Perfluoroalkyl and polyfluoroalkyl substances

PFAS

Persistent organic compounds in which the hydrogen atoms at the carbon skeleton are completely (perfluoroalkyl) or partially (polyfluoroalkyl) substituted by fluorine atoms.

Per- and polyfluoroalkyl substances (PFAS) are organofluorine compounds in which the C-H bonds are completely (perfluoroalkyl) or partially (polyfluoroalkyl) replaced by C-F bonds.  PFAS belong to the chemical group of per- and polyfluorinated compounds (PFC).
PFAS encompass, for example, the gaseous fluorinated hydrocarbons used as coolants and propellants, and the fluorosurfactants, surface active compounds like the perfluorooctanoic acid (PFOA) and the perfluorooctanesulfonic acid (PFOS). Another group of PFAS are plastics like polytetrafluoroethylene (PTFE) which is well known from products with trade names like Teflon®, Scotchgard™, and Goretex®.

PFAS are widely used because of their unique chemical properties: many of them are heat resistant, lipophobic (fat repelling) and hydrophobic (water repelling). They are applied for instance in textile and leather impregnation, coatings, surface treatment of household articles and building materials, paper and packaging, industrial and household cleaning products, fire-fighting foams, hydraulic fluids and wire coatings. Further applications include those in metallurgy, electronics and medical technology.
During production and use PFAS may enter the environment. Because of the stable C-F bonds they are extremely persistent  and may spread in the environment reaching even remote places. Some of them are highly bioaccumulative and can biomagnify in the food web. Moreover, some PFAS are toxic or suspected to be carcinogenic.

Because of these unfavourable properties, the primary producer 3M has declared a voluntarily phase-out of the production of PFOS by 2001. Since 2006, the use of PFOS is restricted in the European Union (EU). In 2009, PFOS and its salts as well as perfluorooctanesulfonyl fluoride (PFOSF) were included in Annex B of the Stockholm Convention (restriction of production and usage). For PFOA the evaluation is still going on.

Substances

Perfluorobutanoic acid Fluorocarbon with 4 C-atoms
Perfluoropentanoic acid Fluorocarbon with 5 C-atoms
Perfluorohexanoic acid Fluorocarbon with 6 C-atoms
Perfluoroheptanoic acid Fluorocarbon with 7 C-atoms
Perfluorooctanoic acid Fluorocarbon with 8 C-atoms
Perfluorononanoic acid Fluorocarbon with 9 C-atoms
Perfluorodecanoic acid Fluorocarbon with 10 C-atoms
Perfluoroundecanoic acid Fluorocarbon with 11 C-atoms
Perfluorododecanoic acid Fluorocarbon with 12 C-atoms
Perfluorotridecanoic acid Fluorocarbon with 13 C-atoms
Perfluorotetradecanoic acid Fluorocarbon with 14 C-atoms
Perfluorobutanesulfonic acid Fluorocarbon with 4 C-atoms and one sulfonic acid group; substitute for PFOS in many applications
Perfluorohexanesulfonate Fluorocarbon with 6 C-atoms and one sulfonic acid group
Perfluoroheptanesulfonic acid Fluorocarbon with 7 C-atoms and one sulfonic acid group
Perfluorooctanesulfonic acid Fluorocarbon with 8 C-atoms and one sulfonic acid group
Perfluorodecanesulfonic acid Fluorocarbon with 10 C-atoms and one sulfonic acid group
Perfluorooctanesulfonamide Fluorocarbon with 8 C-atoms and one sulfonamide group

Specimen

Bream Bioindicator in rivers and lakes
Eelpout As the only viviparous fish in German nearshore waters, it is a bioindicator in nearshore coastal marine ecosystems.
Herring gull Inshore, the herring gull mainly feeds from the sea: upon fish, mussels, and crabs.
Roe deer, one-year-old The roe deer is the most common of the larger herbivores (first order-consumer) to be found in the wild in Europe.
Students Student groups with an even number of female and male students at the age of 20 to 29.

Sampling area

BR/NP Berchtesgaden The only high mountains national park in Germany and an area of the Limestone Alps with international relevance
Saarländischer Verdichtungsraum Important, old-industrialised conurbation in Germany.
Bornhöveder Seengebiet Main water divide between the North- and Baltic Sea
Rhein Longest river in Germany
NP Bayerischer Wald Germany's first national park
NP Vorpommersche Boddenlandschaft National Park in the largest brackish water (Bodden) habitat of the world.
BR/NP Wattenmeere National park in the world largest connected sand and mud flats.
Elbe Fourth largest river basin in Central Europe
Verdichtungsraum Halle-Leipzig Region in the chemical triangle of Central Germany
NP Harz Germany's largest forest national park
Solling Second highest and largest low mountain range in Northern Germany
BR Pfälzerwald Germany's largest connected forest area in a range of low mountains
Oberbayerisches Tertiärhügelland The Upper Bavarian Tertiary Uplands are a part of the Southern German Molasse Basin
Donau Second largest river in Europe
Sampling sites (humans) 4 university cities as sampling areas.

Sampling period

1982 - 2016

Extended information

Links to external information and legislation

Literature