US EPA

6315683 

Journal Article 

Sorption behaviour of per- and polyfluoroalkyl substances (PFASs) as affected by the properties of coastal estuarine sediments 

Oliver, DP; Navarro, DA; Baldock, J; Simpson, SL; Kookana, RS 

2020 

1 

Science of the Total Environment
ISSN: 0048-9697
EISSN: 1879-1026 

720 

137263 

English 

32145609 

10.1016/j.scitotenv.2020.137263 

WOS:000525736600129 

The sorption of three perfluoroalkyl substances (PFASs), namely perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonic acid (PFHxS), was determined in 19 coastal sediments. There are currently limited data on the sorption behaviour of these chemicals in marine or estuarine sediments and the properties controlling their sorption have not been well established. The median average PFOS Kd value (30.4 L/kg) was >8 times that for PFOA (3.3 L/kg) and PFHxS (2.8 L/kg). Highly significant (P < .001) linear relationships were found between values for sorption coefficients (Kd) for all three chemicals (PFOS, PFOA and PFHxS) to the estuarine sediments and organic carbon (OC) content with r2 values ranging from 0.87 to 0.91. The nature of the constituents of OC was determined by nuclear magnetic resonance (NMR) for a subset (10) of the sediments to assess whether the strong relationship between sorption and OC was due solely to an increasing amount of OC or to particular OC fractions. The NMR analysis could not provide strong evidence for one OC fraction type explaining the variation in sorption of the three PFASs. Further investigation using partial least squares of the whole spectra also did not show any particular OC components could explain the Kd variation. This data suggests that variation in sorption in these sediments was primarily due to the varying OC content and not its chemistry. 

PFOS; PFOA; PFHxS; Sorption; Organic carbon