Experts are warning that humans "have the most to lose" from the manmade, toxic pollutants that marine life are being exposed to.
By Thomas Moore, Health and Science Correspondent
A leading scientist has told Sky News that the millions of tonnes of plastic pollution floating in the world's oceans could pose a threat to human health.
Dr Robbie Smith, from the Bermuda Natural History Museum, warned plastic rubbish is attracting other chemical pollutants washed into the sea - such as flame retardants and pesticides - as sunlight breaks plastic down and waves churn it into tiny fragments.
Because the plastic pieces look so similar to the natural prey of marine animals, the chemicals then get passed up the food chain.
Dr Smith said: "The more we look where plastic is and the form it's in, big or small, the stronger it is integrated into food webs.
"The only place it can go once it is in the food web is up to the top, and we are sitting at the top. So we have the most to lose here."
Scientists have already found evidence of toxic chemicals in other predators at the top of the marine food chain.
Sky News joined the Ocean Tech team on an expedition to the Challenger Bank several miles off the Bermudan coast.
There, the scientists caught a three-metre (9.8ft) tiger shark and took biopsies from its fin for toxicology tests.
Choy Aming, who is part of the team, said: "As animals are digesting, the animals they have eaten have also ingested the toxins, the plastics and manmade pollutants we are putting into the ocean.
"So they work their way up the food chain into the sharks. Typically they have large levels because they are a top predator."
Bermuda is increasingly alarmed by the amount of rubbish washing up on its shores.
It is on the edge of the Atlantic garbage patch, a swirling mass of plastic that is hundreds of kilometres wide and has been concentrated by the ocean currents.
Scientists trawling a fine-mesh net have found up to 200,000 pieces per square kilometre.
Most are just millimetres across - fragments of the myriad of plastic items in use today.
Sky News was taken by marine conservationist Chris Flook to Castle Island, a remote part of the Bermudan archipelago. High tide had brought in a sheen of almost invisible microplastic.
He said: "Out in the ocean you would see small fish and jellyfish feeding on stuff that is blue, white and purple.
"And (the plastic) we see here is blue, white and purple.
"This is the nightmare here, when the plastic gets to this size."
Eight million tonnes of plastic are dumped in the world's oceans every year. That is the equivalent of one full rubbish lorry's worth every minute.
But the plastic does not disappear - it just disintegrates into ever smaller pieces over several decades.
By 2050, it is predicted that so much plastic will have accumulated in the world's oceans that it will weigh more than all the fish combined.