Thanks for the recommendation. This is helpful. We'll look into ISTA testing as well as potential impacts on barrier performance and shelf life with PCR
Original Message:
Sent: 05-01-2026 12:37 PM
From: Rino Jacob
Subject: Seeking Industry Perspective: Compatibility Testing for Vendor and Resin Changes
Hi Fenghua,
In my experience with polymer laminates, transitioning from virgin to PCR resin is high-risk for bridging results. PCR introduces molecular variability that can compromise package integrity. I suggest a risk-based study focusing on:
ISTA Pre-qualification: Vibration/drop tests (e.g., ISTA 3A) are vital, as PCR often has different stress-cracking resistance.
Shelf-Life & Barrier Shifts: PCR can alter the polymer matrix, changing OTR and WVTR profiles. This is critical for protecting active ingredients.
Regards,
Rino Jacob
Packaging Engineer
HAZMAT & Advanced Materials Specialist
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Rino Jacob
Sparks NV
(585) 766-8346
Original Message:
Sent: 04-27-2026 09:57 AM
From: Fenghua Zeng
Subject: Seeking Industry Perspective: Compatibility Testing for Vendor and Resin Changes
Hi IoPP community,
I'd love to get your thoughts and best practices on compatibility testing and test-result bridging in cosmetic packaging.
For primary packaging in the cosmetic industry, if the package remains essentially the same in format and dimensions, and the material family is the same (for example PE tube to PE tube), but the packaging is sourced from a different vendor using a different resin grade/source, would you typically:
- require a full compatibility / stability test
- perform a risk-based reduced study
- or bridge the previous test results with a scientific justification?
I'm particularly interested in how you assess cases where the only changes are:
- same material type, different resin/vendor
- virgin resin to PCR
- PCR back to virgin
For those who allow bridging, what key elements do you include in your bridging statement / technical justification?
For example, do you typically evaluate:
- resin type and grade equivalency
- barrier properties (O₂ / moisture / light)
- extractables / leachables risk
- additive package differences
- product formula sensitivity (fragrance, acids, actives, alcohol, etc.)
- component-process differences (extrusion / injection / multilayer)
Would appreciate any examples of change control rationale, risk assessment frameworks, or wording for bridging statements that have worked well in cosmetics.
Thank you in advance for sharing your experience.
Best Regard,
Feng
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Fenghua Zeng
Elmhurst NY
(917) 328-0573
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