LAUSR

Abstract Microplastics (MP) are an omnipresent marine contaminant. Mass related MP data facilitate interregional and/or temporal comparisons of MP loads in various environmental compartments. Pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) provided mass and type classification of MP for nine environmentally common polymers at trace levels. Applied to 17 commercial Atlantic and Mediterranean marine salt samples all targeted polymers were detected at least once. Polypropylene and poly(ethylene terephthalate) (both in 16 of the 17 samples), polyethylene (15/17), polystyrene (13/17) and poly(vinyl chloride) (7/17) were those most frequently found. Total MP content of Fleur de Sel (FdS) (138–1993 μg/kg) exceeded that of sea salt (14–60 μg/kg) considerably, due to different harvesting conditions. Disposable packaging and textile fibers are supposed to be the most prominent sources. Regional patterns of MP compositions are distinguished and enable mapping for further targeted source related studies. MP in FdS reflects the MP mass load of corresponding coastal waters and provides its temporal/spatial investigation.