Molecular insights: The dynamic dance of nanoplastics and natural organic matter

A new study offers new insights into how nanoplastics interact with natural organic matter, crucial for understanding their role in pollution and the carbon cycle. The research reveals that nanoplastics initially form aggregates through hydrophobic forces, followed by binding via van der Waals interactions. These findings are vital for developing strategies to manage nanoplastic spread in aquatic environments.

Nanoplastics, emerging as persistent environmental pollutants, pose significant threats due to their durability and wide distribution in water bodies. Their interactions with natural organic matter are critical, influencing pollutant retention, microbial processes, and the carbon cycle. However, the structural complexity of both aged nanoplastics and natural organic materials complicates their study. This complexity necessitates advanced research to clarify how these interactions contribute to ecological risks.

Researchers from Northwest A&F University and South China Agricultural University have published a study (DOI: 10.1016/j.eehl.2024.08.004) in Eco-Environment & Health on September 11, 2024, that explores the interaction between nanoplastics and natural organic matter through molecular modeling. The study uses molecular dynamics simulations and density functional theory (DFT) to investigate the aggregation mechanisms of polyethylene, polyvinyl chloride, and polystyrene nanoplastics in both their pristine and aged states.

The study reveals that pristine nanoplastics aggregate through hydrophobic interactions, forming compact clusters that attract natural organic matter. Aged nanoplastics, having undergone chemical changes such as oxidation, engage in more complex interactions, including cation bridging with Ca²⁺ ions, hydrogen bonding, and electrostatic forces. These findings suggest that the aging process increases the reactivity of nanoplastics, affecting their behavior in aquatic systems and potentially altering ecosystem stability.

Dr. Hanzhong Jia, the lead researcher, emphasized the importance of these findings, stating, “Our study sheds light on the molecular-level processes that drive nanoplastic aggregation in aquatic environments. Understanding these mechanisms is crucial for predicting their behavior and assessing the long-term environmental impacts of nanoplastics.”

The research provides valuable insights for environmental scientists and policymakers. A deeper understanding of nanoplastic interactions with organic matter could guide efforts to combat plastic pollution, refine ecological risk assessments, and develop new water purification technologies aimed at removing these contaminants.

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References

DOI

10.1016/j.eehl.2024.08.004

Original Source URL

https://doi.org/10.1016/j.eehl.2024.08.004

Funding information

This work was supported by the National Natural Science Foundation of China (Grants No. 42107263). We thank the High-Performance Computing Center (HPC) of Northwest A&F University (NWAFU) for providing computing resources and National Center for Supercomputing in Xi'an.

About Eco-Environment & Health (EEH)

Eco-Environment & Health (EEH) is an international and multidisciplinary peer-reviewed journal designed for publications on the frontiers of the ecology, environment and health as well as their related disciplines. EEH focuses on the concept of "One Health" to promote green and sustainable development, dealing with the interactions among ecology, environment and health, and the underlying mechanisms and interventions. Our mission is to be one of the most important flagship journals in the field of environmental health.