspension: identification of intermediates and degradation pathways.

The photocatalytic degradation of triazophos in aqueous TiO2 suspension has been studied in a photoreactor operating with simulated solar radiation. The decrease in triazophos concentration followed first-order kinetics with a half-life of 4.76+/-0.

Effects of a branched p-nonylphenol isomer (4(3',6'-dimethyl-3'-heptyl)-phenol) on embryogenesis in Lymnae stagnalis L.

The tertiary branched alkyl-chain isomers of p-nonylphenol (NP) are perceived to have more estrogenic potency than its constituent secondary and primary straight alkyl-chain isomers. Investigations with single tertiary branched isomers of NP can therefore contribute toward the elucidation of the mechanisms of toxicity and estrogenicity of NP. A single tertiary branched alkyl-chain isomer (4(3',6'-dimethyl-3'-heptyl)-phenol) was used in studies to determine its effects on embryonic growth and mortality in Lymnaea stagnalis L.

On-line immunoaffinity column-liquid chromatography-tandem mass spectrometry method for trace analysis of diuron in wastewater treatment plant effluent sample.

An on-line immunoaffinity column with liquid chromatography/tandem mass spectrometry (IAC-LC-MS/MS) method for the determination of diuron in water matrices was described. This method used a sol-gel immunoaffinity column (20 mm x 4 mm I.D.

Development of a capillary electrophoresis-mass spectrometry method for the determination of formaldehyde releasers as their hydrolysis products and amino alcohols from metal working fluids.

Metal working fluids (MWFs) are widely used as lubricants and coolants for different industrial operations. Biocides are ingredients of MWFs to control the microbial growth; derivatives of hexahydrotriazines and oxazolidines are generally used. Because of the lack of appropriate characterization, an existing capillary electrophoretic method for their quantification was improved.

Development of a capillary electrophoretic method for the analysis of low-molecular-weight amines from metal working fluid aerosols and ambient air.

A method for the determination of low-molecular-weight amines from indoor and ambient air was developed using a concentration device followed by CE coupled with indirect spectrophotometric and mass spectrometric detection that enables a reliable, rapid-response and easy-to-operate method. In indirect detection method, the selected amines were separated from interfering metal ions and amino alcohols present in the samples with an imidazole-based buffer with ethanol and EDTA as modifier. By replacing imidazole with ammonium, the final buffer was applicable for MS detection for the analytes with m/z higher than 50.

PCDD/F and other micropollutants in MSWI crude gas and ashes during plant start-up and shut-down processes.

Nonstationary combustion conditions at municipal solid waste incineration (MSWI) plants cause increased crude gas concentrations of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and other products of incomplete combustion (PIC). Such transient conditions occur, e.g.

[Determination of anions in the products of ozonation of reactive dye by ion chromatography].

A method for the determination of anions in the degradation products of C. I. Reactive Red 120 by ozonation was investigated.

Detection of royal jelly adulteration using carbon and nitrogen stable isotope ratio analysis.

Stable isotope ratios ((13)C/(12)C and (15)N/(14)N) were measured in royal jelly (RJ) samples by isotope ratio mass spectrometry (IRMS) to evaluate authenticity and adulteration. Carbon and nitrogen isotope contents (given as delta values relative to a standard, delta(13)C, delta(15)N) of RJ samples from various European origins and samples from commercial sources were analyzed. Uniform delta(13)C values from -26.

Trace and mineral elements in royal jelly and homeostatic effects.

Royal jelly from Apis mellifera is a highly active natural biological substance and is probably one of the most interesting raw substances in natural product chemistry. Trace elements play a key role in the biomedical activities associated with royal jelly, as these elements have a multitude of known and unknown biological functions. For this reason concentrations of 28 trace (Al, Ba, Sr, Bi, Cd, Hg, Pb, Sn, Te, Tl, W, Sb, Cr, Ni, Ti, V, Co, Mo) and mineral (P, S, Ca, Mg, K, Na, Zn, Fe, Cu, Mn) elements were systematically investigated in botanically and geologically defined royal jelly samples.

Development and application of a sol-gel immunosorbent-based method for the determination of isoproturon in surface water.

An immunosorbent was fabricated by encapsulation of monoclonal anti-isoproturon antibodies in sol-gel matrix. The immunosorbent-based loading, rinsing and eluting processes were optimized. Based on these optimizations, the sol-gel immunosorbent (SG-IS) selectively extracted isoproturon from an artificial mixture of 68 pesticides.

High-performance liquid chromatography-tandem mass spectrometry for identification of isoflavones and description of the biotransformation of kudzu root.

High-performance liquid chromatography-tandem mass spectrometry has been used to identify isoflavone aglycones and glycosides in kudzu root. Fourteen isoflavones were detected. Among these, six were identified by comparison with authentic standards.

Inhibition of progesterone receptor activity in recombinant yeast by soot from fossil fuel combustion emissions and air particulate materials.

Numerous environmental pollutants have been detected for estrogenic activity by interacting with the estrogen receptor, but little information is available about their interactions with the progesterone receptor. In this study, emission samples generated by fossil fuel combustion (FFC) and air particulate material (APM) collected from an urban location near a traffic line in a big city of China were evaluated to interact with the human progesterone receptor (hPR) signaling pathway by examining their ability to interact with the activity of hPR expressed in yeast. The results showed that the soot of a petroleum-fired vehicle possessed the most potent anti-progesteronic activity, that of coal-fired stove and diesel fired agrimotor emissions took the second place, and soot samples of coal-fired heating work and electric power station had lesser progesterone inhibition activity.

Oxidant denuder sampling for analysis of polycyclic aromatic hydrocarbons and their oxygenated derivates in ambient aerosol: evaluation of sampling artefact.

The concentrations of some polycyclic aromatic hydrocarbons (PAH) and oxygenated PAH (O-PAH) can be changed by oxidation reactions during sampling. This can lead to an over- or underestimation of the corresponding adverse health effects. The aim of this study was the evaluation of these sampling artefacts.

Development of new rat monoclonal antibodies with different selectivities and sensitivities for 2,4,6-trinitrotoluene (TNT) and other nitroaromatic compounds.

Five new rat monoclonal antibodies (mAbs) for 2,4,6-trinitrotoluene (TNT) and other nitroaromatic compounds, including, especially, the metabolite 2-amino-4,6-dinitrotoluene (2-ADNT), are described. Five heterogeneous, competitive enzyme-linked immunosorbent assays (ELISAs) were developed. Assay 1 uses mAb DNT4 3F6 as recognition element and gives a standard curve for TNT in 40 mmol L(-1) phosphate buffered saline (PBS) with a test midpoint (IC50) of 0.

A new, versatile field immunosensor for environmental pollutants: development and proof of principle with TNT, diuron, and atrazine.

This paper presents a new, versatile, portable miniaturized flow-injection immunosensor which is designed for field analysis. The temperature-controlled field prototype can run for 6h without external power supply. The bio-recognition element is an analyte-specific antibody immobilized on a gold surface of pyramidal structures inside an exchangeable single-use chip, which hosts also the enzyme-tracer and the sample reservoirs.

Effect of linear alkylbenzene sulphonate (LAS) on the mineralization, metabolism and uptake of 14C-phenanthrene in a model ecosystem (water-lava-plant-air).

The aim of this work was to evaluate the effect of linear alkylbenzene sulfonate (LAS, 200 mg l(-1)) on the fate of phenanthrene in a model ecosystem "water-lava-hydrophytes-air". The experiments were conducted using two closed cultivation chamber systems. Rushes (Juncus effesus) were selected as a representative hydrophyte.