Perfluoroalkyl acids in fish of Italian deep lakes: Environmental and human risk assessment.

Determination of 20 PFASs in a fish species (Alosa agone) of commercial interest has been carried out in five Italian subalpine lakes to assess the risk for humans and predators for fish consumption. PFOS still presents the highest concentrations (0.9-16.6nggww) among the analysed PFASs, in spite of its normative restrictions. PFOS concentrations measured in all lakes, except in Lake Maggiore, are homogeneous with an average of 3.1±1.9nggww, which could be considered the "anthropogenic background concentration" of PFOS in fish of lakes located in an industrialised and urbanised region but without point sources. In Lake Maggiore, fish concentrations always exceed the EU EQS (9.1nggww) based on human fish consumption. Considering the effective consumption of fish in this area, an actual risk for fish consumption by humans is not evidenced, while a moderate risk of secondary poisoning for predators is highlighted. PFOA has been detected in significant concentration only in one sample in Lake Maggiore, while long chain PFCAs have been detected without significant differences among the lakes (0.3 to 2.7nggww). The present study demonstrates that biota monitoring of fish can be used as a valuable tool to classify the quality status of water bodies regarding bioaccumulative PFAAs, even if the water concentrations are close to the reachable detection limits.