"Food-safe" or "RoHS compliant" on a datasheet is only meaningful when backed by a specific test method. This page explains the two most common laboratory techniques used to verify silicone parts — ICP-OES for metals and GC-MS for organic compounds — and what a real test report tells you.
Why Advanced Testing Matters
Standard hardness and tensile tests tell you how a part performs. Advanced analytical tests tell you what is in the material — the trace metals and organic compounds that regulations like RoHS, EN 71-3 and California Proposition 65 limit. For food, baby, medical and electronics applications, these tests are what separate a claim from a certificate.
- Compliance: prove the part meets RoHS, EN 71-3, Prop 65 and food-contact limits.
- Quality control: catch batch-to-batch contamination before parts ship.
- Safety: confirm no regulated substance exceeds its detection limit.
ICP-OES — Detecting Heavy Metals
Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) ionizes a dissolved sample in a high-temperature plasma and measures the light emitted at characteristic wavelengths. It detects metals such as lead (Pb), cadmium (Cd) and mercury (Hg) down to parts-per-million (mg/kg) levels.
It is the standard technique for verifying RoHS (lead, cadmium, mercury, hexavalent chromium) and EN 71-3 toy-safety limits on silicone.
GC-MS — Detecting Organic Compounds
Gas Chromatography–Mass Spectrometry (GC-MS) separates organic compounds in a sample and identifies each by its mass spectrum. It is used to detect phthalates and other organic contaminants, supporting compliance with California Proposition 65 and food-contact migration limits.
What a Real Report Shows
| Test | Method | Typical regulated substances |
|---|---|---|
| Heavy metals (ICP-OES) | IEC 62321 series | Lead, cadmium, mercury, hexavalent chromium |
| Phthalates (GC-MS) | CPSC-CH-C1001-09.4 | DEHP, DBP, BBP, DINP |
| Toy safety | EN 71-3 | Migratable heavy metals |
A useful report states the method, the result per substance, and the method detection limit (MDL) — not just a "PASS" stamp.
How CYES SILICONE Supports This
We verify hardness, dimensions and mechanical properties in-house, and provide third-party analytical reports for regulated substances on request. Our testing equipment page lists the instruments behind our dimensional, mechanical and environmental checks, and our advanced characterization page covers the full extended test set — from TML/CVCM outgassing to extractables and leachables.
See testing & measuring equipment for our in-house capability, and advanced characterization for the full parameter set we document on request.