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1.
Aquat Toxicol ; 231: 105719, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33360234

RESUMEN

Numerous environmental pollutants have the potential to accumulate in sediments, and among them are endocrine-disrupting chemicals (EDCs). It is well documented that water-borne exposure concentrations of some potent EDCs, more specifically estrogenic- active compounds (ECs), can impair the reproduction of fish. In contrast, little is known about the bioavailability and effects of sediment-associated ECs on fish. Particularly, when sediments are disturbed, e.g., during flood events, chemicals may be released from the sediment and become bioavailable. The main objectives of this study were to evaluate a) whether ECs from the sediment become bioavailable to fish when the sediment is suspended, and b) whether such exposure leads to endocrine responses in fish. Juvenile rainbow trout (Oncorhynchus mykiss) were exposed over 21 days to constantly suspended sediments in the following treatments: i) a contaminated sediment from the Luppe River, representing a "hotspot" for EC accumulation, ii) a reference sediment (exhibiting only background contamination), iii) three dilutions, 2-, 4- and 8-fold of Luppe sediment diluted with the reference sediment, and iv) a water-only control. Measured estrogenic activity using in vitro bioassays as well as target analysis of nonylphenol and estrone via LC-MS/MS in sediment, water, fish plasma, as well as bile samples, confirmed that ECs became bioavailable from the sediment during suspension. ECs were dissolved in the water phase, as indicated by passive samplers, and were readily taken up by the exposed trout. An estrogenic response of fish to Luppe sediment was indicated by increased abundance of transcripts of typical estrogen responsive genes, i.e. vitelline envelope protein α in the liver and vitellogenin induction in the skin mucus. Altered gene expression profiles of trout in response to suspended sediment from the Luppe River suggest that in addition to ECs a number of other contaminants such as dioxins, polychlorinated biphenyls (PCBs) and heavy metals were remobilized during suspension. The results of the present study demonstrated that sediments not only function as a sink for ECs but can turn into a significant source of pollution when sediments are resuspended as during flood-events. This highlights the need for sediment quality criteria considering bioavailability sediment-bound contaminants in context of flood events.


Asunto(s)
Estrógenos/toxicidad , Sedimentos Geológicos/química , Oncorhynchus mykiss/metabolismo , Animales , Disponibilidad Biológica , Exposición a Riesgos Ambientales , Femenino , Ontología de Genes , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Vitelogeninas/metabolismo , Contaminantes Químicos del Agua/toxicidad
2.
Water Res ; 170: 115338, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31841769

RESUMEN

Decentralized drinking water purification complements water supply in areas with unreliable or absent infrastructure. The exacerbating consequences of climate change in form of droughts and floods force remote households to tap various water sources. Hence, household-based processes must be versatile to cope with e.g. contaminated ground water and turbid surface waters. Purification at household level must be self-sustaining in order to enable independence from continuous supply of power and consumables. In this study, we design a process accordingly and we prove its technical feasibility on pilot scale. The two-step process utilizes gravity-driven ultrafiltration and activated carbon adsorption to purify water, whereas the process regeneration is accomplished by combining Temperature Enhanced Backwash and Temperature Swing Adsorption to clean the membrane and adsorber, respectively. We obtained stable operation over >40 days with a sustained flowrate of ∼5 Lh-1 and consistent product quality (turbidity ≤0.2 NTU) for all relevant water matrices: synthetic ground water, river water and even secondary effluent. We achieved a high removal of the spiked model micropollutant amitrole, environmental endocrine disruptors and bulk dissolved organics of ∼93%, >65% and ∼69%, respectively, at the optimal water recovery for river water of ∼80%. In-situ regeneration promises long-term, self-sufficient operation without exhaustion.


Asunto(s)
Agua Potable , Purificación del Agua , Adsorción , Carbón Orgánico , Ultrafiltración , Abastecimiento de Agua
3.
Environ Pollut ; 257: 113636, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31780365

RESUMEN

Little is known about sediment-bound exposure of fish to endocrine disrupting chemicals (EDC) under field conditions. This study aimed to investigate potential routes of EDC exposure to fish and whether sediment-bound contaminants contribute towards exposure in fish. Tench (Tinca tinca) and roach (Rutilus rutilus) as a benthic and pelagic living fish species, respectively, were sampled at the Luppe River, previously described as a "hotspot" for accumulation of EDC in sediment. A field reference site, the Laucha River, additionally to fish from a commercial fish farm as reference were studied. Blackworms, Lumbriculus variegatus, which are a source of prey for fish, were exposed to sediment of the Luppe River and estrogenic activity of worm tissue was investigated using in vitro bioassays. A 153-fold greater estrogenic activity was measured using in vitro bioassays in sediment of the Luppe River compared the Laucha River. Nonylphenol (NP; 22 mg/kg) was previously identified as one of the main drivers of estrogenic activity in Luppe sediment. Estrogenic activity of Luppe exposed worm tissue (14 ng 17ß-estradiol equivalents/mg) indicated that food might act as secondary source to EDCs. While there were no differences in concentrations of NP in plasma of tench from the Luppe and Laucha, vitellogenin, a biomarker for exposure to EDCs, was induced in male tench and roach from the Luppe River compared to both the Laucha and cultured fish by a factor of 264 and 90, respectively. However, no histological alterations in testis of these fish were observed. Our findings suggest that sediments substantially contribute to the overall EDC exposure of both benthic and pelagic fish but that the exposure did not impact gonad status of the fish.


Asunto(s)
Disruptores Endocrinos , Estrógenos , Peces , Sedimentos Geológicos , Contaminantes Químicos del Agua , Animales , Disruptores Endocrinos/análisis , Estrógenos/análisis , Estrógenos/toxicidad , Agua Dulce/química , Sedimentos Geológicos/química , Masculino , Ríos
4.
Water Res ; 161: 540-548, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31233966

RESUMEN

Studies worldwide have demonstrated through in vitro bioassays and chemical analysis that endocrine-disrupting chemicals (EDCs) can accumulate in river sediments. However, remobilization of sediment-bound EDCs due to bioturbation or re-suspension during flood events remains poorly understood. The aim of this study was to evaluate the bioavailability of EDCs, more specifically estrogenic compounds (EC), from sediment under turbulent conditions using a passive sampling approach. Sediment was sampled along the Luppe River, Germany, previously described as a "hotspot" for ECs. The concentration of target ECs and estrogenic activity were investigated using chemical analysis (LC MS/MS) in addition to a novel screening tool (planar Yeast Estrogen Screen; p-YES) that utilizes high performance thin-layer chromatography plates in combination with an in vitro bioassay (YES). Estrone (50%, E1) and nonylphenol (35%, NP) accounted for the majority of estrogenic activity reported of up to 20 ±â€¯2.4 µg E2 equivalents per kg dry weight in the Luppe sediments. Two types of passive samplers (polar organic chemical integrative sampler (POCIS) and Chemcatcher) were used to investigate the bioavailability of ECs from suspended sediment under laboratory conditions. NP, E1, E2 and ethynylestradiol (EE2) were remobilized from Luppe sediment when subjected to turbulent conditions, such as in a flood event, and were readily bioavailable at ecotoxicologically relevant concentrations (NP 18 µg/L, E1 14 ng/L, E2 0.2 ng/L, EE2 0.5 ng/L).


Asunto(s)
Disruptores Endocrinos , Contaminantes Químicos del Agua , Disponibilidad Biológica , Monitoreo del Ambiente , Estrógenos , Inundaciones , Sedimentos Geológicos , Alemania , Ríos , Espectrometría de Masas en Tándem
5.
Environ Sci Eur ; 29(1): 23, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28752018

RESUMEN

Protecting our water resources in terms of quality and quantity is considered one of the big challenges of the twenty-first century, which requires global and multidisciplinary solutions. A specific threat to water resources, in particular, is the increased occurrence and frequency of flood events due to climate change which has significant environmental and socioeconomic impacts. In addition to climate change, flooding (or subsequent erosion and run-off) may be exacerbated by, or result from, land use activities, obstruction of waterways, or urbanization of floodplains, as well as mining and other anthropogenic activities that alter natural flow regimes. Climate change and other anthropogenic induced flood events threaten the quantity of water as well as the quality of ecosystems and associated aquatic life. The quality of water can be significantly reduced through the unintentional distribution of pollutants, damage of infrastructure, and distribution of sediments and suspended materials during flood events. To understand and predict how flood events and associated distribution of pollutants may impact ecosystem and human health, as well as infrastructure, large-scale interdisciplinary collaborative efforts are required, which involve ecotoxicologists, hydrologists, chemists, geoscientists, water engineers, and socioeconomists. The research network "project house water" consists of a number of experts from a wide range of disciplines and was established to improve our current understanding of flood events and associated societal and environmental impacts. The concept of project house and similar seed fund and boost fund projects was established by the RWTH Aachen University within the framework of the German excellence initiative with support of the German research foundation (DFG) to promote and fund interdisciplinary research projects and provide a platform for scientists to collaborate on innovative, challenging research. Project house water consists of six proof-of-concept studies in very diverse and interdisciplinary areas of research (ecotoxicology, water, and chemical process engineering, geography, sociology, economy). The goal is to promote and foster high-quality research in the areas of water research and flood-risk assessments that combine and build off-laboratory experiments with modeling, monitoring, and surveys, as well as the use of applied methods and techniques across a variety of disciplines.

6.
J Dtsch Dermatol Ges ; 14(12): 1237-1247, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27992136

RESUMEN

HINTERGRUND UND FRAGESTELLUNG: Hautveränderungen bei rheumatoider Arthritis (RA) sind nur in wenigen Studien an größeren Patientenkollektiven untersucht. Deshalb sollen hier die aktuelle Prävalenz und das Spektrum an Hautveränderungen bei RA unter Berücksichtigung von Krankheitsaktivitäts-Scores, Anti-CCP-Antikörpern sowie neueren medikamentösen Therapien erfasst werden. PATIENTEN UND METHODIK: Zwischen November 2006 und Juli 2007 wurden prospektiv 214 Patienten, die im Funktionsbereich Rheumatologie mit RA behandelt wurden, erfasst. ERGEBNISSE: Bei 27,5 % der Untersuchten wurden RA-assoziierte Hautveränderungen beobachtet, wobei es sich fast ausschließlich um Rheumaknoten handelte. Signifikant gehäuft traten Rheumaknoten bei längerer Erkrankungsdauer, Nachweis von Rheumafaktoren und Anti-CCP-Antikörpern, aber auch unter Gabe von Leflunomid und TNFα-Blockern auf. Vergleichsweise niedrige Prävalenzen wurden hingegen für die "palisadenförmige neutrophile und granulomatöse Dermatitis" und die "rheumatoide Vaskulitis" ermittelt. SCHLUSSFOLGERUNGEN: Trotz zunehmend frühzeitiger Therapie der RA und dem Einsatz neuerer Medikamente ist die Prävalenz von Rheumaknoten als wichtigste Manifestation der RA am Hautorgan hoch. Deren verstärkte Ausbildung unter Leflunomid und TNFα-Blockern könnte ein Hinweis dafür sein, dass bei der Entstehung von Rheumaknoten eine pathogenetische Wegstrecke eine Rolle spielt, die von den Therapeutika nur unzureichend beeinflusst wird. Hingegen scheinen die palisadenförmige neutrophile und granulomatöse Dermatitis und die "rheumatoide Vaskulitis" durch neuere Medikamente besser beeinflussbar zu sein.

7.
J Dtsch Dermatol Ges ; 14(12): 1237-1246, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27886444

RESUMEN

BACKGROUND AND OBJECTIVE: There have only been few studies examining rheumatoid arthritis (RA)-related skin manifestations in larger patient populations. Herein, we present current data on the prevalence and spectrum of cutaneous lesions in RA, addressing disease activity scores, anti-CCP antibodies as well as novel pharmacological approaches. PATIENTS AND METHODS: Between November 2006 and July 2007, 214 patients with RA treated at the Division of Rheumatology, University Hospital Jena, Germany, were prospectively examined. RESULTS: 27.5 % of patients exhibited RA-related skin manifestations, almost all of which were rheumatoid nodules. These lesions occurred significantly more frequently in patients with longstanding disease, those testing positive for rheumatoid factor and anti-CCP-antibodies, as well as individuals on leflunomide and TNF-alpha antagonists. Comparatively lower prevalence rates were observed for palisading neutrophilic and granulomatous dermatitis and rheumatoid vasculitis. CONCLUSIONS: Despite increasingly early treatment of RA and use of novel pharmacological agents, there is a high prevalence of rheumatoid nodules, which represent the most common cutaneous manifestation in RA. The higher prevalence of rheumatoid nodules in patients on leflunomide and TNF-alpha antagonists might be an indication that pharmacological treatment has only limited effects on their formation, possibly due to pathogenetic pathways that are only inadequately affected by drug therapies. By contrast, palisading neutrophilic and granulomatous dermatitis and rheumatoid vasculitis appear to respond better to novel pharmacological agents.


Asunto(s)
Artritis Reumatoide/diagnóstico , Artritis Reumatoide/epidemiología , Nódulo Reumatoide/diagnóstico , Nódulo Reumatoide/epidemiología , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/inmunología , Causalidad , Comorbilidad , Femenino , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Nódulo Reumatoide/inmunología , Factores de Riesgo , Enfermedades de la Piel/inmunología
8.
Environ Sci Pollut Res Int ; 22(22): 17330-42, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25936831

RESUMEN

Mercury (Hg) contamination is a global issue due to its anthropogenic release, long-range transport, and deposition in remote areas. In Kejimkujik National Park and National Historic Site, Nova Scotia, Canada, high concentrations of total mercury (THg) were found in tissues of yellow perch (Perca flavescens). The aim of this study was to evaluate a possible relationship between THg concentrations and the morphology of perch liver as a main site of metal storage and toxicity. Yellow perch were sampled from five lakes known to contain fish representing a wide range in Hg concentrations in fall 2013. The ultrastructure of hepatocytes and the distribution of Hg within the liver parenchyma were analyzed by transmission electron microscopy (TEM) and electron energy loss spectrometry (EELS). The relative area of macrophage aggregates (MAs) in the liver was determined using image analysis software and fluorescence microscopy. No relation between general health indicators (Fulton's condition index) and THg was observed. In line with this, TEM examination of the liver ultrastructure revealed no prominent pathologies related to THg accumulation. However, a morphological parameter that appeared to increase with muscle THg was the relative area of MAs in the liver. The hepatic lysosomes appeared to be enlarged in samples with the highest THg concentrations. Interestingly, EELS analysis revealed that the MAs and hepatic lysosomes contained Hg.


Asunto(s)
Hígado/citología , Hígado/metabolismo , Mercurio/metabolismo , Mercurio/toxicidad , Percas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente , Lagos/química , Hígado/efectos de los fármacos , Hígado/ultraestructura , Músculos/efectos de los fármacos , Músculos/metabolismo , Nueva Escocia , Estaciones del Año
9.
Mol Ecol ; 21(18): 4646-62, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22861488

RESUMEN

The cultivation of Lepidoptera-resistant Bt-maize may affect nontarget butterflies. We assessed the risk posed by event MON89034 × MON88017 (expressing Cry1A.105 and Cry2Ab2 against corn borers) to nontarget Lepidoptera. Using the small tortoiseshell Aglais urticae, a butterfly species common in central Europe, as a test organism we (i) assessed the toxicity of Bt-maize pollen on butterfly larvae; (ii) measured pollen deposition on leaves of the host plant Urtica dioica; (iii) mapped the occurrence and distribution of host plants and larvae in two arable landscapes in Germany during maize anthesis; and (iv) described the temporal occurrence of a 1-year population of A. urticae. (i) Larvae-fed 200 Bt-maize pollen grains/cm(2) had a reduced feeding activity. Significant differences in developmental time existed at pollen densities of 300 Bt-maize pollen grains/cm(2) and in survival at 400 grains/cm(2). (ii) The highest pollen amount found was 212 grains/cm(2) at the field margin. Mean densities were much lower. (iii) In one region, over 50% of A. urticae nests were located within 5 m of a maize field, while in the other, all nests were found in more than 25 m distance to a maize field. (iv) The percentage of larvae developing during maize anthesis was 19% in the study area. The amount of pollen from maize MON89034 × MON88017 found on host plants is unlikely to adversely affect a significant proportion of larvae of A. urticae. This paper concludes that the risk of event MON89034 × MON88017 to populations of this species is negligible.


Asunto(s)
Mariposas Diurnas/efectos de los fármacos , Herbivoria , Plantas Modificadas Genéticamente/toxicidad , Zea mays/genética , Animales , Bacillus thuringiensis , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/toxicidad , Endotoxinas/toxicidad , Alemania , Proteínas Hemolisinas/toxicidad , Larva/efectos de los fármacos , Polen/toxicidad , Medición de Riesgo , Zea mays/toxicidad
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