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Široka paleta materialov, ki se uporablja v prehrambni embalaži, lahko pomembno vpliva na zdravje in okolico. Zato je pomembno pridobiti podatke o vsebnosti kemikalij, ki prehajajo iz embalaže v prehrano in okolje. Področje raziskav v magistrski nalogi so nonilfenoli (NP) in oktilfenoli (OP), njuni etoksilati (NP1EO, NP2EO, OP1EO, OP2EO) ter bisfenol A (BPA). Vse naštete spojine najnovejše raziskave uvrščajo med motilce delovanja endokrinega hormonskega sistema. Delo predstavlja modifikacijo analiznih postopkov za določevanje izbranih alkilfenolov, ki jih predlaga standardna metoda SIST ISO 18857-2. Ključne uvedene spremembe standardne metode so pri izolaciji analitov iz vzorcev, predvsem v ekstrakcijskem postopku na trdno fazo in dodatnem čiščenju ekstraktov vzorcev. Prilagodili smo tudi predlagano GC/MS metodo z vpeljavo sklopljene tehnike tandemske masne spektrometrije (MS/MS). Pri določanju tehnične mešanice nonilfenolov in nonilfenol etoksilatov, ki so sestavljeni pretežno iz razvejanih para izomerov, smo preizkusili tehniko tandemske masne spektrometrije z dvema prekursorskima ionoma, ki zadovoljivo opišeta večino predstavnikov nonilfenolnih izomerov. Z vpeljano GC/MS/MS metodo smo v različnih vzorcih vode in v predmetih splošne rabe uspeli sočasno določiti vse preiskovane spojine (NP, OP, NP1EO, NP2EO, OP1EO,OP2EO in BPA ). Pri določanju analitov v podzemni in odpadni vodi smo optimizirali ISO standardiziran postopek SPE ekstrakcije tako, da smo pred kromatografsko analizo vpeljali vmesno stopnjo čiščenja ekstraktov. Ekstrakcijo smo optimizirali z uporabo polnila – Lichrolut EN, ki zaradi svoje sestave in velike površine omogoča dobro izolacijo analitov. Za najučinkovitejše čiščenje SPE ekstraktov se je izkazalo čiščenje na Florisilu. Prilagojeno metodo smo preizkusili pri določanju alkilfenolov (NP in OP), njihovih mono- in di-etoksilatov ter BPA v različnih površinskih, odpadnih in podzemnih vodah. Metoda se je izkazala za uspešno tudi pri kvantitativnem določanju alkilfenolov v različnih vzorcih predmetov splošne rabe (PSR), predvsem v plastičnih folijah, ki se uporabljajo za embalažo živil. Hkrati smo z migracijskimi poskusi preverili prehod (migracijo) NP iz plastičnih folij v modelne raztopine. V vseh preiskovanih folijah, ki se uporabljajo za embalažo zamrznjene hrane, smo zaznali NP v koncentraciji do 110 mg/kg folije. Največja količina NP je prehajala v modelno vodno raztopino 95 % etanola (od 28 do 65 mg/kg folije), ki simulira maščobna živila. Predlagana modificirana standardna metoda SIST ISO 18857-2, z vpeljano GC/MS/MS metodo, bi se lahko uporabila za določanje alkilfenolov in njihovih etoksilatov. Materials used in the packaging industry may have unknown health and environmental issues associated with their wide spread use. There is a need for information on quantity and identity of chemicals released into the environment from the packaging materials. This research focuses on nonylphenol (NP), octylphenol (OP), with their ethoxylates (NP1EO, NP2EO, OP1EO, OP2EO) and bisphenol A (BPA) based on recent issues of interest concerning the endocrine hormone system. Standard analytical technique for the determination of alkylphenols, proposed by the standard method ISO 18857-2, has been accompanied by isolation of analytes from samples, especially in the extraction process of the solid phase and in further purification of sample extracts. Analytical steps have also adapted the proposed GC/MS method with the introduction of the tandem mass spectrometry (MS/MS). Detection of the technical NP and NPEO, which consist mainly of branched para-isomers, was improved by tandem mass spectrometry technique, with two parent mass fragments which adequately describe the majority of the representative nonylphenol isomers. The established GC/MS/MS method enabled the detection all investigated compounds simultaneously. The optimization of the ISO standardized procedure of the SPE extraction has been tested on groundwater and waste water samples. This has been achieved by adding an intermediate level of treatment extracts before instrumental analysis. The Lichrolut EN filller was used during extraction that enable the isolation of analytes due to its large surface area. The chromatography purification on Florisil was used for cleaning the SPE extracts. The work also expands to determination of the alkylphenols (NP and OP), their mono-and diethoxylates and BPA present in different samples of: surface, waste and groundwater. The method enabled the quantitative determination of alkylphenols in food packaging samples tested. At the same time we have also studied the migration of NP from plastic films into the food simulants. All of the tested plastic films for deep freeze food packaging contained NP up to 110 mg/kg film. The presence of NPs in the range of 28 to 65 mg/kg plastic film has been identified in the fatty food simulants. Therefore it is proposed that modified standard method ISO 18857-2 followed by GC/MS/MS could be employed for determination of alkylphenols and their related compounds. |
