The sampling and initial treatment of the material was carried out by IES. The lake sediment was collected in the Lago Maggiore (IT). The wet sediment was sieved over 2 mm sieves to remove larger particles. This wet material was first air dried, then dried in a ventilated oven at 105°C. The dry lumps were then broken down by a jawcrusher and the resulting material sieved over a 200 ìm sieve. The fraction that passed the sieve was milled using a Retsch mill and sieved again over a 90 ìm sieve. The fraction that passed that sieve (160 kg) was sent to the IRMM. There it was further ground by jet milling to a top particle size < 150 ìm. This resulted in 70 kg of powder. Homogenisation and sampling was carried out in a cone mixer with a semi-automatic filling device. 30 g of powder was filled in amber glass bottles with polyethylene inserts and plastic screw caps. 2000 units were produced. The water content was determined to be 1.3 ± 0.1 % (n = 20), by volumetric Karl Fischer titration. The particle size analysis using a Sympatec particle size analyser with a Helos measuring device showed a top particle size of 150 µm [4]. keywords: Environmental material, Soil/Sediment, Trace elements, Heavy metals
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