Inter-laboratory validation of liquid chromatography-tandem mass spectrometry multi-mycotoxin determination in animal feed - method transfer from the reference laboratory to regional laboratories.

Introduction: The results are presented of the inter-laboratory validation of a liquid chromatography-tandem mass spectrometry method for the determination of eight mycotoxins (aflatoxin B1, deoxynivalenol, fumonisin B1, fumonisin B2, ochratoxin A, toxin T-2, toxin HT-2 and zearalenone) in animal feeds.

Material And Methods: This study was an essential part of the method's transfer from the National Reference Laboratory to six regional laboratories in Poland working in the official survey of mycotoxins in feed. The laboratories received a batch of standard solutions, blank samples and quality control materials on which to perform analysis with one procedure and different liquid chromatography-tandem mass spectrometry conditions.

Application of chemometrics in river water classification.

The main aim of this work is focused on water quality classification of the Brda river (Poland) and evaluation of pollution data obtained by the monitoring measurement during the period 1994-2002. The study presents the application of selected chemometric techniques to the pollution monitoring dataset, namely, cluster analysis, principal component analysis, discriminant analysis and factor analysis. The obtained results allowed to determine natural clusters and groups of monitoring locations with similar pollution character and identify important discriminant variables.

Characterization of natural organic matter (NOM) derived from sewage sludge compost. Part 2: multivariate techniques in the study of compost maturation.

This study presents the results of chemometric data analysis which describes the maturation of sewage sludge compost. The compost was characterized at different stages of maturation by various chemical and spectroscopic parameters including carbon and nitrogen content, humic substances content, UV-Vis and 13C NMR. The data set of compost characteristics was analyzed using multivariate methods: cluster analysis (CA) and principal component analysis (PCA).

Characterization of natural organic matter (NOM) derived from sewage sludge compost. Part 1: chemical and spectroscopic properties.

In this study changes in the properties of natural organic matter (NOM) were studied during composting of sewage sludge in a laboratory experiment using the pile method. Typical physicochemical parameters were measured during 53 days of composting including humic fractions. The effects of humification on the molecular properties of humic acids (HA) were investigated by 13C CP/MAS NMR spectroscopy.

The comparison study of compost and natural organic matter samples.

Sewage sludge is a serious problem facing modern wastewater treatment plants. One of the methods to safely utilize the sludge is through composting and the agricultural use of the final product. In this study the compost samples from municipal sewage sludge are compared to the natural, rich in organic matter samples.