An Integrated Assessment of PFAS: Source Tracing, Exposure Characteristics, and Health Risks in a Contaminated Area

PFASs have recently gained global concern as emerging contaminants due to their persistence, bioaccumulation potential, and potential health risks, making them a key research subject. The objectives of this study were to identify the primary sources of PFAS across multiple environmental media in the region, evaluate human exposure levels via multiple pathways, and quantify the associated carcinogenic and non-carcinogenic health risks. Source apportionment was carried out via correlation analysis, cluster analysis, ratio methods, Principal Component Analysis (PCA), and Positive Matrix Factorization (PMF). Exposure was modeled by estimating intake through two oral pathways: dietary ingestion and drinking water. Health risks were assessed using Monte Carlo simulation. The study found that PFAS contamination in the local tap water exhibited a complex pattern, reflecting contributions from both point sources and diffuse sources. Correlation and cluster analyses indicate that pollution sources within the investigated area are relatively concentrated. Widespread positive correlations exist among various PFAS, and the region is simultaneously influenced by local domestic non-point sources, traditional industrial point sources, alternative industrial point sources, and regional atmospheric transport. This constitutes a typical complex pollution zone characterized by coexisting multiple source inputs and intermingling legacy and emerging pollutants. Principal Component Analysis (PCA) and the Positive Matrix Factorization (PMF) receptor model were used to trace the complete pathway of PFAS from source emission and environmental migration to potential exposure routes. The results also indicate that the characteristics of environmental pollution and source contributions are associated with the type of environmental medium. The health risk assessment indicated that the non-carcinogenic risks of PFOA and PFOS, as well as the carcinogenic risk of PFOA, were at unacceptable levels, which require special attention. It is noteworthy that most of the non-carcinogenic and carcinogenic risks from oral ingestion showed significant differences between age groups. These results provide a scientific basis for controlling PFAS pollution and managing risks in the region, and demonstrate the utility of receptor models for source apportionment of complex environmental contaminants.