A low-cost system to simulate environmental microplastic weathering

Society concerns about the potential thread of microplastics into the environment call for detailed laboratory and field studies to assess their fate, in particular, their weathering. This can hardly be done in natural conditions and, so, a low-cost system (< EUR 1000) to accelerate photooxidative and hydrolytic weathering is presented in a way that standardizes major marine experimental conditions: incident radiation range, light intensity, temperature and mechanical stress. The system can be valid for many European countries, most US states, and other intermediate-latitude-countries; otherwise it can be scaled up easily. Validation was done by studying three different polymeric structures: polyamide 6.6, polystyrene and polypropylene. The results agreed nicely with previous reports derived from different working conditions. Therefore, this low-cost system would likely contribute to the standardization of microplastic marine weathering studies by, e.g., improving their inter-comparability.