Behavior of perfluorinated compounds in soils during leaching experiments

Short-chained PFASs have low sorption affinity in soils and potentially high mobility.

“indicating their low sorption affinity in soils and their potentially high mobility (Gellrich et al., 2012).”

Subsurface leaching of PFAS during intermittent infiltration of water was shown to increase with flow rate.

“For instance, subsurface leaching of PFAS during intermittent infiltration of water was shown to increase with flow rate (Gellrich et al., 2012;Hoisaeter et al., 2019).”

Other soil properties such as hydraulic conductivity, soil chemical heterogeneity, air-water interface, and protein, iron oxide, and manganese oxide content may also contribute to variable PFAA transport in subsurface soil.

“It should be noted that other soil properties such as hydraulic conductivity, soil chemical heterogeneity, air-water interface, and protein, iron oxide, and manganese oxide content may also contribute to variable PFAA transport in subsurface soil (Gellrich et al., 2012;Guelfo et al., 2020;Hoisaeter et al., 2019;Longstaffe et al., 2012;Lyu et al., 2018;Ololade et al., 2016).”

PFAAs may migrate down the subsurface due to leaching and redistribution, and sorbed PFAS can desorb and leach leading to downward migration.

“First, PFAAs may migrate down the subsurface due to leaching and redistribution of PFAAs in the subsurface.Sorbed PFAS compounds can desorb and leach from the soil, which can lead to their downward migration through the subsurface (Gellrich et al., 2012).”

The air-water interface can also leach sorbed PFAAs from the soil when the subsurface is exposed to intermittent rainfall, increasing its mobility through the subsurface to the groundwater.

“On the other hand, the air-water interface can also leach sorbed PFAAs from the soil when the subsurface is exposed to intermittent rainfall, increasing its mobility through the subsurface to the groundwater (Gellrich et al., 2012).”