The prized Pacific oyster population is facing a diminutive but powerful enemy: tiny pieces of plastic floating in the ocean are affecting oysters' ability to reproduce, a new study reveals. The so-called "microplastics" include microbeads, which until recently were included in a number of personal care products from toothpaste to body scrub and face wash for their exfoliating effects.
Science Recorder notes that "While dangerous for all ocean life, microbeads are particularly problematic for filter feeding organisms, [such as oysters], which mistake them for the phytoplankton they consume as prey."
In the study, which was published in the Proceedings of the National Academy of Sciences, researchers filled two tanks of water with live oysters: One was filled with normal water, the other with microplastic-contaminated water. "Exposed oysters produced 41 percent fewer larvae and, even when those larvae matured, they grew at a slower rate and were 18 percent smaller than larvae from the unexposed tanks," Science Recorder explains.
Thanks to a bipartisan bill signed into law by President Obama at the tail end of 2015, it's now illegal for manufacturers of personal care products to use microbeads. But that doesn't do anything to clean up the literal tons of tiny plastic beads that are currently floating around in the world's oceans: According to a study published in Environmental Science & Technology prior to the ban, "8 trillion microbeads per day [were] emitted into aquatic habitats in the United States"; that's enough to cover the surface of 300 tennis courts.
Of course, oysters certainly aren't the only sea creatures facing adverse effects from rampant ocean pollution: Much ado has been made about potentially harmful levels of mercury found in salmon. But there are plenty of naturally occurring substances that are creating problems for the seafood industry, too, like the high levels of domoic acid that put a major damper on California's Dungeness crab season and vibrio bacteria that killed more than a dozen oyster-eaters in Florida last year.