Nothing visible happens. Which is what makes it the dangerous one.
What sorption is
A molecule from the product dissolving into the container wall or the liner, rather than reacting with it. The wall acts as a solvent.
It is driven by chemistry, not by damage
A polyolefin wall is a hydrophobic medium, and a lipophilic active or preservative partitions into it. Nothing about the container looks different afterwards.
So the usual checks miss it
The container is intact, the closure seals, the product is clear and the volume is right. The assay is the only thing that notices.
And it is time dependent
Partitioning continues until equilibrium, so a release assay at day zero can be fine and a six month assay can be out of specification.
Which puts it squarely inside the clause
Absorptive so as to alter the strength of the drug beyond the established requirements. Strength is one of the five attributes named.
The surface area matters as much as the material
A small fill in a large container has a high surface to volume ratio and loses more. On this shelf capacity runs 15 to 237 mL with a median of 118, so filling the right size is part of the answer.
Which is why it is recorded on 350 of the 486 rows here. A foamed polyethylene liner is a polyolefin surface pressed against the product every time the container is inverted.
Glass is the default answer for a reason
46 of the 106 containers on this shelf are glass, and glass does not sorb. Its weakness is impact, rated 1 of 5 against polypropylene's 4.
So the trade is sorption against breakage
Glass is inert and fragile; polypropylene is tough and absorbs. That is the real choice on this shelf and both options are stocked.
Our data narrows it and does not decide it
Two materials, two ratings, and a pairing question that needs a study. We publish the first two and cannot supply the third.
References
21 CFR 211.94, "Drug product containers and closures". (a) "Drug product containers and closures shall not be reactive, additive, or absorptive so as to alter the safety, identity, strength, quality, or purity of the drug beyond the official or established requirements." (b) "Container closure systems shall provide adequate protection against foreseeable external factors in storage and use that can cause deterioration or contamination of the drug product." (c) "Drug product containers and closures shall be clean and, where indicated by the nature of the drug, sterilized and processed to remove pyrogenic properties to assure that they are suitable for their intended use. Such depyrogenation processes shall be validated." (d) "Standards or specifications, methods of testing, and, where indicated, methods of cleaning, sterilizing, and processing to remove pyrogenic properties shall be written and followed for drug product containers and closures." Part 211 is current good manufacturing practice for finished pharmaceuticals; compounding under section 503A of the Federal Food, Drug, and Cosmetic Act carries conditional exemptions from certain requirements including cGMP, and nothing here asserts that this section applies to any particular compounder.
law.cornell.eduThe Davis Pack Supply catalog, measured 19 October 2026. Our published material properties are a five-point rating on five attributes, per material class rather than per product: Chemical Resistance, Clarity, Impact Resistance, Rigidity and Scratch Resistance. For the two materials on this shelf, glass is rated Chemical Resistance 5 of 5, Clarity 5, Rigidity 5, Scratch Resistance 5 and Impact Resistance 1; polypropylene is rated Chemical Resistance 4, Clarity 5, Rigidity 5, Scratch Resistance 5 and Impact Resistance 4. Ten material classes are rated in total. These are a screening tool on a resin family and not a compatibility finding for a formulation.
The Davis Pack Supply catalog, measured 19 October 2026. 486 rows: 106 containers and 380 closures, which are the same rows the cannabis topicals group returns. 15 to 237 mL with a median of 118. 60 PP and 46 glass. 84 jars, 17 bottles, 4 tubs and pails, 1 tube. 28 white, 26 clear, 17 natural, 13 black, 12 amber, 6 blue, 4 frosted. Necks: 18 at 70-400, 16 at 89-400, 14 each at 58-400 and 53-400, 8 at 18DIN, 7 at 43-400, 5 unrecorded. Liners on the closures: 119 heat induction seal, 51 F217, 47 pressure sensitive, 33 No Liner, 32 Plastis standard, 30 unrecorded, 27 foam, 25 PE foam, 10 Plastis pasteur, 3 polycone.
