Meaning
Molecular ring structures consisting of carbon and hydrogen atoms that frequently appear in petroleum based packaging. It measures the potential for chemical migration into food and stops applying when the molecules are fully contained by a functional barrier.
Structural Ring
Saturated and aromatic versions of these compounds define the migration risks associated with food contact materials. Cyclic hydrocarbons can originate from the base resin itself or from the solvents used in surface coatings. Their shape allows them to pass through certain polymer matrices more easily than straight chains.
Some versions contain multiple rings that increase the boiling point and reduce volatility.
Migration Pathway
Diffusion through the packaging wall occurs when the temperature of the contents increases or during long storage periods. Testing for these molecules involves soaking the plastic in food simulants like olive oil or ethanol. If the concentration in the food exceeds safety limits, the packaging must be redesigned with a functional barrier.
This migration is particularly rapid in low density polymers with high free volume.
Health Assessment
Toxicological studies evaluate the impact of these compounds on human health to set safe exposure levels. Aromatic rings are generally viewed with more concern due to their potential for accumulation in body tissues. Regulators use these findings to establish legal migration limits for the global plastics industry.
