Evaluation of microplastics release from solar water disinfection poly(ethylene terephthalate) and polypropylene containers

Public health concern associated with the ingestion of microplastics (MPs) released from water packaging materials is increasing. The use of plastic materials for solar disinfection (SODIS) containers has also raised concerns in the SODIS community due to the lack of studies evaluating the presence of MPs in the treated water. In this work, the migration of MPs from poly(ethylene terephthalate, PET) bottles and polypropylene (PP) translucent and transparent jerrycan containers (TJC) into water under natural weathering was investigated using micro-reflectance Fourier Transform Infrared Spectroscopy (µ-FTIR). Containers exposed to sunlight for three months became photodegraded, releasing micro-sized fragments identified as PET, PP and high-density polyethylene (HDPE, from the screw-caps), although with varying degrees of weathering. It is noteworthy that the presence of a clarifying additive in PP formulation did not seem to impact the release of MPs from the containers. The study showed that PP TJC containers released more MPs than PET bottles. Finally, the size of MPs was measured to determine their fate upon ingestion and highlights the need for further studies to understand the safety of these plastic containers for SODIS. [Display omitted] •MPs were detected in the water from the three SODIS devices studied.•Weathering effects on particle surface can cause misidentification of PP MPs.•Addition of a clarifier in PP formulation did not have an effect on MP release.•PP TJCs experienced higher MP release than PET bottles due to low photostability.•MP particle size has been correlated to potential health hazards in human beings.