Thesis (M.S.Ed.)--Baylor University, 2005. / Includes bibliographical references (p. 64-69).

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>Magister Scientiae - MSc / Water scarcity is becoming an increasingly relevant problem for urban centres, especially in Southern Africa. However, water availability is not the only concern for consumers, because water quality is just as relevant. Many studies have revealed adverse health effects in organisms exposed to polluted waters, and the main source of that water pollution was traced back to sewage treatment works (STWs). Physiological systems that are affected include the endocrine system (as well as the reproductive system) and the immune system. Recently, the Stellenbosch STW started upgrading its facility, but this procedure would also affect the STW‘s operations. Stellenbosch STW uses an activated sludge treatment, but also employs trickling filters (biofilters). After screening and grit removal, wastewater enters trickling filters, and then undergoes activated sludge treatment (aerobic basin). After activated sludge treatment (and settling) some water is chlorinated before entering a maturation pond. The other water goes directly to a larger maturation pond (for a longer period), instead. The final effluent then gets discharged into the Veldwagters River. Since STW operations is an important factor in STW effluent quality, this study aimed to investigate the water quality (at Stellenbosch STW) during the upgrade. Specifically, the bacterial quality, the steroidal quality (testosterone, progesterone, estrone: E1, 17 β- estradiol: E2 and 17 α-ethinyl estradiol: EE2) and the potential immunotoxic quality of waters were assessed. Water samples were collected after the grit removal (influent), after the trickling filters (biofilter effluent), while it was leaving the aerobic basin activated sludge effluent) and as it was leaving the maturation ponds (final effluent). To determine bacterial quality a semi-quantitative ReadyCult® assay was performed on raw water samples (detects total coliforms and Escherichia coli). Bacterial levels were high for all influent samples, water from the biofilter, water from the aerobic digester (activated sludge) and the final effluent (most days). The first collection date, however, showed less than 1cfu/mL of both E. coli and total coliforms for the final effluent. Raw water also underwent solid phase extraction, before the steroid concentrations were determined by enzyme-linked immunosorbent assays (ELISAs). Steroid levels were very high in the influent. Each treatment progressively reduced the steroid concentration. However, progesterone concentration increased during the biofilter treatment. The increase in progesterone was probably due to bacterial de-conjugation of hydrophilic-progesterone-conjugates. Nonetheless effluent steroid levels were significantly lower than the influent. Steroid reduction through the Stellenbosch STW was 96%, 95%, 55%, 78% and 87% for testosterone, progesterone, estrone, estradiol and ethinyl estradiol respectively. Much variability in steroid concentrations was noted between sampling dates. The activated sludge treatment was the best at reducing steroid concentration. Nonetheless, the STW still discharged steroids into the environment. Finally, the humoral immune effects of Stellenbosch STW influent and effluent was determined by using hybridoma cells and assessing affects on antibody production. Antibody levels were then detected by ELISA. No adverse effects to antibody synthesis/secretion were noted as a result of exposure to either influent or effluent.

To determine if known androgenic hormone precursors for testosterone in the androgen pathway would be readily transformed to testosterone, eight male subjects [mean age 23.8 (SEM 3) years, bodymass 83.1 (SEM 8.7) kg, height 175.6 (SEM 8.5) cm] underwent a randomized, double-blind, cross-over, placebo-controlled oral treatment with 200 mg of 4-androstene-3,17-dione (Δ4), 4-androstene-3β,17β-diol (Δ4Diol), and placebo (PL). The periods of study were separated by 7 days of washout. Blood was drawn at baseline and subsequently every 30 min for 90 min after treatment. Analysis revealed mean area-under-the-curve (AUC) serum Δ4 concentrations to be higher during Δ4 treatment [2177 (SEM 100) nmol.l-1] than Δ4Diol [900 (SEM 96) nmol.l-1] or PL [484 (SEM 82) nmol.l-1; P < 0.0001]. The Δ4 treatment also revealed a significant effect on total testosterone with a mean AUC [1632.5 (SEM 121) nmol.l-1] that was greater than PL [1418.5 (SEM 131) nmol.l-1; P < 0.05] but not significantly different from those observed after Δ4Diol treatment [1602.9 (SEM 119) nmol.l-1; P = 0.77]. Free testosterone concentrations followed a similar pattern where mean AUC for the Δ4 treatment [6114.0 (SEM 600) pmol.l-1] was greater than after PL [4974.6 (SEM 565) pmol.l-1; P < 0.06] but not significantly different from those observed after Δ4Diol [5632.0 (SEM 389) pmol.l-1; P = 0.48]. The appearance and apparent conversion to total and free testosterone over 90 min was stronger for the Δ4 treatment (r = 0.91, P < 0.045) than for Δ4Diol treatment (r = 0.69, NS) and negatively correlated for PL (r = -0.90, P < 0.02). These results would suggest that Δ4, and perhaps Δ4Diol, taken by month are capable of producing in vivo increases in testosterone concentrations in apparently healthy young men as has already been observed in women after treatment with Δ4.

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Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 4 uppsatser.

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