Endocrine disrupting chemicals (EDCs) are a group of synthetic and natural chemicals that have the potential to mimic the hormone-like activities in the human body. This study was conducted to recognize whether recycled water (a source of EDCs) has the potential to contaminate the environment when such water is used for irrigation purposes. Batch sorption and miscible displacement experiments were conducted to elucidate the fate and transport of four EDCs including estrone, 17β estradiol, octylphenol and nonylphenol in a soil from Hawaii. The sorption capacity of the soil from two depths (2 ft as topsoil and 15 ft as saprolite) was estimated using recycled water and deionized water as the mobile phases. The transport parameters of these contaminants were obtained by using the inverse modeling approaches as provided in the HYDRUS 1D code. All four EDCs sorbed significantly on the soil. Octylphenol and Nonylphenol rapidly degraded during sorption. The Freundlich model was suitable to describe the sorption isotherm. The sorption nonlinearity was relatively higher for saprolite compared to topsoil. Both physical and chemical non-equilibrium processes were found to affect the mobility of the EDCs in the soil. The migration of EDCs in the soil was enhanced in recycled water due to the presence of dissolved organic carbon and elevated salt concentration. The ambient pH had little effect on sorption of EDCs on the soil from either depth.

Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xviii, 168 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.

Thesis (PH.D.)--Michigan State University. Biochemistry and Molecular Biology, 2008. / Title from PDF t.p. (viewed on Aug. 11, 2009) Includes bibliographical references. Also issued in print.

Thesis (M.S.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains vi, 44 p. : ill. (some col.), map. Includes abstract. Includes bibliographical references (p. 28-35).

Endocrine disrupting compounds (EDC) are environmental contaminants that disrupt reproduction, development and behaviour in aquatic organisms. A thorough evaluation of the impacts of EDCs on aquatic organisms is currently limited by a lack of robust biomarkers in small model fish, particularly for assessing EDCs with (anti-)androgenic activity. Male sticklebacks build nests using spiggin, an androgen-responsive glycoprotein, which can be used to assess (anti-)androgenic exposure. EDC assessment in the field using threespine stickleback and the spiggin biomarker is limited to coastal and estuarine environments. However, their freshwater relative, brook stickleback (Culaea inconstans), also possess spiggin and their widespread distribution suggests that they may have applications as a bioindicator of EDCs in freshwater systems. Therefore, the overall objective of this thesis was to determine if brook stickleback are a suitable bioindicator species for EDCs by evaluating their response and sensitivity to estrogenic and (anti-)androgenic chemicals. Basal transcript levels of spiggin in kidney and vitellogenin in liver were first measured in wild-caught brook stickleback using qPCR and found to be differentially expressed in males and females. Brook stickleback were then exposed to two model compounds, 17α-ethinylestradiol (EE2) and 17α-methyltestosterone (MT), at 1, 10 and 100 ng/L for 21 days (sampled at 7 and 21 days) via static-renewal to determine the responsiveness of these transcripts to exogenous hormones. The effect of hormone exposure on condition factor, organosomatic indices and histopathology of kidneys was also measured. Exposure to MT and EE2 significantly induced spiggin and vitellogenin transcripts in female kidneys and male livers, respectively. Exposure to EE2 also significantly increased the hepatosomatic index in females after 7 days and in both sexes after 21 days whereas the gonadosomatic index was reduced in females after 21 days. An increase in kidney epithelium cell height was also observed in MT-exposed females and males after 7 days. These results mirror those of threespine stickleback and suggest that brook stickleback are responsive to androgenic and estrogenic chemical exposure and more specifically, possess quantifiable and sensitive biomarkers for exposure to compounds with androgenic activity. In a third experiment, female fish were co-exposed to MT at 500 ng/L and an anti-androgen (flutamide; FL) at 25, 150 and 250 µg/L for 14 days (sampled at 4 and 14 days) to validate this bioassay for the evaluation of anti-androgens using the same endpoints as in the previous two experiments. In females, exposure to MT increased spiggin transcript levels and nephrosomatic index (NSI) but co-exposure to FL did not result in a significant suppression of these endpoints because of high inter-individual variability. In males, exposure to MT increased NSI and co-exposure to FL resulted in a reduction in this endpoint, illustrating anti-androgenic effects. Although the response of brook stickleback to hormone exposure was endpoint-specific and was at times lower than other small model fish species, the ability to simultaneously assess estrogenic and (anti-)androgenic chemical exposure in a single fish using quantitative endpoints is an advantage exclusively held by members of the stickleback family. The results of this thesis suggest that brook stickleback hold promise as an additional small fish model for the evaluation of EDCs, with potential application in EDC biomonitoring in the freshwaters of North America.

Made available in DSpace on 2015-05-14T16:53:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-11-20Bitstream added on 2015-05-14T16:59:05Z : No. of bitstreams: 1 000824366.pdf: 8069156 bytes, checksum: fb88188a8191b11bf5177ffde32fe389 (MD5) / Desruptoress endócrinos (D.E), como por exemplo, os pesticidas, representam uma classe emergente de contaminantes em sistemas aquáticos, que pode comprometer a vida da biota aquática e de seres humanos. Embora alguns estudos estejam sendo desenvolvidos no sentido de quantificação e verificação da toxicidade dos D.E presentes no ambiente, praticamente não há na literatura registros de estudos associados ao comportamento e disponibilidade destas substâncias em águas superficiais. Este trabalho buscou determinar a presença dos herbicidas 2,4-D(ácido 2,4-diclorofenoxiacético), Atrazina e Linuron e do inseticida Paration Metil, considerados D.E pela literatura internacional, nas águas do Rio Aporé e propor perspectivas de tratamento de águas de sistemas hídricos por meio de adsorventes sólidos de baixo custo. Este rio está localizado no cerrado brasileiro, o qual é marco divisor do Estado de Mato Grosso do Sul com o Estado de Goiás e recebe grande carga de resíduos de produção agrícola. Após a coleta de amostras de água em pontos estratégicos, foi feita extração pela técnica de Extração em Fase Sólida, em cartuchos de sílica C-18 e a detecção em Cromatografia Gasosa acoplada com detector de Espectrometria de Massas. Os materiais testados para a remoção dos pesticidas alvo deste trabalho foram obtidos a partir de: i) argila organicamente modificada com o surfactante N-dodecil-2-pirrolidona (Mo-DDP); ii) garrafas de PET pós uso (PET); III) biomassa de pinhão manso - J. curcas L. (TPMAN); iv) cinzas de casca de arroz (CCA); v) sílica gel organicamente modificada com 2-Amino-1,3,4- thiadiazol (SGT) e vi) carvão ativado a partir de casca de coco (CA). Os estudos de detecção e quantificação dos pesticidas nas águas do Rio Aporé demonstraram a presença dos pesticidas Malation e Dibutilftalato, os quais são considerados D.E por órgãos governamentais brasileiro, ... / Endocrine disrupters chemical (EDC), such as pesticides, represent an emerging class of contaminants in aquatic systems that can compromise the life of aquatic biota and human. Although some studies are being developed to quantify and verify the toxicity of EDC in the environment, there is almost no literature records related to the conduct studies and availability of these substances in surface waters. The aim of this study was to verity the presence of herbicide 2,4-D (diclorfenoxacetic acid), Atrazine and Linuron and insecticide Methyl Paration in Aporé River to propose perspectives of treatment in these waters by using low cost adsorbents. This river is located at the Brazilian savanna region, river that is located between Mato Grosso do Sul state and Goias state and receives a great amount of agricultural production waste. After collecting an amount of water at strategic points, has been done an extraction by the technical of Solid Phase Extraction, in cartridges of silica C-18, the detection in Gas Chromatography, attached with a detector Mass Spectrometry. The materials tested for the removal of pesticides, targeted in this study, were obtained from the: i) organically modified clays with surfactant N-dodecyl-2-pyrrolidone (Mo-DDP); ii) PET- Polyethylene terephthalate bottle after use (PET); III) biomass of J. curcas L. (TPMAN); iv) rice husk ash (RHA); v) silica gel organically modified with 2-Amino-1,3,4-thiadiazole (SGT) and vi) activated carbon from coconut shell (AC). Studies of detection and quantification of pesticides on the Aporé River‘s water demonstrate the presence of pesticides Malathion and Dibutyl phthalate(DBP), which are considered EDC by Brazilian, American and European government agencies. The adsorbents used had positive parameters to use for removal of these molecules, both in batch studies when fixed bed. The adsorption parameters tested showed that 60 to 120 min. ...

>Magister Scientiae - MSc / The degradation of endocrine disrupting chemicals (EDCs) is a topic of high importance and one that research efforts are continually being focused on. These harmful chemicals are known to cause adverse health effects in humans and animals. In particular, bisphenol-A (BPA), a high volume chemical which is mainly used in the manufacturing of polycarbonate plastics and epoxy resins have been shown to be implicated in the development of a variety of health problems. In this study, the ability of two fungal laccases [Trametes versicolor (TvL) and Trametes pubescens (TpL)], and two bacterial laccases [Streptomyces coelicolor (SLAC), and a mutant of SLAC (SLAC- VN)] to degrade or remove BPA from solution was investigated. The commercial preparation of TvL was used for the purposes of this study, while TpL was produced from the native strain. T. pubescens was cultured in shake-flasks, the supernatant harvested and subjected to ammonium sulphate precipitation. SLAC and SLAC-VN were produced from recombinant strains using a standard protocol and the enzymes purified by size-exclusion chromatography. The presence of the laccases were confirmed by the 2,6-dimethoxyphenol assay and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE).The removal or degradation of BPA from solution was determined for the free enzymes, as well as the enzymes in immobilised form. For immobilisation, the enzymes were encapsulated in sodium alginate beads and cross-linked to form cross- linked enzyme aggregates (CLEAs).High levels of BPA removal was exhibited by the fungal laccase, TpL (100% removal)and the bacterial mutant laccase, SLAC-VN (96%) in their free form. When all four laccases were encapsulated in sodium alginate beads, a number of changes to the characteristics of the enzymes were observed. Overall, the level of BPA removal was reduced for all enzymes as when compared to the free laccases, while SLAC-VN removed more BPA than either of the fungal laccases (59% for SLAC-VN versus 57% TvL and 54% for TpL). The encapsulation of the laccases in alginate beads also led to changes in the optimal temperature for BPA removal, with all encapsulated laccase being able to remove BPA optimally at 40°C. The immobilisation of the laccases in CLEA form had the most significant effect on the BPA removal ability of the laccases. The pH range for both fungal laccases was extended beyond the acidic range [for TpL, optimal removal occurred at pH 8.5 compared to pH 4.5 (free) and pH 6.0 (encapsulated)]. Most remarkable, however, was that the formation of CLEAs greatly enhanced the BPA removal ability of SLAC (60% removal compared to 25% when encapsulated).

Vinclozolin (VCZ), an antiandrogenic fungicide, is an endocrine disrupting chemical that is known to possess high affinity for the androgen receptor (AR) and modulate expression of critical androgen-dependant genes in the prostate. In this study, viability and expression of AR, NKX3.1 and CYP3A4 genes were measured in androgen-sensitive prostate cells LNCaP after exposure to VCZ and VCZ treated with S9 microsomes in a time and dose dependent manner. NKX3.1 is an androgen regulated gene that plays a vital role in prostate development. CYP3A4 is involved in xenobiotic metabolism. VCZ decreased the viability at high doses after 48 hours which was slightly mitigated by treatment with S9 metabolites. Expression of NKX3.1 and CYP3A4 was upregulated while an initial downregulation of AR was observed. NKX3.1 upregulation corroborates with possibility of antiandrogens to act as androgens in LNCaP. The results illustrate that VCZ can interfere with the expression of critical prostate genes.

Magister Scientiae (Medical Bioscience) - MSc(MBS) / Modulation of the male reproductive system occurs as a result of exposure to endocrine disrupting compounds (EDCs) in different life stages. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behavior, as well as decreased libido. Phytochemicals are naturally occurring, biologically active chemical compounds in plants. They are divided into different groups. Isoflavonoids and lignans, are the two major groups of phytoestrogens. Phytoestrogens of teas, coffee and buchu have many beneficial effects on body systems such as antimutagenic, antidiabetic, anti-inflammatory, antibacterial and antiviral properties. They also elicit many adverse events, for example, heavy consumption of green and black tea may cause liver damage and added unwanted effects when combined with other herbal beverages. Chronic heavy consumption of coffee is positively correlated to acute myocardial infarction and can elevate serum cholesterol levels. Rooibos tea decreases steroidogenesis by steroid secreting cell lines.This study investigated the effects of these beverages on the male reproductive system, using a minced testes method for determination of cell viability and hormone (testosterone) production. The first objective of this study was to optimize protein supplement for in vitro testosterone production using human serum albumin (HSA) and foetal bovine serum (FBS). Testicular cultures were prepared and exposed overnight to different concentrations of both sera and then incubated for 4 hours with or without luteinizing hormone (LH). The results showed that addition of protein supplements (HSA or FBS) did not have a significant effect on testosterone production. The second objective of this study was to investigate the effects of green tea, black tea, rooibos tea, coffee and buchu on cell viability of testicular cultures. Cells were treated overnight with varying concentrations of the plant extracts followed by incubation with/without LH for 4 hours. The effects of the plant beverages on cellular protein production were determined by the Bradford assay. The results showed that treatment of cells with varying concentrations of the plant extracts (with/without LH-treatment) had no significant effect on total cellular protein. The third objective of this study was to investigate the effects of black, green and rooibos teas, coffee and buchu on testosterone production by testicular cultures. The results obtained from these experiments showed that rooibos tea and buchu did not affect testosterone production in the presence or absence of LH. The results also indicated that green tea, black tea and coffee inhibited testosterone production by mouse testis cultures in the presence of LH, but not in the absence of LH. Black tea was the most potent inhibitor of testosterone synthesis by mouse testis cultures (IC50= 48 μg/ml), followed by coffee (IC50= 64 μg/ml) and green tea (IC50= 173 μg/ml). Green tea, black tea and coffee inhibited LH-stimulated testosterone synthesis, suggesting that these beverages may impair testicular steroidogenesis in mice. Thus, in spite of their acclaimed beneficial effects, consumption of these beverages in high doses raises concerns for their inhibitory effects on male reproductive function. Further in vitro and in vivo studies are warranted to determine their exact mechanisms of action on the male reproductive system in general and testicular function in particular.

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