Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals of environmental and human health concern due to their persistence, potential toxicities, and potential to bioaccumulate. Fluoropolymers, a subset of polymeric PFAS, consist of a carbon backbone that is fully or partially fluorinated. This structure confers unique properties such as chemical and thermal resistance, as well as hydrophobicity and lipophobicity and has led to diverse industrial and consumer applications of fluoropolymers. As such, these materials are positioned as a significant component of the global fluorochemical industry and economy.

However, fluoropolymer production has raised concerns due to the use, formation, and emission of various non-polymeric PFAS. In response, industry has sought to mitigate its impacts by introducing alternative PFAS, implementing emission abatement technologies, and modifying production processes.

This thesis aimed to determine and characterize PFAS emissions from fluoropolymer production plants (FPPs) in Europe and China by gaining a holistic understanding of production processes to identify sources and emission pathways. Emissions were captured through emission data collection (Paper I) and environmental sampling near FPPs (Papers II-IV) and further characterized through an emission inventory (Paper I), targeted analyses, suspect screening (Papers II-IV), and atmospheric dispersion modelling (Papers II and IV). Differences in management of PFAS emissions by FPPs between China and Europe were investigated by comparing measured atmospheric concentrations and assessing the implications for human exposure.

Results indicated that despite recent emission reduction efforts in the UK and the Netherlands, FPPs remain point sources of various PFAS, including introduced alternatives (Papers I-III). Perfluorooctanoic acid (PFOA), which was listed in the Stockholm Convention on Persistent Organic Pollutants in 2019, was still in use and emitted in large quantities during the sampling period in China in 2019 (Paper IV). Other identified emissions included monomeric PFAS, by-products from monomer production and polymerization, and PFAS used in fluoropolymer processing (Paper I). Furthermore, due to the persistence of PFAS, historical emissions have turned some production sites into contamination hotspots (Paper III).

Atmospheric dispersion modelling (Papers II and IV) showed that part of the atmospheric PFAS emissions could be subject to long-range atmospheric transport and contribute to PFAS loads in remote locations. Thus, PFAS emissions by FPPs not only influenced the local environment, but possibly had global impacts. Measured median concentrations of atmospheric PFAS (Papers II-IV) exceeded guidance values for exposure through inhalation 30 km from the FPP in China. Before the implementation of emission abatement systems, a similar situation could have existed in the Netherlands and the UK, due to emissions of PFOA and its replacements.

Overall, this thesis underscored the need for a broader scope in future research and regulatory efforts, extending beyond specific well-known PFAS to encompass other PFAS emissions by FPPs. Additionally, addressing geographical disparities in PFAS management is crucial for effective global solutions.