Formation of Environmentally Persistent Free Radicals on Microplastics under Light Irradiation

Microplastics (MPs) are presumed to be inert during aging under ambient conditions. In this study, four types of virgin MPs, including polystyrene (PS), phenol-formaldehyde resin (PF), polyethylene (PE), and polyvinyl chloride (PVC), were aged under simulated solar light irradiation. Surprisingly, several environmentally persistent free radicals (EPFRs), which are considered to be a type of emerging contaminant, were detected on the irradiated PS and PF, rather than PE and PVC, by electron paramagnetic resonance (EPR) spectroscopy. Depending on the photoaging duration time, the characteristic g-factors of the EPFRs produced on PS and PF were 2.0044-2.0049 and 2.0043-2.0044, respectively. The generated EPFRs on…

• NN
  National Natural Science Foundation of China

  Awards: 21737003, 41571446
• YI
  Youth Innovation Promotion Association of the Chinese Academy of Sciences

  Award: 2016380
• SK
  State Key Laboratory of Pollution Control and Resource Reuse

  Award: PCRRF17020