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Metals are the backbone of modern civilization, indispensable for countless technological applications and crucial to many biological processes. But it is only through advanced technology that we have begun to fully understand their distribution and behavior, unlocking the potential for groundbreaking research in a variety of disciplines. This talk will introduce the audience to the important role of metals in fields such as geochemistry, environmental chemistry, materials science, and health assessment. From deciphering sediment deposition and their fate in landfills to studying the uptake of nutrients in biota and mitigating the harmful effects of pollution, metals offer invaluable insights into some of the most pressing scientific questions of our time. Interdisciplinary research has also unearthed exciting new applications for metals, such as linking their presence in certain organs to disease incidence and even exploring the mechanisms of bacterial survival in space. Overall, the study of metals is important for understanding a wide range of scientific phenomena, and as interdisciplinary research and new analytical techniques continue to advance, it is likely that the importance of metals in science will only continue to grow.

Once present in aquatic environment, metals may remain dissolved in the water as free ions, complexes and colloids, or adsorbed by suspended particulate matter, both of which serve as pathways of uptake into benthic animals. In many freshwaters, bivalves have a key role as filter- feeding, sediment-dwelling animals. The lower course of the Mrežnica River has been long exposed to various types of industrial loads which may adversely affect them. To assess the metal contamination of the Mrežnica River affected by anthropogenic influences, the concentrations of five non-essential elements (Ag, Cd, Cs, Pb and Tl) were measured in dissolved and particulate phases in the water and in the digestive gland of Unio crassus mussels at two sampling sites (the industrial area of Karlovac as a polluted site and a location upstream from the Town of Duga Resa as the reference site) in spring 2021. Water samples were filtered through a 0.45 μm pore diameter filter. The water filtrates containing dissolved metals were acidified with nitric acid, while the suspended material remaining on the filter was dried and then digested with nitric acid. Tissue samples were digested with mixture of nitric acid and hydrogen peroxide. The metal concentrations were measured using a high resolution inductively coupled plasma mass spectrometer. In dissolved and/or particulate phase in water, elevated Cs and Tl concentrations were detected at Karlovac, while Cd was higher at the reference site. Increased concentrations of these metals coincided with increased concentrations in U. crassus specimens. Although higher concentrations of Ag and Pb in the particulate phase were also detected at Karlovac, expected changes in the bioaccumulation of those metals were not observed in the digestive glands of U. crassus. Trend of higher concentrations of highly toxic metals at the Karlovac industrial zone indicated a potential risk for the Mrežnica River ecosystem. Thus, further monitoring of both water and biota is recommendable.

Nanodijamanti, odnosno dijamanti manji od 1 mikrometra, imaju izvrsna mehanička i optička svojstva, veliku površinu i visoku biokompatibilnost, što ih čini posebno atraktivnim za razne primjene. Posljednjih su godina privukli značajnu pozornost u nanomedicini kao nosači lijekova. Međutim, njihova sve veća uporaba znači i njihovu sve veću prisutnost u različitim dijelovima okoliša. Predavanje će upoznati polaznike škole s pojmom nanodijamanata, njihovim svojstvima i biotehnološkom primjenom, kao i ciklusom u okolišu kao posljedicom te primjene.

The research focuses on developing a bioleaching procedure for red mud samples. Bacteria were isolated using red mud from three different locations, after that, grown bacteria were applied to the red mud samples from Mostar, Bosnia and Herzegovina. Samples were heated to 100°C and filtered with MiliQ water. Geochemical analysis of red mud samples with bacteria, eluates and red mud on filter papers was carried out.

One of the main challenges of the modern world is the degradation of water quality due to human activities. The continuous interaction between sediment and water regulates the adsorption- desorption behaviour and thus the bioavailability of pollutants in rivers. The aim of this study was to compare the granulometric and geochemical characteristics of river sediments at five sites of the karst Krka River, which are under different anthropogenic impact: Krka River source (KRS, reference site), Krka River influenced by municipal wastewater (KRK-MWW), tributaries impacted by industrial effluents (Orašnica (TOR) and Kosovčica (TKO)) and by agricultural runoff (Butišnica (TBU)). After sampling the river sediments in July of 2021, carbonate content, particle size distribution, mineral oils, total organic carbon (TOC) and concentrations of Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn were determined. Carbonate content ranged 22.8 (TOR) - 92.8% (KRK), while the predominant particle size fractions were sand and silt at all locations. The particle size distribution indicated multiple material sources for the studied sediments. The obtained characteristics of the sediments were typical for karst rivers, but some parameters indicated anthropogenic impact. Compared to the other sites, levels of mineral oils and common industrial metals were high (Al≥Fe>Zn>Mn>Ba) at TOR and TKO, while TOC was elevated at TKO and KRK. Geochemical data of sediment from the Krka River watercourse indicated more evidence for industrial impact than urban and agricultural. Since pollutants in the sediment from karst rivers can easily become bioavailable, strict protection plans and continuous monitoring of the Krka River are recommended.

On the eastern Adriatic coast, manganese tailings from a historic ferroalloy plant (TEF) were left in (sometimes very harsh) atmospheric conditions after the plant closed in the late 1990s. These tailings near the old town of Šibenik are sometimes exposed to winds of up to 130 km/h and pose a health and environmental risk. Production at the plant began in 1900, and there has been an input of different contaminants in the surrounding area ever since. To determine the environmental impact of the tailings and dust and to assess whether there was potential for reuse detailed phase and geochemical analyses were carried out. These included X-ray powder diffraction (XRD), mass spectrometry (BCR sequential analysis and lithium borate fusion followed by ICP-MS) and SEM- EDS analysis. The analyses were carried out on sediment samples from two coves: a nearby cove (Mala Martinska Cove) and a more distant cove on the island of Žirje (Mala Stupica Cove), as well as on tailings and dust samples from factory roofs. Phase analysis revealed various manganese phases in tailings and dust (bustamite - (Ca, Mn)3 Si3 O9 ; and manganese oxides), and manganese phases were also detected in the sediments of Mala Martinska Cove. Geochemical analyses revealed 256 g/kg Mn in the dust sample, 1 g/kg Zn and 100 mg/kg REE. These values are lower than those currently required for reuse, but could become promising with advances in technology. About 500 mg/kg Mn was detected in the sediments of Mala Martinska Cove, while the Mn concentration in Mala Stupica Cove reaches ≈45 mg/kg, indicating the environmental impact of the tailings. Manganese is known to have several negative effects on organisms in different environments – one being changes in the regular functions of some immune parameters in organisms. Manganese becomes bioavailable through eutrophication and remains so for a long time if reducing conditions persist. Therefore, the concentrations of Mn and some other elements of interest determined in this study were compared with Norwegian and Australian sediment limit value legislation, as none exist in the European Union. Most of the values were found to be within the permissible limits.

Despite the large number of discovered truffle species, only a few of them are in great demand on the food market. Tuber melanosporum, commonly known as „the black diamond” in the gourmet culinary world, is considered to have the most complex aroma, while Tuber aestivum, widely appreciated in Mediterranean countries, is less aromatic. The decrease in productivity of this mushroom delicacy observed in the last decades, as well as forecasts based on climate models predicting a significant decline in European truffle yield in the near future, lead to a stark mismatch between supply and demand. These estimates, along with the difficulties concerning collecting, cultivating and storing truffles, have affected their market price. As a consequence, the truffle market became prone to fraudulent activities. In order to tackle the challenge of ubiquitous truffle fraud, numerous analytical tools were developed. Isotopic and elemental characterisation have successfully been used for tracing geographical origin of many food products. While previous studies have mostly focused on light elements’ isotopes, strontium isotope composition is underused, relatively new approach that has shown a great potential for the designation of origin. Considering the fact that truffles’ life cycle occurs underground and is completely dependent on the presence of the host tree, the 87Sr/86Sr ratios, being inherited from a particular geological environment, could provide crucial information for this process. Genetic and environmental variations, as well as the insufficiently explored soil ecology and its relationship with truffles and their host plants, may influence the Sr isotopic signatures of truffles. The present study aims to examine the Sr composition of truffles harvested in Croatia, as well as to evaluate the association between Sr isotopic profiles of truffles with those of soil and bark samples belonging to mycorrhizal partner trees obtained from the same sampling locations. For this purpose, 23 samples of summer truffle (T. aestivum) and 7 samples of black truffle (T. melanosporum), 30 corresponding soil samples and 26 corresponding tree bark samples were collected and analyzed. The total strontium concentration in the samples was determined by inductively coupled mass spectrometry, after microwave-assisted acid digestion, while the 87Sr/86Sr ratio was determined by multicollector ICP-MS. The obtained results show big variations in 87Sr/86Sr ratios within truffle samples (0.70838 – 0.71492), however, there is a good agreement between the Sr isotope ratio of truffles and the corresponding soil and tree bark samples, which suggests that the truffles reflect the local geochemistry of the environment in which they grow.

Predavanje je održano u sklopu međužupanijskog stručnog skupa na temu "Okolišne teme u učenju fizike" s ciljem upoznavanja publike s metodama i tehnikama koje se koriste u istraživanju okoliša, te njihovom primjenom kao primjera iz prakse u nastavi fizike u srednjim školama.

Znanstveni projekt “Transport, sudbina i toksičnost metal(oid)a otpuštenih iz ležišta industrijskog otpada (eng. “Transport, fate and toxicity of metal(loid)s released from industrial waste deposits”) istraživački je projekt koji u razdoblju od 1. prosinca 2019. do 30. studenog 2023. godine kroz program “Istraživački projekti” financira Hrvatska zaklada za znanost. Projekt FORtIS ima za cilj istražiti transport, sudbinu i toksičnost metal(oid)a otpuštenih iz ležišta industrijskih otpada utvrđivanjem svojstava i utjecaja na okoliš četiri različita odlagališta, koristeći, između ostalog, i svojstva procjednih voda. Naime, depoziti nastali odlaganjem industrijskog otpada predstavljaju dugotrajnu opasnost od onečišćenja kao potencijalna mjesta otpuštanja raznih onečišćujućih tvari, uključujući i metal(oid)e, s mogućnošću ozbiljnog zagađenja tla, površinskih i podzemnih voda u regiji, čak i desetljećima nakon njihovog odlaganja. Opseg negativnog utjecaja takvih odlagališta na okoliš ovisi o njihovim brojnim značajkama, uključujući njihov sastav i potencijal za izloženost te ekološki utjecaj. Procjedne vode se pritom smatraju potencijalnim transportnim mehanizmom kojim se otopljeni (