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Écotoxicité, cytotoxicité et potentiel androgène des résidus pharmaceutiques sur les deux modèles biologiques : Hydra attenuata et les cellules MDA-Kb2 / Ecotoxicity, cytotoxicity and androgenic potential pharmaceutical residues on two biological models : Hydra attenuata and MDA-KB2 cellsBenchouala, Amira 07 July 2016 (has links)
L’objectif de ce travail a consisté à évaluer différents effets écotoxiques, cytotoxique et le potentiel androgénique de 14 produits pharmaceutiques: la clomipramine, la fluoxétine, la fluvoxamine, la paroxétine, la sertraline et la venlafaxine (antidépresseurs), l’amphotéricine B, l’éconazole, le kétoconazole et le miconazole (antifongiques), la clarithromycine (antibiotique), l’acébutolol (ß-bloquants), le gabapentine (antiépileptiques) et la cétirizine (antihistaminiques), à l’aide d’études in vivo et in vitro. Les tests d’écotoxicité aiguë (96h) sur le cnidaire d’eau douce Hydra attenuata ont montré un effet délétère sur la survie des hydres adultes, la morphologie et le développement des embryons pour l’ensemble d’antidépresseurs et des antifongiques testés. Les valeurs de CE50 calculées ont révélé que l’éconazole, le miconazole et la sertraline sont les molécules les plus toxiques. Les tests d’écotoxicité chronique sur les hydres adultes (10 jours) et les embryons (14 jours) ont mis en évidence que la plus part des molécules d’antidépresseurs testées sont des embryotoxiques et tératogènes puisque ils induisent des malformations chez les embryons contrairement aux antifongiques qui présentent des anomalies seulement chez les adultes. Ces tests ont montré aussi que les molécules d’antidépresseurs testées seules sont moins toxiques que lorsqu’elles sont testées en mélange. En effet, le mélange de molécules antidépresseurs testées présente une toxicité plus élevée sur les adultes que sur les embryons, avec une concentration minimale induisant des effets significatifs de l’ordre de ng L-1, concentrations proches de celles retrouvées dans l’environnement. De plus, les résultats d’écotoxicité chronique sur plusieurs générations d’hydres ont montré que la morphologie des individus de la première génération (F0) ainsi que ceux de la deuxième génération (F1) été affectée de la même manière, démontrant une sensibilité du même ordre vis-à-vis de la sertraline ou du mélange d’antidépresseurs, tandis que les individus issus de la troisième génération (F2) apparaissent moins sensibles lors de l'exposition à la sertraline. Par contre, la reproduction des hydres exposées à la sertraline est diminué de plus en plus dans chaque génération, avec une toxicité plus importante pour les individus de la troisième génération. Le mélange d’antidépresseurs affecte la reproduction des hydres de la deuxième génération F1 à des concentrations environnementales. Les essais in vitro conduits sur les mêmes molécules pharmaceutiques, testées seules et en mélange, sur les cellules MDA-Kb2 n'ont révélé aucun effet androgénique et cytotoxique sur les cellules à des concentrations environnementales / The objective of this work was to evaluate different ecotoxic, cytotoxic and androgenic effects of 14 pharmaceutical compounds: clomipramine, fluoxetine, fluvoxamine, paroxetine, sertraline and venlafaxine, amphotericin B, éconazole, ketoconazole and miconazole, clarithromycin, the acebutolol, gabapentin and cetirizine, using in vivo and in vitro studies. The acute ecotoxicity tests (96h) on the freshwater cnidarian Hydra attenuata showed deleterious effects on adult survival, morphology and embryo development for all tested antidepressants and antifungals drug. The values of EC50 concentrations revealed that econazole, miconazole and sertraline are the most toxic molecules. The chronic ecotoxicity tests on hydras adults (10 days) and embryos (14 days) revealed that most of the molecules tested antidepressants are embryotoxic and teratogenic as they cause malformations in embryos contrary to antifungal which display abnormalities in adults only. These tests also showed that antidepressants tested individually are less toxic than when tested as a mixture. This mixture has a higher toxicity on adults than on embryos, with significant effects concentrations around ng L-1 which are close to measured environmental concentrations. In addition, chronic ecotoxicity results over several generations of hydras have shown identical sensitivity of both first and second generation on morphology of individuals. No more toxicity was observed on the third generation of hydra. Concerning the reproduction of hydras, this parameters was strongly decreased in all generations with an increasing sensitivity of individuals along the generations. Moreover, the mixture of antidepressants affect reproduction of hydras for the second generation at environmental concentrations. In vitro tests conducted on MDA-KB2 cells with the same pharmaceuticals revealed that these compounds tested did not exert any androgenic and cytotoxic effect on cells in culture at environmental concentrations
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The suitability of estrogen and androgen bioassays for the measurement of endocrine activity in different water matricesNgcobo, Silindile January 2017 (has links)
Endocrine disrupting chemicals (EDCs) are ubiquitous in the environment and their
presence in water bodies is documented. They discharge into surface water (SW)
unmonitored, posing a threat to both aquatic and terrestrial lives. This is a challenge
as not all populations have access to treated drinking water (TDW). The EDC
contaminated serves as a route of exposure, together with ineffective treatment
plants. Given the complexity of the endocrine system, EDCs may mimic or
antagonise natural hormones or disrupt their synthesis, metabolism and excretion.
The associated health effects include testicular dysgenesis syndrome, metabolic
disorders and cancers. Policy and internationally standardised test methods are
however sti ll limited. This study therefore aimed to assess the suitability of two
assays used for screening estrogenic activity and one for androgenic activity in
different water sources.
The study consisted of two phases. In phase 1, water sample (tap, surface and
treated wastewater) were collected from a catchment area in Pretoria. The samples
and a spiked MilliQ laboratory water sample were extracted with solid phase
extraction (SPE) and sent to Germany for distribution to participating laboratories.
Samples (n=24) from six different countries were received to test for androgenic
activity in the MDA-kb2 reporter gene assay. In phase 2, SW and TDW samples
were collected from April 2015 until March 2016. The samples were filtered,
extracted using SPE and assayed with the YES assay, T47D-KBluc reporter gene
assay for estrogenic activity and MDA-kb2 reporter gene assay for androgenic
activity. In phase 1, androgenic activity was detected in 4 out of 24 (21%) samples and
ranged from 0.23 ± 0.040 ng/L to 0.008 ± 0.001 ng/L DHTEqs. In phase 2,
estrogenic activity was detected in 16 out of 24 (67%) SW samples in the T47DKBluc
reporter gene assay and ranged from 0.31 ± 0.05 pg/L to 10.51 ± 5.74 pg/L
EEqs. It was below the detection limit (dl) in the YES assay. Androgenic activity was
detected in 4 out of 24 (17%) SW samples, ranging from 0.0033 ± 0.0050 ng/L to
0.090 ± 0.040 ng/L DHTEqs. Androgenic and estrogenic activity was higher i n pretreatment
samples compared to post-treatment in both treatment plants. In phase 1, the MDA-kb2 reporter gene assay was successfully applied to water
samples from different sources. Androgenic activity was highest in treated
wastewater. In phase 2, treatment plants proved to be effective in removing
estrogens detected in the SW samples, as the TDW samples were below the dl.
Estrogenic activity is within the ranges reported in other studies. Positive samples
were below the 0.7 ng/L proposed trigger value for health risk assessments.
Detected androgenic activity was lower in TDW samples compared to the SW
samples supplying the two treatment plants indicating that they were both effective in
removing the androgenic activity detected. Few studies have reported androgenic
activity in tap water. This study strengthens the argument for using a battery of assays when monitoring
endocrine activity as EDCs occur at low concentrations in mixtures. / Dissertation (MSc)--University of Pretoria, 2017. / School of Health Systems and Public Health (SHSPH) / MSc / Unrestricted
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