Interfacial interaction between diverse microplastics and tetracycline by adsorption in an aqueous solution

Area of Science:

• Environmental Science
• Marine Biology
• Chemistry

Background:

• Microplastic pollution is a growing concern in marine ecosystems, particularly in aquaculture.
• Combined pollution of microplastics and other contaminants like antibiotics poses risks to marine life.

Purpose of the Study:

• To investigate the adsorption behavior of tetracycline (TC) on various microplastics.
• To understand the combined pollution effects of microplastics and antibiotics in aquatic solutions.

Main Methods:

• Studied adsorption of tetracycline on polyethylene (PE), polystyrene (PS), and polyvinyl chloride (PVC) microplastics.
• Analyzed the effect of microplastic type, size, and presence of metal ions (Pb2+, Cr3+, Cd2+, Zn2+, Cu2+) on TC adsorption.
• Utilized isotherm fitting to determine adsorption capacities and coefficients.

Main Results:

• Polyethylene (PE) exhibited the highest adsorption capacity and coefficient for tetracycline compared to PS and PVC.
• TC adsorption on PE decreased significantly with increasing particle size.
• Adsorption of TC onto PE was enhanced by Pb2+, Cr3+, Cd2+, and Zn2+, but reduced by Cu2+.
• Chloride ions had no significant effect on TC adsorption, indicating an ion exchange mechanism.

Conclusions:

• Microplastic surface properties and solution chemistry significantly influence tetracycline adsorption.
• The findings provide insights into the interfacial behavior and fate of microplastics and antibiotics in marine environments.
• This research offers a theoretical basis for managing combined microplastic and antibiotic pollution in aquaculture.