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1.
Environ Res ; 218: 114865, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36435495

RESUMO

OBJECTIVES: We show that participatory research approaches can be a useful tool across disciplines and data collection methods to explore the socio-exposome near one of the largest industrial harbors in Europe. We analyzed resident involvement in each project and their capacity to affect structural changes. METHODS: Longitudinal participatory environmental monitoring studies on lichens, petunias, aquatic systems and groundwater were conducted under the program VOCE (Volunteers for the Citizens' Observation of the Environment), which mobilized nearly 100 volunteers to collect and report data. A community-based participatory health survey, Fos EPSEAL was also carried out during the same period. We describe citizens' involvement in each study following Davis and Ramirez-Andreotta's (2021) 'best practice' grid. We also use residents' insights to refine understanding of the socio-exposome. RESULTS: The region is significantly impacted by industrial pollution and fenceline communities are disproportionately exposed. The community-based participatory health survey documented negative health outcomes among the residents, including a higher prevalence of chronic symptoms and diabetes (e.g., 11.9%) in the Fos-Berre Lagoon region than in other communities. This methodology shows the benefits of the co-production of knowledge in environmental health: not only does it enable epistemological transformations favorable to the vulnerable population, but it also triggered public action (i.e., media and public authorities' attention leading to official expertise reports, filing of collective complaints before the courts). CONCLUSION: This body of multiple participatory research studies over time is a useful approach to better understand the socio-exposome and health issues in an industrial zone.


Assuntos
Expossoma , Humanos , Saúde Ambiental , Poluição Ambiental , Monitoramento Ambiental , Indústrias , Exposição Ambiental/análise
2.
Environ Sci Technol ; 56(3): 1522-1533, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35037465

RESUMO

Bromoform (CHBr3) belongs to very-short-lived substances (VSLSs), which are important precursors of reactive bromine species (BrOx) contributing to tropospheric and stratospheric chemistry. To date, most models calculating bromine product emissions to the atmosphere only consider the natural production of CHBr3 from marine organisms such as macroalgae and phytoplankton. However, CHBr3 has many other anthropogenic sources (coastal industrial sites, desalination and wastewater plants, ballast waters, and seawater toilets) that may drastically increase the amounts emitted in the atmosphere. Here, we report the levels of CHBr3 released in water and air (according to real-time and offline measurements by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS) and gas chromatography with electron capture detection (GC-ECD)) in a highly industrialized area where 3 million cubic meters of chlorinated seawater is released each day, which were measured during six field campaigns (at sea and on land) distributed over 3 years. The highest levels found during this survey (which were correlated to the physical-chemical characteristics of the water, meteorological and hydrological conditions, salinity, and temperature gradients along the water column) reached 34.6 µg L-1 in water (100-10 000 times higher than reported natural levels) and 3.9 ppbv in the air (100 times higher than the maximum reported value to date). These findings suggest the need to undertake sampling and analysis campaigns as close as possible to chlorinated discharges, as anthropogenic CHBr3 sources from industrial discharges may be a missing factor in global flux estimates or organic bromine to the atmosphere.


Assuntos
Bromo , Trialometanos , Cromatografia Gasosa-Espectrometria de Massas , Água
3.
J Environ Sci (China) ; 109: 193-205, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607668

RESUMO

The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency, in 3 sites of contrasted anthropic influence. The impact of the meteorological factors (temperature, relative humidity, rainfall, wind speed) was first estimated through principal component analysis, and then by stepwise multilinear regressions to include wind directions. The pollutants levels reflected the proximity of atmospheric emissions, in particular from a large industrial harbor. High humidity and mild temperatures, and in a lower extent low wind speed and rainfall, also favored higher concentration levels. The contributions of these meteorological aspects became minor when including wind direction, especially when approaching major emission sources. The bioaccumulation integration time towards meteorological variations was on a seasonal basis (1-2 months) but the wind direction and thus local emissions also relied on a longer time scale (12 months). This showed that the contribution of meteorological conditions may be prevalent in remote places, while secondary in polluted areas, and should be definitely taken into account regarding long-term lichen biomonitoring and inter-annual comparisons. In the same time, a quadruple sampling in each site revealed a high homogeneity among supporting tree species and topography. The resulting uncertainty, including sampling, preparation and analysis was below 30% when comfortable analytical conditions were achieved. Finally, the occurrence of unexpected events such as a major forest fire, permitted to evaluate that this type of short, although intense, events did not have a strong influence on PAH and metals bioaccumulation by lichen.


Assuntos
Poluentes Atmosféricos , Líquens , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Ascomicetos , Bioacumulação , Monitoramento Ambiental
4.
Sci Total Environ ; 955: 177286, 2024 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-39477126

RESUMO

The extensive use of pesticides combined with their persistence in the environment requires new methodologies to assess more effectively the population exposure to pesticides via air pollution. Biomonitoring pesticides with lichens has been poorly documented, although it represents a complementary approach to the usual active samplings, with an exposure to pesticides accumulated and integrated over several months. An optimized extraction procedure from the lichen Xanthoria parietina followed by a gas chromatographic-tandem mass spectrometric analysis is proposed here to quantify simultaneously 48 pesticides considered in France as priority active substances to monitor in the air. This method has been applied to lichen samples collected in 24 sites in southern France covering urban, industrial, and agricultural areas in order to identify potential contrasts related to anthropogenic activities. Fifteen pesticides (six fungicides, five insecticides, and four herbicides), including four active compounds currently banned by EU legislation, were detected in at least one site. Lindane, diflufenican, difenoconazole, and boscalid were the most common pesticides found in all sites. Urban sites appeared generally less contaminated compared to industrial and rural ones, but a strong heterogeneity was noticed between locations. The biomonitoring with lichens revealed unexpected contaminated areas, partly due to the use of herbicides for vegetation control in industrial and railway installations. The spatial distribution also suggests an input of pesticides by atmospheric transport at the local and regional scales.

5.
Mar Pollut Bull ; 191: 114898, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37030168

RESUMO

There are few cetacean tissue-specific polycyclic aromatic hydrocarbon (PAH) concentration studies in the Mediterranean, despite this region is among the most subjected to chemical contamination. PAH analyses were conducted in different tissues of striped dolphins (Stenella coeruleoalba, N = 64) and bottlenose dolphins (Tursiops truncatus, N = 9) stranded along the French Mediterranean coastline from 2010 to 2016. Comparable levels were measured in S. coeruleoalba and T. trucantus (1020 and 981 ng g-1 lipid weight in blubber, 228 and 238 ng g-1 dry weight in muscle, respectively). The results suggested a slight effect of maternal transfer. The greatest levels were recorded by urban and industrial centers, and decreasing temporal trends were observed in males muscle and kidney, but not in other tissues. As a conclusion, the elevated levels measured could represent a serious threat to dolphins populations in this region, particularly by urban and industrial centers.


Assuntos
Golfinho Nariz-de-Garrafa , Stenella , Animais , Masculino , Cetáceos , Mar Mediterrâneo
6.
Mar Pollut Bull ; 174: 113198, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34875476

RESUMO

Although banned for years, organochlorine pesticides and PCBs continue to affect aquatic life, dolphins being particularly exposed. The concentrations of 31 PCB congeners, and 15 banned pesticides or metabolites were measured in 5 tissues of 68 striped dolphins stranded in the Northwestern Mediterranean coast in 2010-16. The results were compared to historical data (1988-2009) and, even though there is a slow decreasing trend, the levels in the 2010-2016 samples were still elevated based on common cetacean toxicological thresholds. A transition period in 2007-08, probably caused by a morbillivirus epizootic amplified the stranding, espacially of highly contaminated specimens. From 2010, higher proportions in parent compounds towards metabolites were observed yet again. These changing patterns were likely reflect the exposure of dolphins to the remobilization of pollutants from contaminated soils and sediments, with a prominent role of rivers. This should lead to an even slower decline of these contaminants that could last for decades, requiring new efforts to reduce their dispersal to aquatic ecosystems.


Assuntos
Infecções por Morbillivirus , Praguicidas , Bifenilos Policlorados , Stenella , Animais , Ecossistema , Mar Mediterrâneo , Bifenilos Policlorados/análise
7.
J Trace Elem Med Biol ; 73: 127021, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35753173

RESUMO

OBJECTIVES: We sought to determine whether the residents living closer to the core industrial zone (Fos-sur-Mer) had higher trace metals blood and urinary levels than residents who lived further away (Saint-Martin-de-Crau). MATERIALS AND METHODS: As part of The INDEX study, we measured the following trace metals into blood and urine samples of 138 participants (80 in the core industrial zone and 58 in the reference area): Antimony, Arsenic, Cadmium, Chromium, Cobalt, Mercury, Nickel, Lead and Vanadium. Participants were recruited using a stratified random sampling method and had to meet the following inclusion criteria: 30-65 years old, living in the area since at least 3 years, not working in the industrial sector, non-smoker. We used single-pollutant multivariate linear regression models, using substitution when censored data were under 15 % and Tobit models alternatively, adjusting for personal physiological, social, dietary, housing characteristics and leisure activities. We also measured these trace metals in samples of lichens (Xanthoria parietina) and atmospheric particles (PM2.5). RESULTS: We showed higher lichen and air levels of several metals (Cd, Cr, Co, Ni and Pb) in the exposed area. Living close to the core industrial zone was significantly associated with an increase in blood levels of lead (adjusted geometric mean = 17.2 [15.8-18.7] vs 15.1 [13.7-16.7] µg.L-1, p < 0.05). We report significant increase of some metals urinary levels among residents of the industrial port zone, as the result of the use of the environment, itself contaminated by industrial activities: dietary history of self-consumption of vegetables (Cadmium), eggs and poultries (Vanadium). However, Vanadium levels were greater among self-consumers of poultry in the reference area and gardeners had circulatory levels of Lead greater than non-gardeners only in the reference area. Consumption of non-local sea-products increased the level of Cadmium. CONCLUSIONS: These results brought interesting clues, in complement to national programs, regarding the exposure to trace metals of residents living in a major industrial harbor.


Assuntos
Arsênio , Poluentes Ambientais , Líquens , Metais Pesados , Oligoelementos , Adulto , Idoso , Arsênio/urina , Cádmio/urina , Exposição Dietética , Monitoramento Ambiental/métodos , Humanos , Pessoa de Meia-Idade , Vanádio
8.
Environ Pollut ; 309: 119742, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35835273

RESUMO

2,4,6-tribromophenol (TBP) is implied in the production of brominated flame retardants but is also a major chlorination by-product in seawater. A growing number of studies indicate that TBP is highly toxic to the marine biota, but the contribution of anthropogenic sources among natural production is still under question concerning its bioaccumulation in marine organisms. Here, several water sampling campaigns were carried out in the industrialized Gulf of Fos (northwestern Mediterranean Sea, France) and clearly showed the predominant incidence of industrial chlorination discharges on the TBP levels in water, at the 1-10 ng L-1 level in average and reaching up to 580 ng L-1 near the outlets. The bioaccumulation of TBP was measured in 90 biota samples from the Gulf of Fos. The concentrations found in European conger muscle tissues (140-1000 ng g-1 lipid weight, in average), purple sea urchin gonads (830-880 ng g-1 lipid weight, in average), and Mediterranean mussel body (1500-2000 ng g-1 lipid weight, in average) were above all published references. Significant correlations with fish length (European conger) and gonad somatic index (purple sea urchin) were also identified. Comparatively, fish, urchins and mussels from other Mediterranean sites analyzed within this study showed a lower bioaccumulation level of TBP, consistently with what found elsewhere. Industrial outflows were thus identified as hotspots for TBP in seawater and marine organisms. The environmental risk assessment indicated a high potential toxicity in the industrial Gulf of Fos, in particular near the outlets, and a limited threat to human but toxicological references are lacking.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Peixes , Halogenação , Humanos , Lipídeos , Fenóis , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
9.
Langmuir ; 27(6): 2625-33, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21332215

RESUMO

The removal of chloride, nitrate, and sulfate ions from wastewaters by a macroporous ion-exchange resin is studied through the experimental results obtained for six ion exchange systems, OH(-)/Cl(-), OH(-)/NO3(-), OH(-)/SO4(2-), and HCO3(-)/Cl(-), Cl(-)/NO3(-), Cl(-)/SO4(2-). The results are described through thermodynamic modeling, considering either an ideal or a nonideal behavior of the ionic species in the liquid and solid phases. The nonidealities are determined by the Davies equation and Wilson equations in the liquid and solid phases, respectively. The results show that the resin has a strong affinity for all the target ions, and the order of affinity obtained is OH(-) < HCO3(-) < Cl(-) < NO3(-) < SO4(2-). The calculation of the changes in standard Gibbs free energies (ΔG(0)) shows that even though HCO3(-) has a lower affinity to the resin, it may affect the removal of Cl(-), and in the same way that Cl(-) may affect the removal of NO3(-) and SO4(2-). The application of nonidealities in the thermodynamic model leads to an improved fit of the model to the experimental data with average relative deviations below 1.5% except for the OH(-)/SO4(2-) system. On the other hand, considering ideal or nonideal behaviors has no significant impact on the determination of the selectivity coefficients. The thermodynamic modeling is also compared with the Dubinin-Astakhov adsorption isotherms obtained for the same ion exchange systems. Surprisingly, the latter performs significantly better than the ideal thermodynamic model and nearly as well as the nonideal thermodynamic model.


Assuntos
Resinas de Troca Aniônica/química , Cloretos/isolamento & purificação , Simulação de Dinâmica Molecular , Nitratos/isolamento & purificação , Sulfatos/isolamento & purificação , Termodinâmica , Cloretos/química , Nitratos/química , Sulfatos/química
10.
Environ Sci Pollut Res Int ; 28(45): 64253-64267, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34302251

RESUMO

The bioaccumulation of metals (As, Cd, Co, Cr, Cu, Ni, Pb, Sb, V, Zn, Al, Fe) and organochlorine compounds (PCDD-Fs and PCBs) was assessed in soils and vegetables of 3 sites of contrasted anthropogenic influence (rural and industrial-urban areas). Cultivated soils in industrial areas exhibited diffuse pollution in organochlorine pollutants (PCBs and PCDD-Fs). The pollutant levels encountered in vegetables were always lower than the EU regulatory or recommended values. However, the contents measured in vegetables cultivated near industrialized areas were significantly higher than those observed in rural areas. This was notably the case for Co, Cd, Cr, Ni, Pb, V, NDL- and DL-PCB, PCDD, and PCDF. The leaf pathway appeared as the main absorption pathway for many contaminants. The results suggested that population exposure to pollutants was mainly caused by vegetable ingestion. In the vegetables and soils, the toxicity was mainly caused by the V, Co, Cd, and Pb contents to which can be added As and PCDD-Fs for soils. Therefore, the proximity of vegetable crops to highly anthropised areas has led to long-term exposure of vegetables and soils to air pollutants, leading to an accumulation in the food chain and thus a risk for human health.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Verduras
11.
J Chromatogr A ; 1612: 460675, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31708216

RESUMO

Lichens are effective atmospheric bioindicators, and the bioaccumulation of pollutants is frequently measured in their tissues to assess contamination levels. Even though monosaccharide anhydrides are not directly considered as contaminants, Levoglucosan is a common tracer of biomass burning in atmospheric samples and measuring their accumulation in lichens could help to evaluate the main atmospheric pollution sources on a spatially resolved scale depending on the size of the sampling grid. In this work, a realiable analytical method to determine monosaccharide anhydrides in liches was developed. It is based on ASE extraction, solid phase extraction to clean the sample, and silylation derivatization before GC/MS analysis. The reliability and detection limits of the method were suited to the analysis of lichen samples, and additional quality tests achieved the validation of the method with lichen test matrix. Finally field samples were quantified and the results obtained were consistent with atmospheric levels.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Líquens/química , Monossacarídeos/análise , Biomassa , Limite de Detecção , Extração Líquido-Líquido , Cloreto de Metileno/química , Monossacarídeos/isolamento & purificação , Extração em Fase Sólida , Sonicação
12.
Int J Hyg Environ Health ; 222(1): 1-8, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031710

RESUMO

Chlorination of seawater is one of the most effective technologies for industrial biofouling control. However, chlorination leads to the formation of halogenated chlorination byproducts (CBPs) associated with potential risks to environmental and human health. The present study investigated the occurrence and distribution of CBPs in the Gulf of Fos, a semi-enclosed bay where chlorinated effluents of multiple industrial plants are discharged. Seawater samples (surface and bottom) were collected at 24 sampling stations, with some near industrial outlets and others dispersed throughout the bay. Sediment samples were also collected at 10 sampling stations. Physicochemical parameters including water temperature, pH, salinity, bromide content, and free and total residual oxidant were determined. Several chemical classes of CBPs including trihalomethanes, haloacetic acids, haloacetonitriles, trihaloacetaldehydes, and halophenols were analyzed. Bromoform was the most abundant CBP in seawater, and it was detected at most of the sampling stations of the bay with highest concentrations occurring near the industrial effluent outlets. Dibromoacetic acid was the second most abundant CBP at most of the sites followed by dibromoacetonitrile. Other detected CBPs included tribromoacetic acid, bromochloroacetonitrile, and bromal hydrate. To our knowledge, the concentration of the latter CBP was reported here for the first time in the context of industrial seawater chlorination. In sediments, two bromine-containing halophenols (2-chloro-4-bromophenol and 2,4,6-tribromophenol) were detected at two sampling stations. Ecotoxicological assays and risk assessment studies based on the detected environmental concentrations are warranted to elucidate the impacts of marine CBP contamination.


Assuntos
Hidrocarbonetos Clorados/análise , Sedimentos Geológicos/análise , Hidrocarbonetos Clorados/química , Água do Mar/análise
13.
Environ Sci Pollut Res Int ; 25(9): 8364-8376, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29307061

RESUMO

Lichen samples from contrasted environments, influenced by various anthropic activities, were investigated focusing on the contaminant signatures according to the atmospheric exposure typologies. Most of the contaminant concentrations measured in the 27 lichen samples, collected around the industrial harbor of Fos-sur-Mer (France), were moderate in rural and urban environments, and reached extreme levels in industrial areas and neighboring cities (Al up to 6567 mg kg-1, Fe 42,398 mg kg-1, or ΣPAH 1417 µg kg-1 for example). At the same time, a strong heterogeneity was noticed in industrial samples while urban and rural ones were relatively homogeneous. Several metals could be associated to steel industry (Fe, Mn, Cd), road traffic, and agriculture (Sb, Cu, Sn), or to a distinct chemical installation (Mo). As well, PCDFs dominated in industrial samples while PCDDs prevailed in urban areas. The particularities observed supported the purpose of this work and discriminated the contributions of various atmospheric pollution emission sources in lichen samples. A statistical approach based on principal component analysis (PCA) was applied and resolved these potential singularities into specific component factors. Even if a certain degree of mixing of the factors is pointed out, relevant relationships were observed with several atmospheric emission sources. By this methodology, the contribution of industrial emissions to the atmospheric metal, PAH, PCB, and PCDD/F levels was roughly estimated to be 60.2%, before biomass burning (10.2%) and road traffic (3.8%). These results demonstrate that lichen biomonitoring offers an encouraging perspective of spatially resolved source apportionment studies.


Assuntos
Monitoramento Ambiental/métodos , Líquens/química , Metais/química , Dibenzodioxinas Policloradas/análise , Cidades , França , Indústrias , Metais/análise , Dibenzodioxinas Policloradas/química
14.
J Chromatogr A ; 963(1-2): 259-64, 2002 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-12187978

RESUMO

A procedure for determination of methyl tert.-butyl ether (MTBE) in water by headspace solid-phase microextraction (HS-SPME) has been developed. The analysis was carried out by gas chromatography with flame ionization detection. The extraction procedure, using a 65-microm poly(dimethylsiloxane)-divinylbenzene SPME fiber, was optimized following experimental design. A fractional factorial design for screening and a central composite design for optimizing the significant variables were applied. Extraction temperature and sodium chloride concentration were significant variables, and 20 degrees C and 300 g/l were, respectively chosen for the best extraction response. With these conditions, an extraction time of 5 min was sufficient to extract MTBE. The calibration linear range for MTBE was 5-500 microg/l and the detection limit 0.45 microg/l. The relative standard deviation, for seven replicates of 250 microg/l MTBE in water, was 6.3%.


Assuntos
Cromatografia Gasosa/métodos , Éteres Metílicos/análise , Poluentes Químicos da Água/análise , Calibragem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
J Chromatogr A ; 1047(1): 111-6, 2004 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-15481466

RESUMO

A procedure for the determination of fatty acids (FA) and glycerol in oils has been developed. The method includes a derivatization step of the FAs into their methyl esters or a transesterification of the triacylglycerols with trimethylsulfonium hydroxide (TMSH), respectively. The analysis is carried out by gas chromatography with parallel flame ionization and mass spectrometric detection. The parameters involved in the transesterification reaction were optimized. Only the stoichiometric ratio of TMSH:total FA amount showed a significant influence on the reaction yield. Relative standard deviations for 10 replicates were below 3% for all FAs studied and their linearity range was 0.5-50 mmol/L, when using heptadecanoic acid as an internal standard. The final procedure was rapid and required little sample handling. It was then tested on fresh oil samples and presented satisfying results, in agreement with previous works.


Assuntos
Arte , Cromatografia Gasosa/métodos , Indicadores e Reagentes/química , Óleos/análise , Compostos de Sulfônio/química , Padrões de Referência
16.
J Hazard Mater ; 190(1-3): 300-7, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21497015

RESUMO

The removal of chloride, nitrate and sulfate ions from aqueous solutions by a macroporous resin is studied through the ion exchange systems OH(-)/Cl(-), OH(-)/NO(3)(-), OH(-)/SO(4)(2-), and HCO(3)(-)/Cl(-), Cl(-)/NO(3)(-), Cl(-)/SO(4)(2-). They are investigated by means of Langmuir, Freundlich, Dubinin-Radushkevitch (D-R) and Dubinin-Astakhov (D-A) single-component adsorption isotherms. The sorption parameters and the fitting of the models are determined by nonlinear regression and discussed. The Langmuir model provides a fair estimation of the sorption capacity whatever the system under study, on the contrary to Freundlich and D-R models. The adsorption energies deduced from Dubinin and Langmuir isotherms are in good agreement, and the surface parameter of the D-A isotherm appears consistent. All models agree on the order of affinity OH(-)

Assuntos
Adsorção , Resinas de Troca Aniônica/química , Ânions/isolamento & purificação , Modelos Químicos , Poluentes Químicos da Água/isolamento & purificação , Cloretos/isolamento & purificação , Nitratos/isolamento & purificação , Sulfatos/isolamento & purificação , Termodinâmica , Purificação da Água/métodos
17.
Anal Chim Acta ; 618(2): 184-95, 2008 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-18513539

RESUMO

An analytical method for the quantitative determination of the total nitro functional group (R-NO2) content in atmospheric particulate organic matter is developed. The method is based on the selectivity of NO2(-) (m/z 46) precursor ion scanning (PAR 46) by atmospheric pressure chemical ionization-tandem mass spectrometry (APCI-MS/MS). PAR 46 was experimented on 16 nitro compounds of different molecular structures and was compared with a neutral loss of NO (30 amu) technique in terms of sensitivity and efficiency to characterize the nitro functional groups. Covering a wider range of compounds, PAR 46 was preferred and applied to reference mixtures containing all the 16 compounds under study. Repeatability carried out using an original statistical approach, and calibration experiments were performed on the reference mixtures proven the suitability of the technique for quantitative measurements of nitro functional groups in samples of environmental interest with good accuracy. A linear range was obtained for concentrations ranging between 0.005 and 0.25 mM with a detection limit of 0.001 mM of nitro functional groups. Finally, the analytical error based on an original statistical approach applied to numerous reference mixtures was below 20%. Despite of potential artifacts related to nitro-alkanes and organonitrates, this new methodology offers a promising alternative to FT-IR measurements. The relevance of the method and its potentialities are demonstrated through its application to aerosols collected in the EUPHORE simulation chamber during o-xylene photooxidation experiments and in a suburban area of a French alpine valley during summer.

18.
Anal Chim Acta ; 605(1): 61-9, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18022412

RESUMO

The present study describes the development of a new analytical technique for the functional group determination of the carboxylic moiety using atmospheric pressure chemical ionization-mass spectrometry (APCI-MS/MS) operated in the constant neutral loss scanning (CNLS) mode. Carboxylic groups were first derivatized into their corresponding methyl esters by reacting with BF3/methanol mix and the reaction mixture was then directly injected into the APCI chamber. The loss of methanol (m/z = 32 amu) resulting from the fragmentation of the protonated methyl esters was then monitored. Applying this method together with a statistical approach to reference mixtures containing 31 different carboxylic acids at randomly calculated concentrations demonstrated its suitability for quantitative functional group measurements with relative standard deviations below 15% and a detection limit of 0.005 mmol L(-1). Its applicability to environmental matrices was also shown through the determination of carboxylic acid concentrations inside atmospheric aerosol samples. To the best of our knowledge, it is the first time that the tandem mass spectrometry was successfully applied to functional group analysis, offering great perspectives in the characterization of complex mixtures which are prevailing in the field of environmental analysis as well as in the understanding of the chemical processes occurring in these matrices.

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