Leaching characteristics, toxicity and adsorption capacities of micro-plastic beads

Plastic pollution is a ubiquitous and growing global problem. Past studies have shown that not only are plastics a source of chemical contaminants to environment, but also a sink of organic pollutions in the environment. Typically, polymers and plasticizers can be released from plastics into the aquatic environment, which might then be directly ingested by humans via usage of plastic products. Moreover, harmful organic contaminants present in the environment can be adsorbed onto plastics or polymers, which then get transported along with the plastics ingested by aquatic organisms, and eventually affecting humans as well. These phenomena are undesirable and hence this project aimed to investigate both the leaching characteristics and adsorption capacities of plastics. In this work, six common plastics (PS, PE, PP, PC, PET and PVC) were chosen. After an 28-hour exposure to deionised water, leachates were analysed for their size, morphology and elemental components. In the analysis of molecular weights, two peaks were found, which suggest leachates are mainly 20K or very small (MW<1000). Elements detected through EDX analysis suggest the presence of common additives CaCO3, SiO2, CaSiO3 and NaCl in the plastics. Hence, GC-MS and LC-QTOF were employed to identify the small (MW