PFDA is the acronym for perfluorononanoic acid. PFDA belongs to the per- and polyfluoroalkyl substances - PAFS - associated synthetic chemical alkyl compound. PFAs pose a significant problem to our environment and to our health. PFASs are found in biological samples of all kinds, including serum, skin and even hair. American scientists suspect that over 98% of the U.S. population has one or more detectable PFAS chemicals in their blood. Measurement results show that for the general population, inhalation of PFAS-contaminated indoor air and dust (from furnishings) are the main sources of exposure besides drinking water (Pitter G et al. 2020; Stubleski J et al. 2017). But also via fish, meat, milk, eggs and vegetables from contaminated regions.
For more, see below. PAFS and medicine