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Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental contaminants formed during incomplete combustion or pyrolysis of organic material. The reliable quantification of PAH in airborne samples is still difficult, costly, and time-consuming due to the use of offline techniques, including long sampling on filters/adsorbents, laboratory extraction, purification, and concentration steps before analysis. To tackle these drawbacks, this work focused on the development of a fully automatic gas chromatograph (GC) equipped with a flame ionization detector (FID) and a sample preconcentration unit (PC) for gas sampling. This instrument was validated under laboratory-controlled conditions in the range 0–10 ng for 18 PAH. The chromatographic separation was rather satisfactory except for two PAH pairs, which were quantified together. For all compounds, the peak areas increased perfectly with the gaseous PAH concentration (R2 > 0.98), without any significant memory effect between two consecutive analyses. Considering a gaseous sample volume of 1 L, the extrapolated limits of detections (LOD) were in the range 19.9–62.6 ng/m3, depending on the PAH. Its analytical performances were then compared to those of the offline reference UHPLC-fluorescence method, widely used for airborne PAH monitoring. This was also compared with the very few portable or continuously operating instruments.

Phosphates in high concentrations are harmful pollutants for the environment, and new and cheap solutions are currently needed for phosphate removal from polluted liquid media. Iron oxide nanoparticles show a promising capacity for removing phosphates from polluted media and can be easily separated from polluted media under an external magnetic field. However, they have to display a high surface area allowing high removal pollutant capacity while preserving their magnetic properties. In that context, the reproducible synthesis of magnetic iron oxide raspberry-shaped nanostructures (RSNs) by a modified polyol solvothermal method has been optimized, and the conditions to dope the latter with cobalt, zinc, and aluminum to improve the phosphate adsorption have been determined. These RSNs consist of oriented aggregates of iron oxide nanocrystals, providing a very high saturation magnetization and a superparamagnetic behavior that favor colloidal stability. Finally, the adsorption of phosphates as a function of pH, time, and phosphate concentration has been studied. The undoped and especially aluminum-doped RSNs were demonstrated to be very effective phosphate adsorbents, and they can be extracted from the media by applying a magnet.

The presence of polycyclic aromatic hydrocarbons (PAHs) and particulate matter (PM) in air is known to provoke deleterious effects on human health. This work focused on the monitoring of PM and PAHs in the air over four weeks in a peri-urban site in Strasbourg (France), using a three-stage cascade impactor and a particle analyser allowing PM1, PM2.5 and PM10 discrimination. Meteorological conditions were monitored to study their influence on the pollutant levels. The average PM10 concentration of the cascade impactor and particle analyser varied from 11.8 to 80.2 µg/m3 and 10.6 to 220.2 µg/m3, respectively. The PAH total concentration ranged in 1.1–7.6 ng/m3 and a predominance of 5- and 6-ring PAHs was observed. PAHs were also more abundant in finer particles (PM1). Specifically, identified PAHs are traffic tracers suggesting that vehicular emission was one of its main sources. Two pollution episodes, associated with either a Saharan dust wind episode or traffic pollution, were observed, and led to PM10 and PM2.5 surpassing the daily limit values established by the European Union despite the traffic limitations according to the COVID restrictions. The total PAH concentrations were the highest during these periods suggesting PAHs might be bound to and transported via dust particles.