Whales May Be Consuming Up to 10 Million Microplastic Particles Each Day

The environmental hazards of an industrialized world are well-documented, but a recent study highlights an alarming new reality: In their search for food, whales could be ingesting as many as 10 million microplastic pieces daily.

In their paper, published this week in *Nature Communications*, scientists from multiple West Coast institutions analyzed the feeding patterns of tagged blue, fin, and humpback whales off California's coast from 2010 to 2019. These baleen whales often foraged for krill and small fish between 50 and 250 meters (164 to 820 feet) beneath the ocean's surface, where the highest concentrations of microplastics, particles similar in size to sand grains, were found. Krill consumed these plastics, which were then delivered to the whales when the small crustaceans were eaten.

Simply by consuming their usual prey, blue whales may unintentionally ingest up to 10 million microplastic pieces each day. Fin whales, the second largest species on Earth, can ingest between 3 to 10 million pieces. Humpback whales, which favor anchovies and herring over krill, can still take in around 200,000 microplastic particles, while other whale species might swallow up to 1 million pieces daily.

The alarming statistics likely suggest that whales may be suffering from a lack of proper nutrients. Even though they are consuming enough food, the prey could be of lower nutritional value—similar to humans eating junk food. This spells trouble for at-risk and endangered cetaceans.

"Whale populations, including blue, fin, and humpback whales, are still on the path to recovery after being hunted, and in some regions, their numbers remain below 10 percent of what they once were," explains lead author Shirel Kahane-Rapport, now a postdoctoral scholar at California State University, Fullerton, to Mytour. "We believe microplastic pollution is an additional human-induced stressor that will further hinder their recovery, alongside other threats like ship collisions and ocean noise."

Whales aren’t the only marine creatures impacted by plastic pollution, but they do have the biggest appetites—and possibly the highest risk from ingesting microplastics. Beyond reducing the nutritional value of their food, microplastics may also harm the whales' stomach lining or even enter their bloodstream, though scientists are still investigating these potential effects. More research is needed to understand how environmental factors concentrate plastic waste at the whales' prime feeding locations and the long-term impacts of a high-plastic diet.

Kahane-Rapport suggests that individuals can make a difference by "disposing of waste properly to prevent it from ending up in the sewer, and by adding a simple filter to your washing machine to catch microfibers." She also advocates for citizens to push their local leaders for more responsible practices. "Supporting better wastewater treatment to stop microplastics from entering the water system by engaging with local council members and politicians can help drive broader change," she explains. "Additionally, pressuring large corporations to manage their waste responsibly is crucial."