Does zinc oxide lose its UV blocking properties when mixed with oil?

Zinc oxide provides strong protection against UVA and UVB radiation. Does $\ce{ZnO}$ retain this protection when it is dissolved in oil?


When $\ce{NaCl}$ is dissolved in water, the $\ce{Na+}$ and $\ce{Cl-}$ ions are pulled apart by the water molecules. I would assume that a similar thing happens when $\ce{ZnO}$ is dissolved in oil, where the $\ce{Zn^2+}$ is separated from the $\ce{O^2-}$ ions.


Also, according to [Wikipedia — Zinc oxide](https://en.wikipedia.org/wiki/Zinc_oxide),



> 
> ZnO reacts slowly with fatty acids in oils to produce the corresponding carboxylates, such as oleate or stearate.
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> 
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But that still doesn't tell me whether that would lead to a loss of the UV protective properties.




$\ce{ZnO}$ is not soluble in oils. But it can form dispersion in oils. $\ce{ZnO}$ may react with traces of fatty acids in oils, forming respective zinc salts. But for UV screening context, it is negligible negative effect. $\ce{ZnO}$ does not lose in such a case its properties, there is just little less of it there.


The major factor in UV screening context is difference in refraction indexes of $\ce{ZnO}$ ( or $\ce{TiO2}$ ) particles and the fluid (liquid or gas). The bigger difference means stronger light scattering and longer average UV path through the given layer.


With a longer optical path comes also better UV absorption by the used liquid, more exactly by UV absorption additives.


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