Book of Abstracts. 1st TwiNSol-CECs Workshop gather scientific abstracts from scientists and experts interested in, but not limited to, problems of contaminants of emerging concern (CECs) occurrence in the environment and relevant analytical methods, as well as novel solutions for their removal. The content of Book of Abstracts will also go beyond these topics as it will serve as a forum for exchange of project ideas and results in the domain of environmental protection, contributing to the harmonization of research and innovation efforts important for the sustainable transition of whole Europe, as foreseen by the European Green Deal, towards zeropollution, i.e. toxic free environment.