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Transformations of nano-enabled products during simulated usage and disposal
Thesis (MSc)--Stellenbosch University, 2023.
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| Format: | Thesis |
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Stellenbosch : Stellenbosch University
2023
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| _version_ | 1867613998601469952 |
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| access_status_str | Open Access |
| author | Currie, Dailin Jade |
| author2 | Malgas-Enus, Rehana |
| author_browse | Currie, Dailin Jade Malgas-Enus, Rehana |
| author_facet | Malgas-Enus, Rehana Currie, Dailin Jade |
| author_sort | Currie, Dailin Jade |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MSc)--Stellenbosch University, 2023. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/128377 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:45:01.662Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2023 |
| publishDateRange | 2023 |
| publishDateSort | 2023 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/128377 Transformations of nano-enabled products during simulated usage and disposal Currie, Dailin Jade Malgas-Enus, Rehana Tancu, Yolanda Walters, Chavon Stellenbosch University. Faculty of Science. Dept. of Chemistry and Polymer Science. Nanostructured materials -- Toxicology Ultraviolet-visible action spectroscopy Nanotechnology UCTD Thesis (MSc)--Stellenbosch University, 2023. ENGLISH ABSTRACT: Nano-enabled products (NEPs) contain various types of engineered nanomaterials (ENMs) to enhance their functions. The use of nanomaterials (NMs) is unregulated, and many NEPs are not labelled to contain NMs, as such they are regarded as emerging contaminants of concern. Thus, their potential toxic effects posed to the environment and on living organisms remain largely unknown. This research project aimed to investigate the behavior, fate, and potential toxicity of NMs embedded into commercial products comparable to their pristine counterparts. The selected products were sunscreen and foundation (containing TiO2 NMs), Covid-19 face mask and plaster (containing Ag NMs), and lip mask and eye mask (containing Au NMs). Furthermore, Ag-PVP, Ag-citrate, TiO2 and Au-citrate nanoparticles (NPs), similar to those which form part of the NEPs, were synthesized and diluted to the working concentrations as metal NPs contained in NEPs. An experimental (used) and a control (unused) sample were prepared to monitor the NPs in NEPs. Ultraviolet-visible (UV-Vis) spectroscopy analysis was carried out routinely to determine the NP existence and to monitor their behavior in aqueous solution over time and it was determined that NMs from NEPs and pristine NMs undergo changes as evident from their absorbance shifts in wavelength over time. Transmission electron microscopy analysis (TEM) was used to verify the morphology and size of NPs. Plasters were found to contain flower-shaped and rod-shaped NPs (35.10nm± 11.0nm), NPs in Covid-19 face masks were not quantifiable, sunscreen contained TiO2 nanorods (119.52 ± 129.00 nm and 17.16 ± 84.63 nm in control and in 86.39 ± 48.37 nm used sample), foundation contained angular and near-spherical NPs (184.87 ± 65.07 nm and 216.25 ± 116.47 nm), eye masks contained agglomerated and fragmented Au NPs and Au NPs in lip masks were not quantifiable. Inductively Coupled Plasmon Optical Emission Spectroscopy/ Mass Spectroscopy (ICP-OES/MS) was employed to determine their metal concentrations. The concentration of Ag NMs contained in plaster and mask sample solutions were in the range of 0.01 mg/L to 0.05 mg/L, TiO2 NPs contained in sunscreen and foundation samples were 0.05 mg/L; and Au NMs contained in eye and lip mask sample solutions were 0.05 mg/L. A simulated wastewater treatment plant (WWTP) using synthetic wastewater, monitored the fate and behavior of engineered NPs (ENPs) from both pristine vs. NEPs. Samples were collected at various points of the WWTP including the influent, aeration chamber, settlement vessel, and effluent. Results from UV-Vis, ICP and TEM analysis of the effluent indicated that NMs persisted throughout the WWTP and were thus not effectively captured by sludge formed in the settlement vessel-whilst transforming into ionic form. Finally, the toxicity potential of NEPs and ENPs toward two plant species of Lactuca sativa (lettuce seeds) and the African daisy Osteospermum 'Soprano Purple' plants were investigated by monitoring their seed germination and flowering, respectively. It was found that NPs from ENPs and NEPs have comparable effects on the flowering and germination of daisies and lettuce seeds, respectively. AFRIKAANSE OPSOMMING: Nano-geaktiveerde produkte (NGP'e) bevat verskeie tipes gemanipuleerde nanomateriale (GNM'e) om hul funksies te verbeter. Die gebruik van nanomateriale (NM'e) is ongereguleer, en baie NGP'e word nie gemerk om NM'e te bevat nie, as sodanig word hulle beskou as opkomende kontaminante wat kommerwekkend is. Dus bly hul potensiële toksiese effekte op die omgewing en op lewende organismes grootliks onbekend. Hierdie navorsingsprojek het ten doel gehad om die gedrag, lot en potensiële toksisiteit van NM'e wat in kommersiële produkte ingebed is, vergelykbaar met hul ongerepte eweknieë, te ondersoek. Die geselekteerde produkte was sonskerm en onderlaag (wat TiO2 NM’e bevat), Covid-19 gesigmasker en pleister (wat Ag NM’e bevat), en lipmasker en oogmasker (wat Au NM’e bevat). Verder is Ag-PVP, Ag-sitraat, TiO2 en Au-sitraat nanopartikels (NP'e), soortgelyk aan dié wat deel vorm van die NGP'e, gesintetiseer en verdun tot die werkende konsentrasies as metaal NP'e vervat in NGP'e. 'n Eksperimentele (gebruikte) en 'n kontrole (ongebruikte) monster is voorberei om die NP'e in NGP'e te monitor. Ultraviolet-sigbare (UV-Vis) spektroskopie-analise is gereeld uitgevoer om die NP-bestaan te bepaal en om hul gedrag in waterige oplossing oor tyd te monitor en daar is vasgestel dat NM'e van NGP'e en ongerepte NM'e veranderinge ondergaan soos blyk uit hul absorpsieverskuiwings in golflengte oortyd. Transmissie-elektronmikroskopie-analise (TEM) is gebruik om die morfologie en grootte van NP’e te verifieer. Daar is gevind dat pleisters blom- en staafvormige NP'e (35.10 ± 11.0 nm) bevat, NP'e in Covid-19-gesigmaskers was nie kwantifiseerbaar nie, sonskerm bevat TiO2 nanorods (119.52 ± 129.00 nm en 17.16 ± 84.63 in beheer monster, en 86.39 ± 48.37 nm gebruikte monster), fondament het hoekige en naby-sferiese NP'e bevat (184.87 ± 65.07 nm en 216.25 ± 116.47 nm), oogmaskers bevat geagglomereerde en gefragmenteerde Au NP'e en Au NP’e in lipmaskser was nie kwantifiseerbaar nie. Induktief-gekoppelde plasmonoptiese emissiespektroskopie/massaspektroskopie (ICP-OES/MS) is gebruik om hul metaalkonsentrasies te bepaal. Die konsentrasie van Ag NM’e vervat in pleister- en maskermonsteroplossings was in die reeks van 0.01 mg/L tot 0.05 mg/L, TiO2 NP’e vervat in sonskerm- en onderlaagmonsters was 0.05 mg/L; en Au NM’e vervat in oog- en lipmasker-monsteroplossings was 0.05 mg/L. 'n Gesimuleerde afvalwaterbehandelingsaanleg (WWTP) wat sintetiese afvalwater gebruik, het die lot en gedrag van gemanipuleerde NP'e (GNP'e) van beide ongerepte tenoor NGP'e gemonitor. Monsters is by verskeie punte van die WWTP versamel, insluitend die influent, belugtingskamer, nedersettingsvat en uitvloeisel. Resultate van UV-Vis-, ICP- en TEM-analise van die uitvloeisel het aangedui dat NM'e regdeur die WWTP voortduur en dus nie effektief vasgevang is deur slyk wat in die nedersettingsvat gevorm is nie - terwyl dit in ioniese vorm getransformeer word. Laastens is die toksisiteitspotensiaal van NGP'e en GNP'e teenoor twee plantspesies van Lactuca sativa (slaaisade) en die Afrika-madeliefie Osteospermum 'Sopran Purple'- plante ondersoek deur onderskeidelik hul saadontkieming en blom te monitor. Daar is gevind dat NP'e van GNP'e en NGP'e vergelykbare effekte op die blom en ontkieming van madeliefies en blaarsaad onderskeidelik het. Masters 2023-03-07T07:20:00Z 2023-08-30T13:11:14Z 2023-03 2023-03-07T07:20:00Z 2023-08-31T09:18:32Z 2023-03-07T07:20:00Z 2023-08-31T09:18:32Z 2023-03 Thesis https://scholar.sun.ac.za/handle/10019.1/128377 en_ZA Stellenbosch University application/pdf application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Nanostructured materials -- Toxicology Ultraviolet-visible action spectroscopy Nanotechnology UCTD Currie, Dailin Jade Transformations of nano-enabled products during simulated usage and disposal |
| title | Transformations of nano-enabled products during simulated usage and disposal |
| title_full | Transformations of nano-enabled products during simulated usage and disposal |
| title_fullStr | Transformations of nano-enabled products during simulated usage and disposal |
| title_full_unstemmed | Transformations of nano-enabled products during simulated usage and disposal |
| title_short | Transformations of nano-enabled products during simulated usage and disposal |
| title_sort | transformations of nano enabled products during simulated usage and disposal |
| topic | Nanostructured materials -- Toxicology Ultraviolet-visible action spectroscopy Nanotechnology UCTD |
| url | https://scholar.sun.ac.za/handle/10019.1/128377 |
| work_keys_str_mv | AT curriedailinjade transformationsofnanoenabledproductsduringsimulatedusageanddisposal |