Perfluoroalkyl acids and their precursors in indoor air sampled in children's bedrooms
Kerstin Winkens1, Jani Koponen2, Jasmin Schuster3
1Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University, Stockholm, Sweden.
Insights
This study monitored per- and polyfluoroalkyl substances (PFASs) in Finnish children
Area of Science:
- Environmental Science
- Public Health
- Analytical Chemistry
Background:
- Per- and polyfluoroalkyl substances (PFASs) are widely used synthetic chemicals with potential health concerns.
- Indoor air is a significant exposure route for PFASs, particularly for vulnerable populations like children.
- Understanding PFAS contamination in children's bedrooms is crucial for assessing exposure and developing mitigation strategies.
Purpose of the Study:
- To investigate the contamination levels and patterns of 17 perfluoroalkyl acids (PFAAs) and 9 precursors in indoor air of children's bedrooms in Finland.
- To identify the most prevalent PFAS compounds and their sources within the indoor environment.
- To explore correlations between room characteristics and PFAS concentrations.
Main Methods:
- Comprehensive indoor air monitoring study involving 57 children's bedrooms in Finland.
- Analysis of 17 PFAAs and 9 PFAS precursors, including 6:2 fluorotelomer acrylate (6:2 FTAC) and 6:2 fluorotelomer methacrylate (6:2 FTMAC).
- Statistical analysis to identify correlations between PFAS concentrations and room characteristics.
Main Results:
- 8:2 fluorotelomer alcohol (8:2 FTOH) was the most frequently detected compound, with the highest median concentration (3570 pg/m³).
- While C8 PFAAs remain abundant, concentrations of some fluorotelomer substances of emerging concern (FOSCs) like 6:2 FTOH were higher than longer-chain variants.
- 6:2 FTMAC was frequently detected (58%) with high maximum concentrations (13,000 pg/m³), and higher EtFOSE levels were found in rooms with plastic flooring.
Conclusions:
- Indoor air PFAS levels exhibit a multi-year time lag in response to production changes, indicating persistent environmental contamination.
- Children's bedrooms can be significant reservoirs for various PFASs, including emerging precursors.
- Room characteristics, such as flooring type, can influence indoor PFAS concentrations, suggesting localized sources and exposure pathways.
Abstract:
The contamination levels and patterns of perfluoroalkyl acids (PFAAs) and their precursors in indoor air of children's bedrooms in Finland, Northern Europe, were investigated. Our study is among the most comprehensive indoor air monitoring studies (n = 57) and to our knowledge the first one to analyse air in children's bedrooms for PFASs (17 PFAAs and 9 precursors, including two acrylates, 6:2 FTAC and 6:2 FTMAC). The most frequently detected compound was 8:2 fluorotelomer alcohol (8:2 FTOH) with the highest median concentration (3570 pg/m3). FTOH concentrations were generally similar to previous studies, indicating that in 2014/2015 the impact of the industrial transition had been minor on FTOH levels in indoor air. However, in contrast to earlier studies (with one exception), median concentrations of 6:2 FTOH were higher than 10:2 FTOH. The C8 PFAAs are still the most abundant acids, even though they have now been phased out by major manufacturers. The mean concentrations of FOSE/As, especially MeFOSE (89.9 pg/m3), were at least an order of magnitude lower compared to previous studies. Collectively the comparison of FTOHs, PFAAs and FOSE/FOSAs with previous studies indicates that indoor air levels of PFASs display a time lag to changes in production of several years. This is the first indoor air study investigating 6:2 FTMAC, which was frequently detected (58%) and displayed some of the highest maximum concentrations (13 000 pg/m3). There were several statistically significant correlations between particular house and room characteristics and PFAS concentrations, most interestingly higher EtFOSE air concentrations in rooms with plastic floors compared to wood or laminate.
