Title Toksičnost uzoraka nakon fotolize Title (english) Toxicity of samples after photolysis Author Dora Lastovčić Mentor Danijela Ašperger (mentor)Committee member Danijela Ašperger (predsjednik povjerenstva)Committee member Šime Ukić (član povjerenstva)Committee member Svjetlana Krištafor (član povjerenstva)Granter University of Zagreb Defense date and country 2022-09-20, Croatia Scientific / art field, NATURAL SCIENCES Abstract Ksenobiotici su strane tvari antropološkog porijekla i onečišćivači okoliša, u kojem završavaju zbog neučinkovitog uklanjanja iz otpadnih voda. Cilj ovog rada je odrediti toksičnost ksenobiotika prije i nakon fotolize pri kiselim, neutralnim i lužnatim pH-vrijednostima (4, 7 i 10), kako bi se utvrdila ekotoksičnost ispitivanih komponenti, smjese njihovih razgradnih/transformacijskih produkata kao i ispitivanje potencijalno negativnih efekta pH-vrijednosti. Niska pH-vrijednost moguća je u okolišu zbog kiselih kiša, dok se visoka vrijednost javlja u prirodnim vodama s povišenom koncentracijom mineralnih tvari (kalcij, magnezij, kalij) kao posljedica trošenja stijena. Fotoliza se vrlo često odvija u okolišu zbog prisutnosti Sunčeve svjetlosti te se može odvijati u različitim medijima. To je proces koji djeluje razgradno na veliki broj kemikalija te može dovesti do nastanka razgradnih/transformacijskih produkata koji su toksičniji od izvornih komponenata. Stoga je zadatak ovog rada simulirati uvjete fotolize koja utječe značajno na transformaciju ksenobiotika u okolišu te odrediti njihovu toksičnost. Ispitivana je toksičnost uzoraka pesticida (acetamiprida, klotianidina, tiakloprida) i antiparazitika (mebendazola, albendazola i febantela). Toksičnost je mjerena u skladu s normom HRN/EN ISO 11348-1:2000 primjenom luminiscentne bakterije Vibrio fischeri, fotoliza je provedena u uređaju SuntestCPS+ u trajanju od 300 min, a analiza uzoraka provedena je u kromatografskom sustavu HPLC-DAD. Svi su uzorci (10 mg L^-1) pokazali toksičnost pri određenim uvjetima. Rezultati mjerenja pokazali su neočekivano veliku toksičnost nakon fotolize uzorka klotianidina samo pri uvjetima pH=10 i uspješno djelovanje fotolize na razgradnju tiakloprida, mebendazola te albendazola bez povećanja toksičnosti. Na uzorcima febantela izmjerena je toksičnost uzrokovana fotolizom hidrolitičkog produkta u lužnatom mediju (pH=10). Potrebno je provesti preciznije analitičke analize kako bi se identificirali razgradni produkti nastali tijekom procesa fotolize.
Abstract (english) Xenobiotics are foreign substances of anthropological origin and pollutants of the environment, where they end up due to ineffective removal from wastewater. The aim of this work is to determine the toxicity of xenobiotics before and after photolysis at acidic, neutral and alkaline pH-values (4, 7 and 10), in order to determine the ecotoxicity of the examined components, mixtures of their degradation/transformation products, as well as the examination of potentially negative effects of the pH-value. A low pH-value is possible in the environment due to acid rain, while a high value occurs in natural waters with an increased concentration of mineral substances (calcium, magnesium, potassium) as a result of rock deterioration. Photolysis often takes place in the environment due to the presence of sunlight, with possible effect in different media. It is a process that degrades a large number of chemicals and can lead to the formation of degradation/transformation products that are more toxic than the original components. Therefore, the task of this paper is to simulate the conditions of photolysis, which significantly affects the transformation of xenobiotics in the environment, and to determine their toxicity. The toxicity tests were applied on samples of pesticides (acetamiprid, clothianidin, thiacloprid) and antiparasitics (mebendazole, albendazole and febantel). Toxicity was measured in accordance with the HRN/EN ISO 11348-1:2000 norm using the luminescent bacterium Vibrio fischeri, photolysis was performed in a SuntestCPS+ device for 300 min, and sample analysis was performed in an HPLC-DAD chromatographic system. All samples (10 mg L^-1) showed toxicity under certain conditions. The measurement results showed an unexpectedly high toxicity after photolysis of the clothianidin sample at pH=10 conditions and a successful effect of photolysis on the degradation of thiacloprid, mebendazole and albendazole without increasing toxicity. The toxicity measured on febantel samples was caused by the photolysis of the hydrolytic product in an alkaline medium (pH=10). It is necessary to carry out more precise analytical analyzes in order to identify the degradation products formed during the photolysis process.
Keywords
ksenobiotici
fotoliza
pesticidi
antiparazitici
toksičnost
Vibrio fischeri
Keywords (english)
xenobiotics
photolysis
pesticides
antiparasitics
toxicity
Vibrio fischeri
Language croatian URN:NBN urn:nbn:hr:149:887948 Study programme Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry Type of resource Text File origin Born digital Access conditions Closed access Terms of use Created on 2023-03-03 10:20:00
