The recycling of polyethylene (PE) film is a straightforward process, provided the material that is being recycled has come from a clean source and is consistent in composition. Most waste film recovered for recycling has been subjected to a series of ‘life cycle factors’, e.g. comingling with wastes such as dirt, packaging tapes, and other plastic film products. Such contamination can degrade the material's physical properties and this article presents quantitative data on the effects of contaminants on PE films. Results suggest that dirt contamination can adversely affect the elasticity and melt viscosity of the polymer, but the contaminant does not interact directly with it and that polypropylene-based packaging tape is more suited to mechanical recycling than polyvinyl chloride or cellulose-based tapes.