More plastic, less glow? Pollution threatens deep sea’s bioluminescent life, experts warn

Plastic pollution could be disrupting the bioluminescent light produced by deep-sea organisms, according to researchers who warn of the threat in a letter published in the journal Cambridge Prisms: Plastics. When these organisms ingest plastics, it may disrupt the chemical pathways that create bioluminescence and harm their body tissues, hindering their ability to locate food and a mate, the authors explained.

Deep-sea environments are home to up to 80% of organisms with complex cells, making bioluminescence their sole source of illumination in the ocean's darkest regions. The light these creatures emit is crucial for their survival and reproduction, the letter emphasizes. Disrupting their bioluminescence could have detrimental effects on food webs and ecosystem functions in the deep sea, the largest and least-explored biome on Earth, the authors note.

Co-author Renjith VishnuRadhan of Amity University in India provided an example to illustrate the significance of this issue, mentioning the anglerfish. "Female deep-sea anglerfish are widely recognized from documentaries and films like Finding Nemo," he explained. "Their modified dorsal spine ends in a luminous lure called the esca, which is produced by symbiotic bacteria.

The light generated by these bacteria helps attract prey and may also play a role in recognition or communication in the absence of light." VishnuRadhan stated that bacterial bioluminescence has been shown to be affected by pollutants, and the ingestion of toxic plastic additives by anglerfish could potentially disrupt the bacterial symbiosis in the lure, thereby affecting its luminous signaling.

While there is some evidence of plastic pollution impacts on deep-sea ecosystems, scientists lack the high-quality data and observations necessary to fully understand the consequences of this pollution.