Določitev koncentracije težkih kovin v reki Meži z oceno njihovih negativnih vplivov na zdravje prebivalcev

Zavrl, Nejc (author), Novosel, Barbara (mentor)

Diplomsko delo obravnava okoljsko varnost Mežiške doline, za katero so znane povišane vrednosti težkih kovin kot posledica večletnega rudarjenja in predelave svinčevo-cinkove rude. Obravnavali smo vpliv degradiranega okolja in možne škodljive učinke na življenje prebivalcev v Mežiški dolini. V okviru eksperimentalnega dela smo določili vsebnost arzena, kadmija, kobalta, kroma, bakra, molibdena, niklja, svinca, selena in cinka v petih vzorcih vode in sedimenta reke Meže. Vsebnost izbranih težkih kovin smo izmerili z analitsko tehniko optične emisijske spektrometrije z induktivno sklopljeno plazmo (ICP-OES). Vzorčenje in analiza sta bila izvedena marca 2022. Dobljene koncentracije težkih kovin v površinski vodi in sedimentu smo primerjali s slovenskimi mejnimi vrednostmi ter mejnimi vrednostmi nekaterih drugih držav in organizacij. Meritve vzorcev površinske vode so pokazale, da v nobenem primeru ni prišlo do prekoračitev največjih dovoljenih koncentracij (NDK-OSK), ki so določene v slovenski zakonodaji. Izjema je kadmij, kjer so bile koncentracije pod mejo določljivosti, zato primerjava z nekaterimi mejnimi vrednostmi ni bila mogoča. Na enak problem smo naleteli tudi pri posameznih vzorčnih mestih nekaterih ostalih preiskovanih elementov. V površinski vodi reke Meže je nekoliko izstopala koncentracija bakra, ki je bila povišana na vseh vzorčnih mestih. V sedimentu reke Meže v primerjavi z ostalimi elementi izstopajo koncentracije kadmija, svinca in cinka, ki na posameznih vzorčnih mestih presegajo kritične imisijske vrednosti določene v slovenski zakonodaji. Na podlagi naših meritev smo ugotovili, da je najbolj onesnažen sediment v kraju Mežica. Določali smo tudi geo-akumulacijske indekse, faktorje kontaminacije, faktorje obogatitve in indeks obremenjenosti z onesnaževali, kjer so izmerjene koncentracije na različne načine primerjane glede na naravno prisotne koncentracije težkih kovin v okolju. Rezultati dokazujejo, da je onesnaženje reke Meže še vedno prisotno, kar potrjuje dejstvo, da tveganja za ekosistem in zdravje okoliških prebivalcev ostajajo.

• Language: Slovenian
• Keywords: težke kovine, ICP-OES, reka Meža, onesnaženost, vpliv na zdravje
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2022
• PID: 20.500.12556/RUL-139052
• COBISS.SI-ID: 121507587
• Publication date in RUL: 29.08.2022

Secondary language

• Language: English
• Title: Determination of heavy metals concentration in Meža river and assessment of their negative effects on population's health

Abstract

The diploma thesis deals with the environmental safety of the Mežica valley, for which elevated values of heavy metals are known as a result of many years of mining and processing of lead-zinc ore. We discussed the impact of the degraded environment and possible harmful effects on the lives of the inhabitants of the Mežica valley. In the experimental part, the content of arsenic, cadmium, cobalt, chromium, copper, molybdenum, nickel, lead, selenium and zinc was determined in five samples of water and sediment of the Meža river. The content of selected heavy metals was measured with the analytical technique of inductively coupled plasma optical emission spectrometry (ICP-OES). Sampling and analysis were performed in March 2022. The obtained concentrations of heavy metals in surface waters and sediment were compared with the Slovenian threshold values and the threshold values of some other countries and organizations. Measurements of surface water samples showed that the maximum permissible concentrations (NDK-OSK), which are set in Slovenian legislation, were in no case exceeded. The exception is cadmium, where concentrations were below the limit of quantification, so comparison with some limit values was not possible. The same problem was encountered at individual sampling sites for some other investigated elements. In the surface water of the Meža river, the copper concentration stood out slightly, because they were elevated at all sampling sites. In the sediment of the Meža river, the concentrations of cadmium, lead and zinc at individual sampling points exceed the critical immission values set out in Slovenian legislation. Based on our measurements, we found out that the most polluted sediment is in Mežica. We also determined geo-accumulation index, contamination factors, enrichment factors and pollutant load index, where the measured concentrations are in different ways compared to naturally occurring concentrations of heavy metals in the environment. The results prove that the pollution of the Meža River is still present, which confirms the fact that the risk to the ecosystem and the health of the surrounding population remains.

• Keywords: heavy metals, ICP-OES, river Meža, pollution, health effects