Browsing by Author "Foureaux, Nathalia S."
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- Monitoring of 17 β-estradiol in raw and treated samples of wastewater treatment plantsPublication . Foureaux, Nathalia S.; Carneiro, Eduardo V.; Ribeiro, António E.; Brito, Paulo; Queiroz, AnaNowadays, monitoring the concentration levels of estrogens in treated wastewaters of wastewater treatment plants (WWTP) is an environmental mandatory task to minimize or eliminate water pollution. The present work is divided in two main experimental stages. First, an SPE/HPLC-UV experimental methodology is optimized to detect and quantify 17β-Estradiol (E2) present in aqueous samples. The HPLC-UV operating conditions were selected by performing a screening between 10 different mobile phase compositions. A pure methanol composition was selected based in the lower retention time and the highest UV detector signal. The solid phase extraction optimization involves a three-level Box-Behnken experimental design with four factors (sample volume, sample pH, adsorbent drying time and solvent composition used for the washing step), combined with a response surface methodology. The validation of the optimized experimental methodology is done by the monitoring of estradiol in wastewater influent and effluent samples from Bragança Wastewater Treatment Plant in Portugal.
- Monitoring of 17 β-estradiol in raw and treated waters of wastewater treatment plantsPublication . Foureaux, Nathalia S.; Carneiro, Eduardo V.; Ribeiro, António E.; Brito, Paulo; Queiroz, AnaNowadays, there has been a growing concern regarding the possible consequences of exposure to estrogens through its direct or indirect consumption
- Monitoring of 17 β-Estradiol in raw and treated waters of wastewater treatment plantsPublication . Foureaux, Nathalia S.; Carneiro, Eduardo V.; Ribeiro, António E.; Brito, Paulo; Queiroz, AnaNowadays, there has been a growing concern regarding the possible consequences of exposure to estrogens through its direct or indirect consumption
- Monitoring of 17B-estradiol in raw and treated samples of wastewater treatment plantsPublication . Foureaux, Nathalia S.; Queiroz, Ana; Ribeiro, António E.; Carneiro, Eduardo V.Aquatic environment pollution is a keen subject in the most important discussions surrounding global issues. With the increase of industrialization, globalization and urbanization, as consequence, there is an increase in production of high-level pollutants. Emerging pollutants (EP’s) are compounds which are, usually, not found in natural water sources. Data concerning the occurrence and concentrations of some pharmaceuticals in effluents from WWTPs and surface waters, shows that EP concentrations in effluents fluctuate widely, most probably due to inconsistent efficiency of wastewater treatment. Endocrine disrupting compounds (EDCs), are an important group of EP’s, considering they are often found in different aquatic matrices. Nowadays, monitoring the concentration levels of estrogens in treated wastewaters of wastewater treatment plants (WWTP) is an environmental mandatory task to minimize or eliminate water pollution. The present work is divided in two main experimental stages. First, an SPE/HPLC-UV experimental methodology is optimized to detect and quantify 17β-Estradiol (E2) present in aqueous samples. The HPLC-UV operating conditions were selected by performing a screening between 10 different mobile phase compositions. A pure methanol composition was selected based in the lower retention time and the highest UV detector signal. The solid phase extraction optimization involves a three-level Box-Behnken experimental design with four factors (sample volume, sample pH, adsorbent drying time and solvent composition used for the washing step), combined with a response surface methodology. The implementation of the optimized experimental methodology occurred by the monitoring of estradiol in a wastewater influent and effluent samples. E2 was detected and quantified in three different samples collected from three distinct point of a WWTP. Sample 1 was collected from the entrance point, sample 2 was collected from the activated sludge aeration tank and sample 3 was the completely treated effluent. The concentration of E2 found in three points was higher than what was anticipated, but coherent with other works.
- Optimization of estradiol monitoring in raw and treated wastewater samples by response surface methodologyPublication . Queiroz, Ana; Foureaux, Nathalia S.; Carneiro, Eduardo V.; Ribeiro, António E.; Brito, PauloThe ever-increasing use of endocrine disruptors compounds (EDCs), through pharmaceuticals such as synthetic estrogens, both in humans as well as in animals, are raising its concentration in the environment. Estradiol, also designed as 17β-Estradiol (see Fig. 1), belongs to the pharmaceutical class of steroid estrogens and was included in the “Watch List” since 2013 the Directive 2013/39/EU due to its potential risk to human health and environment. The low removal efficiency of estrogens by the conventional wastewater treatment plants (WWTPs), becomes a major source of their release into different aquatic matrices. Therefore, the occurrence and, more importantly, the destination of these compounds are matters of utmost importance towards a better public health. The aim of this work is the optimization of solid phase extraction/high performance liquid chromatography (SPE/HPLC) using the response surface methodology (RSM) to detect and quantify 17β-Estradiol in WWTPs effluents.
- Optimization of estradiol monitoring in raw and treated wastewater samples by response surface methodologyPublication . Queiroz, Ana; Brito, Paulo; Ribeiro, António E.; Carneiro, Eduardo V.; Foureaux, Nathalia S.Estradiol, also designed as 17-beta-estradiol, belongs to the pharmaceutical class of steroid estrogens and was included in the "Watch List" since 2013 by the Directive 2013/39/EU due to its potential risk to human health and environment. The low removal efficiency of estrogens by the conventional wastewater treatment plants, becomes a major source of their release into different aquatic matrices. This work presents the optimization of an analytical methodology based on solid phase extraction and high-performance liquid chromatography using the response surface methodology to detect and quantify 17-beta-Estradiol in wastewater treatment plant effluents. From a set of 10 studied solvent/mixture compositions, pure methanol was selected as the better choice to use as mobile phase composition for liquid chromatography. The solid phase extraction step was optimized using a three-level Box-Behnken experimental design with sample volume, sample pH, adsorbent drying time and solvent composition in the washing step, as the four factors to be studied. The sample volume of 500 mL, a sample pH value adjusted to a value of 2, an adsorbent drying time of 60 min and the use of 10% of methanol in the adsorbent washing step were the obtained optimized conditions. The pH value was concluded to be the more significant parameter for average recuperations of estradiol higher than 80%. The method validation was performed by monitoring 17-beta-estradiol in real wastewater treatment plant samples, collected from raw affluent, secondary treatment and treated effluent. The methodology was tested successfully, and estradiol was quantified in all the three studied samples.
- Optimization of SPE/HPLC analytical method for 17β-estradiol quantification in wastewater treatment plant (in)effluents using a surface responsive methodologyPublication . Foureaux, Nathalia S.; Carneiro, Eduardo V.; Ribeiro, António E.; Brito, Paulo; Queiroz, AnaThe ever increasing use of endocrine disruptors compounds (EDCs), through pharmaceuticals such as synthetic estrogens, both in humans as well as in animals are becoming ubiquitous in the environment