# Extractables and Leachables (E&L) in Cosmetic Pipettes: Testing Rubbers and Elastomers
TL;DR — More buying conversations around cosmetic pipettes now include an extractables and leachables (E&L) question, and the question usually lands first on the rubber and elastomer parts: the bulb, the tube, the sealing part. On the program side the dropper family is verified at 73 catalog models on glass and PET bottle bodies with capacity rows of 3/5/8/10, 10/15, 30, and 100/120 ml — and the boundary is just as clear: extractables and leachables testing is not a published program capability; an E&L study is a project-level exercise conducted with the customer or a qualified laboratory. This article walks through how such a study is organized, from material disclosure to the analytical verdict, and hooks the conversation back to the verified compatibility capability.
Why: The Pipette E&L Question Is Getting Deeper
A pipette looks simple and answers slowly. Every drop it dispenses passes through — or past — a bulb, tube, collar, and sealing part, and any of those can be rubber or elastomer. That is why the question is deepening at every stage of the buying process:
- At inquiry — buyers increasingly ask about extractables and leachables for pipettes before a formula is even paired to a package, and the first target is always the rubber-like parts;
- At specification — the parts that touch the formula, or sit in its headspace, become the scope of study, and elastomer bulbs and seals are where the scope concentrates;
- At documentation — the buyer wants the answer as a report with a method and a conclusion, in the project file, not as a general statement from a datasheet.
The record side does the honest work here: it states which pipettes exist, what the family is built on, and which testing capabilities are verified — and it does not pretend an E&L program exists when only a project can hold one.
How: Organizing an E&L Exercise for a Pipette Project
3.1 Material disclosure: define the part first
An E&L exercise starts with disclosure, not with an instrument. Every extractable or leachable finding must be traceable to a part and a material, so the first step is a complete list of the pipette's contacting and near-contact parts — bulb, tube, collar, gasket, and any elastomer insert — together with what each is made of.
That disclosure is where the program boundary shows itself clearly. No elastomer material is recorded in the material register; pipette elastomer parts are project-specified. And the parts themselves follow the same path: pipette sub-components are part of the project design, not recorded catalog components. What the register does anchor is the product side — the dropper family of 73 catalog models, glass and PET bottle bodies, and capacity rows of 3/5/8/10, 10/15, 30, and 100/120 ml — so the project's disclosure sits on a verified family record rather than on a default material assumption.
3.2 Extraction design: aging, solvents, and conditions
The industry method family for E&L is a two-stage inquiry: extractables first, under deliberately aggressive conditions, then leachables under conditions closer to real use. Accelerated aging, extraction solvent selection, and the exposure regimes involved are established methodology in the industry — described here as general industry guidance, because no figure survives contact with a specific project.
That is the rule the record enforces: extractables and leachables testing is not a published program capability; an E&L study is a project-level exercise conducted with the customer or a qualified laboratory. Which solvents, which temperatures and durations, and worst-case versus typical exposure are all decisions the study itself makes — configured per project, in the project's documentation.
3.3 Analysis and the verdict
The analytical stage follows standard practice: separation and detection techniques in the GC and LC families identify what the extraction released and quantify it, and the results are then evaluated against the thresholds that apply to the product's destination. Thresholds are not universal — they follow the product type and the destination market — so the verdict is always a per-project conclusion, recorded in the project file.
3.4 The compatibility hook and the project report
When the study closes, its conclusion lands on the program's verified quality hooks. The compatibility test is a verified capability of the quality program and the closest gate to an E&L question; the dosage/output test covers the dispense side. Both are capability-level — the parameters and results stay with the project.
The deliverable is documentation per project: the material list, the extraction design, the analytical data, and the conclusion, packaged as the project's E&L record. The claim direction is worth stating plainly: wording like "extractables-free" or "leach-free" is not a catalog credential — it is a conclusion that only this study record can support, phrased as such, per project.
<pre class="language-mermaid"><code>flowchart LR
A[Pipette project<br/>dropper family 73 catalog models] –> B[Material disclosure<br/>elastomer parts per project]
B –> C[E&L study design<br/>project-level, not a published capability]
C –> D[Extraction + analysis<br/>aging, solvents, GC/LC methodology]
D –> E{Verdict per project}
E –> F[Compatibility hook<br/>verified capability]
F –> G[Documentation per project]
G –> H[Release per project]
</code></pre>
What: Verified Program Data and the Verification Hooks
- Product family: the dropper family records 73 catalog models;
- Bottle bodies: glass and PET;
- Capacity rows: 3, 5, 8, 10, 10/15, 30, and 100/120 ml;
- Materials register: no elastomer material is recorded in the material register; pipette elastomer parts are project-specified;
- Component register: pipette sub-components are part of the project design, not recorded catalog components;
- E&L status: extractables and leachables testing is not a published program capability; an E&L study is a project-level exercise conducted with the customer or a qualified laboratory;
- Verification hooks (capability-level): the compatibility test (verified) and the dosage/output test; no parameters or results are published.
Gotchas
- There is no default bulb material. No elastomer material is recorded in the material register, so a project that assumes a "standard" bulb from the catalog will not find one — which is exactly why the disclosure step comes first.
- E&L is not a package you can order. It is not a published program capability; the study is a project-level exercise with the customer or a qualified laboratory, and its design belongs to the project file.
- Method figures do not exist before the study. Accelerated-aging conditions, extraction solvents, and thresholds are configured per project; any number quoted at RFP stage is a discussion point, not program data.
- The compatibility hook is the closest gate, not the study itself. A verified compatibility capability supports the pairing conversation; an E&L conclusion needs the study's own documentation behind it.
- "Free" claims need the record. Extractables-free or leach-free phrasing is a claim direction that only the study record can support — it is never a catalog statement.
- Capacities are verified; migration behavior is not. The 3–120 ml capacity rows are recorded; how a specific elastomer behaves under a specific formula remains a per-project test.
Related Resources
- Category: Droppers
- Related insight: Dropper & Pipette Viscosity Calibration · Micro Dropper Tip Orifice & Drop Volume · PCR Decontamination & Traceability · The 12-Test Lab Matrix
- Quality & Testing Capabilities — compatibility and dosage/output testing, configured per project