Wiktionary
perfluorononanoic acid
n. (context chemistry English) A synthetic perfluorinated carboxylic acid and fluorosurfactant that is also an environmental contaminant.
Wikipedia
Perfluorononanoic acid
Perfluorononanoic acid, or PFNA, is a synthetic perfluorinated carboxylic acid and fluorosurfactant that is also an environmental contaminant found in people and wildlife along with PFOS and PFOA.