Book excerpt: This Tema Nord report presents a study based on open information and custom market research to review the most common perfluorinated substances (PFC) with less focus on PFOS and PFOA. The study includes three major parts:1) Identification of relevant per-and polyfluorinated substances and their use in various industrial sectors in the Nordic market by interviews with major players and database information; 2) Emissions to and occurence in the Nordic environment of the substances described in 1); 3) A summary of knowledge of the toxic effects on humans and the environment of substances prioritized in 2); There is a lack of physical chemical data, analystical reference substances, human and environmental occurrence and toxicology data, as well as market information regarding PFCs other than PFOA and PFOS and the current legislation cannot enforce disclosure of specific PFC substance information.