In a world-first, a new study has linked microplastics to an increased risk of heart attack, stroke and death.
There's growing evidence of the contaminants' presence in human bodies and scientists are worried about the harmful effects on our health.
Plastic pollution reaches almost every corner of our planet - we wrap food in it and drink from it.
Now, scientists are now linking it to heart disease.
The study from the New England Journal of Medicine analysed 257 patients with carotid artery disease, finding tiny plastic fragments in more than half of fatty clumps in the arteries.
They found it appears to increase the risk of heart attack, stroke and death compared to patients with no plastics in their system.
"I would certainly call this a concerning finding," Auckland University Associate Professor Lokesh Padhye said.
In a separate study from the University of Mexico, microplastics were found in every human placenta it tested - raising worrying questions about the health impacts on developing foetuses.
"Both of these studies have found we have an abundance of microplastics in our bodies," Prof Padhye said.
It's a problem we can't escape even at the bottom of the world, where researcher Joel Rindelaub found more microplastics in Auckland's atmosphere than London's.
"Basically everywhere we've looked for microplastics we've found them - whether that's in the ocean or even the air we're breathing. They can even fall out of the sky here in Auckland," he said.
However, what it means for human health is still a bit of a grey area.
"We need to investigate this further to find out the exact health effects of exposure to microplastics," Rindelaub said.
He is urging caution around plastic use, such as not heating food up in plastic containers because it can leach into food.
"Try to avoid using plastic as much as possible, whenever there is heating involved especially."
But avoiding it altogether isn't easy because there's probably plastic in what you're wearing, sitting on and looking at.
