The method was based on an improved and more rapid Soxhlet extraction plus an improved, short and more efficient SPE technique for the 16 PAHs included in the US EPA priority pollutant list in airborne particles. Therefore, the aim of this paper is to optimise and validate a low-cost and rapid extraction methodology with low time and solvent consumption. Additionally, after extraction step, it needed purification steps by solid-phase extraction techniques like packed columns of silica, Florisil®, alumina or mixtures. An improved Soxhlet technique, called hot Soxhlet, heats the extractor body at lower temperature than the boiling point of solvents to keep it in the liquid state. Soxhlet extraction represents an inexpensive method for solid samples, nevertheless is rather time-consuming and requires high solvent consumption. However, these new techniques are expensive. In order to speed up sample preparation, new methodologies such as accelerated solvent extraction or microwave-assisted solvent extraction or ultrasound-assisted solvent extraction have been developed, saving processing time and solvent consumption. Traditional extraction procedures for PAHs involve many techniques, such as direct extraction with organic solvents, sonication and Soxhlet extraction. Determination of low levels of PAHs in complex matrices such as atmospheric particles leads to a search for accurate analytical methodologies, which need to be optimised and validated with recognized material references. In the atmospheric environment, PAH emissions are well known, as they originated from car exhausts, domestic combustion, industrial activities, agriculture activities and natural sources, such as biomass burning. Similar measures were taken by other European organizations. The European Commission exposed a wide toxicological guidance since the 2001 position paper to the Europe 2020 strategy. These hazardous hydrophobic organic compounds (HOCs) led international organisations to establish policies for the environment and indoor air. Due to holidays and / or possible strikes, delays can occur.Polycyclic aromatic hydrocarbons (PAHs) are lipophilic compounds with important carcinogenic risk. ![]() Please understand that we have no influence on the internal running and delivery times of the package services. Information for the calculation of the delivery date ![]() If your country is not in the list above, please do not hesitate to contact us. These will be paid by buyer directly at the import / receipt of the goods. We calculate shipping costs by shipping weight:ĭeliveries from China to worldwide, additional taxes or costs (customs duties, import turnover tax, etc.) could be added. You can track the progress of your shipment and also the planned delivery date. On the day of sending your goods, you will receive an automatic e-mail with your package number and a link for tracking the shipment. On Saturday and Sunday as well as Holidays no ordered goods will be dispatched. The order will be shipped in 2 or 3 working days. ![]() The delivery of uninsured packages is impossible. The goods will be shipped with tracking number as standard from China to Worldwide, the delivery time and the shipping costs depend on countries.
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