Evaluation of cot mattress inner foam as a potential site for microbial generation of toxic gases.

Recent reports of biovolatilisation of phosphorus and antimony by anaerobic bacteria and of leaching of phosphorus and antimony fire-retardant additives from PVC cot mattress covers, indicate that the polyurethane inner-foam of cot mattresses could be a site for generation of toxic gases of group 15 elements. A toxic gas hypothesis for sudden infant death syndrome (SIDS) involving polyurethane foam of cot mattresses was proposed and tested experimentally. Levels of antimony, phosphorus, arsenic and bismuth were determined at four sites for 44 SIDS and 50 control (no death) cot mattress foams.

Microwave digestion of "residual fuel oil" (NIST SRM 1634b) for the determination of trace elements by inductively coupled plasma-mass spectrometry.

A microwave procedure for the digestion of the NIST 1634b reference material "residual fuel oil" in closed pressurized vessels was developed in an attempt to facilitate routine analysis and obtain reproducible conditions or comparable results. The influence of sample size, reagent composition and volume, microwave power, and duration of heating on the digestion procedure was studied. Pressure and temperature inside the reaction vessels were monitored to determine the progression of the reaction and to develop optimal conditions.

Determination of 'arsenosugars' in algae with anion-exchange chromatography and an inductively coupled plasma mass spectrometer as element-specific detector.

The retention behavior of four naturally occurring dimethylarsinoylribosides with -CH2-CHOH-CH2X (X = OH, HO3POCH2CHOHCH2OH, SO3H, OSO3H) as aglycones, of arsenous acid, arsenic acid, methylarsonic acid, and dimethylarsinic acid was investigated on a Hamilton PRP-X100 anion-exchange column with aqueous solutions of ammonium dihydrogen phosphate (20 mmol/L) in the pH range of 3.8-9.0 as mobile phase.

Mercury determination with ICP-MS: signal suppression by acids.

When mercury is quantified by ICP-MS under routine conditions (external calibration) in reference materials, which require mineralization with nitric acid, the experimental concentrations are almost always unacceptably low in comparison to certified values. Sorption of mercury on the Teflon surfaces of the digestion vessels, changes in the viscosity of the aspirated solutions, in the efficiency of the nebulization, in the aerosol transport, and memory effects cannot be responsible for the low results. The intensity of a mercury signal is strongly dependent on the concentration of nitric acid (and other mineral acids) in the measured solutions.

Selenium-enriched sprouts. A raw material for fortified cereal-based diets.

The selenium supply in almost all European countries, including Austria and Germany, is below the recommended daily intake. In these countries, selenium fortification of foods and the use of selenium supplements are quite popular to compensate for low Se intake from diets. In general, wheat (Triticum aestivum) is known to be a good source for bioavailable selenium, and many studies have been performed to enrich selenium in wheat by selenium fertilization of the soil.

Role of bound zinc in dimer stabilization but not enzyme activity of neuronal nitric-oxide synthase.

Nitric-oxide synthases (NOS) are homodimeric proteins and can form an intersubunit Zn(4S) cluster. We have measured zinc bound to NOS purified from pig brain (0.6 mol/mol of NOS) and baculovirus-expressed rat neuronal NOS (nNOS) (0.

Milk consumption, smoking and lead concentration in human hair.

Trace elements in hair samples were examined in 79 medical and sports students in Vienna and 77 biology students in Rome (ages 19-31 years). Lead concentration was determined by inductively coupled plasma mass spectrometry. The effect of smoking on lead levels is confirmed.

Characterization of recombinant human endothelial nitric-oxide synthase purified from the yeast Pichia pastoris.

Human endothelial nitric-oxide synthase (eNOS) was expressed in the methylotrophic yeast Pichia pastoris, making use of the highly inducible alcohol oxidase promoter. The recombinant protein constituted approximately 3% of total protein and was largely soluble (>75%). About 1 mg of purified eNOS was obtained from 100-ml yeast cell cultures by affinity chromatography of crude cell supernatants.

Determination of bromide, bromate and other anions with ion chromatography and an inductively coupled plasma mass spectrometer as element-specific detector.

An implementation of the Dionex IonPac AS12A analytical column with an element-specific ICP-MS detection is described for the simultaneous determination of halogen and oxyhalogen anions, sulfate, phosphate, selenite, selenate and arsenate. The chromatographic separation was achieved in less than 4 min with an aqueous 11 mM (NH4)2CO3 (pH 11.2, adjusted with aqueous ammonia) as eluent.

Uptake of arsenic-betaines by the mussel Mytilus edulis.

Mussels (Mytilus edulis) were exposed to trimethyl(carboxymethyl)arsonium bromide (arsenobetaine, C-1 betaine), trimethyl(2-carboxyethyl)arsonium bromide (C-2 betaine), or trimethyl(3-carboxypropyl)arsonium bromide (C-3 betaine). Arsenic was accumulated by the mussels in all cases but the efficiency of uptake decreased with the number of methylene units in the carboxyalkyl group. Arsenobetaine (C-1 betaine) was the most readily accumulated, followed by the C-2 betaine (70% as efficient as arsenobetaine) and the C-3 betaine (approximately 7%).

Biovolatilization of antimony and sudden infant death syndrome (SIDS).

1. The aerobic filamentous fungus S. brevicaulis IMI 17297 methylated antimony from Sb2O3 substrate, with the formation of gaseous trimethylantimony (TMA).

Antimony leaching from cot mattresses and sudden infant death syndrome (SIDS).

1. Polyvinyl chloride (PVC) cot mattress covers from SIDS cases were investigated as potential sources of soluble (potentially ingestable) antimony in the cot environment. 2.

Urinary arsenic species in Devon and Cornwall residents, UK. A pilot study.

First void urine samples were collected from 24 residents in an area of past intense mining and smelting activity of arsenical ores. Seven samples were also taken from a control village. The arsenic species in the urine were separated and quantified with an HPLC-ICP-MS system equipped with a hydraulic high-pressure nebulizer.

Characterization of arsenosugars of biological origin using fast atom bombardment tandem mass spectrometry.

A fast atom bombardment (FAB) mass spectrometric method has been developed for characterizing arsenosugar compounds. These compounds are of particular interest not only because their biochemistry requires further investigation but also because they are present at relatively high concentrations in commercial seaweed food products. FAB was used for the efficient generation of gas-phase ions of the various arsenosugar compounds.