Perfluorinated Alkylated Substances (PFASs)    

Want to know a little more about PFASs?

  • They are man-made chemicals that have been utilized for many industrial and commercial purposes since the 1950s, including use in textiles, food packaging, and aqueous film-forming foams (used to extinguish fires).
  • The chemical characteristics that make them useful in manufacturing include:
    • The high bond strength between the many carbon – fluorine bonds they contain
    • Their ability to hate water (hydrophobic) and love lipids (hydrophilic)
    • Their high thermal stability, meaning they can withstand high temperatures
  • Some PFASs are identified as toxic, persistent, and bioaccumulative (build up in the tissues of organisms).
  • Due to their usage, PFASs are found in ecosystems around the world and have been observed to impact organismal behavior and health.

The EPA has more information regarding the USA’s regulation of PFASs here:

Routes of environmental exposure of PFASs

Routes of environmental exposure of PFASs.
Source: Sunderland et al., 2019.

What is PFOS?

  • Perfluorooctane sulfonate is a chemical in the PFAS chemical group.
  • It is a persistent organic pollutant (POP) which means it is listed on the POP list of the Stockholm Convention and is encouraged to be regulated and phased out due to its toxicity and persistence.
  • It is one of the most frequently detected PFASs in the environment.


Source: Huang et al., 2019 (DOI 10.1016/j.toxrep.2019.06.016)


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