The perfluorinated PFAS contamination threshold concentrations were established in Decree of the Ministry of the Environment of 6.07.2016 which transposes the Directive 2014/80 / EU [amendment Annex II of Directive 2006/118 / EC] on the protection of groundwater against pollution.
The CNR-IRSA in 2013 published the «Evaluation of environmental and health risks associated with the contamination of perfluoro-alkyl substances (PFAS)» on the state of contamination from PFAS in surface water bodies and drinking water for the Vicenza area. Threshold values for PFAS have been introduced to define the quality of groundwater, as defined by Parte IV, Titolo V, Allegato 5, Tabella 2.
Criteria of Values threshold of table 3 Decree of the Ministry of the Environment of 6.07.2016
- the extent of interactions between groundwater and associated aquatic ecosystems and terrestrial ecosystems that depend on them;
- interference with legitimate uses of groundwater, present or future;
- human toxicity, ecotoxicity, tendency to dispersion, persistence and their bioaccumulation potential.
Following Table 3 Threshold values for the assessment of the chemical status of the groundwater, which includes the five PFASs that follow:
- Perfluoro pentanoic acid (PFPeA) [3 µg/l]
- Perfluorohexanoic acid (PFHxA) [1 µg/l]
- Perfluorobutansulphonic acid(PFBS) [3 µg/l]
- Perfluorooctanoic acid (PFOA) [0,5 µg/l]
- Perfluorooctysulphonic acid (PFOS) [0,03 µg/l]
Not all PFAS are included in Table 3 of Decree 6.07.2016 and a cumulative threshold reference value is not indicated, and considering the possible presence in food and drinking water, l’EFSA [European Food Safety Authority]has established the maximum daily dose of PFOS [150 ng / kg body] and PFOA [1.5 ng / kg body], both long-chain alkyl perfluorinates.
It is useful to report the limits to water discharge imposed by Decree of the Veneto Region of the Director of the Area Protection and Development Area n. 5 of 22.07.2016 and the interesting ARPAV publication on Contamination from PFAS:
- Acid Perfluoro Ottan Sulphonate (PFOS) ≤ 0,03 µg/litro;
- Perfluoro Ottanoic Acid (PFOA) ≤ 0,5 µg/litro;
- Butanoic Perfluoro Acido (PFBA) ≤ 0,5 µg/litro;
- Acid Perfluoro Butan Sulfonato (PFBS) ≤ 0,5 µg/litro;
- Addition to other PFAS [Pentanoic Perfluoro Acid (PFPeA) + Nonanoic Perfluoro Acid (PFNA) + Decanoic Perfluoro Acid (PFDeA) + Esanoic Perfluoro Acid (PFHxA) + Heptanoic Perfluoro Acid (PFHpA) + Undecanoic Perfluoro Acid (PFUnA) + Perfluoro Esan Sulfonato ( PFHxS) + Dodecanoic Perfluoro Acid (PFDoA)] ≤ 0.5 μg / liter.
The presence of PFAS in the subsoil does not exclude the possibility of adopting the procedures provided for by Title V of Legislative Decree 152/2006 for:
- process a specificationrisk analysis (the only tool to define the possible contamination status of a site based on the destination)
- verify the eventual exceedance of the Risk Threshold Concentrations (CSR).