UV-filters and musks fragrances have come into focus because these compounds are increasingly used in sunscreen products and in many products of daily use, such as cosmetics, skin creams, plastics or varnish. These compounds have gained increasing interest due to their occurrence in the environment and to their potential to cause endocrine disruption. UV-filters have been reported in coastal regions mainly due to recreational bathing activities, including both sea water (Sankoda et al. 2015) and marine mussels (Bachelot et al. 2012). The highest concentrations of UV filters in mussels were reported for two substances, ethylhexylmethoxycinnamate (EHMC) and octocrylene (OC) and occurred in sites with a strong touristic frequentation and a geomorphological conformation of the beach closed to the wide. In this context, the objectives of this work were three folds: firstly, a monitoring of the seasonal variations and diurnal trends of these emerging contaminants was conducted during the touristic period. Secondly, the relation between the concentration in water and in mussels was studied within one day for a better understanding of the temporal trends. Finally, the contribution of WWTP releases on coastal contamination was investigated. The extraction of mussel tissues was based on a QuEChERS procedure (Picot-Groz et al. 2014). Sea water was extracted with semi-preparative extraction (SPE) method. Analysis was performed with liquid chromatography coupled to high resolution mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS/MS). The developed analytical method allowed to detect target compounds at low levels under 10 ng/g in marine mussels and under 1 ng/L in sea water samples. A seasonal variation of OC and EHMC was observed with the highest concentration in mussels reported in July while the strongest touristic pressure. 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 a metabolism ability for these substances. This is in accordance with previous findings where mussels feed with contaminated phytoplankton bioaccumulated low UV-filter concentration (Gomez et al. 2012). One UV stabilizer (UVP) and one musk (galaxolide) occurred in mussels from a non protected area, indicating other inputs than bathing. The reason evoked is the arrival of WWTP rejects that do not allow a complete elimination of these compounds.