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Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus ochraceus and Penicillium verrucosum. It has been found and analysed in several foods and feeds. Owing to its toxicity and occurrence in food and feed, the European Community has issued directives and some countries have their own regulations for OTA contents in food, feed and beverages. This work describes a method for the determination of OTA in mulled and red wine. It is based on combined anion exchange/reversed-phase clean-up and was analysed by liquid chromatography coupled with tandem mass spectrometry (multiple reaction monitoring). The method was validated with natural contaminated and spiked wine samples with OTA contents from 1.34 to 3.48 g kg1. Owing to its accuracy, good reproducibility and repeatability, this easy method is a good alternative to liquid chromatographyfluorescence detection methods.
Certified reference materials (CRMs) are a versatile tool for quality assurance in the chemical laboratory. In the case of acrylamide analysis, the availability of appropriate materials was rather limited. This lack of acrylamide matrix CRMs has now been overcome by the development of two European reference materials (ERM) for the determination of acrylamide in food (crispbread, ERM-BD272, and rusk, ERM-BD274). This article describes the preparation of the materials, provides the results of the homogeneity and stability studies, and presents and discusses the outcome of the certification studies. Expert laboratories from different European countries took part in the certification studies using various analytical methods. The acrylamide mass fractions were certified to 980 µg kg-1 for crispbread and 74 µg kg-1 for rusk.
ISO Guide 35 deals with RM stability issues and scrutinizes the evaluation of stability testing results under the assumption that either there is no trend at all (a rather rare situation), or any observed deterministic change is insignificant and thus can be neglected. However, market demands for reliable reference materials are obviously not limited to stable or at least seemingly stable materials. In many analytical applications, analytes and measurands under consideration are known, or at least suspected, to be unstable on time scales that may vary widely from measurand to measurand. The Federal Institute for Materials Research and Testing (BAM) has developed (and successfully uses) an integrated approach in its certification practice. The approach is based on an initial stability study and subsequent post-certification monitoring. Data evaluation is model-based and takes advantage of all information collected in the stability testing scheme(s). It thus allows one to deal with any kind of instability observed, to assess limiting time intervals at any stress condition in the range tested, to estimate a final expiry date for materials with detected instabilities or the maximum admissible re-testing interval for seemingly stable materials, and to assess maximum admissible stress loads during delivery of the material to the customer. The article describes (and exemplifies) typical study layout, the model selection, and the integrated data assessment.
Anwendungen von Bioziden in Materialien für Außenanwendungen sind mögliche Quellen für Biozide in Umweltkompartimenten infolge von witterungsbedingten Auswaschprozessen. Im Bericht werden Leachingprozesse und -parameter als auch Methoden zu deren Untersuchung unter Labor- und Freilandversuchsbedingungen beschrieben. Vorteile und Grenzen der verschiedenen Herangehensweisen zur Untersuchung von Leachingprozessen werden diskutiert. Standardisierte Auswaschtests sowie in der Fachliteratur publizierte Auswaschexperimente werden zusammenfassend dargestellt. Es wird beschrieben, wie Leachingdaten gemäß Technischem Leitfaden zur Biozidprodukten-Richtlinie 98/8/EG für eine Risikobewertung genutzt werden. Ein alternativer Ansatz zur mathematischen Modellierung von Leachingtest-Daten wurde erprobt und wird im Bericht erläutert. Potentiell lassen sich mit dem vorgeschlagenen Ansatz bestimmte gegenwärtig auftretende Schwierigkeiten bei der Risikobewertung umgehen.
Applications of biocides in outdoor materials are potential sources of biocides in environmental compartments due to leaching processes under weathering conditions. Leaching processes and parameters as well as methods to investigate leaching processes under laboratory and semi-field conditons are described in the report. Benefits and limitations of different test approaches are discussed. Standardised leaching tests as well as leaching experiments reported in scientific literature are listed. The application of leaching data for risk assessments according to the Technical Guidance Documents for the Biocidal Products Directive (98/8/EC) is described. An alternative approach for mathematical modelling of leaching data was tested and is Explained in the report. Certain difficulties that currently appear during risk assessments may be circumvented by the proposed approach.