Health and environmental assessment of a single well-controlled polyethylene plastic

When dealing with industrial plastics (polymers plus additives), most approaches are using marketed materials where the polymer is identified, but not the additives. Additives used in plastics are incorporated at various stages of the synthesis and compounding by different companies which are not disclosing their recipes. In the present work, a low-density polyethylene (PE)was compounded with six common additives in two concentrations in a similar way as to industrially prepared films: antioxidants, UV protectors, and anti-slip agents. This gives a PE plastic where all ingredients are known. The additives were fully characterized by 1H NMR, 13C NMR, FT-IR, DSC, GC-MS, and LC-MS. The presence of non-intentionally added substances (NIAS), coming from impurities, degradation materials or molecules synthetized during processing, was studied with the same techniques.Being fully characterized, this PE plastic was first transferred to other laboratories to evaluate their impacts and toxicity in different environmental land compartments: soil, soil biosphere, rhizosphere and plastisphere. Processed into films, the same PE plastic was weathered in a UV-water tank with waves. The migration of additives and creation of microplastic particles into the water were measured and the chemical, physical and mechanical changes of the films were monitored, enabling to mimic the fate of PE plastic films in oceans. Finally, this PE plastics was placed in contact with human skin to search if some additives can migrate through the skin. Using Franz diffusion cells with damaged and non-damaged human skin, migrating additives were extracted from the skin and receptor fluid.The preparation of a well-controlled PE plastic and its use in different environmental and health conditions allows to realize how complex can be the assessment of the danger(s) of a single plastic material.