Dioxiner och metaller i Lövselefjärdens sediment : Förstudie av Lövselefjärdens sediment med avseende på föroreningar från ett tidigare sågverk

• Main Author: Karlsson, Elin
• Format: Bachelor Thesis
• Language: Swedish
• Published: Umeå universitet, Institutionen för ekologi, miljö och geovetenskap 2017
• Subjects: Dioxins; sawmill; TEQ; sediment; pollution; metals; Natural Sciences; Naturvetenskap; Canada; Northern Sweden
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-136133

The aim of this study was to determine if and how especially dioxins but also metals (arsenic, copper and chromium) has spread and deposited in the sediments of Lövselefjärden in northern Sweden. The study was also meant to determine if these pollutions could be related to the previous sawmill that was located near the bay. A gravity sampler was used to extract sediment cores from the bottom of Lövselefjärden. Five sample locations were used, and in one of the locations three different depths were sampled. The results show a similar distribution of the dioxin congeners between the samples taken in the sediment and the chemical preparation used at the sawmill. There was also a similarity between the proportions of metals in the sediment and the solution with metals used at the sawmill. It was there for concluded that the pollution mainly originates from the sawmill. The amount of dioxins was above the guidelines from both USA and Canada for most samples. For the metals, the guideline for arsenic in both USA and Canada was exceeded in all the samples, for copper the guideline from Canada was exceeded in all the samples and two of the samples exceeded the guideline from USA. The chromium amount did not exceed any guidelines in this study. The pollutions appear to be transported outwards towards the ocean and superimposed by sediment deposited later. Further studies to determine the bioavailability of the pollution and to determine further how the pollutions have spread and superimposed in the sediment are necessary.