Plastic pollution as an emerging threat to deep-sea bioluminescence

Abstract

Bioluminescence is a predominant phenomenon in marine environments, the production of light by living organisms through enzyme-mediated chemical reactions involving luciferin, the light-emitting substrate and luciferase, the enzyme that catalyses its oxidation. In the deep sea, bioluminescence is not merely a visual trait but a critical ecological function supporting prey capture, mate recognition, communication and other species interactions. Recent evidence indicates that plastic exposure can alter bioluminescent responses through ingestion, tissue stress, oxidative damage and interference with chemical signalling pathways. This is of growing concern because plastic debris and microplastics are increasingly detected from surface waters to abyssal environments, making them bioavailable to deep-sea organisms. Since many deep-sea organisms depend on bioluminescence for survival and reproduction, any impairment of light production mechanisms can influence not only individual fitness but also prey–predator interactions, trophic transfer and ecosystem functioning. This letter highlights plastic pollution as an emerging threat to deep-sea bioluminescence and calls for long-term monitoring and policy attention to protect biological light-mediated ecological processes in the deep ocean.