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1.
J Chromatogr A ; 1566: 13-22, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29945788

RESUMO

Polycyclic Aromatic Hydrocarbons (PAHs) have been detected in rubber and plastic components of a number of consumer products such as toys, tools for domestic use, sports equipment, and footwear, with carbon black and extender oils having been identified as principal sources. In response to these findings, the European Union Regulation (EU) No. 1272/2013 was adopted in December 2013, amending entry 50 in Annex XVII to the Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH) directive establishing a restriction on the content of eight individual carcinogenic PAHs in plastic and rubber parts of products supplied to the public. This work proposes a simple, relatively fast, and cost effective method for determining the concentrations of each of these eight carcinogenic PAHs for compliance testing. Existing methodologies were taken as a starting point, improving in particular the extraction and the clean-up procedures. Randall hot extraction and ultrasonic extraction were compared with regard to their extraction efficiency. Randall hot extraction proved to be more efficient (10-40%, depending on PAH). Sample extract clean-up performance was qualitatively assessed for silica-packed columns and molecularly imprinted polymers (MIPs) solid phase extraction (SPE) cartridges. The use of highly selective MIP-SPE cartridges removed most of the undesired contaminants, highlighting their superiority with regard to traditional, silica-based purification methodologies. The introduction of Randall-hot extraction for sample extraction and MIP-based solid phase extraction cartridges for selective clean-up represents a novel advance compared with previously reported methods in this field. In combination with gas chromatography-mass spectrometry (GC-MS) analyses in selected ion mode, the method was found to be excellent in terms of extraction efficiency, extract purity, and speed.


Assuntos
Técnicas de Química Analítica/métodos , Plásticos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Borracha/química , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Extração em Fase Sólida
2.
Curr Pharm Biotechnol ; 19(2): 91-98, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29792142

RESUMO

BACKGROUND: The emergence of psychoactive designer drugs has significantly increased over the last few years. Customs officials are responsible for the control of products entering the European Union (EU) market. This control applies to chemicals in general, pharmaceutical products and medicines. Numerous products imported from non-EU countries, often declared as 'bath salts' or 'fertilizers', contain new psychoactive substance (NPS). REVIEW: These are not necessarily controlled under international law, but may be subject to monitoring in agreement with EU legislation. This situation imposes substantial challenges, for example, for the maintenance of spectral libraries used for their detection by designated laboratories. The chemical identification of new substances, with the use of powerful instrumentation, and the time needed for detailed analysis and interpretation of the results, demands considerable commitment. The EU Joint Research Centre endeavors to provide scientific support to EU Customs laboratories to facilitate rapid identification and characterisation of seized samples. In addition to analysing known NPS, several new chemical entities have also been identified. Frequently, these belong to NPS classes already notified to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) by the European Early- Warning System (EWS). CONCLUSION: The aim of this paper is to discuss the implementation of workflow mechanisms that are in place in order to facilitate the monitoring, communication and management of analytical data. The rapid dissemination of this information between control authorities strives to help protect EU citizens against the health risks posed by harmful substances.


Assuntos
Pesquisa Biomédica/métodos , União Europeia , Colaboração Intersetorial , Psicotrópicos/análise , Pesquisa Biomédica/tendências , Humanos , Psicotrópicos/química , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle
3.
Forensic Sci Int ; 265: 107-15, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26874735

RESUMO

New psychoactive substances (NPS) are synthesized compounds that are not usually covered by European and/or international laws. With a slight alteration in the chemical structure of existing illegal substances registered in the European Union (EU), these NPS circumvent existing controls and are thus referred to as "legal highs". They are becoming increasingly available and can easily be purchased through both the internet and other means (smart shops). Thus, it is essential that the identification of NPS keeps up with this rapidly evolving market. In this case study, the Belgian Customs authorities apprehended a parcel, originating from China, containing two samples, declared as being "white pigments". For routine identification, the Belgian Customs Laboratory first analysed both samples by gas-chromatography mass-spectrometry and Fourier-Transform Infrared spectroscopy. The information obtained by these techniques is essential and can give an indication of the chemical structure of an unknown substance but not the complete identification of its structure. To bridge this gap, scientific and technical support is ensured by the Joint Research Centre (JRC) to the European Commission Directorate General for Taxation and Customs Unions (DG TAXUD) and the Customs Laboratory European Network (CLEN) through an Administrative Arrangement for fast recognition of NPS and identification of unknown chemicals. The samples were sent to the JRC for a complete characterization using advanced techniques and chemoinformatic tools. The aim of this study was also to encourage the development of a science-based policy driven approach on NPS. These samples were fully characterized and identified as 5F-AMB and PX-3 using (1)H and (13)C nuclear magnetic resonance (NMR), high-resolution tandem mass-spectrometry (HR-MS/MS) and Raman spectroscopy. A chemoinformatic platform was used to manage, unify analytical data from multiple techniques and instruments, and combine it with chemical and structural information.


Assuntos
Psicotrópicos/análise , Detecção do Abuso de Substâncias/métodos , Bélgica , Crime/legislação & jurisprudência , Toxicologia Forense , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
4.
Environ Int ; 35(8): 1188-95, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19729200

RESUMO

The presence of selected volatile organic compounds (VOCs) including aromatic, aliphatic compounds and low molecular weight carbonyls, and a target set of phthalates were investigated in the interior of 23 used private cars during the summer and winter. VOC concentrations often exceeded levels typically found in residential indoor air, e.g. benzene concentrations reached values of up to 149.1 microg m(-3). Overall concentrations were 40% higher in summer, with temperatures inside the cars reaching up to 70 degrees C. The most frequently detected phthalates were di-n-butyl-phthalate and bis-(2-ethylhexyl) phthalate in concentrations ranging from 196 to 3656 ng m(-3).


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Automóveis/estatística & dados numéricos , Ácidos Ftálicos/análise , Compostos Orgânicos Voláteis/análise , Benzeno/análise , Dibutilftalato/análise , Monitoramento Ambiental , Plastificantes/análise , Estações do Ano , Temperatura , Emissões de Veículos/análise
5.
Anal Bioanal Chem ; 392(1-2): 313-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18584154

RESUMO

Near-infrared microscopy (NIRM) has been proved to be a powerful tool for the detection of banned meat and bone meal (MBM) in feed. The identification of MBM traces and its ability to differentiate animal from vegetable feed ingredients is based on the evaluation of near-infrared spectra obtained from individual particles present in the sample. This evaluation is supported by appropriate decision rules for the absorbances at specific wavelengths. Here we show that the method and the corresponding decision rules can be successfully transferred from the laboratory which constructed the decision rules to two independent laboratories that were not involved in the calibration process of the method. The analytical results from blind feed samples containing MBM (positive samples) and feed samples without MBM (negative samples) revealed a very good agreement between the three laboratories, thus demonstrating the transferability of the method.


Assuntos
Ração Animal/análise , Carne/análise , Microscopia/métodos , Minerais/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ração Animal/normas , Produtos Biológicos/análise
6.
Environ Sci Pollut Res Int ; 15(5): 417-30, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18491156

RESUMO

BACKGROUND, AIM AND SCOPE: All across Europe, people live and work in indoor environments. On average, people spend around 90% of their time indoors (homes, workplaces, cars and public transport means, etc.) and are exposed to a complex mixture of pollutants at concentration levels that are often several times higher than outdoors. These pollutants are emitted by different sources indoors and outdoors and include volatile organic compounds (VOCs), carbonyls (aldehydes and ketones) and other chemical substances often adsorbed on particles. Moreover, legal obligations opposed by legislations, such as the European Union's General Product Safety Directive (GPSD) and Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), increasingly require detailed understanding of where and how chemical substances are used throughout their life-cycle and require better characterisation of their emissions and exposure. This information is essential to be able to control emissions from sources aiming at a reduction of adverse health effects. Scientifically sound human risk assessment procedures based on qualitative and quantitative human exposure information allows a better characterisation of population exposures to chemical substances. In this context, the current paper compares inhalation exposures to three health-based EU priority substances, i.e. benzene, formaldehyde and acetaldehyde. MATERIALS AND METHODS: Distributions of urban population inhalation exposures, indoor and outdoor concentrations were created on the basis of measured AIRMEX data in 12 European cities and compared to results from existing European population exposure studies published within the scientific literature. By pooling all EU city personal exposure, indoor and outdoor concentration means, representative EU city cumulative frequency distributions were created. Population exposures were modelled with a microenvironment model using the time spent and concentrations in four microenvironments, i.e. indoors at home and at work, outdoors at work and in transit, as input parameters. Pooled EU city inhalation exposures were compared to modelled population exposures. The contributions of these microenvironments to the total daily inhalation exposure of formaldehyde, benzene and acetaldehyde were estimated. Inhalation exposures were compared to the EU annual ambient benzene air quality guideline (5 microg/m3-to be met by 2010) and the recommended (based on the INDEX project) 30-min average formaldehyde limit value (30 microg/m3). RESULTS: Indoor inhalation exposure contributions are much higher compared to the outdoor or in-transit microenvironment contributions, accounting for almost 99% in the case of formaldehyde. The highest in-transit exposure contribution was found for benzene; 29.4% of the total inhalation exposure contribution. Comparing the pooled AIRMEX EU city inhalation exposures with the modelled exposures, benzene, formaldehyde and acetaldehyde exposures are 5.1, 17.3 and 11.8 microg/m3 vs. 5.1, 20.1 and 10.2 microg/m3, respectively. Together with the fact that a dominating fraction of time is spent indoors (>90%), the total inhalation exposure is mostly driven by the time spent indoors. DISCUSSION: The approach used in this paper faced three challenges concerning exposure and time-activity data, comparability and scarce or missing in-transit data inducing careful interpretation of the results. The results obtained by AIRMEX underline that many European urban populations are still exposed to elevated levels of benzene and formaldehyde in the inhaled air. It is still likely that the annual ambient benzene air quality guideline of 5 microg/m3 in the EU and recommended formaldehyde 30-min average limit value of 30 microg/m3 are exceeded by a substantial part of populations living in urban areas. Considering multimedia and multi-pathway exposure to acetaldehyde, the biggest exposure contribution was found to be related to dietary behaviour rather than to inhalation. CONCLUSIONS: In the present study, inhalation exposures of urban populations were assessed on the basis of novel and existing exposure data. The indoor residential microenvironment contributed most to the total daily urban population inhalation exposure. The results presented in this paper suggest that a significant part of the populations living in European cities exceed the annual ambient benzene air quality guideline of 5 microg/m3 in the EU and recommended (INDEX project) formaldehyde 30-min average limit value of 30 microg/m3. RECOMMENDATIONS AND PERSPECTIVES: To reduce exposures and consequent health effects, adequate measures must be taken to diminish emissions from sources such as materials and products that especially emit benzene and formaldehyde in indoor air. In parallel, measures can be taken aiming at reducing the outdoor pollution contribution indoors. Besides emission reduction, mechanisms to effectively monitor and manage the indoor air quality should be established. These mechanisms could be developed by setting up appropriate EU indoor air guidelines.


Assuntos
Acetaldeído/análise , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Benzeno/análise , Formaldeído/análise , Exposição por Inalação/análise , Simulação por Computador , União Europeia , Humanos , Modelos Químicos , População Urbana
7.
Rapid Commun Mass Spectrom ; 22(4): 471-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18205250

RESUMO

2,3-Dimethyl-2,3-diisobutyl succinonitrile was identified as the main volatile organic compound (>90%) emitted from laser printers during the printing process. Experiments were carried out in a large environmental chamber of 30 m3, where the printers were placed and working simulating 'real office setting' conditions. Air samples were taken on Tenax TA adsorbent cartridges in the vicinity of the printers and further analyzed by thermal desorption gas chromatography/mass spectrometry (TDGC/MS). The structure of the compound has been determined and is presented in this study. Additional data obtained by nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy, and liquid chromatography/tandem mass spectrometry (LC/MS/MS) support the proposed structure, with no reported CAS number, as 2,3-dimethyl-2,3-diisobutyl succinonitrile. It is a byproduct of the thermal decomposition of 2,2'-azobis(2,4-dimethyl valeronitrile), a commercially available free radical polymerization initiator used in polymerization processes during the manufacture of the toners. By means of head-space GC/MS, 15 toners used in black & white and colour printers have been investigated. Six of them contained 2,3-dimethyl-2,3-diisobutyl succinonitrile, which has also been detected in the respective processed paper.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Periféricos de Computador , Monitoramento Ambiental/métodos , Tinta , Lasers , Nitrilas/análise , Impressão/instrumentação , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Anal Bioanal Chem ; 382(4): 1073-83, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15933852

RESUMO

The objective of the reported study was to assess the abilities of various methods to differentiate the sources of fats used in feedstuff formulations. The main target was the identification of tallow (ruminant fat) and its differentiation from non-ruminant fats. Four different techniques were compared in terms of their suitability for enforcing existing and upcoming legislation on animal by-products: (1) Fourier transform infrared spectroscopy (FT-IR) applied to fat samples, (2) gas chromatography coupled with mass spectrometry (GC-MS) to determine fatty acid profiles, (3) immunoassays focusing on the protein fraction included in the fat, and (4) polymerase chain reaction (PCR) for the detection of bovine-specific DNA. Samples of the different fats and oils as well as mixtures of these fats were probed using these analytical methods. FT-IR and GC-MS differentiated pure fat samples quite well but showed limited ability to identify the animal species or even the animal class the fat(s) belonged to; no single compound or spectral signal that could permit species identification could be found. However, immunoassays and PCR were both able to identify the species or groups of species that the fats originated from, and they were the only techniques able to identify low concentrations of tallow in a mixture of fats prepared by the rendering industry, even when the samples had been sterilised at temperatures >133 degrees C. Fats used in animal nutrition come mainly from the rendering industry, thereby confirming the suitability of PCR and immunoassays for their identification. However, neither of these latter techniques was able to detect "premier jus" tallow, representing the highest quality standard of fat with extremely low protein concentration.


Assuntos
Gorduras/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Animais , Bovinos , Galinhas , Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , DNA/genética , Peixes , Cavalos , Imunoensaio/métodos , Espectrometria de Massas/métodos , Análise Multivariada , Coelhos , Sensibilidade e Especificidade , Ovinos
9.
Epidemiol Prev ; 29(5-6 Suppl): 17-21, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16646255

RESUMO

Benzene and formaldehyde are among the principal components in the air of various indoor occupational and non-occupational environments. Both compounds are toxicologically relevant for humans as recognized carcinogens. In order to evaluate the total exposure and to assess the possible health risk caused by benzene and formaldehyde for different population groups at European level, the JRC Institute for Health and Consumer Protection in Ispra launched the AIRMEX (IndoorAir Monitoring and ExposureAssessment Study) project in October 2003. It aims at identifying and quantifying the main indoor pollutants particularly in kindergartens, schools and public buildings. It also intends to evaluate the overall exposure of people working and occupying these areas. Measuring campaigns were carried out in pre-selected indoor environments in various European cities (Catania, Athens, Arnhem, Nijmegen, Brussels, Thessaloniki). Preliminary results clearly indicate that indoor air concentrations for volatile compounds (VOC) including benzene are higher than/or similar to those found outdoors, ranging from a few micrograms (about 8 microg/m3) to 281 microg/m3. Outdoor concentrations vary from 7 to 153 microg/m3. Personal exposure concentrations are generally higher than the indoor/outdoor concentrations. In most cases they are twice as high as indoor concentrations (or even higher) and significantly higher than outdoor concentrations. Air concentrations of aldehydes inside buildings/kindergartens were up to 7-8 times higher than outside. This mostly concerns formaldehyde, and it seems that strong indoor sources exist which clearly determine the indoor air concentrations. Formaldehyde concentrations in public buildings and offices vary from 3 to 30 microg/m3, and those in kindergartens vary from 6 to 11 microg/m3 (Arnhem/Nijmegen). The highest values for formaldehyde, up to 29,9 microg/m3, were found in Catania, Athens and Thessaloniki.


Assuntos
Poluição do Ar/análise , Benzeno/análise , Exposição Ambiental/análise , Formaldeído/análise , Europa (Continente) , Humanos
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