Importance of Sewage Treatment Plants in the Presence of Perfluorinated Compounds in Spanish

IMPORTANCE OF SEWAGE TREATMENT PLANTS IN THE PRESENCE OF PERFLUORINATED COMPOUNDS IN SPANISH MEDITERRAN RIVER BASINS.

J. Campo 1*, A. Masiá 1, Y. Picó 1, M. Farré 2, D. Barceló 2, 3

1 Food and Environmental Safety Research Group, Faculty of Pharmacy, University of Valencia, Av. Vicent Andrés Estellés s/n. 46100, Burjassot, València, Spain.

* Author contact:

2Department of Environmental Chemistry (IDAEA-CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain

3Catalan Institute of Water Research, ICRA Catalan Institute for Water Research-ICRA, C/Emili Grahit, 101, Edifici H2O, Parc Científic i Tecnològic de la Universitat de Girona, E-17003 Girona, Spain

Sewage treatment plant (STP) effluents are currently recycled in agricultural irrigation, for municipal and industrial purposes, to recharge aquifers or it can be discharged into rivers or the sea. However, in addition to classical priority pollutants, these waters can be also contaminated with non-regulated so-called emerging contaminants, among which the presence of perfluorinated compounds (PFCs) is causing high environmental concern. PFCs are now considered as persistent, bio-accumulative and toxic, which make them a potential hazard to human health. This work presents the results of an extensive survey carried out in 2010 in some of the STPs of Ebro, Guadalquivir, Jucar and Llobregat rivers (Spain). A total of 21PFCs have been monitored. After selective extraction, influent, effluent and dehydrated sludge samples were analyzed by Liquid Chromatography coupled to tandem Mass Spectrometry, in order to calculate the removal efficiencies of PFCs in such STPs.

From 21 analytes screened, 15 were found in influent and 13 in effluent samples. In fact, the waste-waters of all STPs were contaminated with at least one PFC. The concentrations (ng L-1) of perfluorocarboxilic acids (PFA) (the largest family and consequently the most frequently detected) in influent and effluent samples were in the range 0.06 (PFNA, Guadalquivir) – 5600.00 (PFHxA, Guadalquivir) and 0.18 (PFNA, Guadalquivir) – 102.90 (PFDA, Jucar), respectively. Regarding the sludge samples, 10PFCs were detected, being the PFAs the most ubiquitous. Their minimum and maximum concentrations (ng L-1) were 0.27 (PFUdA, Ebro) and1790.25 (L-PFOS, Llobregat), respectively. Removal efficiencies showed that, in 2010, the elimination of PFAs ranged from -398% (PFBA, Guadalquivir) to 99% (PFHxA, Llobregat). All these data confirm that most of the PFCs are only partially eliminated during the secondary treatment, commonly used in Spanish STPs, suggesting that they can constitute a focal point of contamination to the rivers.

Acknowledgements:

This work has been supported by the Spanish Ministry of Economy and Competitiveness through the projectsSCARCE-CDS 2009-0065 and CGL 2011-29703-C02-02.