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1.
Forensic Sci Int ; 357: 111988, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520829

RESUMO

In recent years, collection and analysis of condom evidence in sexual assault investigations are becoming more common in forensic caseworks. Condom analysis can provide investigative leads or establish potential contact between the suspect and victim in the absence of DNA evidence or supplement biological evidence. Recent forensic literature shows significant advancements in the analysis of condom lubricants, including casework samples. There is an increasing trend in the use of chemometric tools for the comparison and interpretation of the results. This review highlights the advances in common analytical techniques used for the analysis of condom lubricants with a particular focus on the developments occurring in recent years, including chemometric interpretation. The analysis of reference and casework samples (swab samples, samples on skin, clothing and fingermark) are discussed separately. For casework samples, the transfer and persistence of different lubricant formulations are discussed, along with their detection with various analytical approaches. The issues with the interpretation of lubricants are also discussed in another section, with particular emphasis on samples such as personal hygiene products which have similar formulations with sexual lubricants and the interpretation of negative profiles. The current challenges in the field and prospects for future research are also discussed.


Assuntos
Medicina Legal , Delitos Sexuais , Medicina Legal/métodos , Preservativos , Lubrificantes/análise , Pele/química
2.
J Chromatogr A ; 1713: 464525, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38000198

RESUMO

Lubricating oils help an internal combustion engine function effectively by reducing friction and wear on the engine's moving parts. They typically consist of petroleum-derived base oil and various additives to achieve the desired characteristics in automotive engine oils. Determination of aromatics and polar additives in the finished and used lubricating oils is not possible with existing methods hence their development is significant from the perspectives of environment and reuse/re-refining of used lubricating oils. This study reports the development of a new HPLC method to determine additives in the finished lubricating oils and/or polars in the used engine oils. The proposed method is simple, fast (runtime of 13 min), does not require sample pre-treatment, and exhibits high precision and superior limits of detection and quantification. The method demonstrated good linear response ranging from 0.1 to 30 mass for total aromatics and 0.1 to 20 % for additives. The method validation was carried out by analyzing brand-new commercial two and four-wheeler lubricants with used automotive lubricants. Based on the proposed method, the aromatics and additives concentration ranges in the studied finished lubricants were estimated between 0.20-1.70 % (mass) and 0.20-3.50 % (mass), respectively. Similarly, for used lubricants, the aromatics and additives were estimated to be 1.00-6.10 % and 0.60-2.40 % (mass), respectively.


Assuntos
Hidrocarbonetos Aromáticos , Petróleo , Cromatografia Líquida de Alta Pressão , Óleos , Petróleo/análise , Lubrificantes/análise , Lubrificantes/química
3.
Adv Colloid Interface Sci ; 311: 102814, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36446286

RESUMO

Osteoarthritis is the most common degenerative and highly prevalent joint disease, characterized by progressive loss and destruction of articular cartilage. The damaged cartilage surface has an increased friction, which causes patients to suffer from serious pain. Restoring the lubrication ability of the joint is central to the treatment of osteoarthritis, a key topic in medical research. A variety of lubricants have been designed to reduce friction in joints and promote cartilage tissue repair to alleviate the symptoms of osteoarthritis. Herein, we review the recent progress of lubricants from the three perspectives of natural, bioinspired, and alternative strategies for osteoarthritis treatment, as well as the structural characterization and lubrication properties of such lubricants. Specifically, natural lubricants include glycosaminoglycans, lubricin and lipids in joints, bioinspired lubricants include scaffolds mimicking hyaluronic acid or lubricin, and alternative lubricants include modified lubricants based on hyaluronic acid, lipids, nanoparticles, and peptides. We also discuss the current challenges and long-term perspectives for further research in this area.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Ácido Hialurônico/química , Lubrificantes/análise , Lubrificantes/química , Osteoartrite/tratamento farmacológico , Cartilagem Articular/química , Lipídeos/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-35134664

RESUMO

Lubricating oils are composed of base oils (>85% v/v) and enriching additives (<15% v/v). Three types of base oils may be distinguished: 1) traditional bases (obtained by low-volatile fractions from crude oil distillation refining), 2) synthetic bases (mainly poly-alpha-olefins, sometimes esters, especially succinic acid esters), 3) bases of natural origin (especially obtained from refined plant oils). The bases of natural origin are the only ones recommended for application when lubricating oil may be emitted to the environment (e.g. when the machine with an open cutting system is used). Group-type separation and analysis of group-type composition of base and lubricating oils are of significant importance in quality control and environmental monitoring. Due to the potentially wide range of polarity of the components of base and lubricating oils, group- type separation becomes a difficult separation problem. It is also a serious analytical problem due to the considerable diversity of physicochemical properties. The authors propose a new procedure for the separation and determination of the group-type composition of base and lubricating oils using thin-layer liquid chromatography in normal phase systems (abr. NP-TLC) on silica gel plates impregnated with berberine salt/in the coupling of thin-layer chromatography with flame ionization detection (abr. TLC-FID). A new, effective procedure of TLC plates impregnation with berberine sulphate was presented. The proposed procedure ensures the visualization of all groups of base oils. Extensive experimental research showed that a 2-step development procedure with application of n-hexane up to 100% height of development +15 min and further n-hexane: isopropanol: tri-fluoroacetic acid 96.25: 3: 0.75 (v: v: v) up to 75% height of development is advantageous for the group-type separation, both in TLC-FID and TLC.


Assuntos
Cromatografia em Camada Fina/métodos , Lubrificantes , Óleos , Petróleo/análise , Berberina/química , Ionização de Chama , Lubrificantes/análise , Lubrificantes/química , Lubrificantes/isolamento & purificação , Óleos/análise , Óleos/química , Óleos/isolamento & purificação
5.
Forensic Sci Int ; 325: 110847, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34098472

RESUMO

Condom evidence has become in the past years a very relevant item of evidence in sexual assault or rape cases, being an objective help in the reconstruction of the activity. Traces recovered from a vaginal swab might help to identify whether a condom or other lubricants were used, and thereby possibly confirming or infirming allegations of the parties. However, the interpretation of condom traces can be challenging and requires a detailed understanding of various factors like condom lubricant chemical composition and occurrence on the market, transfer and persistence parameters and background. Herein, we aimed at improving our understanding of factors affecting the transfer variability of condom residues recovered from vaginal matrix. This work employed Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) to provide new data for a characterization of condom lubricants and their traces after a transfer in a vaginal matrix has occurred. Condom traces were recovered from volunteers and the traces characteristics were investigated and analyzed. The effects of donor (condom) and receiver (vaginal matrix) were firstly evaluated, as they are known factors, and these data that could be obtained in real caseworks. Using principal component analysis (PCA), this study highlighted that the effect of the donor was more important than the receiver effect. Vaginal matrix residues were not detected in transferred extracts. The discrimination pattern amongst the donor was found to be indistinguishable from the one obtained on reference material using ATR-FTIR (Attenuated Total Reflectance).


Assuntos
Preservativos , Lubrificantes/análise , Vagina/química , Coito , Feminino , Ciências Forenses , Humanos , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Environ Sci Pollut Res Int ; 28(26): 33828-33836, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32535829

RESUMO

The advancements in electricity production and distribution, as well as the growing consumption of electrical energy, have made electrical equipment a vital part of the technological infrastructure. On the other hand, the necessity for environmentally safe and sustainable solutions is another requirement for electrical transformers, the same as for every technology and equipment nowadays. In this aspect, the main challenges in electrical transformers are the reduction in power losses, the use of construction materials with minimum environmental impact, and the elongation of their service life. All three challenges are related to the insulating oils that are used in the transformers which are exclusively mineral based and are products of crude oil. Mineral oils can almost be fully recyclable and can be regenerated with satisfactory results. However, they are not biodegradable, they are flammable, and they may present toxic properties for both humans and the environment. Bio-based lubricants are fully recyclable and can be regenerated, they have none of the hazardous properties of mineral oils, and are fully biodegradable. Furthermore, they are considered a sustainable solution, since they are not fossil-based but products of cultivation and the supplies can be considered indefinite. This paper tries to present an assessment of the environmental impact of vegetable-based insulating oils for electrical transformers, in the wider view of sustainability global efforts, considering additional environmental impact compared with the already used in related works. The assessment is executed for the whole life cycle of two product groups of transformers, as determined by the EU Eco Design Directive 2009/125/EC and the EU Regulation 548/2014 on eco design of requirements on transformers.


Assuntos
Petróleo , Óleos de Plantas , Humanos , Lubrificantes/análise , Óleo Mineral/análise , Verduras
7.
J Forensic Sci ; 65(5): 1767-1773, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32615002

RESUMO

DNA analysis has been widely used in the forensic field in order to contribute to identifying the perpetrator of a crime. Forensic investigation in sexual assaults usually focuses on locating and identifying biological fluids, followed by DNA analysis. The identification of certain compounds present in condoms can be useful to reconstruct the occurred event, especially in cases of sexual assaults where the DNA analysis did not show the presence of a male profile and where RNA analysis did not show the presence of sperm markers. Herein we describe the case of a woman reporting to be victim of sexual assault, who was not able to provide accurate information concerning the dynamics of the event; she remembered only forced penile-vaginal penetration by a single perpetrator. We performed short tandem repeat (STR) analyses and mRNA typing for forensic genetics testing on vaginal and rectal swabs collected on the victim, and Fourier-transform infrared spectroscopy (FTIR) followed by chromatographic analyses for the detection of condom compounds on the same swabs. The STR analysis showed only the victim's genetic profile, and RNA analysis showed only the presence of vaginal and skin markers. In this situation, the identification of condom compounds residues on vaginal swabs became important as it complemented other collected evidences allowing the Court to reconstruct the events. A proposal of likelihood ratio (LR) calculation for the assessment of the weight of evidence in this case is described.


Assuntos
Preservativos , Dimetilpolisiloxanos/análise , Funções Verossimilhança , Lubrificantes/análise , Estupro , Vagina/química , Adulto , Impressões Digitais de DNA , Feminino , Medicina Legal , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Repetições de Microssatélites , RNA Mensageiro/análise , Manejo de Espécimes , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Environ Pollut ; 255(Pt 1): 113190, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31541828

RESUMO

Microbial diversity in machine oil contaminated soil was determined by high-throughput amplicon sequencing technology. The diversity of culturable microbes in the contaminated soil was further characterized using polymerase chain reaction method. Proteobacteria and Bacteroidetes were the most dominant phyla and occupied 52.73 and 16.77%, respectively, while the most abundant genera were Methylotenera (21.62%) and Flavobacterium (3.06%) in the soil. In the culturable microbes, the major phyla were Firmicutes (46.15%) and Proteobacteria (37.36%) and the most abundant genera were Bacillus (42.86%) and Aeromonas (34.07%). Four isolated microbes with high machine oil degradation efficiency were selected to evaluate their characteristics on the oil degradation. All of them reached their highest oil degradation rate after 7 days of incubation. Most of them significantly increased their oil degradation rate by additional carbon or organic nitrogen source in the incubation medium. The oil degradation rate by combination of the four microbes at the same inoculation level was also higher than the rate from each individual microbe. The protocol and findings of this study are very useful for developing micro-bioremediation method to eliminate machine oil contaminants from soil.


Assuntos
Bacteroidetes/metabolismo , Óleos/análise , Petróleo/análise , Proteobactérias/metabolismo , Poluentes do Solo/análise , Solo/química , Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação , Biodegradação Ambiental , Carbono/análise , Lubrificantes/análise , Nitrogênio/análise , Proteobactérias/classificação , Proteobactérias/isolamento & purificação , Microbiologia do Solo
9.
Forensic Sci Int ; 302: 109861, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31265983

RESUMO

Today, rape and sexual assault cases are mainly solved using evidence such as medical evidence or DNA analysis. Condom traces have been found to be present in 10% of assaulted women, when no DNA is found [1]. Numerous studies have emphasized the interest of analysing the composition of male condoms and their traces, and developing specific methods for the analysis of this type of evidence. However, transfer and persistence of condom traces in a specific matrix are rarely referenced. Therefore, forensic scientists have no complete knowledge of the trace and what could be expected in a real case. The purpose of this article is to review the literature addressing the composition of condoms and their traces as well as its influence on the transfer and persistence from a forensic point of view. Peer-reviewed literature, patents, professional literature, data from international administrations and international organisations' reports have been used to track the composition and the problematics of transfer and persistence of condom traces. The results of this review show that the composition of male condoms and their traces are complex systems, with numerous compounds originating from the condom at the moment of the transfer and evolving over time according to specific persistence patterns. Although numerous types of analyses have already been proposed and tested for condom traces, forensic evidence considerations have not been fully studied yet. Considering the fact that sexual assaults without the detection of DNA are increasingly frequent, there is a definite medical and forensic need to improve our knowledge of the processes involved in the development of condom traces in order to better understand analytical results.


Assuntos
Preservativos , Delitos Sexuais , Vagina/química , Anestésicos Locais/análise , Antioxidantes/análise , Dimetilpolisiloxanos/análise , Feminino , Aromatizantes/análise , Medicina Legal , Humanos , Látex/análise , Lubrificantes/análise , Masculino , Nitrosaminas/análise , Odorantes/análise , Polietileno/análise , Polietilenoglicóis/análise , Pós , Conservantes Farmacêuticos/análise , Espermicidas/análise , Amido/análise
10.
Environ Sci Pollut Res Int ; 26(23): 23257-23267, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31197668

RESUMO

The low-cost Ca-bentonite was rapidly converted to a mesoporous adsorbent via microwave-assisted acidification and the obtained materials were employed for the removal of contaminants from waste lubricant oil. In order to understand the role of acid combinations on activation, the agent compositions were prepared according to the mixture design algorithm. The waste oil recovery was carried out in a batch system to determine the appropriate acid composition, optimum microwave power, radiation time, and powder/acid ratio. As power increased, the contaminant removal performance of the adsorbent was effectively raised to achieve appropriate clear base oil. The rise in power behind 600 W negatively affected the performance of the adsorbent in which the color of oil was changed from yellow to brown. The appropriate recovery of waste oil was readily achieved by employment of adsorbents in which the acidification was performed in 15 min. The microwave-assisted technique could shorten the residence time to achieve the maximum efficiency in comparison with the performance of those produced through the conventional method. Although sulfuric acid can be used for acidification of bentonite by microwave heat treatment, the combination of acetic acid, < 50 mol%, with the mentioned acid was identified as an efficient agent to improve the performance of adsorbents which is valuable from an engineering point of view.


Assuntos
Bentonita/química , Poluentes Ambientais/análise , Lubrificantes/análise , Micro-Ondas , Nanopartículas/química , Resíduos/análise , Adsorção , Porosidade
11.
Talanta ; 194: 563-575, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30609574

RESUMO

The rapid and accurate identification of condom-derived lubricant traces takes on heightened importance in sexual assault cases where the assailant has used a condom in order to avoid leaving behind incriminating DNA evidence. Previous reports have demonstrated that a variety of techniques can be used to confirm that a given residue is condom-derived, based on the detection of spermicides, slip agents and/or other common additives. However, limited success has been achieved in differentiating brands from among a broad range of condom types. In this study, the utility of direct analysis in real time-high resolution mass spectrometry (DART-HRMS) combined with chemometrics, for the rapid and accurate attribution of brands to condom residues of various types, was explored and developed. A database of condom residue spectra comprised of 110 different condom types representing 16 brands was generated, with the spectra serving as representative fingerprints for each brand. The spectral fingerprints were subjected to pre-processing prior to the application of Partial Least Squares-Discriminant Analysis (PLS-DA) which was used to generate a classifier that permitted identification of condom brands with an accuracy of 97.4%. An additional criterion was imposed on the PLS-DA to provide the confidence level and credibility of each prediction. The effect of time since deposition, the presence of contaminants and the influence of residue transfer on the prediction accuracy of the model were also assessed. The results from Sparse Discriminant Analysis (SDA) and PLS-DA were followed by application of the Student's t-test to determine m/z values representative of small-molecule markers that were most important for defining brand classes. The m/z values revealed by the two methods were found to be consistent in indicating which masses were representative of markers. The SDA method also provided low-dimensional views of the discriminative directions for classification of condom residues, thereby enabling easy visualization of the relationship between the indicated m/z values and brand discrimination. The results further revealed a subset of 14 m/z values that were observed in all 110 condoms representing the 16 brands, and some of these may serve as potential universal small-molecule condom markers. Overall, the results show that the DART-HRMS database of condom residue spectra can be used to identify residues based on differences in chemical components peculiar to each brand. The database can be readily expanded to include more condoms.


Assuntos
Preservativos , Medicina Legal , Informática , Lubrificantes/análise , Espectrometria de Massas , Análise Discriminante , Análise dos Mínimos Quadrados , Análise Multivariada , Delitos Sexuais , Fatores de Tempo
12.
Molecules ; 23(8)2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30110901

RESUMO

Lubricants that are based on renewable raw materials have drawn increased attention in various applications, especially those related to the food industry. Due to the high requirements of environmental protection, there is a need to develop biodegradable base oils that are environmentally friendly and do not contain harmful components. The objective of the research was to obtain a base oil with a certain viscosity and certain desired lubricating properties. Base oils were obtained from Crambe abyssinica oil by means of blending with synthetic oil and oxidation. The oxidation processes were carried out in the presence of N-hydroxyphthalimide with or without CO2 as a solvent. As a final result of this study, oil bases meeting the viscosity requirements and showing suitable lubricating properties were obtained. The Raman spectra of the obtained oils were evaluated.


Assuntos
Lubrificantes/química , Óleos de Plantas/química , Verduras/química , Dióxido de Carbono/química , Catálise , Lubrificantes/análise , Estrutura Molecular , Oxirredução , Oxigênio/química , Óleos de Plantas/análise , Reologia , Análise Espectral Raman , Temperatura , Viscosidade
13.
Environ Monit Assess ; 190(2): 72, 2018 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-29318393

RESUMO

Environmental contamination caused by leakage of fuels and lubricant oils at gas stations is of great concern due to the presence of carcinogenic compounds in the composition of gasoline, diesel, and mineral lubricant oils. Chromatographic methods or non-selective infrared methods are usually used to assess soil contamination, which makes environmental monitoring costly or not appropriate. In this perspective, the present work proposes a methodology to identify the type of contaminant (gasoline, diesel, or lubricant oil) and, subsequently, to quantify the contaminant concentration using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and multivariate methods. Firstly, gasoline, diesel, and lubricating oil samples were acquired from gas stations and analyzed by gas chromatography to determine the total petroleum hydrocarbon (TPH) fractions (gasoline range organics, diesel range organics, and oil range organics). Then, solutions of these contaminants in hexane were prepared in the concentration range of about 5-10,000 mg kg-1. The infrared spectra of the solutions were obtained and used for the development of the pattern recognition model and the calibration models. The partial least square discriminant analysis (PLS-DA) model could correctly classify 100% of the samples of each type of contaminant and presented selectivity equal to 1.00, which provides a suitable method for the identification of the source of contamination. The PLS regression models were developed using multivariate filters, such as orthogonal signal correction (OSC) and general least square weighting (GLSW), and selection variable by genetic algorithm (GA). The validation of the models resulted in correlation coefficients above 0.96 and root-mean-square error of prediction values below the maximum permissible contamination limit (1000 mg kg-1). The methodology was validated through the addition of fuels and lubricating oil in soil samples and quantification of the TPH fractions through the developed models after the extraction of the analytes by the EPA 3550 method adapted by the authors. The recovery percentage of the analytes was within the acceptance limits of ASTM D7678 (70-130%), except for one sample (69% of recovery). Therefore, the methodology proposed here provides faster and less costly analyses than the chromatographic methods and it is adequate for the environmental monitoring of soil contamination by gas stations.


Assuntos
Monitoramento Ambiental/métodos , Poluição por Petróleo , Petróleo/análise , Solo/química , Calibragem , Cromatografia Gasosa , Gasolina/análise , Hidrocarbonetos/análise , Análise dos Mínimos Quadrados , Lubrificantes/análise , Óleos , Espectroscopia de Infravermelho com Transformada de Fourier
14.
J AOAC Int ; 100(4): 922-934, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28623655

RESUMO

This paper concerns the possibility of using TLC coupled with a flame ionization detector (FID) and micro-TLC (µTLC) as precursors for microfluidized devices of analytical techniques to identify and determine the presence and content of the petroleum/vegetable oil base in the lubricating oils applied in cutting devices (chainsaws). This research is related to the problem of ensuring, in compliance with the requirements of environmental protection, a sufficient level of biodegradability of lubricating oils emitted to the environment during operation of equipment lubricated with these oils. Such oils include those mainly used in cutting devices and emitted in the form of a mist into the environment during the operation of those devices. When oil components are eco-toxic, contamination of the environment occurs. New methodologies for the identification and determination of the petroleum oil base, which is very difficult to biodegrade, as well as the easily biodegradable ingredients of vegetable origin in the lubricating oils, are presented. The described procedures indicate in an indisputable way whether the oil contains the oil base originating from crude oil and whether it contains adequate enriching additives. The procedures also allow the assessment of the content of particular groups of constituents (µTLC) or the determination of the group composition (TLC-FID).


Assuntos
Cromatografia/métodos , Ionização de Chama , Lubrificantes/análise , Óleos/análise , Petróleo/análise
15.
Arch Microbiol ; 199(6): 839-851, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28289787

RESUMO

Used lubricating oil (ULO) is a widespread contaminant, particularly throughout tropical regions, and may be a candidate for bioremediation. However, little is known about the biodegradation potential or basic microbial ecology of ULO-contaminated soils. This study aims to determine the effects of used ULO on bacterial community structure and diversity. Using a combination of culture-based (agar plate counts) and molecular techniques (16S rRNA gene sequencing and DGGE), we investigated changes in soil bacterial communities from three different ULO-contaminated soils collected from motorcycle mechanical workshops (soil A, B, and C). We further explored the relationship between bacterial community structure, physiochemical soil parameters, and ULO composition in three ULO-contaminated soils. Results indicated that the three investigated soils had different community structures, which may be a result of the different ULO characteristics and physiochemical soil parameters of each site. Soil C had the highest ULO concentration and also the greatest diversity and richness of bacteria, which may be a result of higher nutrient retention, organic matter and cation exchange capacity, as well as freshness of oil compared to the other soils. In soils A and B, Proteobacteria (esp. Gammaproteobacteria) dominated the bacterial community, and in soil C, Actinobacteria and Firmicutes dominated. The genus Enterobacter, a member of the class Gammaproteobacteria, is known to include ULO-degraders, and this genus was the only one found in all three soils, suggesting that it could play a key role in the in situ degradation of ULO-contaminated tropical Thai soils. This study provides insights into our understanding of soil microbial richness, diversity, composition, and structure in tropical ULO-contaminated soils, and may be useful for the development of strategies to improve bioremediation.


Assuntos
Bactérias/metabolismo , Biodiversidade , Lubrificantes/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Lubrificantes/análise , RNA Ribossômico 16S/genética , Solo/química , Poluentes do Solo/análise , Clima Tropical
16.
Chemosphere ; 171: 491-501, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28038421

RESUMO

The chemical properties of poly- and perfluoroalkyl substances (PFASs) make them widespread for use in a number of industrial and commercial products to confer water and oil-repellency characteristics and to reduce surface tension e.g. in aqueous film-forming foams (AFFFs). Some PFASs, especially perfluoroctane sulfonate, and several perfluoroalkyl carboxylic acids, are known to cause significant human and environmental negative impact. Our knowledge on the content of PFASs in products remains scarce due to limited information available, thus impeding any precise assessment of human exposure and environmental release upon use. This study aimed at analyzing a wide variety of liquid products (n = 194) likely to contain PFASs, including impregnating agents, lubricants, cleansers, polishes, AFFFs and other industrial products. By means of LC- and GC-MS/MS analytical techniques, 24 PFASs (from 41 targeted PFASs) were detected and quantified in 55% of samples. PFAS quantification and profiling was found to be consumer product specific. PFASs were mostly detected in AFFF (90%) and impregnating agents (60%) with mainly ionic and neutral species, respectively. In particular, the fluorotelomer alcohols 6:2, 8:2 and 10:2 FTOHs were detected in 40-50% of impregnating agents. Further investigation by Fast Atom Bombardment Mass Spectrometry (FAB-MS) on a set of AFFF samples allowed the characterization of 8 different PFAS classes as major components in these formulations. Results demonstrated that numerous and diversified PFAS are currently used in specific commercial products, implying significant human exposure and environmental release that necessitate further research concerning their toxicological impact.


Assuntos
Ácidos Alcanossulfônicos/análise , Ácidos Carboxílicos/análise , Fluorocarbonos/análise , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Produtos Domésticos/análise , Lubrificantes/análise , Espectrometria de Massas em Tandem
17.
Chemosphere ; 164: 558-567, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27627466

RESUMO

Lubricant and diesel oil-polluted sites are difficult to remediate because they have less volatile and biodegradable characteristics. The goal of this research was to evaluate the potential of applying an enhanced landfarming to bioremediate soils polluted by lubricant and diesel. Microcosm study was performed to evaluate the optimal treatment conditions with the addition of different additives (nutrients, addition of activated sludge from oil-refining wastewater facility, compost, TPH-degrading bacteria, and fern chips) to enhance total petroleum hydrocarbon (TPH) removal. To simulate the aerobic landfarming biosystem, air in the microcosm headspace was replaced once a week. Results demonstrate that the additives of activated sludge and compost could result in the increase in soil microbial populations and raise TPH degradation efficiency (up to 83% of TPH removal with 175 days of incubation) with initial (TPH = 4100 mg/kg). The first-order TPH degradation rate reached 0.01 1/d in microcosms with additive of activated sludge (mass ratio of soil to inocula = 50:1). The soil microbial communities were determined by nucleotide sequence analyses and 16S rRNA-based denatured gradient gel electrophoresis. Thirty-four specific TPH-degrading bacteria were detected in microcosm soils. Chromatograph analyses demonstrate that resolved peaks were more biodegradable than unresolved complex mixture. Results indicate that more aggressive remedial measures are required to enhance the TPH biodegradation, which included the increase of (1) microbial population or TPH-degrading bacteria, (2) biodegradable carbon sources, (3) nutrient content, and (4) soil permeability.


Assuntos
Bactérias/metabolismo , Hidrocarbonetos/metabolismo , Lubrificantes/metabolismo , Poluição por Petróleo/análise , Petróleo/metabolismo , Poluentes do Solo/metabolismo , Bactérias/genética , Biodegradação Ambiental , Lubrificantes/análise , Petróleo/análise , RNA Ribossômico 16S , Esgotos/microbiologia , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Taiwan
19.
J Mass Spectrom ; 50(5): 749-55, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26259658

RESUMO

Desorption electrospray ionization mass spectrometry (DESI-MS) and easy ambient sonic-spray ionization mass spectrometry (EASI-MS) are employed here in the forensic analysis of chemical compounds found in condoms and relative traces, and their analytical performances are compared. Statistical analysis of data obtained from mass spectra only was applied in order to obtain classification rules for distinguishing ten types of condoms. In particular, two supervised chemometric techniques [linear discriminant analysis (LDA) and soft independent modeling of class analogy (SIMCA)] were carried out on absolute and relative intensity values to test the performances of statistical models in terms of predictive capacity. The achieved classification of samples was excellent because of the high prediction percentages of the method used both for DESI and EASI mass spectrometry analyses, confirming these two as potential ambient ionization techniques for forensic analyses in case of sexual assault crimes. EASI-MS showed 99% prediction ability for LDA using relative data and 100% prediction ability for SIMCA using both absolute and relative ones, while DESI showed 94% prediction ability for both LDA and SIMCA. The absence of any sample preparation technique gives advantages in terms of sample preservation and reduced contamination, allowing successive analyses to be performed on the same sample by other techniques.


Assuntos
Preservativos , Medicina Legal/métodos , Delitos Sexuais , Espectrometria de Massas por Ionização por Electrospray/métodos , Análise Discriminante , Humanos , Lubrificantes/análise , Lubrificantes/química , Modelos Estatísticos , Polímeros/análise , Polímeros/química , Espermicidas/análise , Espermicidas/química
20.
Int J Pharm ; 492(1-2): 258-63, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26196275

RESUMO

HPMC capsules are made by a dipping process and a surface lubricant for the mould pins is an essential processing aid for removing dried capsules shells. For the purpose of this study, the level was determined by quantifying methyloleate (MO) a component found in the lubricant but not in the hypromellose capsules. Here we investigated the influence of the lubricant, low (10.81 µg/capsule=60 mg/kg MO), medium (15.97 µg/capsule=90 mg/kg MO) and high (23.23 µg/capsule=127 mg/kg MO) content on powder (binary mixture of salbutamol: lactose, 1:50 w/w) aerosolization properties was investigated. Results indicated significantly lower emitted dose from capsules with 60 mg/kg MO. Furthermore, the 90 and 127 mg/kg MO level of lubricant capsules produced almost double the Fine Particle Dose & Fine Particle Fraction compared with the low level of lubricant. The data indicates that lubricant level within capsules has an influence on deposition profiles and amount of drug remaining in capsule and inhaler device after actuation. It is suggested lubricant levels greater than 60 mg/kg MO per capsule are required to minimise powder retention within capsules and maximise deposition profiles. AFM (atomic force microscopy) data suggest that internal surface roughness may be related with this phenomena.


Assuntos
Inaladores de Pó Seco , Derivados da Hipromelose/química , Lubrificantes/química , Ácidos Oleicos/química , Aerossóis , Albuterol/química , Cápsulas , Lactose/química , Lubrificantes/análise , Ácidos Oleicos/análise
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