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1.
Chemosphere ; 240: 124912, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574437

RESUMO

In this work, the combination of biological and electrochemical processes to mineralize oxyfluorfen has been studied. First, an acclimatized mixed-culture biological treatment was used to degrade the biodegradable fraction of the pesticide, reaching up to 90% removal. After that, the non-biodegraded fraction was oxidised by electrolysis using boron-doped diamond as the anode. The results showed that the electrochemical technique was able to completely mineralize the residual pollutants. The study of the influence of the supporting electrolyte on the electrochemical process showed that the trace mineral solution used in the biological treatment was enough to completely mineralize the oxyfluorfen, resulting in total organic carbon removal rates that were well-fitted by a first-order model with a kinetic constant of 0.91 h-1. However, the first-order degradation rate increased approximately 20% when Na2SO4 was added as supporting electrolyte, reaching a degradation rate of 1.16 h-1 with a power consumption that was approximately 70% lower.


Assuntos
Eletrólise/métodos , Éteres Difenil Halogenados/química , Éteres Difenil Halogenados/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Reatores Biológicos/microbiologia , Boro , Diamante , Eletrodos , Eletrólise/instrumentação , Cinética , Oxirredução , Praguicidas/química , Praguicidas/metabolismo , Sulfatos/química , Eliminação de Resíduos Líquidos/métodos
3.
Chemosphere ; 238: 124602, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31545211

RESUMO

Polybrominated diphenyl ethers (PBDEs) have been known to exhibit neurotoxicity in rats; however, the underlying mechanism remains unknown and there is no available intervention. In this study, we aimed to investigate the role of oxidative and nitrosative stress in the neurotoxicity in the cerebral cortex and primary neurons in rats following the BDE-153 treatment. Compared to the untreated group, BDE-153 treatment significantly induced the neurotoxic effects in rats, as manifested by the increased lactate dehydrogenase (LDH) activities and cell apoptosis rates, and the decreased neurotrophic factor contents and cholinergic enzyme activities in rats' cerebral cortices and primary neurons. When compared to the untreated group, the oxidative and nitrosative stress had occurred in the cerebral cortex or primary neurons in rats following the BDE-153 treatment, as manifested by the increments in levels of reactive oxygenspecies (ROS), malondialdehyde (MDA), nitric oxide (NO), and neuronal nitric oxide synthase (nNOS) mRNA and protein expressions, along with the decline in levels of superoxide dismutase (SOD) activity, glutathione (GSH) content, and peroxiredoxin I (Prx I) and Prx II mRNA and protein expressions. In addition, the ROS scavenger N-acetyl-l-cysteine (NAC) or NO scavenger NG-Nitro-l-arginine (L-NNA) significantly rescued the LDH leakage and cell survival, reversed the neurotrophin contents and cholinergic enzymes, mainly via regaining balance between oxidation/nitrosation and antioxidation. Overall, our findings suggested that oxidative and nitrosative stresses are involved in the neurotoxicity induced by BDE-153, and that the antioxidation is a potential targeted intervention.


Assuntos
Córtex Cerebral/patologia , Éteres Difenil Halogenados/toxicidade , Síndromes Neurotóxicas/patologia , Estresse Nitrosativo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Bifenil Polibromatos/toxicidade , Acetilcisteína/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Glutationa/metabolismo , Éteres Difenil Halogenados/metabolismo , Masculino , Malondialdeído/metabolismo , Fatores de Crescimento Neural/metabolismo , Neurônios/efeitos dos fármacos , Neurotrofina 3/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Estresse Nitrosativo/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
4.
Ecotoxicol Environ Saf ; 188: 109882, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31698175

RESUMO

Microplastics attract widespread attention, including for their potential to transport toxic chemicals in the form of plasticisers and associated hydrophobic organic chemicals, such as polybrominated diphenyl ethers (PBDEs). The aims of this study were to investigate how nylon (polyamide) microplastics may affect PBDE accumulation in snails, and the acute effects of nylon particles and PBDEs on survival, weight change and inherent microbiome diversity and community composition of the pond snail Lymnaea stagnalis. Snails were exposed for 96 h to BDEs-47, 99, 100 and 153 in the presence and absence of 1% w/w nylon microplastics in quartz sand sediment. No mortality was observed over the exposure period. Snails not exposed to microplastics lost significantly more weight compared to those exposed to microplastics. Increasing PBDE concentration in the sediment resulted in an increased PBDE body burden in the snails, however microplastics did not significantly influence total PBDE uptake. Based on individual congeners, uptake of BDE 47 by snails was significantly reduced in the presence of microplastics. The diversity and composition of the snail microbiome was not significantly altered by the presence of PBDEs nor by the microplastics, singly or combined. Significant effects on a few individual operational taxonomic units (OTUs) occurred when comparing the highest PBDE concentration with the control treatment, but in the absence of microplastics only. Overall within these acute experiments, only subtle effects on weight loss and slight microbiome alterations occurred. These results therefore highlight that L. stagnalis are resilient to acute exposures to microplastics and PBDEs, and that microplastics are unlikely to influence HOC accumulation or the microbiome of this species over short timescales.


Assuntos
Éteres Difenil Halogenados/metabolismo , Lymnaea/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Animais , Carga Corporal (Radioterapia) , Exposição Ambiental/análise , Retardadores de Chama/análise , Retardadores de Chama/metabolismo , Retardadores de Chama/toxicidade , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/toxicidade , Lymnaea/metabolismo , Lymnaea/microbiologia , Nylons/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Sheng Wu Gong Cheng Xue Bao ; 35(11): 2121-2132, 2019 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-31814359

RESUMO

Polybrominated diphenyl ethers (PBDEs) are widely used brominated flame-retardants in a variety of commercial products especially in the electronics and household industries. However, they are bioaccumulative, biotoxic and persistent, making them a globally distributed organic chemical toxin nowadays. Thus, it is extremely important to degrade PBDEs. This paper illustrates the research progress of metabolic pathways of PBDEs under both aerobic and anaerobic conditions, and also combines with in situ degradation studies to infer the degradation potential of archaea. The characteristics and comprehensive factors of various degradation pathways are analyzed. In addition, future researches on biodegradation mechanism of PBDEs, the design and application of PBDEs degradation system are discussed.


Assuntos
Archaea , Biodegradação Ambiental , Éteres Difenil Halogenados , Archaea/metabolismo , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/metabolismo , Pesquisa/tendências
6.
Environ Pollut ; 255(Pt 2): 113151, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31550656

RESUMO

Severe contamination of decabrominated diphenyl ether (BDE-209, an emerging persistent organic pollutant) in coastal marine sediments has posed a serious threat to the marine ecosystems. Anaerobic microbial degradation can affect the toxicity and environmental fate of BDE-209 in anoxic marine sediments. However, little is known about the anaerobic microbial degradation of BDE-209 in anoxic marine/coastal sediments. In this study, the anaerobic degradation of BDE-209 in microcosms containing coastal marine sediments from a contaminated bay located in Southern China was investigated. It was observed that over 70% of the BDE-209 (5 µmol) added to the anaerobic sediment microcosms disappeared after 90-day of incubation. Thirty-five debrominated products (tetra- to nonaBDEs) were identified by GC-MS. Remarkably, a majority of these products (i.e. 20 products, including BDE-52, -92, -101, -102, -103, -133, -144, -146, -150, -161, -171, -172, -175, -177, -178, -180, -182, -188, -193, -199) have not been previously reported in the literature on the anaerobic microbial degradation of BDE-209 in sediments. There was no preferential debromination among ortho-, meta-, and para-bromines on BDE-209 and higher-brominated diphenyl ethers were the predominant debromination products. High-throughput sequencing revealed that the relative abundances of 9 microbial genera in the sediment microcosms increased as the anaerobic degradation of BDE-209 progressed, indicating their involvements in the degradation process. Taken together, our findings provided new insights into the anaerobic microbial degradation of BDE-209 in anoxic marine sediments.


Assuntos
Poluentes Ambientais/metabolismo , Sedimentos Geológicos/microbiologia , Éteres Difenil Halogenados/metabolismo , Anaerobiose , Biodegradação Ambiental , Bromo , China , Ecossistema , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/química , Éteres Difenil Halogenados/análise
7.
Sci Total Environ ; 692: 1106-1115, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539942

RESUMO

The aim of this study was to investigate levels of polybrominated diphenyl ethers (PBDEs) in breast milk samples from healthy primiparous mothers who had lived in Kampala capital city (urban area) and Nakaseke district (a rural area) for the last five years. Fifty samples were collected between March and June 2018 and were extracted by dispersive solid-phase extraction (SPE). Clean-up was performed on an SPE column and analysis was done using gas chromatography-mass spectrometry. Total (∑) PBDEs (BDE 28, 47, 49, 66, 77, 99, 100,138,153, 154, 183 and 209) ranged from 0.59 to 8.11 ng/g lipid weight (lw). The levels of PBDEs in samples from Kampala capital city were significantly higher than those from Nakaseke (p < 0.01, Mann-Whitney U test). The most dominant congeners were BDE-209 and -47 (contributed 37.1% and 20.2%, respectively to ∑PBDEs), suggesting recent exposure of mothers to deca-and penta-BDE formulations. Fish and egg consumption, plastics/e-waste recycling and paint fumes were associated with higher levels of BDE-47, -153 and -99, respectively, implying that diet and occupation were possible sources of the pollutants. Estimated dietary intakes (ng kg-1 body weight day-1) for BDE-47, -99 and -153 were below the US EPA reference doses for neurodevelopmental toxicity, suggesting minimal health risks to nursing infants who feed on the milk. Generally, the risk quotients for BDE-47, -99 and -153 were <1 in majority (96%) samples, indicating that the breast milk of mothers in Uganda was fit for human consumption.


Assuntos
Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/metabolismo , Exposição Materna , Leite Humano/metabolismo , Resíduo Eletrônico , Feminino , Humanos , Lactente , Bifenil Polibromatos , Uganda
8.
Sci Total Environ ; 691: 789-798, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326802

RESUMO

Many organohalogen compounds (OHCs) are persistent organic pollutants (POPs) found in appreciable concentrations in marine predators. While production of some POPs has declined or ceased in recent decades, their capacity for global transport and bioaccumulation results in observations of unchanging or increasing concentrations in marine systems. Sea otters (Enhydra lutris) have been advocated as an environmental sentinel for contaminants due to their longevity, site fidelity and prey species that often overlap with human consumption. Using archived (1992-2010) samples of livers from Northern sea otters (n = 50) from Alaska we examine concentrations of chlordanes (CHLs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDTs), and polybrominated diphenyl ethers (PBDEs) and associated metabolites. We found some evidence for declining ΣPCBs over the two decades, however for most animals concentrations were low compared to toxicological thresholds. Six animals had relatively high concentrations of ΣPCBs (mean = 262,000 ng/g lipid weight), ΣDDTs (mean = 8,800 ng/g lw), and ΣPBDEs (mean = 4,600 ng/g lw), with four of these six animals experiencing hepatic parasitism or hepatitis. In order to assess whether differences in POP concentrations are associated with feeding ecology, we examined stable isotopes of C and N in archived muscle and whisker samples. In general, there were no significant relationships between ΣPOP concentrations and stable isotope ratios. There were small differences in stable isotope profiles in animals with high POP concentrations, although it was unclear if these differences were due to feeding ecology or disease processes. This study highlights the importance of considering feeding ecology and necropsy (health and disease status) data while conducting contaminant surveys, and confirms some previous reports of trends in OHCs in Alaska marine mammals.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/metabolismo , Lontras/metabolismo , Poluentes Químicos da Água/metabolismo , Alaska , Animais , DDT/metabolismo , Ecologia , Éteres Difenil Halogenados/metabolismo , Bifenilos Policlorados/metabolismo
9.
Sci Total Environ ; 689: 278-286, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276995

RESUMO

The levels of eight polybrominated diphenyl ether (PBDE) congeners, and six novel brominated flame retardants (NBFRs) were determined in human milk collected from Beijing, China in 2014. The tested 111 samples were collected from 37 mothers, and each donor provided one milk sample per month for 3 months after childbirth. Levels of ∑PBDEs (total tri- to deca-BDEs) were in the range of 0.288 to 22.2 ng g-1 lw (lipid weight). BDE-209, with a median level of 2.2 ng g-1 lw, was the predominant congener. Decabromodiphenyl ethane (DBDPE), as an NBFR and a substitute for deca-BDE, was found to be the most abundant BFR in all tested human milk (median:5.96 ng g-1 lw). This result might suggest that the predominantly consumed BFRs in China have changed from PBDEs to PBDE substitutes. Additionally, a comparison to our previous studies conducted in 2005 and 2011 revealed that levels of tri- to hepta-BDEs showed significant reduction from 2005 to 2014, whereas levels of BDE-209 showed no significant variation from 2011 to 2014. Temporal trends of BFR levels over the three months of lactation were also investigated, and no significant changes were found in concentration with time over the three months lactation. For nursing infants up to 6 months old, the median lower bound of daily BFR intakes via human milk ingestion ranged from zero for 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and 1,2-bis(2,4,6-tribromophenoxy)-ethane (BTBPE) to 18.7 ng kg-1 bodyweight day-1 for DBDPE. Although the daily dietary BFR intake for nursing infants was found to be much higher than that for adults, the risk assessment evaluated by the margin of exposure (MOE) approach revealed that dietary BFR intake for nursing infants was unlikely to pose significant health risks.


Assuntos
Exposição Ambiental , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/metabolismo , Leite Humano/química , Adulto , Pequim , Aleitamento Materno , Feminino , Halogenação , Humanos , Lactente , Recém-Nascido , Medição de Risco , Estações do Ano
10.
Chemosphere ; 232: 63-69, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31152904

RESUMO

PBDEs occur in a range of commonly consumed foods but there is very little current information on occurrence in dietary supplements such as cod liver oil or cod livers used as food. This study retrospectively investigated a number of these products, sourced from the Baltic Sea and North Atlantic, historically dating from 1972 to 2017. For the sum of 17 measured PBDEs (ΣPBDE), the concentrations ranged from 9.9 to 415 ng g-1 for the oils and from 10.5 to 13 ng g-1 for canned liver products. Concentrations in the oils were highest during the period from 1993 to 2001. For all samples, BDE-47 was the dominant congener with a maximum detected concentration of 308 ng g-1 in a Baltic cod liver oil from 1993. Human exposure to PBDEs from recommended doses were estimated for adults, teenagers and children. Depending on the age group, BDE-47 intakes ranged from 1.3 to 211.5 ng kg-1 bm day-1 (Baltic Sea), 2.9-12.7 ng kg-1 bm day-1 (Atlantic, Norway) and 1.1-4.8 ng kg-1 bm day-1 (Atlantic, Iceland). Intakes for the other dominant congeners, BDE-49, BDE-99 and BDE-100, were relatively low. The intake estimates of ΣPBDE were highest for Baltic cod liver oils ranging from 2.2 to 284.8 ng kg-1 bm day-1 for adults, 2.8-178 ng kg-1 bm day-1 for teenagers and 2.0-127.8 ng kg-1 bm day-1 for a child. Estimated weekly intake of ΣPBDE from canned cod liver was highest for adults, ranging from 17.6 to 25.1 ng kg-1 bm.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Gadus morhua/metabolismo , Éteres Difenil Halogenados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Países Bálticos , Monitoramento Ambiental , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/análise , Humanos , Islândia , Fígado/química , Noruega , Bifenil Polibromatos , Estudos Retrospectivos
11.
Chemosphere ; 233: 140-148, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31170584

RESUMO

Polybrominated diphenyl ethers (PBDEs) are ubiquitous and toxic contaminants found in high concentrations in watercourses, and are not well removed by conventional wastewater treatment facilities. This study aimed to evaluate the removal and transformation of BDE-47, one of the environmentally predominant PBDE congener, by a green alga (Chlorella vulgaris) and a cyanobacterium (Microcystis flos-aquae) under different light conditions. Living and autoclaved cultures were exposed to BDE-47 at a concentration of 10 µg L-1 for 7 days. Both species removed >90% of BDE-47 very shortly after spiking. Light intensity affected the transformation of BDE-47 in living cultures of both species, since 5 to 11 times more debromination products were measured at a light intensity of 100 µmol photons m-2 s-1 than at 20 µmol photons m-2 s-1. Living cultures of M. flos-aquae transformed BDE-47 at a rate of 0.22 day-1 while no transformation was observed in the respective autoclaved cultures. On the contrary, both living and autoclaved cultures of C. vulgaris had similar BDE-47 transformation rates of 0.05-0.06 day-1. Debromination of BDE-47 was a predominant transformation pathway in cultures of C. vulgaris, with two times higher BDE-28 concentrations measured than in M. flos-aquae, while hydroxylation was more dominant with the cyanobacterium. Most BDE-47 and its debromination product BDE-28 were found on the cell surface of both species. These results reveal that different transformation mechanisms were involved in C. vulgaris and M. flos-aquae cultures and confirm the importance of species selection for the removal of PBDEs from contaminated environments.


Assuntos
Chlorella vulgaris/metabolismo , Éteres Difenil Halogenados/metabolismo , Microcystis/metabolismo , Biodegradação Ambiental , Chlorella vulgaris/citologia , Éteres Difenil Halogenados/química , Hidroxilação , Luz , Microcystis/citologia , Bifenil Polibromatos/metabolismo , Técnicas de Cultura de Tecidos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias
12.
J Environ Sci (China) ; 83: 133-143, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31221376

RESUMO

The degradation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) by Pycnoporus sanguineus was investigated in order to explore the impact of the heavy metal Cu2+ on BDE-47 decomposition and the subsequent formation of metabolites, as well as to further elucidate the degradation mechanism of BDE-47. An increase in degradation rate from 18.63% to 49.76% in the first four days and its stabilization at (51.26 ±â€¯0.08)% in the following days of BDE-47 incubation were observed. The presence of Cu2+ at 1 and 2 mg/L was found to promote the degradation rate to 56.41% and 60.79%, respectively, whereas higher level of Cu2+ (≥5 mg/L) inhibited the removal of BDE-47. The similar concentration effects of Cu2+ was also found on contents of fungal protein and amounts of metabolites. Both intracellular and extracellular enzymes played certain roles in BDE-47 transportation with the best degradation rate at 27.90% and 27.67% on the fourth and third day, individually. During the degradation of BDE-47, four types of hydroxylated polybrominated diphenyl ethers (OH-PBDEs), i.e., 6'-OH-BDE-47, 5'-OH-BDE-47, 4'-OH-BDE-17, 2'-OH-BDE-28, and two bromophenols, i.e., 2,4-DBP and 4-BP were detected and considered as degradation products. These metabolites were further removed by P. sanguineus at rates of 22.42%, 23.01%, 27.04%, 27.96%, 64.21%, and 40.62%, respectively.


Assuntos
Biodegradação Ambiental , Cobre/metabolismo , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/metabolismo , Pycnoporus/metabolismo
13.
mBio ; 10(3)2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088928

RESUMO

Marine sponges are recognized as valuable sources of bioactive metabolites and renowned as petri dishes of the sea, providing specialized niches for many symbiotic microorganisms. Sponges of the family Dysideidae are well documented to be chemically talented, often containing high levels of polyhalogenated compounds, terpenoids, peptides, and other classes of bioactive small molecules. This group of tropical sponges hosts a high abundance of an uncultured filamentous cyanobacterium, Hormoscilla spongeliae Here, we report the comparative genomic analyses of two phylogenetically distinct Hormoscilla populations, which reveal shared deficiencies in essential pathways, hinting at possible reasons for their uncultivable status, as well as differing biosynthetic machinery for the production of specialized metabolites. One symbiont population contains clustered genes for expanded polybrominated diphenylether (PBDE) biosynthesis, while the other instead harbors a unique gene cluster for the biosynthesis of the dysinosin nonribosomal peptides. The hybrid sequencing and assembly approach utilized here allows, for the first time, a comprehensive look into the genomes of these elusive sponge symbionts.IMPORTANCE Natural products provide the inspiration for most clinical drugs. With the rise in antibiotic resistance, it is imperative to discover new sources of chemical diversity. Bacteria living in symbiosis with marine invertebrates have emerged as an untapped source of natural chemistry. While symbiotic bacteria are often recalcitrant to growth in the lab, advances in metagenomic sequencing and assembly now make it possible to access their genetic blueprint. A cell enrichment procedure, combined with a hybrid sequencing and assembly approach, enabled detailed genomic analysis of uncultivated cyanobacterial symbiont populations in two chemically rich tropical marine sponges. These population genomes reveal a wealth of secondary metabolism potential as well as possible reasons for historical difficulties in their cultivation.


Assuntos
Cianobactérias/genética , Metagenômica , Poríferos/microbiologia , Simbiose/genética , Animais , Produtos Biológicos/metabolismo , Cianobactérias/metabolismo , Genômica , Éteres Difenil Halogenados/metabolismo , Indóis/metabolismo , Família Multigênica , Filogenia , Pirróis/metabolismo , Clima Tropical
14.
Environ Sci Pollut Res Int ; 26(19): 19871-19878, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31090007

RESUMO

Dissolved organic matter (DOM) extracted from wheat straw (SDOM) and cow manure (MDOM) were used to investigate their effects on the solubilization, uptake, and translocation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47). Partition coefficients (KDOC) of BDE 47 between water and the two types of DOM were measured by the solubility enhancement method. The uptake and translocation of BDE 47 by wheat plants were explored by hydroponic exposure experiments. In the range of 0 to 100 mg/L of DOM, the solubility of BDE 47 increased with increasing concentrations of DOM. The log [KDOC] values of BDE 47 in SDOM and MDOM solutions were 5.77 and 5.31, respectively. The log [KDOC] values of BDE 47 in SDOM solutions were higher than those in MDOM solutions, which might be ascribed to the higher content of aliphatic carbon and lower molecular weight of SDOM. The addition of DOM (50 mg/L) significantly increased the accumulation of BDE 47 in the shoots of wheat plants. Wheat straw DOM had greater effect than MDOM in enhancing the accumulation of BDE 47. This study demonstrated the potential risk of BDE 47 to plants resulting from DOM-facilitated transport or the changes in metabolic properties.


Assuntos
Éteres Difenil Halogenados/metabolismo , Substâncias Húmicas/análise , Resíduos Industriais/análise , Poluentes do Solo/metabolismo , Agricultura , Animais , Bovinos , Éteres Difenil Halogenados/química , Esterco/análise , Silagem/análise , Poluentes do Solo/química , Solubilidade , Triticum/química
15.
Sci Total Environ ; 659: 1186-1198, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096332

RESUMO

This study investigated the occurrence of 135 contaminants of emerging concern (CECs) - pharmaceuticals, pesticides, a set of endocrine disrupting compounds (EDCs) (parabens, bisphenols, hormones, triazoles, organophosphorus flame retardants and triclosan), UV-filters, perfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs) - in 59 fish samples, collected in 2010 in 4 Spanish Rivers (Guadalquivir, Júcar, Ebro and Llobregat). Of the 135 CECs, 76 including 8 pharmaceuticals, 25 pesticides, 10 EDCs, 5 UV-filters, 15 PFASs and 13 HFRs were detected. Pharmaceuticals were the less frequently found and at lower concentrations. Pesticides, EDCs, UV-filters, PFASs and HFRs were detected more frequently (>50% of the samples). The maximum concentrations were 15 ng/g dry weight (dw) for pharmaceuticals (diclofenac), 840 ng/g dw for pesticides (chlorpyrifos), 224 ng/g dw for EDCs (bisphenol A), 242 ng/g dw for UV-filters (EHMC), 1738 ng/g dw for PFASs (PFHxA) and 64 ng/g dw for HFRs (Dec 602). The contaminants detected in fish are commonly detected also in sediments. In light of current knowledge, the risk assessment revealed that there was no risk for humans related to the exposure to CECs via freshwater fish consumption. However, results provide detailed information on the mixtures of CECs accumulated that would be very useful to identify their effects on aquatic biota.


Assuntos
Monitoramento Ambiental , Peixes/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Disruptores Endócrinos/análise , Disruptores Endócrinos/metabolismo , Retardadores de Chama/análise , Retardadores de Chama/metabolismo , Água Doce/química , Sedimentos Geológicos/química , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/metabolismo , Praguicidas/análise , Praguicidas/metabolismo , Rios/química , Espanha , Poluentes Químicos da Água/análise
16.
Sci Total Environ ; 668: 958-965, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31018474

RESUMO

GY1, a novel microbial consortium with efficient ability to degrade decabromodiphenyl ether (BDE-209) has been isolated and the sequencing analysis has been conducted. The results revealed that Hyphomicrobium, Pseudomonas, Aminobacter, Sphingopyxis, Chryseobacterium, Bacillus, Pseudaminobacter, Stenotrophomonas, Sphingobacterium and Microbacterium were the dominant genera, and the function genes involved in BDE-209 conversion were predicted by PICRUSt. When BDE-209 concentration increased from 0.5 to 10mg/L, its degradation efficiency declined from 57.2% to 22.3%. Various kinds of debrominated metabolites were detected during the biodegradation process, including BDE-208, BDE-207, BDE-206, BDE-205, BDE-190, BDE-181, BDE-155, BDE-154, BDE-99, BDE-47, BDE-17 and BDE-7. Also, the proportion of necrotic cells was observed during GY1 mediated degradation of BDE-209 to reveal the changes of cells viability under BDE-209 stress. Subsequent analysis showed that the reaction of BDE-209 with GY1 was a detoxification process and bioaugmentation with GY1 effectively enhanced BDE-209 degradation in actual water and water-sediment system.


Assuntos
Bactérias/metabolismo , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/metabolismo , Consórcios Microbianos , Bactérias/classificação , Biodegradação Ambiental
17.
Environ Sci Pollut Res Int ; 26(12): 12171-12180, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30830665

RESUMO

In this study, pine needles were used as biomonitors to investigate the levels, spatial distributions, and possible sources of polybrominated diphenyl ethers (PBDEs) and four emerging halogenated flame retardants (HFRs) in the atmosphere of Shanghai, China. The four emerging HFRs were hexabromocyclododecane (HBCD), decabromodiphenylethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), and dechlorane plus (DP), with the first 3 HFRs being non-polybrominated diphenyl ether brominated flame retardants (non-PBDE BFRs). The total concentrations ranged from 3.71 to 4020 ng g-1 dry weight (dw) for 52 PBDE congeners (Σ52BDEs), < MDL (method detection limit) to 15.2 ng g-1 dw for three non-PBDE BFRs (Σ3non-PBDE BFRs), and 0.815 to 1090 pg g-1 dw for two DP isomers (ΣDP), respectively. High levels of PBDEs, three non-PBDE BFRs, and DP were found in pine needles from suburbs and Pudong, which was a consequence of industrial activities. The fraction of anti-DP isomer (fanti) in pine needles ranged from 0.515 to 0.939 with a mean value of 0.721, and most of the fanti values were consistent with those of technical DP formulations. Principal component analysis-multiple linear regression (PCA-MLR) model identified four sources of PBDEs in pine needles with the quantified contributions: degradation of technical PBDE formulations (49.5%), technical deca-BDE (6.9%), technical penta-BDE (25.1%), and technical octa-BDE (18.5%). These findings are expected to help understand the pollution level, fate, and possible sources of HFRs in the atmosphere of Shanghai and provide a basis for air pollution control and management in Shanghai.


Assuntos
Poluentes Atmosféricos/metabolismo , Monitoramento Ambiental , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/metabolismo , Poluentes Atmosféricos/análise , Atmosfera/química , China , Poluição Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Halogenação , Hidrocarbonetos Bromados , Hidrocarbonetos Clorados , Pinus/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Compostos Policíclicos
18.
Bioresour Technol ; 283: 28-35, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30897390

RESUMO

In this study, a 200-day deca-brominated diphenyl ether (deca-BDE) degradation activity experiment was carried out, using consumer-use curtain material as the substrate. During the degradation process, polybrominated diphenyl ether (PBDE) products with fewer bromine atoms were gradually generated by the debromination of deca-BDE. The influences of temperature, initial substrate dosing mass, and pH were also investigated. Interestingly, thermophilic conditions proved more beneficial for deca-BDE degradation than mesophilic conditions. The results also demonstrate that the debromination rate increased with the initial deca-BDE dosing mass, and that pH 7 was the most suitable for the reaction.


Assuntos
Compostos de Bromo/metabolismo , Éteres Difenil Halogenados/metabolismo , Anaerobiose , Bifenil Polibromatos/metabolismo , Temperatura Ambiente
19.
Chemosphere ; 225: 217-225, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877916

RESUMO

2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is a predominant polybromodiphenyl ether congener in the environment. Its absorption, excretion, and metabolism in animals have been investigated; however, the distribution of BDE-47 and its metabolites in excreta and blood at steady-state conditions has been unclear. In the present study, we addressed the issue by determining the amounts of BDE-47, eight monohydroxylated metabolites (OH-BDEs), and 2,4-dibromophenol (2,4-DBP) in serum, urine, and feces of gpt delta transgenic mice orally administered BDE-47 at 1.5, 10, and 30 mg/kg/d for 6 weeks during the 24 h period (for urine and feces) or at 24 h (for blood) post-last dosing. The distribution profiles in the three matrices showed that BDE-47, OH-BDEs, and 2,4-DBP were mostly distributed in urine (59-70%), feces (95-96%), and urine (51-80%), respectively. In each matrix, BDE-47 was the predominant compound under all doses, which accounted for 84-96% in serum, 68-98% in urine, and 37-92% in feces. However, exclusive of BDE-47, OH-BDEs were the predominant class of metabolites in serum (72-86%) and feces (67-87%), whereas 2,4-DBP was the major metabolite in urine (98-99%). Among monohydroxylated metabolites, the dominant compounds were 4-hydroxy-2,2',3,4'-tetrabromodiphenyl ether (4-OH-BDE-42) and 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether (4'-OH-BDE-49) in feces (27-33% and 25-43%, respectively), and 3-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (3-OH-BDE-47) in serum (26-43%). Thus, BDE-47 and 2,4-DBP were mostly present in urine, and OH-BDEs were primarily found in feces. Blood was not an important carrier for either BDE-47 or its metabolites. The data provide information for distribution and elimination of BDE-47 and its metabolites in mice at steady-state conditions.


Assuntos
Fezes/química , Éteres Difenil Halogenados/metabolismo , Animais , Éteres Difenil Halogenados/sangue , Éteres Difenil Halogenados/urina , Camundongos , Microssomos Hepáticos/metabolismo , Fenóis/sangue , Fenóis/metabolismo , Fenóis/urina
20.
Environ Sci Pollut Res Int ; 26(11): 10562-10575, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30762185

RESUMO

The aim of this study was to assess the temporal change of atmospheric deposition patterns of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in Switzerland between 1995 and 2014 by a passive biomonitoring with lichens. Lichen tissues sampled at 16 representative sites in the same season of 1995 and 2014 were analyzed for a total of 94 individual and 27 sum parameters of POPs and PAHs by means of gas chromatography-mass spectrometry (GC/MS). The comparative analyses showed a decrease of 40 to 80% (medians) for most of the POPs and PAHs concentration in lichens at all site categories. Reduction in tissue concentration of the polychlorinated dibenzo-p-dioxins/furans (PCDD/PCDFs), such as the highly toxic 2,3,7,8-TetraCDD and the TEQ according to WHO (2005) were 66% and 73%, respectively. For the dioxin- and non-dioxin-like PCBs, a decrease of 67% and 58% was found. The average decrease of 30 organochlorine pesticides and insecticides (OCPs) was 65%, with a 94% decrease for lindane. For the 27 PAHs and for benzo(a)pyrene, an average decrease of 58% and 59% was found. Polybrominated diphenyl ethers (PBDE) showed reduced concentrations in lichens at rural and agglomeration sites, but an increase of contamination was observed at industrial and road traffic sites. The direct comparison of changes of POPs and PAHs concentrations in lichens and of emissions between 1995 and 2014 revealed consistent results. The results of this study highlight for the first time in biota the positive effect of emission regulation of POPs in Switzerland.


Assuntos
Poluentes Ambientais/análise , Éteres Difenil Halogenados/análise , Hidrocarbonetos Clorados/análise , Líquens/química , Praguicidas/análise , Dibenzodioxinas Policloradas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados/metabolismo , Hidrocarbonetos Clorados/metabolismo , Líquens/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Suíça
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