New methodologies for the detection, identification, and quantification of microplastics and their environmental degradation by-products

Abstract

Sampling, separation, detection, and characterization of microplastics (MPs) dispersed in natural water bodies and ecosystems is a challenging and critical issue for a better understanding of the hazards for the environment posed by such nearly ubiquitous and still largely unknown form of pollution. There is still the need for exhaustive, reliable, accurate, reasonably fast, and cost-efficient analytical protocols allowing the quantification not only of MPs but also of nanoplastics (NPs) and of the harmful molecular pollutants that may result from degrading plastics. Here a set of newly developed analytical protocols, integrated with specialized techniques such as pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS), for the accurate and selective determination of the polymers most commonly found as MPs polluting marine and freshwater sediments are presented. In addition, the results of an investigation on the low molecular weight volatile organic compounds (VOCs) released upon photo-oxidative degradation of microplastics highlight the important role of photoinduced fragmentation at a molecular level both as a potential source of hazardous chemicals and as accelerators of the overall degradation of floating or stranded plastic debris.

A Systematic Study on the Degradation Products Generated from Artificially Aged Microplastics

“…After artificial aging, new peaks next to the triplets are observed in the pyrolytic profiles of both HDPE and LDPE; these can be associated to oxidation products and in particular to linear ketones, linear saturated alcohols, and monocarboxylic acids. Peaks corresponding to saturated aldehydes, with lengths up to C24, increase in their relative intensity with aging ( Figure 8 ) [ 32 ]. The complete list of all the pyrolysis products detected in the chromatogram obtained in the Py–GC–MS analysis of LDPE-4w is reported in Table S5 in the Supplementary Materials .…”

Chemical Analysis of Microplastics and Nanoplastics: Challenges, Advanced Methods, and Perspectives

“…Because weathered NMPs are expected to have a higher toxicity potential, ,− the methods for the characterization of the chemical alteration of plastic particles are of importance. The process of weathering contributes to the degradation of NMPs and is driven by biotic (e.g., microbial colonization) and abiotic (e.g., photo-oxidation) factors, resulting in a modified surface topography and changes to the surface chemistry. , For the chemical analysis of particle surface modified due to weathering, FTIR technique was shown to be very efficient.…”

Untargeted selected ion flow tube mass spectrometry headspace analysis: High‐throughput differentiation of virgin and recycled polyethylene pellets

“…In recent years, SIFT-MS has been applied to quantitative analysis of residual monomers in virgin polymer pellets, 18,19 and characterization of microplastic debris in the environment. 20,21 For automated analyses, 18,19 targeted SIFT-MS approaches have been utilized most commonly, but increasingly it has been appliedin combination with multivariate statistical post-processingas an untargeted screening tool. Applications of this approach include rapid classification of Moroccan Argan oils, 22 Mediterranean olive oils, 23 strawberry flavor mixes, 24 and breath.…”