Abstract
Microplastic fibres (MPFs) are increasingly being reported as one of the dominant forms of microplastic pollution in aquatic environments. Clothing and textiles produced from synthetic fibres such as polyester (PES), polyacrylic (PAC) and nylon (PA) are considered some of the main sources of MPFs. However, there has been little focus on the environmental fate and effects of MPFs compared to microplastic particles and fragments. Our previous findings show altered cell- and chlorophyll a production in marine microalgae exposed to microbeads, albeit at relatively high concentrations. In the current study, we investigate the potential for MPFs with different physical and chemical characteristics to elicit toxicological responses in freshwater and marine microalgae. Effects on algal production and photosynthetic activity were assessed as a function of polymer type, fibre length and concentration. In addition, the environmental fate of MPFs was studied by long-term mechanical and UV degradation studies using the same materials (PES, PAC and PA) under freshwater and marine conditions. A detailed chemical characterisation of the pristine test materials was conducted, using GC-MS, LC-MS and pyrolysis GC-MS to identify the type of additive chemicals present. Leaching studies were also conducted under the same freshwater and marine conditions to study the release of additive chemicals. The release of additive chemicals and their possible photodegradation to intermediate products was investigated as part of the UV degradation studies.
