Evaluating the role of biomass in the sorption of four UV-Filters

The presence of ultraviolet filters (UV) in personal and care products, like cosmetics or sunscreens, is quite common. Consequently, they have been found most of water systems (e.g. ocean, river, aquifers). In porous media, the two main processes governing their fate are sorption and degradation. In the case of degradation, it is mainly governed by co-metabolism processes, which means that these molecules are broken due to the presence of more labile organic carbon which facilitate an enzymatic activity in the system. On the other hand, most of UVs are characterized by high . Thus, sorption plays a central role in their fate. In dynamic biological systems, like hyporheic zones, bioremediation sites or Managed Aquifer Recharge facilities, a high amount of microorganisms, forming biofilms, can be found. In this work, we have evaluated the role of biomass as a sorbent of UV-filters. Furthermore, we have also evaluated the importance of redox conditions in the co-metabolic degradation, and thus, the production of biomass. To achieve this general objective, a conceptual and a numerical model were developed. The results of the models were compared with previous published data by Liu et al. (2013), which performed a set of batch experiments to evaluate the fate of UV under different redox conditions. The compounds evaluated were common UV filters: Benzophenone-3, the benzotriazoles (UV-326 and UV-329)), octyl 4-methoxycinnamatte and octocrylene.