January 30, 2012
Researchers Analyze Source, Risk Of ‘Microplastic’ Pollution
Minute pieces of plastic debris smaller than a millimeter in size are accumulating in marine habitats, potentially contaminating the environment and entering the food chain, an international team of researchers has claimed.
Those tiny particles, identified by the researchers as "microplastic," originate from synthetic clothes and enters the water supply through washing machines, according to a Friday report by BBC News Environmental Reporter Mark Kinver. As many as 1,900 tiny fibers are released from each piece of clothing each time it is washed, he added.
Those pieces of microplastic are "accumulating in marine habitats," the Irish, Australian, Canadian, and UK team wrote in their study, which had been published in the journal Environmental Science and Technology.
"Ingestion of microplastic provides a potential pathway for the transfer of pollutants, monomers, and plastic-additives to organisms with uncertain consequences for their health," they added, noting that they studied contamination from these substances at 18 sites across six different continents.
There was "more material in densely populated areas," they said, but otherwise no defined correlation between the amount of microplastics and the distribution of natural particles. However, they discovered that one noteworthy source of the contamination was sewage containing fibers from washed clothes.
Specifically, they said that "the proportions of polyester and acrylic fibers used in clothing resembled those found in habitats that receive sewage-discharges and sewage-effluent itself," leading them to conclude that as the global population expands and becoming increasingly reliant on synthetic textiles, the contamination of these areas -- and the potential that animals will ingest these particles -- will most likely increase.
Co-author Mark Browne, who was affiliated with University College Dublin during the study but now works as an ecologist at the University of California, Santa Barbara, told Kinver that research he and his previous colleagues had completed previously showed that as much as 80% of all the plastic polluting the environment are microplastic particles. That discovery, he said, made they want to discover the source.
"Most of the plastic seemed to be fibrous," Browne said. "When we looked at the different types of polymers we were finding, we were finding that polyester, acrylic and polyamides (nylon) were the major ones that we were finding."
Areas near large, urban cities were found to have the highest concentration of the microplastic, he added.
One of the main reasons for concern is that the particles could be eaten by animals, and once that happened, the microplastic could be transferred from their stomachs to their circulation systems. In fact, they found that it could actually accumulate within their cells, Browne told the BBC.
Joining him on the research team were experts from the University of Sydney Centre for Research on the Ecological Impacts of Coastal Cities; both the Marine Biology & Ecology Research Group and the School of Geography at the University of Plymouth; Waters Canada; and the University of Exeter's School of Biosciences.
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