Vehicles are unique indoor environments, with interiors dominated by plastic/synthetic materials and exposure to extremes of temperature and radiation, leading to substantial potential for emissions of plastic additives from vehicle materials and subsequent exposure to drivers and passengers. Flame retardants (FRs) and per- and polyfluoroalkyl substances (PFAS) were measured in 30 dust samples collected from dashboards, seats, and trunks of cars of the same make and model (year of manufacture 1996-2021) to evaluate levels in dust and time patterns in additive use across cars of different ages. PFAS were detected in all dust samples at low levels, while FRs were detected in all samples, with some compounds consistently exceeding µg/g levels, especially tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and decabromodiphenyl ether (BDE-209), substantially higher than in other indoor environments. Although cars were of the same model, large variations were observed in FR concentrations in dust between cars, emphasizing the challenge in generalizing FR exposures from vehicle dust. Concentrations of BDE-209 in vehicle dust did not decrease over the 1996-2021 period, suggesting that restrictions on DecaBDE have had limited impact, likely due to exemptions in regulations for the automotive industry. The high FR levels indicate ongoing use of both organophosphate and brominated FRs in vehicles on the European market, although flammability standards for interior car materials are not mandated by European regulations, and the continued presence of long-restricted FRs suggests the presence of recycled plastics in vehicles; this potential exposure source may be increasing as vehicle producers aim to improve material circularity.

• Keywords
• Cars, Dust exposure, Flame retardants, PFAS, Time trends,
• MeSH
• Automobiles MeSH
• Halogenated Diphenyl Ethers analysis   MeSH
• Environmental Monitoring * MeSH
• Organophosphates * analysis   MeSH
• Dust * analysis   MeSH
• Flame Retardants * analysis   MeSH
• Air Pollution, Indoor * analysis   statistics & numerical data   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• decabromobiphenyl ether MeSH Browser
• Halogenated Diphenyl Ethers MeSH
• Organophosphates * MeSH
• Dust * MeSH
• Flame Retardants * MeSH

This study investigates the efficacy of supramolecular solvent (SUPRAS) in extracting a diverse spectrum of organic contaminants from indoor dust. Initially, seven distinct SUPRAS were assessed across nine categories of contaminants to identify the most effective one. A SUPRAS comprising Milli-Q water, tetrahydrofuran, and hexanol in a 70:20:10 ratio, respectively, demonstrated the best extraction performance and was employed for testing a wider array of organic contaminants. Furthermore, we applied the selected SUPRAS for the extraction of organic compounds from the NIST Standard Reference Material (SRM) 2585. In parallel, we performed the extraction of NIST SRM 2585 with conventional extraction methods using hexane:acetone (1:1) for non-polar contaminants and methanol (100%) extraction for polar contaminants. Analysis from two independent laboratories (in Norway and the Czech Republic) demonstrated the viability of SUPRAS for the simultaneous extraction of twelve groups of organic contaminants with a broad range of physico-chemical properties including plastic additives, pesticides, and combustion by-products. However, caution is advised when employing SUPRAS for highly polar contaminants like current-use pesticides or volatile substances like naphthalene.

• Keywords
• Indoor environments, PFAS, Pesticides, Plastic additives, SUPRAS,
• Publication type
• Journal Article MeSH