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Kontinuirano povećavanje upotrebe pesticida u suvremenoj poljoprivredi postaje neizbježno zbog učinkovitije proizvodnje hrane i samog porasta svjetske populacije. No, s druge strane sve je veća zabrinutost javnih institucija zbog štetnosti pesticida na ljude, druge organizme (domaće životinje, korisne insekte, pčele, ptice, ribe i dr.) i njihovu bio akumulaciju u samome tlu i svim vodenim ekosustavima. Stoga je u ovom radom analizirana fotolitička i fotokatalitička razgradnja s fotokatalizatorima titan dioksid (TiO2) i nanokompozitom titan doksida i ugljikovih nanocjevčica (TiO2/CNT) imidakloprida u pilot reaktoru s paraboličnim zrcalima (eng. compound parabolic collector, CPC). Prema kinetici razgradnje prvog reda, određene su približne konstante brzine fotolitičke razgradnje imidakloprida (k=0,0058 min-1) i fotokatalitičke razgradnje imidakloprida s TiO2 (k=0,0058 min-1) i s TiO2/CNT (k=0,00934 min-1). Primjenom TiO2/CNT fotokatalizatora može se postići brža razgradnja imidakloprida za 3,6 sati, u odnosu na fotokatalitičku razgradnju sTiO2. Analizom razgradbenih produkata, utvrđena su tri (m/z=212,0585; m/z=209,0589 te m/z= 211,0745) od četiri najčešća fotolitički razgradbena produkta imidakloprida, dok je svega jedan razgradbeni spoj (m/z= 274,0518) imidakloprida utvrđen pri fotokatalitičkoj razgradnji na TiO2 i TiO2/CNT fotokatalizatorima. To ukazuje na potrebu detaljnije analize, budući da su se eksperimenti provodili pri realnim uvjetima sunčeva zračenja. The continuous increase in the usage of pesticides in modern agriculture is becoming inevitable due to more efficient food production and the increase in world population. On the other hand, harmful effects of pesticides on humans and other organisms (domestic animals, beneficial insects, bees, birds, fish, etc.) cause concerns of public institutions due to their bio accumulation effect on the soil and aquatic ecosystems. Therefore, in this paper, the photolytic and photocatalytic degradation with photocatalysts titanium dioxide (TiO2) and nanocomposite of titanium dioxide and carbon nanotubes (TiO2/CNT) of imidacloprid in a pilot reactor with compound parabolic mirrors (CPC) was analysed. According to the kinetics of the pseudo first-order degradation, the apparent rate constants of the photolytic degradation of imidacloprid (k=0.0058 min-1) and the photocatalytic degradation of imidacloprid with TiO2 (k=0.0058 min-1) and with TiO2/CNT (k=0.00934 min-1) were determined. Faster degradation (3.6 hours) of imidacloprid can be achieved using TiO2/CNT photocatalyst in comparison to the usage of TiO2. The analysis of the degradation products revealed three (m/z=212.0585; m/z=209.0589 and m/z= 211.0745) out of the four most common photolytic degradation by-products of imidacloprid, while only one degradation compound (m/z = 274.0518) of imidacloprid was determined during photocatalytic degradation on TiO2 and TiO2/CNT photocatalysts. It indicates the need for a more detailed analysis since the experiments were carried out under the actual conditions of solar radiation.

Mikroonečišćivala su biološka ili kemijska onečišćivala koja ulaze u podzemne i površinske vode u tragovima kao rezultat ljudskih aktivnosti. Ti onečišćivači uključuju bezbroj prirodnih i sintetskih organskih spojeva, od kojih su mnogi označeni kao "nastali" uglavnom zbog toga što se tradicionalno ne nadziru ili ne reguliraju u uzorcima okoliša. Zbog njihovog negativnog utjecaja na okoliš i činjenice da uzrokuju zdravstvene, ekonomske i ekološke probleme, postali su pitanje od nacionalnog i globalnog značaja. Cilj ovog rada je analiza uzoraka s tri lokacije na području sjeverozapadne Hrvatske, kako bi se utvrdila prisutnost mikroonečišćivala poput farmaceutika, hormona, antibiotika i pesticida. Metoda koja je korištena za ispitivanje uzoraka u ovom radu je masena spektrometrija i tekuća kromatografija na uređaju Agilent 6350 Q-TOF LC/MS. Micro pollutants are biological or chemical pollutants that enter groundwater and surface waters as trace pollutants as a result of human activites These pollutants include a multitude of natural and synthetic organic compounds, many of which are labelled as “formed”, mainly because they are not traditionally controlled or regulated in environmental samples. Due to their negative impact on the enviroment and the fact that they cause health, economic and environmental problems, they have become an issue of national and global importance. The aim of this master thesis is to analyse samples from three locations in the area of north-western Croatia, in order to determine the presence of micro pollutants such as pharmaceuticals, hormones, antibiotics and pesticides. The method used to test the samples is mass spectrometry and liquid chromatography on an Agilent 6350 Q-TOF LC / MS.

Neadekvatna uporaba antibiotika u humanoj i veterinarskoj medicini dovodi do razvoja antimikrobne rezistencije, širenja otpornosti mikroorganizma te pojave njihovih ostataka u namirnicama životinjskog porijekla. Jedna od najčešće primijenjenih vrsta antibiotika su cefalosporini. Da bi ih adekvatno identificirali i kvantificirali bilo je potrebno razviti metodu i ispitati utjecaj metode za identifikaciju rezidua cefalosporina u mišićima goveda, svinje, peradi i ribe primjenom tekućinske kromatografije ultravisoke djelotvornosti sa spektrometrijom masa i analizatorom vremena preleta (UHPLC/Q-TOF-MS), što je ujedno i glavni cilj ovog rada. Također, validirana metoda za određivanje cefalosporina u mišićima različitih životinjskih vrsta visoke je specifičnosti, točnosti i preciznosti te zadovoljava kriterije o provođenju analitičkih metoda i tumačenju rezultata prema važećoj Uredbi komisije 2002/657/EZ. Metoda je primijenjena u rutinskoj analizi na Hrvatskom veterinarskom institutu. Na prisustvo 9 najčešćih cefalosporina testirana su 42 uzorka pri čemu nije pronađen ni jedan pozitivan uzorak. Inadequate use of antibiotics in human and veterinary medicine leads to the development of antimicrobial resistance, the spread of microorganism resistance and the appearance of their residues in food of animal origin. One of the most frequently used types of antibiotics are cephalosporins. In order to identify and quantify, it was necessary to develop a method and to examine the effect of the method for identifying the residual cephalosporin residues in cattle, pigs, poultry and fish muscles using ultra-high performance liquid chromatography and high resolution mass spectrometry (UHPLC/Q-TOF-MS), which is also the main objective of this paper. Validated method for the determination of cephalosporin in the muscles of different animal species is of high specificity, accuracy and precision and meets the criteria for the conduct of analytical methods and interpretation of results under the current Commission Regulation 2002/657 / EC. The method was applied in a routine analysis at the Croatian Veterinary Institute. In the presence of 9 most common cephalosporins, 42 samples were tested and no positive samples were found