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2.
J Agric Food Chem ; 72(5): 2482-2491, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38264997

RESUMO

In a previously published study, the authors devised a molecular topology QSAR (quantitative structure-activity relationship) approach to detect novel fungicides acting as inhibitors of chitin deacetylase (CDA). Several of the chosen compounds exhibited noteworthy activity. Due to the close relationship between chitin-related proteins present in fungi and other chitin-containing plant-parasitic species, the authors decided to test these molecules against nematodes, based on their negative impact on agriculture. From an overall of 20 fungal CDA inhibitors, six showed to be active against Caenorhabditis elegans. These experimental results made it possible to develop two new molecular topology-based QSAR algorithms for the rational design of potential nematicides with CDA inhibitor activity for crop protection. Linear discriminant analysis was employed to create the two algorithms, one for identifying the chemo-mathematical pattern of commercial nematicides and the other for identifying nematicides with activity on CDA. After creating and validating the QSAR models, the authors screened several natural and synthetic compound databases, searching for alternatives to current nematicides. Finally one compound, the N2-(dimethylsulfamoyl)-N-{2-[(2-methyl-2-propanyl)sulfanyl]ethyl}-N2-phenylglycinamide or nematode chitin deacetylase inhibitor, was selected as the best candidate and was further investigated both in silico, through molecular docking and molecular dynamic simulations, and in vitro, through specific experimental assays. The molecule shows favorable binding behavior on the catalytic pocket of C. elegans CDA and the experimental assays confirm potential nematicide activity.


Assuntos
Amidoidrolases , Caenorhabditis elegans , Nematoides , Animais , Caenorhabditis elegans/metabolismo , Simulação de Acoplamento Molecular , Antinematódeos/química , Quitina/metabolismo
3.
Food Chem Toxicol ; 182: 114120, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37944785

RESUMO

Understanding the mechanisms of mycotoxin toxicity is crucial for establishing effective guidelines and preventive strategies. In this study, machine learning models based on quantitative structure-activity relationship (QSAR) were employed to predict the lipid peroxidation activity of mycotoxins. Two different algorithms using Linear Discriminant Analysis (LDA) and Artificial Neural Networks (ANNs) have been trained using a dataset of 70 mycotoxins. The LDA model had an average correct classification rate of 91%, while the ANN model achieved a perfect 100% classification rate. Following an internal validation process, the models were utilized to predict mycotoxins with known lipid peroxidation activity. The machine learning models achieved an 88% correct classification rate for these mycotoxins. Finally, by utilizing classified algorithms, the study aimed to infer the mechanism of action related to lipid peroxidation for 91 unstudied mycotoxins. These models provide a fast, accurate, and cost-effective means to assess the potential toxicity and mechanism of action of mycotoxins. The findings of this study contribute to a comprehensive understanding of mycotoxin toxicology and assist researchers and toxicologists in evaluating health risks associated with mycotoxin exposure and developing appropriate preventive strategies and potential therapeutic interventions to mitigate the effects of mycotoxins.


Assuntos
Micotoxinas , Relação Quantitativa Estrutura-Atividade , Peroxidação de Lipídeos , Micotoxinas/toxicidade , Redes Neurais de Computação , Algoritmos , Aprendizado de Máquina
4.
Anal Bioanal Chem ; 415(29-30): 7197-7209, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870584

RESUMO

An analytical methodology based on ultrasound-assisted extraction (UAE) followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has been developed for the identification and quantification of 9 authorized herbicides in soil (dimethenamid-P, imazamox, S-metolachlor, nicosulfuron, pendimethalin, prosulfuron, bentazone, terbuthylazine, and mesotrione). Preliminary experiments dealing with solvent extraction, the extraction technique, and herbicide response comparison in soil, with and without organic amendments, were carried out with the purpose of obtaining high sample throughput and sensitivity. UAE and the solvent mixture water:methanol demonstrated higher efficiency and they were selected as sample treatment and extraction solvent, respectively. Critical parameters affecting UAE were optimized by experimental design. In the present research, the extraction technique used in the official EPA microwave-assisted extraction (MAE) methodology (United States Environmental Protection Agency) and UAE optimized methodology were compared. The results indicated that the developed method showed better efficacy since microwave extraction gave very poor responses for nicosulfuron and prosulfuron. The temperature extraction was also optimized; room temperature was the most suitable to work with. Under the optimized conditions, the proposed UAE-LC-MS/MS method was assessed in terms of linearity (R2 ≥ 0.9912), accuracy (recoveries around 100%), and precision (relative standard deviation, RSD < 13%). The absence of significant matrix effects allowed quantification in real samples by external calibration with standards prepared in water:methanol. Method sustainability was also evaluated using the metric tool AGREEPrep. Finally, the analysis of real contaminated samples revealed the presence of 7 out of the 9 studied herbicides with S-metolachlor at high concentrations in all samples.


Assuntos
Herbicidas , Cromatografia Líquida/métodos , Herbicidas/análise , Espectrometria de Massas em Tandem/métodos , Metanol , Solo , Solventes/análise , Água/análise , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida
5.
Methods Protoc ; 6(5)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37888027

RESUMO

Hydroalcoholic gels or hand sanitisers have become essential products to prevent and mitigate the transmission of COVID-19. Depending on their use, they can be classified as cosmetics (cleaning the skin) or biocides (with antimicrobial effects). The aim of this work was to determine sixty personal care products frequently found in cosmetic formulations, including fragrance allergens, synthetic musks, preservatives and plasticisers, in hydroalcoholic gels and evaluate their compliance with the current regulation. A simple and fast analytical methodology based on solid-phase microextraction followed by gas chromatography-tandem mass spectrometry (SPME-GC-MS/MS) was validated and applied to 67 real samples. Among the 60 target compounds, 47 of them were found in the analysed hand sanitisers, highlighting the high number of fragrance allergens (up to 23) at concentrations of up to 32,458 µg g-1. Most of the samples did not comply with the labelling requirements of the EU Regulation No 1223/2009, and some of them even contained compounds banned in cosmetic products such as plasticisers. Method sustainability was also evaluated using the metric tool AGREEPrep, demonstrating its greenness.

6.
J Cell Mol Med ; 27(15): 2249-2260, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37403218

RESUMO

In the present study, the identification of potential α-amylase inhibitors is explored as a potential strategy for treating type-2 diabetes mellitus. A computationally driven approach using molecular docking was employed to search for new α-amylase inhibitors. The interactions of potential drugs with the enzyme's active site were investigated and compared with the contacts established by acarbose (a reference drug for α-amylase inhibition) in the crystallographic structure 1B2Y. For this active site characterization, both molecular docking and molecular dynamics simulations were performed, and the residues involved in the α-amylase-acarbose complex were considered to analyse the potential drug's interaction with the enzyme. Two potential α-amylase inhibitors (AN-153I105594 and AN-153I104845) have been selected following this computational strategy. Both compounds established a large number of interactions with key binding site α-amylase amino acids and obtained a comparable docking score concerning the reference drug (acarbose). Aiming to further analyse candidates' properties, their ADME (absorption, distribution, metabolism, excretion) parameters, druglikeness, organ toxicity, toxicological endpoints and median lethal dose (LD50 ) were estimated. Overall estimations are promising for both candidates, and in silico toxicity predictions suggest that a low toxicity should be expected.


Assuntos
Acarbose , Diabetes Mellitus Tipo 2 , Humanos , Acarbose/farmacologia , Acarbose/química , Acarbose/uso terapêutico , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Avaliação Pré-Clínica de Medicamentos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , alfa-Amilases
7.
Sci Total Environ ; 857(Pt 2): 159485, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36257444

RESUMO

Recycled tire crumb rubber (RTCR) surfaces contain harmful and carcinogenic substances, which can be ingested by the users of these facilities, mainly athletes and children. In this work, the potential in-vitro oral bioaccessibility of eighteen polycyclic aromatic hydrocarbons (PAHs) from RTCR employed as infill in synthetic football fields was studied in human synthetic body fluids (saliva, gastric, duodenal and bile), prepared according the Unified Bioaccessibility Method. Solid-phase extraction (SPE) using commercial sorbents and a new green material based on cork (cork industry by-product) were used to isolate the bioaccessible PAHs before gas chromatography-tandem mass spectrometry analysis. The method was optimized and validated attending the analytical figures of merit. The feasibility of cork biosorbent for the extraction of the compounds was demonstrated, as well as the suitability of the UBM method to perform the digestion with good precision. The application to real samples collected from football fields demonstrated the presence of 17 of the 18 target PAHs in the biofluids. Most volatile PAHs such as NAP, ACY, ACE, FLU, PHN and ANC, achieved the highest bioaccessibility percentage levels. The carcinogenic B[a]P was detected in 75 % of the samples at concentrations up to 2.5 ng g-1 (bioaccessible fraction). Children exposure assessment was carried out to identify potential risk. Other hazardous and environmentally problematic compounds such as N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-quinone), recently related with the dead of coho salmon, and hexamethoxymethylmelamine (HMMM), among others, were also detected. This is the first study in which the bioaccesibility from real crumb rubber samples of 15 out of the 16 PAHs considered as priority pollutants by the United States Environmental Protection Agency (EPA) and the presence of 6PPD-quinone and HMMM in the bioaccessible fractions is reported.


Assuntos
Benzoquinonas , Carcinógenos , Exposição Ambiental , Futebol Americano , Fenilenodiaminas , Hidrocarbonetos Policíclicos Aromáticos , Borracha , Triazinas , Criança , Humanos , Carcinógenos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Borracha/química , Fenilenodiaminas/análise , Benzoquinonas/análise , Triazinas/análise , Líquidos Corporais
8.
Environ Sci Pollut Res Int ; 30(1): 1871-1888, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35925464

RESUMO

The development of analytical methodologies to monitor different antibiotic families in water and the implementation of alternatives for their efficient elimination are a great challenge. The aim of this research was to develop a method based on solid-phase extraction followed by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry to analyse multi-class antibiotics, including macrolides, cephalosporins, fluoroquinolones, sulfonamides and diaminopyrimidines, in waters. Several parameters affecting the extraction such as the sample pH, type of sorbent and cartridge, elution volume and breakthrough volume were optimized. The method was validated in real samples, and matrix effect was assessed, demonstrating that the use of isotopically labelled surrogate compounds was mandatory to avoid standard addition calibration for each individual samples. Urban and hospital wastewater samples, as well as natural waters, were analysed, confirming the presence of 12 of the 14 target compounds at concentrations up to 3.5 µg L-1. Non-target analysis based on data-independent workflow was also performed, enabling the identification of 94 pollutants. Preliminary photodegradation experiments were also assessed, revealing the total removal of many target compounds after the first 5-10 min of UVC irradiation. In addition, 20 by-products formed after photolysis could be identified using a non-target approach.


Assuntos
Poluentes Químicos da Água , Água , Humanos , Água/química , Fotólise , Espectrometria de Massas em Tandem/métodos , Antibacterianos/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise
9.
J Agric Food Chem ; 70(41): 13118-13131, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36194443

RESUMO

Fungicide resistance is a major concern in modern agriculture; therefore, there is a pressing demand to develop new, greener chemicals. Chitin is a major component of the fungal cell wall and a well-known elicitor of plant immunity. To overcome chitin recognition, fungal pathogens developed different strategies, with chitin deacetylase (CDA) activity being the most conserved. This enzyme is responsible for hydrolyzing the N-acetamido group in N-acetylglucosamine units of chitin to convert it to chitosan, a compound that can no longer be recognized by the plant. In previous works, we observed that treatments with CDA inhibitors, such as carboxylic acids, reduced the symptoms of cucurbit powdery mildew and induced rapid activation of chitin-triggered immunity, indicating that CDA could be an interesting target for fungicide development. In this work, we developed an in silico strategy based on QSAR (quantitative structure-activity relationship) and molecular topology (MT) to discover new, specific, and potent CAD inhibitors. Starting with the chemical structures of few carboxylic acids, with and without disease control activity, three predictive equations based on the MT paradigm were developed to identify a group of potential molecules. Their fungicidal activity was experimentally tested, and their specificity as CDA inhibitors was studied for the three best candidates by molecular docking simulations. To our knowledge, this is the first time that MT has been used for the identification of potential CDA inhibitors to be used against resistant powdery mildew strains. In this sense, we consider of special interest the discovery of molecules capable of stimulating the immune system of plants by triggering a defensive response against fungal species that are highly resistant to fungicides such as powdery mildew.


Assuntos
Quitosana , Fungicidas Industriais , Doenças das Plantas/microbiologia , Fungicidas Industriais/farmacologia , Acetilglucosamina , Simulação de Acoplamento Molecular , Quitina/farmacologia , Agricultura , Ácidos Carboxílicos
10.
Biomedicines ; 10(6)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35740363

RESUMO

During an emergency, such as a pandemic in which time and resources are extremely scarce, it is important to find effective and rapid solutions when searching for possible treatments. One possibility in this regard is the repurposing of available "on the market" drugs. This is a proof of the concept study showing the potential of a collaboration between two research groups, engaged in computer-aided drug design and control of viral infections, for the development of early strategies to combat future pandemics. We describe a QSAR (quantitative structure activity relationship) based repurposing study on molecular topology and molecular docking for identifying inhibitors of the main protease (Mpro) of SARS-CoV-2, the causative agent of COVID-19. The aim of this computational strategy was to create an agile, rapid, and efficient way to enable the selection of molecules capable of inhibiting SARS-CoV-2 protease. Molecules selected through in silico method were tested in vitro using human coronavirus 229E as a surrogate for SARS-CoV-2. Three strategies were used to screen the antiviral activity of these molecules against human coronavirus 229E in cell cultures, e.g., pre-treatment, co-treatment, and post-treatment. We found >99% of virus inhibition during pre-treatment and co-treatment and 90−99% inhibition when the molecules were applied post-treatment (after infection with the virus). From all tested compounds, Molport-046-067-769 and Molport-046-568-802 are here reported for the first time as potential anti-SARS-CoV-2 compounds.

11.
Anal Chim Acta ; 1203: 339650, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35361419

RESUMO

Because of the coronavirus pandemic, hydroalcoholic gels have become essential products to prevent the spread of COVID-19. This research aims to develop a simple, fast and sustainable microextraction methodology followed by gas chromatography tandem mass spectrometry (GC-MS/MS) to analyze simultaneously 60 personal care products (PCPs) including fragrances allergens, synthetic musks, preservatives and plasticizers in hand sanitizers. Micro-matrix-solid-phase dispersion (µMSPD) and solid-phase microextraction (SPME) were compared with the aim of obtaining high sensitivity and sample throughput. SPME demonstrated higher efficiency being selected as sample treatment. Different dilutions of the sample in ultrapure water were assessed to achieve high sensitivity but, at the same time, to avoid or minimize matrix effect. The most critical parameters affecting SPME (fibre coating, extraction mode and temperature) were optimized by design of experiments (DOE). The method was successfully validated in terms of linearity, precision and accuracy, obtaining recovery values between 80 and 112% for most compounds with relative standard deviation (RSD) values lower than 10%. External calibration using standards prepared in ultrapure water demonstrated suitability due to the absence of matrix effect. Finally, the simple, fast and high throughput method was applied to the analysis of real hydroalcoholic gel samples. Among the 60 target compounds, 39 of them were found, highlighting the high number of fragrance allergens, at concentrations ranging between 0.01 and 217 µg g-1. Most of the samples were not correctly labelled attending cosmetic Regulation (EU) No 1223/2009, and none of them followed the World Health Organization (WHO) recommendation for hand sanitizers formulation.


Assuntos
COVID-19 , Cosméticos , Higienizadores de Mão , Cosméticos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Géis , Higienizadores de Mão/análise , Humanos , Pandemias , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
12.
Mikrochim Acta ; 189(4): 164, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35352182

RESUMO

Cellulose acetate fibers were modified with a gelatin cryogel adsorbent incorporating an iron-carboxylate metal-organic framework and hypercrosslinked polymer composite. The hybrid adsorption materials facilitated the adsorption ability toward polycyclic aromatic hydrocarbons and were entrapped into gelatin cryogel to be hierarchically coated on cellulose acetate fibers which helped to reduce the clogging problem of packed adsorbent. The composite adsorbent was employed as the solid phase of an in-syringe miniaturized solid-phase extraction system. The adsorbent was packed into the needle hub of a disposable syringe and used to extract and preconcentrate polycyclic aromatic hydrocarbons in water sample. The fabricated porous composite adsorbent was characterized and extraction conditions were optimized to achieve the best extraction performance. High-performance liquid chromatography was employed to separate and quantify extracted PAHs. The developed analysis method provided a linear range of 0.020-50 µg L-1 for phenanthrene and benzo(b)fluoranthene, 0.010-50 µg L-1 for pyrene, 0.0020-50 µg L-1 for benzo(a)anthracene, and 0.0050-50 µg L-1 for benzo(a)pyrene and dibenzo(a,h)anthracene. The limits of detection ranged from 0.5 to 5.0 ng L-1. Recoveries ranged from 89 to 98% with RSDs below 7%. The good stability of the adsorbent allowed up to 21 cycles of efficient extraction and desorption.


Assuntos
Estruturas Metalorgânicas , Hidrocarbonetos Policíclicos Aromáticos , Celulose/análogos & derivados , Criogéis , Gelatina , Ferro , Hidrocarbonetos Policíclicos Aromáticos/análise , Polímeros , Extração em Fase Sólida/métodos , Seringas
13.
J Chromatogr A ; 1668: 462911, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35248870

RESUMO

A fast, efficient, and simple air sampling methodology was developed to study a high number of volatile and semivolatile organic compounds in air above tire rubber materials and surfaces made of recycled tire rubber. The proposed method, based on active sampling (solid-phase extraction, SPE) using a small quantity of sorbent material (25 mg) followed by solid-phase microextraction (SPME) and gas chromatography-tandem mass spectrometry analysis, was developed with the aim of determining 40 organics substances including polycyclic aromatic hydrocarbons (PAHs), plasticizers, antioxidants, and vulcanization agents. An experimental design was carried out to study the influence of main factors such as type of SPME fibre, solvent addition, headspace volume, stirring, as well as the factor interactions. Method performance showed good linearity in a broad concentration range (0.05 to 200 ng m-3, for most compounds), with coefficients of determination (R2) higher than 0.9900. Whole method precision (≤ 16 %) and accuracy were also satisfactory, obtaining quantitative recoveries (mean values between 80 and 110 % in most cases). Limits of detection and quantification have also been calculated, yielding values of sub ng m-3 for most compounds. The validated method was applied to outdoor and indoor air environments including playgrounds, football pitches and warehouses showing the presence of most target compounds in the samples achieving high levels for some PAHs (concentrations up to 51 ng m-3), benzothiazole (BTZ), diisobutyl- dibutyl- and di-(2-ethylhexyl)- phthalate, among others, reaching concentrations up to hundreds of ng m-3 (BTZ). This is the first time that the combination of techniques SPE and SPME is applied for these families of chemicals, and it is also the first time that this approach is proposed for the simultaneous multiclass compound extraction of substances of different chemical families. The whole sampling and extraction procedure is performed in a short period of time (61 min) allowing high throughput. The elimination of the use of organic solvents and waste generation by using only 25 mg of sorbent and a SPME fibre than are both reused makes the method sustainable and in consonance with the principles of the green chemistry. The method can be implemented in any routine lab and easily automated using a SPME autosampler.


Assuntos
Borracha , Microextração em Fase Sólida , Cromatografia Gasosa-Espectrometria de Massas/métodos , Substâncias Perigosas/análise , Borracha/química , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem
14.
Pharmaceuticals (Basel) ; 15(1)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35056151

RESUMO

Even if amyotrophic lateral sclerosis is still considered an orphan disease to date, its prevalence among the population is growing fast. Despite the efforts made by researchers and pharmaceutical companies, the cryptic information related to the biological and physiological onset mechanisms, as well as the complexity in identifying specific pharmacological targets, make it almost impossible to find effective treatments. Furthermore, because of complex ethical and economic aspects, it is usually hard to find all the necessary resources when searching for drugs for new orphan diseases. In this context, computational methods, based either on receptors or ligands, share the capability to improve the success rate when searching and selecting potential candidates for further experimentation and, consequently, reduce the number of resources and time taken when delivering a new drug to the market. In the present work, a computational strategy based on Molecular Topology, a mathematical paradigm capable of relating the chemical structure of a molecule to a specific biological or pharmacological property by means of numbers, is presented. The result was the creation of a reliable and accessible tool to help during the early in silico stages in the identification and repositioning of potential hits for ALS treatment, which can also apply to other orphan diseases. Considering that further computational and experimental results will be required for the final identification of viable hits, three linear discriminant equations combined with molecular docking simulations on specific proteins involved in ALS are reported, along with virtual screening of the Drugbank database as a practical example. In this particular case, as reported, a clinical trial has been already started for one of the drugs proposed in the present study.

15.
Chemosphere ; 293: 133552, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35007608

RESUMO

Although there are several works in the literature that study the presence of pharmaceuticals and personal care products (PPCPs) in surface waters, the vast majority focus their attention on pharmaceuticals and little information is found about personal care products (PCPs). Therefore, this study focused, for the first time, on the monitoring of five classes of PCPs - fragrance allergens, synthetic musks, phthalates, antioxidants, and ultraviolet-filters - in the surface water of four small-size typically pollution-impacted Portuguese rivers (Ave, Leça, Antuã and Cértima). A solid-phase microextraction (SPME) followed by gas chromatography - tandem mass spectrometry (GC-MS/MS) protocol was employed to analyse surface water samples collected in two seasonal campaigns - summer and winter (34 samples per season). A total of 22 out of 37 target PCPs were detected concomitantly at least once in one sampling point, being the most frequently detected α-isomethyl ionone, galaxolide, tonalide and cashmeran. The highest concentrations were confirmed for diethylhexyl phthalate (610.6 ng L-1), galaxolide (379.2 ng L-1), geraniol (290.9 ng L-1), linalool (271.2 ng L-1), benzophenone-3 (254.1 ng L-1) and citronellol (200.2 ng L-1). Leça River, traversing the more densely urban and industrialized area, had the highest levels of contaminants, which were also found in the sampling points located downstream of wastewater treatment plants discharge points. In general, higher levels were detected in summer, when the river flows are lower. Hazard quotients were determined and octocrylene, tonalide, and geraniol presented values above 1 in some sampling sites, which may indicate an ecotoxicological risk to the aquatic environment. The results presented suggest that these three PCPs should be included as priority pollutants in environmental monitoring schemes in surface waters, due to their high detection, persistence, and potential adverse effects.


Assuntos
Cosméticos , Poluentes Químicos da Água , Cosméticos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Portugal , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise
16.
Artigo em Inglês | MEDLINE | ID: mdl-36644410

RESUMO

Background: Although artificial turf fields are utilized widely around the world, sufficient research has not yet been conducted to assess the potential human and environmental health risks posed by the chemicals contained in the fields' fibers, backing, and often-used crumb rubber infill. Consequently, there is wide variation in governmental policies. Objective: Review the notable policies concerning artificial turf and crumb rubber infill in the European Union, United Kingdom, United States of America, Canada, China, Qatar, and the Global Stockholm Convention of the United Nations. Methods: Information was collected that included published papers, technical and policy reports, and grey literature. These were then analyzed by a collaborative group familiar with the environmental policies in their respective countries to extract the pertinent legislative or regulatory information. The group members were primarily identified through their involvement in publications pertinent to artificial turf and crumb rubber infill health research and included environmental health professors, active researchers, and governmental agency officials. Most information on direct policies was taken directly from reports provided to the public by various governmental agencies responsible for their countries' regulations, often available within the respective agency's online archives. Results: There are significant differences in the regulatory approaches adopted by the investigated countries with regards to artificial turf and its crumb rubber infill. Some regions, such as the European Union, have taken substantial steps to limit the fields' chemical components to which the public and environment are exposed. Other regions and countries have done far less to address the issue. Most policies relate directly to (i) the fields themselves, (ii) the microplastic components of crumb rubber infill, or (iii) the concentrations of harmful polycyclic aromatic hydrocarbons (PAHs), perfluoroalkyl and polyfluoroalkyl substances (PFAS), and heavy metals. Conclusion: While nearly every country acknowledges the potential health risks posed by heavy metals, microplastics, PAHs, and PFAS chemicals, very few have actually implemented artificial turf and crumb rubber infill regulations and/or established adequate surveillance measures to protect those regularly exposed to the fields.

17.
Sci Total Environ ; 812: 152542, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34952075

RESUMO

Social and environmental concern about the use of crumb rubber from end-of-life car tires in the construction of different sport and recreational facilities is increasing due to the presence of hazardous compounds. The aim of this research was the assessment of 42 organic chemicals, including polycyclic aromatic hydrocarbons (PAHs), phthalates, adipates, antioxidants and vulcanisation agents in a large number of infill samples (91) from synthetic turf football pitches of diverse characteristics and geographical origin. Samples were taken worldwide, in 17 countries on 4 continents, to show the global dimension of this problem. Ultrasound assisted extraction was employed to extract the target compounds, followed by gas chromatography coupled to tandem-mass spectrometry (UAE-GC-MS/MS). Seventy-eight crumb rubber samples as well as thirteen samples of alternatives materials, such as cork granulates, thermoplastic elastomers and coconut fibre, were analyzed. The results highlight the presence of all target PAH in most rubber samples at concentrations up to µg g-1, including the eight ECHA (European Chemicals Agency) PAHs considered as carcinogenic, and anthracene (ANC), pyrene (PYR) and benzo[ghi]perylene (B[ghi]P), catalogued as substances of very high concern (SVHC). Endocrine disruptors such as some plasticizers (mainly phthalates), and other compounds like benzothiazole (BTZ) and 2-mercaptobenzothiazole (MBTZ) were found reaching the mg g-1 level. This confirms the presence of the hazardous substances in the recycled crumb rubber samples collected all around the world. Three crumb rubber samples exceeded the limit of 20 µg g-1 for the sum of the eight ECHA PAHs. Regarding the chemical composition of other infill alternatives, cork appears to be adequate, while the thermoplastic elastomers contained high levels of some plasticizers. In addition, the plastic infill as well as the crumb rubber both are microplastics. Microplastics are considered contaminants of emerging concern since they do not biodegrade and remain in the environment for a long time.


Assuntos
Futebol Americano , Hidrocarbonetos Policíclicos Aromáticos , Cromatografia Gasosa-Espectrometria de Massas , Plásticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Borracha , Espectrometria de Massas em Tandem
18.
Foods ; 10(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34828899

RESUMO

Honey is a natural product well known for its beneficial properties. It contains phytochemicals, a wide class of nutraceuticals found in plants, including compounds with highly demonstrated antimicrobial and antioxidant capacities as phenolic compounds and flavonoids. The main goal of this work is the development of a miniaturized and environmentally friendly methodology to obtain the phenolic profile of Galician honeys (Northwest Spain) from different varieties such as honeydew, chestnut, eucalyptus, heather, blackberry and multi-floral. The total phenolic content (TPC) and antioxidant activity (AA) were also evaluated. As regards sample preparation, miniaturized vortex (VE) and ultrasound assisted extraction (UAE) employing aqueous-based solvents were performed. Individual quantification of 41 target phenolic compounds was carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results revealed the presence of 25 phenolic compounds in the 91 analyzed samples, reaching concentrations up to 252 µg g-1. Statistical tools such as analysis of variance (ANOVA) and principal component analysis (PCA) were employed to obtain models that allowed classifying the different honeys according to their botanical origin. Obtained results, based on TPC, AA and ∑phenolic compounds showed that significant differences appeared depending on the honey variety, being several of the identified phenol compounds being responsible of the main differentiation.

19.
Molecules ; 26(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34684732

RESUMO

Seventeen fungicides were determined in different matrices from vineyard areas, including vine leaves, soils, grapes and water, using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). For leaf analysis, ultrasound-assisted extraction (UAE) was performed evaluating different solvents. UAE was compared with other extraction techniques such as vortex extraction (VE) and matrix solid-phase dispersion (MSPD). The performance of the UAE method was demonstrated on vine leaf samples and on other types of samples such as tea leaves, underlining its general suitability for leaf crops. As regards other matrices, soils were analyzed by UAE and microwave-assisted extraction (MAE), grapes by UAE and waters by SPE using cork as the sorbent. The proposed method was applied to 17 grape leaf samples in which 14 of the target fungicides were detected at concentrations up to 1000 µg g-1. Furthermore, the diffusion and transport of fungicides was demonstrated not only in crops but also in environmental matrices.


Assuntos
Monitoramento Ambiental/métodos , Fazendas/tendências , Fungicidas Industriais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Folhas de Planta/química , Solo/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Vitis/química
20.
J Chromatogr A ; 1655: 462497, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34487884

RESUMO

A dumbbell-shaped stir bar adsorbent of MIL-101 entrapped in PVA cryogel coated with poly(3,4-ethylenedioxythiophene) was fabricated to extract synthetic phenolic antioxidants in foodstuffs. The interconnected porous of cryogel allowed the entrapment of MIL-101 and enhanced the surface areas of poly(3,4-ethylenedioxythiophene) coating which facilitated multiple adsorptions. The fabricated adsorbent was characterized and measured the adsorption capacities for synthetic phenolic antioxidants. Extraction efficiency was optimized by evaluating the effect of adsorbent compositions, extraction time, stirring speed, sample pH, desorption conditions, sample volume and ionic strength. The analysis of extracted synthetic phenolic antioxidants was carried out using high performance liquid chromatography. The developed analysis method provided a wide linear range of 0.20 - 200 µg kg-1 for butylated hydroxyanisole and 0.50 - 200 µg kg-1 for tert­butylhydroquinone and butylated hydroxytoluene. The limits of detection were between 0.05 and 0.15 µg kg-1. The developed stir bar adsorbent was utilized to extract these three synthetic phenolic antioxidants from juice, milk, infant formula and coffee creamer. Recoveries ranged from 87 to 101% with RSDs below 7%. The developed composite stir bar adsorbent was convenient to use, and good physical and chemical stability allowed efficient extraction for 12 extraction cycles.


Assuntos
Estruturas Metalorgânicas , Antioxidantes , Compostos Bicíclicos Heterocíclicos com Pontes , Cromatografia Líquida de Alta Pressão , Criogéis , Humanos , Limite de Detecção , Polímeros , Porosidade , Reprodutibilidade dos Testes
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