CA - Microplastics found in a quarter of San Diego estuary fish
In a sampling of fish from a creek that flows into San Diego Bay, nearly a quarter contain microplastics, according to a new study published in the journal PLOS ONE. The study, which examined plastics in coastal sediments and three species of fish, showed that the frequency and types of plastic ingested varied with fish species and, in some cases, size or age of fish.
The study reveals that species' natural history, in particular what they eat, how they feed, and how those change over their lifetimes, may influence their contamination levels. This new information on how plastics travel through the environment and into fish could help add a key piece to the emerging picture of the dynamics and impacts of plastics in California's coastal environment.
"Over the last two decades, we have started to realize the huge extent to which small plastics are entering our marine ecosystems from urban watersheds," says study lead author Theresa Talley, a California Sea Grant Extension Specialist and researcher at Scripps Institution of Oceanography at Scripps Institution of Oceanography at the University of California San Diego. "But there are still many questions to answer."
Much of this plastic enters ocean from land-based sources, and rivers—especially urban rivers—are major conduits for the flow of trash from land to sea. However, there are still a lot of questions about what happens to plastics as they break down and move through the environment, how they affect the wildlife that may consume them, what other contaminants they carry and transmit, how they move through the food web, and what impacts that environmental plastics may have on people who may be exposed to them through seafood consumption.