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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Impact of Soil Properties on Removal of Emerging Contaminants from Wastewater Effluent During Soil Aquifer Treatment

Riley, Lauren N 01 December 2020 (has links) (PDF)
This study evaluates soil properties that impact the effectiveness of soil aquifer treatment (SAT) as a polishing step to the remove two classes of ECs from wastewater effluent: pharmaceuticals and personal care products (PPCPs), and engineering nanomaterials (ENMs). In recent years, it has been determined that elevated levels of emerging contaminants (ECs) are being released into the environment with wastewater effluent. ECs are proven to cause adverse environmental and health effects as a result of long-term exposure. It is important to evaluate sustainable solutions to improve the current methods of wastewater treatment to address these ECs. Soil aquifer treatment (SAT) is a sustainable, cost effect treatment alternative to advanced treatment at a wastewater treatment plant. SAT replenishes local groundwater supplies while allowing for indirect potable reuse, if contaminants of concern such as ECs can be effectively removed from the water. Since wastewater effluent can contain a variety of contaminants with myriad physical and chemical properties, understanding the potential of the aquifer itself to provide EC removal is a key step in establishing SAT as a viable treatment alternative. Peer-reviewed research studies were analyzed to determine the soil properties that affect the fate and transport of ECs in the aquifer environment. The data was complied to produce recommendations for an effective SAT site. Physical and chemical properties of the soil facilitate contaminant removal as the groundwater flows through the aquifer. This study determined that removal of ECs from effluent had a correlation with (1) high clay content, (2) small Darcy Velocity, (3) high soil organic matter content, and (4) low sand content. Based on the 6 peer-reviewed research studies reviewed, the removal of nanomaterials is affected by clay content and sand content, but not soil organic matter content. Conversely, the removal of PPCPs is affected by clay content and soil organic mater content, but not sand content. It can be concluded that two different removal mechanisms facilitate the removal of nanomaterials versus PPCPs; physical removal for nanomaterials and chemical removal (sorption) for PPCPs. Clay facilitates the removal of both contaminants. The small soil diameter of clay forms smaller pores in the soil media. This causes increased pore straining, while also restricting the flow through the soil, which increases the contact time between the soil particle and the ECs. Additionally, clay has a large surface area, which increases surface interactions, such as sorption, of the EC to the surface of the clay particle.
52

Optimization and Longevity of Functionalized Multi-Walled Carbon Nanotube-Enabled Membranes for Water Treatment

White, Madeleine Michael Isabella 01 June 2020 (has links) (PDF)
Water scarcity is a growing concern at the global scale. Large scale water reuse is growing both in necessity and popularity. Before water reuse can be performed efficiently on a large scale or be used for potable supply, even indirectly, contaminants of emerging concern (CECs) will need to be treated at the full scale. Advanced oxidation processes (AOPs) are a form of advanced water treatment capable of treating a wide range of CECs. This study contributes to the growing field of AOPs and more specifically AOPs using ozone combined with functionalized multi-walled carbon nanotubes (MWCNTs). Ozonation of MWCNTs has been found to increase hydroxyl radical production and improve AOP treatment. Novel MWCNT-enabled membranes were used as catalysts for ozonation to degrade the CEC Atrazine. Atrazine is an ozone recalcitrant CEC that is commonly found in herbicides. Atrazine removal results, found using a high-performance liquid chromatograph (HPLC), were inconsistent between membranes constructed using identical procedures. Further analysis using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopes (SEM), and UV-Vis spectrophotometry was conducted to explore inconsistencies in construction of the membranes which might explain removal inconsistencies and predict membrane longevity. Removal was found to be influenced by filtration time and ozone exposure. Ozone exposure and filtration time influence percent removal because they both affect hydroxyl formation. The membrane test filtration duration, for equal filtered volumes, ranged from under 5 minutes to nearly an hour. It is believed that filtration time inconsistency was due to inconsistent MWCNT loading on the surface of the membranes. Extended exposure to ozone might change the surface chemistry of the MWCNTs on the membrane surface, affecting hydroxyl radical production. Additionally, repeated use of the membrane created surface defects that might reduce the membrane strength. This study found that the lifetime of the membrane is far past what was simulated in lab and further testing must be performed.
53

Removal of Emerging Contaminants from Aqueous Solutions by Using Polymeric Resins

Liu, Dan January 2011 (has links)
The emerging contaminants (ECs) such as estrogen hormones, perfluorinated compounds (PFCs), bisphenol A (BPA) and 1, 4-dioxane have been detected in natural water bodies at a noticeable level worldwide. The presence of ECs in the aquatic environment can pose potential threats to aquatic organisms as well as human world. Ion-exchange is a highly efficient technology for the removal of heavy metal ions and natural organic materials (NOMs) due to the nature of exchanging similar charged ions. However, this technology has not been explored for removing ECs. In this study, four categories of ECs: estrogen hormones (12), perfluorinated compounds (10), bisphenol A and 1, 4-dioxane were used as model contaminants. The adsorption of each category of ECs onto various types of polymeric resins (MN100, MN200, A530E, A532E and C115) was investigated. The removal of ECs was tested under batch and column mode. The effects of pH, resin dosage, and contact time on the removal of ECs were studied in batch mode; isotherm and kinetics models were applied to fit the experimental data. Column experiments were conducted to verify the practicability of the polymeric resins. Adsorption results have shown that both MN100 and MN200 resins could efficiently remove estrogen hormones mixture (more than 95%), and bisphenol A (more than 80%) with the initial concentration of 100 ìg/L; A532E and A530E could remove perfuorinated compounds mixture (more than 99%) with the initial concentration of 100 ìg/L. As pH increased from 9 to 11, the adsorption capacity onto polymeric resins decreased dramatically for estrogen hormones such as 17á-ethinylestradiol, estriol, 17â-estradiol, 17á-estradiol, estrone, 17á-dihydroequilin and equilin as well as bisphenol A. The adsorption of estrogen hormones and bisphenol A onto MN100 and MN200 resins reached the equilibrium within 24 hours, whereas the adsorption of perfluorinated compounds onto A532E and A530E reached the equilibrium within 8 hours. It was also observed that the adsorption of PFCs largely depends on the C-C chain length. PFCs with longer chain yielded lower adsorption efficiency onto the ion-exchange resins A532E and A530E. Adding salinity decreased the first-order rate constants for the adsorption of bisphenol A onto MN100 and MN200 resins. Fixed-bed column experiment results with estrogen hormones mixtures confirmed that the polymeric resins were good candidates in the removal of estrogen hormones. Trimegestone was the first compound detected in the effluent in the column test while 17â-estradiol, 17á-estradiol were the last. 80% of the exhausted resins (MN100 and MN200) by bisphenol A were regenerated by using pure methanol as regeneration solution. Polymeric resins were not effectively removing 1, 4-dioxane from the aqueous solution. / Civil Engineering
54

REMOVAL OF EMERGING CONTAMINANTS FROM AQUEOUS SOLUTION BY OZONE -BASED PROCESSES

Rani, Rupam January 2013 (has links)
The presence of emerging contaminants (ECs) in water and wastewater systems has become a subject of significant concern worldwide. These emerging contaminants are complex organic molecules which potentially affect human health and environment. Conventional wastewater treatment plants are unable to completely remove these contaminants from water and therefore can discharge them into environment. The need to develop effective methods for ECs removal is essential. This study assess the potential of ozone based advanced oxidation processes (AOP) to oxidize number of emerging contaminants. Different combinations of ozone with hydrogen peroxide and sodium persulfate were tested. For this study 1-4, dioxane, perfluorinated compounds (PFCs), N,N-Diethyl-metatoluamide, and three pharmaceuticals sulfamethoxazole, trimethoprim and carbamazepine have been selected. The effect of different process parameters such as chemical dosages, ozone weight percent, ozone flow rates, etc. on destruction of ECs were examined. It was observed that 1, 4-dioxane were persistent to direct ozone reaction, however were easily oxidized by hydroxyl radical. However, ozonation was solely very effective (> 99 %) in removing pharmaceuticals such as sulfamethoxaole, trimethoprim and carbamazepine. It was not very efficient for the removal of perfluorinated compound and N,N-Diethylmeta-toluamide. The operational conditions were optimized for maximum removal of every compound and their influence on the degradation process is discussed. / Civil Engineering
55

Impact of Manure Management Practices on the Environmental Fate of Antibiotics in Manure-Applied Fields

Le, Hanh Thi Van 10 September 2019 (has links)
Antibiotics and antibiotic resistance genes from animal manure applied to soil as fertilizer are now among the most concerned contaminants in soil. The widespread use of antibiotics in livestock might amplify the risk of developing antibiotic resistance, causing once treatable diseases to turn deadly. The World Health Organization declared antibiotic resistance as "one of the biggest threats to global health, food security, and development". The goal of this dissertation was to develop best manure management practices by understanding the behavior of manure-associated antibiotics in manure, water, and soil. In particular, my research focused on the effects of manure application methods, on-site manure treatment methods, manure application seasons, and manure-rainfall time gaps on antibiotic surface runoff losses, antibiotic distribution and movement in soil, antibiotic dissipation in soil, and development of antibiotic resistance. Rainfall simulation field-scale and soil incubation lab studies were combined to find the best manure management practices. My research has shown for the first time that using the manure soil subsurface injection method, especially during spring application season due to moist soil, applying manure at least 3 days before a subsequent rainfall, and using composted manure, can significantly reduce the quantity of antibiotic loss with runoff from manure-applied fields to the surrounding environment. The majority of applied antibiotics remained in soil. All antibiotics showed a similar dissipation pattern with fastest kinetics during the first 14 d before slowing down. The effect of two manure application methods on antibiotic dissipation kinetics varied with different antibiotics. Although the half-life of tested antibiotics in soil was short (<21 days), some remained detectable even at 6 months after a single manure application. Results also showed that compared to the surface application, the subsurface injection slits acted as a "hot zone" with a higher amount of antibiotics, manure microbes, and antibiotic resistance. The results provide information for policy makers, manure managers, and farmers to develop better manure management practices that can use manure as fertilizer while minimizing the spread of antibiotics to surrounding water, soil, and plants. / Doctor of Philosophy / There is growing concern about antibiotic resistance as a serious human health threat because a resistant infection may kill, can spread, and increases health costs. Every year in the United States, there are 2 million people infected with antibiotic resistant bacteria, 23,000 people die as a direct result of these infections, and $55 billion is lost due to increased hospital stay and lost work days. Although bacteria naturally develop the ability to resist antibiotics, the problem is the length between antibiotic introduction and resistance development is shortening because of the widespread and overuse of antibiotics, especially in the livestock industry. The goal of this study was to develop the best manure management practices balancing the benefits of antibiotics in livestock and animal manure and their impact on the environment. In particular, we monitored, using field-scale and laboratory studies, the effects of manure application methods, on-site manure treatment methods, manure application seasons, and manure-rainfall time gaps on antibiotic loss through surface runoff, antibiotic distribution and movement in soil, antibiotic dissipation in soil, and development of antibiotic resistance. In order to reduce the amount of antibiotic loss with surface runoff from manure-applied fields to the surrounding environment, farmers are recommended to 1) compost manure before application, 2) watch the forecast to apply manure at least 3 days before a subsequent rainfall, and 3) use the subsurface injection method, especially when the soil is wet (spring season). The majority of applied antibiotics remained in soil. All tested antibiotics showed a similar dissipation pattern with the fastest rate during the first two weeks after manure application, then slowing down. Although the half-life of tested antibiotics in soil was short (<21 days), some remained detectable even at 6 months after a single manure application. Besides, the subsurface injection slits acted as a hot zone with a concentrated amount of antibiotics, manure microbes, and antibiotic resistance. The results provide recommendations for policy makers, manure managers, and farmers to maximize benefits of manure as fertilizer while minimizing the spread of manure-associated antibiotics to surrounding water, soil, and plants.
56

The Occurrence and Fate of Steroid Hormones from Manure Amended Agriculture Fields

Sosienski, Theresa Ann 14 July 2017 (has links)
Hormones are endocrine disrupting compounds, which have been shown to alter the sexual development of aquatic organisms. Animal manure applications to agricultural fields for nutrient management can be a source of environmental hormones. This dissertation investigates the occurrence of hormones in fields applied with various manures and their adjacent streams, as well as the effect of manure application technologies on the fate of hormones in soils, sediments, and runoff. A total of 11 hormone compounds were studied. All studied analytes were quantified using liquid chromatography and triple-quadrupole mass spectrometry following various sample extraction and clean-up strategies. The spatial and temporal distribution of manure-associated hormones in a manure surface applied agricultural field and adjacent stream was studied at time points up to 7.5 months after a routine manure application. Hormones were detected mainly in the top 0-5cm soils. Significantly higher levels of hormones were found in the drystack applied area of the field when compared to dairy manure slurry applied portion. New technologies for the subsurface application of poultry litter show promise as a tool to reduce the transportation of environmental hormones in surface runoff. Once adequate sampling protocols were established; it was determined that subsurface injection of both dairy manure and poultry litter reduced the impact of manure surface runoff. Hormones also showed little vertical and lateral movement in the soil. The transformation rates of 1,4-androstadiene-3,17-dione, 4-androstene-3,17-dione and estrone were studied comparing the effects of temperature, soil type, and application type. The calculated half-life of 1,4-androstadiene-3,17-dione in poultry litter surface-applied soils was 1.9 times higher than that in the poultry litter subsurface-injected soils, indicating a faster dissipation rate in the injection slits. Estrone persisted at detectable levels for the duration of the study in all treatments. The continued use of best management practices and innovative manure management techniques for the reduction of nutrients, sediment and other contaminants has the potential to also reduce hormone transport to the natural environment. Monitoring many different types of hormones in all areas of an environmental system will continue to provide better information on the occurrence and fate of hormones sourced from manure amended soils. / Ph. D.
57

Emerging Contaminants: Occurrence of ECs in Two Virginia Counties Private Well Water Supplies and Their Removal from Secondary Wastewater Effluent

Vesely, William C. 29 June 2018 (has links)
Emerging contaminants (ECs) are chemicals such as pharmaceuticals and personal care products that have been detected in various environmental matrices, including drinking water supplies at trace concentrations (ng/L-ug/L or ng/kg-ug/kg). Current wastewater treatment plant technology is largely ineffective at removing ECs. The objectives of this investigation were to: 1) determine the occurrence of ECs in private well water supplies in Montgomery and Roanoke County, VA 2) quantify the concentrations of three ECs in selected private water supplies; 3) examine the relationship between water quality constituents (nitrate, bacteria, pH and total dissolved solids) to EC occurrence in private water supplies; and 4) determine the ability of the MicroEvapTM, a novel wastewater treatment technology, to remove ECs from secondary wastewater effluent. In partnership with the Virginia Household Water Quality Program, 57 private water supplies were sampled and tested for the occurrence of 142 ECs and 43 other water quality constituents. Up to 73 ECs were detected in the sampled private water supplies. Higher numbers of ECs detected in the tested private water supplies were related with nitrate >1 mg/L, total dissolved solids >250 mg/L, and the presence of total coliform bacteria. Results indicate the MicroEvapTM technology had >99% removal effectiveness for all 26 tested ECs from three secondary wastewater effluent. With the increasing detection of ECs in water bodies, it is essential to understand the occurrence of ECs and environmental predictors of EC presence in different water matrices and continue to develop water treatment technology capable of treating wastewater for EC removal. / Master of Science
58

Desenvolvimento de um método para determinação de disruptores endócrinos em saliva por microextração líquido-líquido dispersiva e cromatografia líquida de alta eficiência acoplada à espectrometria de massas / Method development for determination of endocrine disrupting in saliva by dispersive liquid-liquid microextraction and high performance liquid chromatography-tandem mass spectrometry

Oliveira, Mariana Lepri de 11 May 2018 (has links)
A crescente demanda por novos compostos químicos sintéticos para atender as necessidades médicas, agrícolas e industriais da população resultou no surgimento de novos contaminantes, denominados emergentes. Com a intensa utilização destes compostos em diversos produtos e o consequente aumento da concentração destes no meio ambiente, a população passou a estar exposta e sujeita aos seus possíveis efeitos deletérios. Os disruptores endócrinos fazem parte do grupo de contaminantes emergentes que tem a capacidade de interferir na ação natural dos hormônios por diferentes mecanismos, podendo agravar o quadro de doenças pré-existentes e causar diversos outros danos à saúde humana. Apesar de serem largamente utilizados na vida cotidiana, a regulamentação do uso desses compostos ainda é quase inexistente, aumentando a preocupação quanto à sua segurança. Comumente, os estudos de biomonitoramento humano para avaliar a exposição da população em geral são realizados utilizando amostras de sangue e urina. Neste sentido, o presente estudo teve como objetivo desenvolver um método alternativo para determinação simultânea de 17 compostos classificados como disruptores endócrinos: bisfenóis, parabenos, benzofenonas e triclocarban em saliva, empregando a microextração líquido-liquido dispersiva (DLLME) no preparo da amostra e cromatografia líquida de alta eficiência acoplada à espectrometria de massas (LC-MS/MS) para a determinação. Os seguintes parâmetros foram avaliados na otimização da DLLME: volume e tipo de solvente extrator e dispersor, força iônica, pH e agitação. Após a otimização, o processo de extração foi realizado adicionando-se 500 ?L de água deionizada à 500 ?L da amostra de saliva. Os solventes extrator e dispersor selecionados foram triclorometano e acetona, respectivamente (volume de 2 mL da mistura na proporção 1:3). Foi adicionada a etapa de agitação manual por dez segundos. As curvas de calibração de todos os analitos apresentaram linearidade, com coeficiente de correlação superiores a 0,99 no intervalo de concentração de 1-20 ng mL-1. O coeficiente de variação (CV) intra e interdias foram inferiores a 20% para o primeiro ponto da faixa linear e inferiores a 15% para as demais concentrações. O erro padrão relativo intra e interdias foram inferiores a 20% para o primeiro ponto da faixa linear e inferiores a 15% nas demais concentrações. Os limites de detecção (LOD) e de quantificação (LOQ) encontrados variaram de 0,01 - 0,15 ng mL-1 e 0,05 - 0,40 ng mL-1, respectivamente. Para avaliar a aplicabilidade do método, dez amostras de saliva foram analisadas e apresentaram concentrações detectáveis de bisfenol S (BPS), bisfenol AF (BPAF) e propilparabeno (PrP) ( <LOQ). O bisfenol A (BPA) e a benzofenona-3 (BP3) foram encontrados em concentrações que variaram entre 1,01-3,14 e 1,00-2,50 ng mL-1, respectivamente. O metilparabeno (MeP) foi detectado em todas as amostras, atingindo, nos níveis quantificáveis, a concentração de 17,8 ng mL-1. Portanto, o método aqui proposto é uma alternativa simples e rápida para estudos de biomonitoramento humano, capaz de determinar 17 analitos multi-classes simultaneamente com uso de baixo volume de solventes. / The growing demand of new synthetic chemical compounds to attend the medical, agricultural and industrial needs of the population has resulted in the emergence of new contaminants, known as emerging contaminants. The presence of these contaminants in several products, and its consequent concentration increase in the environment, exposed the population and subject them to possible deleterious effects. Endocrine disruptors are a group of these contaminants that have the ability to interfere at the natural action of hormones by different mechanisms, wich can worsen preexistent diseases and cause other damages to humam health. Despite the widely utilization of these compounds in everyday life, regulation of its use is almost non-existent, raising concerns about their safety. Mostly human biomonitoring studies to assess the exposure of the population are performed in urine and blood samples. In these sense, the present study aimed to develop an alternative method for simultaneous determination of 17 endocrine disrupting compounds: bisphenols, parabens, benzophenones and triclocarban in saliva, using dispersive liquid-liquid microextraction (DLLME) at sample preparation and high performance liquid chromatography coupled to mass spectrometry (LC-MS/MS) for determination. The evaluated parameters in the optimization of DLLME were: volume and type of extraction and disperser solvents, ionic strength, pH and agitation. After the optimization, the extraction procedure was performed by adding 500 ?L of deionized water to 500 ?L of saliva sample. The extraction and disperser solvents selected were trichloromethane and acetone, respectively (2 mL of the mixture in 1:3 ratio). The manual agitation for ten seconds. The matrix-matched calibration curves of all analytes were linear, with correlation coefficients higher than 0.99 in the range level of 1 - 20 ng mL-1. The intra and interday coefficient of variation (CV) was less than 20% for the first point of the linear range and less than 15% for the other concentrations. The intra and interday relative standard deviation (RSD) was less than 20% for the first point of the linear range and less than 15% for the other concentrations. The limits of detection (LOD) and quantification (LOQ) ranged from 0,01 - 0,15 ng mL-1 and 0,05 - 0,4 ng mL-1, respectively. To evaluate the applicability of the method, ten saliva samples were analyzed, showing detectable concentrations (<LOQ) of bisphenol S (BPS), bisphenol AF (BPAF) and propylparaben (PrP). Bisphenol A (BPA) and benzophenone-3 (BP3) were found in ranging concentrations from 1,01 - 3,14 and 1,00 - 2,50 ng mL-1, respectively. Methylparaben (MeP) was detected in all samples, reaching, at the quantifiable levels, the concentration of 17,8 ng mL-1. Thus, the proposed method is a simple and fast alternative for human biomonitoring studies, capable of determining 17 multi-class analytes simultaneously using low volume of solvent.
59

Abordagem metodológica para a valuação do petencial desregulador endócrino de água de beber: estudo com amostras reais / A methodological aprroch to evaluate endocrine disrupting activity of drinking water: real samples study in rats

Solano, Marize de Lourdes Marzo [UNESP] 10 February 2014 (has links) (PDF)
Made available in DSpace on 2015-05-14T16:53:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-10Bitstream added on 2015-05-14T16:58:55Z : No. of bitstreams: 1 000829087.pdf: 399761 bytes, checksum: 6162c9ec05a5f035f48858f6dc7daf87 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / If contaminated waters are treated by conventional processes (WTP) emerging contaminants are not fully removed and will remain in the drinking water (DW). We investigated the potential for endocrine disruption of two DW samples collected in 2010 and 2012 from a WTP located in São Paulo, Brazil. Water samples were extracted and chemically analyzed for emerging substances and evaluated with an in vitro bioluminescent yeast assay containing estrogen/androgen human receptors (BLYES/BLYAS). In vivo assays were conducted with 21-day old female rats exposed to DW extracts for 03 (uterotrophic assay; OECD) or 20-days (pubertal assay, EPA). The exposure represented a daily ingestion of 2 L, 5 L and 10 L of DW by a 60 kg human being. Caffeine (5.8 - 21 ug/L), estrone (1 ng/L), atrazine (2.2 -11.2 ng/L), carbendazim (0.22 ng/L), azoxistrobina (0.23 ng/L) and tebuconazole (0.19 ng/L) were detected in DW by LC-MS/MS-ESI. There were no increase of the uterus wet weight in the uterotrophic assay, and no alteration of the vaginal opening moment in the pubertal assay. However, there was increased relative blotted uterus weight in animals treated for 3-days with both DW. Levels of LH and FSH presented a significant dose-response increase in the uterotrophic assay developed with the 2010 sample. This happened in association with a significantly increased incidence of vaginal keratinization after the 3-day exposure. Results suggest the DW tested exerted hypothalamic-hypofisis activity alteration in vivo. Additional end-points in standard protocols could be useful to evaluate the presence of endocrine disruptor activity in DW
60

Abordagem metodológica para avaliação do potencial desregulador endócrino de água de beber : estudo com amostras reais /

Solano, Marize de Lourdes Marzo. January 2014 (has links)
Orientador: João Lauro Viana de Camargo / Coorientador: Gisela de Aragão Umbuzeiro / Banca: Ione Pellegatti Lemonica / Banca: Patrícia Carvalho Garcia / Banca: Anderson Joel Martino Andrade / Banca: Daniela Cristina Ceccatto Gerardin / Resumo: Não disponível / Abstract: If contaminated waters are treated by conventional processes (WTP) emerging contaminants are not fully removed and will remain in the drinking water (DW). We investigated the potential for endocrine disruption of two DW samples collected in 2010 and 2012 from a WTP located in São Paulo, Brazil. Water samples were extracted and chemically analyzed for emerging substances and evaluated with an in vitro bioluminescent yeast assay containing estrogen/androgen human receptors (BLYES/BLYAS). In vivo assays were conducted with 21-day old female rats exposed to DW extracts for 03 (uterotrophic assay; OECD) or 20-days (pubertal assay, EPA). The exposure represented a daily ingestion of 2 L, 5 L and 10 L of DW by a 60 kg human being. Caffeine (5.8 - 21 ug/L), estrone (1 ng/L), atrazine (2.2 -11.2 ng/L), carbendazim (0.22 ng/L), azoxistrobina (0.23 ng/L) and tebuconazole (0.19 ng/L) were detected in DW by LC-MS/MS-ESI. There were no increase of the uterus wet weight in the uterotrophic assay, and no alteration of the vaginal opening moment in the pubertal assay. However, there was increased relative blotted uterus weight in animals treated for 3-days with both DW. Levels of LH and FSH presented a significant dose-response increase in the uterotrophic assay developed with the 2010 sample. This happened in association with a significantly increased incidence of vaginal keratinization after the 3-day exposure. Results suggest the DW tested exerted hypothalamic-hypofisis activity alteration in vivo. Additional end-points in standard protocols could be useful to evaluate the presence of endocrine disruptor activity in DW / Doutor

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