International audienceUV-filters and musks fragrances have come into focus because these compoundsare increasingly used in sunscreen products and in many products of daily use,such as cosmetics, skin creams, plastics or varnish. These compounds have gainedincreasing interest due to their occurrence in the environment and to their potentialto cause endocrine disruption. UV-filters have been reported in coastal regionsmainly due to recreational bathing activities, including both sea water (Sankoda etal. 2015) and marine mussels (Bachelot et al. 2012). The highest concentrations ofUV filters in mussels were reported for two substances,ethylhexylmethoxycinnamate (EHMC) and octocrylene (OC) and occurred in siteswith a strong touristic frequentation and a geomorphological conformation of thebeach closed to the wide. In this context, the objectives of this work were threefolds: firstly, a monitoring of the seasonal variations and diurnal trends of theseemerging contaminants was conducted during the touristic period. Secondly, therelation between the concentration in water and in mussels was studied within oneday for a better understanding of the temporal trends. Finally, the contribution ofWWTP releases on coastal contamination was investigated. The extraction ofmussel tissues was based on a QuEChERS procedure (Picot-Groz et al. 2014). Seawater was extracted with semi-preparative extraction (SPE) method. Analysis wasperformed with liquid chromatography coupled to high resolution massspectrometry (LC-MS/MS) and gas chromatography-mass spectrometry(GC-MS/MS). The developed analytical method allowed to detect targetcompounds at low levels under 10 ng/g in marine mussels and under 1 ng/L in seawater samples. A seasonal variation of OC and EHMC was observed with thehighest concentration in mussels reported in July while the strongest touristicpressure. The diurnal trend of UV filters was similar in sea water and in mussels.These results suggest a high bioconcentration potential in mussels, and probably ametabolism ability for these substances. This is in accordance with previousfindings where mussels feed with contaminated phytoplankton bioaccumulatedlow UV-filter concentration (Gomez et al. 2012). One UV stabilizer (UVP) andone musk (galaxolide) occurred in mussels from a non protected area, indicatingother inputs than bathing. The reason evoked is the arrival of WWTP rejects thatdo not allow a complete elimination of these compounds
