A flower-shaped recycled polymeric-coated cellulose paper for the isolation of organic contaminants from waters

Polymeric waste, often discarded from everyday activities, poses environmental risks. An eco-sustainable thin-film microextraction approach (TFME) utilizing flower-like filter paper coated with waste polymers as the sorptive phase is presented herein for isolating volatile organic compounds (VOCs) from water samples. This particular phase configuration allows an efficient stirring with minimal resource consumption. The sorptive phase is prepared by dip-coating, which offers simplicity and enables simple polymer reusability. Low-density polyethylene (LDPE) and expanded polystyrene (PS) residues were evaluated as polymeric coatings, the latter providing a more efficient isolation of the analytes in shorter times. The effect of the main variables involved in the synthesis (paper size, polymer selection, concentration of the polymeric precursor, and the number of dips) and extraction process (extraction and elution parameters) was thoroughly evaluated. Working under the optimum conditions and using gas chromatography-mass spectrometry (GC-MS) as the instrumental technique, quantification limits in the range of 9-10 µg L^-1 were obtained for toluene, o- and p-xylene, ethylbenzene and styrene. Intra-day and inter-day precision (expressed as relative standard deviation) better than 7.6 %, and accuracy (expressed as relative recoveries) in the 92-110 % range were also obtained. The developed method was applied successfully to varied drinking water samples, revealing pollutants across diverse packaging materials. In tap waters, laboratory levels of styrene were noted (18 ± 3 µg L^-1). Mineral water in biobased cartons exhibited styrene, toluene (15.2 ± 0.3 µg L^-1), o-xylene (5.5 ± 0.2 µg L^-1), along with detected styrene and toluene in polyethylene terephthalate (PET) bottles.