Study Finds Ocean Cleanup Efforts Can Benefit Marine Life and Climate

By Dr. Noopur JainReviewed by Laura ThomsonJun 9 2025

In a recent article published in the journal Scientific Reports, researchers presented an impact assessment framework designed to evaluate the trade-offs involved in cleaning the North Pacific Garbage Patch (NPGP), focusing on how such efforts influence marine life and the broader carbon cycle in the ocean. By applying the framework to The Ocean Cleanup's latest technology—System 03—the authors aim to determine if the benefits of removing macroplastics outweigh potential environmental harms, including carbon emissions generated during cleanup operations.

Background

Oceanic plastic pollution has become a global concern, with the NPGP representing one of the most concentrated sources of floating debris. This accumulation is driven by complex ocean currents that trap plastics in a large-scale gyre, creating a persistent mass of debris that threatens marine ecosystems and human livelihoods.

Past efforts have focused on legislative measures, reduction of single-use plastics, and microplastic regulation; however, these policies have yet to stem the problem at its core.

Initiatives such as the deployment of specialized cleanup technologies seek to physically remove plastics from these high-density areas. Nonetheless, concerns linger about the potential unintended consequences of such interventions, including impacts on marine fauna and microplastic fragmentation, as well as greenhouse gas emissions resulting from vessel operations involved in cleanup efforts.

Existing research suggests that microplastics can significantly affect ocean processes like carbon sequestration, raising questions about the net environmental impacts of remediation. Therefore, building an evaluation framework that accounts for ecological benefits and possible harms is essential to inform sustainable strategies.

The Current Study

The study’s methodology centers on a framework for assessing net environmental benefits, which involves quantifying impacts across various ecological and chemical parameters. This approach considers the extent, duration, intensity, reversibility, and frequency of potential impacts from plastic pollution and cleanup activities.

The authors performed a scoring system to evaluate the vulnerability of different marine species, the ecosystem functions affected by macro- and microplastics, and impacts from cleanup operations. These impact scores, ranging from 1 (low) to 3 (high), were derived through literature review, data analysis, and expert judgment, and then subjected to iterative review to minimize bias.

The assessment incorporated a physical model of The Ocean Cleanup’s System 03, which involves towing a floating barrier with a mesh screen to collect surface plastics. The analysis estimated the volume of plastics to be recovered under various scenarios, ranging from treating macroplastics to removing 80% of debris, over different timescales.

The authors also evaluated the cleanup process's carbon footprint by calculating fuel consumption and resulting greenhouse gas emissions, assuming that burning one ton of fuel releases 3.2 tons of CO₂. These emissions were compared against proxies for the potential long-term impacts of microplastic pollution on carbon cycling and sequestration, based on available empirical data and modeling studies.

Results and Discussion

The findings reveal that marine organisms generally exhibit higher vulnerability to plastic pollution than to the impacts of cleanup activities, which tend to be localized, shorter in duration, and more controllable. Specifically, impact scores indicated that macroplastic and microplastic pollution impose considerable risks through entanglement, ingestion, and habitat disruption, with microplastics especially impacting plankton and small fish.

These microplastics have the potential to significantly reduce primary productivity, organic matter remineralization, and zooplankton grazing—key processes for oceanic carbon export—potentially decreasing the ocean’s capacity to sequester carbon by tens of millions of tons annually.

Conversely, cleanup operations, primarily involving vessel emissions, produce a relatively small carbon footprint—estimated at around 0.4 to 2.9 million metric tons of CO₂ emissions over the projected operation periods—compared to the potential long-term costs of microplastic-induced degradation of ocean carbon cycling.

Notably, the analysis suggests that removing macroplastics could substantially reduce risks like entanglement for large marine species and help bring debris concentrations below ecological thresholds.

An 80% removal target is projected to significantly decrease macroplastic levels, lowering the associated harm to marine fauna such as mammals and turtles. However, the authors acknowledge persistent microplastic pollution from external sources, contributing to ocean contamination regardless of macroplastic cleanup efforts.

The study also discusses the limitations inherent in impact scoring, including uncertainties surrounding microplastic effects and the challenge of precisely modeling long-term environmental feedback.

Conclusion

The study concludes that targeted cleanup efforts, particularly in high-density plastic hotspots like the NPGP, are environmentally beneficial when considering ecological impacts and carbon cycle dynamics. The authors emphasize that removing macroplastic pollution provides tangible benefits for marine life by mitigating entanglement and ingestion risks and potentially restoring some aspects of the ocean’s carbon sequestration capacity.

While vessel emissions associated with cleanup are non-negligible, they remain comparatively minimal against the backdrop of long-term ecosystem impacts from persistent plastic debris. The developed impact assessment framework offers an adaptable, scientific approach to evaluating ocean remediation projects' complex trade-offs. It is recommended for broader application across different marine environments and future initiatives.