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37 Uppsatser om Cadmium (Cd) - Sida 1 av 3

Avena Sativa - En hyperackumulator? : En studie av havres kadmiumupptag

The aim of our research was to investigate if oat is capable of extracting cadmium to such extent that it is usable in decontaminating polluted soils. We grew oat in a hydroponic culture during 28 days in a controlled environment and a total of 30 plants were used. The nutrient solutions were contaminated with cadmium of ten different concentrations after seven days. After harvesting the plants, the roots were separated from the shoots, placed in separate containers and then turned to ashes. The cadmium content was measured three times per sample in an atomic absorption spectrometer.Our results indicate that the ability of oat to extract cadmium from a solution is linearly dependent of the cadmium concentration of the solution.

Tungmetaller i metabolismen hos värphöns och slaktkycklingar

Mussel meal is a potential source of protein, with a good composition of amino acids, for laying hens and broiler chickens, and may replace the use of fish meal in organic poultry production. Lead and cadmium are heavy metals which occur in the environment and can be accumulated in mussels. When poultry are exposed to heavy metals, the metals are absorbed in the small intestine and distributed in the body in the form of ions, complexes or bound to proteins. In poultry, lead accumulates in bone tissue, liver and kidneys, while cadmium accumulates in liver and kidneys. Generally very low concentrations of these heavy metals occur in muscles of broilers which have been exposed to feed contaminated with cadmium or lead.

Kadmium i skånska vattendrag : en metodstudie i föroreningsmodellering

Modelling of pollutants is commonly used in research and at departments working with environmental issues. The need to use large amounts of data when modelling creates the opportunity for more generalised models with lower data demands. Aggregating functions into coarser elements is a sort of generalisation of actual features in nature.A development of a method and a modelling tool called ?KadmiumKalkylatorn? has been performed to model cadmium pollution in rivers in Skåne, Sweden. The water runoff has been multiplied with cadmium standard concentrations based on membership in landuse classes.

Kvalitet i brödvete :

The quality of bread wheat is a large subject to study. The quality rests on two legs. The first one is the inheritance of specific characters, which can be influenced through plant breeding and type of cultivar. The other one is the environmental influences, such as crop rotation, nutrition, harvest and storage. The latter factors are possibly to affect through cultivation practices, while other factors are not possible to influence on for the grower, such as seasonal changes of weather and the soil content.

Effect of liming and free Ca2+ on Cd uptake of carrots, Daucus carota

The level of Cadmium (Cd) in Swedish arable land has increased during the last century and the average concentration of Cd in the plough layer is today 0.23 mg/kg. The increase is mainly due to anthropogenic activities such as phosphorus fertilizing, liming, import of feed, and atmospheric deposition from industrial emissions. Cadmium in the soil will be taken up by crops and is thereby transferred to humans via food. Carrot is one of the crops of concern, both because it may contain quite high Cd concentrations and due to the large consumption in Sweden. In the body, Cd is stored mainly in the liver and the kidneys and may cause several diseases already at low concentrations.

Spårning av miljöstörande ämnen i Uppsala stads spillvattennät

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.

Växters upptag av spårämnen från rödfyr : ett odlingsförsök vid tre rödfyrshögar i Västra Götalands län

Burnt alun shale and lime is the residual product that was formed when alun shale was used as fuel to convert limestone to quick lime. The material contains arsenic, vanadium, molybdenum, cadmium, nickel, lead, and uranium among other elements. The aim of this paper is to examine the uptake of trace elements in vegetables grown on burnt alun shale and lime to determine whether or not the surrounding environment and humans are exposed to these elements by eating plant products. A cultivation trial was carried out where onion, carrot, and lettuce were grown on three mounds of burnt alun shale and lime in the Falköping area in Sweden. The treatments were burnt alun shale and lime mixed with peat, only burnt alun shale and lime, and a reference soil. The reference plots were natural soil mixed with peat adjacent to the mounds.

Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering

Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.

Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm

AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.

Tungmetaller i lakvatten : avskiljning med mineraliska filtermaterial

Four different kinds of filter-materials with reactive surfaces have been studied concerning their capacity to absorb heavy metals in leachate from a municipal waste deposit. The heavy metals studied were: lead, cadmium, copper, mercury, chromium, nickel and zinc. The leachate contains high levels of dissolved organic carbon (DOC) and has a high pH-value along with a high buffer capacity. These characteristics of the leachate make it difficult to remove pollutants and require efficient filters. The filters that were examined in the report are blast-furnace slag with CaO, sand covered with iron oxides, olivine and nepheline.

Möjligheter och hinder för att utöka omfattningen av RoHS-direktivet

The RoHS Directive was introduced in order to restrict hazardous substances in Electrical and Electronic Equipment, EEE. It currently restricts the use of six hazardous substances/compounds; cadmium, lead, mercury, hexavalent chromium, PBB, and PBDE. The RoHS Directive currently includes category 1-7 and 10 in the categories of EEE listed in Annex 1A to the WEEE-Directive (Waste of EEE). The aim with the report is to investigate and elucidate prospects and obstacles to increase the scope of RoHS. This report mainly considers the inclusion of product categories 8 (Medical Devices) and 9 (Monitoring and Control Instruments).

Gröna utsikter : En analys av hampas (Cannabis sativa L.) förutsättningar som energigröda i Sverige

Hemp is a versatile plant with many uses that has been around for thousands of years. The plant is highly adaptable andwill cultivate in almost any soil. It has excellent remediation properties and has shown to be relatively consistent when itcomes to crop yields. The aim of this literature survey is to examine how hemp can be used to be considered asustainable energy crop in Sweden through database searches and interviews. Hemps characteristics as an energy cropand its remediation properties is evaluated and compared with other plants that are used in Sweden.

Biomassa fo?r rening av metallkontaminerat grundvatten : En underso?kning av biomassamaterial i Uganda

Va?rlden sta?r info?r ett stort vattenfo?rso?rjningsproblem som ma?ste lo?sas ? sa? ma?nga som 884 miljoner ma?nniskor anva?nder idag potentiellt fo?rorenade vattenka?llor till sitt dricksvatten. Denna rapport fokuserar pa? ett av de drabbade la?nderna som a?r Uganda. Syftet med projektet a?r att underso?ka vilket/vilka av de fem olika ugandiska va?xterna; Erythrina abyssinica, Musa spp, Cyperus papyrus, Imperata cylindrica och Coffea canephora som a?r mest la?mplig fo?r rening av kadmium- och blykontaminerat grundvatten.

Förekomst av kontaminanter i importerad fisk : en litteraturstudie

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.

Är fytoremediering en realistisk metod för att rena marken runt Glasriket på arsenik, kadmium och bly?

Phytoremediation is a technique using the ability of plants to absorb pollutants in their biomass from contaminated soils and remediate it. The plants are then harvested and the soil gets purified. This method is more environmental-friendly than the normally used methods for soil remediation. Glasriket in Småland is an area with large amount of pollutants including arsenic, cadmium and lead. This area must be cleaned from these metals because of the high threat to the environment ant the health of people who live here.

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