Untargeted Screening Chemistry for Post Consumer Polyolefin Recycling
Untargeted screening by GC-MS and LC-HRMS combined with Threshold of Toxicological Concern metrics establishes legal food-contact safety for recycled polyolefins.
Untargeted Screening
Meaning
Analytical techniques identify all chemical compounds present in a material without a predefined list of substances to search for. High-resolution mass spectrometry is the primary tool for untargeted screening in polymer science. This approach captures the full chemical profile of a resin, including unintentional impurities and degradation products.
It is different from targeted methods that only look for specific known additives.
Substance Detection
Discovery of unexpected molecules requires sophisticated software to compare measured peaks against large chemical databases. During untargeted screening, the laboratory identifies additives that may have been introduced through regrind or contaminated processing equipment. This provides a complete picture of the material purity.
Migrant Identification
Chemicals that could leach out of a plastic part are scrutinized to ensure they do not pose a health risk. Use of untargeted screening is standard for food contact materials where non-intentionally added substances must be monitored. The process reveals the presence of catalysts or side-reaction products from the polymerization stage.
Advanced chromatography separates the individual components of the extract for identification against vast libraries. This thoroughness ensures that every potential contaminant is accounted for before the product reaches the consumer.
Safety Assessment
Exhaustive data allow for a more thorough evaluation of the risks associated with a new resin formulation. Results from untargeted screening help a company decide if a material is suitable for sensitive applications like medical devices. This testing prevents the market release of parts containing harmful or restricted chemicals.