Nyomelem speciáció oldószer mentes mikroextrakciós módszerekkel = Application of solvent free microextraction methods for trace element speciation

Az összes krómtartalom meghatározására tengervízből izotóp hígításos nagyfelbontású induktiv csatolású plazma-ionizációs tömegspektrometriás módszert dolgoztunk ki, melynél a mintabevitelt GC elválasztás után közvetlenül oldottuk meg TFAs derivatizációval. A módszert továbbfejlesztve összevetettük a hatásfokokat ECD EI-MS és ICP-Ms detektálásnál.Megállapítottuk, hogy A metilhigany és etilhigany vegyületek eltérően viselkednek mikrohullámú besugárzás hatására, mely nagy mértékben befolyásolhatja a speciációs meghatározásukat. Lúgos feltárás és fenilezési rekció kidolgozásával SPME-GC-AFS módszert dolgoztunk ki halminták higanyspecieszeinek meghatározására. | For the determination of total chromium concentration in seawater an isotope dilution sector field inductively coupled plasma mass spectrometry method was developed, wher for the sample introduction a GC method after TFA derivatization was used. The efficiency of the method was compared using ECD, EI-MS and ICP-MS detection. The degradation behaviour of methylmercury and ethylmercury under microwave irradiation was invesigated, where the effect of irradiation will change the detectability of species. An SPME-GC-AFS determination of methyladet mercury compunds was developed after alkaline sample degradation and phenylation derivatization

Bioaccumulation of total mercury in the earthworm Eisenia andrei

Earthworms are a major part of the total biomass of soil fauna and play a vital role in soil maintenance. They process large amounts of plant and soil material and can accumulate many pollutants that may be present in the soil. Earthworms have been explored as bioaccumulators for many heavy metal species such as Pb, Cu and Zn but limited information is available for mercury uptake and bioaccumulation in earth- worms and very few report on the factors that influence the kinetics of Hg uptake by earthworms. It is known however that the uptake of Hg is strongly influenced by the presence of organic matter, hence the influence of ligands are a major factor contribut - ing to the kinetics of mercury uptake in biosystems. In this work we have focused on the uptake of mercury by earthworms ( Eisenia andrei ) in the presence of humic acid (HA) under varying physical conditions of pH and temperature, done to assess the role of humic acid in the bioaccumulation of mercury by earthworms from soils. The study was conducted over a 5-day uptake period and all earthworm samples were analysed by direct mercury analysis. Mercury distribution profiles as a function of time, bioac- cumulation factors (BAFs), first order rate constants and body burden constants for mercury uptake under selected conditions of temperature, pH as well as via the dermal and gut route were evaluated in one comprehensive approach. The results showed that the uptake of Hg was influenced by pH, temperature and the presence of HA. Uptake of Hg 2 + was improved at low pH and temperature when the earthworms in soil were in contact with a saturating aqueous phase. The total amount of Hg 2 + uptake decreased from 75 to 48 % as a function of pH. For earthworms in dry soil, the uptake was strongly influenced by the presence of the ligand. Calculated BAF values ranged from 0.1 to 0.8. Mercury uptake typically followed first order kinetics with rate constants determined as 0.2 to 1 h ? 1 .Scopus 201