RESUMEN
XAD-2® passive samplers (PAS) have been exposed simultaneously for 14 days on two sites, one rural and one urban, situated in Alsace (East of France) during intensive pesticides application in agriculture (between March and September). PAS have been extracted and analyzed for current-used pesticides and lindane with an analytical method coupling accelerated solvent extraction (ASE), solid-phase microextraction (SPME) and GC/MS/MS. Results show the detection of pesticides is linked to the period of application and spatial and temporal variabilities can be observed with these PAS during the selected sampling period. The spatial and temporal variability is comparable to the one previously observed by comparing data obtained with PAS with data from Hi.-Vol. samplers in an urban area. Sampling rates were calculated for some pesticides and values are comparable to the data already available in the literature. From these sampling rates, concentrations in ng m-3 of pesticides in PAS have been calculated and are in the same order of magnitude as those obtained with Hi.Vol. sampling during the same period of time.
Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/instrumentación , Plaguicidas/análisis , Ciudades , Monitoreo del Ambiente/métodos , Francia , Microextracción en Fase Sólida , Análisis Espacio-Temporal , Espectrometría de Masas en TándemRESUMEN
Atmospheric samples have been collected between 14 March and 12 September 2012 on a 2-week basis (15 days of sampling and exchange of traps each 7 days) in Strasbourg (east of France) for the analysis of 43 pesticides. Samples (particle and gas phases) were separately extracted using Accelerated Solvent Extraction (ASE) and pre-concentrated by Solid Phase Micro-Extraction (SPME) before analysis by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Four SPME consecutive injections at distinct temperatures were made in order to increase the sensitivity of detection for the all monitored pesticides. Currently used detected pesticides can be grouped in four classes; those used in maize crops (acetochlor, benoxacor, dicamba, s-metolachlor, pendimethalin, and bromoxynil), in cereal crops (benoxacor, chlorothalonil, fenpropimorph, and propiconazole), in vineyards (tebuconazole), and as herbicides for orchards, meadows of green spaces (2,4-MCPA, trichlopyr). This is in accordance with the diversity of crops found in the Alsace region and trends observed are in accordance with the period of application of these pesticides. Variations observed permit also to demonstrate that the long time sampling duration used in this study is efficient to visualize temporal variations of airborne pesticides concentrations. Then, long time high-volume sampling could be a simple method permitting atmospheric survey of atmospheric contamination without any long analysis time and consequently low cost.
Asunto(s)
Agroquímicos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Cromatografía de Gases , Ciudades , Francia , Cromatografía de Gases y Espectrometría de Masas/métodos , Plaguicidas/química , Extracción en Fase Sólida , Espectrometría de Masas en TándemRESUMEN
An analytical method associating accelerated solvent extraction (ASE) and solid-phase micro-extraction (SPME) in immersion mode combined with gas chromatography dual electrons capture detectors (SPME-GC-2ECD) has been developed and studied for the simultaneous determination of 19 organochlorine pesticides (OCPs) and 22 polychlorinated biphenyls (PCBs) in air samples (active and XAD-2 passive samplers). Samples were extracted with ASE with acetonitrile using the following conditions: temperature, 150 °C; pressure, 1500 psi; static, 15 min; cycles, 3; purge, 300 s; flush, 100 %. Extracts were reduced to 1 mL, and 500 µL of this extract, filled with deionised water, was subject to SPME extraction. Experimental results indicated that the proposed method attained the best extraction efficiency under the optimised conditions: extraction of PCB-OCP mixture using 100-µm PDMS fibre at 80 °C for 40 min with no addition of salt. The performance of the proposed ASE-SPME-GC-2ECD methodology with respect to linearity, limit of quantification and detection was evaluated by spiking of XAD-2 resin with target compounds. The regression coefficient (R (2)) of most compounds was found to be high of 0.99. limits of detection (LODs) are between 0.02 and 4.90 ng m(-3), and limits of quantification (LOQs) are between 0.05 and 9.12 ng m(-3) and between 0.2 and 49 ng/sampler and 0.52 and 91 ng/sampler, respectively, for XAD-2 passive samplers. Finally, a developed procedure was applied to determine selected PCBs and OCPs in the atmosphere.
Asunto(s)
Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Cromatografía de Gases/métodos , Electrones , Cromatografía de Gases y Espectrometría de Masas/métodos , Límite de Detección , Extracción en Fase Sólida/métodos , Solventes/química , AguaRESUMEN
Most of Polycyclic Aromatic Hydrocarbons (PAHs) are associated to airborne particles and their health impact depends on the particle size where they are bound. This work aims to develop a high sensitive analytical technique to quantify particulate PAHs sampled with a 3-stages cascade impactor in order to derive simultaneously their individual concentration in PM1, PM2.5 and PM10. Three key steps of the method were evaluated separately in order to avoid any PAHs loss during the global sample preparation procedure: (1) the accelerated solvent extraction of PAHs from the filter; (2) the primary concentration of the extract until 1 mL by means of a rotary evaporator at 45°C and 220 mbar and (3) the final concentration of the pre-concentrated extract to about 100-150 µL under a gentle nitrogen stream. Each recovery experiment was realized in triplicates. All these steps evaluated independently show that the overall PAHs loss, even for those with a low molecular weight, should not exceed more than a few percent. Extracts were then analyzed by using a HPLC coupled to fluorescence and Diode Array Detectors with the external standard method. The resulting calibration curves containing between 9 and 12 points were plotted in the concentration range of 0.05-45 µg L(-1) for most of the 16 US-EPA priority PAHs and were fully linear (R(2)>0.999). Limits Of Quantification were in the range 0.05-0.47 µg L(-1) corresponding to 0.75-7.05 pg m(-3) for 20 m(3) of pumped air. Finally, taking into account the average PAHs concentrations previously reported in typical European indoor environments, and considering the use of a 3-stages cascade impactor to collect simultaneously PM>10 µm, 2.5 µmAsunto(s)
Contaminantes Atmosféricos/análisis
, Contaminación del Aire Interior/análisis
, Cromatografía Líquida de Alta Presión/métodos
, Material Particulado/análisis
, Hidrocarburos Policíclicos Aromáticos/análisis
, Solventes/química
, Contaminantes Atmosféricos/aislamiento & purificación
, Monitoreo del Ambiente/métodos
, Fluorescencia
, Límite de Detección
, Material Particulado/aislamiento & purificación
, Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación
RESUMEN
Cascade Impactor is a powerful sampling method to collect airborne particles as a function of their size. The 3-stages Cascade Impactor used in this study allowed to sample simultaneously particles with aerodynamic diameter Dae>10 µm, 2.5 µmAsunto(s)
Contaminantes Atmosféricos/análisis
, Contaminación del Aire Interior/análisis
, Monitoreo del Ambiente/métodos
, Hidrocarburos Policíclicos Aromáticos/análisis
, Contaminación del Aire Interior/estadística & datos numéricos
, Ambiente
, Monitoreo del Ambiente/instrumentación
, Francia
, Humanos
, Tamaño de la Partícula