Adsorption of Copper by Naturally and Artificially Aged Microplastics and Subsequent Release in Simulated Gastrointestinal Fluid

16 August 2023, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

Microplastics, especially aged microplastics can become vectors of heavy metals from environment to organisms with potential negative effects on food chain. However, a few studies focused on the bioavailability of adsorbed metals and most studies related to aged microplastics used artificial method that cannot entirely reflect actual aging processes. In this study, virgin polystyrene was aged by ozone (PS-O3), solar simulator (PS-SS) and lake (PS-Lake) to investigate adsorption of Cu by virgin, artificially and naturally aged microplastics and subsequent release in simulated gastrointestinal fluids (SGF). Characterization results show carbonyl was formed in PS-O3 and PS-SS, and the oxidation degree was PS-O3> PS-SS> PS-Lake. However, Cu adsorption capacity followed this order PS-Lake (158 μg/g)> PS-SS (117 μg/g)> PS-O3 (65 μg/g)> PS-Virgin (0). PS-O3 showed highest Cu adsorption capacity at 0.5 h (71 μg/g), but it dropped dramatically later (10 μg/g, 120 h), because PS-O3 could break up and the adsorbed Cu released in solutions subsequently. For PS-Lake, precipitation of metallic oxides contributes to the accumulation of Cu. The addition of dissolved organic matter (DOM) could occupy adsorption sites on PS and compete with Cu, but also can attach PS and adsorb Cu due to its rich functional groups. The simultaneous ingestion of microplastics with food suggested that adsorbed Cu is solubilized mostly from aged PS to SGF.

Keywords

microplastics
aging
ozone
lake
copper
gastric fluid
polystyrene

Supplementary materials

Title
Description
Actions
Title
Adsorption of Copper by Naturally and Artificially Aged Microplastics and Subsequent Release in Simulated Gastrointestinal Fluid
Description
Supporting information
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.