A metrologically traceable protocol for the quantification of trace metals in different types of microplastic.
The presence of microplastic (MP) particles in aquatic environments raised concern about possible enrichment of organic and inorganic pollutants due to their specific surface and chemical properties. In particular the role of metals within this context is still poorly understood. Therefore, the aim...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2020-01-01
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| Series: | PLoS ONE |
| Online Access: | https://doi.org/10.1371/journal.pone.0236120 |
| _version_ | 1819017065947725824 |
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| author | Lars Hildebrandt Marcus von der Au Tristan Zimmermann Anna Reese Jannis Ludwig Daniel Pröfrock |
| author_facet | Lars Hildebrandt Marcus von der Au Tristan Zimmermann Anna Reese Jannis Ludwig Daniel Pröfrock |
| author_sort | Lars Hildebrandt |
| collection | DOAJ |
| description | The presence of microplastic (MP) particles in aquatic environments raised concern about possible enrichment of organic and inorganic pollutants due to their specific surface and chemical properties. In particular the role of metals within this context is still poorly understood. Therefore, the aim of this work was to develop a fully validated acid digestion protocol for metal analysis in different polymers, which is a prerequisite to study such interactions. The proposed digestion protocol was validated using six different certified reference materials in the microplastic size range consisting of polyethylene, polypropylene, acrylonitrile butadiene styrene and polyvinyl chloride. As ICP-MS/MS enabled time-efficient, sensitive and robust analysis of 56 metals in one measurement, the method was suitable to provide mass fractions for a multitude of other elements beside the certified ones (As, Cd, Cr, Hg, Pb, Sb, Sn and Zn). Three different microwaves, different acid mixtures as well as different temperatures in combination with different hold times were tested for optimization purposes. With the exception of Cr in acrylonitrile butadiene styrene, recovery rates obtained using the optimized protocol for all six certified reference materials fell within a range from 95.9% ± 2.7% to 112% ± 7%. Subsequent optimization further enhanced both precision and recoveries ranging from 103% ± 5% to 107 ± 4% (U; k = 2 (n = 3)) for all certified metals (incl. Cr) in acrylonitrile butadiene styrene. The results clearly show the analytical challenges that come along with metal analysis in chemically resistant plastics. Addressing specific analysis tools for different sorption scenarios and processes as well as the underlying kinetics was beyond this study's scope. However, the future application of the two recommended thoroughly validated total acid digestion protocols as a first step in the direction of harmonization of metal analysis in/on MP will enhance the significance and comparability of the generated data. It will contribute to a better understanding of the role of MP as vector for trace metals in the environment. |
| first_indexed | 2024-12-21T02:57:36Z |
| format | Article |
| id | doaj.art-ce0f765b653e46cdb2bc511063a8e7e8 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-21T02:57:36Z |
| publishDate | 2020-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-ce0f765b653e46cdb2bc511063a8e7e82022-12-21T19:18:17ZengPublic Library of Science (PLoS)PLoS ONE1932-62032020-01-01157e023612010.1371/journal.pone.0236120A metrologically traceable protocol for the quantification of trace metals in different types of microplastic.Lars HildebrandtMarcus von der AuTristan ZimmermannAnna ReeseJannis LudwigDaniel PröfrockThe presence of microplastic (MP) particles in aquatic environments raised concern about possible enrichment of organic and inorganic pollutants due to their specific surface and chemical properties. In particular the role of metals within this context is still poorly understood. Therefore, the aim of this work was to develop a fully validated acid digestion protocol for metal analysis in different polymers, which is a prerequisite to study such interactions. The proposed digestion protocol was validated using six different certified reference materials in the microplastic size range consisting of polyethylene, polypropylene, acrylonitrile butadiene styrene and polyvinyl chloride. As ICP-MS/MS enabled time-efficient, sensitive and robust analysis of 56 metals in one measurement, the method was suitable to provide mass fractions for a multitude of other elements beside the certified ones (As, Cd, Cr, Hg, Pb, Sb, Sn and Zn). Three different microwaves, different acid mixtures as well as different temperatures in combination with different hold times were tested for optimization purposes. With the exception of Cr in acrylonitrile butadiene styrene, recovery rates obtained using the optimized protocol for all six certified reference materials fell within a range from 95.9% ± 2.7% to 112% ± 7%. Subsequent optimization further enhanced both precision and recoveries ranging from 103% ± 5% to 107 ± 4% (U; k = 2 (n = 3)) for all certified metals (incl. Cr) in acrylonitrile butadiene styrene. The results clearly show the analytical challenges that come along with metal analysis in chemically resistant plastics. Addressing specific analysis tools for different sorption scenarios and processes as well as the underlying kinetics was beyond this study's scope. However, the future application of the two recommended thoroughly validated total acid digestion protocols as a first step in the direction of harmonization of metal analysis in/on MP will enhance the significance and comparability of the generated data. It will contribute to a better understanding of the role of MP as vector for trace metals in the environment.https://doi.org/10.1371/journal.pone.0236120 |
| spellingShingle | Lars Hildebrandt Marcus von der Au Tristan Zimmermann Anna Reese Jannis Ludwig Daniel Pröfrock A metrologically traceable protocol for the quantification of trace metals in different types of microplastic. PLoS ONE |
| title | A metrologically traceable protocol for the quantification of trace metals in different types of microplastic. |
| title_full | A metrologically traceable protocol for the quantification of trace metals in different types of microplastic. |
| title_fullStr | A metrologically traceable protocol for the quantification of trace metals in different types of microplastic. |
| title_full_unstemmed | A metrologically traceable protocol for the quantification of trace metals in different types of microplastic. |
| title_short | A metrologically traceable protocol for the quantification of trace metals in different types of microplastic. |
| title_sort | metrologically traceable protocol for the quantification of trace metals in different types of microplastic |
| url | https://doi.org/10.1371/journal.pone.0236120 |
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