Identification and quantification of linear and branched isomers of perfluorooctanoic and perfluorooctane sulfonic acids in contaminated groundwater in the veneto region

tPerfluoroalkylated acids (PFAAs) are ubiquitous xenobiotic substances characterized by high persistency, bioaccumulation potential and toxicity. They have generated global concern because of their widespread presence both in water and biota compartments. In the past four years, alarming levels of these pollu-tants have been found in both surface and groundwater collected in an area covering more than 150square kilometers in the south-western part of the province of Vicenza (Veneto region, Italy). One of the sources of the contamination recognized by local authorities is a fluorochemicals production plant that produced PFAAs since late sixties by electrochemical fluorination involving the obtainment of a complex mixture of linear and branched isomers. Branched isomers account for a significant part of total long chain homologues (22%–35%). Because of the potential threat to public health and the absence of specific limits set for these pollutants by Directive 98/83/EC, local authorities have established the following performance limits for drinking water: 90 ng L−1for PFOA + PFOS, (reduced to 40 ng L−1in the most contaminated municipalities), 30 ng L−1for PFOS and 300 ng L−1for the sum of all other PFAAs.