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1.
Ecotoxicol Environ Saf ; 245: 114090, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162350

RESUMO

Air pollution includes polycyclic aromatic hydrocarbons (PAHs), which have been correlated to endocrine disruptor pathways during early pregnancy. PAHs have been found in the placenta and cord blood, which may affect the hormones involved in placental development. We studied the effects of some airborne PAHs on beta human chorionic gonadotropin (ß-hCG) and progesterone production by using a syncytial BeWo cell line as a placental model. PAH congeners were spiked in silicon rubber membrane (SRMs) and were then introduced into the cell medium by the passive dosing method to reach a freely dissolved concentration for BeWo cell exposure. Ultrahigh-performance liquid chromatography coupled with a diode array detector was used to analyze the PAHs, and electrochemiluminescence was used to test the hormone levels. Our results showed that passive dosing can deliver low levels of PAH congeners in the cell medium, which allowed us to calculate the individual release constants at equilibrium and to estimate their effects. Benzo[a]pyrene was released quickly from the SRMs to the cell medium, which can be attributed to its lipophilic properties. The PAHs were shown to decrease the ß-hCG level in the short term and progesterone level in the long term, so they may serve as a pathway for endocrine disorder in trophoblastic cells. This approximation may explain observations of impaired endometrium receptivity and placental dysfunction, which enhance adverse pregnancy outcomes such as embryonic mortality and intrauterine growth restriction.


Assuntos
Disruptores Endócrinos , Hidrocarbonetos Policíclicos Aromáticos , Benzo(a)pireno/análise , Linhagem Celular , Gonadotropina Coriônica/análise , Gonadotropina Coriônica/metabolismo , Gonadotropina Coriônica/farmacologia , Disruptores Endócrinos/análise , Feminino , Humanos , Técnicas In Vitro , Placenta/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Gravidez , Progesterona/metabolismo , Borracha , Silício/farmacologia
2.
J Environ Manage ; 323: 116148, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36088761

RESUMO

Biochar (BP) obtained from palm fiber wastes was combined with H2O2, peroxymonosulfate (PMS), or persulfate (PDS) to treat valsartan, acetaminophen, and cephalexin in water. BP activated PMS and PDS but no H2O2. Computational calculations indicated that interactions of PMS and PDS with BP are more favored than those with HP. The highest synergistic effect was obtained for the removal of valsartan by BP + PMS. This carbocatalytic process was optimized, evaluating the effects of pH, BP dose, and peroxymonosulfate concentration, and minimizing the oxidant quantity to decrease costs and environmental impacts of the process. SO4•-, HO•, 1O2, and O2•- were the agents involved in the degradation of the pharmaceuticals. The reusability of BP was tested, showing that the carbocatalytic process removed ∼80% of target pollutants after 120 min of treatment even at the fourth reuse cycle. Also, the process decreased the phytotoxicity of the treated sample. Simulated hospital wastewater was treated and its components induced competing effects, but the system achieved the target pharmaceuticals removal in this matrix. Additionally, the analysis of environmental impact using a life cycle assessment unraveled that the carbocatalytic process had a carbon footprint of 2.87 Kg CO2-Eq, with the biochar preparation (which involves the use of ZnCl2 and electric energy consumption) as the main hotspot in the process.


Assuntos
Oxidantes , Poluentes Químicos da Água , Acetaminofen , Dióxido de Carbono/análise , Cefalexina/análise , Carvão Vegetal , Peróxidos , Preparações Farmacêuticas , Valsartana/análise , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise
3.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199337

RESUMO

This study aimed to understand the adsorption process of cephalexin (CPX) from aqueous solution by a biochar produced from the fiber residue of palm oil. Scanning electron microscopy, Fourier transform infrared spectroscopy, Boehm titration, and the point of zero charge were used to characterize the morphology and surface functional groups of the adsorbent. Batch tests were carried out to evaluate the effects of the solution pH, temperature, and antibiotic structure. The adsorption behavior followed the Langmuir model and pseudo-second-order model with a maximum CPX adsorption capacity of 57.47 mg g-1. Tests on the thermodynamic behavior suggested that chemisorption occurs with an activation energy of 91.6 kJ mol-1 through a spontaneous endothermic process. Electrostatic interactions and hydrogen bonding represent the most likely adsorption mechanisms, although π-π interactions also appear to contribute. Finally, the CPX removal efficiency of the adsorbent was evaluated for synthetic matrices of municipal wastewater and urine. Promising results were obtained, indicating that this adsorbent can potentially be applied to purifying wastewater that contains trace antibiotics.


Assuntos
Cefalexina/análise , Óleo de Palmeira/química , Poluentes Químicos da Água/análise , Adsorção , Carvão Vegetal/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Purificação da Água
4.
Environ Sci Technol ; 48(4): 2218-25, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24455968

RESUMO

The photodegradation of chlorothalonil, a polychlorinated aromatic fungicide widely used in agriculture, was investigated under ultraviolet-visible irradiation in the presence and absence of different humic substances that significantly enhance the chlorothalonil phototransformation. On the basis of a kinetic model, an analytical study, the effect of scavengers, the chlorothalonil phosphorescence measurement, and varying irradiation conditions, it was possible to demonstrate that this accelerating effect is due to their capacity to reduce the chlorothalonil triplet state via H-donor reaction and to energy transfer from the triplet humic to ground state chlorothalonil. Energy transfer occurs at wavelengths below 450 nm and accounts for up to 30% of the reaction in deoxygenated medium upon irradiation with polychromatic light (300-450 nm). This process is more important with Elliott humic and fulvic acids and with humic acids extracted from natural carbonaceous material than with Nordic NOM and Pahokee peat humic acids. The obtained results are of high relevance to understanding the processes involved in chlorothalonil phototransformation and the photoreactivity of humic substances. Chlorothalonil is one of the rare molecules shown to react by energy transfer from excited humic substances.


Assuntos
Transferência de Energia , Substâncias Húmicas/análise , Luz , Nitrilas/efeitos da radiação , Fotólise/efeitos da radiação , Ar , Fungicidas Industriais/química , Fungicidas Industriais/efeitos da radiação , Cinética , Nitrilas/química , Oxigênio/química , Solo , Soluções , Raios Ultravioleta
5.
Environ Sci Pollut Res Int ; 30(59): 123616-123632, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37991611

RESUMO

Pristine pyrogenic carbonaceous material (BRH) obtained from rice husk and modified with FeCl3 (BRH-FeCl3) were prepared and explored as carbocatalysts for the activation of peroxymonosulfate (PMS) to degrade a model pharmaceutical (acetaminophen, ACE) in water. The BRH-FeCl3/PMS system removed the pharmaceutical faster than the BRH/PMS. This is explained because in BRH-FeCl3, compared to BRH, the modification (iron played a role as a structuring agent mainly) increased the average pore diameter and the presence of functional groups such as -COO-, -Si-O-, or oxygen vacancies, which allowed to remove the pollutant through an adsorption process and significant carbocatalytic degradation. BRH-FeCl3 was reusable during four cycles and had a higher efficiency for activating PMS than another inorganic peroxide (peroxydisulfate, PDS). The effects of BRH-FeCl3 and PMS concentrations were evaluated and optimized through an experimental design, maximizing the ACE degradation. In the optimized system, a non-radical pathway (i.e., the action of singlet oxygen, from the interaction of PMS with defects and/or -COO-/-Si-O- moieties on the BRH-FeCl3) was found. The BRH-FeCl3/PMS system generated only one primary degradation product that was more susceptible to biodegradation and less active against living organisms than ACE. Also, the BRH-FeCl3/PMS system induced partial removals of chemical oxygen demand and dissolved organic carbon. Furthermore, the carbocatalytic system eliminated ACE in a wide pH range and in simulated urine, having a low-moderate electric energy consumption, indicating the feasibility of the carbocatalytic process to treat water polluted with pharmaceuticals.


Assuntos
Oryza , Água , Peróxidos/química , Preparações Farmacêuticas
6.
Ultrason Sonochem ; 82: 105861, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34902815

RESUMO

Substances such as pharmaceuticals, pesticides, dyes, synthetic and natural hormones, plasticizers, and industrial chemicals enter the environment daily. Many of them are a matter of growing concern worldwide. The use of ultrasound to eliminate these compounds arises as an interesting alternative for treating mineral water, seawater, and urine. Thereby, this work presents a systematic and critical review of the literature on the elimination of organic contaminants in these particular matrices, using ultrasound-based processes. The degradation efficiency of the sonochemical systems, the influence of the nature of the pollutant (volatile, hydrophobic, or hydrophilic character), matrix effects (enhancement or detrimental ability compared to pure water), and the role of the contaminant concentration were considered. The combinations of ultrasound with other degradation processes, to overcome the intrinsic limitations of the sonochemical process, were considered. Also, energy consumptions and energy costs associated with pollutants degradation in the target matrices were estimated. Moreover, the gaps that should be developed in future works, on the sonodegradation of organic contaminants in mineral water, seawater, and urine, were discussed.


Assuntos
Poluentes Químicos da Água/análise , Poluentes Ambientais , Águas Minerais , Água do Mar , Poluentes Químicos da Água/farmacocinética
7.
Bioresour Technol ; 326: 124753, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33545628

RESUMO

Acetaminophen (ACE), cephalexin (CPX), and valsartan (VAL) are recognized water pollutants, which can be removed by adsorption. Herein, the removal of these pharmaceuticals using a biochar (BP), prepared from oil palm fiber, was tested. It was studied the structural effects of the pharmaceuticals and biochar on the adsorption process supported by experimental and computational results, plus characterizations of the material. The biochar has 76.05 m2 g-1 of surficial area, and carboxylic groups (1.343 mmol g-1) predominantly. The maximum adsorption uptakes were 7.3, 7.9, and 23.85 mg g-1 for ACE, CPX, and VAL, respectively; following pseudo-second-order kinetics. The best pollutants removal was obtained at acidic pH (3.0). Computational analyses indicated that oxygenated groups of BP (able to generate H-bond interactions) influenced the adsorption of pharmaceuticals. It can be remarked that BP is a low-cost adsorbent synthesized easily from wastes, with high feasibility to remove pharmaceutical structures from water.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Água , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 792: 148360, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34146813

RESUMO

Carbapenem-resistant Klebsiella pneumoniae is a critical priority pathogen according to the World Health Organization's classification. Effluents of municipal wastewater treatment plants (EWWTP) may be a route for K. pneumoniae dissemination. Herein, the inactivation of this microorganism in simulated EWWTP by the photo-electro-oxidation (PEO) and photo-electro-Fenton (PEF) processes was evaluated. Firstly, the disinfecting ability and action pathways of these processes were established. PEO achieved faster K. pneumoniae inactivation (6 log units in 75 min of treatment) than the PEF process (6 log units in 105 min of treatment). PEO completely inactivated K. pneumoniae due to the simultaneous action of UVA light, electrogenerated H2O2, and anodic oxidation pathways. The slower inactivation of K. pneumoniae when using PEF was related to interfering screen effects of iron oxides on light penetration and the diffusion of the bacteria to the anode. However, both PEO and PEF avoided the recovery and regrowth of treated bacteria (with no detectable increase in the bacteria concentration after 24 h of incubation). In addition to the bacteria evolution, the effect of treatment processes on the resistance gene was examined. Despite inactivation of K. pneumoniae by PEF was slower than by PEO, the former process induced a stronger degrading action on the gene, conferring the resistance to carbapenems (PEF had a Ct value of 24.92 cycles after 105 min of treatment, while PEO presented a Ct of 19.97 cycles after 75 min). The results of this research indicate that electrochemical processes such as PEO and PEF are highly effective at dealing with resistant K. pneumoniae in the EWWTP matrix.


Assuntos
Klebsiella pneumoniae , Poluentes Químicos da Água , Carbapenêmicos , Peróxido de Hidrogênio , Ferro , Klebsiella pneumoniae/genética , Oxirredução , Águas Residuárias , Água , Poluentes Químicos da Água/análise
9.
Ultrason Sonochem ; 80: 105814, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34763213

RESUMO

This work considered the sonochemical degradation (using a bath-type reactor, at 375 kHz and 106.3 W L-1, 250 mL of sample) of three representative halogenated pharmaceuticals (cloxacillin, diclofenac, and losartan) in urine matrices. The action route of the process was initially established. Then, the selectivity of the sonochemical system, to degrade the target pharmaceuticals in simulated fresh urine was compared with electrochemical oxidation (using a BDD anode, at 1.88 mA cm-2), and UVC/H2O2 (at 60 W of light and 500 mol L-1 of H2O2). Also, the treatment of cloxacillin in an actual urine sample by ultrasound and UVC/H2O2 was evaluated. More than 90% of the target compounds concentration, in the simulated matrix, was removed after 60 min of sonication. However, the sono-treatment of cloxacillin in the real sample was less efficient than in the synthetic urine. The ultrasonic process achieved 43% of degradation after 90 min of treatment in the actual matrix. In the sonochemical system, hydroxyl radicals in the interfacial zone were the main degrading agents. Meanwhile, in the electrochemical process, electrogenerated HOCl was responsible for the elimination of pharmaceuticals. In turn, in UVC/H2O2 both direct photolysis and hydroxyl radicals degraded the target pollutants. Interestingly, the degradation by ultrasound of the pharmaceuticals in synthetic fresh urine was very close to the observed in distilled water. Indeed, the sonodegradation had a higher selectivity than the other two processes. Despite the sono-treatment of cloxacillin was affected by the actual matrix components, this contrasts with the UVC/H2O2, which was completely inhibited in the real urine. The sonochemical process led to 100% of antimicrobial activity (AA) elimination after 75 min sonication in the synthetic urine, and âˆ¼ 20% of AA was diminished after 90 min of treatment in the real matrix. The AA decreasing was linked to the transformations of the penicillin nucleus on cloxacillin, the region most prone to electrophilic attacks by radicals according to a density theory functional analysis. Finally, predictions of biological activity confirmed that the sono-treatment decreased the activity associated with cloxacillin, diclofenac, and losartan, highlighting the positive environmental impact of degradation of chlorinated pharmaceuticals in urine.


Assuntos
Poluentes Químicos da Água , Cloxacilina , Diclofenaco , Peróxido de Hidrogênio , Radical Hidroxila , Losartan , Preparações Farmacêuticas , Ultrassom , Poluentes Químicos da Água/análise
10.
Environ Sci Pollut Res Int ; 27(34): 42390-42404, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32870429

RESUMO

Air pollution is an important cause of non-communicable diseases globally with particulate matter (PM) as one of the main air pollutants. PM is composed of microscopic particles that contain a mixture of chemicals and biological elements that can be harmful to human health. The aerodynamic diameter of PM facilitates their deposition when inhaled. For instance, coarse PM having a diameter of < 10 µm is deposited mainly in the large conducting airways, but PM of < 2.5 µm can cross the alveolar-capillary barrier, traveling to other organs within the body. Epidemiological studies have shown the association between PM exposure and risk of disease, namely those of the respiratory system such as lung cancer, asthma, and chronic obstructive pulmonary disease (COPD). However, cardiovascular and neurological diseases have also been reported, including hypertension, atherosclerosis, acute myocardial infarction, stroke, loss of cognitive function, anxiety, and Parkinson's and Alzheimer's diseases. Inflammation is a common hallmark in the pathogenesis of many of these diseases associated with exposure to a variety of air pollutants, including PM. This review focuses on the main effects of PM on human health, with an emphasis on the role of inflammation.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Doença Pulmonar Obstrutiva Crônica , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Humanos , Material Particulado/análise
11.
J Hazard Mater ; 371: 273-279, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30856437

RESUMO

The presence of levonorgestrel (LNG) in water bodies via direct discharge and human excretion has been reported worldwide, but its effects on the reproduction of aquatic species and humans are still unknown. Owing to its recalcitrant properties, LNG is not completely removed during wastewater treatment plants, and many species may be exposed to low traces of this compound from discharged effluents. Thus, in this study, a photocatalytic process for removing LNG along with screening of endocrine disruptor effects for risk assessment was applied. Although the removal rate of LNG by ultraviolet C (UV-C) radiation was >90%, reproductive toxicity testing using the BeWo cell line exposed to LNG and its degraded fraction showed the reduced production of basal human chorionic gonadotropin hormone (ß-hCG) by more than 73%, from 8.90 mIU mL-1 to <2.39 mIU mL-1, with both LNG and the degraded fraction. ß-hCG hormone has been implicated in the viability of trophoblastic cells during the first trimester of pregnancy; therefore, degraded fractions and waterborne LNG may affect reproduction in some aquatic species and humans with low level of exposure.


Assuntos
Disruptores Endócrinos/toxicidade , Levanogestrel/toxicidade , Poluentes Químicos da Água/toxicidade , Catálise , Linhagem Celular , Disruptores Endócrinos/química , Feminino , Humanos , Levanogestrel/química , Processos Fotoquímicos , Gravidez , Poluentes Químicos da Água/química
12.
Water Res ; 94: 1-9, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26921708

RESUMO

This study focuses on the photo-transformation, in presence of humic substances (HSs), of ciprofloxacin (CIP), a commonly-used fluoroquinolone antibiotic whose presence in aquatic ecosystems is a health hazard for humans and other living organisms. HSs from the International Humic Substances Society (Elliott humic acid and fulvic acid, Pahokee peat humic acid and Nordic lake) and a humic acid extracted from modified coal (HACM) were tested for their ability to photodegrade CIP. Based on kinetic and analytical studies, it was possible to establish an accelerating effect on the rate of CIP decomposition caused by the humic substances. This effect was associated with the photosensitized capacity of the HSs to facilitate energy transfer from an excited humic state to the ground state of ciprofloxacin. Except for Nordic lake, which experienced a lower positive effect, no significant differences in the CIP transformation were found among the different humic acids examined. The photochemistry of CIP can be modified by parameters such as pH, CIP or oxygen concentration. The irradiation of this antibiotic in the presence of HACM showed that antimicrobial activity was negligible after 14 h for E. coli and 24 h for S. aureus. In contrast, the antimicrobial activity was only slightly decreased after 24 h of irradiation by direct photolysis. Although mineralization of CIP irradiation in the presence of a HACM solution was not achieved, biodegradability was achieved after 12 h of irradiation, indicating that microorganisms within the environment can easily degrade CIP photochemical by-products.


Assuntos
Antibacterianos/química , Ciprofloxacina/química , Substâncias Húmicas , Fotólise , Poluentes Químicos da Água/química , Benzopiranos/química , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Cinética , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos
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