Highlights of 2020
Environmental analytical chemistry
The role of trace elements and their impact to the environment and living organisms depend not only on their total concentration but also on chemical forms in which they are present. Our research is oriented to the development of new analytical procedures for speciation of elements like Al, Cr, Sn, Br, Pt, Ru, Ni, Zn etc. in environmental, food and biological samples. In speciation analysis, their concentration is determined by the use of isotope dilution inductively coupled plasma mass spectrometry technique.
Furthermore, we apply “in-house” synthesized and commercially available stable isotope enriched tracers to the investigations on the fate and role of trace elements in the environment and living organisms or to follow the species transformation during the sequence of steps in analysis. By precise measuring of the isotopic ratios of heavier elements we trace their transport in the environment and follow the geographical origin of food products. The research activities are focused also to the development of analytical methods for sizing and quantification of metal nanoparticles that are used in nanoremediation, medicine and food and to the development of speciation techniques and bio-imaging methods to determine the spatial distribution of target metallospecies in μ-sections of biological tissues.
Environment, nutrition and health
The main task is to support environment, health, and food related studies including all steps from planning, sampling, sample handling, sample preparation, substance detection and data interpretation. Food is considered not only as a source of energy, but also the main transport route is of an affordable way to prevent diseases.
Therefore, the general trend in food science is to link the food and the environment on one hand, and the food and the health on the other. The key research areas in all three domains are organic contaminants, element speciation, traditional and non-traditional stable isotopes, nanoparticles and food safety, traceability and authenticity.
Isotopic and elemental fingerprinting and chemical profiling (e.g. sugar, fatty acid, or even contaminant profiles) provide a robust analytical tool to determine the origin of food. Based on the measurements of the stable isotope content of a product or of a specific component of the product, means it is not only possible to determine the degree of adulteration, but also the region from which the product originates and even the year of production. The topic related to food safety applies to organic substances deriving from agricultural production practice, food additives and food contact materials, potentially toxic elements and their species and nano-sized particles (e.g., TiO2, Ag). Further, the research performed on human health contributes to increase knowledge on human exposure to potentially toxic compounds.
Biological and geochemical cycles
Our research focuses on study of biological, geological and chemical factors that are involved in the cycling of chemical elements (light elements: C, N, S, O, H; metals and metalloids: Hg, Cd, Pb, As, Se) in various environmental compartments at the scale of molecules to watersheds. We develop and employ chemical and biological techniques to follow elements transformations, their speciation and fractionation, including the use of stable and radioactive isotopes as tracers. Our goal is, in cooperation in wider medical and public health research, to provide and insight into the source-pathway-receptor-consequences relationships.
Clean technologies and waste management
Our research comprises: Analysis of trace-level persistent and new emerging contaminants in environmental samples (sediment, air, water, biological tissues); fate and cycling of organic contaminants in the environment (bioaccumulation, transformation, biodegradation, photodegradation,…) and simulating these processes in the laboratory; determination of transformation products formed during water treatment and environmental breakdown processes; biomonitoring; analysis of specific biomarkers and determination of their source in the environment by using stable isotopes.
Risk and environmental impact assessment
The work within this area focuses on education, research and consultancy in the field of environmental/risk assessment and modeling. Specifically this includes (i) development of methods and approaches; (ii) environmental studies on strategic and project levels (sustainability assessment, strategic environmental assessment, environmental impact assessment, safety analysis for hazardous industrial installations); (iii) development of indicators for sustainability and risk analysis; (iv) integration of environmental and risk assessment with spatial planning; (v) modeling of environmental transport and fate; (vi) environmental vulnerability modeling; (vii) epidemiological studies – analysis of exposure to environmental factors; (viii) environmental Cost-Benefit-Analysis; and (ix) training and mentoring.
Our monitoring programmes comprise environmental monitoring as well as human biomonitoring. We collaborate with national (e.g. the Environmental Agency of the Republic of Slovenia) and international agencies such as International Atomic Energy Agency. For the latter, we contribute to the GNIR - Global Network for Isotopes in Rivers and GNIP - Global Network for Isotopes in Precipitations.
The monitoring of natural radionuclides within the influential area of the former uranium mine and mill at Žirovski vrh is also performed. Among others, we participate in Off-Site Monitoring of the Krško Nuclear power plant by determinig radionuclides in various environmetal samples.
Our research in this area is focused on the characteristics and functioning of microorganisms in the environment. We are trying to understand different natural microbial systems in order to reproduce them artificially for biotechnological applications.
For this reason, we have opened up a new field, COLLOID BIOLOGY, which builds on the knowledge of colloid science, microbiology, molecular biology, microbial genetics and microbial ecology. We study microbial cells as particles, which are viable and respond actively to different stimuli from the environment. By understanding the properties of cell surfaces and the cell's physiological state, we are artificially building cellular consortia, like aggregates and biofilms, in order to study their development and functioning. Using these systems we can transform different bio-polymers into novel high-added value products or degrade chemically stable pollutants.
For our analyses, we implement different wet-lab techniques and bioinformatics approaches to determine the structure and function of bacterial consortia, describe genes and genomes and measure the activity of bacterial cells. Characterization of the physical properties of cells (by microscopy, zeta-potential measurements, flow-cytometry, etc.) and their behavior (by microfluidics, QCM, spectrophotometry, etc.) further helps us determine how the cells respond in different artificial systems.