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1.
Anal Bioanal Chem ; 412(18): 4353-4361, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32372276

RESUMO

Recent state-of-the-art methods developed for the analysis of polar xenobiotics from different types of biological matrices usually employ liquid chromatography with mass spectrometry. However, there are limitations when a small amount of sample mass is available. For example, individual benthic invertebrates or fish tissue samples often weigh less than 100 mg (e.g., brain, liver) but are necessary to understand environmental fate and bioaccumulation dynamics. We developed ultra-fast methods based on a direct sample introduction technique. This included coupling laser diode thermal desorption with atmospheric pressure chemical ionization mass spectrometry (LDTD-APCI-MS). We then quantitated a common selective serotonin reuptake inhibitor (citalopram) in brain tissues of individual juvenile fish after in vivo exposure to environmentally relevant concentration. Two mass spectrometric methods based on low (LDTD-APCI-triple quadrupole (QqQ)-MS/MS) and high (LDTD-APCI-high-resolution product scan (HRPS)) resolutions were developed and evaluated. Individual instrument conditions were optimized to achieve an accurate and robust analytical method with minimum sample preparation requirements. We achieved very good recovery (97-108%) across the range of 1-100 ng g-1 for LDTD-APCI-HRPS. LDTD-APCI-QqQ-MS/MS showed poorer performance due to interferences from the matrix at the lowest concentration level. LDTD-APCI ionization was successfully validated for analysis of non-filtered sample extracts. Evaluation of final methods was performed for a set of real fish brain samples, including comparison of LDTD-APCI-HRPS with a previously validated LC-heated electrospray ionization-HRPS method. This new LDTD-APCI-HRPS method avoids the chromatographic step and provides important benefits such as analysis of limited sample masses, lower total sample volume (typically µL), and reduction in analysis time per sample run to a few seconds. Graphical abstract.

2.
Environ Pollut ; 242(Pt A): 417-425, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29990947

RESUMO

Unknown compounds with (anti-)androgenic activities enter the aquatic environment via municipal wastewater treatment plants (WWTPs). Progestins are well-known environmental contaminants capable of interfering with androgen receptor (AR) signaling pathway. The aim of the present study was to determine if 15 selected progestins have potential to contribute to (anti-)androgenic activities in municipal wastewaters and the respective recipient surface waters. AR-specific Chemically Activated LUciferase gene eXpression bioassay in agonistic (AR-CALUX) and antagonistic (anti-AR-CALUX) modes and liquid chromatography tandem atmospheric pressure chemical ionization/atmospheric photoionization with hybrid quadrupole/orbital trap mass spectrometry operated in high resolution product scan mode (LC-APCI/APPI-HRPS) methods were used to assess (anti-)androgenic activity and to detect the target compounds, respectively. The contribution of progestins to (anti-)androgenic activities was evaluated by means of a biologically and chemically derived toxicity equivalent approach. Androgenic (0.08-59 ng/L dihydrotestosterone equivalents - DHT EQs) and anti-androgenic (2.4-26 µg/L flutamide equivalents - FLU EQs) activities and progestins (0.19-75 ng/L) were detected in selected aquatic environments. Progestins displayed androgenic potencies (0.01-0.22 fold of dihydrotestosterone) and strong anti-androgenic potencies (9-62 fold of flutamide). Although they accounted to some extent for androgenic (0.3-29%) and anti-androgenic (4.6-27%) activities in influents, the progestins' contribution to (anti-)androgenic activities was negligible (≤2.1%) in effluents and surface waters. We also tested joint effect of equimolar mixtures of target compounds and the results indicate that compounds interact in an additive manner. Even if progestins possess relatively strong (anti-)androgenic activities, when considering their low concentrations (sub-ng/L to ng/L) it seems unlikely that they would be the drivers of (anti-)androgenic effects in Czech aquatic environments.


Assuntos
Antagonistas de Androgênios/química , Progestinas/química , Poluentes Químicos da Água/química , Androgênios , Bioensaio/métodos , Águas Residuárias/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise
3.
Anal Chim Acta ; 1022: 53-60, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-29729738

RESUMO

A simple, robust and effective extraction procedure for the determination of 74 pharmaceuticals in different fish tissues by ultrasensitive high performance liquid chromatography with electrospray high resolution product scan (HPLC-ESI-HRPS) was developed and validated. Different extraction solvent mixtures were tested to achieve the highest recoveries of the selected analytes, to minimize the influence of a complex matrix and to reduce the total analysis time as well as cost of analysis. A mixture of acetonitrile + isopropanol (3:1 v/v) acidified with 0.1% formic acid was the best extraction solvent among the five solvents tested for most of the tissues with the exception of plasma samples, where only acidified acetonitrile exhibited the best performance. The developed method was validated at three concentration levels (5, 20 and 50 ng g-1) in five different fish tissues (liver, kidney, brain, muscle and plasma). Most of the target analytes were extracted with a recovery between 60 and 130%. Very low limits of quantification (LOQs) were obtained for the majority of the pharmaceuticals in all of the studied matrices. The developed analytical method was successfully applied for the analysis of common carp (Cyprinus carpio) originating from the waste water effluent-dominated pond Cezarka (Czech Republic). The results confirmed the importance of multi-tissue analysis to obtain complex information on the distribution of pharmaceuticals in fish.


Assuntos
Biota , Carpas , Fracionamento Químico/métodos , Resíduos de Drogas/análise , Resíduos de Drogas/isolamento & purificação , 2-Propanol/química , Acetonitrilos/química , Animais , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Reprodutibilidade dos Testes
4.
Water Res ; 137: 64-71, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29544204

RESUMO

Vast numbers of xenobiotics are known still to be present in treated municipal wastewater treatment plant (WWTP) effluents. Some of these possess endocrine-disrupting potency and pose risks for exposed aquatic animals. We searched for 17 potential environmental contaminants having affinity to the progesterone receptor. Relative potency values of these progesterone receptor-active chemicals were obtained. On the basis of relative potencies and measured environmental concentrations, the contribution of progestins to measured progestagenic activities was evaluated. Wastewaters (influent and effluent) and surrounding surface waters (upstream and downstream) at six municipal WWTPs were screened using instrumental chemical analysis and in vitro reporter gene bioassay. We showed the presence of target compounds and (anti-)progestagenic activities in municipal wastewater and surface water. Nine and seven progestins were identified in influent and effluent wastewaters, respectively. Only two compounds, progesterone and medroxyprogesterone were found in surface waters. Progestagenic agonistic activities in influents were partially masked by strong anti-progestagenic activities that were detected in all influents and ranged from 2.63 to 83 ng/L of mifepristone equivalents (EQs). Progestagenic activities were detected in all effluents and ranged from 0.06 to 0.47 ng/L of reference compound ORG 2058 EQs (a synthetic progestin equivalents), thus indicating incomplete removal of progestins during wastewater treatment processing. This activity poses a continuing risk for the aquatic environment. By contrast, anti-progestagenic activities showed better removal efficiency in WWTPs compared to progestagenic agonistic activities. Anti-progestagenic activities were found in only three of six effluents and ranged from 0.26 to 2.1 ng/L mifepristone EQs. We explained most of the progestagenic activity in municipal WWTP effluents by the presence of synthetic progestins and progesterone, which contributed 65-96% of such activity in samples where no antagonistic activity was found. The progestins medroxyprogesterone acetate, megestrol acetate and progesterone contributed most to the progestagenic activity detected in municipal effluents. Anti-progestagenic activities were found in some municipal effluents, but no causative agents were revealed because two analysed selective progesterone receptor modulators (SPRMs) with anti-progestagenic activities, mifepristone and ulipristal acetate, were not present in the effluents.


Assuntos
Progesterona/toxicidade , Progestinas/toxicidade , Águas Residuárias/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Linhagem Celular , República Tcheca , Ecotoxicologia/métodos , Monitoramento Ambiental , Humanos , Medroxiprogesterona/análise , Medroxiprogesterona/toxicidade , Mifepristona/toxicidade , Progesterona/análise , Progestinas/análise , Receptores de Progesterona/metabolismo , Eslováquia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise
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