114 research outputs found
A novel approach to model 4 decades of marine chemical data
The awareness of the negative effects of chemical pollution in the sixties has led to an increased concern on the chemical status of the marine environment in the following decades. International regulation in Europe started with the Oslo and Paris convention in the seventies, later on leading to the OSPAR commission. At national level, extended research on chemical pollutants in marine sediments and marine biota was done within the “Project Mer/Projekt Zee” from 1970 to 1976. Since then, a long series of research and monitoring projects was conducted, reporting on the chemical status of the Belgian Part of the North Sea.
Within the 4demon project, a major work package focused on the collection, quality control and intercalibration of more than 40 years of data on heavy metals and polychlorinated biphenyls. In this presentation, the modelling approach and results on sediment data will be presented.
Within current OSPAR and MSFD monitoring on chemical pollution, variability in location, seasonality, grain size, etc. is reduced thanks to standardized OSPAR guidelines. This facilitates comparability of data within and between regions and assessments based on 5-15 year timetrends are frequently made. Within more than 40 years of pollution data, variability is much larger, and multiple issues should be tackled to intercalibrate the data: changes in sampling locations and analyses methods over time, missing essential metadata, sample analysis on different grain size fractions,… Therefore, existing time trend modelling approaches could not be applied within the 4Demon project. An alternative approach, focused on cluster analysis and different normalisation procedures was proposed. A parametric linear mixed effect model was used to integrate all data into consistent long term time lines which give a view on PCB and heavy metal pollution on a large time frame.
Acknowledgement
We want to thank the Belgian Science Policy Office (BELSPO) for the financial support of the 4Demon project.</p
Contaminants in organically and conventionally produced winter wheat ( Triticum aestivum
Concentrations of strontium, barium, cadmium, copper, zinc, manganese, chromium, antimony, selenium and lead in the equine liver and kidneys
Determination of As, Asi, Cd, Pb, Cu and Zn in chocolate (PT-2017-NRL-TE-FASFC). Final report on the 2017 Proficiency Test organised by the National Reference Laboratory for Trace Elements in Food and Feed.
PT-2014-NRL-TE-FASFC Determination of Cu, Zn, As, Asi, Cd and Pb in wine. Final report on the 2014 interlaboratory comparison organised by the National Reference Laboratory for Trace Elements in Food and Feed
Determination of As, Asi, Cd, Pb, Cu and Zn in rice wafers (PT-2016-NRL-TE-FASFC).Final report on the 2016 Proficiency Test organised by the National Reference Laboratory for Trace Elements in Food and Feed.
Determination of As, (iAs), Cd, Pb, Cu, Hg and Zn in liquid follow-on formulae manufactured from soya protein isolates (PT-2015-NRL-TE-FASFC). Final report on the 2015 interlaboratory comparison organised by the NRL for Trace Elements in food and feed.
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