A Converter Certificate That Does Nothing for an Uncertified Mill
A converter's chain of custody certificate cannot retroactively grant certified status to packaging made from uncertified paper mill substrate.
EN 12498
Extraction Protocol
Analytical quantification of heavy metal impurities in paper and board intended for food contact relies on aqueous extraction under mild conditions. The protocol established in EN 12498 determines cadmium, chromium, lead and other extractable elements in aqueous test solutions obtained from pulp, paper or packaging specimens. Testing evaluates water-soluble trace elements capable of migrating into aqueous and fatty food simulants.
This method stops applying when total elemental composition is required, which necessitates complete acid digestion of the solid matrix rather than cold aqueous extraction.
Digestion Chemistry
Laboratory preparation involves wetting paper samples with demineralized water and maintaining controlled agitation at room temperature. The testing process outlined in EN 12498 produces a filtered aqueous leachate that is acidified for stabilization. Inductively coupled plasma mass spectrometry or atomic absorption spectroscopy measures elemental concentrations in the liquid phase.
Contamination in sizing starches, recycling pulps or mineral fillers transfers extractable heavy metals into the finished board.
Food Compliance
Chemical safety regulations enforce strict limits on heavy metal migration to prevent human toxicological exposure from food packaging. Paperboard packaging must pass extraction testing under EN 12498 before receiving regulatory clearance for dry, fatty and aqueous food contact applications. Recycled boards often carry residual printing pigments and processing aids that increase soluble trace metal counts.
Verifying extraction levels guarantees that heavy metal migration remains well below European regulatory limits. Mills monitor water quality and pulp supplies to eliminate heavy metal contamination at the wet end. Compliant test results provide formal verification for downstream packaging converters and food brand owners.
Packaging materials that clear this extraction test show minimal risk of elemental leaching into sensitive food items.