Microplastics Found in Dolphin Breath: A New Threat to Marine Mammals

Microplastics have long been a concern for ocean health, but a recent study reported in the Guardian has revealed a startling new finding: dolphins are inhaling these harmful particles when they come up for air. This marks the first time microplastics have been detected in dolphin breath, raising concerns about the potential impact on their respiratory systems. 

The groundbreaking research, conducted by a team from the United States, sheds light on how airborne microplastics are making their way into marine environments and affecting wildlife. Published in the journal PLOS One, the study focused on bottlenose dolphins in two distinct locations: Sarasota Bay, Florida, a busy urban estuary, and the more rural Barataria Bay, Louisiana. Despite the differences in these environments, microplastics were found in the exhaled breath of all 11 dolphins sampled.   

Airborne Microplastics: A New Exposure Route 

While much of the concern around microplastics has focused on ingestion through food and water, this research highlights inhalation as another significant exposure route for marine animals. Microplastics, which can be carried by wind over long distances, are now being detected in even the most remote environments, such as Mount Everest. The fact that dolphins, animals known for their deep, powerful breaths, are inhaling these particles is particularly worrying. It suggests that larger lung capacities may expose dolphins to higher concentrations of microplastics than humans or other animals. 

Leslie Hart, a public health expert from the College of Charleston in South Carolina and co-author of the study, expressed concern about the potential health risks for dolphins. “Dolphins have a much larger lung capacity and are taking deep breaths, which could mean they are exposed to higher doses of microplastics than we are,” Hart explained. 

What Are Microplastics and Where Do They Come From? 

Microplastics are tiny fragments of plastic, smaller than 5 mm, that originate from a variety of sources, including the breakdown of larger plastic items and the shedding of synthetic fibers from clothing. Many of the particles found in the dolphins’ breath were polyester, a material commonly used in clothing. When clothes made from polyester are washed, especially in hot water, they shed significant amounts of microplastics into the environment. Over time, these particles make their way into the air, water, and eventually into the lungs of wildlife like dolphins. 

The researchers used an innovative method to collect exhaled air from the dolphins. By holding petri dishes over the dolphins’ blowholes as they came up for air, the team was able to capture samples of their breath. In both the urban and rural locations, microplastics were present in every sample, confirming that these particles are not limited to more industrialized areas. 

Health Implications for Dolphins 

This discovery is particularly concerning for dolphins in areas like Barataria Bay, Louisiana, where many animals are still suffering the effects of the 2010 Deepwater Horizon oil spill. Dolphins in this region have already experienced significant respiratory issues, and the inhalation of microplastics could worsen these health problems. Although the full impact of inhaling microplastics on dolphins’ lungs is still unknown, studies on humans have shown that microplastic inhalation can lead to lung inflammation and respiratory issues.  

A Call for Action 

While this study provides valuable insights into the exposure of dolphins to airborne microplastics, it also underscores the broader issue of plastic pollution. Microplastics are now found everywhere, from remote mountain peaks to the depths of the ocean, and their presence in the air suggests that no ecosystem is safe from contamination. 

As the research continues, scientists are urging policymakers and environmental organisations to take more aggressive action against plastic pollution. That’s where Take 3 for the Sea comes in: with our global movement of people connected to the ocean, our collective action can make a difference. Everyone can join the movement and unleash the power of three: 

• Take 3 pieces of rubbish with you when you leave the beach, waterway… or anywhere 
• Take 3 actions to reduce your single-use plastic
• Take 3 people on the journey with you 

By reducing our reliance on plastic, removing plastic waste from the environment and spreading the message to others, we can help protect both marine life and our own health from the dangers of microplastic pollution.