# Biodegradation and Bioaccumulation of organic chemicals

Degradation processes heavily determine the fate of chemicals in the environment. Degradations may be the result of abiotic reactions, such as photolysis or hydrolysis after direct interaction with sunlight and water, respectively, or may be operated by organisms (i.e. biotransformation). Slow biodegradability and/or biotransformation may be associated to long persistence in the environment, and in the biota and to bioaccumulation phenomena. In particular, the investigation of the potential effects due to the accumulation of substances in humans and animals has been a challenging topic in the last few decades. Biotransformation was highlighted in the 1980s as a determinant factor for the refinement of BAF related estimations in fish and continues to be indicated as a key element for bioaccumulation science. Furthermore, the assessment of biodegradability and bioaccumulation potential are required procedures under several regulatory frameworks, such as the REACH regulation.
The use of QSAR models is suggested as a cost effective solution to be adopted in the absence of experimental data, which can support and integrate hazard assessment procedures.
The QSAR research group in Environmental Chemistry and Ecotoxicology is actively involved in several studies and collaborations aimed at the development of in silico models for the prediction of Biodegradation, Bioaccumulation and Biotransformation of organic chemicals.
Recent studies have been focussed on the prediction of these properties for important classes of contaminants of emerging concern such as Fragrances materials and Pharmaceuticals.

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