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Pharmaceuticals are emerging surface water contaminants, and are manufactured, used, and released into environment in considerable amounts. Concerns have been raised due to the inherent potency and bioactivity of these molecules, which makes effects at low concentrations more likely. The ubiquitous presence and stability of pharmaceuticals brings up concerns about the frequency and length of exposures. However, the distribution and fate of these compounds in surface water bodies is not clear. There is limited information about the potential effects in non-target, especially aquatic, species vulnerable to cumulative or lifelong exposures. Carbamazepine (CBZ) and gemfibrozil (GEM) are two of the most frequently detected pharmaceuticals in surface water. This thesis examined sub-lethal adverse reproductive effects of chronic direct exposure of CBZ and GEM to F0 zebrafish and several generations of unexposed offspring; the effects of exposure on testicular steroidogenesis were also examined. Chronic exposure of zebrafish to CBZ and GEM reduced ex vivo production of 11KT in testes. In vivo, CBZ decreased reproductive output, 11-ketotestosterone (11KT), male courtship and aggression behaviours, and sperm morphology in F0 parents. The F1, F2 and F3 offspring of CBZ exposed males had lower reproductive output, altered courtship, aggression, sperm morphology and lower 11KT compared to fish from the unexposed lineage. The adverse effects persisted into the F3 generation which suggested transgenerational paternal effects. GEM decreased reproductive output in F0 parents and a reduction in 11KT, altered male courtship, aggression and sperm morphology. Unexposed F1 male offspring, but not other generations, had sub-lethal toxic effects from parental exposure. We therefore suggest that CBZ and GEM act as endocrine disruptors in fish and that chronic exposure may reduce male reproductive fitness. / Dissertation / Doctor of Philosophy (PhD) / Human pharmaceuticals reach aquatic environments through municipal wastewater. The bioactivity of pharmaceuticals at low concentrations has raised concerns about undesired effects in aquatic species like fish, which can experience chronic exposures. This thesis examined adverse reproductive effects of direct chronic exposure of carbamazepine and gemfibrozil to parental zebrafish and their un-exposed offspring for multiple generations. Exposure to both compounds reduced androgens and reproduction and altered behaviour, and sperm quality in males. Effects persisted in the unexposed offspring. Parental carbamazepine exposure impacted multiple generations. We suggest that carbamazepine and gemfibrozil may reduce male reproductive fitness by reducing male sex steroids.

FUNDAMENTO: O suco de laranja (Citrus sinensis) é rico em vitami-na C, folatos e seu principal flavonóide, a hesperidina, cuja conformação es-pacial é semelhante à genisteína de soja que tem ação favorável sobre o aparelho cardiovascular. A vitamina C é conhecida como potente inibidor da peroxidação lipídica. Mas sua capacidade por possuir efeitos terapêuticos no tratamento da aterosclerose é pouco estudada. OBJETIVO: O presente tra-balho visa a determinar se o suco de laranja pode ter efeito aditivo no trata-mento com estatinas e fibratos, reduzindo placas ateroscleróticas e a quanti-dade de LDL Oxidado (LDL ox). MÉTODOS: Análise do efeito do suco nas dimensões de cortes histológicos e na quantidade de anticorpos anti LDL oxidado (antiLDLox) em lesões ateroscleróticas na aorta de coelhos. RE-SULTADOS: O suco de laranja potencializou a redução de área de placas ateroscleróticas e a quantidade de LDL(ox) em relação às reduções obtidas com rosuvastatina e gemfibrozil. CONCLUSÕES: O suco de laranja tem efei-to sinérgico ao tratamento convencional da aterosclerose de coelhos / Statins and fibrates have been used as anti-atherosclerotic drugs. However, a high number of treated patients still present acute events and death by atherosclerotic complications. Flavonoid ingestion has been associ-ated with lower risk of death, lower incidence of coronary artery disease and more preserved endothelial function in atherosclerotic patients. Orange juice is rich in C vitamine, a well known potent inhibitor of lipidic peroxidation, and in flavonoids, mainly the hesperidine that seems the soy bean genisteine, which is associated with decrease LDL and increase HDL. Objective: In this work we studied if orange juice has addictive effect to statin and gemfibrozil in the treatment of rabbit atherosclerosis, reducing plaque area and oxidate LDL (LDLox). Methods: Five group of atherosclerotic rabbits, fed with 1% cholesterol enriched diet during 12 weeks, were analyzed: GI - received no treatment, GII Gemfibrozil 600mg/day, GIII treated with Gemfibrozil 600mg/day + orange juice, GIV - rosuvastatin/10mg / day and GV - rosu-vastatin/10mg / day + orange juice. The most severe atherosclerotic cross section in ascendant aorta was analyzed in H&E and anti-oxidated LDL (oxLDL) immunostained slides, obtaining intimal area, total vessel area, % luminal obstruction and % oxLDL area in intima. Results: The means (stan-dard deviations) of plaque area and % plaque area of oxLDL in GI were 1.05 (0.91) and 0.12 (0.13), with no significant difference with GII animals, respec- tively 3.85 (5.27) and 0.18 (0.22), but significantly reduced in GIII, 0.64 (1.56) and 0.03 (0.05). Similar data were seen in GIV, 2.11 (2.77) and 0.19 (0.25), compared with GV, 0.04 (0.09) and 0.00 (0.00). Conclusion: This work de-monstrates that orange juice has a potential synergistic action with statin and fibrates in reducing atherosclerosis and the mechanism seems to involve in-hibition of oxLDL concentration and migration of smooth muscle cells in the subendothelial space

A bench-scale study of the degradation of four selected pharmaceuticals and personal care products (PPCPs) was carried out using UV and UV/H₂O₂ treatment employing low pressure (LP) and medium pressure (MP) lamps. The target substances included the pharmaceutical compounds ibuprofen, naproxen, and gemfibrozil, along with the bactericide triclosan. There were four main objectives of the study, as follows: to evaluate the removal of the target compounds using UV irradiation alone and UV/H₂O₂, to determine the reaction kinetics for direct and indirect photolysis of each selected compound, to determine the influence of major water quality parameters on the efficacy of treatment, and to compare the applied UV and UV/H₂O₂ doses to those that have been found to be effective for disinfection and removal of taste and odour compounds, respectively. For initial ultra-pure water experiments the target compounds were spiked at concentrations of approximately 250 µg/L (~1 µM). In latter ultra-pure water experiments and in the partially-treated water experiments, the selected PPCPs were spiked at a lower range (c~500-1000 ng/L), which is more representative of reported environmental concentrations. In an ultra-pure water matrix, a high LP fluence of 1000 mJ/cm² caused only triclosan to substantially degrade. Furthermore, with LP-UV/H₂O₂ only triclosan and naproxen had average percent removals above 60% at a typical disinfection fluence of 40 mJ/cm² with 100 mg/L H₂O₂. Complete degradation of all four compounds in ultra-pure water was achieved with very high fluences (compared to those used for UV disinfection) with MP-UV alone (at or above 1000 mJ/cm²) or with relatively high fluences for MP-UV/H₂O₂ (200-300 mJ/cm²) with 10 mg/L H₂O₂. Overall, when compared at similar applied fluences, the MP lamp was much more effective than the LP lamp. Furthermore, the addition of H₂O₂ typically increased removal rates, in some cases substantially, through formation and subsequent reaction of the PPCP with the •OH radical. When target substances were treated all together in an ultra-pure water solution, removals were lower than when they were treated independently at the same individual concentrations (~250 µg/L) this may simply have been the result of a higher total contaminant concentration in solution, which lessened the availability of the •OH radical and incident UV irradiation for degradation of all compounds. On the other hand, removals were improved when the combined target compounds were present at a lower individual concentration range (~750 ng/L), which suggests that removals may be concentration driven, with reduced matrix effects seen at lower overall contaminant concentrations. Furthermore, during the partially-treated water experiments, variability in treatment performance was observed with differing water quality; however, it was not evident which specific quality parameters influenced treatment effectiveness. On the other hand, substantial and sometimes complete, degradation of the target compounds was still seen in the partially-treated water with high MP-UV/H₂O₂ doses (e.g. 300 mJ/cm² + 10 mg/L H₂O₂ and 500 + 10 mg/L H₂O₂). For the kinetic experiments, compounds were spiked individually in ultra-pure water (c~250 µg/L = ~1µM). The photolysis of the target compounds during treatment was assumed to be a pseudo-first-order reaction. Kinetic parameters were determined for both direct and indirect photolysis for both lamps. The calculated rate constants confirmed the importance of •OH radicals for degradation of these compounds, especially for ibuprofen and gemfibrozil. For ibuprofen and gemfibrozil, direct photolysis rate constants could not be determined for LP-UV because very little degradation was seen at the fluences tested. LP-UV direct phototlysis rate constants for naproxen and triclosan were 0.0002 and 0.0033 cm²/mJ, respectively. Overall rate constants describing degradation of the four compounds due to LP-UV/H₂O₂ ranged from 0.0049 to 0.0124 cm²/mJ. All four compounds had fluence-based reaction rate constants for MP-UV indirect photolysis of approximately 0.01 cm²/mJ, while MP-UV direct photolysis rate constants ranged between 0.0007-0.007 cm²/mJ, with ibuprofen having the lowest and triclosan the highest. The overall trends were similar to those seen by other researchers for the removal of taste and odour compounds. For example, fluences required for substantial removal were much higher than typical disinfection doses, the MP lamp was more effective than the LP lamp (when compared solely on a fluence-basis), and the addition of H₂O₂ improved removals. On the whole, UV/H₂O₂ appears to be a very promising technology for the removal of these selected PPCPs during drinking water treatment, and is likely to be equally effective for other, similar contaminants.

A bench-scale study of the degradation of four selected pharmaceuticals and personal care products (PPCPs) was carried out using UV and UV/H₂O₂ treatment employing low pressure (LP) and medium pressure (MP) lamps. The target substances included the pharmaceutical compounds ibuprofen, naproxen, and gemfibrozil, along with the bactericide triclosan. There were four main objectives of the study, as follows: to evaluate the removal of the target compounds using UV irradiation alone and UV/H₂O₂, to determine the reaction kinetics for direct and indirect photolysis of each selected compound, to determine the influence of major water quality parameters on the efficacy of treatment, and to compare the applied UV and UV/H₂O₂ doses to those that have been found to be effective for disinfection and removal of taste and odour compounds, respectively. For initial ultra-pure water experiments the target compounds were spiked at concentrations of approximately 250 µg/L (~1 µM). In latter ultra-pure water experiments and in the partially-treated water experiments, the selected PPCPs were spiked at a lower range (c~500-1000 ng/L), which is more representative of reported environmental concentrations. In an ultra-pure water matrix, a high LP fluence of 1000 mJ/cm² caused only triclosan to substantially degrade. Furthermore, with LP-UV/H₂O₂ only triclosan and naproxen had average percent removals above 60% at a typical disinfection fluence of 40 mJ/cm² with 100 mg/L H₂O₂. Complete degradation of all four compounds in ultra-pure water was achieved with very high fluences (compared to those used for UV disinfection) with MP-UV alone (at or above 1000 mJ/cm²) or with relatively high fluences for MP-UV/H₂O₂ (200-300 mJ/cm²) with 10 mg/L H₂O₂. Overall, when compared at similar applied fluences, the MP lamp was much more effective than the LP lamp. Furthermore, the addition of H₂O₂ typically increased removal rates, in some cases substantially, through formation and subsequent reaction of the PPCP with the •OH radical. When target substances were treated all together in an ultra-pure water solution, removals were lower than when they were treated independently at the same individual concentrations (~250 µg/L) this may simply have been the result of a higher total contaminant concentration in solution, which lessened the availability of the •OH radical and incident UV irradiation for degradation of all compounds. On the other hand, removals were improved when the combined target compounds were present at a lower individual concentration range (~750 ng/L), which suggests that removals may be concentration driven, with reduced matrix effects seen at lower overall contaminant concentrations. Furthermore, during the partially-treated water experiments, variability in treatment performance was observed with differing water quality; however, it was not evident which specific quality parameters influenced treatment effectiveness. On the other hand, substantial and sometimes complete, degradation of the target compounds was still seen in the partially-treated water with high MP-UV/H₂O₂ doses (e.g. 300 mJ/cm² + 10 mg/L H₂O₂ and 500 + 10 mg/L H₂O₂). For the kinetic experiments, compounds were spiked individually in ultra-pure water (c~250 µg/L = ~1µM). The photolysis of the target compounds during treatment was assumed to be a pseudo-first-order reaction. Kinetic parameters were determined for both direct and indirect photolysis for both lamps. The calculated rate constants confirmed the importance of •OH radicals for degradation of these compounds, especially for ibuprofen and gemfibrozil. For ibuprofen and gemfibrozil, direct photolysis rate constants could not be determined for LP-UV because very little degradation was seen at the fluences tested. LP-UV direct phototlysis rate constants for naproxen and triclosan were 0.0002 and 0.0033 cm²/mJ, respectively. Overall rate constants describing degradation of the four compounds due to LP-UV/H₂O₂ ranged from 0.0049 to 0.0124 cm²/mJ. All four compounds had fluence-based reaction rate constants for MP-UV indirect photolysis of approximately 0.01 cm²/mJ, while MP-UV direct photolysis rate constants ranged between 0.0007-0.007 cm²/mJ, with ibuprofen having the lowest and triclosan the highest. The overall trends were similar to those seen by other researchers for the removal of taste and odour compounds. For example, fluences required for substantial removal were much higher than typical disinfection doses, the MP lamp was more effective than the LP lamp (when compared solely on a fluence-basis), and the addition of H₂O₂ improved removals. On the whole, UV/H₂O₂ appears to be a very promising technology for the removal of these selected PPCPs during drinking water treatment, and is likely to be equally effective for other, similar contaminants.

A bench-scale study of the degradation of four selected pharmaceuticals and personal care products (PPCPs) was carried out using UV and UV/H₂O₂ treatment employing low pressure (LP) and medium pressure (MP) lamps. The target substances included the pharmaceutical compounds ibuprofen, naproxen, and gemfibrozil, along with the bactericide triclosan. There were four main objectives of the study, as follows: to evaluate the removal of the target compounds using UV irradiation alone and UV/H₂O₂, to determine the reaction kinetics for direct and indirect photolysis of each selected compound, to determine the influence of major water quality parameters on the efficacy of treatment, and to compare the applied UV and UV/H₂O₂ doses to those that have been found to be effective for disinfection and removal of taste and odour compounds, respectively. For initial ultra-pure water experiments the target compounds were spiked at concentrations of approximately 250 µg/L (~1 µM). In latter ultra-pure water experiments and in the partially-treated water experiments, the selected PPCPs were spiked at a lower range (c~500-1000 ng/L), which is more representative of reported environmental concentrations. In an ultra-pure water matrix, a high LP fluence of 1000 mJ/cm² caused only triclosan to substantially degrade. Furthermore, with LP-UV/H₂O₂ only triclosan and naproxen had average percent removals above 60% at a typical disinfection fluence of 40 mJ/cm² with 100 mg/L H₂O₂. Complete degradation of all four compounds in ultra-pure water was achieved with very high fluences (compared to those used for UV disinfection) with MP-UV alone (at or above 1000 mJ/cm²) or with relatively high fluences for MP-UV/H₂O₂ (200-300 mJ/cm²) with 10 mg/L H₂O₂. Overall, when compared at similar applied fluences, the MP lamp was much more effective than the LP lamp. Furthermore, the addition of H₂O₂ typically increased removal rates, in some cases substantially, through formation and subsequent reaction of the PPCP with the •OH radical. When target substances were treated all together in an ultra-pure water solution, removals were lower than when they were treated independently at the same individual concentrations (~250 µg/L) this may simply have been the result of a higher total contaminant concentration in solution, which lessened the availability of the •OH radical and incident UV irradiation for degradation of all compounds. On the other hand, removals were improved when the combined target compounds were present at a lower individual concentration range (~750 ng/L), which suggests that removals may be concentration driven, with reduced matrix effects seen at lower overall contaminant concentrations. Furthermore, during the partially-treated water experiments, variability in treatment performance was observed with differing water quality; however, it was not evident which specific quality parameters influenced treatment effectiveness. On the other hand, substantial and sometimes complete, degradation of the target compounds was still seen in the partially-treated water with high MP-UV/H₂O₂ doses (e.g. 300 mJ/cm² + 10 mg/L H₂O₂ and 500 + 10 mg/L H₂O₂). For the kinetic experiments, compounds were spiked individually in ultra-pure water (c~250 µg/L = ~1µM). The photolysis of the target compounds during treatment was assumed to be a pseudo-first-order reaction. Kinetic parameters were determined for both direct and indirect photolysis for both lamps. The calculated rate constants confirmed the importance of •OH radicals for degradation of these compounds, especially for ibuprofen and gemfibrozil. For ibuprofen and gemfibrozil, direct photolysis rate constants could not be determined for LP-UV because very little degradation was seen at the fluences tested. LP-UV direct phototlysis rate constants for naproxen and triclosan were 0.0002 and 0.0033 cm²/mJ, respectively. Overall rate constants describing degradation of the four compounds due to LP-UV/H₂O₂ ranged from 0.0049 to 0.0124 cm²/mJ. All four compounds had fluence-based reaction rate constants for MP-UV indirect photolysis of approximately 0.01 cm²/mJ, while MP-UV direct photolysis rate constants ranged between 0.0007-0.007 cm²/mJ, with ibuprofen having the lowest and triclosan the highest. The overall trends were similar to those seen by other researchers for the removal of taste and odour compounds. For example, fluences required for substantial removal were much higher than typical disinfection doses, the MP lamp was more effective than the LP lamp (when compared solely on a fluence-basis), and the addition of H₂O₂ improved removals. On the whole, UV/H₂O₂ appears to be a very promising technology for the removal of these selected PPCPs during drinking water treatment, and is likely to be equally effective for other, similar contaminants.

A bench-scale study of the degradation of four selected pharmaceuticals and personal care products (PPCPs) was carried out using UV and UV/H₂O₂ treatment employing low pressure (LP) and medium pressure (MP) lamps. The target substances included the pharmaceutical compounds ibuprofen, naproxen, and gemfibrozil, along with the bactericide triclosan. There were four main objectives of the study, as follows: to evaluate the removal of the target compounds using UV irradiation alone and UV/H₂O₂, to determine the reaction kinetics for direct and indirect photolysis of each selected compound, to determine the influence of major water quality parameters on the efficacy of treatment, and to compare the applied UV and UV/H₂O₂ doses to those that have been found to be effective for disinfection and removal of taste and odour compounds, respectively. For initial ultra-pure water experiments the target compounds were spiked at concentrations of approximately 250 µg/L (~1 µM). In latter ultra-pure water experiments and in the partially-treated water experiments, the selected PPCPs were spiked at a lower range (c~500-1000 ng/L), which is more representative of reported environmental concentrations. In an ultra-pure water matrix, a high LP fluence of 1000 mJ/cm² caused only triclosan to substantially degrade. Furthermore, with LP-UV/H₂O₂ only triclosan and naproxen had average percent removals above 60% at a typical disinfection fluence of 40 mJ/cm² with 100 mg/L H₂O₂. Complete degradation of all four compounds in ultra-pure water was achieved with very high fluences (compared to those used for UV disinfection) with MP-UV alone (at or above 1000 mJ/cm²) or with relatively high fluences for MP-UV/H₂O₂ (200-300 mJ/cm²) with 10 mg/L H₂O₂. Overall, when compared at similar applied fluences, the MP lamp was much more effective than the LP lamp. Furthermore, the addition of H₂O₂ typically increased removal rates, in some cases substantially, through formation and subsequent reaction of the PPCP with the •OH radical. When target substances were treated all together in an ultra-pure water solution, removals were lower than when they were treated independently at the same individual concentrations (~250 µg/L) this may simply have been the result of a higher total contaminant concentration in solution, which lessened the availability of the •OH radical and incident UV irradiation for degradation of all compounds. On the other hand, removals were improved when the combined target compounds were present at a lower individual concentration range (~750 ng/L), which suggests that removals may be concentration driven, with reduced matrix effects seen at lower overall contaminant concentrations. Furthermore, during the partially-treated water experiments, variability in treatment performance was observed with differing water quality; however, it was not evident which specific quality parameters influenced treatment effectiveness. On the other hand, substantial and sometimes complete, degradation of the target compounds was still seen in the partially-treated water with high MP-UV/H₂O₂ doses (e.g. 300 mJ/cm² + 10 mg/L H₂O₂ and 500 + 10 mg/L H₂O₂). For the kinetic experiments, compounds were spiked individually in ultra-pure water (c~250 µg/L = ~1µM). The photolysis of the target compounds during treatment was assumed to be a pseudo-first-order reaction. Kinetic parameters were determined for both direct and indirect photolysis for both lamps. The calculated rate constants confirmed the importance of •OH radicals for degradation of these compounds, especially for ibuprofen and gemfibrozil. For ibuprofen and gemfibrozil, direct photolysis rate constants could not be determined for LP-UV because very little degradation was seen at the fluences tested. LP-UV direct phototlysis rate constants for naproxen and triclosan were 0.0002 and 0.0033 cm²/mJ, respectively. Overall rate constants describing degradation of the four compounds due to LP-UV/H₂O₂ ranged from 0.0049 to 0.0124 cm²/mJ. All four compounds had fluence-based reaction rate constants for MP-UV indirect photolysis of approximately 0.01 cm²/mJ, while MP-UV direct photolysis rate constants ranged between 0.0007-0.007 cm²/mJ, with ibuprofen having the lowest and triclosan the highest. The overall trends were similar to those seen by other researchers for the removal of taste and odour compounds. For example, fluences required for substantial removal were much higher than typical disinfection doses, the MP lamp was more effective than the LP lamp (when compared solely on a fluence-basis), and the addition of H₂O₂ improved removals. On the whole, UV/H₂O₂ appears to be a very promising technology for the removal of these selected PPCPs during drinking water treatment, and is likely to be equally effective for other, similar contaminants.

FUNDAMENTO: O suco de laranja (Citrus sinensis) é rico em vitami-na C, folatos e seu principal flavonóide, a hesperidina, cuja conformação es-pacial é semelhante à genisteína de soja que tem ação favorável sobre o aparelho cardiovascular. A vitamina C é conhecida como potente inibidor da peroxidação lipídica. Mas sua capacidade por possuir efeitos terapêuticos no tratamento da aterosclerose é pouco estudada. OBJETIVO: O presente tra-balho visa a determinar se o suco de laranja pode ter efeito aditivo no trata-mento com estatinas e fibratos, reduzindo placas ateroscleróticas e a quanti-dade de LDL Oxidado (LDL ox). MÉTODOS: Análise do efeito do suco nas dimensões de cortes histológicos e na quantidade de anticorpos anti LDL oxidado (antiLDLox) em lesões ateroscleróticas na aorta de coelhos. RE-SULTADOS: O suco de laranja potencializou a redução de área de placas ateroscleróticas e a quantidade de LDL(ox) em relação às reduções obtidas com rosuvastatina e gemfibrozil. CONCLUSÕES: O suco de laranja tem efei-to sinérgico ao tratamento convencional da aterosclerose de coelhos / Statins and fibrates have been used as anti-atherosclerotic drugs. However, a high number of treated patients still present acute events and death by atherosclerotic complications. Flavonoid ingestion has been associ-ated with lower risk of death, lower incidence of coronary artery disease and more preserved endothelial function in atherosclerotic patients. Orange juice is rich in C vitamine, a well known potent inhibitor of lipidic peroxidation, and in flavonoids, mainly the hesperidine that seems the soy bean genisteine, which is associated with decrease LDL and increase HDL. Objective: In this work we studied if orange juice has addictive effect to statin and gemfibrozil in the treatment of rabbit atherosclerosis, reducing plaque area and oxidate LDL (LDLox). Methods: Five group of atherosclerotic rabbits, fed with 1% cholesterol enriched diet during 12 weeks, were analyzed: GI - received no treatment, GII Gemfibrozil 600mg/day, GIII treated with Gemfibrozil 600mg/day + orange juice, GIV - rosuvastatin/10mg / day and GV - rosu-vastatin/10mg / day + orange juice. The most severe atherosclerotic cross section in ascendant aorta was analyzed in H&E and anti-oxidated LDL (oxLDL) immunostained slides, obtaining intimal area, total vessel area, % luminal obstruction and % oxLDL area in intima. Results: The means (stan-dard deviations) of plaque area and % plaque area of oxLDL in GI were 1.05 (0.91) and 0.12 (0.13), with no significant difference with GII animals, respec- tively 3.85 (5.27) and 0.18 (0.22), but significantly reduced in GIII, 0.64 (1.56) and 0.03 (0.05). Similar data were seen in GIV, 2.11 (2.77) and 0.19 (0.25), compared with GV, 0.04 (0.09) and 0.00 (0.00). Conclusion: This work de-monstrates that orange juice has a potential synergistic action with statin and fibrates in reducing atherosclerosis and the mechanism seems to involve in-hibition of oxLDL concentration and migration of smooth muscle cells in the subendothelial space

The presence of pharmaceuticals and personal care products (PPCPs) in the aquatic environment has been a growing issue of concern over the past twenty years. Compounds from various pharmaceutical classes have been detected at ng to µg L-1 concentrations in waste water effluent, surface, ground and drinking water. Although the concentrations required for these compounds to elicit a therapeutic response is higher than what is detected in the aquatic environment, the impacts pharmaceuticals may have on aquatic species under chronic or mixture conditions remains largely unknown. This thesis addresses this knowledge gap by evaluating the impacts of chronic exposure to four frequently detected pharmaceuticals and pharmaceutical mixtures on the physiology of the model teleost, zebrafish (Danio rerio). Environmentally relevant concentrations of acetaminophen, carbamazepine, gemfibrozil and venlafaxine significantly reduced zebrafish fecundity and increased embryonic mortality. Pharmaceutical exposure to gemfibrozil and carbamazepine altered the structural morphology of the ovary; all compounds tested altered kidney histology. As exposure in the environment is rarely ever to a single compound, animals were exposed to a quaternary mixture of the four compounds and wastewater effluent. Under mixture conditions, reproductive, developmental and histological effects were also observed, however they generally were more severe then those seen with single compound exposure. Overall, these results showed that chronic, low dose pharmaceutical exposure were sufficient to induce a suite of physiological effects suggesting an overall decrease in fish health. Effects on offspring after chronic parental exposure to gemfibrozil and carbamazepine resulted in alterations in male breeding behaviour, reduced fecundity, decreased sperm velocity and induced morphological changes to spermatozoa. These novel findings expand the limited knowledge base of studies examining effects on offspring. Lastly, acetaminophen was confirmed to elicit its developmental impacts in fish via the cyclooxygenase pathway; the same mechanism of action as observed in mammals. This thesis has made significant contributions to identifying the physiological consequences of environmental pharmaceutical toxicity to fish. / Thesis / Candidate in Philosophy

Cell replication and division are central to the proliferation of life, and have implications for normal growth and development as well as disease state. Assembly of a complete picture of the systems which control this process requires identification of individual genetic components, but the identity and complete sequence of events that trigger initiation of cell division, at a point called START in yeast, remain unknown. Here, we evaluated panels of non-essential single gene deletion strains and tested the effects of FDA-approved drugs on cell-cycle progression, using flow cytometry to detect altered DNA content. Previous studies relied mainly on cell size changes to systematically identify genes required for the timely completion of START. This analysis revealed that most gene deletions that altered cell-cycle progression did not change cell size. Our results highlight a strong requirement for ribosomal biogenesis and protein synthesis for initiation of cell division. We also identified numerous factors that have not been previously implicated in cell-cycle control mechanisms. We found that cystathionine-beta-synthase (CBS) advances START in two ways: by promoting cell growth, which requires CBS's catalytic activity, and by a separate function which does not require that activity. CBS defects cause disease in humans, and in animals CBS has vital, non-catalytic, unknown roles. Hence, our results may be relevant for human biology. Screening chemical libraries to identify compounds that affect overall cell proliferation is common. However, it is generally not known whether the compounds tested alter the timing of particular cell-cycle transitions. Our approach revealed strong cell-cycle effects of several commonly used pharmaceuticals. We show that the antilipemic gemfibrozil delays initiation of DNA replication, while cells treated with the antidepressant fluoxetine severely delay progression through mitosis. We discovered a strong suppressive interaction between gemfibrozil and fluoxetine. The novel interaction between gemfibrozil and fluoxetine suggests that identifying and combining drugs that show cell-cycle effects might streamline identification of drug combinations with a pronounced impact on cell proliferation. Our studies not only transform our view of START, but also expand the repertoire of genetic and chemical means to modulate the eukaryotic cell cycle.