# Non-saturation correction factor

The presence of air in soils has a huge effect on potential soil transport of nanoparticles. The exact reasons for this are unclear, but some hypothesize that presence of air bubbles causes extra straining and/or that air/water interaction occurs at air or water interfaces with the soil. Taking into account this interaction is thus necessary, but difficult as the exact magnitude of this effect is highly variable with soil structure and the amount of air present in the soil. We have, however, found indications that apparent attachment in soil columns increases monotonously in soils. As a first approach, we therefore assume a linear increase of the attachment efficiency  with the degree of saturation. The slope of this increase is the non-saturation (unsaturated) correction factor.

$$\LARGE f$$ non-saturated

## Used for

Air/water interaction

## Procedure

 Nionshio Unsaturated column test Soil transport calculation                                 Non-saturation correction

 NanoFASE Report D7.2 Soil property - NM fate relationships  NanoFASE Report D7.4 Module for NM exposure prediction in soils to couple to overall framework OECD technical guideline 312

## Contact

Geert Cornelis

Swedish University of Agricultural Sciences (SLU)

Email: geert.cornelis@slu.se