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1.
An Acad Bras Cienc ; 92(2): e20180445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32556045

RESUMO

The present work evaluated the ecological risk of glyphosate by its commercial formulation (Roundup Original®) used to control floating aquatic macrophytes. Exposure analysis and ecological effects were performed from microcosm studies. The risk characterization was performed based on the calculation of the risk quotient. The commercial formulation of glyphosate had high toxicity when it was assessed separately. On the other hand, ecotoxicological evaluation of water samples from microcosms did not present toxicity to any tested organisms, however, glyphosate application is recommended exclusively to water bodies that have the surface completely covered by macrophytes.


Assuntos
Glicina/análogos & derivados , Herbicidas/farmacologia , Poluentes Químicos da Água/farmacologia , Animais , Glicina/farmacologia , Modelos Biológicos , Medição de Risco , Testes de Toxicidade Aguda/métodos
2.
Sci Total Environ ; 735: 139496, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32480152

RESUMO

Pyriproxyfen (PPF), a broad-spectrum insecticide known to cause reproductive and endocrine disruption in invertebrates, while the data is scarce in aquatic vertebrates. The goal of this study is to investigate the impact of PPF on reproductive endocrine system of male and female zebrafish along hypothalamus-pituitary-gonadal (HPG) axis. In brain, PPF caused significant alteration in the transcripts of erα, lhß, and cyp19b genes in male and fshß, lhß, and cyp19b genes in female zebrafish. The downstream genes of steroidogenic pathway like, star, 3ßhsd, 17ßhsd, and cyp19a expression were significantly altered in gonad of both sexes. Subsequent changes in circulatory steroid hormone levels lead to imbalance in hormone homeostasis as revealed from estradiol/testosterone (E2/T) ratio. Further, the vitellogenin transcript level was enhanced in hepatic tissues and their blood plasma content was increased in male (16.21%) and declined in female (21.69%). PPF also induced histopathological changes in gonads such as, reduction of mature spermatocytes in male and vitellogenic oocytes in female zebrafish. The altered E2/T ratio and gonadal histopathology were supported by the altered transcript levels of HPG axis genes. Overall, these findings provide new insights of PPF in zebrafish reproductive system and highlights for further investigations on its potential risks in aquatic environment.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água/farmacologia , Animais , Sistema Endócrino/efeitos dos fármacos , Feminino , Gônadas/efeitos dos fármacos , Homeostase , Hipotálamo , Masculino , Piridinas , Reprodução , Vitelogeninas , Peixe-Zebra
3.
Aquat Toxicol ; 224: 105519, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32502848

RESUMO

Emamectin benzoate (EB) is a prophylactic pharmaceutical used to protect Atlantic salmon (Salmo salar) smolts migrating out of rivers and into the ocean against sea lice parasites. Randomized control trials comparing the marine survival of smolts treated with EB to a control group is used to calculate the fraction of marine mortality attributable to sea lice parasitism. However, it is assumed that there is no baseline difference in survival induced by the application of EB treatment. We used a combined laboratory and field study approach to investigate the potential impacts of EB treatment on behaviour and survival of hatchery-reared Atlantic salmon in western Norway. In aquaria experiments, EB-treated salmon smolts did not differ significantly in exploratory behaviour. Fish from treated groups responded similarly to simulated predator attack with spontaneous escape and elevated gill beat rate. Three rivers in the Osterfjord system of western Norway were selected for field experiments, Dale, Vosso, and Modalen. Dale River smolts were treated with intraperitoneal EB injections and had lower probability of detection in a wolf trap downstream of the release site than control smolts. Salmon smolts raised in the Vosso River hatchery were treated with EB delivered in their food and were detected on PIT antennas at the rivermouth of Vosso and Modalen at lower rates than control fish, but only when released at downstream sites. Calculation of risk ratios suggested that the bias in mortality caused by treatment with EB decreased the estimated survival of treated fish from an expected 18%to 46%, reducing the observable negative impact of sea lice on Atlantic salmon smolts in randomized control trials. The results suggest that estimates of the fraction of mortality attributable to sea lice may be underestimated due to lower baseline survival of treated fish caused by treatment and bring urgent attention towards a potential systematic underestimation of the impacts of sea lice on wild salmon.


Assuntos
Copépodes/efeitos dos fármacos , Ivermectina/análogos & derivados , Salmo salar/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Migração Animal/efeitos dos fármacos , Animais , Brânquias/efeitos dos fármacos , Ivermectina/farmacologia , Ivermectina/toxicidade , Modelos Teóricos , Noruega , Distribuição Aleatória , Rios/química , Salmo salar/metabolismo , Análise de Sobrevida , Poluentes Químicos da Água/farmacologia
4.
Environ Pollut ; 264: 114710, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417572

RESUMO

Bisphenol A (BPA), a monomer used for polycarbonate manufacture, has been widely reported as an endocrine-disrupting chemical (EDC). Among other alterations, BPA induces reproductive dysfunctionalities. Changes in the endocannabinoid system (ECS) have been recently shown to be associated with reproductive disorders. The ECS is a lipid-based signaling system (cannabinoid receptors, endocannabinoids and enzymatic machinery) involved in several physiological functions. The main goal of the present study was to assess the effects of two environmental concentrations of BPA (10 and 20 µg/L) on the ECS in 1-year old zebrafish gonads. In males, BPA increased the gonadosomatic index (GSI) and altered testicular levels of endocannabinoids as well as reduced the testicular area occupied by spermatogonia. In male liver, exposure to 20 µg/L BPA significantly increased vitellogenin (vtg) transcript levels. In female zebrafish, BPA altered ovarian endocannabinoid levels, elevated hepatic vtg mRNA levels as well as increased the percentage of vitellogenic oocytes in the ovaries. In conclusion, exposure to two environmentally relevant concentrations of BPA altered the ECS and consequently, gonadal function in both male and female zebrafish.


Assuntos
Disruptores Endócrinos/farmacologia , Poluentes Químicos da Água/farmacologia , Animais , Compostos Benzidrílicos/farmacologia , Endocanabinoides , Feminino , Gônadas/efeitos dos fármacos , Masculino , Fenóis , Reprodução , Vitelogeninas , Peixe-Zebra
5.
Chemosphere ; 254: 126717, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32339795

RESUMO

Pantropical spotted dolphins are apex predators and have a long lifespan, which makes them susceptible to chemical pollutants such as polybrominated diphenyl ethers (PBDEs), which are associated with immunotoxicity in wildlife. However, the effects of PBDEs and their mechanism of immunotoxicity in dolphins is largely unknown. Previously, we established fibroblast cell lines obtained from pantropical spotted dolphins (PSD-LWHT) as an in vitro model for assessing the toxicological implications of chemical pollutants in dolphins. In this study, we used the novel immortalized fibroblast cell line to explore the potential immune stimulation effect of PBDEs via prostaglandins signaling pathways to better understand the immunotoxicity pathway of PBDEs in dolphins. BDE-47, -100, and -209 exposure generally resulted in an increase in inflammatory cytokine expression, PGE2 levels, and COX-2 gene expression but BDE-209 resulted in a suppression in IL-10 production. Both protein and mRNA expression of COX-2 and PTGES increased significantly following exposure to the PBDEs. The results suggested BDE-100 and -209 increased prostaglandin E2 (PGE2) production via increased expression of COX-2 and PTGES expression. Only BDE-100 increased expression level of the prostaglandin E2 receptor EP4 while BDE-47 and BDE-209 decreased its expression. This probably explained why suppressive effect on the expression level of anti-inflammatory cytokines were only found in exposure with BDE-47 and BDE-209 rather than BDE-100. The results showed that PBDEs stimulate innate immune response by triggering PGE2-EPs-cAMP-cytokines signaling.


Assuntos
Éteres Difenil Halogenados/farmacologia , Imunidade Inata/efeitos dos fármacos , Prostaglandinas/metabolismo , Stenella/metabolismo , Animais , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Éteres Difenil Halogenados/imunologia , Bifenil Polibromatos/farmacologia , Poluentes Químicos da Água/farmacologia
6.
Mar Pollut Bull ; 154: 111078, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32319911

RESUMO

The study, for the first time, evaluated the leaching rate of zinc oxide nanoparticles (nZnO) from human skins which were applied with three commercial sunscreens containing nZnO as an active ingredient. The leaching rate of nZnO varied greatly among the sunscreens, with a range of 8-72% (mean ± SD: 45% ± 33%). We further investigated their toxicities to the marine copepod Tigriopus japonicus. We found that 96-h median lethal concentrations of the three sunscreens to T. japonicus were > 5000, 230.6, and 43.0 mg chemical L-1, respectively, equivalent to Zn2+ concentrations at >82.5, 3.2, and 1.2 mg Zn L-1, respectively. Exposure to the individual sunscreens at environmentally realistic concentrations for 96 h led to up-regulation of antioxidant genes in T. japonicus, while they triggered the release of reactive oxygen species based on the results of in vivo assays. Evidently, these nZnO-included sunscreens can cause oxidative stress and hence pose risk to marine organisms.


Assuntos
Copépodes , Nanopartículas , Poluentes Químicos da Água/farmacologia , Óxido de Zinco , Animais , Estresse Oxidativo/efeitos dos fármacos , Protetores Solares
7.
Environ Pollut ; 261: 114193, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32088440

RESUMO

Antibiotic contaminants exert stimulatory hormetic effects in cyanobacteria at low (ng L-1) concentrations, which may interfere with the control of cyanobacterial bloom in aquatic environments exhibiting combined pollution. This study investigated the influence of a mixture of four popular antibiotics (sulfamethoxazole, amoxicillin, ciprofloxacin, and tetracycline) during the application of UV-C irradiation for controlling the bloom of Microcystis aeruginosa. In the absence of antibiotics, 100-500 mJ cm-2 UV-C irradiation reduced cell density, growth rate, chlorophyll a content, Fv/Fm value and microcystin concentration in M. aeruginosa in a dose-dependent manner through the downregulation of proteins related to cell division, chlorophyll synthesis, photosynthesis and microcystin synthesis. UV-C irradiation stimulated microcystin release through the upregulation of the microcystin release regulatory protein (mcyH). The presence of 40 ng L-1 antibiotic mixture during UV-C treatment significantly reduced (p < 0.05) the treatment efficiency of 100-300 mJ cm-2 UV-C on microcystin concentration, while 80 and 160 ng L-1 antibiotic mixture significantly reduced (p < 0.05) the treatment efficiency of 100-500 mJ cm-2 UV-C on cell density and microcystin concentration. The antibiotic mixture alleviated the toxicity of UV-C on M. aeruginosa through a significant stimulation of photosynthetic activity (p < 0.05) and the upregulation of proteins involved in photosynthesis, biosynthesis, protein expression, and DNA repair. Microcystin release in UV-C-treated cyanobacterial cells was further stimulated by the antibiotic mixture through the upregulation of mcyH and four ATP-binding cassette transport proteins. The interference effects of antibiotic contaminants should be fully considered when UV-C is applied to control cyanobacterial bloom in antibiotic-polluted environments. In order to eliminate the interference effects of antibiotics, the concentration of each target antibiotic is suggested to be controlled below 5 ng L-1 before the application of UV-C irradiation.


Assuntos
Antibacterianos , Hormese , Microcystis , Raios Ultravioleta , Antibacterianos/farmacologia , Clorofila A/metabolismo , Microcistinas/metabolismo , Microcystis/efeitos dos fármacos , Microcystis/efeitos da radiação , Poluentes Químicos da Água/farmacologia
8.
Environ Pollut ; 261: 114204, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32097793

RESUMO

Antibiotic and heavy metal pollution of aquatic environments are issues of serious concern, and the macrophyte Myriophyllum aquaticum may provide a viable solution for the removal of these contaminants. However, the toxic effects of coexisting tetracyclines (TCs) and Cu(II) on this plant species are currently unclear. In the present study, we constructed wetland microcosms planted with M. aquaticum and spiked these with three TCs (tetracycline, oxytetracycline, and chlortetracycline) and Cu(II) at concentrations ranging from 100 to 10,000 µg/L to investigate how Cu(II) influences the growth and tolerance responses of plants to TCs. After 12 weeks, we found that TCs had accumulated in the plants, and that plant growth and characteristics were significantly affected by the levels of both TCs and Cu(II). While low Cu(II) levels had a synergistic effect on the accumulation of TCs, high levels were observed to reduce accumulation. However, low levels of TCs and Cu(II) had a hormesis effect on plant growth, with plant biomass and leaf chlorophyll content decreasing and the malondialdehyde content and activities of antioxidant enzymes gradually increasing with an increase in TC dosage. The coexistence of low levels of Cu(II) was, however, found to alleviate these adverse effects. Principal component analysis revealed a close relationship among plant biomass, chlorophyll content, malondialdehyde content, and antioxidant enzyme activities. Considering that the Cu/TC ratio was shown to markedly affect M. aquaticum growth, the respective proportions of these pollutants should be taken into consideration in the future design of constructed wetlands.


Assuntos
Cobre , Magnoliopsida , Tetraciclinas , Áreas Alagadas , Antibacterianos/farmacologia , Cobre/farmacologia , Magnoliopsida/efeitos dos fármacos , Magnoliopsida/crescimento & desenvolvimento , Tetraciclinas/farmacologia , Poluentes Químicos da Água/farmacologia
9.
Chemosphere ; 243: 125318, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995862

RESUMO

Increased agricultural intensification goes with the widespread use of herbicides that adversely affect aquatic biodiversity. The effects of herbicides on toxin-producing cyanobacteria have been poorly studied. The present study aimed to investigate the toxicological and physiological effects of the herbicide clethodim on Raphidiopsis raciborskii (a.k.a. Cylindrospermopsis raciborskii) ITEPA1 and Microcystis aeruginosa BCCUSP232. On day four of the experiment, the exposure to 25 mg/L clethodim resulted in the highest cell density of R. raciborskii. Similarly, exposure to the 1, 5, 20, and 50 mg/L clethodim treatments resulted in the highest cell densities of M. aeruginosa on day 4 of the experiment. Medium effect concentrations (EC50) after 96 h of exposure of both strains to clethodim were 192.98 mg/L and 168.73 mg/L for R. raciborskii and M. aeruginosa, respectively. The presence of clethodim significantly increased the total microcystin content of M. aeruginosa compared to the control cultures. At 400 mg/L, total saxitoxins content of R. raciborskii was 27% higher than that of the control cultures on day 4. In contrast, cultures exposed to 100 mg/L clethodim had the lowest saxitoxins levels per cell quota. There was an increase in the levels of intracellular hydrogen peroxide in both species during exposure to clethodim, which was followed by significant changes (p < 0.05) in the activity of antioxidant enzymes such as peroxidase and superoxide dismutase. These results revealed that the presence of low levels of clethodim in the aquatic environment might lead to the excessive proliferation of cyanobacteria and alteration of their cyanotoxins content.


Assuntos
Cicloexanonas/farmacologia , Cylindrospermopsis/efeitos dos fármacos , Cylindrospermopsis/crescimento & desenvolvimento , Microcystis/efeitos dos fármacos , Microcystis/crescimento & desenvolvimento , Antioxidantes/metabolismo , Toxinas Bacterianas/metabolismo , Cylindrospermopsis/metabolismo , Herbicidas/farmacologia , Microcistinas/metabolismo , Microcystis/metabolismo , Peroxidases/metabolismo , Saxitoxina/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/farmacologia
10.
Environ Sci Pollut Res Int ; 27(2): 1686-1696, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31755053

RESUMO

The effect of venlafaxine, a pharmaceutical commonly found in aquatic environment, was analyzed on non-target organism, Danio rerio (Hamilton, 1822). D. rerio embryos were treated by two different concentrations of venlafaxine: either concentration relevant in aquatic environment (0.3 µg/L) or concentration that was two orders of magnitude higher (30 µg/L) for the evaluation of dose-dependent effect. Time-dependent effect was rated at 24, 96, and 144 h post-fertilization (hpf). For gene expression, genes representing one of the phases of xenobiotic biotransformation (0 to III) were selected. The results of this study showed that the effect of venlafaxine on the zebrafish embryos is the most evident at hatching (96 hpf). At this time, the results showed a downregulation of gene expression in each phase of biotransformation and in both tested concentrations. In contrast, an upregulation of most of the genes was observed 144 hpf for both tested venlafaxine concentrations. The study shows that venlafaxine can affect the gene expression of biotransformation enzymes in D. rerio embryos even in the environmentally relevant concentration and thus disrupt the process of biotransformation. Moreover, the pxr regulation of genes seems to be disrupted after venlafaxine exposure in dose- and time-dependent manner.


Assuntos
Antidepressivos/farmacologia , Embrião não Mamífero/enzimologia , Regulação Enzimológica da Expressão Gênica , Cloridrato de Venlafaxina/farmacologia , Peixe-Zebra , Animais , Biotransformação , Embrião não Mamífero/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia
11.
Environ Toxicol ; 35(3): 404-413, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31738477

RESUMO

Cadmium (Cd) is one of the major contaminants in aquatic ecosystem. Stearoyl-coenzyme A desaturase 1 (Scd1) has been implicated in adaptive responses to environmental stressors. The objectives of this study are (a) to characterize scd1 mRNA from silver pomfret (Pampus argenteus); (b) to investigate the expression and activity of Scd1 in silver pomfret exposed to Cd; and (c) to investigate how Cd modifies scd1 gene transcription in silver pomfret. Results indicated that Scd1 was generally conserved across fish species and scd1 mRNA level was higher by far in the brain and liver, followed by the kidney and intestine. Exposure to Cd led to significant changes of the expression and activity of Scd1 in in the liver and intestine. The liver mRNA abundance of scd1 was significantly lower in the Cd-treated groups than in the control group. The 10 days treatment with 1 mg/L Cd significantly upregulated the intestinal scd1 mRNA level, an approximately 9-fold higher in the 1 mg/L Cd-treated group as compared with the control group. Accordingly, Scd1 activity indices (18:1n-9/18:0) in the liver were significantly decreased in the 0.5 mg/L group compared with the control group, while Scd1 activity indices in the intestine were significantly increased in the 1 mg/L group compared with the control group. Moreover, overexpression of sterol regulatory element binding transcription factor 1 (Srebp1) and peroxisome proliferator-activated receptor γ (Pparγ )in HEK 293T cells produced a 2-fold increment in the activity of the scd1 promoter. Furthermore, srebp1 had a similar expression pattern to scd1 in the liver and intestine of silver pomfret exposed to Cd. These results indicated that Cd could regulate scd1 expression, possibly through the transcriptional factor Srebp1.


Assuntos
Cádmio/farmacologia , Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Estearoil-CoA Dessaturase/genética , Transcrição Genética/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia , Animais , Peixes/metabolismo , Células HEK293 , Humanos , Fígado/metabolismo , PPAR gama/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
12.
Ecotoxicol Environ Saf ; 189: 110041, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31816496

RESUMO

Microplastic particles (MPs) from lipophilic polymers have been shown to efficiently accumulate hydrophobic organic contaminants (HOCs) in aquatic environments. MPs have, therefore, frequently been discussed as vectors for contaminants, enhancing HOC uptake by various organisms after ingestion followed by pollutant release; however, integrative models of sorption argue against this mechanism and even predict cleansing of pollutants from biological systems under particular circumstances. In order to experimentally investigate such a depuration mechanism, RTL-W1 cells were dosed with three 7-ethoxyresorufin-O-deethylase (EROD) inducers of distinct lipophilicity via the medium before adding both native and hexane-purified polyethylene MPs (20-25 µm) to the medium surface. EROD activity was significantly reduced in the presence of MP, the extent of which correlated with the inducers' lipophilicity (KOW) and thus affinity to MP. For hexane-purged MPs and TCDD (KOW = 6.8), MPs reduce the bioavailability by up to 79%; the effect was marginally weaker with benzo[k]fluoranthene (KOW = 6.11) and almost absent with ß-Naphthoflavone (KOW = 4.68). Compared to hexane-purged MPs, native particles possessed slightly less detoxification potential. These experimental results corroborate theoretically predicted mechanisms of detoxification via MPs. Yet, it is unclear if, under corresponding conditions in the environment, MPs can compete with organismal tissues for highly lipophilic compounds and, if so, to which degree they may act as a sink reducing the amount of bioavailable pollutants in situ. However, the present results suggest that in scenarios where pollutant-free MPs interact with organisms that accumulated HOCs via other routes of uptake, qualitatively the presence of such a mechanism is likely.


Assuntos
Citocromo P-450 CYP1A1/biossíntese , Indução Enzimática/efeitos dos fármacos , Microplásticos/farmacologia , Poluentes Químicos da Água/farmacologia , Animais , Linhagem Celular , Indutores das Enzimas do Citocromo P-450/farmacologia , Fluorenos/farmacologia , Interações Hidrofóbicas e Hidrofílicas , beta-Naftoflavona/farmacologia
13.
Chemosphere ; 242: 125207, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675591

RESUMO

Landfills leachate contained diverse antibiotic resistance genes (ARGs). Treated landfill leachate effluent could enter into the downstream environments, leading to the dissemination of ARGs, which might pose a health risk to public. Here, we used high-throughput qPCR to characterize the resistome and 16S rRNA-based Illumina sequencing to analyze the bacterial community in a leachate treatment plant and the river near the landfill. A total of 91 ARGs and 5 mobile genetic elements were detected. Leachate treatment process significantly changed the profiles of resistome and bacterial community structures. Similar bacterial community structure and ARG profiles were detected between effluent and downstream river, which were both dominated by multidrug and beta-lactams resistance genes and harbored higher ARG relative abundance than that in upstream river. In particular, seven ARGs were detected both in effluent and downstream river samples but not detected in upstream river, including genes encoding resistance to vancomycin (vanXD and vanSB) and carbapenem (cphA and blaGES), which implied the effects of the effluent on its receiving river. This study highlights the risk of discharge of processed landfill leachate in dissemination of antibiotic resistance determinants to the environments, and suggests an urgent need for surveillance of ARGs and development of techniques to mitigate the risk.


Assuntos
Resistência Microbiana a Medicamentos/genética , Poluentes Químicos da Água/análise , Antibacterianos/análise , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Genes Bacterianos , RNA Ribossômico 16S/genética , Rios/microbiologia , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/farmacologia
14.
Chemosphere ; 238: 124587, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31425864

RESUMO

Pharmaceuticals are emerging as environmentally problematic compounds. As they are often not appropriately removed by sewage treatment plants, pharmaceutical compounds end up in surface water environments worldwide at concentrations in the ng to µg L-1 range. There is a need to further explore single compound and mixture effects using e.g. in vivo test model systems. We have investigated, for the first time, behavioral effects in larval zebrafish (Danio rerio) exposed to a binary mixture of an antidepressant drug (citalopram) and a synthetic opioid (tramadol). Citalopram and tramadol have a similar mode of action (serotonin reuptake inhibition) and are known to produce drug-drug interactional effects resulting in serotonin syndrome (SS) in humans. Zebrafish embryo-larvae were exposed to citalopram, tramadol and 1:1 binary mixture from fertilization until 144 h post-fertilization. No effects on heart rate, spontaneous tail coiling, or death/malformations were observed in any treatment at tested concentrations. Behavior (hypoactivity in dark periods) was on the other hand affected, with lowest observed effect concentrations (LOECs) of 373 µg L-1 for citalopram, 320 µg L-1 for tramadol, and 473 µg L-1 for the 1:1 mixture. Behavioral EC50 was calculated to be 471 µg L-1 for citalopram, 411 µg L-1 for tramadol, and 713 µg L-1 for the 1:1 mixture. The results of this study conclude that tramadol and citalopram produce hypoactivity in 144 hpf zebrafish larvae. Further, a 1:1 binary mixture of the two caused the same response, albeit at a higher concentration, possibly due to SS.


Assuntos
Analgésicos Opioides/farmacologia , Citalopram/farmacologia , Inibidores de Captação de Serotonina/farmacologia , Tramadol/farmacologia , Poluentes Químicos da Água/farmacologia , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/efeitos dos fármacos , Larva/efeitos dos fármacos
15.
Environ Int ; 133(Pt B): 105199, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31675573

RESUMO

This study utilized effect-directed analysis (EDA) combined with full-scan screening analysis (FSA) to identify aryl hydrocarbon receptor (AhR)-active compounds in sediments of inland creeks flowing into Lake Sihwa, South Korea. The specific objectives were to (i) investigate the major AhR-active fractions of organic extracts of sediments by using H4IIE-luc in vitro bioassay (4 h and 72 h exposures), (ii) quantify known AhR agonists, such as polycyclic aromatic hydrocarbons (PAHs) and styrene oligomers (SOs), (iii) identify unknown AhR agonists by use of gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOFMS), and (iv) determine contributions of AhR agonists to total potencies measured by use of the bioassay. FSA was conducted on fractions F2.6 and F2.7 (aromatics with log Kow 5-7) in extracts of sediment from Siheung Creek (industrial area). Those fractions exhibited significant AhR-mediated potency as well as relatively great concentrations of PAHs and SOs. FSA detected 461 and 449 compounds in F2.6 and F2.7, respectively. Of these, five tentative candidates of AhR agonist were selected based on NIST library matching, aromatic structures and numbers of rings, and available standards. Benz[b]anthracene, 11H-benzo[a]fluorene, and 4,5-methanochrysene exhibited significant AhR-mediated potency in the H4IIE-luc bioassay, and relative potencies of these compounds were determined. Potency balance analysis demonstrated that these three newly identified AhR agonists explained 1.1% to 67% of total induced AhR-mediated potencies of samples, which were particularly great for industrial sediments. Follow-up studies on sources and ecotoxicological effects of these compounds in coastal environments would be required.


Assuntos
Sedimentos Geológicos/análise , Receptores de Hidrocarboneto Arílico/agonistas , Poluentes Químicos da Água/farmacologia , Animais , Bioensaio/métodos , Linhagem Celular Tumoral , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Lagos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Ratos , República da Coreia , Estireno/análise , Estireno/farmacologia , Poluentes Químicos da Água/análise
16.
Mar Pollut Bull ; 145: 28-35, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590789

RESUMO

Native Americans face disproportionate exposures to environmental pollution through traditional subsistence practices including shellfish harvesting. In this study, the collection of butter clams (Saxidomus giganteus) was spatially and temporally paired with deployment of sediment pore water passive samplers at 20 locations in the Puget Sound region of the Salish Sea in the Pacific Northwest, USA, within adjudicated usual and accustomed tribal fishing grounds and stations. Clams and passive samplers were analyzed for 62 individual PAHs. A linear regression model was constructed to predict PAH concentrations in the edible fraction of butter clams from the freely dissolved fraction (Cfree) in porewater. PAH concentrations can be predicted within a factor of 1.9 ±â€¯0.2 on average from the freely dissolved PAH concentration in porewater using the following equation: PAHClam=4.1±0.1×PAHporewater This model offers a simplified, cost effective, and low impact approach to assess contaminant levels in butter clams which are an important traditional food.


Assuntos
Bivalves/química , Bivalves/efeitos dos fármacos , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Frutos do Mar/análise , Poluentes Químicos da Água/farmacologia , Animais , Bivalves/crescimento & desenvolvimento , Qualidade de Produtos para o Consumidor , Monitoramento Ambiental , Humanos , Índios Norte-Americanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise
17.
Artigo em Inglês | MEDLINE | ID: mdl-31591305

RESUMO

In order to determine the role of surface water in the development and spread of antibiotic-resistant (AR) bacteria, water samples were collected quarterly from 2015 to 2016 from a mixed-use watershed in Georgia. In our previous study, 496 Escherichia coli were isolated from surface water, out of which, 34 isolates were resistant to antimicrobials. For the current study, these 34 AR E. coli were characterized using pulsed-field gel electrophoresis, AR gene detection, plasmid replicon typing, class I integron detection, and multi-locus sequence typing. Genes were identified as conferring resistance to azithromycin (mph(A)); ß-lactams (blaCMY, blaCTX, blaTEM); chloramphenicol (floR); streptomycin (strA, strB); sulfisoxazole (sul1, sul2); tetracycline (tetA, tetB, tetC); and trimethoprim/sulfamethoxazole (dhfr5, dhfr12). Five ciprofloxacin- and/or nalidixic-resistant isolates contained point mutations in gyrA and/or parC. Most of the isolates (n = 28) carried plasmids and three were positive for class I integrons. Twenty-nine sequence types (ST) were detected, including three epidemic urinary-tract-infection-associated ST131 isolates. One of the ST131 E. coli isolates exhibited an extended-spectrum ß-lactamase (ESBL) phenotype and carried blaCTX-M-15 and blaTEM-1. To our knowledge, this is the first study on the emergence of an ESBL-producing E. coli ST131 from environmental water in the USA, which poses a potential risk to human health through the recreational, agricultural, or municipal use of this natural resource. This study identified E. coli with AR mechanisms to commonly used antimicrobials and carrying mobile genetic elements, which could transfer AR genes to other bacteria in the aquatic environment.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Águas Residuárias/microbiologia , Animais , Farmacorresistência Bacteriana/efeitos dos fármacos , Monitoramento Ambiental , Escherichia coli/isolamento & purificação , Genes Bacterianos/genética , Georgia , Humanos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacologia
18.
Chemosphere ; 236: 124420, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31545208

RESUMO

The combined effects of exposure to increasing temperature and copper (Cu) concentrations were evaluated in the zooxanthellate scleractinian coral Mussismilia harttii. Endpoints analyzed included activity of enzymes involved in glycolysis (pyruvate kinase, PK; lactate dehydrogenase, LDH), Krebs cycle (citrate synthase, CS; isocitrate dehydrogenase; IDH), electron transport chain (electron transport system, ETS) and pentose phosphate pathway (glucose-6-phosphate dehydrogenase, G6PDH). Coral polyps were kept under control conditions (25.0 ±â€¯0.1 °C; 2.9 ±â€¯0.7 µg/L Cu) or exposed to combined treatments of increasing temperature (26.6 ±â€¯0.1 °C and 27.3 ±â€¯0.1 °C) and concentrations of dissolved Cu (5.4 ±â€¯0.9 and 8.6 ±â€¯0.3 µg/L) for 4 and 12 days using a mesocosm system. PK activity was not affected by stressors. LDH, CS, IDH, ETS and G6PDH activities were temporally inhibited by stressors alone. CS, ETS and G6PDH activities remained inhibited by the combination of stressors after 12 days. Furthermore, all combinations between increasing temperature and exposure Cu were synergistic after prolonged exposure. Taken together, stressors applied alone led to temporary inhibitory effects on energy metabolism enzymes of the coral M. harttii, however, prolonged exposure reveals strong deleterious effects over the metabolism of corals due to the combination of stressors. The present study is the first one to give insights into the combined effects of increasing temperature and Cu exposure in the energy metabolism enzymes of a scleractinian coral. Findings suggest that moderate Cu contamination in future increasing temperature scenarios can be worrying for aerobic and oxidative metabolism of M. harttii.


Assuntos
Antozoários/enzimologia , Cobre/farmacologia , Metabolismo Energético , Temperatura , Animais , Antozoários/efeitos dos fármacos , Ciclo do Ácido Cítrico , Glicólise , L-Lactato Desidrogenase/metabolismo , Via de Pentose Fosfato , Poluentes Químicos da Água/farmacologia
19.
Chemosphere ; 237: 124421, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31382196

RESUMO

Antibiotics in the effluents of municipal wastewater treatment plants (WWTP) may create selective pressures to induce antibiotic resistance in bacteria downstream. This study evaluates ciprofloxacin (CIP) removal by a freshwater alga, Scenedesmus dimorphus, to assess the efficacy of algae-based tertiary treatment in reducing effluent-induced CIP resistance. Results show significant CIP removal in light-exposed samples without algae and experimental algae (EA) samples: 53% and 93%, respectively, over 144 h. A residual antibiotic potency assay reveals that untreated CIP is significantly more growth-inhibiting to a model bacterium (Escherichia coli) than the algae-treated and light-exposed samples during short exposures (6 h). Adaptive laboratory evolution (ALE), again using E. coli, reveals that treated samples exhibit reduced capacity to elicit CIP resistance during sustained exposures compared to untreated CIP. Finally, observed CIP resistance in the CIP-exposed ALE lineages is corroborated via genotype characterization, which reveals the presence of resistance-associated mutations in gyrase subunit A (gyrA) that are not present in ALE lineages exposed to algae treated or light-exposed samples. As such, algae-mediated tertiary treatment could be effective in suppressing CIP resistance in bacterial communities downstream from WWTP. In addition, ALE is useful for assessing the potential of wastewater-relevant samples to elicit antibiotic resistance downstream.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacino/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Scenedesmus/metabolismo , Eliminação de Resíduos Líquidos/métodos , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Ciprofloxacino/isolamento & purificação , Ciprofloxacino/metabolismo , DNA Girase/genética , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Genótipo , Testes de Sensibilidade Microbiana , Mutação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/farmacologia
20.
J Basic Microbiol ; 59(10): 979-991, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31469183

RESUMO

This study investigates the effect of metals (cadmium, lead, mercury, and tellurium) and organic pollutants (benzene, diesel, lindane, and xylene) on a dinoflagellate-Prorocentrum sigmoides Böhm-and its associated culturable bacteria. Two bacterial cultures (Bacillus subtilis strain PD005 and B. xiamensis strain PD006) were isolated from P. sigmoides and characterized by scanning electron microscopy, 16S ribosomal RNA sequencing, biochemical analyses, and growth curve studies. This study points to a mutualistic relationship between P. sigmoides and its associated Bacillus isolates. P. sigmoides enhanced the growth of its associated Bacillus spp., through the secretion of extracellular exudates. In return, both Bacillus isolates contributed to the resistance of P. sigmoides to metals and organic pollutants. P. sigmoides and both Bacillus isolates exhibited concentration-dependent responses to metals and organic pollutants. An intriguing feature was the similar response of P. sigmoides and its associated Bacillus isolates to mercury and cadmium, indicating a co-selection of mercury and cadmium resistance. This provides support to the "dinoflagellate host-phycosphere bacteria" behaving as a single functional unit. However, the sensitivity profiles of P. sigmoides and its associated Bacillus isolates are different with respect to metals versus organic pollutants. These aspects need to be addressed in future studies to unravel the effect of metal and organic pollutants on dinoflagellates, an important component of the phytoplankton community, and to discern the influence of associated "phycosphere" bacteria on the response of dinoflagellates to pollutants.


Assuntos
Bacillus/efeitos dos fármacos , Dinoflagelados/efeitos dos fármacos , Dinoflagelados/microbiologia , Hidrocarbonetos/farmacologia , Metais/farmacologia , Poluentes Químicos da Água/farmacologia , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Bacillus/ultraestrutura , Coevolução Biológica , DNA Bacteriano/genética , Dinoflagelados/metabolismo , Resistência a Medicamentos , Microscopia Eletrônica de Varredura , RNA Ribossômico 16S/genética , Simbiose
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