Coconut filters woven using Native Hawaiian techniques capture coastal microplastic and sunscreen pollution and support fungal bioremediation

Coastal ecosystems are facing a growing threat from microplastic pollution and sunscreen contaminants, which often require synthetic materials for clean-up that contribute to further carbon emissions or only remove pollutants without proper treatment. This study examines coconut husks, a readily available and biodegradable agricultural byproduct, as a dual-purpose solution for capturing pollutants and promoting microbial bioremediation.

The researchers isolated fungi from coconut husks to assess their potential for bioremediation, finding that 24 fungal isolates thrived under conditions containing plastic or sunscreen. Several of these fungi belong to genera known for their ability to degrade plastic, such as Chaetomium, Curvularia, Meyerozyma, Cladosporium, and Fusarium.

The team then created filtration modules using coconut husks, fibers, and leaves, inspired by the traditional Hawaiian method of weaving coconut leaf hats (papale lau niu). In trials, the woven devices were able to capture up to 76.58% of suspended microplastic particles within two minutes and significantly reduce the net turbidity of the surrounding water, decreasing sunscreen concentrations by an average of 533.51 NTU compared to control trials with no filter.

This research presents a natural, innovative approach to pollution cleanup that capitalizes on coconut-based materials, traditional techniques, and the resilience of microbial communities to provide a sustainable and cost-effective solution.