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1.
Int J Mol Sci ; 24(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37511556

RESUMO

The removal of nitrogen from coal tar pitch (CTP) through the hydrodenitrogenation (HDN) of CTP and its molecular behavior were evaluated in the presence of NiMo/γ-alumina and CoMo/γ-alumina catalysts. Fourier transform ion cyclotron resonance mass spectrometry with atmospheric pressure photoionization was used to analyze the complicated chemical classes and species of CTP and the treated products at the molecular level. Nitrogen species were qualitatively analyzed before and after hydrotreatment. A single-stage hydrotreatment with an HDN catalyst resulted in a high sulfur removal performance (85.6-94.7%) but a low nitrogen removal performance (26.8-29.2%). Based on relative abundance analyses of nitrogen and binary nitrogen species, CcHh-NnSs was the most challenging species to remove during HDN treatment. Furthermore, prior hydrodesulfurization was combined with HDN treatment, and the dual hydrotreatments yielded a significantly improved nitrogen removal performance (46.4-48.7%).


Assuntos
Alcatrão , Nitrogênio/química , Óxido de Alumínio , Desnitrificação , Espectrometria de Massas/métodos
2.
Chemosphere ; 335: 139095, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37268225

RESUMO

Research investigating the desorptive behaviour of PAHs from contaminated soils often overlooked the effects of source materials, especially coal tar and coal tar pitch and materials alike. In this study, a refined experimental approach was adopted to establish a simple-to-complex continuum of systems that allow the investigation of desorption kinetics of benzo(a)pyrene (BaP) and 3 other carcinogenic PAHs (cPAHs) over an incubation period of 48 d. By comparing the modelled desorption parameters, elucidation of the effects of PAH source materials on their desorptive behaviour was achieved. Desorption of cPAHs from coal tar and pitch was enhanced when they were added to soils, with rapidly desorbing fraction (Frap) of BaP increased from 0.68% for pitch to 1.10% and 2.66% for pitch treated soils, and from 2.57% for coal tar to 6.24% for coal tar treated soil G and 8.76% for coal tar treated sand (1 d). At 1 d, desorption of target cPAHs from solvent and source material spiked soils generally followed the order of solvent > coal tar > pitch. Increases in Frap of cPAHs were observed in coal tar-treated soils after 48 d soil incubation (0.33%-1.16% for soil M, p ≥ 0.05, 6.24%-9.21% for soil G, p < 0.05) and was attributed to the continuous migration of coal tar as a non-aqueous phase liquid (NAPL) into soil pore structures. Slow desorption was dominated by source materials, whereas the extents and rates of rapid desorption (Frap and krap) were more controlled by the quantity of soil organic matter (SOM), rather than quality of SOM (as in solvent-spiked soils). The results of this study challenged the role of PAH source materials as 'sinks' and led to the proposed roles of coal tar and pitch and source materials alike as 'reservoirs' with a risk-driven perspective.


Assuntos
Alcatrão , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Carcinógenos , Alcatrão/química , Cinética , Hidrocarbonetos Policíclicos Aromáticos/análise , Solventes , Solo/química , Poluentes do Solo/análise
3.
J Environ Manage ; 337: 117679, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36934504

RESUMO

Coal tar residue (CTR) is acknowledged as hazardous industrial waste with high contents of carbon and toxic polycyclic aromatic hydrocarbons (PAHs). Microwave-assisted extraction for separating tar and residue in CTR was investigated to reduce the content of PAHs. The key operating factors such as solvent type, solvent addition amount, radiation temperature, and radiation time in the extraction process were evaluated. Results showed that extreme extraction performance in the solvent with cyclic structure was attained, and an enhancement in extraction efficiency was achieved in elevated solvent addition amount, radiation temperature, or radiation time in a certain range. The optimized conditions were determined as benzene was chosen as extractant, solvent-solid ratio of 5:1 mL/g, radiation temperature of 75 °C, and radiation time of 10 min. Relative extraction efficiency of CTR and reduction efficiency of 16 priority control PAHs were 28.70% and 92.82%, respectively. According to the characterizations of extracted residue (MCTR) and tar (MCT) under optimum experimental conditions, it is possible to convert them into value-added products (carbon materials, solid fuels, or chemicals). Solid-oil separation via microwave-assisted extraction is a safe and high-valued utilization approach for CTR.


Assuntos
Alcatrão , Hidrocarbonetos Policíclicos Aromáticos , Alcatrão/química , Hidrocarbonetos Policíclicos Aromáticos/química , Micro-Ondas , Solventes , Carbono
4.
Int J Dermatol ; 62(3): 290-301, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35398899

RESUMO

Tars are one of the most effective, unknown, and oldest therapies for psoriasis. They include coal tar (CT) and biomass-derived products. These treatments, particularly the CT, have proven to be cost-effective with long remission times compared to other systemic or topical treatments. However, they have hardly evolved in recent years, as they are not well-embraced by clinicians or patients because of concerns regarding cosmesis and safety. This review summarizes current knowledge about the chemical characterization, mechanism of action, toxicity, and clinical studies supporting the use of tars for psoriasis over the last decade. Trends within these above aspects are reviewed, and avenues of research are identified. CT is rich in polycyclic aromatic hydrocarbons, whereas biomass-derived tars are rich in phenols. While the activation of the aryl hydrocarbon receptor is involved in the antipsoriatic effect of CT, the mechanism of action of biomass-derived products remains to be elucidated. No conclusive evidence exists about the risk of cancer in psoriasis patients under CT treatment. Large, randomized, double-blind, controlled clinical trials are necessary to promote the inclusion of tars as part of modern therapies for psoriasis.


Assuntos
Alcatrão , Cosméticos , Fármacos Dermatológicos , Psoríase , Humanos , Alcatrões/efeitos adversos , Psoríase/tratamento farmacológico , Alcatrão/efeitos adversos , Alcatrão/química , Fármacos Dermatológicos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Environ Technol ; 44(10): 1379-1391, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34739358

RESUMO

The processing of coal tar pitch (CTP) to produce clean fuel gas and carbon black (CB) is studied in a plasma reactor equipped with a direct-current plasma torch. The composition of the gas produced and energy costs were estimated theoretically for the CTP pyrolysis and gasification processes by two oxidants, namely oxygen and water vapor. We have found that the main gaseous compounds obtained in the pyrolysis and gasification processes are hydrogen (H2), carbon monoxide (CO), and very often carbon dioxide (CO2). For the pyrolysis case, the mean value of the synthesis gas concentration reaches a major value of 98 vol.% (H2 - 81 vol.%, CO - 17. vol.%). However, only 23% of the initial CTP is transformed into gas phase at 1100 K and its content increases up to 37.4% at a temperature of 3000 K. For oxygen gasification, the syngas quantity is little less compared to the pyrolysis case and attains 96.6 vol.% (H2 - 26.5 vol.%, CO - 70.1 vol.%) for T > 1100 K. An intermediate syngas content for the water steam gasification is 97.8 vol.% (with H2 - 55.8 vol.% and CO - 42.0 vol.%). The CB produced was composed of well-defined spherical particles of 30-nm size. Furthermore, it is composed of carbon (98.2%), and followed by oxygen (1.8%) with a surface area of 97 m2 g-1. The thermal plasma system shows high efficiency in conversion of CTP into high-value-added products.


Assuntos
Alcatrão , Gases em Plasma , Fuligem , Gases , Vapor , Hidrogênio , Oxigênio , Biomassa
6.
Cutis ; 110(2 Suppl): 8-14, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36219602

RESUMO

Topical medications have high utility in the treatment of psoriasis because of their localized effect and ability to be used as both monotherapy and adjunctive therapy. The American Academy of Dermatology (AAD) and the National Psoriasis Foundation (NPF) published guidelines in 2020 regarding the management of psoriasis with topical therapies. These guidelines are a framework that assist clinicians treating psoriasis patients with topical agents including steroids, calcineurin inhibitors (CNIs), vitamin D analogues, retinoids (tazarotene), emollients, keratolytics (salicylic acid), anthracenes (anthralin), and keratoplastics (coal tar). This review presents these evidence-based recommendations in a form that dermatologists can readily apply to their clinical practice. The selection of an appropriate topical therapy, effective combination therapies, duration of use, and adverse events are addressed.


Assuntos
Alcatrão , Fármacos Dermatológicos , Psoríase , Administração Tópica , Antralina/uso terapêutico , Inibidores de Calcineurina/uso terapêutico , Alcatrão/efeitos adversos , Emolientes/uso terapêutico , Humanos , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Retinoides/uso terapêutico , Ácido Salicílico , Esteroides/uso terapêutico , Vitamina D
7.
Environ Int ; 169: 107548, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36179645

RESUMO

Phenanthrene (PHE), mainly released from coal tar and petroleum distillation, is an important kind of prevalent polycyclic aromatic hydrocarbons (PAHs) contamination in China (up to 2.38 ± 0.02 mg/kg in soil and 8668 ng/L in surface water) and other countries in the world. Metal-organic frameworks (MOFs) show promising application prospects in the decontamination field, however, suffering from the intrinsic fragility and fine powder forms. Therefore, macroscopic MOFs architecture-sandwich-like Fe-ZIF-8/blue TiO2 nanotube arrays (BTNAs)/Ti substrate (FBTT) anode with strong interfacial bonding (Fe-O-Ti and Fe-2-MIM-Ti coordination) was constructed using innovative in situ growth, condensation-crystallization-deposition, and pyrolysis methods, aiming at exploring the feasibility of MOFs-based anode/peroxymonosulfate (PMS) mediated PHE elimination, revealing the in-depth mechanisms, simultaneously overcoming the intrinsic drawbacks of MOFs. The FBTT-4 (doping content of 30 %) efficiently degraded PHE by 90.01 % and 74.5 % within 10 min at 350 µg/L and 3 mg/L, respectively, mediated by the ·OH compared to the SO4·-, 1O2, and O2·-. Post-optimized range of anodic potential enabled (i) anodic oxidation, (ii) activation of water and PMS molecules to produce active species, (iii) capture of electrons in reactants to reduce Fe3+/Ti4+ to Fe2+/Ti3+, maintaining the proportion of Fe/Ti with low valence and thus stable PMS activation capacity, and (iv) regulation of the Fe/Ti d-band center to modulate the anode adsorption capacity. The further increment in anodic potential could promote "dark photocatalysis" with a Z-scheme-like mechanism. Thus, it is proposed that the development of macroscopic MOFs-based anode, especially those with small band gaps, represents vast potentials in electrocatalytic contamination elimination. Simultaneously, the MOFs-based anode is expected to fully exploit their catalytic capacities and solve their intrinsic defects as well.


Assuntos
Alcatrão , Estruturas Metalorgânicas , Petróleo , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Catálise , Eletrodos , Peróxidos , Pós , Solo , Titânio , Água
8.
Environ Sci Technol ; 56(18): 12988-12998, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36041117

RESUMO

Pavement sealants are of environmental concern because of their complex petroleum-based chemistry and potential toxicity. Specifically, coal tar-derived sealants contain high concentrations of toxic/carcinogenic polycyclic aromatic hydrocarbons (PAHs) that, when weathered, can be transferred into the surrounding environment. Previous studies have demonstrated the effects of coal tar sealants on PAH concentration in nearby waterways and their harmful effects in aquatic ecosystems. Here, we investigate and compare the molecular composition of two different pavement sealants, petroleum asphalt- and coal tar-derived, and their photoproducts, by positive-ion (+) atmospheric pressure photoionization (APPI) and negative-ion (-) electrospray ionization (ESI) coupled with ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry to address species (high-boiling and/or high oxygen content) that lie outside the analytical window of other techniques due to ultra-high molecular complexity. In addition, we evaluate the toxicity of the water-soluble photoproducts by use of Microtox bioassay. The results demonstrate that the coal tar sealant contains higher amounts of PAHs and produces abundant water-soluble compounds, relative to unweathered materials, with a high abundance of PAH-like molecules of high toxicity. By comparison, the asphalt sealant produces fewer toxic water-soluble species, with molecular compositions that are consistent with natural dissolved organic matter. These results capture the mass, chemical diversity, toxicity, and source/photoproduct relationship of these compositionally complex emerging contaminants from the built environment.


Assuntos
Alcatrão , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Alcatrão/química , Alcatrão/toxicidade , Ciclotrons , Ecossistema , Análise de Fourier , Hidrocarbonetos , Espectrometria de Massas , Oxigênio/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Água
9.
Int J Hyg Environ Health ; 242: 113971, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35472749

RESUMO

BACKGROUND: Refined coal tar sealant (RCTS) emulsions are used to seal the surface of asphalt pavement. Nine of the 22 polycyclic aromatic hydrocarbons (PAHs) evaluated in this study are classified as known, probable, or possible human carcinogens. Exposure assessment research for RCTS workers has not been published previously. OBJECTIVES: The overall objective of this study was to develop a representative occupational exposure assessment of PAH exposure for RCTS workers based on worksite surveys. The specific aims were to: 1) quantify full-shift airborne occupational exposures to PAHs among RCTS workers; 2) quantify workers' dermal exposures to PAHs; 3) quantify biomarkers of PAH exposure in workers' urine; 4) identify specific job titles associated with RCTS exposure; and 5) apply these results to a biological exposure index to assess risk of potential genotoxicity from occupational exposures. METHODS: A total of twenty-one RCTS workers were recruited from three companies. Personal and area air samples were collected using a modification of NIOSH Method 5515. Dermal exposure was assessed by hand and neck wipes before and after shifts. Twenty-two PAHs were quantified via gas chromatography-mass spectrometry selected ion monitoring. Internal dose was estimated by quantifying select PAH metabolites in pre- and post-shift urine samples using on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. RESULTS: PAH levels in the worker breathing zones were highest for naphthalene, acenaphthene, and phenanthrene, with geometric means of 52.1, 11.4, and 9.8 µg/m3, respectively. Hand wipe levels of phenanthrene, fluoranthene and pyrene were the highest among the 22 PAHs with geometric means of 7.9, 7.7, and 5.5 µg/cm2, respectively. Urinary PAH biomarkers for naphthalene, fluorene, phenanthrene, and pyrene were detected in all workers and were higher for post-shift samples than those collected pre-shift. Urinary concentrations of the metabolite 1-hydroxypyrene were greater than the American Conference of Governmental Industrial Hygienists (ACGIH) Biological Exposure Index (BEI) for this metabolite in 89 percent of post-shift samples collected on the final day of the work week or field survey. Statistically significances were found between concentrations of fluorene, naphthalene, and phenanthrene in the breathing zone of workers and their corresponding urinary PAH biomarkers. Workers were placed in two work place exposure groups: applicators and non-applicators. Applicators had higher total PAH concentrations in personal breathing zone (PBZ) air samples than non-applicators and were more likely to have post-shift hand wipe concentrations significantly higher than pre-shift concentrations. Concentrations of post-shift urinary biomarkers were higher, albeit not significantly, for applicators than non-applicators. CONCLUSIONS: The exposure results from RCTS worker samples cannot be explained by proximal factors such as nearby restaurants or construction. Air and skin concentration levels were substantially higher for RCTS workers than previously published levels among asphalt workers for all PAHs. PAH profiles on skin wipes were more consistent with RCTS sealant product than air samples. Last day post-shift urinary concentrations of 1-hydroxypyrene greatly exceeded the ACGIH BEI benchmark of 2.5 µg/L in 25 of 26 samples, which suggests occupational exposure and risk of genotoxicity. When pyrene and benzo[a]pyrene were both detected, concentration ratios from personal exposure samples were used to calculate the adjusted BEI. Concentrations of 1-hydroxypyrene exceeded the adjusted BEIs for air, hand wipes, and neck wipes in most cases. These results indicate the need to increase safety controls and exposure mitigation for RCTS workers.


Assuntos
Poluentes Ocupacionais do Ar , Alcatrão , Exposição Ocupacional , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Ocupacionais do Ar/análise , Biomarcadores/urina , Alcatrão/análise , Monitoramento Ambiental/métodos , Fluorenos/análise , Humanos , Hidrocarbonetos/análise , Hidrocarbonetos/química , Naftalenos/análise , Exposição Ocupacional/análise , Fenantrenos/urina , Hidrocarbonetos Policíclicos Aromáticos/urina , Pirenos
10.
Artigo em Inglês | MEDLINE | ID: mdl-35457657

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) have been a problem in the environment for an extended period. They are mostly derived from petroleum, coal tar and oil spills that travel and are immobilized in wastewater/water sources. Their presence in the environment causes a hazard to humans due to their toxicity and carcinogenic properties. In the study, coal tar was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) and a concentration of 787.97 mg/L of naphthalene, followed by 632.15 mg/L of phenanthrene were found to be in the highest concentrations in the various water sources such as sewage, alkaline and acid mine drainage. A design column was used to investigate the leaching process and assessments were conducted on 300 mL of the various water sources mentioned, with 5 g of coal tar added and with monitoring for 4 weeks. The influence of the physiochemical properties of the receiving water sources, such as sewage, and acid and alkaline mine drainage, on the release of PAHs from the coal tar was assessed. The acidic media was proven to have the highest release of PAHs, with a total concentration of 7.1 mg/L of released PAHs, followed by 1.2 mg/L for the sewage, and lastly, 0.32 mg/L for the alkaline mine drainage at room temperature.


Assuntos
Alcatrão , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Carvão Mineral/análise , Alcatrão/análise , Monitoramento Ambiental/métodos , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Esgotos/análise , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise
11.
Mini Rev Med Chem ; 22(21): 2702-2725, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35362376

RESUMO

Indole (2,3-benzopyrrole) containing a pyrrolyl ring possesses the characteristic of electron- rich aromatic compounds. Indole occurs in the oil of jasmine and cloves and coal tar. Additionally, it is also present as a putrefaction product from animals' intestines. Notably, indole and its derivatives exhibit a wide range of biological properties, such as anti-Alzheimer's disease, anti-cancer, antibacterial, anti-inflammatory, anti-human immunodeficiency virus (HIV), anti-diabetic, antituberculosis, anti-oxidant, anti-coronavirus, and antifungal activities. In this mini-review, recent advances in biological activities, mechanisms of action, total synthesis, structural modifications, and structure-activity relationships of indole and its derivatives from 2018 to 2020 are described. We hope the present paper can pave the way for future design, development, and application of indole derivatives as potent drugs.


Assuntos
Antifúngicos , Alcatrão , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Indóis/química , Relação Estrutura-Atividade
12.
Environ Sci Technol ; 56(3): 1615-1626, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35045246

RESUMO

Metals and polycyclic aromatic hydrocarbons (PAHs) are common pollutants in urban streambed sediment, yet their occurrence is highly variable and difficult to predict. To investigate sources of PAHs and metals to streambed sediment, we sampled pavement dust, soil, and streambed sediment in 10 urban watersheds in three regions of the United States and applied a fallout-radionuclide-based sediment-source analysis to quantify the pavement dust contribution to stream sediment (%dust). We also mapped the area of sealcoated pavement in each watershed (%sealed) to investigate the role of coal-tar pavement sealant (CTS) as a PAH source. Median total and carbon-normalized total PAH concentrations were significantly higher in streambed sediment in the Northeast (54.3 mg/kg and 2.71 mg/gOC) and Southeast (5.37 mg/kg and 1.36 mg/gOC), where CTS is commonly used, than in the Northwest (2.11 mg/kg and 0.071 mg/gOC), where CTS is rarely used. Generalized additive models indicated that %sealed and in some cases %dust significantly affected total PAH concentrations in streambed sediments. The %dust was a significant variable for common urban metals: Cu, Pb, and Zn. These findings advance our quantitative understanding of the role of pavement dust as a source and a vector of contaminants to urban streams.


Assuntos
Alcatrão , Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Alcatrão/análise , Poeira/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Sedimentos Geológicos , Metais/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Poluentes Químicos da Água/análise
13.
Chemosphere ; 289: 133014, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34864013

RESUMO

Coal tar wastewater is hard to degrade by traditional methods because of its toxic pollutant constituents and high concentration of aromatic hydrocarbons, especially phenolic substances. A new type of hydrophobic benzacetone modified PbO2 anode (BA-PbO2 electrodes) was used for the electrocatalytic treatment of coal tar wastewater in a continuous cycle reactor. The surface morphology, structure, valences of elements, hydrophobicity, hydroxyl radical (·OH) produced capacity, electrochemical properties and stability of BA-PbO2 electrodes were characterized by SEM (scanning electron microscopy), XRD (X-ray diffraction), XPS (X-ray photoelectron spectroscopy), contact angle, a fluorescence probe test, an electrochemical workstation and accelerated life test, respectively. The BA-PbO2 electrodes exhibited a compact structure and finely dispersed crystallize size of 4.6 nm. The optimum degradation conditions of coal tar wastewater were as follows: current density of 90 mA cm-2, electrode gap of 1 cm and temperature at 25 °C with flow velocity of 80 L h-1. The chemical oxygen demand (COD) removal efficiency reached 92.39% after 240 min of degradation under the optimized conditions and the after-treatment COD value was 379.51 mg L-1 which was lower than the centralized emission standard (less than 400 mg L-1). These findings demonstrated the feasibility and efficiency of electrocatalytically degrading coal tar wastewater by BA-PbO2 electrodes. The possible mechanism and pathway for phenol a specific pollutant in coal tar wastewater were investigated by quantum chemistry calculations (Multiwfn) and gas chromatography-mass spectrometry (GC-MS). The toxicity of each intermediate was predicted by the ECOSAR program.


Assuntos
Alcatrão , Poluentes Químicos da Água , Butanonas , Eletrodos , Interações Hidrofóbicas e Hidrofílicas , Chumbo , Oxirredução , Óxidos , Titânio , Águas Residuárias , Poluentes Químicos da Água/análise
14.
Artigo em Inglês | MEDLINE | ID: mdl-34886578

RESUMO

Primary and secondary emissions of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) from a waterproof coal tar membrane and their effect on the indoor air quality were investigated through a case study in a residential building situated in Madrid, Spain. The air contaminants were analyzed in situ using photoionization method and several samples of contaminants were taken using three sorbents: activated carbon, XAD2 and Tenax GR. It was found that various VOCs such as toluene, p- and m-Xylene, PAHs such as naphthalene, methyl-naphthalenes, acenaphthene, acenaphthylene, phenanthrene and fluorine, volatile organic halogens including chloroform and trichlorofluoromethane, and alkylbenzene (1,2,4-trimethylbenzene) were found at concentrations, which exceeded the limits established by international and national agencies (WHO, EPA, OSHA). Some of the above organic compounds were found also in the samples of construction and building materials, which were obtained at different heights and places. The analysis of possible sources of the contaminants pointed at the original coal-tar membrane, which was applied on the terrace to be waterproof. During a posterior reparation the membrane was coated with a new one that hindered dissipation of emitted contaminants. The contaminants leached out and were absorbed by construction materials down in the dwelling. These materials then acted as secondary emission sources. To remediate the emission problem as the contaminated materials were removed and then a ventilation system was installed to force the gasses being emitted from the rest of contaminated slab outside. Follow-up has validated the success of the remediation procedure.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Alcatrão , Hidrocarbonetos Policíclicos Aromáticos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Carvão Mineral , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Compostos Orgânicos Voláteis/análise
15.
J Contam Hydrol ; 243: 103861, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34391967

RESUMO

Thermal enhancement is known to be an efficient way to decrease the residual saturation of some common dense non-aqueous phase liquids (DNAPLs) after pumping. However, the effect of transient heat transfer during the recovery of a high-viscosity contaminant, such as coal tar, in highly permeable porous media is still unknown. A 2D tank experimental setup allowing monitoring of temperature and saturation fields during DNAPL pumping has been developed. Experiments were run under isothermal and non-isothermal conditions, at low and high flow rates. We investigated the presence of viscous fingering and how that influences the shape of the cone of depression, as well as the residual saturation. The saturation fields show that less viscous fingering occurs in pre-heated cases and that heating increases the recovery efficiency. Increasing the temperature increases the critical velocity and the viscosity ratio and helps to stabilize the interface between the non-wetting and wetting phase. Observations were first made on an oil and ethanol fluid pair because its properties were known, before extending the experiments to a coal tar and water fluid pair. Residual oil saturation after pumping was decreased by 6-16% in all pre-heated conditions. Pumping at low flow rate in these conditions leaves the smallest oil residual saturation (20%) after pumping. A low flow rate increases the recovery efficiency by reducing viscous fingering and by spreading the generated heat to a larger part of the tank. Finally, results on coal tar pumping show that the high thermal conductivity of water helps in keeping the temperature high during pumping. The residual coal tar saturation was reduced from 40% at 20 °C to 28% when pre-heating the tank. Operating at a low flow rate and with a uniform temperature is the key to recovering the highest amount of a viscous DNAPL such as coal tar from the soil and satisfying cleanup goals when using thermally enhanced pumping.


Assuntos
Alcatrão , Poluentes Químicos da Água , Porosidade , Viscosidade , Poluentes Químicos da Água/análise
17.
J Drugs Dermatol ; 20(6): 701-702, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34076391

RESUMO

Given the high costs of systemic psoriasis therapies, studies have also shown that phototherapy achieves significant cost savings by replacing or delaying drug-based systemic treatment in patients with moderate to severe disease. However, this modality is often underutilized mainly due to the lack of phototherapy treatment centers across the country. Home phototherapy was designed to fill this treatment gap and allow patients to be treated with phototherapy despite living in areas that may not have a formal treatment facility. Inspired by the Goeckerman regimen, a preliminary pilot study showed that a novel, home phototherapy device utilizing a mobile phone-controlled L.E.D UVB light source and an occlusive hydrogel patch containing coal tar was superior to control as well as both NB-UVB alone and a coal tar dressing alone.Visit the Psoriasis Resource Center for more on this topic.


Assuntos
Alcatrão , Psoríase , Terapia Combinada , Humanos , Projetos Piloto , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Psoríase/radioterapia , Terapia Ultravioleta
18.
J Chromatogr A ; 1651: 462317, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34161836

RESUMO

Unlike native polycyclic aromatic hydrocarbons (PAHs), quantitation of substituted polycyclic aromatic compounds (PACs) has been a challenge in the environmental industry. The challenge can be attributed in part to the large number of theoretically possible isomers and the lack of authentic standards for quantitation. In addition, the lack of a unified approach to the quantitation of these compounds has led to poor interlaboratory accuracy. Because these compounds are often used for toxicology studies or to delineate sources and fingerprinting, it is vital that a standardized approach to quantify them is established. This study evaluated different quantitation approaches to quantify both 16 individual PACs and 32 groups/clusters of substituted PACs in three standard reference materials (SRM 1944 - New York / New Jersey waterway sediments, SRM 1597 - a coal tar sample and SRM 2779 - Gulf of Mexico crude oil). The methods employed include: (1) external calibration taking into account recovery correction factor for each analyte, (2) an average relative response factor (ARRF) of PACs obtained with a recovery correction, (3) ARRF of PACs obtained using uncorrected peak areas (i.e., no recovery correction), (4) ARRF of PACs calculated by normalization to deuterated PAHs and (5) ARRF of native PAHs to quantify substituted PACs. The evaluation of concentrations of individually substituted PACs from the different quantitative approaches compared to the certified/reference values showed that methods 1, 2 and 3 performed best. The average percentage of compounds that fell within our acceptable limit (±30%) using methods 1, 2 and 3 for SRM-1944, -1597a and -2779 was 87, 75 and 100%, respectively. Using native PAHs to quantify their substituted analogs resulted in data of the poorest quality. Irrespective of the approach used, there were significant systematic errors in measurements on clusters/groups PACs most notably C1 and C2-benzanthracenes/ chrysenes/triplenylenes, and C2- and C3-dibenzothiophenes being consistently greater than 100% of the stated value. Commerical availability of more substituted PACs will mitigate the biases associated with the quanititation of PAC clusters/groups.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Alcatrão/análise , Petróleo/análise
19.
Med Clin North Am ; 105(4): 627-641, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34059242

RESUMO

Psoriasis is a systemic inflammatory condition that negatively affects the quality of life and medical health of 125 million individuals globally. Although psoriasis has historically been viewed as a skin-limited disease and managed with topical agents (eg, coal tar, corticosteroids, and vitamin D analogues), the recontextualization of psoriasis as a systemic condition involving multiple organ systems has prompted the development of numerous immunomodulating, systemic agents with more targeted mechanisms of action. This article briefly discusses the indications and nuances of new and developing therapeutic agents for psoriasis management.


Assuntos
Interleucinas/antagonistas & inibidores , Psoríase/patologia , Psoríase/terapia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Administração Tópica , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Ensaios Clínicos como Assunto , Alcatrão/administração & dosagem , Alcatrão/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Humanos , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/uso terapêutico , Inibidores de Janus Quinases/uso terapêutico , Psoríase/diagnóstico , Psoríase/psicologia , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Qualidade de Vida/psicologia , Receptores de Hidrocarboneto Arílico , Vitamina D/administração & dosagem , Vitamina D/análogos & derivados , Vitamina D/uso terapêutico
20.
Dermatol Online J ; 27(2)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33818983

RESUMO

Erythrodermic psoriasis is a relatively rare, more dangerous inflammatory variant of psoriasis associated with high morbidity and mortality. It can be exceptionally challenging to manage, defeating even the most experienced dermatologist's arsenal of treatment strategies. Goeckerman therapy, a regimen of ultraviolet B phototherapy and crude coal tar, has demonstrable efficacy in severe and recalcitrant plaque-type psoriasis. However, its utility in erythrodermic psoriasis has not been explored within the dermatology literature. Herein, we present a patient with a long-standing history of erythrodermic psoriasis refractory to eleven treatment modalities including four biologic agents, who had his erythroderma 'turned around' following Goeckerman therapy. 'Turned around' is used to describe dramatically reducing a patient's cutaneous inflammation so that previously recalcitrant disease can now respond to maintenance therapy. The importance of a one to three week 'cool down' period of topical corticosteroid therapy prior to phototherapy or crude coal tar use is highlighted in this case as well. Although Goeckerman therapy is no longer regularly used, it remains one of the most efficacious treatments available for intractable psoriasis, attracting patients from all over the country desperate for symptom relief. This case suggests it may be useful in 'turning around' extremely difficult-to-treat erythrodermic psoriasis as well.


Assuntos
Alcatrão/uso terapêutico , Dermatite Esfoliativa/terapia , Psoríase/terapia , Terapia Ultravioleta , Terapia Combinada , Dermatite Esfoliativa/complicações , Resistência a Medicamentos , Feminino , Humanos , Masculino , Psoríase/complicações
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