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1.
Ecotoxicol Environ Saf ; 181: 472-480, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228823

RESUMO

Heavy metal pollution is one of the most widespread and complex environmental issues globally, posing a great threat to the ecosystem as well as human health. Bioremediation through heavy metal-resistant bacteria (HMRB) is currently the most promising technology to address this issue. To obtain HMRB to remediate heavy metal pollution potentially, 15 culturable HMRB strains were isolated from the sludge samples of an electroplating wastewater treatment plant (EWWTP), which belonged to the Bacillus, Shewanella, Lysinibacillus, and Acinetobacter genera. Their maximum tolerance concentrations to Cu2+, Ni2+, Mn2+, Co2+, and Cr2O72- were 40 mM, 10 mM, 200 mM, 40 mM, and 10 mM, respectively, and strain Mn1-4 showed much higher Mn2+ tolerance and removal effectiveness (3.355 g/L) than previously published reports. Moreover, multiple heavy metal-resistant genotypes and phenotypes were identified among these strains, of which strain Co1-1 carried the most of resistant gene sequences (10) and exhibited resistance to 7 categories of heavy metals, and the co-occurrence of heavy metal and antibiotic resistance were clearly observed in strain Ni1-3. In addition, flanked insert sequence (IS) elements on the heavy metal resistant genes (HMRGs) suggested that horizontal gene transfer (HGT) events may have resulted in multiple heavy metal resistance phenotypes and genotypes in these strains, and IS982 family transposase was presumed to result in the high Ni2+ tolerance in strain Ni1-3. This study expands our understanding of bacterial heavy metal resistance and provides promising candidates for heavy metal bioremediation.


Assuntos
Bactérias/metabolismo , Galvanoplastia , Metais Pesados/metabolismo , Águas Residuárias/microbiologia , Poluentes Químicos da Água/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Farmacorresistência Bacteriana Múltipla/genética , Transferência Genética Horizontal , Humanos , Metais Pesados/farmacologia , Esgotos/química , Esgotos/microbiologia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacologia
2.
An Acad Bras Cienc ; 91(2): e20180474, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241700

RESUMO

This study investigated the physiological effects of a pesticide based on Bacillus thuringiensis (Dipel-WP®) added in the water and diet of Piaractus mesopotamicus during 24 and 48 h. It was added 0.13 g of de B. thuringiensis per kg of commercial feed; and for the fish subjected to the biopesticide in the water of the tanks, it was added 0.13 g/L of the biopesticide. Plasma levels of sodium, chloride, potassium, cholesterol, glucose, triglycerides, cortisol, total protein, alanine aminotransferase (ALT), aspartate aminotransferase (AST), hematocrit, hemoglobin, erythrocytes number, mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC), number of thrombocytes and leukocytes were determined. Cortisol, lactate, glucose, total protein, cholesterol, triglycerides, ALT, AST, sodium, potassium, hematocrit, hemoglobin, MCV, number of erythrocytes, leukocytes, lymphocytes, eosinophils and PAS-positive granular leukocytes suffered alterations derived from the addition of B. thuringiensis in water and diet of the fish. The toxicity of the concentrations of biopesticide in short-term exposure in water and diet of the fish led to blood alterations (increase or decrease). Therefore, care must be taken to avoid a possible prolonged contamination in the tanks of fish farming by agricultural pollution based on B. thuringiensis.


Assuntos
Bacillus thuringiensis/química , Characidae/sangue , Praguicidas/farmacologia , Poluentes Químicos da Água/farmacologia , Animais , Characidae/classificação , Fatores de Tempo
3.
Environ Monit Assess ; 191(7): 469, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31243556

RESUMO

Sapanca Lake is important as a source of drinking water. In this study, we aimed to detect the bacterial quality, the frequency of bacterial antibiotic and heavy metal resistance, and bioindicator bacteria in the water samples taken from Sapanca Lake in the period between 2008 and 2010. The resistance of bacterial isolates to certain antibiotics and heavy metal salts was investigated using disc diffusion and minimum inhibitory concentration techniques. Bacterial metabolic reactions were tested using the VITEK 2 Compact 30 micro identification system for identification of cultivable bacteria. Twenty-seven bacteria species belonging to three classes-Gammaproteobacteria, Bacilli, Flavobacteria-were recorded for the first time in Sapanca Lake. The highest indicator bacteria were recorded as 71 ± 3.1 × 104 CFU/100 ml in the summer season. The highest bacterial resistance was recorded as 90.47% against vancomycin in a total of 84 strains. Ampicillin (88.10%) and amoxicillin-clavulanate (64.29%) followed them. The resistance varied between 10.71 and 59.52% against cefuroxime, kanamycin, aztreonam, ceftazidime, cefotaxime, and oxacillin. The highest frequency against heavy metal salts was recorded as 74.19% against NiCl2. The heavy metal resistance against Cu, Zn, Hg, and Cd detected as 52.38%, 46.42%, 33.33%, and 26.19%, respectively. The results showed that the occurrence of heavy metals and antibiotic sources in Sapanca Lake induced a tolerance in bacteria for the metal salts and antibiotic derivatives tested. The fluctuations in the indicator bacteria and the occurrence of pathogenic bacteria also showed the possibility that the coastal areas of Sapanca Lake had been exposed to contamination due to inadequate sewage treatment.


Assuntos
Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/fisiologia , Monitoramento Ambiental/métodos , Metais Pesados/farmacologia , Bacillus/isolamento & purificação , Bactérias/isolamento & purificação , Água Potável/química , Água Potável/microbiologia , Flavobacteriaceae/isolamento & purificação , Gammaproteobacteria/isolamento & purificação , Lagos , Testes de Sensibilidade Microbiana , Turquia , Poluentes Químicos da Água/farmacologia , Poluição da Água
4.
Environ Sci Pollut Res Int ; 26(18): 18470-18483, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31049859

RESUMO

Wastewater contains subinhibitory concentrations of different micropollutants such as antibiotics that create selective pressure on bacteria. This phenomenon is also caused by insufficient wastewater treatment technology leading to the development and spread of antibiotic-resistant bacteria and resistance genes into the environment. Therefore, this work focused on monitoring of antibiotic-resistant coliform bacteria and enterococci in influent and effluent wastewaters taken from the second biggest wastewater treatment plant (Petrzalka) in the capital of Slovakia during 1 year. Antibiotic-resistant strains were isolated, identified, and characterized in terms of susceptibility and biofilm production. All of 27 antibiotic-resistant isolates were identified mainly as Morganella morganii, Citrobacter spp., and E. coli. Multidrug-resistance was detected in 58% of isolated strains. All tested isolates could form biofilm; two strains were very strong producers, and 74% formed biofilm by strong intensity. The flow rate of the influent wastewater had a more significant impact on the number of studied bacteria than the temperature. Graphical abstract.


Assuntos
Farmacorresistência Bacteriana , Enterococcus/isolamento & purificação , Escherichia coli/isolamento & purificação , Águas Residuárias/microbiologia , Purificação da Água/métodos , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Farmacorresistência Bacteriana/genética , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Estações do Ano , Eslováquia , Águas Residuárias/química , Poluentes Químicos da Água/farmacologia
5.
Environ Health Prev Med ; 24(1): 36, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101002

RESUMO

BACKGROUND: Melanin is detectable in various sense organs including the skin in animals. It has been reported that melanin adsorbs toxic elements such as mercury, cadmium, and lead. In this study, we investigated the adsorption of molybdenum, which is widely recognized as a toxic element, by melanin. METHODS: Molybdenum level of the mouse skin was measured by inductively coupled plasma mass spectrometry. The pigmentation level of murine skin was digitalized as the L* value by using a reflectance spectrophotometer. An in vitro adsorption assay was performed to confirm the interaction between molybdenum and melanin. RESULTS: Our analysis of hairless mice with different levels of skin pigmentation showed that the level of molybdenum increased with an increase in the level of skin pigmentation (L* value). Moreover, our analysis by Spearman's correlation coefficient test showed a strong correlation (r = - 0.9441, p < 0.0001) between L* value and molybdenum level. Our cell-free experiment using the Langmuir isotherm provided evidence for the adsorption of molybdenum by melanin. The maximum adsorption capacity of 1 mg of synthetic melanin for molybdenum was 131 µg in theory. CONCLUSION: Our in vivo and in vitro results showed a new aspect of melanin as an adsorbent of molybdenum.


Assuntos
Melaninas/química , Molibdênio/química , Poluentes Químicos da Água/química , Adsorção , Animais , Melaninas/metabolismo , Camundongos , Camundongos Pelados , Camundongos Transgênicos , Molibdênio/metabolismo , Molibdênio/farmacologia , Pele/química , Pele/efeitos dos fármacos , Pigmentação da Pele/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/farmacologia
6.
Environ Sci Process Impacts ; 21(6): 988-998, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31093631

RESUMO

The contamination of surface water and ground water by human activities, such as fossil fuel extraction and agriculture, can be difficult to assess due to incomplete knowledge of the chemicals and chemistry involved. This is particularly true for the potential contamination of drinking water by nearby extraction of oil and/or gas from wells completed by hydraulic fracturing. A case that has attracted considerable attention is unconventional natural gas extraction in Susquehanna County, Pennsylvania, particularly around Dimock, Pennsylvania. We analyzed surface water and groundwater samples collected throughout Susquehanna County with complementary biological assays and high-resolution mass spectrometry. We found that Ah receptor activity was associated with proximity to impaired gas wells. We also identified certain chemicals, including disclosed hydraulic fracturing fluid additives, in samples that were either in close proximity to impaired gas wells or that exhibited a biological effect. In addition to correlations with drilling activity, the biological assays and high-resolution mass spectrometry detected substances that arose from other anthropogenic sources. Our complementary approach provides a more comprehensive picture of water quality by considering both biological effects and a broad screening for chemical contaminants.


Assuntos
Monitoramento Ambiental/métodos , Fraturamento Hidráulico , Poluentes Químicos da Água/análise , Bioensaio , Linhagem Celular Tumoral , Cromatografia Líquida , Água Doce/análise , Humanos , Espectrometria de Massas , Campos de Petróleo e Gás , Pennsylvania , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Esteroides/metabolismo , Poluentes Químicos da Água/farmacologia
7.
Environ Pollut ; 250: 274-283, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30999204

RESUMO

MicroRNAs (miRNAs) are a class of small non-coding RNA that control multiple biological processes through negative post-transcriptional regulation of gene expression. Recently a role of miRNAs in the response of aquatic organisms to environmental toxicants emerged. Toxicant-induced changes in miRNA expression might then represent novel biomarkers to evaluate the health status of these organisms. In this study, we aimed to identify the miRNA repertoire in the liver of the European eel Anguilla anguilla and to compare their differential expression between a polluted site located in the Gironde Estuary and a pristine site in Arcachon Bay (France). A total of 299 mature miRNAs were identified. In polluted water, 19 miRNAs were up-regulated and 22 were down-regulated. We predicted that these differentially expressed miRNAs could target 490 genes that were involved in ribosome biogenesis, response to hormones, response to chemical and chromatin modification. Moreover, we observed only few examples (29) of negative correlation between the expression levels of miRNAs and their targets suggesting that, in the system studied, miRNAs might not only regulate gene expression directly by degrading mRNA but also by inhibiting protein translation or by regulating other epigenetic processes. This study is the first example of in situ investigation of the role of miRNAs in the response of a fish species to water quality. Our findings provide new insights into the involvement of epigenetic mechanisms in the response of animals chronically exposed to pollution and pave the way for the utilization of miRNAs in aquatic ecotoxicology.


Assuntos
Anguilla/genética , Biomarcadores Ambientais/genética , MicroRNAs/genética , Poluentes Químicos da Água/análise , Animais , Estuários , França , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Fígado/metabolismo , Poluentes Químicos da Água/farmacologia
8.
Ecotoxicol Environ Saf ; 177: 25-31, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30954009

RESUMO

Pesticides and medications have adverse effects in non-target organisms that can lead to different modes of action (MOAs). However, no study has been performed to compare the MOAs between different levels of aquatic species. In this study, theoretical equations of interspecies relationship and excess toxicity have been developed and used to investigate the MOAs among fish, Daphnia magna, Tetrahymena pyriformis and Vibrio fischeri for pesticides and medications. The analysis on the interspecies correlation and excess toxicity suggested that fungicides, herbicides and medications share the similar MOAs among the four species. On the other hand, insecticides share different MOAs among the four species. Exclusion of insecticides from the interspecies correlation can significantly improve regression coefficient. Interspecies relationship is dependent not only on the difference in interaction of chemicals with the target receptor(s), but also on the difference in bio-uptake between two species. The difference in physiological structures will result in the difference in bioconcentration potential between two different trophic levels of organisms. Increasing of molecular size or hydrophobicity will increase the toxicity to higher level of aquatic organisms; on the other hand, chemical ionization will decrease the toxicity to higher level organisms. Hydrophilic compounds can more easily pass through cell membrane than skin or gill, leading to greater excess toxicity to Vibrio fischeri, but not to fish and Daphnia magna.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Animais , Daphnia/efeitos dos fármacos , Peixes/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Praguicidas/metabolismo , Praguicidas/farmacologia , Tetrahymena pyriformis/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/farmacologia
9.
Chemosphere ; 225: 126-134, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30870629

RESUMO

Metals and organophosphorous pesticides commonly co-occur in marine environment, but the effect of their mixtures on non-target organisms is still poorly understood. This study investigated the combined effect of the essential metal copper (Cu) and organophosphorous pesticide chlorpyrifos (Chp) in mussels (Mytilus galloprovincialis) after short-term exposure to their sublethal concentrations. Mussels were exposed for four days to 5 and 15 µg L-1 Cu and 0.05 and 5 µg L-1 Chp, and to their binary mixtures. The investigated biomarkers, namely acetylcholinesterase activity (AChE), glutathione S-transferase activity (GST), metallothioneins content (MTs) and lipid peroxide levels (LPO) displayed unspecific and inconsistent response patterns that varied depending on the concentration of chemicals and composition of mixtures. The exposure to Cu or Chp alone did not induce AChE activity changes, whereas only Cu provoked a significant GST activity increase. Exposure to lower and higher concentration of Chp resulted in MTs content and LPO level increase, respectively. Response of biomarkers to mixtures was generally inconsistent. Data integration by IBR index and PCA revealed different stress levels for given exposure conditions, but no explicit differentiation between single and joint exposures was found. The present results showed that low and environmentally relevant concentrations of Cu and Chp in mixtures may result in a detectable biological response, stressing the need for further investigation of joint effects of widespread marine contaminants in sentinel organisms.


Assuntos
Clorpirifos/farmacologia , Cobre/farmacologia , Mytilus/efeitos dos fármacos , Mytilus/metabolismo , Poluentes Químicos da Água/farmacologia , Animais , Biomarcadores/metabolismo , Interações de Medicamentos
10.
Chemosphere ; 224: 93-102, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30818199

RESUMO

In their environments, aquatic organisms are simultaneously exposed to mixtures of several endocrine disrupting compounds, including hormones. However, most of the toxicity studies so far focused on effects of single contaminants. The available information on the potential toxicity of combined hormones on microalgae is extremely limited. For these reasons the aim of this study was to evaluate the individual and mixture effect of estrone (E1), ß-estradiol (E2), estriol (E3), 17-α-ethinylestradiol (EE2), progesterone (PRO), 5-pregnen-3ß-ol-20-one (PRE), levonorgestrel (LG) and testosterone (TST) on Chlorella vulgaris and Scenedesmus armatus. Green algae cells were exposed to different concentrations (0.1-100 mg L-1) of hormones for 14 days. Biomass in the form of dry weight and chlorophyll a was examined. The decreasing order of toxicity (based on EC50, 14d) to Chlorella vulgaris and Scenedesmus armatus was: EE2>PRO > E2>PRE > TST > E3>LG > E1 and EE2>PRO > TST > E2>PRE > LG > E1>E3, respectively. Chlorella vulgaris was more sensitive to the effects of hormones than Scenedesmus armatus. Although mixed hormones were more toxic to green algae than single hormones, in the ecosystem mixtures can pose higher ecological risk than single pollutants. Therefore, data on the toxicology of both single and mixed hormones is very valuable for assessment of the possibility of adverse ecological effects caused by these pollutants. Furthermore, these results suggest that environmental exposure to hormone mixtures may cause toxicity levels different to the sum of those of the single hormones and provides a basic understanding of their toxic effect on algae.


Assuntos
Clorófitas/efeitos dos fármacos , Misturas Complexas/toxicidade , Hormônios/toxicidade , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Clorófitas/crescimento & desenvolvimento , Disruptores Endócrinos/toxicidade , Microalgas/efeitos dos fármacos , Scenedesmus/efeitos dos fármacos , Scenedesmus/crescimento & desenvolvimento , Poluentes Químicos da Água/farmacologia
11.
Arch Microbiol ; 201(6): 847-854, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30888453

RESUMO

Bacteria are highly abundant in freshwater sediments and play a crucial role in biogeochemical cycling. Bacterial assemblage is known to be sensitive to heavy metal pollution. However, the shift in freshwater sediment bacterial community after a sudden exposure to heavy metal spill remains unknown. The present study explored the impact of metal (metalloid) spill on sediment bacterial community in a freshwater reservoir. Although sediment bacterial abundance was relatively insensitive to metal (metalloid) spill, bacterial richness, diversity and community structure displayed considerable temporal variations. In addition, the proportions of Proteobacteria Chloroflexi, Nitrospirae, Acidobacteria and Bacteroidetes drastically declined, while a significant enrichment of Firmicutes was observed.


Assuntos
Bactérias/efeitos dos fármacos , Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Metais Pesados/farmacologia , Poluentes Químicos da Água/farmacologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Água Doce/análise , Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Poluição Química da Água
12.
Chemosphere ; 223: 257-262, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784733

RESUMO

The involvement of transporting proteins on copper (Cu) bioaccumulation was evaluated in the killifish Poecilia vivipara chronically exposed to environmentally relevant concentrations of waterborne Cu. Fish (<24 h-old) were maintained under control condition or exposed to different waterborne Cu concentrations (5, 9 and 20 µg/L) for 28 and 345 days in saltwater. Following exposure periods, Cu accumulation and the expression of genes encoding for the high affinity Cu-transporter (ctr1) and the P-type Cu-ATPase (atp7b) were evaluated. Whole-body metal accumulation and gene expression were evaluated in fish exposed to 28 days. Similarly, in fish exposed to 345 days, liver, gills and gut were also evaluated. No fish survival was observed after exposure to 20 µg/L for 345 days. Whole-body Cu accumulation was significantly higher in fish exposed to 20 µg/L Cu for 28 days and in fish exposed to 9 µg/L for 345 days in comparison to control animals. Similarly, tissue Cu accumulation was significantly higher in fish exposed to 9 µg/L for 345 days in comparison to control animal. However, no significant accumulation was observed in fish muscle. Following exposure for 28 days, whole-body ctr1 expression was slightly induced in fish exposed to 9 µg/L. In turn, no significant change in ctr1 expression was observed following exposure to Cu for 345 days. Differently, whole-body atp7b expression was markedly up-regulated in the whole-body of fish exposed Cu for 28 days and in tissues of fish exposed to Cu for 345 days. These findings indicate the expression of atp7b is more responsive to Cu accumulation in P. vivipara than ctr1 expression and, therefore, more suitable to be used as a biomarker of exposure to this metal. Also, we argue that the expression of atp7b is sustained at elevated levels for as much time as fish are maintained in Cu contaminated water.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , ATPases Transportadoras de Cobre/metabolismo , Cobre/farmacologia , Metais/metabolismo , Poecilia/metabolismo , Animais , Fundulidae , Regulação da Expressão Gênica , Distribuição Tecidual , Poluentes Químicos da Água/farmacologia
13.
Colloids Surf B Biointerfaces ; 177: 260-266, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30763791

RESUMO

After depositing nano zinc oxide on the surface of red mud granule material by one-step hydrothermal method, a layer of cationic polyelectrolyte diallyldimethylammonium chloride is coated to obtain nano zinc oxide-cation polyelectrolyte diallyl dimethylammonium chloride (PDDA) modified red mud granule material. The modified granule material were characterized and tested. The results showed that the modified granule material has significant antibacterial activity against E. coli. And maintain a good antibacterial effect in multiple rounds of antibacterial cycle experiments. The nano zinc oxide-PDDA modified red mud granule material is convenient to prepare, low in cost, excellent in performance and easy to separate, which is beneficial to reduce microbial pollution of water bodies and risk of disinfection by-products.


Assuntos
Compostos Alílicos/farmacologia , Alumínio/farmacologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas/química , Compostos de Amônio Quaternário/farmacologia , Óxido de Zinco/farmacologia , Compostos Alílicos/química , Alumínio/química , Antibacterianos/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Compostos de Amônio Quaternário/química , Propriedades de Superfície , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacologia , Óxido de Zinco/química
14.
J Basic Microbiol ; 59(4): 385-391, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30706958

RESUMO

The effects of varying concentrations (ranging from 0 to 10 µM) of two different metals that is, iron (Fe) and copper (Cu) on indigenous bacterial populations and their hydrolytic enzyme activities within the bacterioplankton assemblages from the surface waters of the Kalamazoo River were examined under controlled microcosm conditions. The two metals were added to water samples collected from the Kalamazoo River and examined for bacterial abundance and leucine aminopeptidase activities at various time intervals over a 48 h incubation period in the dark. Results revealed no concentration effects on the bacterial populations in the presence of both Fe and Cu, although the bacterial numbers varied significantly over time in both microcosms. Conversely, leucine aminopeptidase activities based on post-hoc tests using Bonferroni correction revealed significant differences to increasing concentrations of both metals over the study period. These results further validate previous knowledge regarding the importance of various metal ions in regulating bacterial community structures and also suggest that aminopeptidase have the potential of effectively functioning using diverse trace and heavy metals as extracellular peptidase cofactors in aquatic systems.


Assuntos
Bactérias/efeitos dos fármacos , Metais Pesados/farmacologia , Fitoplâncton/efeitos dos fármacos , Rios/microbiologia , Microbiologia da Água , Poluentes Químicos da Água/farmacologia , Bactérias/enzimologia , Bactérias/crescimento & desenvolvimento , Proteínas de Bactérias/análise , Cobre/metabolismo , Cobre/farmacologia , Ferro/metabolismo , Ferro/farmacologia , Leucil Aminopeptidase/análise , Metais Pesados/metabolismo , Michigan , Fitoplâncton/enzimologia , Fitoplâncton/crescimento & desenvolvimento , Rios/química , Poluentes Químicos da Água/metabolismo
15.
Chemosphere ; 222: 333-344, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30708167

RESUMO

Oxytetracycline (OTC) is a broad-spectrum antibiotic widely used in livestock production. Like many other pharmaceuticals, OTC is not completely metabolized by the organism and thus, increasing amounts of the compound are being detected in the aquatic environment. The assessment of the environmental risk of pharmaceuticals is hindered by their very low concentrations and specific modes of action and thus relevant exposure scenarios and sensitive endpoints are needed. Thus, this work aimed to study the long-term effect of OTC exposure in zebrafish (at behavior and biochemical levels) and associated bacterial communities (fish gut and water bacterial communities). Results revealed that at behavioral level, boldness increase (manifested by increased exploratory behavior of a new environment) was observed in fish exposed to low OTC concentrations. Moreover, changes in fish swimming pattern were observed in light periods (increased stress response: hyperactivity and freezing) probably due to photo-sensibility conferred by OTC exposure. Effects at biochemical level suggest that long-term exposure to OTC interfere with cellular energy allocation mainly by reducing lipids levels and increasing energy consumption. Moreover, evidences of oxidative damage were also observed (reduced levels of TG, GST and CAT). The analysis of water and gut microbiome revealed changes in the structure and diversity of bacterial communities potentially leading to changes in communities' biological function. Some of the effects were observed at the lowest concentration tested, 0.1 µg/L which is a concentration already detected in the environment and thus clearly demonstrating the need of a serious ecotoxicological assessment of OTC effects on non-target organisms.


Assuntos
Microbioma Gastrointestinal , Oxitetraciclina/farmacologia , Peixe-Zebra/fisiologia , Animais , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Bactérias/metabolismo , Metabolismo Energético/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Oxitetraciclina/toxicidade , Natação , Poluentes Químicos da Água/farmacologia , Poluentes Químicos da Água/toxicidade
16.
Ecotoxicol Environ Saf ; 169: 894-901, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597789

RESUMO

This study aimed to evaluate the response of bacteria, in terms of microbial community structure, from constructed wetland (CW) microcosms exposed to two veterinary antibiotics, enrofloxacin (ENR) and ceftiofur (CEF), alone or in a mixture, identifying which bacterial groups were dominant in CWs substrate during livestock wastewater treatment. Wastewater, not-doped or doped with ENR and/or CEF (100 µg/L each), was treated during 18 one-week cycles. Systems showed removal percentages > 85% for the added antibiotics, showing also high removal percentages for nutrients and organic matter and confirming CWs systems were working properly. However, both time of exposure and presence of antibiotics influenced significantly CWs substrate bacterial community structure. Pyrosequencing results showed bacterial communities were dominated by phyla Proteobacteria (38-48%), Firmicutes (20-27%), Bacteroidetes (12-15%) and Actinobacteria (4-9%), and that their relative abundance was clearly affected by the presence of the antibiotics. Results suggest the applicability of CWs for the removal of veterinary antibiotics from livestock wastewaters and provide new knowledge about the bacteria within the system, which can potentially be involved in removal processes. This information could in the future be used to improve CWs removal rates of pharmaceuticals from livestock wastewaters.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Gado , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/farmacologia , Áreas Alagadas , Animais , Bactérias/crescimento & desenvolvimento , Cefalosporinas , Enrofloxacina
17.
Artigo em Inglês | MEDLINE | ID: mdl-30642109

RESUMO

This work introduces the potential synergistic toxicity of binary mixtures of pesticides and pharmaceuticals, which have been detected in substantial amounts in major river basins in South Korea. Different dose-response curve functions were employed in each experimental toxicity dataset for Aliivibrio fischeri. We tested the toxicity of 30 binary mixtures at two effect concentrations: high effect concentration [EC50] and low effect concentration (EC10) ranges. Thus, the toxicological interactions were evaluated at 60 effected concentration data points in total and based on model deviation ratios (MDRs) between predicted and observed toxicity values (e.g., three types of combined effects: synergistic (MDR > 2), additive (0.5 ≤ MDR ≤ 2), and antagonistic (MDR < 0.5)). From the 60 data points, MDRs could not be applied to 17 points, since their toxicities could not be measured. The result showed 48%-additive (n = 20), 40%-antagonistic (n = 17), and 12%-synergistic (n = 6) toxicity effects from 43 binaries (excluding the 17 combinations without MDRs). In this study, EC10 ratio mixtures at a low overall effect range showed a general tendency to have more synergistic effects than the EC50 ratio mixtures at a high effect range. We also found an inversion phenomenon, which detected three binaries of the combination of synergism at low concentrations and additive antagonism at high concentrations.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Praguicidas/toxicidade , Medicamentos sob Prescrição/toxicidade , Rios/microbiologia , Poluentes Químicos da Água/toxicidade , Relação Dose-Resposta a Droga , Interações de Medicamentos , Praguicidas/farmacologia , República da Coreia , Poluentes Químicos da Água/farmacologia
18.
J Biochem Mol Toxicol ; 33(5): e22289, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30657620

RESUMO

Triclocarban (TCC), which is used as an antimicrobial agent in personal care products, has been widely detected in aquatic ecosystems. However, the consequence of TCC exposure on embryo development is still elusive. Here, by using zebrafish embryos, we aimed to understand the developmental defects caused by TCC exposure. After exposure to 0.3, 30, and 300 µg/L TCC from 4-hour postfertilization (hpf) to 120 hpf, we observed that TCC exposure significantly increased the mortality and malformation, delayed hatching, and reduced body length. Exposure to TCC also affected the heart rate and expressions of cardiac development-related genes in zebrafish embryos. In addition, TCC exposure altered the expressions of the genes involved in hormonal pathways, indicating its endocrine disrupting effects. In sum, our data highlight the impact of TCC on embryo development and its interference with the hormone system of zebrafish.


Assuntos
Anti-Infecciosos/efeitos adversos , Carbanilidas/efeitos adversos , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/efeitos dos fármacos , Disruptores Endócrinos/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Peixe-Zebra/embriologia , Animais , Anti-Infecciosos/farmacologia , Carbanilidas/farmacologia , Embrião não Mamífero/patologia , Disruptores Endócrinos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia
19.
Sci Total Environ ; 657: 739-745, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30677939

RESUMO

This study evaluated the removal of diclofenac (DCF) in activated sludge and its long-term exposure effects on the function and structure of the microbial community. Activated sludge could remove <50% of 50 µg/L DCF. The removal decreased significantly to below 15% when DCF concentrations increased to 500 and 5000 µg/L. Quantitative assessment of the fate of DCF showed that its main removal routes were biodegradation (21%) and adsorption (7%), with other abiotic removals being insignificant (<5%). The biodegradation occurred through cometabolic mechanisms. DCF exposure in the range of 50-5000 µg/L did not disrupt the major functions of the activated sludge ecosystem (e.g. biomass yield and heterotrophic activity) over two months of DCF exposure. Consistently, 16S rRNA gene-based community analysis revealed that the overall community diversity (e.g. species richness and diversity) and structure of activated sludge underwent no significant alterations. The analysis did uncover a significant increase in several genera, Nitratireductor, Asticcacaulis, and Pseudacidovorax, which gained competitive advantages under DCF exposure. The enrichment of Nitratireductor, Asticcacaulis, and Pseudacidovorax genus might contribute to DCF biodegradation and emerge as a potential microbial niche for the removal of DCF.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Diclofenaco/metabolismo , Diclofenaco/farmacologia , Consórcios Microbianos/efeitos dos fármacos , Esgotos/microbiologia , Anti-Inflamatórios não Esteroides/farmacologia , Reatores Biológicos , Biotransformação , Consórcios Microbianos/genética , Filogenia , Eliminação de Resíduos Líquidos/instrumentação , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/farmacologia
20.
Mar Pollut Bull ; 138: 385-396, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30660288

RESUMO

To assess the impact of two plastic derived chemicals: bisphenol A (BPA) and the di-2-ethylhexyl phthalate (DEHP), on phytoplankton biomass and community structure, microcosm incubations were performed during spring and summer, with offshore and lagoon waters of a south-western Mediterranean ecosystem. Phytoplankton were exposed to an artificial mixture of BPA and DEHP and to marine water previously enriched with plastic-derivative compounds, originated from in situ water incubations of plastic debris for 30 days. After 96 h of incubation, changes were observed in phytoplankton biomass in the contaminated microcosms, with a net decrease (up to 50% of the control) in the concentration of Chlorophyll a in offshore waters. Concomitantly, plastic-derivative contamination provoked structural changes, especially for offshore waters. This suggests a relative tolerance of the lagoon communities to BPA and DEHP contamination, related to the dominance of Chaetoceros spp., which could potentially be used as a bioindicator in bioassessment studies.


Assuntos
Compostos Benzidrílicos/farmacologia , Dietilexilftalato/farmacologia , Biomarcadores Ambientais/efeitos dos fármacos , Fenóis/farmacologia , Fitoplâncton/efeitos dos fármacos , Plásticos/química , Poluentes Químicos da Água/farmacologia , Compostos Benzidrílicos/análise , Biodiversidade , Clorofila A/análise , Dietilexilftalato/análise , Ecossistema , Fenóis/análise , Fitoplâncton/crescimento & desenvolvimento , Estações do Ano , Poluentes Químicos da Água/análise , Poluição Química da Água/análise
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