An Optimised Extraction Method of Fluoranthene from Microplastics using Accelerated Solvent Extraction

Microplastics (MPs) are a group of anthropogenic contaminants with a high persistence in the environment. In order to determine the ecotoxicological impact of microplastic (MP), it is necessary to understand the nature and extent of chemicals that travel a long distance with MPs in the sea. However, currently no harmonized analytical methods are available to extract MPs from the environmental matrix as well as to extract pollutants from MPs. Therefore, this paper proposes a reliable method to determine the mass of contaminants adsorbed onto MP using an accelerated solvent extractor (ASE). A series of batch experiments were carried out in the laboratory to charge fluoranthene, a 4-ring polycyclic aromatic hydrocarbons, onto plastic pellets made of three different polymers: polyethylene (PE), polystyrene (PS) and polypropylene (PP). Fluoranthene adsorbed on the pellets was extracted using an ASE 300 (Dionex, Idstein). First results showed that best ASE extraction conditions for PE were at 100° C (at 100 bar) for 5 minutes in two static cycles using isopropanol, leading to an extraction efficiency of approx. 70 - 80%. A similar extraction efficiency was determined for PS at 70°C at 100 bar for 5 minutes in two static cycles using isopropanol. The highest recovery rate of 110 -115% was obtained for PP under the ASE condition at 100°C at 100 bar in 1 static cycle using isopropanol. Further research is needed to extend the analysed toxic pollutants adsorbed onto MPs and to develop a standardised and globally applied methodological approach.