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Influence of surface oxidation on the quantification of polypropylene microplastics by pyrolysis gas chromatography mass spectrometry
The Science of The Total Environment2021
64 citations
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Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Score: 45
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0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Stephen D. Burrows,
Stephen D. Burrows,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Tania Toapanta,
Stacey O’Brien,
Stacey O’Brien,
Stacey O’Brien,
Stacey O’Brien,
Stacey O’Brien,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Kevin V. Thomas
Elvis D. Okoffo,
Elvis D. Okoffo,
Kevin V. Thomas
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Stacey O’Brien,
Stacey O’Brien,
Stacey O’Brien,
Francisca Ribeiro,
Francisca Ribeiro,
John M. Colwell,
John M. Colwell,
Kevin V. Thomas
Sarah Ede,
Elvis D. Okoffo,
Elvis D. Okoffo,
Francisca Ribeiro,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Tania Toapanta,
Stacey O’Brien,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Elvis D. Okoffo,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Michael Gallen,
Kevin V. Thomas
Kevin V. Thomas
Elvis D. Okoffo,
Stacey O’Brien,
Elvis D. Okoffo,
Stacey O’Brien,
Stacey O’Brien,
Elvis D. Okoffo,
John M. Colwell,
Francisca Ribeiro,
Francisca Ribeiro,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Stephen D. Burrows,
John M. Colwell,
Sarit Kaserzon,
Francisca Ribeiro,
Michael Gallen,
Elvis D. Okoffo,
Elvis D. Okoffo,
Elvis D. Okoffo,
Kevin V. Thomas
Stacey O’Brien,
Elvis D. Okoffo,
Sarit Kaserzon,
Kevin V. Thomas
Sarah Ede,
Tania Toapanta,
Elvis D. Okoffo,
Tania Toapanta,
Elvis D. Okoffo,
Elvis D. Okoffo,
Francisca Ribeiro,
Stephen D. Burrows,
Elvis D. Okoffo,
Kevin V. Thomas
Kevin V. Thomas
Stephen D. Burrows,
Kevin V. Thomas
Kevin V. Thomas
Tania Toapanta,
Francisca Ribeiro,
Francisca Ribeiro,
Sarit Kaserzon,
Kevin V. Thomas
Stephen D. Burrows,
Kevin V. Thomas
Michael Gallen,
Stephen D. Burrows,
Sarit Kaserzon,
Elvis D. Okoffo,
Kevin V. Thomas
Kevin V. Thomas
Michael Gallen,
Stacey O’Brien,
Elvis D. Okoffo,
Tania Toapanta,
Kevin V. Thomas
Kevin V. Thomas
Tania Toapanta,
Elvis D. Okoffo,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Sarit Kaserzon,
John M. Colwell,
Sarit Kaserzon,
Michael Gallen,
Tania Toapanta,
Kevin V. Thomas
Kevin V. Thomas
John M. Colwell,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Sarit Kaserzon,
Andrew K. Whittaker,
Tania Toapanta,
Tania Toapanta,
Kevin V. Thomas
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Francisca Ribeiro,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Sarit Kaserzon,
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Kevin V. Thomas
Elvis D. Okoffo,
Elvis D. Okoffo,
Kevin V. Thomas
Elvis D. Okoffo,
Kevin V. Thomas
Summary
Photo-oxidation of polypropylene microplastics affected their quantification by pyrolysis-GC/MS, with surface oxidation reducing measured PP mass by up to 30% relative to virgin material due to changes in thermal degradation products, indicating that environmental weathering introduces systematic bias into thermoanalytical quantification of aged microplastics.
The influence of photo-oxidation on the quantification of isotactic polypropylene by Pyrolysis Gas Chromatography/Mass Spectrometry (Pyr-GC/MS) was assessed. Beads (oval shape, ~5 mm) and fragments (irregular shaped, 250-50 μm and 500-1000 μm) were subjected to relatively harsh simulated accelerated weathering conditions (using a filtered xenon-arc reproducing sunlight's full spectrum) for up to 37 and 80 days, respectively. Samples collected (n = 10 replicates for each treatment) at increasing number of weathering days were analysed by Fourier-transform infrared spectroscopy with Attenuated Total Reflection (FTIR-ATR), scanning electron microscopy, and differential scanning calorimetry in order to assess the extent and the rate of degradation. The rate of surface oxidation occurred faster for fragments compared to beads, probably due to their higher surface area. Quantification of the polypropylene trimer (2,4-dimethyl-1-heptene) via double shot Pyr-GC/MS, showed that the signal of the trimer relative to the mass of polypropylene was reduced through weathering with a degradation rate of 1:3 faster for fragments over beads. Signal reduction and carbonyl index were correlated to show that polypropylene with a carbonyl index of ≥13 has a significantly reduced 2,4-dimethyl-1-heptene signal when compared to virgin material. Consequently, the quantification of polypropylene subjected to weathering under harsh conditions may be underestimated by 42% (fragments, carbonyl index: 18) to 49% (beads, carbonyl index: 30) when quantified by Pyr-GC/MS and using virgin polypropylene calibration standards. Pyrolysis at a lower temperature (350 °C) identified six degradation specific markers (oxidation products) that increased in concentration with weathering. Further comparisons between virgin and weathered microplastics may need to be considered to avoid underestimation of microplastic concentrations in future studies.