Journal
ENVIRONMENTAL POLLUTION
Volume 291, Issue -, Pages -Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.envpol.2021.118120
Keywords
Agriculture film; Carbofuran; Carbendazim; Dissolved organic matter; Density functional theory
Categories
Funding
- National Natural Science Foundation of China [41877117, 41977126, 42077131, 42007122]
- Key Field Research & Development Program of Guangdong Province [2019B020218002]
- Innovation Team Project of Agriculture and Rural Affairs Office of Guangdong Province [2019KJ132]
Ask authors/readers for more resources
Polyethylene (PE) and polypropylene (PP) microplastics (MPs) act as carriers for pesticides like carbofuran and carbendazim (CBD), showing high adsorption rates and capacities. The presence of dissolved organic matter (DOM) affects the adsorption behavior, with larger MPs having lower capacities. The primary adsorption mechanisms are through intermolecular van der Waals forces, with electrostatic interactions explaining the higher adsorption of CBD compared to carbofuran by MPs.
Polyethylene (PE) and polypropylene (PP) microplastics (MPs), as carriers, can bind with pesticides, which propose harmful impacts to aqueous ecosystems. Meanwhile, carbofuran and carbendazim (CBD), two widely used carbamate pesticides, are toxic to humans because of the inhibition of acetylcholinesterase activity. The interaction between two MPs and two pesticides could start in farmland and be maintained during transportation to the ocean. Herein, the adsorption behavior and mechanism of carbofuran and carbendazim (CBD) by PE and PP MPs were investigated via characterization and density functional theory (DFT) simulation. The adsorption kinetic and thermodynamic data were best described by pseudo-second-order kinetics and the Freundlich models. The adsorption behaviors of individual carbofuran/CBD on both MPs were very similar. The CBD adsorption rate and capacity of PE and PP MPs were higher than those of carbofuran. This phenomenon explained the lower negative effects of DOM (oxalic acid, glycine (Gly)) on CBD adsorption relative to those of carbofuran. The presence of oxalic acid and Gly decreased the PE adsorption by 20.40-48.02% and the PP adsorption by 19.27-42.11%, respectively. It indicated the significance of DOM in carbofuran cycling. The adsorption capacities were negatively correlated with MPs size, indicating the importance of specific surficial area. Fourier transformation infrared spectroscopy before and after adsorption suggested that the adsorption process did not produce any new covalent bond. Instead, intermolecular van der Waals forces were one of the primary adsorption mechanisms of carbofuran and CBD by MPs, as evidenced by DFT calculations. Based on the zeta potential, the electrostatic interaction explained the higher adsorption CBD by MPs than carbofuran.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available