Poly- and perfluoroalkyl substances (PFAS) contamination of indoor air and dust: A review of the literature on concentrations and sources

Poly- and perfluoroalkyl substances (PFAS) are composed of thousands of compounds. Although PFAS are ubiquitous, they are usually bioaccumulative and toxic. In recent studies, scholars have highlighted the significant presence of a large variety of PFAS in dust and air media in indoor environments. In light of the amount of time that people spend indoors and the associated presence of PFAS, contamination by indoor air or dust may represent important exposure pathways. Numerous PFAS have been detected on several continents at various concentrations and in different indoor environments, thus indicating that PFAS contamination is a worldwide problem. In this review, the reported concentrations of PFAS in the air and dust media in various indoor environments and the associated emission sources are summarized. FTOHs were detected mainly in the air samples, whereas PFCAs, PFSAs and FASA/FASEs were detected mostly in the dust samples. The air in stores appeared to be the most contaminated indoor environment, exhibiting the highest levels of FTOHs. Moreover, specific compounds, such as PFDcS, 6:2 FTS and 8:2 FTS, were reported in dust from offices, whereas dust from classrooms exhibited the highest average concentration of PFAS and the widest range of measured concentrations. Emission sources of PFAS in indoor environments were numerous and varied but remained poorly documented, thus making it difficult to clearly identify the sources of PFAS that were responsible for the observed air and dust contamination. Therefore, further investigations are needed to improve our understanding of the sources of contamination in indoor environments.