Thesis (MSc)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Water quality analysis forms the basis in assessing and monitoring catchments. As
urban development continuously increase, pollution sources increase in either point
source (wastewater treatment works, industrial effluents) and/or non-point source
origin (storm water discharge, domestic pollutants), accumulating pollutants in the
environment. It was only recently discovered that certain pollutants have subtle
disrupting effects on the endocrine system resulting in health related problems
associated with the reproductive system and thyroid system (growth and
development) of animals and potentially humans. Natural water resource
management proves to include limited biological assays measuring endpoints for
cytoxicity, inflammatory activity and endocrine disruption. The broad objective of
this study was therefore to include several bioassays, not normally used in municipal
(City of Cape Town) monitoring programmes, along with water quality data collected
by the City of Cape Town. The Eerste/Kuils River catchment system, Western Cape,
under the auspices of the City of Cape Town was chosen, and although this catchment
does not contribute to drinking water resources, is subjected to a range of
anthropogenic influences (industrial effluents, household wastewater, agricultural
runoff). Within the short time-frame available for this study (six months) two months,
July (following a dry summer and autumn season) and October (following a wet
winter and early spring season) were selected for water quality monitoring. Spatial
variation (with relevance to specific point and non-point contamination) among
sampling sites were also obtained by choosing several (n=10) along the catchment.
Specific aim of the study therefore included: Firstly (Chapter 2), the use of in vitro
bioassays, lactate-dehydrolises assay (LDH) for cytotoxic activity, pro-inflammatory
hormone Interleukin-6 (IL-6) secretion by human blood cells and a specific
Salmonella ELISA for faecal contamination, in conjunction with routine chemical and
biological (mostly microbiological) monitoring activities. The study indicated
significant variation among sites in all microbiological measures as well in IL-6
secretion and Salmonella presence. Between months, variations were also evident in
certain variables. Secondly (Chapter 3), two bioassays using the yolk precursor
protein, vitellogenin (Vtg) as endpoint was implemented in a) an in vitro Xenopus
laevis liver slice assay (five day exposure) and b) an in vivo Zebrafish (Danio rerio)
bioassay (seven day exposure) assessing estrogenic activity in the Eerste/Kuils River catchment. Although estrogen spiked positive control water samples stimulated Vtg
production in vitro as well as in vivo, no dramatic estrogenic activity was measured at
any of the selected sites. Thirdly (Chapter 4), a bioassay using the thyroid controlled
metamorphosis in Xenopus laevis tadpoles to assess effects on the thyroid hormonal
system was implemented. Thyroid stimulatory activity, compared with a negative
control sample, was measured at two sites along the catchment. Although the
practical implementation of the tadpole semi-static exposure protocol (water
replacement) proved to be labour intensive, all the added bioassays proved to be
valuable tools to add valuable information regarding water quality. It is clear that
more research related to anthropogenic influences along the Eerste/Kuils River
catchment system are needed, specifically in monitoring monthly variations to better
understand annual variation in several of the endpoints studied. / AFRIKAANSE OPSOMMING: Waterkwaliteit vorm die basis vir die evaluering en monitering van opvangsgebiede.
Voortdurende stedelike ontwikkeling gee aanleiding tot ‘n toename in die voorkoms
van besoedelstowwe in die natuurlike omgewing deur gelokaliseerde (punt) bronne
(rioolwerke/industriële uitvloeisel) en/of nie gelokaliseerde (nie punt) bronne (vloed
uitlaat/huishoudelike uitvloeisels) van besoedeling. Dit het onlangs aan die lig gekom
dat van hierdie chemise besoedelstowwe subtiel die endokriene sisteem versteur en so
aanleiding gee tot gesondheidsprobleme in terme van die voortplantingsisteem en
tiroied sisteem (groei en ontwikkeling) by diere en moontlik ook die mens. Daar is
beperkte gebruik van biologiese toetse wat inligting verskaf oor sitotoksiteit,
inflammatoriese aktiwiteit en endokriene versteuring. Die doel van hierdie studie was
dus om van hierdie biologiese toetse, wat normaalweg nie deel uitmaak van die
roetine munisipale (Stad van Kaapstad) opvangsgebied monitering nie, gebruik te
maak. Die Eerste-, Kuilsrivier, Wes Kaap, onder beheer van Stad Kaapstad is gekies
en alhoewel die opvangsgebied nie water bydra tot drinkwaterbronne nie, word die
opvangsgebied beïnvloed deur verskeie mensgemaakte bronne van besoedeling
(afloop vanuit omliggende lanbougebiede). Binne die kort tydsraamwerk van die
projek (ses maande) is besluit om twee maande, Julie (volg ‘n droë somer en herfs
seisoen) en Oktober (volg ‘n nat winter en vroeë lente seisoen) vir water kwaliteit
monitering te kies. Ruimtelike variasie langs die loop van die opvangsgebied is
ingesluit deur moniteringspunte (n=10), met in ag name van die potensiële
besoedelingsbronne. Spesifieke doelwitte van die projek sluit in: Eerstens (Hoofstuk
2), om die in vitro biotoetse, laktaat hidrolise (LDH) vir sitotoksisiteit, proinflammatoriese
hormoon Interleuikin-6 (IL-6) vir inflammatoriese aktiwiteit,
vrygestel deur menslike bloedselle en ‘n Salmonella ELISA vir ontlasting besoedeling
saam met bestaande chemise en biologiese (hoofsaaklik migrobiologiese)
veranderlikes te gebruik. Die studie het getoon dat beduidende variasie in alle
mikrobiologiese toetse asook IL-6 vrystelling en Salmonella voorkoms bestaan het
tussen versamelpunte. Maandelikse variasie in sekere van die veranderlikes het ook
voorgekom. Tweedens (Hoofstuk 3), is twee biotoetse wat die
dooiervoorloperproteïen, vitellogeen (Vtg) as eindpunt gebruik geimplimenteer in a)
‘n in vitro Xenopus laevis lewersnit biotoets (vyf dag blootstelling) en b) ‘n in vivo
Zebravis (Danio rerio) biotoets (sewe dag blootstelling) om estrogenisiteit in die Eerste-, Kuilsrivier opvangsgebied te evalueer. Alhoewel, die estrogeen behandelde
positiewe kontrole water monsters Vtg produksie veroorsaak het in beide die in vitro
lewer-kulture en in vivo vistoets, is geen dramatiess estrogeniese aktiwiteit by enige
van die moniteringspunte gevind nie. Derdens (Hoofstuk 4), is ‘n biotoets wat die
tiroïedbeheerde metamorfose in Xenopus laevis paddavisse gebruik om effekte op die
tiroïedsisteem te evalueer. Die differensiële stimulering (versnelling), in vergelyking
met ‘n negatiewe kontrole watermonster, van die tiroied sisteem is by twee
moniteringspunte in die opvangsgebied waargeneem. Alhoewel die praktiese
implementering van die paddavis semi-statiese (water word gereeld vervang) biotoets
arbeidsintensief is, het alle bykomstige biotoetse waardevolle bykomstige inligting
oor water kwaliteit verskaf wat ‘n belangrike bydrae tot ingeligte bestuursbesluite kan
verleen. Dit is duidelik dat meer navorsing int verband met die menslike invloed
langs die Eerste-, Kuilsrivier opvangsgebied nodig is, veral met maandlikse
monitering vir seisoenale veranderinge.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/20917 |
| Date | 04 1900 |
| Creators | Fourie, Shani |
| Contributors | Van Wyk, J.H., Pool, E.J., Stellenbosch University. Faculty of Agrisciences. Dept. of Conservation Ecology and Entomology. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | xi, 111 leaves : ill. |
| Rights | Stellenbosch University |
Page generated in 0.0061 seconds