Analytical Pyrolysis for monitoring and characterization of microplastics in environmental matrices Sabiqah Tuan Anuar, Ammarluddin Ali, Nurul Izzati Abul Razak, Yusof Shuaib Ibrahim, Wan Mohd Afiq Wan Mohd Khalik, Ku Mohd Kalkausar Ku Yusof, Maisarah Jaafar, Lee Bai Qin, Chin Teen Teen
Microplastic Research Interest Group (MRIG), Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
Abstract
The increasing human population has made the demands for resources and gathering areas which resulted in expansion of terrestrial urban areas, thus now intruding the coastal territory. The introduction of municipal waste, and unregulated management of trash not only brought ecological changes, but also, negatively affect many organisms living therein especially through pollution and food scarcity. Microplastics, at sizes less than 5 mm, can affect the further up the food web through bioaccumulation, bioavailability, and biomagnification. Traditional qualitative method for microplastics analysis alone is inadequate without precise polymer identification. This study emphasized the use of the thermal degradation method of pyrolysis-GC/MS as characterization technique to identify the type and concentration of microplastic in analytical volume of sample matrices. Pyrolysis-GC/MS measurement were carried out at 600 oC (pyrolyzer temperature) and an optimized selective ion monitoring (SIM) mode for MS was used to analyze selected polymer standards. Individual standard calibration was performed before the method was applied to real sample matrices. The samples of environmental matrices (water and biota) were collected around the east coast of peninsular Malaysia (South China Sea) and were subjected to digestion and extraction processes using a wet peroxidation method before microplastics were physically observed and analyzed. A detail thermal degradation profile using an optimized pyrolysis-GC/MS method indicates that pyrolytic products for polypropylene, polyethylene, PET, Nylon, PMMA and chlorinated polyethylene were successfully detected. The technique gives additional information about the chemical constituent and suggested that the sample can be coming from complex polymer component or different polymer materials in one single sample. This study provides an insight of the level of microplastic pollution in biota samples found in Malaysia and discusses the need of appropriate characterization methods for complex sample matrix.
Keywords: microplastics, plastic pollution, Malaysia, fish, polychaete, surface water
