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1.
Chemosphere ; 286(Pt 3): 131842, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34388431

RESUMO

Bisphenol A (BPA) a synthetic, high production volume chemical identified as endocrine disruptor and toxic to reproduction is mainly used in the production of polycarbonate plastics, in epoxy resins, polyvinylchloride, thermal papers as color developer, and is present in a wide range of consumer goods such as food packaging materials, storage containers, and cash receipts. Due to its effects on health and legal restrictions, BPA is increasingly replaced by other bisphenols. In this study, BPA and 13 alternatives including BPS, Bisphenol F (BPF), Bisphenol B (BPB), Bisphenol C (BPC), Bisphenol Z (BPZ), Bisphenol M (BPM), Bisphenol P (BPP), Bisphenol AF (BPAF), Bisphenol FL (BPFL), Bisphenol C12 (BPC12), Tetramethylbisphenol A (tmBPA), 4,4-bisphenol (BP-4,4), and p,p-oxybisphenol were analyzed in thermal paper cash receipts (content) and migration studies were carried out in BPA-free labelled reusable plastic drinking bottles using a sensitive UHPLC-MS/MS method. The receipts contained almost only BPA and BPS, whereas BPS was found in all samples ranging at levels up to 38 µg/g. BPA was detected at low concentrations, only in one sample 11,000 µg/g were found, exceeding the EU limit of BPA in thermal paper of 0.02% per weight. In leaching solutions from the drinking bottles BPA, BPS and BPF were found at concentrations up to 0.047 µg/L BPA, 0.043 µg/L BPS, and <0.01 µg/L BPF. No other analogues were detected. However, these levels identified are far below the legal limits. In addition, a theoretical exposure assessment was conducted indicating that exposures were within the current regulatory guidelines.


Assuntos
Espectrometria de Massas em Tandem , Água , Áustria , Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão , Fenóis , Plásticos , Saliva Artificial
2.
Environ Epigenet ; 7(1): dvab011, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858639

RESUMO

4,4'-Isopropylidenediphenol (bisphenol A, BPA), a chemical substance that is widely used mainly as a monomer in the production of polycarbonates, in epoxy resins, and in thermal papers, is suspected to cause epigenetic modifications with potentially toxic consequences. Due to its negative health effects, BPA is banned in several products and is replaced by other bisphenols such as bisphenol S and bisphenol F. The present study examined the effects of BPA, bisphenol S, bisphenol F, p,p'-oxybisphenol, and the BPA metabolite BPA ß-d-glucuronide on the expression of a set of microRNAs (miRNAs) as well as long interspersed nuclear element-1 methylation in human lung fibroblast and Caco-2 cells. The results demonstrated a significant modulation of the expression of different miRNAs in both cell lines including miR-24, miR-155, miR-21, and miR-146a, known for their regulatory functions of cell cycle, metabolism, and inflammation. At concentrations between 0.001 and 10 µg/ml, especially the data of miR-155 and miR-24 displayed non-monotonous and often significant dose-response curves that were U- or bell-shaped for different substances. Additionally, BPA ß-d-glucuronide also exerted significant changes in the miRNA expression. miRNA prediction analysis indicated effects on multiple molecular pathways with relevance for toxicity. Besides, long interspersed nuclear element-1 methylation, a marker for the global DNA methylation status, was significantly modulated by two concentrations of BPA and p,p'-oxybisphenol. This pilot study suggests that various bisphenols, including BPA ß-d-glucuronide, affect epigenetic mechanisms, especially miRNAs. These results should stimulate extended toxicological studies of multiple bisphenols and a potential use of miRNAs as markers.

3.
Toxicol Sci ; 141(1): 218-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24958932

RESUMO

The risk posed by complex chemical mixtures in the environment to wildlife and humans is increasingly debated, but has been rarely tested under environmentally relevant scenarios. To address this issue, two mixtures of 14 or 19 substances of concern (pesticides, pharmaceuticals, heavy metals, polyaromatic hydrocarbons, a surfactant, and a plasticizer), each present at its safety limit concentration imposed by the European legislation, were prepared and tested for their toxic effects. The effects of the mixtures were assessed in 35 bioassays, based on 11 organisms representing different trophic levels. A consortium of 16 laboratories was involved in performing the bioassays. The mixtures elicited quantifiable toxic effects on some of the test systems employed, including i) changes in marine microbial composition, ii) microalgae toxicity, iii) immobilization in the crustacean Daphnia magna, iv) fish embryo toxicity, v) impaired frog embryo development, and vi) increased expression on oxidative stress-linked reporter genes. Estrogenic activity close to regulatory safety limit concentrations was uncovered by receptor-binding assays. The results highlight the need of precautionary actions on the assessment of chemical mixtures even in cases where individual toxicants are present at seemingly harmless concentrations.


Assuntos
Bioensaio/métodos , Conservação dos Recursos Naturais/legislação & jurisprudência , Monitoramento Ambiental , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , Animais , Monitoramento Ambiental/legislação & jurisprudência , Monitoramento Ambiental/métodos , União Europeia , Regulamentação Governamental , Humanos , Poluentes Químicos da Água/química
4.
Appl Microbiol Biotechnol ; 97(4): 1425-39, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23306641

RESUMO

Recent evidence from natural environments suggests that in addition to ammonia-oxidizing bacteria, ammonia-oxidizing archaea (AOA) affiliated with Thaumarcheota, a new phylum of the domain Archaea, also oxidize ammonia to nitrite and thus participate in the global nitrogen cycle. Besides natural environments, modern data indicate the presence of amoA-encoding archaea (AEA) in wastewater treatment plants (WWTPs). To further elucidate whether AEA in WWTPs are AOA and to clarify the role of AEA in WWTPs, this paper reviews the current knowledge on this matter for wastewater engineers and people in related fields. The initial section coveys a microbiological point of view and is particularly based upon data from AOA cultures. The later section summarizes what is currently known about AEA in relation to WWTPs. Based on the reviewed data, future research pathways are proposed in an effort to further what is known about AEA in wastewater treatment systems.


Assuntos
Archaea/enzimologia , Proteínas Arqueais/metabolismo , Oxirredutases/metabolismo , Águas Residuárias/microbiologia , Amônia/metabolismo , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , Proteínas Arqueais/genética , Oxirredução , Oxirredutases/genética , Filogenia , Águas Residuárias/química , Purificação da Água/instrumentação
5.
Arch Toxicol ; 86(5): 805-13, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22331240

RESUMO

Glyphosate (G) is the largest selling herbicide worldwide; the most common formulations (Roundup, R) contain polyoxyethyleneamine as main surfactant. Recent findings indicate that G exposure may cause DNA damage and cancer in humans. Aim of this investigation was to study the cytotoxic and genotoxic properties of G and R (UltraMax) in a buccal epithelial cell line (TR146), as workers are exposed via inhalation to the herbicide. R induced acute cytotoxic effects at concentrations > 40 mg/l after 20 min, which were due to membrane damage and impairment of mitochondrial functions. With G, increased release of extracellular lactate dehydrogenase indicative for membrane damage was observed at doses > 80 mg/l. Both G and R induced DNA migration in single-cell gel electrophoresis assays at doses > 20 mg/l. Furthermore, an increase of nuclear aberrations that reflect DNA damage was observed. The frequencies of micronuclei and nuclear buds were elevated after 20-min exposure to 10-20 mg/l, while nucleoplasmatic bridges were only enhanced by R at the highest dose (20 mg/l). R was under all conditions more active than its active principle (G). Comparisons with results of earlier studies with lymphocytes and cells from internal organs indicate that epithelial cells are more susceptible to the cytotoxic and DNA-damaging properties of the herbicide and its formulation. Since we found genotoxic effects after short exposure to concentrations that correspond to a 450-fold dilution of spraying used in agriculture, our findings indicate that inhalation may cause DNA damage in exposed individuals.


Assuntos
Dano ao DNA , Células Epiteliais/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Linhagem Celular , Bochecha , Relação Dose-Resposta a Droga , Glicina/toxicidade , Humanos , L-Lactato Desidrogenase/metabolismo , Mitocôndrias/efeitos dos fármacos , Exposição Ocupacional , Testes de Toxicidade , Glifosato
6.
Environ Pollut ; 145(2): 489-96, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16835005

RESUMO

A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl quaternary ammonium compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19ng/L for the enrichment of 500mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target compounds.


Assuntos
Desinfetantes/análise , Compostos de Amônio Quaternário/análise , Poluentes Químicos da Água/análise , Áustria , Cromatografia Líquida/métodos , Monitoramento Ambiental/métodos , Espectrometria de Massas/métodos , Abastecimento de Água
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