Occurrence of Per- and Polyfluoroalkyl Substances (PFAS) in Canadian House Dust

Per- and Polyfluoroalkyl Substances (PFAS) in the Environment
Poster Presentation

Prepared by X. Fan, W. He, I. Popescu, S. Ibrahim, S. Beauchemin, C. Kubwabo
Health Canada, AL: 2203 B, 251 Sir Frederick Banting Driveway, Ottawa, Ontario, K1A 0K9, Canada


Contact Information: [email protected]; (613)513-7103

ABSTRACT

Indoor house dust is commonly used to assess potential human exposure to dust-bound contaminants, including per- and polyfluoroalkyl substances (PFAS). PFAS are ubiquitous in the environment due to their extensive use in industrial applications and consumer products. Exposure to PFAS has been linked to health risks such as thyroid dysfunction, immune suppression, impaired fetal development, and diabetes.

This study aimed to develop a rapid and sensitive method for detecting 49 PFAS in indoor dust samples. Samples underwent solvent extraction with sonication, cleanup by solid-phase extraction (SPE), and analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The findings will provide statistically robust data to inform risk assessment of indoor PFAS exposure.

Preliminary results (n=48) showed that PFAS were detected in over 90% of samples including the following subgroups, with median concentrations (max in parentheses):
1. Phosphoric acid diesters (diPAPs) – 175 (5160) ng/g for 6:2diPAP, 163 (8560) ng/g for 6:2/8:2diPAP, 161 (4250) ng/g for 8:2diPAP, and 19 (310) ng/g for 10:2diPAP.
2. Perfluoroalkyl carboxylic acids (PFCAs) – 35 (200) ng/g for PFBA (C4), 6 (140) ng/g for PFPeA (C5), 39 (630) ng/g for PFHxA (C6), 27 (560) ng/g for PFHpA (C7), 108 (4240) ng/g for PFOA (C8), 13 (920) ng/g for PFNA (C9), 13 (560) ng/g for PFDA (C10), and 9 (230) ng/g for PFDoA (C11).
3. Perfluoroalkane sulfonic acids (PFSAs) – 2 (110) ng/g for PFBS (C4), 31 (13080) ng/g for PFHxS (C6), 93 (2620) ng/g for PFOS (C8), and 9 (680) ng/g for PFDS (C10).
4. Fluorotelomer sulfonates (FTS) – 8 (790) ng/g for 6:2FTS, 14 (5890) ng/g for 8:2FTS, and 15 (5170) ng/g for 10:2FTS.

The widely scattered levels of PFAS suggest diverse indoor sources and exposure potentials. These insights are crucial for understanding indoor PFAS distribution and risk mitigation strategies.