Department Environmental Chemistry

Conventional wastewater treatment has limited effectiveness in removing per­fluoro­­­alkyl and polyfluoroalkyl substances (PFAS) from aqueous waste streams, and therefore WWTPs act as most relevant point sources to the aquatic environment.

The occurrence and levels of perfluoroalkyl acids (PFAAs) emitted from specific pollution sources into the aquatic environment in Switzerland were studied using digested sewage sludge from 45 WWTPs in catchments containing potential industrial emitters.

Elevated emissions were observed in catchments capturing discharges from metal plating industries, aqueous firefighting foams, and landfill leachates . Some elevated perfluoroalkyl carboxylic acids levels could be attributed to emissions from textile finishing industries. Although sewage sludge is a minor compartment for PFAAs, these investigations are helpful for the identification of hot-spots from industrial emitters.

Publication

Alder AC, van der Voet J. (2015). Occurrence and point source characterization of perfluoroalkyl acids in sewage sludge. Chemosphere 129, 62-73.  http://dx.doi.org/10.1016/j.chemosphere.2014.07.045