A new study showed that concentrations of microplastic in the marine environment, which were traced mostly from synthetic clothes, could be eaten by animals and enter the food chain.
The researchers took samples from 18 beaches around the world in order to identify how widespread the presence of microplastic was on shorelines and they found out that there was no sample that did not contain pieces of microplastic.
The team also worked with a local authority in New South Wales, Australia to prove that sewerage discharges were the source of the plastic discharges. "We found exactly the same proportion of plastics," Dr Browne revealed, which led the team to conclude that their suspicions had been correct.
Microplastics are small plastic particles in the environment smaller than 1 mm pertaining to their microscopic size range. Earlier research showed plastic smaller than 1mm were being eaten by animals and getting into the food chain.
Dr Browne, a member of the US-based research network National Center for Ecological Analysis and Synthesis, said microplastics have become a major concern because evidence showed that it was making its way into the food chain.
"Once the plastics had been eaten, it transferred from [the animals'] stomachs to their circulation system and actually accumulated in their cells," Dr. Brown said.
The team did a number of experiments to find out what fibers were contained in the water discharge from washing machines. Their findings showed that some polyester garments released more than 1,900 fibers per garment, per wash.
"It may not sound like an awful lot, but if that is from a single item from a single wash, it shows how things can build up. It suggests to us that a large proportion of the fibers we were finding in the environment, in the strongest evidence yet, were derived from the sewerage as a consequence from washing clothes," Dr. Brown said.
In 2008, scientists gathered for the first International Research Workshop on the Occurrence, Effects and Fate of Microplastic Marine Debris and agreed that microplastics may pose problems in the marine environment.
Research has mainly focused on larger plastic items and the more common problems are associated with entanglement, ingestion, suffocation and general debilitation often leading to death and/or strandings which raises serious public concern.
The effects of microplastics, on the other hand, are not widely known but researchers have found out that these could be as damaging to marine life. Microplastics are less than 5 mm, but particles of this size are available to a much broader range of species and have been shown to be ingested by various species like deposit-feeding lugworms and filter-feeding mussels, according to researchers.
There are several suspected sources of microplastics, and these include those which are produced either for direct use, such as for industrial abrasives, exfoliants or cosmetics; those formed in the environment as a consequence of the breakdown of larger plastic material, and the shedding of synthetic fibers from textiles by domestic clothes washing.
Possible effects of microplastics on marine organisms after ingestion include physical blockage or damage of feeding appendages or digestive tract; leaching of plastic component chemicals into organisms after digestion, and ingestion and accumulation of absorbed chemicals by the organism.
Plastic debris has also been shown to serve as carrier for the dispersal of biota, which greatly increased dispersal opportunities in the oceans thus endangering marine biodiversity worldwide.
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