This essay was written by Lower Sixth Form student Joel Sellers as an Original Research in Science (ORIS) project. It was the winning submission in the ORIS category of the 2024 ILA/ ORIS award. The following provides a short abstract of the full report, which can be found below:
Plastics, and particularly microplastics (MPs, plastic pieces <5mm), are ubiquitous and have developed into a serious issue for our marine environments. Not only do they pose a threat to aquatic organisms directly exposed to plastic pollution, but there is also a potential risk to humans further down the line, due to prolonged exposure to these small particles through the food they eat, the air they breathe, or the water they drink. Scientific evidences have been provided showing that plastic polymers have been detected in human blood, as well as in the placenta or human stool. Consequently, it is critical to assess the sources of MPs exposure to humans. One source is table salt, particularly when it comes from sea salt. The characterisation and detection of such small particles remain an analytical challenge due to their small size, the quantity of material available, the colour of the material, and the natural organic matter that can adsorb onto MPs degraded in the environment. Raman spectroscopy is one of the leading tools for MPs analysis as it is non-destructive and requires little to no sample preparation with a spatial resolution of 1 mm. However, in order to identify these tiny pieces of plastic, reference spectra are needed. There are many obstacles in providing these spectra that make building up a library challenging. This project set out to not only initiate the process of creating a plastic polymer library using Raman spectroscopy, but also to identify potential interferences. 15 different samples of plastic litter were analysed and added to the library, and possible challenges were identified. The project provided a foundation for further research and development.
The Unchained Library 