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1.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3252-3264, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529901

RESUMO

The continuous discharge of pharmaceutical and personal care products (PPCPs) into aquatic environment and their potential threaten to ecological environment or human health has received more and more attention all over the world. Algae are primary producers in aquatic environment and play an important role in ecosystem balance and stabilization. In this review, the concentrations of PPCPs in natural waters from different countries and regions are introduced to demonstrate their characteristics of pollution in aquatic environment. Furthermore, we reviewed some progresses on the toxicity, bioaccumulation and ecological risk of PPCPs. We introduced the toxicity effect and mechanism of PPCPs to algae, the bioaccumulation of PPCPs in algae, as well as the ecological risks of PPCPs in surface water. The review will provide references for development of PPCPs related criteria and assessment of ecological risks in aquatic environment.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/análise , Cosméticos/análise , Cosméticos/toxicidade , Ecossistema , Poluição Ambiental , Água Doce , Humanos , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/toxicidade
2.
J Environ Sci (China) ; 85: 1-8, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471016

RESUMO

Metalaxyl is an anilide pesticide that is widely used to control plant diseases caused by Peronosporales species. In order to study the toxic effects, zebrafish embryos were exposed to metalaxyl at nominal concentrations of 5, 50 and 500 ng/L for 72 hr, and the cardiac development and functioning of larvae were observed. The results showed that metalaxyl exposure resulted in increased rates of pericardial edema, heart hemorrhage and cardiac malformation. The distance between the sinus venosus and bulbus arteriosus, stroke volume, cardiac output and heart rate were significantly increased in larvae exposed to 50 and 500 ng/L metalaxyl compared to solvent control larvae. Significant upregulation in the transcription of tbx5, gata4 and myh6 was observed in the 50 and 500 ng/L treatments, and that of nkx2.5 and myl7 was observed in the 5, 50 and 500 ng/L groups. These disturbances may be related to cardiac developmental and functional defects in the larvae. The activity of Na+/K+-ATPase and Ca2+-ATPase was significantly increased in zebrafish embryos exposed to 500 ng/L metalaxyl, and the mRNA levels of genes related to ATPase (atp2a11, atp1b2b, and atp1a3b) (in the 50 and 500 ng/L groups) and calcium channels (cacna1ab) (in the 500 ng/L group) were significantly downregulated; these changes might be associated with heart arrhythmia and functional failure.


Assuntos
Alanina/análogos & derivados , Coração/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Alanina/toxicidade , Animais , Embrião não Mamífero , Coração/efeitos dos fármacos , Peixe-Zebra/embriologia
3.
Ecotoxicol Environ Saf ; 182: 109464, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31398777

RESUMO

Chlorpyrifos (CPF) is an environmental pollutant due to its high toxicity to aquatic animals. Because CPF was detected in aquatic environments in many countries, it has been widely concerned by researchers. Although the immunotoxicity of CPF to fish had been reported, the immunotoxicity mechanism is still not clear. Recently, transcriptome analysis has become a major method to study the toxic mechanism of pollutants in environmental toxicology. However, the immunotoxicity identification of CPF on fish had not been reported by transcriptome analysis. In the present study, we examined the effects of CPF on organismal system in the spleen of common carp by transcriptome analysis. We have successfully constructed a database of transcriptome analysis of carp spleens under exposure to CPF and found 773 differentially expressed genes (DEGs) (including 498 up-regulated DEGs and 275 down-regulated DEGs) and 4 branches (containing 33 known KEGG pathways). Some genes associated with the 4 pathways (Complement and coagulation cascades, PPAR signaling pathway, Fat digestion and absorption, and Collecting duct acid secretion) contained in organismal system were validated by quantitative real-time PCR and showed significant improvement compared with the control group. Our results indicated that exposure to CPF caused a change in the signal pathways of organismal system in carp spleens. The present study provides new insights into the immunotoxicity mechanism and risk assessment of CPF, as well as references for comparative medicine.


Assuntos
Clorpirifos/toxicidade , Baço/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Atrazina/toxicidade , Carpas , Sistema Imunitário/efeitos dos fármacos , Inseticidas/toxicidade , Transdução de Sinais , Baço/fisiologia
4.
Sci Total Environ ; 685: 1294-1305, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31272786

RESUMO

Bisphenol A (BPA) is an abundant environmental contaminant and studies have shown the presence of BPA in the urine of over 90% of population tested in Canada and USA. In addition to its reported harmful effects, there is concern for its transgenerational effects. For a compound to induce transgenerational effect, an epigenetic mark should be mitotically and meiotically stable without reprogramming in primordial germ cells and post fertilization embryos. In the present study, female zebrafish were treated with an environmental dose (20 µg/L) of BPA and then crossed with untreated males. To assess epigenetic effects, transcript levels of several genes involved in female reproduction were measured in adult and in 24 hpf embryos up to F3 generation. Exposure to BPA affected adult female fertility up to F2 generation. In F0, F1 and F2 ovaries transcript levels for several genes involved in reproduction, including esr, star, lhcgr and fshr were affected. To investigate epigenetic mechanisms of gene expression modulation, we studied promoter DNA methylation. Among genes involved in gonadal differentiation, amh transcript level was reduced in 24 hpf embryos, up to the F3 generation. Variation in amh transcript level was associated with hyper-methylation of its promoter and changes in H3K4me3/H3K27me3 enrichment, coherent with gene silencing. The findings provide evidence for transgenerational effects of BPA in zebrafish and demonstrate that amh is susceptible to stable epigenetic alterations. CAPSULE: Transgenerational effects of BPA on female reproductive physiology.


Assuntos
Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Metilação de DNA , Epigênese Genética , Feminino , Histonas , Regiões Promotoras Genéticas , Peixe-Zebra
5.
Environ Monit Assess ; 191(8): 478, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31263965

RESUMO

Carwash effluents contain potentially toxic chemical and microbiological pollutants which may pose public health and ecotoxicological threats if directly discharged into surface waters. This work was aimed at determining the microbiological, physicochemical, and toxicological parameters of carwash effluents. Toxicity assays were determined using whole effluent toxicity (WET) using Danio rerio and Daphnia pulex. For microbiological analysis, sample aliquots were spread plated onto R2A Agar for the isolation of heterotrophic bacteria followed by DNA extraction from axenic cultures for sequencing analysis. The pH of effluent samples lay in the alkaline range, and ranged from pH 7 to pH 10. Sample salinity ranged from 0.2 to 0.3 g/Kg. Electrical conductivity values ranged from 274 to 554 µS/cm. Concentrations of Co, Pb, and Ni were < 1 mg/L in all samples while the concentrations of Cu ranged from 0.94 to 3.8 mg/L and Zn from 1.15 to 3 mg/L. Oil and grease concentrations ranged from 5 to 24 mg/L. The concentrations of TPH-GRO were low at < 1 mg/L in all samples. All the carwash effluents were categorised as acutely toxic, with ≥ 75% mortality recorded for both test organisms within the first 24 h of exposure to the test solutions. Heterotrophic bacteria counts ranged from 2800 to 4600 CFU/100 ml. Sequencing analysis revealed that 57% of the isolates were closely related to Aeromonas species, with 43% closely related to Pseudomonas species. We conclude that carwash effluents are veritable sources of microbiological contaminants and potentially toxic chemical pollutants of public health and ecotoxicological concern.


Assuntos
Monitoramento Ambiental , Veículos Automotores , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Bactérias , Daphnia , Ecotoxicologia , Testes de Toxicidade , Microbiologia da Água , Peixe-Zebra
6.
J Photochem Photobiol B ; 197: 111551, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31306954

RESUMO

Heavy metal pollution as one of the most serious pollution problems of marine environment, seriously threatens the safety of marine organism and human health, and will lead to potential risks for the marine ecological environment. In order to develop a rapid and sensitive toxicity detection method for marine heavy metals, in this study, marine diatom Nitzschia closterium was used as the test organism, and the effects of different concentrations of lead (Pb) on the five chlorophyll fluorescence parameters of N. closterium including the maximum photochemical quantum yield of PSII (Fv/Fm), the effective quantum yield of PSII photochemical energy conversion (ΦPSII), the effective absorption cross section of PSII photochemistry (σPSII'), the relative electron transfer rate of PSII (rP), and the PSII electron flux per unit volume (JVPII) at different exposure times were investigated based on chlorophyll fluorescence technology. By comparing with the photosynthetic activity fluorescence parameter Fv/Fm which is commonly used for toxicity analysis of pollutants using algae as test organisms, the optimal chlorophyll fluorescence parameter that could rapidly and sensitively determine Pb toxicity to N. closterium was selected. The results indicate that all the five chlorophyll fluorescence parameters of Fv/Fm, ΦPSII, σPSII', rP and JVPII showed good dose-response relationships with Pb within 8 h exposure time, and they all could be used as endpoints to rapidly determine Pb toxicity to N. closterium. Among the five chlorophyll fluorescence parameters, JVPII was the most sensitive fluorescence parameter for detecting the toxicity of Pb to N. closterium within 6 h exposure. And for JVPII, the median effective concentration (EC50) values of Pb at 2, 4 and 6 h were 0.329, 0.068 and 0.040 mmol L-1, respectively. However, when the exposure time was 8 h, ΦPSII was the most sensitive fluorescence parameter for the toxicity detection of Pb, and the EC50 value of Pb at 8 h was 0.038 mmol L-1. This study will provide an important basis for the development of a rapid and sensitive detection method for the biological toxicity of marine heavy metals, and those results will be helpful for ecological risk assessment in marine environment.


Assuntos
Clorofila/química , Chumbo/toxicidade , Microalgas/efeitos dos fármacos , Microalgas/química , Microalgas/metabolismo , Complexo de Proteína do Fotossistema II/química , Complexo de Proteína do Fotossistema II/metabolismo , Teoria Quântica , Espectrometria de Fluorescência , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
7.
Aquat Toxicol ; 213: 105229, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31255889

RESUMO

Although the global use of the 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (p,p'-DDT) has been prohibited, its persistence in the environment has caused long-lasting exposure on marine mammals. Our previous studies revealed exceedingly high residue levels of DDTs in Indo-Pacific humpback dolphins (Sousa chinensis) from the Pearl River Estuary region, China. However, the molecular mechanisms of p,p'-DDT toxicity on the dolphin are largely unknown. This study conducted the first cytotoxicity effect exploration of p,p'-DDT on the dolphin skin fibroblasts (ScSFs) to enhance the understanding of the cellular and molecular regulation impacts. ScSF cells were exposed to p,p'-DDT (28∼168 µM) for 24, 48 and 72 h. The exposure remarkably decreased viability of ScSF cells, possibly due to the synergetic effects of cell cycle arrest and apoptosis via DNA damage and mitochondria dysfunction. The DNA damage and mitochondria dysfunction were likely triggered by an increase of cellular reactive oxygen species (ROS), alteration in mitochondrial membrane potential, reduction in the cellular ATP levels, decreased expression of the genes CDK1, CDK4, cyclin B1, cyclin D1 and apoptosis regulator Bcl-2, release of cytochrome c, and activation of caspase-3, caspase-8 and caspase-9. Moreover, caspase inhibitor displayed protective activity against p,p'-DDT-induced apoptosis, indicating that caspases played a central role in p,p'-DDT-triggered apoptosis in the ScSF cells. We hypothesize apoptosis likely plays a minor role in cytocidal effects induced by p,p'-DDT exposure, but the mechanisms remain unclear. Overall, this research provides new evidence of the cytotoxic mechanisms underlying p,p'-DDT exposure on humpback dolphin skin cells, and suggests that p,p'-DDT contamination is one of key health concern issues for the protection of this marine mammal.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , DDT/toxicidade , Golfinhos/metabolismo , Exposição Ambiental , Fibroblastos/citologia , Mitocôndrias/metabolismo , Pele/citologia , Animais , Caspases/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/toxicidade
8.
Sci Total Environ ; 671: 466-473, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31331442

RESUMO

Removal of bio-accumulated pesticides in edible fish is a global problem. In this study, we tested protective capability of a phytochemical pelargonidin-loaded non-toxic, biodegradable poly-lactide-co-glycolide nano-particles (NPG) against toxicity induced by a pesticide cypermethrin (CM) in a fish model (Oreochromis mossambica) in vivo and also in L6 muscle cell line, in vitro. First we assessed potential sustainable release of nanoparticles following oral administration of NPG to fish, their ability to cross sub-cellular membranes in several tissues and efficacy to cross blood-brain-barrier. Next, protective ability of NPG, if any, against CM in fish was evaluated deploying parameters like % cell viability, DNA damage in muscle cells and modulation of anti-oxidative-enzymes like superoxide dismutase, catalase and lipid peroxidase. Modulation of reactive oxygen species generation, nuclear condensation and alteration in stress related protein signalling cascade were assessed in L6 cells. Results revealed that NPG had nano-size range (~10-12 nm) and negative zeta potential (-17 mV). Bioavailability and distribution of NPG could be followed by spectrophotometric absorbance of pelargonidin at 293 nm from 6 h onward till 24 h in all important tissues including the brain. Thus, 0.5 mg/g b.w. NPG could demonstrate protective ability in CM-intoxicated fish muscle cells in respect of % cell viability, DNA damage and stress related enzymes. Similar alterations could also be found in signalling protein cascade in L6 cells in response to treatment of 5 µg/ml NPG against CM-induced toxicity and depletion of overall ROS generation and nuclear condensation. Therefore, NPG could be used as a potential drug in management of pesticide toxicity in cultured edible fish.


Assuntos
Antocianinas/metabolismo , Antioxidantes/metabolismo , Ciclídeos/fisiologia , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Dano ao DNA , Estresse Oxidativo , Transdução de Sinais , Superóxido Dismutase/metabolismo
9.
J Environ Sci Health B ; 54(7): 580-589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31266377

RESUMO

This study aimed to compare the toxicity for fish of two active ingredients (lambda-cyhalothrin-20 g L-1, a pyrethroid, and acetamiprid-15 g L-1, a neonicotinoid) which are components of a commercial insecticide (Acer 35 EC) used in cotton crop in many West African countries. The juveniles of Oreochromis niloticus (4.01 ± 0.34 g, mean body weight) were exposed for 96 h to increasing concentrations of active ingredients (lambda-cyhalothrin and acetamiprid) or a mixture similar to Acer 35 EC (composed by 20 g of chemical compound lambda-cyhalothrin and 15 g of acetamiprid dissolved in 1 L of acetone). The experiments were carried out under controlled conditions in aquaria according to OECD Guidelines. During the experiments, the behavioral responses (loss of balance, color change, hyperactivity, etc.) that usually precede death were observed in exposed fish. Mortalities were recorded in each aquarium and the LC50-96h of each chemical was determined. The LC50-96h obtained were respectively 0.1268, 0.0029, 182.9 and 0.5685 ppm for Acer 35 EC, lambda-cyhalothrin, acetamiprid and mixture. All insecticides used in this study had profound impact on Nile tilapia behavior which may confirm the neurotoxicity of each single active compound as well as of their mixture.


Assuntos
Ciclídeos , Neonicotinoides/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Ciclídeos/fisiologia , Sinergismo Farmacológico , Inseticidas/toxicidade , Dose Letal Mediana , Mortalidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade
10.
Sci Total Environ ; 691: 278-283, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31323573

RESUMO

Local anaesthetics are among the most used drugs in clinical practice, but once they are released to the environment, the effects on the aquatic fauna remain uncertain. This study evaluates, for the first time, the impact of tetracaine, lidocaine and bupivacaine on the survival rate and physiological effects of cladocera Daphnia magna. Video-tracking and image processing allowed us to obtain changes in behaviour parameters like swimming average velocity and mean square displacement. We found that tetracaine shows the most severe effect. A high-speed microscopy system was also used to determine the response of D. magna heart to these drugs. Our results show that tetracaine presents dose-dependent area reduction during all cardiac cycle, while bupivacaine and lidocaine did not present significative effects on heart size. The tested drugs, at environmental high concentrations, altered behaviour, heart function and survival of D. magna.


Assuntos
Anestésicos Locais/toxicidade , Daphnia/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Microscopia , Natação
11.
Ecotoxicol Environ Saf ; 182: 109311, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31272021

RESUMO

Effects of sub-lethal concentrations (0 (control), 0.009, 0.014, and 0.023 ppm) of the organophosphate insecticide "malathion" to rainbow trout (Oncorhynchus mykiss) after the determination of LC50-96 h value (0.093 ppm) were evaluated. Changes in biomarkers of neurotoxicity (acetylcholinesterase (AChE) activity), genotoxicity (DNA damage), and hematological parameters (red (RBC) and white (WBC) blood cell count, hemoglobin (Hb), hematocrit (Hct), mean cell hemoglobin (MCH), mean cell volume (MCV), and mean cell hemoglobin concentration (MCHC)) were assessed for a 15-day exposure. A significant time- and dose-dependent reduction in AChE activities of gill, muscle, brain, and liver tissues was found. However, the AChE activity was less affected by malathion concentration than by exposure time. DNA damage of erythrocytes at different malathion concentrations increased by increasing the experimental time up to the fourth day. A decrease in the count of WBC, RBC, and Hct and an increase in the number of MCH and MCV were observed by increasing malathion exposure dose and time (p < 0.05). An increase in the malathion concentration and exposure time significantly resulted in a decrease in Hb and an increase in MCHC. A significant improvement in AChE activity; DNA damage; and RBC, Hb, Hct, MCV, and MCH indices was detected during a 30-day recovery period, but the WBC count changed insignificantly. The recovery pattern based on 100% water exchange with clean water could be a successful strategy to improve the biomarker responses of rainbow trout habituating in contaminated aquatic environments.


Assuntos
Acetilcolinesterase/metabolismo , Malation/toxicidade , Oncorhynchus mykiss/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Dano ao DNA , Índices de Eritrócitos , Eritrócitos/efeitos dos fármacos , Hematócrito , Hemoglobinas/análise , Dose Letal Mediana , Contagem de Leucócitos
12.
Ecotoxicol Environ Saf ; 182: 109354, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31272025

RESUMO

Selenium (Se) is a contaminant of concern in many aquatic ecosystems due to its narrow range between essentiality and toxicity in oviparous (yolk-bearing) vertebrates. The objective of the present study was to determine the effects of Se, experimentally added to in situ limnocorrals as selenite, on invertebrate communities and fathead minnow (Pimephales promelas) at environmentally realistic Se concentrations. Nine limnocorrals were deployed in a mesotrophic lake at the International Institute for Sustainable Development - Experimental Lakes Area in Ontario, Canada in May 2017. From June 1 to August 17, 2017, selenite was added to six enclosures to attain mean measured aqueous Se concentrations of 1.0 ±â€¯0.10 or 8.9 ±â€¯2.7 µg/L Se (in triplicate) and three limnocorrals were untreated controls (background mean aqueous Se = 0.12 ±â€¯0.03 µg/L). Benthic macroinvertebrates were collected throughout and at the end of the exposure period using artificial substrates to determine density, dry biomass, diversity, and taxa richness at the family level. Reproductively mature female fathead minnows (added on d 33 of the study) were collected throughout and at the end of the exposure period. After 77 d, Chironomidae and Gammaridae densities and biomass were significantly lower in the 8.9 µg/L Se treatment relative to the 1.0 µg/L Se treatment and the control. Invertebrate diversity (measured as Shannon's and Simpson's indices) significantly declined in the 1.0 µg/L and 8.9 µg/L Se treatments relative to the control (0.12 µg/L Se group). Fulton's condition factor for fathead minnow was significantly less in the 8.9 µg/L treatment compared to 0.12 and 1.0 µg/L Se experimental groups. The results of this study indicated that exposure to relatively low aqueous selenite concentrations can negatively affect invertebrate density and biomass, as well as fish condition. More research is necessary to characterize the risk of selenite exposure to aquatic invertebrates under realistic field conditions, and future risk assessments may need to consider reduced food availability as a factor that may impair the health of higher trophic level organisms in areas with elevated selenite.


Assuntos
Ecossistema , Selênio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/fisiologia , Chironomidae , Cyprinidae/fisiologia , Feminino , Invertebrados/fisiologia , Lagos , Ontário , Reprodução/efeitos dos fármacos , Ácido Selenioso/toxicidade
13.
Ecotoxicol Environ Saf ; 182: 109397, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299476

RESUMO

Cadmium (Cd) is a serious threat to plants health. Though some genes have been reported to get involved in the regulation of tolerance to Cd, the mechanisms underlying this process are not fully understood. Na+/H+ antiporter (NHX1) plays an important role in Na+/H+ trafficking. The salt and cadmium stress tolerance were found to be enhanced by NHX1 in duckweed according to our previous study, however, its function in Cd2+ flux under Cd stress has not been studied. Here we explored the Cd2+ flux in wild type (WT) and NHX1 transgenic duckweed (NHX1) under Cd stress. We found that the Cd2+ influx in NHX1 duckweed was significantly declined, followed by an increased Cd2+ efflux after 20 min treatment of Cd, which resulted a less accumulation of Cd in NHX1. Reversely, inhibition of NHX1 by amiloride treatment, enhanced Cd2+ influx in NHX1 duckweed, subsequently delayed Cd2+ efflux in both genotypes of duckweed under Cd2+ shock. H+ efflux in NHX1 duckweed was lower compare with that in WT with 20 min Cd2+ shock. NHX1 also increased the pH value with Cd2+ stress in the transgenic rhizoid. These finding suggested a new function of NHX1 in regulation of Cd2+ and H+ flow during short-term Cd2+ shock.


Assuntos
Araceae/fisiologia , Cádmio/metabolismo , Poluentes Químicos da Água/metabolismo , Araceae/metabolismo , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas/metabolismo , Sódio/metabolismo , Trocadores de Sódio-Hidrogênio , Poluentes Químicos da Água/toxicidade
14.
Chemosphere ; 233: 936-945, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340421

RESUMO

For an integrated ecological risk assessment of marine sediment contamination, the determination of target-compound concentrations by e.g. mass spectrometric methods is not sufficient to explain sediment toxicity. Due to the presence of a multitude of environmental contaminants in this complex matrix causing a mixed toxicity, the identification and assessment of main toxicants is a challenge. One approach in identifying main toxicants is the application of effect-directed analysis (EDA). In this study, an EDA approach was developed using high performance thin layer chromatography (HPTLC) coupled to bioluminescence bacteria detection with Aliivibrio fischeri for the determination of marine sediments acute toxicity. In a first attempt, the HPTLC separation was optimized with a fast, two-step gradient to separate main hydrophobic organic contaminant (HOC) classes found in marine sediments. An easy-to-use evaluation script for the resulting bioluminescence inhibition images was programed using R. The developed method was applied to sediment extracts of two different sample sets: (i) Fourteen marine sediment samples from the German Bight representing a wide range of contaminant loads and sediment properties and (ii) sediment samples from a core representing temporal trends of contamination. Results from the HPTLC-bioluminescence bacteria assay were compared to HOC concentrations determined by GC-MS/MS. A correlation of the determined inhibition Γ-values for the PAH inhibition zone to PAH concentrations showed a very good agreement (R2 = 0.91). The results of this study were used to evaluate the suitability of the EDA approach to be used as an assessment tool for marine sediments.


Assuntos
Aliivibrio fischeri/metabolismo , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Substâncias Perigosas/análise , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise , Bioensaio , Cromatografia em Camada Delgada , Cromatografia Gasosa-Espectrometria de Massas , Medição de Risco , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
15.
Chemosphere ; 233: 954-965, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340423

RESUMO

Heavy metals such as cadmium and zinc constitute major pollutants in coastal areas and frequently accumulate in salt marshes. The wetland halophyte plant species Kosteletzkya pentacarpos is a promising species for phytostabilization of contaminated areas. In order to assess the role of the antisenescing phytohormone cytokinin in heavy metal resistance in this species, seedlings were exposed for two weeks to Cd (10 µM), Zn (100 µM) or Cd + Zn (10 µM + 100 µM) in the presence or absence of 50 mM NaCl and half of the plants were sprayed every two days with the cytokinin trans-zeatine riboside (10 µM). Zinc reduced the endogenous cytokinin concentration. Exogenous cytokinin increased plant growth, stomatal conductance, net photosynthesis and total ascorbate and reduced oxidative stress estimated by malondialdehyde in Zn-treated plants maintained in the absence of NaCl. Heavy metal induced an increase in the senescing hormone ethylene which was reduced by cytokinin treatment. Plants exposed to the mixed treatment (Cd + Zn) exhibited a specific hormonal status in relation to accumulation of abscisic acid and depletion of salicylic acid. Non-protein thiols (glutathione and phytochelatins) accumulated in response to Cd and Cd + Zn. It is concluded that toxic doses of Cd and Zn have different impacts on the plant behavior and that the simultaneous presence of the two elements induces a specific physiological constraint at the plant level. Salinity helps the plant to cope with heavy metal toxicities and the plant hormone cytokinin assumes key function in Zn resistance but its efficiency is lower in the presence of NaCl.


Assuntos
Cádmio/toxicidade , Citocininas/metabolismo , Hibiscus/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Cloreto de Sódio/farmacologia , Zinco/toxicidade , Ácido Abscísico/análise , Glutationa/metabolismo , Hibiscus/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Fitoquelatinas/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Ácido Salicílico/análise , Salinidade , Plântula/fisiologia , Poluentes Químicos da Água/toxicidade , Áreas Alagadas
16.
Environ Sci Process Impacts ; 21(7): 1099-1114, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31179481

RESUMO

Endocrine active contaminants (EACs) in environmental samples can pose a range of toxicological threats to ecosystems, especially through their impacts on reproductive pathways mediated by the estrogen receptor. The physicochemical properties of known organic EACs vary greatly and typically require different sample preparation techniques to identify different classes of compounds. EAC sources are similarly diverse, including both endogenous compounds and anthropogenic chemicals found in personal care products, pharmaceuticals, and their transformation products, which are often disposed of to sewers at their end of use. Looking for EACs in sewage sludge proposes a bottom-up, or end-of-use and treatment approach to discover environmentally relevant EACs, since many EACs accumulate in sludges even after application of robust wastewater treatment processes. This study demonstrates an extraction and analytical method capable of detecting a broad spectrum of known and suspected EACs via High Resolution Liquid Chromatography Quadropole Time-of-Flight Mass Spectrometry (LC-QTOF-MS) suspect screening of fourteen California sewage sludge samples. Spike-recovery experiments were performed using twelve carefully selected surrogates to assess different extraction solvents, sample weights, extraction pH values, procedures for combining extracts with different extraction pH's, and solid phase extraction cartridges. Using LC-QTOF-MS, identifications of several other organic compounds in the samples were made, a goal unachievable with unit resolution mass spectrometry. Suspect screening of California sludge samples discovered 118 compounds including hormones, pharmaceuticals, phosphate flame retardants, recreational drugs, antimicrobials, and pesticides. Additionally, 22 of these identified compounds are predicted to interfere with estrogen receptors or other reproductive/developmental pathways based on the VEGA QSAR toxicity prediction model.


Assuntos
Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Modelos Teóricos , Esgotos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , California , Cromatografia Líquida de Alta Pressão , Valor Preditivo dos Testes , Relação Quantitativa Estrutura-Atividade , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Águas Residuárias/análise , Purificação da Água/métodos
17.
Environ Sci Pollut Res Int ; 26(23): 23571-23582, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203541

RESUMO

This study investigates the impact of humic acid (HA) on the toxicity of selected herbicides and their binary mixtures to aquatic plants. The focus was on two auxin simulators (2,4-D and dicamba) and two photosynthetic inhibitors (atrazine and isoproturon). The results suggested that the addition of HA to the standard synthetic medium does not affect Lemna minor growth nor the toxicity of atrazine, but increases the toxicity of 2,4-D and the binary mixture of atrazine and 2,4-D. The addition of HA to the standard synthetic medium reversibly decreased the growth (biomass) of Myriophyllum aquaticum and enhanced the toxicity of individually tested herbicides (isoproturon and dicamba) as well as their binary mixture. The results showed delayed toxic effects of auxin simulators, especially 2,4-D in the Lemna test. The recovery after the exposure to individual photosystem II inhibitors (atrazine and isoproturon) is fast in both plant species, regardless of the presence of HA. In the case of selected mixtures (atrazine + 2,4-D and isoproturon + dicamba), recovery of both plant species was noted, while the efficiency depended on the herbicide concentration in the mixture rather than the presence or absence of HA.


Assuntos
Herbicidas/toxicidade , Substâncias Húmicas/análise , Plantas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Araceae/efeitos dos fármacos , Atrazina/toxicidade , Dicamba , Compostos de Fenilureia , Fotossíntese/efeitos dos fármacos
18.
Environ Sci Pollut Res Int ; 26(23): 23555-23570, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203546

RESUMO

Iron (Fe) and manganese (Mn) are metals commonly found at high concentrations in underground water. These metals are essential for the good functioning of living organisms, but high concentrations lead to imbalance, potentiating the appearance of pathologies. This study aimed to evaluate the effect of exposure to naturally occurring metals in groundwater, using zebrafish (Danio rerio) as an experimental model. Thus, zebrafish were exposed to Fe (0.8 and 1.3 mg/L), Mn (0.2 and 0.4 mg/L), and groundwater collected from deep tube wells with Fe and Mn (Fe 0.8/Mn 0.2 mg/L and Fe 1.3/Mn 0.4 mg/L) for 30 days. Bioaccumulation of these metals has been demonstrated in the livers and muscles of zebrafish. Acetylcholinesterase activity changed only in zebrafish muscles in all groups. Sulfhydryl levels changed mainly in the group Mn 0.4. SOD/CAT ratio decreased in the groups Fe 0.8 and 1.3, Mn 0.4, and Fe 0.8/Mn 0.4. An increase in the frequency of micronucleus in all groups was shown as a consequence of these changes. Behavioral parameters (time and distance traveled, mean speed, turn angle, latency, and number of crossings between compartments) have also changed, mainly in the groups Fe 1.3, Mn 0.4, and Fe 1.3/Mn 0.4. Therefore, long-term exposure to Fe and Mn, even at not so high concentrations, may cause biochemical, genotoxic, and behavioral changes in zebrafish.


Assuntos
Ferro/toxicidade , Manganês/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Dano ao DNA , Água Subterrânea/química , Ferro/análise , Fígado/efeitos dos fármacos , Manganês/análise , Músculos/química , Poluentes Químicos da Água/análise
19.
Ecotoxicol Environ Saf ; 181: 1-10, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31154114

RESUMO

Pharmaceuticals are found in the aquatic compartment due to their continuous release in wastewater effluents or direct dispersal in aquaculture practices raising serious threats to human and environmental health. Erythromycin (ERY) is a macrolide antibiotic widely prescribed in human and veterinary medicine to threat a number of bacterial infections, being consequently found in the aquatic environment. The present work intends to evaluate the sub-lethal effects of ERY on juveniles of rainbow trout (Oncorhynchus mykiss) in terms of tissue damage using histochemical staining procedures. Individuals were exposed for 96 h (acute exposure: 0.001-10 mg/L) and 28 days (chronic exposure: 0.05-0.8 µg/L) to environmentally realistic concentrations of ERY. Qualitative and quantitative approaches were used to assess O. mykiss gills and liver tissue alterations after exposure to ERY. For both exposures the most common gill changes recorded were progressive (e.g. hypertrophy of mucous cells and hyperplasia of the epithelial cells). However, circulatory (e.g. aneurysms and oedemas) and regressive (e.g. epithelial lifting of lamellae and lamellar fusion) changes were also observed in the acute assay. Gill morphometric analysis revealed to be a good indicator of subtle alterations in gill architecture in agreement with the qualitative scoring system. In liver, regressive (e.g. cytoplasmic vacuolization, pyknotic nucleus and hepatocellular degeneration) and circulatory disturbances (e.g. hemorrhage and increase of sinusoidal space) were the most frequently observed alterations, but only for the acute assay. Furthermore, all histological changes observed contributed to a significant increase in the pathological index for both organs. The current data demonstrate the existence of a direct dose-effect relationship between the exposure to this specific macrolide antibiotic and the histological disorders recorded in different tissues of the exposed fish. The histopathological findings observed in this study may have been the result of several physio-metabolic dysfunctions. However, the observed tissue lesions were of minimal or moderate pathological importance, non-specific and reversible. Further investigation into the cellular mechanism of action of ERY is needed.


Assuntos
Antibacterianos/toxicidade , Eritromicina/toxicidade , Oncorhynchus mykiss/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Animais , Aquicultura , Relação Dose-Resposta a Droga , Água Doce/química , Brânquias/efeitos dos fármacos , Brânquias/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia
20.
Ecotoxicol Environ Saf ; 181: 26-33, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31154117

RESUMO

Organic ultraviolet (UV) filters are common ingredients of personal care products and occur ubiquitously in the aquatic environment; however, little is known about their distribution in and potential effects to the marine environment. This study reports the occurrence, toxicological effects and risk assessment of eleven commonly consumed UV filters in marine surface water collected from the South China Sea (SCS) coastal region. The concentrations of UV filters ranged from

Assuntos
Organismos Aquáticos/efeitos dos fármacos , Monitoramento Ambiental/métodos , Rios/química , Água do Mar/química , Protetores Solares/análise , Poluentes Químicos da Água/análise , China , Estuários , Hong Kong , Medição de Risco , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade
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