CBS NEWS. -- A popular ingredient in beauty products could be creating a new environmental threat.
The potentially dangerous contaminants are known as "microbeads," and are no bigger than a grain of salt.
The tiny plastics are common in face and body washes.
Scientist Marcus Eriksen says the beads soak up pesticides and chemicals after they are washed down the drain.
"By the time the plastic gets downstream towards the ocean, they become these toxic pills," he said. "Even a small microbead, as it tumbles down stream, is picking up all kinds of industrial chemicals."
Eriksen is the executive director of the environmental advocacy group, 5 Gyres, and says up to 300,000 microbeads can be found in one tube of face scrub.
Eriksen believes many water treatment plants cannot filter out the tiny plastics, allowing them to flow into the ocean or waterways,where they can be mistaken for food.
"Big fish eat little fish, eventually the fish is on your dinner plate," Eriksen said. "And you're eating that fish, along with all the toxins it consumed along the way."
The Environmental Protection Agency is looking into potential dangers after Eriksen and his team uncovered high concentrations of microbeads in the Great Lakes.
"The same size, the same color, the same texture, in the same composition as the microbeads that we found [in the Great Lakes], we collected from common facial scrubbers on store shelves," Eriksen said. "They were the same color--little blue and red perfect spheres."
Several major cosmetic companies, including Procter & Gamble, Unilever, Johnson & Johnson, and Colgate-Palmolive have already pledged to phase out the use of microbeads.
Johnson and Johnson's Senior Communications Director, Carol Goodrich, says the company will eliminate microbeads from half its products by the end of next year.
"We have stopped developing new products containing polyethylene microbeads and have been conducting environmental safety assessments of other alternatives," Goodrich said. "These assessments are part of our 'informed substitution' approach, which helps ensure that the alternatives we choose are safe and environmentally sound."
The New York State Assembly passed legislation on Monday to ban the sale and distribution of products containing the tiny plastics. Lawmakers in California are considering following suit.
Eriksen recently began searching for microbeads in the Los Angeles River and found what he believes are more of the tiny plastics.
"The shape is very distinctive--a perfectly round little sphere--that's why it's suspicious," Eriksen said. "Analysis must be done further to see the composition, to see if they are actually plastic or not."
But Los Angeles Sanitation's Operations Chief Traci Minamide says city crews took their own samples along the Los Angeles River and at the Tillman Water Reclamation plant--one of three wastewater treatment facilities that feeds into the river.
"We found nothing," Minamide said. "The water is very clear. The beads can't get through our filters...we need to do more research as to what actually is the path of those microbeads."
Minamide says the Tillman plant can sift out particles 20 times smaller than microbeads.
Eriksen, however, said the tiny plastics are still somehow getting through.
He says across the country, most filters are not fine enough to stop microbeads from polluting waterways.
"They are not going to go away any time soon," Eriksen said. "And it may end up in the food that you eat."
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