The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

Transformation of inorganic mercury (Hg) to Methyl mercury (MeHg) is a biotic process that is proposed to be conducted primarily by sulphate reducing bacteria (SRB). The formation of MeHg is of great interest because it is the mercury species that biomagnifies to the greatest extent in the aquatic food webs; about 90 % of all Hg in fish is MeHg. Our understanding of factors involved in the production of MeHg is very important for making a reliable risk assessment. The purposes of this study were to investigate the different factors that control the solubility of Hg and the production of MeHg in a contaminated lake sediment. The lake Ala-Lombolo, Kiruna municipality, is well-known to be contaminated by mercury from different sources. Sediment cores were sampled at three different locations (N, SW and SE) in the lake and divided in three different layers; 0-5, 5-10 and 10-15 cm.

Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.

The project this report is handling has been implemented on NBB, Nordisk Bilbelysning AB in Linköping. The company produces and develops lightning and searchlights for all types of vehicles. Lately NBB´s supplier of electronics, OSRAM, has developed a mercuryfree xenon lightsource. Mercury is one of the most hazardous environmental waste and to get rid of the mercury entirely in the lightsource is a big step that means alot for the environment.This lightsource will be placed in one of NBB´s worksearchlights called My, and will be sold as an alternative to mercurycontaining searchlights. NBB wants to put an environmental label on this product and they want to have essential information about the product that is needed for the production.

A literature review of contaminants; cadmium, methylmercury, dioxins, and PCB, for eleven different fish species (Greenland halibut, gilt headed bream, sea bass, wolffish, hoki, ocean perch, angler, Nile perch, pangasius, red snapper and tilapia) that were selected in concurrence with the National Food Administration. The result can be used by the National Food Administration to gain further knowledge about the different fish species to be able to continue to give advice to varied risk category and the public. The gilt headed bream and sea bass were the only fishes whose values for mercury exceeded the limit of 0,5 mg/kg (EU Reg. 1881/2006). In the angler, Nile perch and pangasius the mean value of mercury didn?t exceed the limit, however in some individuals the mercury content did exceed what is allowed.

High levels of Hg in fish in Swedish lakes have been a problem along time in Sweden. The major concern is production and accumulation of the most toxic form of mercury; Methyl mercury (MeHg). Consequently, in about half of our 83 000 lakes fish contain concentrations above the recommended limit for human consumption of 0,5 mg mercury per kg fresh weight (most of it in the form of MeHg). Consumption of fish containing too high levels of MeHg may cause problems for both humans and animals. Three major sources of MeHg in surface waters are: 1) runoff from terrestrial areas, 2) deposition from the atmosphere, and 3) internal production of MeHg in lakes and streams. The aim of this study was to investigate the effect of clear-cutting on the concentration of Hg and MeHg into draining streams.

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorsprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2012:21.

This report is an inventory of the street lighting in half of the residential estates owned by Karlstad Bostads AB, a public housing company. The inventory was made to reduce the environmental impact of the street lighting. From the inventory an estimation of the total installed power and the energy consumption was made. The total estimated power of the street lighting was 125 kW and the energy consumption was 500 000 kWh/year with an estimated running time of 4 000 h/year. The dominating source of light was 125 W discharge mercury lamps.

Forestry is increasing on an industrial scale where collection of logging residues takes a greater part. This has resulted in more machinery and heavy machinery driving in the clear felled area, this increases the risk of soil damage that will occur in the form of soil compacting and rutting in the clearings. This affecting on the nature in a negative way and especially in rivers and lakes that are affected by siltation and acidification leading to increased levels of heavy metals and Methyl mercury. The purpose of this study was to investigate why there is damage to the ground when working with the slash in forest management from the forest officer point of view. A self-designed questionnaire was used and 45 questionnaires were sent out to various companies all over Sweden.

The aim of this study was to examine the current and historic mercury(Hg) load of the lake Storjuktan due to its recent exposure to a local potential source of Hg in form of the Sulphide mine Blaikengruvan(2006) and an earlier potential sources of Hg-load, the damming of the lake(1960s). Sediments were extracted using a HTH-sampler, freeze-dried, and analyzed for tot-Hg, LOI and activity of 210Pb and compared to samples extracted prior to the opening of the mine(2006). Constant initial concentration (CIC)-dating model was used for dating the samples. Low levels of Hg (100ng/g) were found throughout the lakes sediment. The highest levels of Hg(220ng/g) was detected at a depth of 4-5cm dating back to the mid 1970:s, suggesting that increased levels of atmospheric Hg rather than damming of the lake has caused the increase of Hg.

Printed and painted wallpaper on a weaved fabric backing was a common way to decorate homes in Sweden during the eighteenth and nineteenth centuries. Not much is written about the craftsmanship in relation to the hanging of these wallpapers and even less about the conservation of the objects. Even so, many wall segments remain in situ and in museums and are more often than not in dire need of conservation such as deacidification and consolidation. These are composite objects, consisting of cellulose materials with different properties along with adhesives and paints. Analysis of the materials is required to ensure safe handling and choice of conservation materials, and to establish a treatment plan which will be executed in several steps. This thesis aims to identify these steps and develop a method for conserving the wall segments with suitable materials, preferably without altering the source material to any significant degree.

The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).

When facing the fact that high yielding dairy cows has an increasing energy requirements, the practice of adding lipid supplements such as concentrates rich in palm oil and/or palm oil industry by-products become more common. Palm oil containing high levels of C16:0 causes high levels of free fatty acids (FFA) which are linked to larger milk fat globules (MFG) which affect the reaction of lipolysis resulting in rancid flavour and processing problems. Instead of using palm oil, rapeseed oil rich in C18:1 C18:2 can be used. In order to evaluate the effect of added C18:0 and C16:0 on milk lipolysis, 30 Swedish Red lactating dairy cows including 15 multiparous (MP) and 15 primiparous (PP) cows were randomly divided in three groups resulting in 3 10 cow-groups (5 PP and 5 MP cows per group) and fed one out of three concentrate mixtures: control (C), a standard concentrate mixture with no fat added; palmitate (P) as C plus the addition of palmitate methyl ester (10 % in DM basis); and stearate (St) as C plus the addition of stearate methyl ester (10 % in DM basis). Milk yield was registered, and milk samples were collected and analysed for milk composition, FFA content and size of MFG.

To the sewer systems households, industries and other activities are connected. The wastewater is collected at treatment plants where a nutritious sludge is produced. The sludge does not only contain nutrients, but also hazardous substances originating from different activities in society. To reduce the flow of hazardous substances to treatment plants and to create a sustainable recycling of plant nutrients the Swedish Water & Wastewater Association has developed the certificate system REVAQ. This certificate requires a good quality of the sludge but also that the treatment plants maps the origin of the unwanted substances.

The effect of methyl jasmonate on resistance against the large pine weevil (Hylobius abietis) in Scots pine and Norway spruce seedlings. A field experiment was conducted in order to determine the dose-response effects of methyl jasmonate (MJ) on growth and defence to pine weevils in Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) and to compare the effect of MJ between pine and spruce. In addition a complementary greenhouse experiment was conducted with the same aims as above and to determine the amount of resin ducts and their correlation to the feeding of pine weevils. The field experiment was conducted on a fresh clear cutting in Garpenberg, southern Dalarna in central Sweden. The experiment consisted of 30 blocks with three kinds of containerized seedlings: 2-year old spruce, small pine (before shoot elongation) and 1-year old pine (already shoot elongated). They were all exposed to 4 treatments 14 days prior to the experiment: control, 25 mM/L MJ, 50 mM/L MJ and 100 mM/L MJ. Data on weevil damage and seedling growth were collected after the first and the second growing season. The seedlings in the greenhouse experiment were of the same kind and were exposed to the same treatment as the ones in the field experiment.