It's those beads again. That is, small plastic particles, or microplastics, found in many toothpastes and cosmetics are endangering Pacific oysters (Crassostrea gigas) and their reproduction, according to a new study from France's national marine research agency.

While scientists have known for some time that microplastics greatly impact marine life, what's surprising about the recent study is how those tiny grains can impact future generations. 

Oysters rely on a filter-feeding system, so they are prone to ingesting tiny plastic particles along with many other things in the water. In the latest study, researchers tested Pacific oysters in tanks and found that oysters exposed to microplastics produced smaller eggs and less mobile sperm compared to a control group of oysters in a tank that did not contain microplastics.

In fact, after two months of consuming plastics, oysters produced 41 percent fewer offspring, which grew more slowly than normal.

Millions of tons of plastics wind up in the world's oceans every year, and it is estimated that by around 2050 there will be more plastic than fish, by weight.

But researchers are increasingly concerned about microplastics -- the bits that are smaller than five millimeters -- because common products like face wash and toothpaste go straight down the drain instead of being discarded properly, according to, an anti-microplastics campaign. (Scroll to read more...)

While birds and sea turtles have been seen chocking on plastic debris in the ocean, researchers are not entirely sure how these tiny plastics are impacting oysters. It may be that they are interfering with oysters' hormones, blocking their digestive systems and making it harder for them to eat food and get energy. 

Furthermore, researchers say the oysters may be mistaking microplastic particles for phytoplankton, as they are about the same size. 

The study findings, recently published in the Proceedings of the National Academy of Sciences, highlight the devastating impact microplastics can have on marine environments and reinforce the need to act on the problem. 

"Anthropogenic litter is something we can do something about quite quickly if we want to," Tamara Galloway, an ecotoxicologist at the University of Exeter, said in a statement. 

So, while the U.S. government is making strides to reduce plastic consumption -- including recently passed legislation banning microbeads -- one simple way consumers can help is by using less plastic and being more careful about waste disposal.

Related Articles 

Ocean Pollution: 8 Trillion Microbeads a Day from US

Marine Waste: Cleanser Can Release 100,000 Micro-Beads

Sea Turtles Threatened By Plastic Pollution, Researchers Say

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