permeable

https://doi.org/10.1351/goldbook.15970
Of a membrane, allowing a given substance to pass through.
Note: When applied to nonbiological membranes with no qualification, the term normally refers to water.
Source:
PAC, 2007, 79, 1153. (Glossary of terms used in toxicology, 2nd edition (IUPAC Recommendations 2007)) on page 1280 [Terms] [Paper]