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Acetone is ubiquitous in the troposphere. Several papers have focused in the past on its gas phase reactivity and its impact on tropospheric chemistry. However, acetone is also present in atmospheric water droplets where its behaviour is still relatively unknown. In this work, we present its gas/aqueous phase transfer and its aqueous phase photooxidation. The uptake coefficient of acetone on water droplets was measured between 268 and 281 K ( γ = 0.7 × 10 −2 –1.4 × 10 −2 ), using the droplet train technique coupled to a mass spectrometer. The mass accommodation coefficient α (derived from γ ) was found in the range (1.0–3.0 ± 0.25) × 10 −2 . Henry’s law constant of acetone was directly measured between 283 and 298 K using a dynamic equilibrium system ( H (298K) = (29 ± 5) M atm −1 ), with the Van’t Hoff expression ln H ( T ) = (5100 ± 1100)/ T − (13.4 ± 3.9). A recommended value of H was suggested according to comparison with literature. The OH-oxidation of acetone in the aqueous phase was carried out at 298 K, under two different pH conditions: at pH = 2, and under unbuffered conditions. In both cases, the formation of methylglyoxal, formaldehyde, hydroxyacetone, acetic acid/acetate and formic acid/formate was observed. The formation of small amounts of four hydroperoxides was also detected, and one of them was identified as peroxyacetic acid. A drastic effect of pH was observed on the yields of formaldehyde, one hydroperoxide, and, (to a lesser extent) acetic acid/acetate. Based on the experimental observations, a chemical mechanism of OH-oxidation of acetone in the aqueous phase was proposed and discussed. Atmospheric implications of these findings were finally discussed.

Adsorption study of benzaldehyde on ice surfaces is performed by combining experimental and theoretical approaches. The experiments are conducted over the temperature range 233-253 K using a coated wall flow tube coupled to a mass spectrometric detector. Besides the experimental way, the adsorption isotherm is also determined by performing a set of grand canonical Monte Carlo simulations at 233 K. The experimental and calculated adsorption isotherms show a very good agreement within the corresponding errors. Besides, both experimental and theoretical studies permit us to derive the enthalpy of adsorption of benzaldehyde on ice surfaces DeltaH(ads), which are in excellent agreement: DeltaH(ads) = -61.4 +/- 9.7 kJ/mol (experimental) and DeltaH(ads) = -59.4 +/- 5.1 kJ/mol (simulation). The obtained results indicate a much stronger ability of benzaldehyde of being adsorbed at the surface of ice than that of small aliphatic aldehydes, such as formaldehyde or acetaldehyde. At low surface coverages the adsorbed molecules exclusively lie parallel with the ice surface. With increasing surface coverage, however, the increasing competition of the adsorbed molecules for the surface area to be occupied leads to the appearance of two different perpendicular orientations relative to the surface. In the first orientation, the benzaldehyde molecule turns its aldehyde group toward the ice phase, and, similarly to the molecules in the lying orientation, forms a hydrogen bond with a surface water molecule. In the other perpendicular orientation the aldehyde group turns to the vapor phase, and its O atom interacts with the delocalized pi system of the benzene ring of a nearby lying benzaldehyde molecule of the second molecular layer. In accordance with this observed scenario, the saturated adsorption layer, being stable in a roughly 1 kJ/mol broad range of chemical potentials, contains, besides the first molecular layer, also traces of the second molecular layer of adsorbed benzaldehyde.

As bibliometric indicators are objective, reliable, and cost-effective measures of peer-reviewed research outputs, they are expected to play an increasingly important role in research assessment/management. Recently, a bibliometric approach was developed and integrated within the evaluation framework of research funded by the National Cancer Institute of Canada (NCIC). This approach helped address the following questions that were difficult to answer objectively using alternative methods such as program documentation review and key informant interviews: (a) Has the NCIC peer-review process selected outstanding Canadian scientists in cancer research? (b) Have the NCIC grants contributed to increasing the scientific performance of supported researchers? (c) How do the NCIC-supported researchers compare to their neighbors supported by the U.S. National Cancer Institute? Using the NCIC evaluation as a case study, this article demonstrates the usefulness of bibliometrics to address key evaluation questions and discusses its integration, along complementary indicators (e.g., peer ratings), in a practice-driven research evaluation continuum.

The understandings of atmospheric transport of pesticides need the knowledge of pesticides vapour/particles distribution. Different parameters can influence this equilibrium: total suspended particles (TSP), ambient temperature… vapour/particles (V/P) partitioning of PAHs, OCs and PCBs are well documented. Because of their long life-time, most of the OCs are now prohibited in Europe. They are now replaced by new compounds for which few data are available. In this work it is reported that the influence of TSP, relative humidity of and ambient temperature on the V/P partitioning of different current-used pesticides commonly applied in Alsace region. For this study, a filter-XAD-2 resin plug high-volume air sampler was used to collect simultaneously the particle (P) and vapour (V) phases of pesticides simultaneously on three sites (urban, rural and remote). It can be observed that the cited parameters did not influence individually the V/P partitioning of the studied pesticides. This observation shows that the V/P partitioning is the result of the combined influence of all of the parameters. For all of the pesticides, the vapour phase concentration increases with the decrease of the particle concentration and of the temperature. The influence of the temperature was monitored by the use of the Clausius–Clapeyron equation. From this study, it can be shown that the distribution of alachlor in the gas phase was of local origin while for trifluralin and lindane, results indicate the contribution of long-range transport processes on their gas phase distribution.

Aircraft are prolific sources of particles (soot, liquid aerosols and contrails) that can impact cloudiness and affect the Earth's radiative budget balance. In order to study the formation and evolution of these particles, a numerical approach has been developed combining large-eddy simulation (LES) and a detailed microphysical model. Generally very detailed microphysical models are run along a single average trajectory, without any temperature fluctuation. However, this approach may lead to significant differences in particle properties and particle size distribution as it oversimplifies dynamical and mixing processes compared to multidimensional descriptions of aircraft wakes. This may affect the initialisation of meso-scale models, such as, for example, the formation of cloud condensation nuclei from persistent contrails, and heterogeneous chemical reactions. In this paper, we present the results of detailed microphysical processes calculations applied to a large number of fluid parcels trajectories, generated by a LES two-phase flow solver.

An experimental set-up consisting of two parallel absorption cells coupled to a CCD detector was used to determine absolute values of molar absorptivity coefficients ɛ of five herbicides (alachlor, mecoprop-p, pendimethalin, propanil and trifluralin) in methanol. The absorption spectra were measured using a deuterium lamp at room temperature (298 ± 2 K) over the wavelength range 240–340 nm, except for pendimethalin and trifluralin where the wavelength range was extended to 240–550 nm. Absorbances were also measured at 253.7 nm using an Hg-lamp in different concentrations range depending on the studied compound. Except for mecoprop-p where absorbances were too low at this wavelength, the absolute values of molar absorptivity coefficients at 253.7 nm were determined according to the Beer–Lambert's law: ɛ = 381 ± 28 for alachlor, ɛ = 11,240 ± 1030 for pendimethalin, ɛ = 22,220 ± 1850 for propanil and ɛ = 5720 ± 410 for trifluralin (in units of M −1 cm −1 ). The quoted errors correspond to 2 σ obtained from the least square fit analysis and the estimated systematic error of 5% due to the uncertainties in aqueous concentrations. For all the studied compounds, the absorbances measured were lower than two and did not exhibit any deviation from the Beer–Lambert's law.

While using alternative aviation fuels represents a promising approach to reduce the industry’s impact on climate change and local air quality, the influence of these new fuels on the chemical composition of exhaust plumes, and, in particular, on aviation-produced aerosols must be assessed. This paper studies the influence of using alternative jet fuels on induced particles, including contrails, in a near field of an aircraft. A computational model with detailed microphysics taking into account the condensation of organic species, homogeneous freezing, and soot activation was used to study the effect of different fuels on the formation and evolution of particulate matter in the exhaust plume of an aircraft flying at cruise conditions. Three different fuels were considered and compared: conventional kerosene (Jet A-1); a pure alternative fuel (with similar properties as Fischer–Tropsch (FT) or hydro-processed esters and fatty acids (HEFA) fuels); and a blend consisting of a 50/50 mixture of kerosene and the mentioned alternative fuel. Several conclusions can be drawn when using pure alternative and blended fuels instead of standard kerosene. The contribution of soluble organic matter in the composition of mixed aerosols increased on average by 29% with Jet A-1 to 45% with a blended fuel. The reduction in soot particles favors the homogeneous freezing pathway and the ice crystals formed were larger and evidenced lower number densities. The background particles can no longer be neglected, since they can account for more than 50% of the particles after 5 s behind the nozzle exit. All these changes are expected to alter the optical properties of contrails.

Quaternary Ammonium Compounds (QACs) are widely found in disinfectants used in hospitals. Benzalkonium chloride (BAC) and didecyldimethylammonium chloride (DDAC) predominate in the disinfecting formulations. These compounds are strong irritants and can play a role in the induction of Occupational Asthma among the professionals of health and cleaning. In order to evaluate the potential health effect of these quaternary ammonium compounds to hospital employers, the development of an analytical method for their quantification in indoor air was developed. DDAC aerosols are trapped by adsorption on XAD-2 resin SKC tube. The air in hospital buildings was sampled using a constant debit Gillian pump at a flow of 1.0 l/min (+/-5%). Ion Chromatography (IC) was chosen for the analysis of DDAC especially for its high sensitivity and specificity. The Limit of Detection (LOD) by IC for DDAC is 0.56 mug/ml. Therefore the LOD of atmospheric DDAC is 28 microg/m(3) with an air volume of 100 l and a desorption volume of 5 ml. All DDAC air samples were lower than the LOD of the analytical method by IC. Under the standard conditions of use of the disinfecting solutions (Surfanios, Ampholysine Plus and Amphospray 41), the insignificant volatility of DDAC would not seem to be able to contaminate the indoor hospital atmosphere during the disinfection process. However, the DDAC can contaminate working atmospheres if it is put in suspension by aerosolisation.

Solid-phase microextraction (SPME) was used for the analysis of some pesticides (bromoxynil, chlorotoluron, diuron, isoproturon, 2,4-MCPA, MCPP and 2,4-D) in rainwater after derivatisation with PFBBr and gas chromatography-ion trap mass spectrometry. The derivatisation procedure was optimized by testing different methods: direct derivatisation in the aqueous phase followed by SPME extraction, on-fibre derivatisation and derivatisation in the injector. The best result was obtained by headspace coating the PDMS/DVB fibre with PFBBr for 10 min followed by direct SPME extraction for 60 min at 68 degrees C (pH 2 and 75% NaCl). Good detection limits were obtained for all the compounds: these ranged between 10 and 1,000 ng L-1 with a relatively high uncertainty due to the combination of derivatisation and SPME extraction steps. The optimized procedure was applied to the analysis of pesticides in rainwater and results obtained shows that this method is a fast and simple technique to assess the spatial and temporal variations of concentrations of pesticides in rainwater.

A dynamic dilution system was used for the study of the influence of ozone on the sampling and storage of volatile organic compounds (VOCs) at 0, 4, 7 and 14 days in “TO-Can” canisters at two ozone concentrations, 60 and 150 ppbv. Among the 31 ozone precursors VOCs, a representative mixture containing five alkenes, five aromatics, acetylene and 1,3 butadiene was selected using the Clausius–Clapeyron equation. Here, we demonstrate that the presence of ozone have no influence on the concentrations of VOCs after 14 days storage period and consequently no problem of representativity of the sampling appears after 14 days of storage. The main explanation is the degradation of ozone in contact with deactivated walls of canisters.

A solid-phase microextraction – coupled to a gas chromatography – ion trap tandem mass spectrometry (SPME–GC–MS/MS) method was developed for the quantitative determination in rainwater of 8 pesticides amongst the most used in France and 3 triazines metabolites. The main factors affecting the SPME process were studied. Using a 3 mL sample, the method developed showed good linearity for concentrations ranging from 0.05 to 50 μg L−1 with correlation coefficients between 0.997 and 0.9999 and relative standard deviations (% RSD) below 14%. The study of matrix effects showed that rainwater was too diluted to have any significant influence on the extraction efficiency. To validate the method, a field campaign was carried out on the rain events, which occurred in Strasbourg during a one-year period. The rain concentrations showed patterns of high pesticide concentrations during spring months, which were correlated to the spraying periods of most of these substances.

A multiresidue method using gas chromatography coupled to ion trap tandem mass spectrometry (GC-ITD-MS/MS) associated with solid phase microextraction (SPME) was developed for the analysis of 20 pesticides commonly used in the Alsace region in rainwater samples. Since the pesticides were expected to be present at very low concentrations and in complex matrices, the analytical method used was both highly selective and sensitive. Therefore, fibers coated with polyacrylate (PA), polydimethylsiloxane (PDMS) and polydimethylsiloxane-divinylbenzene (PDMS-DVB) were tested, and the parameters affecting the precision and accuracy of the SPME method were investigated and optimized. These parameters include the type of fiber, the adsorption time, the effect of salt, and the extraction temperature. The PDMS fiber was the most polyvalent for the extractions of the different pesticides studied. Detection limits of between 5 and 500 ng L(-1), depending on the compounds under study (except for those which could not be analyzed: captan and mevinphos), were obtained with this analytical procedure. This method was applied to the analysis of rainwater samples collected simultaneously on a weekly basis at one rural and one urban site between March 2002 and July 2003. While some of the 20 pesticides analyzed were constantly detected (such as lindane and atrazine), a strong temporal variability was observed for some of the others (including alachlor, metolachlor, atrazine).

Atmospheric sampling (gas and particles) of 5 phenols (phenol, m-cresol, p-cresol, o-cresol, pentachlorophenol) and 15 nitrophenols (3-methyl-2-nitrophenol, 3-nitrophenol, 4-methyl-2-nitrophenol, 5-methyl-2-nitrophenol, 2-methyl-3nitrophenol, 3-methyl-4-nitrophenol, 2,6-dinitrophenol, bromoxynil, 2,5-dinitrophenol, 2,6-dinitro-p-cresol, 2,4-dinitrophenol, ioxynil, DNOC, 3,4-dinitrophenol, dinoseb) on XAD-2 resin (20 gr) and glass fibre filters, respectively, were performed in 2002 by using 'Digitel DA80' high volume samplers. These measurements were undertaken in order to show spatial and geographical variations of concentrations and the role of traffic in the emissions of these compounds to the atmosphere. Sampling were performed in Strasbourg (eastern France), in its vicinity (Schiltigheim) and in Erstein. Sites were chosen to be representative of urban (Strasbourg), suburban (Schiltigheim) and rural (Erstein) conditions. Field campaigns were undertaken simultaneously in urban and suburban sites during all the seasons during 4 hours at a flow rate of 60 m3.h-1, which gives a total of 240 m3 of air per sample. Period of sampling varied between 06h00 to 10h00, 11h00 to 15h00 and 18h00 to 22h00 in order to evaluate a variation of concentration during automobile traffic between urban, suburban and rural areas. Gas and particle samples were separately Soxhlet extracted for 12 h with a mixture of CH2Cl2 / n-hexane (50:50 v/v), concentrated to about 1 mL with a rotary evaporated and finally dried under nitrogen. Dry extracts were dissolved in 1 mL of CH3CN. Before analysis, extracts were sylilated by using MTBSTFA. Analysis was performed by GC/MSD in the SIM mode. Partitioning of phenolic compounds between gas and particle phases seems to be mainly correlated with vapour pressure. Among phenolic compounds analysed, phenol, p-cresol, pentachlorophenol and 2.4-dinitrophenol were detected in all samples and emissions from traffic seems to be the major source for the presence of these compounds to the atmosphere. No increase of concentrations in autumn tend to confirm this hypothesis since, with the use of domestic heating in colder months, increases of PAHs concentrations were observed and these compounds are known to be emitted by all combustion processes. Pentachlorophenol is a special case since this molecule is only used as wood preservative. Its presence in all atmospheric samples, whatever the locations and the period of time is the consequence of its persistence. These measurements demonstrate that phenols and nitrophenols are emitted to the atmosphere and further measurements, in order to confirm their sources, their behaviour and their potential impact to the air quality and to human health should be undertaken especially since the literature collected is relatively old. Concentrations of pentachlorophenol measured are very low and, due to its toxicity, further investigations should be undertaken. * The basis of this peer-reviewed paper is a presentation at the 9th FECS Conference on 'Chemistry and Environment', 29 August to 1 September 2004, Bordeaux, France.

A multiresidue method using gas chromatography coupled to ion-trap tandem mass spectrometry (MS/MS) was developed for the analysis of 27 pesticides, commonly used in Alsace, in atmospheric samples (particle and gas phases). As pesticides are expected to be present at very low concentrations and in a complex matrix, the analytical method used was both highly selective and sensitive. These two properties were obtained by associating chromatography with ion-trap MS/MS. To develop this method, analysis of electron impact in single MS was first conducted to choose the parent ions of the pesticides studied. Among the 27 pesticides analysed, seven of them require a derivatisation step. This was the case of some ureas (chlorotoluron, diuron and isoproturon), phenoxy acids (2,4-dichlorophenoxyacetic acid, 4-chloro-2-methylphenoxyacetic acid and mecoprop) and of bromoxynil. The derivatisation was performed with success with pentafluorobenzylbromide. Then, a MS/MS method was optimised by parameters such as the radio frequency storage level and the collision-induced dissociation excitation voltage. Finally, a last step enabled the development of two calibrating programs based on the quantification of daughter ions for the 20 pesticides analysed directly (run 1) and for the seven pesticides which needed derivatisation (run 2). With this analytical procedure, the detection limits varied between 2.5 and 1,250 pg m(-3) depending on the compounds studied. This method was tested with success for atmospheric samples collected in Strasbourg (France) during intensive pesticide treatment in 2002.

A dynamic dilution system was created to evaluate the performance and the reliability of ozone precursor volatile organic compound (VOC) sampling ("TO-Can" canisters) and analysis (thermal desorption/gas chromatography/flame ionisation detection) techniques used by the "Laboratoire Interregional de Chimie du Grand Est (LIC)". Different atmospheres of VOCs were generated at concentrations between 0.8 and 25 ppb, with temperatures of 0, 10, 20 and 30 degrees C, and with relative humidities of 0, 30, 50, 70 and 90%. These conditions are generally representative of those commonly observed in ambient air in the eastern France. This dynamic dilution allows the simulation of a wide range of scenarios (concentrations, temperatures and relative humidities). After assessing the capacity and performance of the system, it was applied in order to evaluate the recoveries and stabilities of VOCs from canisters used for the collection and analysis of two mixtures of VOCs. The first mixture contained six alkanes (ethane, propane, butane, pentane, hexane and heptane), and the second contained five alkenes (ethene, propene, butene, 1-pentene and 1-hexene), five aromatics (benzene, toluene, ethylbenzene, m-xylene and o-xylene), acetylene, and 1,3-butadiene. No significant losses of alkanes from the canisters were observed after 21 days of storage, and good recoveries of alkanes from the canisters (80%) were obtained regardless of the concentration, the temperature and the relative humidity. However, losses of certain aromatics were noted at low relative humidity.

Atmospheric sampling (gas and particles) of PAHs (naphthalene, acenaphthene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[j]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene, dibenz[a,h]anthracene, indeno[1,2,3-cd]pyrene, coronene) on XAD-2 resin (20 g) and glass fiber filters respectively, were performed in 2002 by using Digitel DA80 high-volume samplers equipped with a PM10 head. Samplings were performed in Strasbourg (east of France) and its vicinity (Schiltigheim and Erstein). Sites were chosen to be representative of urban (Strasbourg), suburban (Schiltigheim), and rural (Erstein) conditions. Field campaigns were undertaken simultaneously in urban, and suburban, urban and rural sites during spring and autumn during 4 h at a flow rate of 60 m3/h−1 which gives a total of 240 m3 · h−1 of air per sample. The period of sampling varied between 06:00 to 10:00, 11:00 to 15:00, 17:00 to 21:00 in order to evaluate a vari...

The uptake of dimethyl malonate and dimethyl succinate on aqueous surfaces was measured between 266 and 279 K, using the droplet train technique coupled with mass spectrometric detection. The uptake coefficients A were found to be independent of the aqueous phase composition and of the gas-liquid contact times. In addition, the uptake coefficients and the derived mass accommodation coefficients R show a negative temperature dependence in the temperature ranges studied. The mass accommodations decrease from 7.8 10 -2 to 5.0 10 -2 and from 4.5 10 -2 to 2.3 10 -2 for dimethyl malonate and succinate, respectively. These results are used to discuss the incorporation of oxygenated volatile organic compounds (VOCs) into the liquid using the nucleation theory. Henry’s law constants of both compounds were directly measured between 283 and 298 K using a dynamic equilibrium system. Their values exponentially decrease when temperature increases, from (2.60 ( 0.30) 10 4 to (0.40 ( 0.05) 10 4 and from (1.20 ( 0.10) 10 4 to (0.30 ( 0.03) 10 4 for dimethyl malonate and succinate, respectively (in units of M atm -1 ). The partitioning

In this work, a dynamic system based on the water/air equilibrium at the interface within the length of a microporous tube was used to determine experimentally the Henry's law constants (HLC) of two pesticides: alachlor and dichlorvos. The measurements were conducted over the range 283–298 K. At 298 K, HLC were found to be equal to HLC=(14±2)×103 and HLC=(4.0±0.6)×103 (in units of M atm−1) for alachlor and dichlorvos, respectively. The obtained data were use to derive the following Arrhenius expressions: HLC=(8.0±3.4)×10−10 exp((9200±1600)/T) for alachlor and HLC=(2.8±0.4)×10−13 exp((11 100±1500)/T) for dichlorvos. At a cumulus temperature of 283 K, the fraction of alachlor and dichlorvos in the atmospheric aqueous phase is about 45% and 22%, respectively. Assuming that annual rainfall rate is 1 m/year, the wet deposition lifetimes were then estimated to be of the order of 2.8 days for alachlor and 5.6 days for dichlorvos. These latter are used to compare the relative importance of wet removal towards the lifetime in the gas phase.

The chemical composition of fogwater has been studied in the city of Strasbourg (France) from 1990 to 1999. During these years, fogwater samples have been collected and analysed for major ions and trace metals. This paper reports on the analysis of the collected dataset. The analysis revealed a significant decrease in acidity of approximately one pH unit over the course of the study. This decrease in acidity appears to be linked to a decrease in SO 2(g) and the resulting SO 4 2− . Trace metal concentrations have also strongly decreased over the 10-year period. Pb concentrations, following the elimination of leaded gasoline, decreased by more than one order of magnitude.

A combined study of the OH gas phase reaction and uptake on aqueous surfacesof two carbonates, dimethyl and diethyl carbonate has been carried out todetermine the atmospheric lifetimes of these compounds. Rate coefficients havebeen measured for gas phase reactions of OH radicals with dimethyl and diethylcarbonate. The experiments were carried out using pulsed laser photolysis– laser induced fluorescence over the temperature range 263–372K and the kinetic data were used to derive the following Arrhenius expressions(in units of cm3 molecule−1 s−1):for dimethyl carbonate, k1 = (0.83±0.27)×10−12 exp [−(247± 98)/T] and fordiethyl carbonate, k2 = (0.46±0.15)×10−12 exp [(503± 203)/T]. At 298 K, therate coefficients obtained (in units of 10−12 cm3molecule−1 s−1) are: k1 =(0.35± 0.04) and k2 = (2.31± 0.29). The results arediscussed in terms of structure-activity relationships.The uptake coefficients of both carbonates on aqueous surfaces were measuredas a function of temperature and composition of the liquid phase, using thedroplet train technique coupled to a mass spectrometric detection. Dimethyland diethyl carbonate show very similar results. For both carbonates, themeasured uptake kinetics were found to be independent of the aqueous phasecomposition (pure water, NaOH solutions) but dependent on gas-liquid contacttime which characterises a surface saturation effect. The uptake coefficientvalues show a slight negative temperature dependence for both carbonates.These values vary from 1.4×10−2 to0.6×10−2 in the temperature range of 265–279 Kfor dimethyl carbonate, from 2.4×10−2 to0.9×10−2 in the temperature range of 270–279 Kfor diethyl carbonate. From the kinetic data, the following Henry's lawconstants were derived between 279 and 265 K: dimethyl carbonate,H1 = 20–106 M atm−1; and diethyl carbonate,H2 = 30–98 M atm−1. The reported data showthat the OH reaction is the major atmospheric loss process of these twocarbonates with lifetimes of 33 and 5 days, respectively, while the wetdeposition is a negligible process.

International audience; The global impact of aviation on the atmosphere is generally determined using the total amount of gas and particulate matter emitted at the aircraft engine exit but generally ignore some of the physical transformations occurring at much smaller scales in the aircraft wake. In that work, we present an offline alternative method based on the use of a detailed plume aerosol model combined to fluid trajectories calculated from 3D large-eddy simulations (LES). The study has been limited to the first 10 s behind a type Airbus 340 aircraft. The results have been compared to those obtained from a one-way coupling approach including a simple microphysics water vapor deposition model on soot cores. The respective evolutions of average ice particles radius are in good agreement. Furthermore, different types of aerosol properties are examined including the charged volatile particles, the dry and activated soot and the ice crystals from homogeneous and heterogeneous freezing. The variability of the aerosol size distribution clearly illustrates the influence of the mixing, as a function of the position in the aircraft plume. Finally, the volatile particles distribution exhibits a bimodal shape resulting from the presence of charges, in agreement with that observed in literature.

The uptake of gaseous bromine chloride (BrCl) on aqueous surfaces was measured, as a function of temperature and liquid composition, using the droplet train technique coupled to a mass spectrometer. The uptake rate on pure water was too slow to be directly measured (i.e., γ

In this article, a model which examines the evolution of ion concentrations in a hot aircraft exhaust plume on the ground is proposed. The model includes plume dilution and ion-ion recombination with coefficients which vary with temperature. A comparison of the model is made with the available ground-based experimental data obtained on the ATTAS research aircraft engines. From this comparison, an ion emission index of the order of 8-10 16 ions/kg(fuel) is inferred.

In the present study, included within the framework of a Franco-German Research Program for Conservation of HistoricalMonuments, the chemical composition of rainwater was investigated in Thann (Alsace, France) and in Tours (Indre etLoire, France) between 1992 and 1993. A total of 78 and 24samples, respectively, were collected, near the Thann collegiateand the Tours cathedral on a weekly basis and analysed for Cl-, NO3 -, SO4 2-, Na+, NH4 +, K+, Mg2+ and Ca2+. Results showpH ranged from 3.60 to 6.58 and from 5.49 to 7.01 for Thann andTours, respectively. In Thann, SO4 2- is the major anion and rainwater acidity is neutralised by compounds ofterrigenic origin which come from the soil of the upper Rhinevalley (Ca2+; ‘loess’) and the potash mines of Alsace. In Tours, SO4 2- is also the major anion and the acidity is neutralised partially by atmospheric ammonia and partially by compounds of terrigenic origin and by dust fromthe erosion of the cathedral and the works of restoration, in the form of CaCO3.

A theory is developed for the deliquescence of small particles that incorporates the effect of surface phenomena on the deliquescence process. The theory is based on rudimentary surface thermodynamics since we are primarily interested in the orders of magnitude of the various effects. Applying the theory to a generic crystal with properties similar to NaCl, in water vapor, we find that the surface tension has a significant effect for crystals with a radius smaller than 10−5 cm. We suggest an experiment for the determination of the surface tension of soluble crystals that utilizes the deliquescence of these small particles. Serendipitously, such an experiment has just been performed by another group of authors. The qualitative analysis of this experiment should eventually be accompanied by a further development of the rigorous thermodynamic theory of solid surfaces.

The Kohler theory of activation is compared with classical nucleation theory for the NaCl–H2O system. We find that for NaCl particles of the size typically found in the atmosphere the two processes are hardly distinguishable. Consequently, the usually preferred choice of simple activation theory over nucleation in the development and application of large scale atmospheric models, is reaffirmed. However, we also find that for small NaCl crystals consisting of 10–50 molecules, nucleation can occur at relative humidities significantly lower than those required for activation.

The density and surface tension of the H2SO4/HNO3/H2O ternary system have been measured as a function of temperature from 245 to 298 K. The acid compositions range from 0 to 65 wt % for sulfuric acid and 0 to 45 % for nitric acid. The densities and surface tensions for the ternary system, combined with the data for the two binary mixtures water/nitric acid and water/sulfuric acid have been expressed as polynomials of the nitric acid and sulfuric acid weight % for the temperatures of 253 and 293 K. Since the densities and surface tensions vary linearly with temperature, data at temperatures other than 253 and 293 K can easily been obtained by interpolation.

The uptake kinetics of three different hydrogen halides, i.e., HCl, HBr, and HI, by aqueous surfaces were measured as a function of temperature in the range from 262 to 281 K using the droplet train technique. The reported mass accommodation coefficients (α) were shown to decrease with increasing temperature. For HCl, α decreases from 0.24 to 0.13 when the temperature was raised from 263 to 281 K. In the same temperature range, the mass accommodation of HBr and HI decrease from 0.16 to 0.068 and 0.19 to 0.079, respectively. This temperature trend suggests that the rate-limiting step during the accommodation process is part of the physical solvation process as previously reported for nonreacting gases. The data were accordingly interpreted using a model found in the literature which describes the mass accommodation process as a dynamical nucleation event. The implications for the tropospheric chemistry of these findings are also discussed.

A filter-XAD-2 resin plug high-volume air sampler was used to collect the particle (P) and vapour (V) phases of 11 pesticides. The atmospheric concentrations were measured simultaneously at three sites characterised as remote (Aubure in the Vosges mountains), rural (Colmar, in the upper Rhine Valley), and urban (Strasbourg, in the upper Rhine Valley). The measured concentrations, which agree with those of literature, were used to study the influence of the physico–chemical parameters on the V/P partitioning. The behaviour observed on two organochlorine pesticides (α-HCH and HCB), carbaryl, and trifluraline corresponds to the one presented in literature for organochlorine and PAH. Therefore, the V/P partitioning is mainly controlled by temperature, total suspended particle (TSP), and vapour pressure. Nevertheless, the slope of the regression line of log(A.TSP/F ) against log P°l (where A and F are, respectively, the gas and particulate concentrations and P°l is the subcooled liquid–vapour pressure) is less compared with that presented in literature (0.36 against approximately 0.85). This difference could possibly result from the low TSP concentrations measured in our study. For some pesticides (trifluraline, γ-HCH, mecoprop, carbofuran and atrazine) the description of the V/P partitioning is improved by using relative humidity in addition to the three previous environmental parameters (temperature, TSP and vapour pressure). There seems to exist a competition mechanism between water molecules in gas phase and pesticides to adsorb on the receiving sites of the particles. By this mechanism increase in the atmospheric relative humidity induces a simultaneous increase of pesticides in the gas phase.

The uptake kinetics of N2O5 were studied with the droplet train technique as a function of temperature between 262 and 278 K on different aqueous solutions. No pronounced temperature dependence was observed, and the average uptake coefficient in this temperature range is 0.018 ± 0.003. When interacting with salt solutions (i.e., NaCl, NaBr, or NaI), N2O5 contributes to the formation of ClNO2 and BrNO2. The multiphase chemistry of these nitryl compounds was further investigated using the wetted-wall technique as a function of temperature between 275 and 293 K on different aqueous solutions. The uptake coefficients are reported for both species, and no distinct temperature dependence was observed. Their uptake rate was efficiently enhanced by the presence, in the aqueous phase, of halogenides ions. When reacting with Br- or I-, both nitryl compounds deliver to the gas phase the molecular form of the halogen, i.e., Br2 or I2. A reaction scheme potentially explaining these observations is presented and its im...

The uptake kinetics of methanesulfonic acid (CH3SO3H, MSA) and glyoxal (CHOCHO, ethanedial) by aqueous solutions were studied as a function of temperature using the droplet train technique combined with mass spectrometry and FTIR detection. The measured uptake kinetics for MSA were shown to be independent of the composition of the aqueous phase for NaCl concentrations in the range from 0 to 2 M. The mass accommodation coefficient was determined as a function of temperature between 261 and 283 K. The measured values decreased from 0.16 to 0.1 in this temperature range. The uptake kinetics of glyoxal were studied as a function of temperature between 263 and 283 K and were very close to our detection limit in pure water (i.e., uptake coefficient γ close to 10-3) but were strongly affected by the pH (in the range from 1 to 14) or by sulfite ions (γ increasing to ∼0.02). The rate constant of the reaction between nonhydrated glyoxal and sulfite ions was determined to be ∼7.6 × 106 M-1 s-1 at 283 K. The mass acc...

This work presents the chemical analysis of low weight carboxylic acids: formate and acetate in two droplet-size categories (2–6 and 5–8 μm) of fogwater collected in Strasbourg (eastern France) between 1991 and 1994. For each sample, the ratio between acetate and formate was calculated, in many cases, this ratio was typically higher than one. This calculation indicates that the origin of acetate and formate can be attributed to automobile exhaust. Maximum contribution of these acids to the total free acidity of fogwater was also checked and the results show that the contribution is very low in regard to the strong mineral acids from anthropogenic origin.

The uptake kinetics of ozone (O3) and methyl hydroperoxide (CH3OOH, MHP) by aqueous solutions were studied as a function of temperature using the droplet train technique combined with mass spectrometry detection. The uptake of ozone by pure water was found to be too small to be directly measured. Using NaI as a scavenger increased the uptake coefficient γ from below the detection limit to a range from 0.0037 to 0.0116 for I- activities in the range from 0.3615 to 2.889 at 282 K. From these experiments, we estimated the second-order rate constant for the reaction O3 + I- → products to be in the range 3.2 × 108 to 2.4 × 109 M-1 s-1 for temperature between 275 and 293 K. The activation parameters for this reaction were also estimated. For methyl hydroperoxide, the uptake rate on pure water was fast enough to be directly measured. According to the physicochemical properties of this hydroperoxide, the uptake was mainly due to the diffusion and accommodation processes. It was therefore possible to measure its m...

Steady state rates and time lags for binary homogeneous nucleation of sulfuric acid-water aerosols in aircraft wakes are calculated for relative humidities lower than 100%, i.e., for the case in which no visible contrails form. Formation of the sulfuric acid-water aerosol is shown to depend sensitively on the concentration of sulfuric acid derived from engine exhaust. Nucleation of the sulfuric acid-water aerosol is found to be controlled both by the steady state rate and by the time lag on the timescales relevant to contrail formation. Only for the highest gas-phase acid concentrations are the nucleation time lags sufficiently short that steady state conditions pertain.

The equilibrium partial vapor pressures over the binary solutions H2O/HNO3, H2SO4/H2O, HNO3/H2SO4 and the ternary mixture H2SO4/HNO3/H2O have been re-determined for temperatures below 25°C. The model presented here is valid over the entire range of concentrations, for temperatures in the range 190–298 K. The predictions of this model are compared with the existing measurements and other predictions, both at room temperature and at low temperatures down to about 190 K. The calculated partial pressures agree very well with the available experimental data

Rainwater sampled weekly at nine sites in eastern France from October 1991 to March 1992 has been analysed for major ions (Cl − , NO 3 − , SO s 2− , NH 4 + , Na + , K + , Mg 2+ and Ca 2+ ), pH and conductivity. The major elements are SO 4 2− and Cl − for the anions and NH 4 + and Ca 2+ for the cations. The major ion concentrations are higher in urban areas, especially at Colmar (no.2), where rainfall amounts are low. Surprisingly, the acidity is higher at the sites in rural areas [i.e. mean pH of 4.4 for Ban sur Meurthe (no. 7)] and lower in the urban areas [mean pH of 5.0 for Strasbourg (no. 1) and pH of 5.7 for Colmar (no. 2)]. This is probably due to the presence of CaCO 3 in the “loess”, which is the major constituent of soils in the upper Rhine valley. The relationship between the chemical composition of rain andair-mass trajectories for four humid weeks which presented only one rain event are also examined.

The uptake of nitryl chloride ClNO2 by pure water and NaI solutions was studied as a function of temperature in the range from 268 to 279 K with the droplet train technique. An upper limit of 10−5 was derived for the uptake on pure water, while the uptake rate was observed to be greatly enhanced in the presence of 10−3–10−2 M iodide, yielding uptake coefficients in the range from 1.1 × 10−3 to 6.6 × 10−3. This enhancement is a consequence of a reaction between I− and ClNO2 where we suggest that a transfer of Cl+ to iodide is involved. We also suggest that bulk kinetics alone is unable to describe the measured uptake rate which is influenced by surface reactions. These results show that heterogeneous chemistry in concentrated aerosols may play an important role for the fate of ClNO2, and may affect the concentration of atomic chlorine in the marine boundary layer.

Using the droplet train technique, the uptake of N{sub 2}O{sub 5} by NaCl solution and pure water was studied as a function of temperature in the 262-278 K range. The N{sub 2}O{sub 5} uptake coefficients on pure water decrease from 0.03 to 0.013 with increasing temperature. With the NaCl solution, there was a lower nitrate yield, indicating that nitrogen compounds are formed after the N{sub 2}O{sub 5} uptake by reactions with NaCl. The NaCl uptake coefficient is greater than pure water, so N{sub 2}O{sub 5} may be reaction-controlled. 38 refs., 7 figs., 1 tab.

Hydroxy-pinonaldehyde and hydroxy-pinonic acid, monoterpene degradation products have been for the first time isolated by synthesis and fully characterized. The key step of the synthesis is an oxidation using the RuCl 3 /NaIO 4 system.

This chapter describes the different phases of aircraft wake formation and the various physical and chemical processes that occur. Particulate matter generation is treated with special attention, especially in the near field of aircraft, with regard to the potential impact on climate change, for example, through contrail formation. Keywords: wake vortex; aerosols; nucleation; microphysics; chemistry

A filter-XAD-2 resin plug high-volume air sampler was used to collect particulate (P) and gaseous (G) phases of seven pesticides (atrazine, terbuthylazine, alachlor, metolachlor, cymoxanil, diflufenicanil, and fenoxaprop- p -ethyl) and two metabolites (de-ethylatrazine (DEA) and de-ethylterbuthylazine (DET)) in downtown Strasbourg (France). Most of the molecules listed above were found to be associated only with particulate aerosols and only four of them were detected regularly in both atmospheric phases (particulate and gaseous). The results presented in this work showed that models developed previously to describe the gas/particle (G/P) partitioning did not work for currently used pesticides. A new partition equation ( K org , m 3 ng −1 ) was defined for the pesticides under study using environmental parameters such as temperature, relative humidity, and organic carbon content of atmospheric aerosols.

Both UV–visible absorption spectrum and Henry's law constants H of S-ethyl dipropylthiocarbamate (EPTC) were investigated in this work. Absolute values of molar absorptivity coefficients ɛ of EPTC in methanol were determined using a deuterium lamp over the wavelength range 233–343 nm at room temperature (298 ± 2 K). Absorbances were also measured at 253.7 nm using an Hg-lamp in the concentration range 10–426 mg L−1. The absolute value of ɛ at this wavelength, ɛ = 45 ± 4 M−1 cm−1, was then determined according to the Beer–Lambert's law. The quoted error corresponds to 2σ obtained from the least square fit analysis and includes an estimated systematic error of 5% due to the uncertainties in aqueous concentrations. The absorbances measured were lower than 1.2 and did not exhibit any deviation from the Beer–Lambert's law. Henry's law constants H of EPTC were determined over the temperature range 278–293 K with a dynamic system based on the existence of an equilibrium at the water/air interface within the length of a microporous tube. The obtained data were used to derive the following Van't Hoff expression: ln H = (9134 ± 1180)/T − (26.6 ± 3.9) leading to a mean value of 91 ± 22 M atm−1 at 293 K. The quoted errors are given at 2σ level from the least-squares analysis and include the estimated systematic error of 5%. It is shown that, at a cumulus cloud temperature of 283 K, the fraction of EPTC in the atmospheric aqueous phase is negligible and therefore this compound will be mainly present in the gas phase.

In to order increase sensitivity and to reduce the background induced by matrix effects, a method was developed that uses flash chromatography to separate various compounds present in atmospheric aerosol samples prior to their analysis with different analytical techniques (GC-MS, GC-FID, HPLC). For this purpose, flash chromatography using a 4 g silica gel column crossed by eluent at a flow rate of 20 mL min(-1) was used. An eluent with enhanced polarity is needed to separate nonpolar (linear and branched alkanes), semipolar (PAH, nitro-PAH and cholesterol) and polar (methoxyphenols, alkanoic acids, and levoglucosan) compounds. Three combinations of solvents were used: hexane for the nonpolar fraction (F1), toluene/hexane for the semipolar fraction (F2) and dimethylformamide for the polar fraction (F3). The use of different eluents for each fraction allows separation of the sample to be accomplished with good repeatability and satisfying yields [85 +/- 5% for F1, 81 +/- 8% (PAHs), 89 +/- 6% (nitro-PAHs) and 74 +/- 7% (cholesterol) for F2 and 79 +/- 7% (n-alkanoic acids), 40 +/- 11% (methoxyphenols) and 77 +/- 6% (levoglucosan) for F3]. The methoxyphenol yields were low due to losses during the concentration/evaporation step. This method was then applied to analyse the organic composition of particles collected at an urban site in Strasbourg (France).

Current-used pesticides commonly applied in Alsace region (Eastern France) on diverse crops (maize, vineyard, vegetables, etc.) were analysed, together with Lindane, in rainwater between January 2002 and June 2003 simultaneously on two sites situated in a typical rural (Erstein, France) and urban area (Strasbourg, France). Rainwater samples were collected on a weekly basis by using two automatic wet only collectors associated with an open collector for the measurement of rainwater height. Pesticides were analysed by GC-MSMS and extracted from rainwater by SPME. Two runs were performed. The first one was performed by using a PDMS (100 μm) fibre for pesticides where direct injection into GC is possible (alachlor, atrazine, azinphos-ethyl, azinphos-methyl, captan, chlorfenvinphos, dichlorvos, diflufenican, α- and β-endosulfan, iprodione, lindane, metolachlor, mevinphos, parathion-methyl, phosalone, phosmet, tebuconazole, triadimefon and trifluralin). The second run was performed by using PDMS/DVB fibre and this run concerns pesticides where a preliminary derivatisation step with pentafluorobenzylbromide (PFBBr) is required for very low volatiles (bromoxynil,2,4-MCPA, MCPP and 2,4-D) or thermo labiles (chlorotoluron, diuron and isoproturon) pesticides. Results showed that the more concentrated pesticides detected were those used as herbicides in large quantities in Alsace region for maize crops (alachlor, metolachlor and atrazine). Maximum concentrations for these herbicides have been measured during intensive applications periods on maize crops following by rapid decrease immediately after use. For Alachlor, most important peaks have been observed between 21 and 28 April 2003 (3327 ng L−1 at Erstein and 5590 ng L−1 at Strasbourg). This is also the case for Metolachlor where most important peak was observed during the same week. Concentrations of pesticides measured out of application periods were very low for many pesticides and some others where never detected during this period. This is the case for diflufenican which was detected only during application. Two important peaks of concentrations were observed; a first one (101 ng L−1) in Erstein in November 2002 (4–11 November) and a second one (762 ng L−1) also in Erstein (28 April–15 May). The same behaviour can be seen for chlorfenvinphos and phosalone which have been detected, respectively, 2 and 4 times in Erstein and Strasbourg at high concentrations (28 April 2003–15 May 2003, 187 ng L−1 of phosalone and 157 ng L−1 of chlorfenvinphos in Erstein). MCPP, 2,4 MCPA and 2,4-D have been detected at high concentrations in rainwater but for the other pesticides very episodically and mainly during their use in agriculture. Maximal concentrations of MCPP and 2,4 MCPA have been measured in Erstein between 28 April and 15 May (904 and 746 ng L−1, respectively). Comparison between rural and urban sites showed that concentrations in rural areas are generally higher except for pesticides commonly applied in urban areas like Diuron. No seasonal phenomenon was observed for Diuron. This herbicide has been detected in practically all of the rainwater samples in Strasbourg (40/41) with a maximum of 1025 ng L−1 (16–23 September 2002) in 38 samples on 41 in Erstein with a maximum of 317 ng L−1 (15–23 October 2002). The total concentration of Diuron measured between 4 March 2002 and 20 July 2003 is of 4721 ng L−1 in Strasbourg and 5025 ng L−1 in Erstein. This result shows that wet deposition of Diuron in urban and rural sites was equivalent and can be explained by the “urban use” of this molecule together with its potential persistence.

By using a dynamic dilution system, the atmospheric measurement of 11 selected toxics VOCs (ethylene, acetylene, propene, 1-butene, 1,3-butadiene, 1-pentene, 1-hexene, benzene, toluene, ethylbenzene, m+p-xylene) from the list WHO of 1996 and TO-14 method of US EPA by preconcentration by thermal desorption (TD), analysis by gas chromatography (GC), identification and quantification with a flame ionisation detector (FID) was developed and validated in term of metrology, especially the techniques of sampling of these VOCs with adsorbents cartridges “Air Toxics” when used with an “UMEG sampler” equipped in the inlet with a nafion® membrane. In particular the influence of climatic conditions (temperature and relative humidity) and the influence of chemical factors like ozone, on the representativity of sampling were studied. Experiments made with various humidities showed that the addition of a nafion® membrane in the inlet of the sampling system was required. Without this membrane, losses of compounds were observed for RH >50%. With this membrane, storage for 2 weeks in a refrigerator, as for canisters, did not induce a loss of compounds. No significative decrease of concentrations of the studied VOCs after 14 days storage, which are known to react with ozone, were observed with an ozone concentrations of 55 ppb. One explanation is that nafion® membrane, placed in the inlet of the sampler, will neutralize ozone before entering the sampling tubes. This observation is in accordance with literature which states that the sampling of VOCs on Carbotrap cartridges without ozone scrubber induce a loss of compounds.

Solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry has been used for analysis of four phenols and sixteen nitrophenols in rainwater samples. Analytes were extracted from the water in the immersion mode and derivatised for 5 min during direct desorption in the GC injector. Before desorption, 2 microL N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MDBSTFA) was introduced into the injector, which was maintained at 280 degrees C. Different conditions affecting extraction efficiency were studied, including temperature, type of microextraction fibre, and effect of pH and ionic strength. Five different fibre coatings were tested: 85-mum polyacrylate (PA), 100-microm polydimethylsiloxane (PDMS), 65-mum Carbowax-divinylbenzene (CW-DVB), 75-microm Carboxen-polydimethylsiloxane (CAR-PDMS), and 65-microm polydimethylsiloxane-divinylbenzene (PDMS-DVB). The best conditions were use of PA fibres for 40 min at ambient temperature (75 g NaCl per 100 mL, pH 3.0). MDBSTFA was used as derivatising agent because it enables analysis of phenols derivatives with high confidence in identification, because in electron-impact mode TBDMS-phenol derivatives produce the specific M-57 ion. Quantification was achieved by using 4-nitrophenol-d4, at 1 mg L(-1), as internal standard. Linearity was good, with correlation coefficients in the range 0.9888 (o-cresol) to 0.9987 (dinitro-o-cresol, DNOC). Detection limits varied between 0.208 and 99.3 microg L(-1) and quantification limits between 0.693 and 331 microg L(-1). Uncertainties varied between 8.7% (phenol) and 17.9% (4-methyl-2-nitrophenol). The method was successfully applied to the analysis of rainwater collected at urban and rural sites in Alsace (East of France). Because of derivatisation in the injector and the associated high temperature, the lifetime of the fibre is severely reduced.

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Atmospheric samples were collected in an urban area (Strasbourg centre) in spring/summer 2004, in order to determine the concentrations of different pesticides in the gaseous and particulate phases and to compare the efficiencies of different adsorbents at trapping the gaseous phase. Two high-volume samplers were placed next to each other in the botanical garden in the centre of Strasbourg. Air sampling was carried out using a glass fibre filter and different adsorbents for 48 hrs. The following adsorbents and combinations of adsorbents were compared: XAD-2 with PUF, XAD4 with PUF, XAD-2 with a PUF-XAD2-PUF sandwich, PUF with a PUF-XAD4-PUF sandwich. In order of efficiency at trapping pesticides, the "sandwiches" are the most efficient, followed by XAD-2 and XAD-4 resins. However, although the "sandwiches" are slightly better at trapping than XAD-2, the use of XAD-2 is recommended for technical reasons. The PUFs are the least efficient at trapping. Among the 27 pesticides analysed, trifluralin, alachlor, metolachlor and captan were the most concentrated pesticides, followed by lindane, alpha-endosulfan and diflufenican. This result is in accordance with farming activity in the Alsace region, where the pesticides that are used on large crops (maize, cereals) are applied in the greatest quantities. Vineyards are another important form of agriculture in Alsace, but the quantities of pesticides applied in comparison to those used on large crops is very low, which explains the low detection of vineyard pesticides in air samples observed here. The concentrations are depend on the identities and properties of the pesticides analysed, but on the whole they remain rather low. It is important to perform measurements like these in the urban environment, as these compounds can be harmful to human health and the environment and so their concentrations need to be monitored.

Atmospheric sampling (gas and particles) of 5 phenols (phenol, m-cresol, p-cresol, o-cresol, pentachlorophenol) and 15 nitrophenols (3-methyl-2-nitrophenol, 3-nitrophenol, 4-methyl-2-nitrophenol, 5-methyl-2-nitrophenol, 2-methyl-3-nitrophenol, 3-methyl-4-nitrophenol, 2,6-dinitrophenol, bromoxynil, 2,5-dinitrophenol, 2,6-dinitropcresol, 2,4-dinitrophenol, ioxynil, DNOC, 3,4-dinitrophenol, dinoseb) on XAD-2 resin (20 gr) and glass fibre filters, respectively, were performed in 2002 by using 'Digitel DA80' high volume sampiers. These measurements were undertaken in order to show spatial and geographical variations of concentrations and the role of traffic in the emissions of these compounds to the atmosphere.Sampling were performed in Strasbourg (eastern France), in its vicinity (Schiltigheim) and in Erstein. Sites were chosen to be representative of urban (Strasbourg), suburban (Schiltigheim) and rural (Erstein) conditions. Field campaigns were undertaken simultaneously in urban and suburban sites during all the seasons during 4 hours at a flow rate of 60 m3 h(-1), which gives a total of 240 m3 of air per sample. Period of sampling varied between 06h00 to 10h00, 11h00 to 15h00 and 18h00 to 22h00 in order to evaluate a variation of concentration during automobile traffic between urban, suburban and rural areas. Gas and particle samples were separately Soxhlet extracted for 12 h with a mixture of CH2Cl2 / n-hexane (50:50 v/v), concentrated to about 1 mL with a rotary evaporated and finally dried under nitrogen. Dry extracts were dissolved in 1 mL of CH3CN. Before analysis, extracts were sylilated by using MTBSTFA. Analysis was performed by GC/MSD in the SIM mode.Partitioning of phenolic compounds between gas and particle phases seems to be mainly correlated with vapour pressure. Among phenolic compounds analysed, phenol, p-cresol, pentachlorophenol and 2.4-dinitrophenol were detected in all samples and emissions from traffic seems to be the major source for the presence of these compounds to the atmosphere. No increase of concentrations in autumn tend to confirm this hypothesis since, with the use of domestic heating in colder months, increases of PAHs concentrations were observed and these compounds are known to be emitted by all combustion processes, Pentachlorophenol is a special case since this molecule is only used as wood preservative. Its presence in all atmospheric samples, whatever the locations and the period of time is the consequence of its persistence.These measurements demonstrate that phenols and nitrophenols are emitted to the atmosphere and further measurements, in order to confirm their sources, their behaviour and their potential impact to the air quality and to human health should be undertaken especially since the literature collected is relatively old. Concentrations of pentachlorophenol measured are very low and, due to its toxicity, further investigations should be undertaken.