First detection of the formation of polyethylene microplastics by time-of-flight secondary ion mass spectrometry (ToF-SIMS)
The current lack of analytical methods for microplastics, that is, plastic particles of a size of less than 5 mm, is hampering the assessment of consumer exposure as well as the elucidation of potential health risks mediated by these kinds of contaminants. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used at BfR to follow the generation of microplastics at the example of polyethylene (PE), the plastic material used most frequently.
Initial investigations showed that larger PE particles (approximately 5 mm) decomposed during a period of 14 days into significantly smaller particles with dimensions of sometimes below 10 micrometers. Furthermore it was demonstrated that this degradation process intensifies in the course of a month. Thus, the proportion of the smallest particle fraction with a size between 1 and 1.5 microns increased by 50 %, whereas that of the second smallest particle fraction (1.5 to 2.5 microns) increased even by 350 %. The microplastic particles generated could be clearly differentiated from the surrounding sea sand particles by mass spectrometric analysis. For this, an imaging method based on ToF-SIMS was applied.
The article has been published in the international scientific journal „Science of the Total Environment“ (Science of the Total Environment, 2016, vol. 563-564, pp.: 261-266.).
Time-of-flight secondary ion mass spectrometry (ToF-SIMS)- based analysis and imaging of polyethylene microplastics formation during sea surf simulation.
Harald Jungnickel, Ralph Pund, Jutta Tentschert, Philipp Reichardt, Peter Laux, Harvey Harbach, Andreas Luch.
Science of the Total Environment. 2016. Link: http://www.sciencedirect.com/science/article/pii/S0048969716307057