Unraveling Complexation and Contaminant Vector Potential in Aged Polyamide-Heavy Metal Interactions
Chanat Chokejaroenrat1, Nan Hammawiboon1, Parada Weaoseng1
1Department of Environmental Technology and Management, Faculty of Environment, Kasetsart University, Bangkok 10900, Thailand.
ACS Omega
|December 1, 2025
Summary
Aged polyamide (PA) microplastics act as vectors for heavy metals like cadmium and copper. Environmental factors influence metal release, highlighting PA
Area of Science:
- Environmental Science
- Materials Science
- Chemistry
Background:
- Polyamide (PA) microplastics are widespread environmental contaminants from aquatic activities.
- Aged PA microplastics can adsorb and transport heavy metals, posing ecological risks.
- Understanding metal adsorption and release from aged PA is crucial for environmental risk assessment.
Purpose of the Study:
- To investigate the impact of aged polyamide microplastics on the environment.
- To determine the role of aged PA as a vector for heavy metals (cadmium and copper).
- To analyze the adsorption and desorption behavior of metals on aged PA under various conditions.
Main Methods:
- PA microplastics were artificially aged using heat-activated persulfate.
- Adsorption of cadmium and copper onto aged PA was studied over time.
- Metal concentrations were measured using ICP-OES; adsorption kinetics and isotherms were determined.
Main Results:
- Aged PA showed enhanced adsorption capacity for cadmium and copper, attributed to increased surface area and roughness.
- Copper exhibited higher adsorption efficiency due to its ionic properties and coordination with PA functional groups.
- Adsorption followed pseudo-second-order kinetics and Langmuir isotherms, indicating electrostatic interactions.
Conclusions:
- Aged PA microplastics act as dual contaminants, persisting in the environment and transporting heavy metals.
- Environmental factors significantly affect metal adsorption and desorption on aged PA.
- This study underscores the need to consider aged microplastics as vectors for hazardous metal pollution in aquatic ecosystems.
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