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In this work, the determination of different metals (i.e., Al, Cr, Cu, Mn, Ni and V) in engine lubricating oils by microwave plasma atomic emission spectrometry (MP AES) has been revisited. For this purpose, a new multinebulizer in combination with the standard dilution analysis (SDA) calibration methodology has been used. The microwave plasma is very unstable and may even extinguish when organic solvents are directly introduced. This problem can be avoided by the synergetic combination of the SDA calibration and the new multinebulizer since it allows the determination of analytes in complex matrices due to the simultaneous introduction of organic and aqueous solutions, favoring the plasma stabilization. Furthermore, the SDA calibration also corrects the matrix effects associated with complex matrices. For the purpose of comparison, the same study has been performed using conventional calibration methodologies (i.e., external calibration (EC), internal standard calibration (IS) and standard addition calibration (SA)). To compare the analytical performances, the analytical figures of merit (i.e., limit of detection and limit of quantification) and the accuracy (i.e., trueness and precision) of the results have been evaluated. The results obtained show very similar values for the SDA calibration compared to the other calibrations with a much lower consumption of reagents, resources and with a higher easiness of operation. In addition, the total analysis time has also been evaluated, which has emphasized the great advantage of the synergetic association of SDA calibration with the multinebulizer in chemical analysis.

Lithium, together with hydrogen and helium, were the only elements formed duringthe big bang. Lithium today, is a component in various products, some examples aregrease, ceramics, lithium-ion batteries and medication for bipolar disorder. Eventhough the knowledge of lithium’s interactions with biota and our environment islimited, the use of lithium is increasing. In humans, lithium is primarily absorbed in thesmall intestine through Na-channels. The average daily intake varies a lot, but in1985 it was estimated to range from 650 to 3100 μg for a 70 kg adult, according tointernational studies. However, it is not considered as a micronutrient and does nothave a recommended daily intake. Levels in some drinking waters are estimated toreach 170 μg L-1but no definite limit values are set. Humic substances are omnipresent in soil and freshwaters and is well known to formcomplexes with various cations such as most metals. In plants, the complexation ofcadmium and zinc with humic substances decreases their toxicity. However,currently, no studies have been published regarding if this is valid for animal cells aswell. To investigate if this is the case, in vitro tests were performed on Caco-2 cells,which originate from a colon carcinoma. These cells were exposed to a lithium concentration of 10 μg L-1in a nutrient medium for 2 hours. To a series of thesamples, humic acid was added to give a final concentration of 9.86 μg L-1 in thesolution to investigate if that would influence the lithium uptake. The study also includes a methodological evaluation if the performance of microplasma atomic emission spectroscopy (MP-AES) is suitable for the analyses of heavymatrices, e.g. nutrient medium and 1% Triton X solution. After optimization of instrumental parameters, it was concluded that MP-AES can beused for analysis of heavy and complex matrices. It requires, however, the use ofmatrix matched calibration solutions and addition of caesium as ionization buffer incombination with lithi, Litium är en viktig komponent in många produkter, bland annat smörjmedel, keramik,litium-jonbatterier och medicin mot bipolär sjukdom. Även fast dagens kunskap omlitium och dess interaktioner med miljö och organismer är begränsad, ökaranvändandet av litium. I människor absorberas litium primärt i tunntarmen genomNa-kanaler. Det dagliga intaget av litium varierar geografiskt och med livsstil och detfinnas inga bestämda gränsvärden. I USA var det dagliga intaget av litium 1985uppskattat att ligga kring 650 till 3100 μg hos en vuxen som väger 70 kg. Humusämnen är väl kända för att bilda komplex med flertalet metaller. I växter hardet påvisats att humusämnen kan bilda komplex med kadmium och zink vilketminskar toxiciteten av dessa för växten. Inga studier har dock hittats gällandehumusämnens eventuella möjligheter att minska toxiciteten av litium, eller andrametaller, hos djur eller människor. För att undersöka detta närmare har denna studiegjorts för att få ökad förståelse kring absorptionen av litium till Caco-2 celler samt föratt se om närvaro av humussyra kan påverka ett eventuellt upptag. Vidare presenteras resultat från en metodologisk utvärdering om MP-AES kananvändas för att kvantifiera litium i tyngre matriser, såsom näringsmedium för celleroch Triton X-100. Resultaten visar att MP-AES kan användas för dessa matriser genom att användamatrismatchade kalibreringslösningar och cesium som jonisationshämmare ikombination med korrigering av litiumsignalen med hjälp av signalen från internstandard. Sammanfattningsvis så absorberar Caco-2 celler litium och ingenindikation på att humusämnen påverkar detta upptag kunde hittas.

Worldwide the modern society produces vast amounts of waste materials containing strategic and valuable metals. Some of them are of substantial economic or environmental significance if controlled recovery of metals can be performed or if uncontrolled release to the environment occurs. By cultivating Agrostis capillaris on historical sulfidic mine waste the leachate composition can be altered and its volume reduced. In combination with additives such as bark compost and water works granules the concentration of several hazardous metals decreased significantly already after eight weeks. Limited actions can therefore be used to decrease the environmental impact from such waste. Shale in general contains considerable amounts of strategic metals. If naturally occurring microorganisms are provided with a source of nutrients, increased mobilization of strategic metals can be obtained. By using wood chips as the nutrient source the mobilization of vanadium and uranium increased significantly. Highest mobilization efficiency was observed when the carbon source was put on top of the shale. Analysis of strategic metals is often performed by argon plasma techniques such as ICP-QMS. However, the use of argon increases the analytical costs. If isotopic information is not needed and slightly higher uncertainties can be accepted, several strategic metals can successfully be quantified by the nitrogen plasma based MP AES. The analytical cost can then be cut with more than 99%.

Analysis of dissolved metals in acid rock drainage (ARD) with an Agilent 4100 MP AES instrument that combines a nitrogen micro plasma with atomic emission detection (MP AES) was compared with an ICP-MS. Sample preparation consisted only of filtration, acidification (HNO3 1%) and addition of internal standard elements after appropriate dilution. In these complex matrices the systems gave identical results provided that care was taken to avoid ionization. This was easily done by addition of CsNO3 which eliminated the need for matrix matching of calibration solutions. The use of internal standards is only needed for elements with known spectral interferences.