Why Do Non-Polar Compounds Show Less Recovery with NaCl Addition?

[Maud87]

If you want to extract more polar compunds out of water, you add NaCl
to make the water more polar. But why do the really non polar compounds
give a less recovery with the salt addition? (For example Prosulfocarb and Tri-allaat) (Pesticides)

The extraction occurs in a glass tube, so the only thing I can think of is that they react with the salt and become more polar or that they interact more with the glass

Does anybody have an idea about this?

 

[chemisttree]

If you want to extract more polar compunds out of water, you add NaCl to make the water more polar.

No. You add salt to make the compounds less soluble in the water which makes them easier to extract out of water. The term is "salting out".

But why do the really non polar compounds give a less recovery with the salt addition? (For example Prosulfocarb and Tri-allaat) (Pesticides)

The extraction occurs in a glass tube, so the only thing I can think of is that they react with the salt and become more polar or that they interact more with the glass

Does anybody have an idea about this?

No idea what you are talking about here. If true it isn't a general property of polar/non-polar compounds but something specific about thiocarbamates.