Plastic particles are found in our organs, blood and even semen. But do they stay in us forever? What damage are they doing? Here are six questions scientists are trying to answer.

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The new study has scientists concerned that microplastics may be contributing to reproductive health issues.

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Recycling "does not solve the solid waste problem," the head of a plastics trade group said in 1989, around the time the industry was launching its recycling campaign.

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Worried about the proliferation of plastic trash in the environment and her own body, a journalist tried to shop plastic-free for 7 days. She found plastic in a lot of sneaky and surprising places.

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Tiny plastic debris — some so small you can't see it — has previously been found in human blood, excrement and in the depths of the ocean.

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A new study suggests there is far more plastic in the Atlantic Ocean than scientists estimated earlier, especially tiny pieces of plastic that can end up inside fish and other animals.

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The World Health Organization says that the tiny particles of plastic found everywhere in the environment do not appear to pose any significant risk to human health.

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China is no longer taking the world's waste. The U.S. recycling industry is overwhelmed — it can't keep up with the plastic being churned out. This doesn't bode well for our plastic waste problem.

(Image credit: Saul Loeb)

Giant gyres of plastic in the ocean grab headlines, but it's the tiny bits of plastic that scare scientists. And they've made their way everywhere, a new study finds — including in our seafood.