The polarity of a solution can be quantified by several means, including the Schnieder solvent classification, dielectric constant, or partion coefficients. However, I've found that quantifying the polarity of a solid is difficult. The internactions occuring for solids and liquids are different, but I beleive polarity still plays a role in these interactions. For example, hydrophobic compounds will have a much higher affinity for activated carbon as opposed to a salt.